1
|
Jiang K, Wang J, Gao Y, Li X, Im H, Zhu Y, Du H, Feng L, Zhu W, Zhao G, Hu Y, Zhu P, Zhu W, Wang H, Wang Q. Microstructural and functional substrates underlying dispositional greed and its link with trait but not state impulsivity. Neuroimage 2024; 300:120856. [PMID: 39299662 DOI: 10.1016/j.neuroimage.2024.120856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2024] [Revised: 08/26/2024] [Accepted: 09/17/2024] [Indexed: 09/22/2024] Open
Abstract
The interplay between personality traits and impulsivity has long been a central theme in psychology and psychiatry. However, the potential association between Greed Personality Traits (GPT) and impulsivity, encompassing both trait and state impulsivity and future time perspective, remains largely unexplored. To address these issues, we employed questionnaires and an inter-temporal choice task to estimate corresponding trait/state impulsivity and collected multi-modal neuroimaging data (resting-state functional imaging: n = 430; diffusion-weighted imaging: n = 426; task-related functional imaging: n = 53) to investigate the underlying microstructural and functional substrates. Behavioral analyses revealed that GPT mediated the association between time perspective (e.g., present fatalism) and trait impulsivity (e.g., motor impulsivity). Functional imaging analyses further identified that brain activation strengths and patterns related to delay length, particularly in the dorsomedial prefrontal cortex, superior parietal lobule, and cerebellum, were associated with GPT. Moreover, individuals with similar levels of greed exhibited analogous spontaneous brain activity patterns, predominantly in the Default Mode Network (DMN), Fronto-Parietal Network (FPN), and Visual Network (VIS). Diffusion imaging analysis observed specific microstructural characteristics in the spinocerebellar/pontocerebellar fasciculus, internal/external capsule, and corona radiata that support the formation of GPT. Furthermore, the corresponding neural activation pattern, spontaneous neural activity pattern, and analogous functional couplings among the aforementioned brain regions mediated the relationships between time perspective and GPT and between GPT and motor impulsivity. These findings provide novel insights into the possible pathway such as time perspective → dispositional greed → impulsivity and uncover their underlying microstructural and functional substrates.
Collapse
Affiliation(s)
- Keying Jiang
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Jinlian Wang
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Yuanyuan Gao
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Xiang Li
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | | | - Yingying Zhu
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Hanxiao Du
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Lei Feng
- School of Mathematical Sciences, Tianjin Normal University, Tianjin 300387, PR China
| | - Wenwei Zhu
- School of Psychology, South China Normal University, Guangzhou 510631, PR China
| | - Guang Zhao
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Ying Hu
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - Peng Zhu
- Huzhou Key Laboratory of Brain Science and Child Learning, Huzhou University, Huzhou 300387, PR China
| | - Wenfeng Zhu
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China
| | - He Wang
- Tianjin Key Laboratory of Neuromodulation and Neurorepair, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, PR China.
| | - Qiang Wang
- Faculty of Psychology, Tianjin Normal University, Tianjin 300387, PR China; Huzhou Key Laboratory of Brain Science and Child Learning, Huzhou University, Huzhou 300387, PR China; Institute of Mathematics and Interdisciplinary Sciences, Tianjin Normal University, Tianjin 300387, PR China.
| |
Collapse
|
2
|
Santos CL, Weber FB, Belló-Klein A, Bobermin LD, Quincozes-Santos A. Glioprotective Effects of Sulforaphane in Hypothalamus: Focus on Aging Brain. Neurochem Res 2024; 49:2505-2518. [PMID: 38886329 DOI: 10.1007/s11064-024-04196-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 06/04/2024] [Accepted: 06/10/2024] [Indexed: 06/20/2024]
Abstract
Sulforaphane is a natural compound with neuroprotective activity, but its effects on hypothalamus remain unknown. In line with this, astrocytes are critical cells to maintain brain homeostasis, and hypothalamic astrocytes are fundamental for sensing and responding to environmental changes involved in a variety of homeostatic functions. Changes in brain functionality, particularly associated with hypothalamic astrocytes, can contribute to age-related neurochemical alterations and, consequently, neurodegenerative diseases. Thus, here, we investigated the glioprotective effects of sulforaphane on hypothalamic astrocyte cultures and hypothalamic cell suspension obtained from aged Wistar rats (24 months old). Sulforaphane showed anti-inflammatory and antioxidant properties, as well as modulated the mRNA expression of astroglial markers, such as aldehyde dehydrogenase 1 family member L1, aquaporin 4, and vascular endothelial growth factor. In addition, it increased the expression and extracellular levels of trophic factors, such as glia-derived neurotrophic factor and nerve growth factor, as well as the release of brain-derived neurotrophic factor and the mRNA of TrkA, which is a receptor associated with trophic factors. Sulforaphane also modulated the expression of classical pathways associated with glioprotection, including nuclear factor erythroid-derived 2-like 2, heme oxygenase-1, nuclear factor kappa B p65 subunit, and AMP-activated protein kinase. Finally, a cell suspension with neurons and glial cells was used to confirm the predominant effect of sulforaphane in glial cells. In summary, this study indicated the anti-aging and glioprotective activities of sulforaphane in aged astrocytes.
Collapse
Affiliation(s)
- Camila Leite Santos
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Fernanda Becker Weber
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Adriane Belló-Klein
- Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Larissa Daniele Bobermin
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - André Quincozes-Santos
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Laboratório de Neurotoxicidade e Glioproteção (LABGLIO), Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600 - Anexo, Bairro Santa Cecília, Porto Alegre, RS, 90035-003, Brazil.
| |
Collapse
|
3
|
Zou J, Li J, Wang X, Tang D, Chen R. Neuroimmune modulation in liver pathophysiology. J Neuroinflammation 2024; 21:188. [PMID: 39090741 PMCID: PMC11295927 DOI: 10.1186/s12974-024-03181-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 07/19/2024] [Indexed: 08/04/2024] Open
Abstract
The liver, the largest organ in the human body, plays a multifaceted role in digestion, coagulation, synthesis, metabolism, detoxification, and immune defense. Changes in liver function often coincide with disruptions in both the central and peripheral nervous systems. The intricate interplay between the nervous and immune systems is vital for maintaining tissue balance and combating diseases. Signaling molecules and pathways, including cytokines, inflammatory mediators, neuropeptides, neurotransmitters, chemoreceptors, and neural pathways, facilitate this complex communication. They establish feedback loops among diverse immune cell populations and the central, peripheral, sympathetic, parasympathetic, and enteric nervous systems within the liver. In this concise review, we provide an overview of the structural and compositional aspects of the hepatic neural and immune systems. We further explore the molecular mechanisms and pathways that govern neuroimmune communication, highlighting their significance in liver pathology. Finally, we summarize the current clinical implications of therapeutic approaches targeting neuroimmune interactions and present prospects for future research in this area.
Collapse
Affiliation(s)
- Ju Zou
- Hunan Key Laboratory of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
- Department of Infectious Diseases, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Jie Li
- Hunan Key Laboratory of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
- Department of Infectious Diseases, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Xiaoxu Wang
- Hunan Key Laboratory of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
- Department of Infectious Diseases, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Daolin Tang
- Department of Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Ruochan Chen
- Hunan Key Laboratory of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
- Department of Infectious Diseases, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
| |
Collapse
|
4
|
Hu K, Xu Y, Fan J, Liu H, Di C, Xu F, Wu L, Ding K, Zhang T, Wang L, Ai H, Xie L, Wang G, Liang Y. Feasibility exploration of GSH in the treatment of acute hepatic encephalopathy from the aspects of pharmacokinetics, pharmacodynamics, and mechanism. Front Pharmacol 2024; 15:1387409. [PMID: 38887546 PMCID: PMC11181355 DOI: 10.3389/fphar.2024.1387409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 05/06/2024] [Indexed: 06/20/2024] Open
Abstract
Our previous study highlighted the therapeutic potential of glutathione (GSH), an intracellular thiol tripeptide ubiquitous in mammalian tissues, in mitigating hepatic and cerebral damage. Building on this premise, we posited the hypothesis that GSH could be a promising candidate for treating acute hepatic encephalopathy (AHE). To verify this conjecture, we systematically investigated the feasibility of GSH as a therapeutic agent for AHE through comprehensive pharmacokinetic, pharmacodynamic, and mechanistic studies using a thioacetamide-induced AHE rat model. Our pharmacodynamic data demonstrated that oral GSH could significantly improve behavioral scores and reduce hepatic damage of AHE rats by regulating intrahepatic ALT, AST, inflammatory factors, and homeostasis of amino acids. Additionally, oral GSH demonstrated neuroprotective effects by alleviating the accumulation of intracerebral glutamine, down-regulating glutamine synthetase, and reducing taurine exposure. Pharmacokinetic studies suggested that AHE modeling led to significant decrease in hepatic and cerebral exposure of GSH and cysteine. However, oral GSH greatly enhanced the intrahepatic and intracortical GSH and CYS in AHE rats. Given the pivotal roles of CYS and GSH in maintaining redox homeostasis, we investigated the interplay between oxidative stress and pathogenesis/treatment of AHE. Our data revealed that GSH administration significantly relieved oxidative stress levels caused by AHE modeling via down-regulating the expression of NADPH oxidase 4 (NOX4) and NF-κB P65. Importantly, our findings further suggested that GSH administration significantly regulated the excessive endoplasmic reticulum (ER) stress caused by AHE modeling through the iNOS/ATF4/Ddit3 pathway. In summary, our study uncovered that exogenous GSH could stabilize intracerebral GSH and CYS levels to act on brain oxidative and ER stress, which have great significance for revealing the therapeutic effect of GSH on AHE and promoting its further development and clinical application.
Collapse
Affiliation(s)
- Kangrui Hu
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Yexin Xu
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Jiye Fan
- Department of Pharmacy, Hebei Chemical and Pharmaceutical College, Shijiazhuang, Hebei Province, China
| | - Huafang Liu
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Chanjuan Di
- Hebei Zhitong Biopharmaceutical Co., Ltd., Gucheng, Hebei Province, China
| | - Feng Xu
- Hebei Zhitong Biopharmaceutical Co., Ltd., Gucheng, Hebei Province, China
| | - Linlin Wu
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Ke Ding
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Tingting Zhang
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Leyi Wang
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Haoyu Ai
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Lin Xie
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | | | - Yan Liang
- Key Lab of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| |
Collapse
|
5
|
Cao Y, Xu W, Liu Q. Alterations of the blood-brain barrier during aging. J Cereb Blood Flow Metab 2024; 44:881-895. [PMID: 38513138 PMCID: PMC11318406 DOI: 10.1177/0271678x241240843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 02/19/2024] [Accepted: 02/28/2024] [Indexed: 03/23/2024]
Abstract
The blood-brain barrier (BBB) is a complex and dynamic interface that regulates the exchange of molecules and cells between the blood and the central nervous system. It undergoes structural and functional changes during aging, which may compromise its integrity and contribute to the pathogenesis of neurodegenerative diseases. In recent years, advances in microscopy and high-throughput bioinformatics have allowed a more in-depth investigation of the aging mechanisms of BBB. This review summarizes age-related alterations of the BBB structure and function from six perspectives: endothelial cells, astrocytes, pericytes, basement membrane, microglia and perivascular macrophages, and fibroblasts, ranging from the molecular level to the human multi-system level. These basic components are essential for the proper functioning of the BBB. Recent imaging methods of BBB were also reviewed. Elucidation of age-associated BBB changes may offer insights into BBB homeostasis and may provide effective therapeutic strategies to protect it during aging.
Collapse
Affiliation(s)
- Yufan Cao
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Weihai Xu
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Qing Liu
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| |
Collapse
|
6
|
Zhao L, Zhang Z, Wang P, Zhang N, Shen H, Wu H, Wei Z, Yang F, Wang Y, Yu Z, Li H, Hu Z, Zhai H, Wang Z, Su F, Xie K, Li Y. NHH promotes Sepsis-associated Encephalopathy with the expression of AQP4 in astrocytes through the gut-brain Axis. J Neuroinflammation 2024; 21:138. [PMID: 38802927 PMCID: PMC11131257 DOI: 10.1186/s12974-024-03135-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 05/20/2024] [Indexed: 05/29/2024] Open
Abstract
Sepsis-associated encephalopathy (SAE) is a significant cause of mortality in patients with sepsis. Despite extensive research, its exact cause remains unclear. Our previous research indicated a relationship between non-hepatic hyperammonemia (NHH) and SAE. This study aimed to investigate the relationship between NHH and SAE and the potential mechanisms causing cognitive impairment. In the in vivo experimental results, there were no significant abnormalities in the livers of mice with moderate cecal ligation and perforation (CLP); however, ammonia levels were elevated in the hippocampal tissue and serum. The ELISA study suggest that fecal microbiota transplantation in CLP mice can reduce ammonia levels. Reduction in ammonia levels improved cognitive dysfunction and neurological impairment in CLP mice through behavioral, neuroimaging, and molecular biology studies. Further studies have shown that ammonia enters the brain to regulate the expression of aquaporins-4 (AQP4) in astrocytes, which may be the mechanism underlying brain dysfunction in CLP mice. The results of the in vitro experiments showed that ammonia up-regulated AQP4 expression in astrocytes, resulting in astrocyte damage. The results of this study suggest that ammonia up-regulates astrocyte AQP4 expression through the gut-brain axis, which may be a potential mechanism for the occurrence of SAE.
Collapse
Affiliation(s)
- Lina Zhao
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Zhen Zhang
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Pei Wang
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Nannan Zhang
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Hao Shen
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Hening Wu
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Zhiyong Wei
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Fei Yang
- Department of Critical Care Medicine, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, 024000, China
| | - Yunying Wang
- Department of Critical Care Medicine, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, 024000, China
| | - Zhijie Yu
- Department of Critical Care Medicine, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, 024000, China
| | - Haibo Li
- Department of Anesthesiology, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, 024000, China
| | - Zhanfei Hu
- Department of Anesthesiology, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, 024000, China
| | - Hongyan Zhai
- Department of Ultrasound, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Zhiwei Wang
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Fuhong Su
- Experimental Laboratory of the Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, 1070, Belgium
| | - Keliang Xie
- Department of Critical Care Medicine, Tianjin Medical University General Hospital, Tianjin, 300052, China.
- Department of Anesthesiology, Tianjin Institute of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China.
| | - Yun Li
- Department of Anesthesiology, Tianjin Institute of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China.
| |
Collapse
|
7
|
Wang Y, Cheng C, Lu Y, Lian Z, Liu Q, Xu Y, Li Y, Li H, Zhang L, Jiang X, Li B, Yu D. β-Catenin Activation Reprograms Ammonia Metabolism to Promote Senescence Resistance in Hepatocellular Carcinoma. Cancer Res 2024; 84:1643-1658. [PMID: 38417136 DOI: 10.1158/0008-5472.can-23-0673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 11/26/2023] [Accepted: 02/20/2024] [Indexed: 03/01/2024]
Abstract
Hepatocellular carcinoma (HCC) is a typical tumor that undergoes metabolic reprogramming, differing from normal liver tissue in glucose, lipid, nucleic acid, and amino acid metabolism. Although ammonia is a toxic metabolic by-product, it has also been recently recognized as a signaling molecule to activate lipid metabolism, and it can be a nitrogen source for biosynthesis to support tumorigenesis. In this study, we revealed that β-catenin activation increases ammonia production in HCC mainly by stimulating glutaminolysis. β-Catenin/LEF1 activated the transcription of the glutamate dehydrogenase GLUD1, which then promoted ammonia utilization to enhance the production of glutamate, aspartate, and proline as evidenced by 15NH4Cl metabolic flux. β-Catenin/TCF4 induced the transcription of SLC4A11, an ammonia transporter, to excrete excess ammonia. SLC4A11 was upregulated in HCC tumor tissues, and high SLC4A11 expression was associated with poor prognosis and advanced disease stages. Loss of SLC4A11 induced HCC cell senescence in vitro by blocking ammonia excretion and reduced β-catenin-driven tumor growth in vivo. Furthermore, elevated levels of plasma ammonia promoted the progression of β-catenin mutant HCC, which was impeded by SLC4A11 deficiency. Downregulation of SLC4A11 led to ammonia accumulation in tumor interstitial fluid and decreased plasma ammonia levels in HCC with activated β-catenin. Altogether, this study indicates that β-catenin activation reprograms ammonia metabolism and that blocking ammonia excretion by targeting SLC4A11 could be a promising approach to induce senescence in β-catenin mutant HCC. SIGNIFICANCE Ammonia metabolism reprogramming mediated by aberrant activation of β-catenin induces resistance to senescence in HCC and can be targeted by inhibiting SLC4A11 as a potential therapy for β-catenin mutant liver cancer.
Collapse
Affiliation(s)
- Ye Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Chunxiao Cheng
- Department of Hepatobiliary, Nanjing Drum Tower Hospital Clinical College of Nanjing University of Chinese Medicine, Nanjing, China
| | - Yanjun Lu
- Department of Hepatobiliary, Nanjing Drum Tower Hospital Clinical College of Nanjing University of Chinese Medicine, Nanjing, China
| | - Zhaowu Lian
- Department of Hepatobiliary, Nanjing Drum Tower Hospital Clinical College of Nanjing University of Chinese Medicine, Nanjing, China
| | - Qi Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Yanchao Xu
- Department of Hepatobiliary, Nanjing Drum Tower Hospital, the Affiliated Hospital of Jiangsu University, Nanjing, China
| | - Yunzheng Li
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Huan Li
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Laizhu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Xiang Jiang
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Binghua Li
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Decai Yu
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Hepatobiliary and Transplantation Surgery, Department of General Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Hepatobiliary, Nanjing Drum Tower Hospital Clinical College of Nanjing University of Chinese Medicine, Nanjing, China
- Department of Hepatobiliary, Nanjing Drum Tower Hospital, the Affiliated Hospital of Jiangsu University, Nanjing, China
| |
Collapse
|
8
|
Song Q, Hwang CL, Li Y, Wang J, Park J, Lee SM, Sun Z, Sun J, Xia Y, Nieto N, Cordoba-Chacon J, Jiang Y, Dou X, Song Z. Gut-derived ammonia contributes to alcohol-related fatty liver development via facilitating ethanol metabolism and provoking ATF4-dependent de novo lipogenesis activation. Metabolism 2024; 151:155740. [PMID: 37995805 DOI: 10.1016/j.metabol.2023.155740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/28/2023] [Accepted: 11/15/2023] [Indexed: 11/25/2023]
Abstract
BACKGROUND & AIMS Dysbiosis contributes to alcohol-associated liver disease (ALD); however, the precise mechanisms remain elusive. Given the critical role of the gut microbiota in ammonia production, we herein aim to investigate whether and how gut-derived ammonia contributes to ALD. METHODS Blood samples were collected from human subjects with/without alcohol drinking. Mice were exposed to the Lieber-DeCarli isocaloric control or ethanol-containing diets with and without rifaximin (a nonabsorbable antibiotic clinically used for lowering gut ammonia production) supplementation for five weeks. Both in vitro (NH4Cl exposure of AML12 hepatocytes) and in vivo (urease administration for 5 days in mice) hyperammonemia models were employed. RNA sequencing and fecal amplicon sequencing were performed. Ammonia and triglyceride concentrations were measured. The gene and protein expression of enzymes involved in multiple pathways were measured. RESULTS Chronic alcohol consumption causes hyperammonemia in both mice and human subjects. In healthy livers and hepatocytes, ammonia exposure upregulates the expression of urea cycle genes, elevates hepatic de novo lipogenesis (DNL), and increases fat accumulation. Intriguingly, ammonia promotes ethanol catabolism and acetyl-CoA formation, which, together with ammonia, synergistically facilitates intracellular fat accumulation in hepatocytes. Mechanistic investigations uncovered that ATF4 activation, as a result of ER stress induction and general control nonderepressible 2 activation, plays a central role in ammonia-provoked DNL elevation. Rifaximin ameliorates ALD pathologies in mice, concomitant with blunted hepatic ER stress induction, ATF4 activation, and DNL activation. CONCLUSIONS An overproduction of ammonia by gut microbiota, synergistically interacting with ethanol, is a significant contributor to ALD pathologies.
Collapse
Affiliation(s)
- Qing Song
- Department of Kinesiology and Nutrition, University of Illinois Chicago, Chicago, IL, USA.
| | - Chueh-Lung Hwang
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Yanhui Li
- Department of Kinesiology and Nutrition, University of Illinois Chicago, Chicago, IL, USA
| | - Jun Wang
- Department of Kinesiology and Nutrition, University of Illinois Chicago, Chicago, IL, USA
| | - Jooman Park
- Department of Physiology & Biophysics, University of Illinois Chicago, Chicago, IL, USA
| | - Samuel M Lee
- Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Illinois Chicago, Chicago, IL, USA
| | - Zhaoli Sun
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jun Sun
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Illinois Chicago, Chicago, IL, USA
| | - Yinglin Xia
- Department of Medicine, University of Illinois Chicago, Chicago, IL, USA
| | - Natalia Nieto
- Department of Pathology, University of Illinois Chicago, Chicago, IL, USA
| | - Jose Cordoba-Chacon
- Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Illinois Chicago, Chicago, IL, USA
| | - Yuwei Jiang
- Department of Physiology & Biophysics, University of Illinois Chicago, Chicago, IL, USA
| | - Xiaobing Dou
- College of Life Sciences, Zhejiang Chinese Medicine University, Hangzhou, Zhejiang, China
| | - Zhenyuan Song
- Department of Kinesiology and Nutrition, University of Illinois Chicago, Chicago, IL, USA.
| |
Collapse
|
9
|
Cheng Y, Zhang XD, Chen C, He LF, Li FF, Lu ZN, Man WQ, Zhao YJ, Chang ZX, Wu Y, Shen W, Fan LZ, Xu JH. Dynamic evolution of brain structural patterns in liver transplantation recipients: a longitudinal study based on 3D convolutional neuronal network model. Eur Radiol 2023; 33:6134-6144. [PMID: 37014408 DOI: 10.1007/s00330-023-09604-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 02/19/2023] [Accepted: 02/24/2023] [Indexed: 04/05/2023]
Abstract
OBJECTIVES To evaluate the dynamic evolution process of overall brain health in liver transplantation (LT) recipients, we employed a deep learning-based neuroanatomic biomarker to measure longitudinal changes of brain structural patterns before and 1, 3, and 6 months after surgery. METHODS Because of the ability to capture patterns across all voxels from a brain scan, the brain age prediction method was adopted. We constructed a 3D-CNN model through T1-weighted MRI of 3609 healthy individuals from 8 public datasets and further applied it to a local dataset of 60 LT recipients and 134 controls. The predicted age difference (PAD) was calculated to estimate brain changes before and after LT, and the network occlusion sensitivity analysis was used to determine the importance of each network in age prediction. RESULTS The PAD of patients with cirrhosis increased markedly at baseline (+ 5.74 years) and continued to increase within one month after LT (+ 9.18 years). After that, the brain age began to decrease gradually, but it was still higher than the chronological age. The PAD values of the OHE subgroup were higher than those of the no-OHE, and the discrepancy was more obvious at 1-month post-LT. High-level cognition-related networks were more important in predicting the brain age of patients with cirrhosis at baseline, while the importance of primary sensory networks increased temporarily within 6-month post-LT. CONCLUSIONS The brain structural patterns of LT recipients showed inverted U-shaped dynamic change in the early stage after transplantation, and the change in primary sensory networks may be the main contributor. KEY POINTS • The recipients' brain structural pattern showed an inverted U-shaped dynamic change after LT. • The patients' brain aging aggravated within 1 month after surgery, and the subset of patients with a history of OHE was particularly affected. • The change of primary sensory networks is the main contributor to the change in brain structural patterns.
Collapse
Affiliation(s)
- Yue Cheng
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
- College of Intelligence and Computing, Tianjin Key Laboratory of Cognitive Computing and Application, Tianjin University, Tianjin, China
| | - Xiao-Dong Zhang
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
- College of Intelligence and Computing, Tianjin Key Laboratory of Cognitive Computing and Application, Tianjin University, Tianjin, China
| | - Cheng Chen
- College of Intelligence and Computing, Tianjin Key Laboratory of Cognitive Computing and Application, Tianjin University, Tianjin, China
- Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Ling-Fei He
- College of Intelligence and Computing, Tianjin Key Laboratory of Cognitive Computing and Application, Tianjin University, Tianjin, China
- Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Fang-Fei Li
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Zi-Ning Lu
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Wei-Qi Man
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Yu-Jiao Zhao
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | | | - Ying Wu
- School of Statistics and Data Science, Key Laboratory for Medical Data Analysis and Statistical Research of Tianjin, Nankai University, Tianjin, China
| | - Wen Shen
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Ling-Zhong Fan
- Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Jun-Hai Xu
- College of Intelligence and Computing, Tianjin Key Laboratory of Cognitive Computing and Application, Tianjin University, Tianjin, China.
| |
Collapse
|
10
|
Mishra S, Welch N, Karthikeyan M, Bellar A, Musich R, Singh SS, Zhang D, Sekar J, Attaway A, Chelluboyina AK, Lorkowski SW, Roychowdhury S, Li L, Willard B, Smith JD, Hoppel C, Vachharajani V, Kumar A, Dasarathy S. Dysregulated cellular redox status during hyperammonemia causes mitochondrial dysfunction and senescence by inhibiting sirtuin-mediated deacetylation. Aging Cell 2023; 22:e13852. [PMID: 37101412 PMCID: PMC10352558 DOI: 10.1111/acel.13852] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 03/29/2023] [Accepted: 03/31/2023] [Indexed: 04/28/2023] Open
Abstract
Perturbed metabolism of ammonia, an endogenous cytotoxin, causes mitochondrial dysfunction, reduced NAD+ /NADH (redox) ratio, and postmitotic senescence. Sirtuins are NAD+ -dependent deacetylases that delay senescence. In multiomics analyses, NAD metabolism and sirtuin pathways are enriched during hyperammonemia. Consistently, NAD+ -dependent Sirtuin3 (Sirt3) expression and deacetylase activity were decreased, and protein acetylation was increased in human and murine skeletal muscle/myotubes. Global acetylomics and subcellular fractions from myotubes showed hyperammonemia-induced hyperacetylation of cellular signaling and mitochondrial proteins. We dissected the mechanisms and consequences of hyperammonemia-induced NAD metabolism by complementary genetic and chemical approaches. Hyperammonemia inhibited electron transport chain components, specifically complex I that oxidizes NADH to NAD+ , that resulted in lower redox ratio. Ammonia also caused mitochondrial oxidative dysfunction, lower mitochondrial NAD+ -sensor Sirt3, protein hyperacetylation, and postmitotic senescence. Mitochondrial-targeted Lactobacillus brevis NADH oxidase (MitoLbNOX), but not NAD+ precursor nicotinamide riboside, reversed ammonia-induced oxidative dysfunction, electron transport chain supercomplex disassembly, lower ATP and NAD+ content, protein hyperacetylation, Sirt3 dysfunction and postmitotic senescence in myotubes. Even though Sirt3 overexpression reversed ammonia-induced hyperacetylation, lower redox status or mitochondrial oxidative dysfunction were not reversed. These data show that acetylation is a consequence of, but is not the mechanism of, lower redox status or oxidative dysfunction during hyperammonemia. Targeting NADH oxidation is a potential approach to reverse and potentially prevent ammonia-induced postmitotic senescence in skeletal muscle. Since dysregulated ammonia metabolism occurs with aging, and NAD+ biosynthesis is reduced in sarcopenia, our studies provide a biochemical basis for cellular senescence and have relevance in multiple tissues.
Collapse
Affiliation(s)
- Saurabh Mishra
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Nicole Welch
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
- Departments of Gastroenterology and HepatologyCleveland ClinicClevelandOhioUSA
| | - Manikandan Karthikeyan
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Annette Bellar
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Ryan Musich
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Shashi Shekhar Singh
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Dongmei Zhang
- Proteomics and Metabolomics coreLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Jinendiran Sekar
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Amy H. Attaway
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
- Departments of Pulmonary MedicineCleveland ClinicClevelandOhioUSA
| | - Aruna Kumar Chelluboyina
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Shuhui Wang Lorkowski
- Cardiovascular and Metabolic SciencesLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Sanjoy Roychowdhury
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Ling Li
- Proteomics and Metabolomics coreLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Belinda Willard
- Proteomics and Metabolomics coreLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Jonathan D. Smith
- Cardiovascular and Metabolic SciencesLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Charles L. Hoppel
- Department of PharmacologyCase Western Reserve University School of MedicineClevelandOhioUSA
| | - Vidula Vachharajani
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
- Critical Care Medicine, Respiratory Institute, Cleveland ClinicClevelandOhioUSA
| | - Avinash Kumar
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
| | - Srinivasan Dasarathy
- Department of Inflammation and ImmunityLerner Research Institute, Cleveland ClinicClevelandOhioUSA
- Departments of Gastroenterology and HepatologyCleveland ClinicClevelandOhioUSA
| |
Collapse
|
11
|
Thomsen KL, Eriksen PL, Kerbert AJC, De Chiara F, Jalan R, Vilstrup H. Role of ammonia in NAFLD: An unusual suspect. JHEP Rep 2023; 5:100780. [PMID: 37425212 PMCID: PMC10326708 DOI: 10.1016/j.jhepr.2023.100780] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 07/11/2023] Open
Abstract
Mechanistically, the symptomatology and disease progression of non-alcoholic fatty liver disease (NAFLD) remain poorly understood, which makes therapeutic progress difficult. In this review, we focus on the potential importance of decreased urea cycle activity as a pathogenic mechanism. Urea synthesis is an exclusive hepatic function and is the body's only on-demand and definitive pathway to remove toxic ammonia. The compromised urea cycle activity in NAFLD is likely caused by epigenetic damage to urea cycle enzyme genes and increased hepatocyte senescence. When the urea cycle is dysfunctional, ammonia accumulates in liver tissue and blood, as has been demonstrated in both animal models and patients with NAFLD. The problem may be augmented by parallel changes in the glutamine/glutamate system. In the liver, the accumulation of ammonia leads to inflammation, stellate cell activation and fibrogenesis, which is partially reversible. This may be an important mechanism for the transition of bland steatosis to steatohepatitis and further to cirrhosis and hepatocellular carcinoma. Systemic hyperammonaemia has widespread negative effects on other organs. Best known are the cerebral consequences that manifest as cognitive disturbances, which are prevalent in patients with NAFLD. Furthermore, high ammonia levels induce a negative muscle protein balance leading to sarcopenia, compromised immune function and increased risk of liver cancer. There is currently no rational way to reverse reduced urea cycle activity but there are promising animal and human reports of ammonia-lowering strategies correcting several of the mentioned untoward aspects of NAFLD. In conclusion, the ability of ammonia-lowering strategies to control the symptoms and prevent the progression of NAFLD should be explored in clinical trials.
Collapse
Affiliation(s)
- Karen Louise Thomsen
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Denmark
- UCL Institute of Liver and Digestive Health, University College London, United Kingdom
| | - Peter Lykke Eriksen
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Denmark
| | - Annarein JC. Kerbert
- UCL Institute of Liver and Digestive Health, University College London, United Kingdom
| | - Francesco De Chiara
- UCL Institute of Liver and Digestive Health, University College London, United Kingdom
| | - Rajiv Jalan
- UCL Institute of Liver and Digestive Health, University College London, United Kingdom
- European Foundation for the Study of Chronic Liver Failure, Barcelona, Spain
| | - Hendrik Vilstrup
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Denmark
| |
Collapse
|
12
|
Claeys W, Van Hoecke L, Lernout H, De Nolf C, Van Imschoot G, Van Wonterghem E, Verhaege D, Castelein J, Geerts A, Van Steenkiste C, Vandenbroucke RE. Experimental hepatic encephalopathy causes early but sustained glial transcriptional changes. J Neuroinflammation 2023; 20:130. [PMID: 37248507 DOI: 10.1186/s12974-023-02814-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 05/21/2023] [Indexed: 05/31/2023] Open
Abstract
Hepatic encephalopathy (HE) is a common complication of liver cirrhosis, associated with high morbidity and mortality, for which no brain-targeted therapies exist at present. The interplay between hyperammonemia and inflammation is thought to drive HE development. As such, astrocytes, the most important ammonia-metabolizing cells in the brain, and microglia, the main immunomodulatory cells in the brain, have been heavily implicated in HE development. As insight into cellular perturbations driving brain pathology remains largely elusive, we aimed to investigate cell-type specific transcriptomic changes in the HE brain. In the recently established mouse bile duct ligation (BDL) model of HE, we performed RNA-Seq of sorted astrocytes and microglia at 14 and 28 days after induction. This revealed a marked transcriptional response in both cell types which was most pronounced in microglia. In both cell types, pathways related to inflammation and hypoxia, mechanisms commonly implicated in HE, were enriched. Additionally, astrocytes exhibited increased corticoid receptor and oxidative stress signaling, whereas microglial transcriptome changes were linked to immune cell attraction. Accordingly, both monocytes and neutrophils accumulated in the BDL mouse brain. Time-dependent changes were limited in both cell types, suggesting early establishment of a pathological phenotype. While HE is often considered a unique form of encephalopathy, astrocytic and microglial transcriptomes showed significant overlap with previously established gene expression signatures in other neuroinflammatory diseases like septic encephalopathy and stroke, suggesting common pathophysiological mechanisms. Our dataset identifies key molecular mechanisms involved in preclinical HE and provides a valuable resource for development of novel glial-directed therapeutic strategies.
Collapse
Affiliation(s)
- Wouter Claeys
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Ghent University, 9000, Ghent, Belgium
- Liver Research Center Ghent, Ghent University Hospital, Ghent University, 9000, Ghent, Belgium
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
| | - Lien Van Hoecke
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
| | - Hannah Lernout
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- IBD Research Unit, Department of Internal Medicine and Paediatrics, Ghent University, 9000, Ghent, Belgium
| | - Clint De Nolf
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
- Department of Internal Medicine and Paediatrics, Ghent University, 9000, Ghent, Belgium
| | - Griet Van Imschoot
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
| | - Elien Van Wonterghem
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
| | - Daan Verhaege
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
| | - Jonas Castelein
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium
| | - Anja Geerts
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Ghent University, 9000, Ghent, Belgium
- Liver Research Center Ghent, Ghent University Hospital, Ghent University, 9000, Ghent, Belgium
- Department of Gastroenterology and Hepatology, Ghent University Hospital, Ghent, Belgium
| | - Christophe Van Steenkiste
- Department of Gastroenterology and Hepatology, Antwerp University, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Maria Middelares Hospital, Ghent, Belgium
| | - Roosmarijn E Vandenbroucke
- Barriers in Inflammation, VIB Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium.
- Department of Biomedical Molecular Biology, Ghent University, 9000, Ghent, Belgium.
| |
Collapse
|
13
|
Hu SH, Feng YY, Yang YX, Ma HD, Zhou SX, Qiao YN, Zhang KH, Zhang L, Huang L, Yuan YY, Lin Y, Zhang XY, Li Y, Li HT, Zhao JY, Xu W, Zhao SM. Amino acids downregulate SIRT4 to detoxify ammonia through the urea cycle. Nat Metab 2023; 5:626-641. [PMID: 37081161 DOI: 10.1038/s42255-023-00784-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 03/10/2023] [Indexed: 04/22/2023]
Abstract
Ammonia production via glutamate dehydrogenase is inhibited by SIRT4, a sirtuin that displays both amidase and non-amidase activities. The processes underlying the regulation of ammonia removal by amino acids remain unclear. Here, we report that SIRT4 acts as a decarbamylase that responds to amino acid sufficiency and regulates ammonia removal. Amino acids promote lysine 307 carbamylation (OTCCP-K307) of ornithine transcarbamylase (OTC), which activates OTC and the urea cycle. Proteomic and interactome screening identified OTC as a substrate of SIRT4. SIRT4 decarbamylates OTCCP-K307 and inactivates OTC in an NAD+-dependent manner. SIRT4 expression was transcriptionally upregulated by the amino acid insufficiency-activated GCN2-eIF2α-ATF4 axis. SIRT4 knockout in cultured cells caused higher OTCCP-K307 levels, activated OTC, elevated urea cycle intermediates and urea production via amino acid catabolism. Sirt4 ablation decreased male mouse blood ammonia levels and ameliorated CCl4-induced hepatic encephalopathy phenotypes. We reveal that SIRT4 safeguards cellular ammonia toxicity during amino acid catabolism.
Collapse
Affiliation(s)
- Song-Hua Hu
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Yu-Yang Feng
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
- Key Laboratory for Tibet Plateau Phytochemistry of Qinghai Province, College of Pharmacy, Qinghai University for Nationalities, Xining, China
| | - Yuan-Xin Yang
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Hui-Da Ma
- MOE Key Laboratory of Protein Sciences, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Centre for Life Sciences, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing, China
| | - Shu-Xian Zhou
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Ya-Nan Qiao
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Kai-Hui Zhang
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Lei Zhang
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Lin Huang
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Yi-Yuan Yuan
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Yan Lin
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
- Key Laboratory for Tibet Plateau Phytochemistry of Qinghai Province, College of Pharmacy, Qinghai University for Nationalities, Xining, China
| | - Xin-Yan Zhang
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
- Key Laboratory for Tibet Plateau Phytochemistry of Qinghai Province, College of Pharmacy, Qinghai University for Nationalities, Xining, China
| | - Yao Li
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China
| | - Hai-Tao Li
- MOE Key Laboratory of Protein Sciences, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Centre for Life Sciences, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing, China
| | - Jian-Yuan Zhao
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China.
| | - Wei Xu
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China.
- Key Laboratory for Tibet Plateau Phytochemistry of Qinghai Province, College of Pharmacy, Qinghai University for Nationalities, Xining, China.
| | - Shi-Min Zhao
- The Obstetrics & Gynecology Hospital of Fudan University, Shanghai Key Laboratory of Metabolic Remodelling and Health, State Key Laboratory of Genetic Engineering, and Institutes of Biomedical Sciences, and Children's Hospital of Fudan University, Fudan University, Shanghai, China.
- Key Laboratory for Tibet Plateau Phytochemistry of Qinghai Province, College of Pharmacy, Qinghai University for Nationalities, Xining, China.
| |
Collapse
|
14
|
Rachmian N, Krizhanovsky V. Senescent cells in the brain and where to find them. FEBS J 2023; 290:1256-1266. [PMID: 36221897 DOI: 10.1111/febs.16649] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 09/25/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022]
Abstract
Cellular senescence is a process in which cells change their characteristic phenotype in response to stress and enter a state of prolonged cell cycle arrest accompanied by a distinct secretory phenotype. Cellular senescence has both beneficial and detrimental outcomes. With age, senescent cells progressively accumulate in tissues and might be the bridge connecting ageing to many age-related pathologies. In recent years, evidence emerged supporting the accumulation of brain senescent cells during neurological disorders and ageing. Here, we will discuss the different brain cell populations that exhibit a senescent phenotype. Subsequently, we will explore several senolytic strategies which have been developed to eliminate senescent cells. Finally, we will examine their potential to directly eliminate these senescent brain cells.
Collapse
Affiliation(s)
- Noa Rachmian
- Department of Molecular Cell Biology, The Weizmann Institute of Science, Rehovot, Israel.,Department of Brain Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Valery Krizhanovsky
- Department of Molecular Cell Biology, The Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
15
|
Cellular Pathogenesis of Hepatic Encephalopathy: An Update. Biomolecules 2023; 13:biom13020396. [PMID: 36830765 PMCID: PMC9953810 DOI: 10.3390/biom13020396] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/01/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Hepatic encephalopathy (HE) is a neuropsychiatric syndrome derived from metabolic disorders due to various liver failures. Clinically, HE is characterized by hyperammonemia, EEG abnormalities, and different degrees of disturbance in sensory, motor, and cognitive functions. The molecular mechanism of HE has not been fully elucidated, although it is generally accepted that HE occurs under the influence of miscellaneous factors, especially the synergistic effect of toxin accumulation and severe metabolism disturbance. This review summarizes the recently discovered cellular mechanisms involved in the pathogenesis of HE. Among the existing hypotheses, ammonia poisoning and the subsequent oxidative/nitrosative stress remain the mainstream theories, and reducing blood ammonia is thus the main strategy for the treatment of HE. Other pathological mechanisms mainly include manganese toxicity, autophagy inhibition, mitochondrial damage, inflammation, and senescence, proposing new avenues for future therapeutic interventions.
Collapse
|
16
|
Sepehrinezhad A, Shahbazi A, Sahab Negah S, Stolze Larsen F. New Insight Into Mechanisms of Hepatic Encephalopathy: An Integrative Analysis Approach to Identify Molecular Markers and Therapeutic Targets. Bioinform Biol Insights 2023; 17:11779322231155068. [PMID: 36814683 PMCID: PMC9940182 DOI: 10.1177/11779322231155068] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/17/2023] [Indexed: 02/19/2023] Open
Abstract
Hepatic encephalopathy (HE) is a set of complex neurological complications that arise from advanced liver disease. The precise molecular and cellular mechanism of HE is not fully understood. Differentially expressed genes (DEGs) from microarray technologies are powerful approaches to obtain new insight into the pathophysiology of HE. We analyzed microarray data sets of cirrhotic patients with HE from Gene Expression Omnibus to identify DEGs in postmortem cerebral tissues. Consequently, we uploaded significant DEGs into the STRING to specify protein-protein interactions. Cytoscape was used to reconstruct the genetic network and identify hub genes. Target genes were uploaded to different databases to perform comprehensive enrichment analysis and repurpose new therapeutic options for HE. A total of 457 DEGs were identified in 2 data sets totally from 12 cirrhotic patients with HE compared with 12 healthy subjects. We found that 274 genes were upregulated and 183 genes were downregulated. Network analyses on significant DEGs indicated 12 hub genes associated with HE. Enrichment analysis identified fatty acid beta-oxidation, cerebral organic acidurias, and regulation of actin cytoskeleton as main involved pathways associated with upregulated genes; serotonin receptor 2 and ELK-SRF/GATA4 signaling, GPCRs, class A rhodopsin-like, and p38 MAPK signaling pathway were related to downregulated genes. Finally, we predicted 39 probable effective drugs/agents for HE. This study not only confirms main important involved mechanisms of HE but also reveals some yet unknown activated molecular and cellular pathways in human HE. In addition, new targets were identified that could be of value in the future study of HE.
Collapse
Affiliation(s)
- Ali Sepehrinezhad
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Shahbazi
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Sajad Sahab Negah
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Neuroscience, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Fin Stolze Larsen
- Department of Hepatology CA-3163, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| |
Collapse
|
17
|
Kim JE, Park H, Kang TC. Peroxiredoxin 6 Regulates Glutathione Peroxidase 1-Medited Glutamine Synthase Preservation in the Hippocampus of Chronic Epilepsy Rats. Antioxidants (Basel) 2023; 12:antiox12010156. [PMID: 36671018 PMCID: PMC9855017 DOI: 10.3390/antiox12010156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/03/2023] [Accepted: 01/05/2023] [Indexed: 01/11/2023] Open
Abstract
Clasmatodendrosis (an autophagic astroglial degeneration) plays an important role in the regulation of spontaneous seizure duration but not seizure frequency or behavioral seizure severity in chronic epilepsy rats. Recently, it has been reported that N-acetylcysteine (NAC), a precursor to glutathione (GSH), attenuates clasmatodendritic degeneration and shortens spontaneous seizure duration in chronic epilepsy rats, although the underlying mechanisms of its anti-convulsive effects are not fully understood. To elucidate this, the present study was designed to investigate whether NAC affects astroglial glutamine synthase (GS) expression mediated by GSH peroxidase 1 (GPx1) and/or peroxiredoxin 6 (Prdx6) in the epileptic hippocampus. As compared to control animals, GS and GPx1 expressions were upregulated in reactive CA1 astrocytes of chronic epilepsy rats, while their expressions were significantly decreased in clasmatodendritic CA1 astrocytes and reactive astrocytes within the molecular layer of the dentate gyrus. Prdx6 expression was increased in reactive CA1 astrocytes as well as clasmatodendritic CA1 astrocytes. In the molecular layer of the dentate gyrus, Prdx6 expression levels were similar to those in control animals. NAC ameliorated clasmatodendrosis through the increment of GS and GPx1 expressions, while it abolished Prdx6 upregulation. 1-hexadecyl-3-(trifluoroethgl)-sn-glycerol-2 phosphomethanol (MJ33, a selective inhibitor of aiPLA2 activity of Prdx6) alleviated clasmatodendrosis by enhancing GPx1 and GS expressions in clasmatodendritic CA1 astrocytes without changing the Prdx6 level. NAC or MJ33 did not affect GS, GPx1 and Prdx6 expression in astrocytes within the molecular layer of the dentate gyrus. These findings indicate that upregulated aiPLA2 activity of Prdx6 may abolish GPx1-mediated GS preservation and lead to clasmatodendrosis in CA1 astrocytes, which would extend spontaneous seizure duration due to impaired glutamate-glutamine conversion regulated by GS. Therefore, the present data suggest that aiPLA2 activity of Prdx6 in astrocytes may be one of the upstream effectors of seizure duration in the epileptic hippocampus.
Collapse
Affiliation(s)
- Ji-Eun Kim
- Department of Anatomy and Neurobiolog, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, Hallym University, Chuncheon 24252, Republic of Korea
| | - Hana Park
- Department of Anatomy and Neurobiolog, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, Hallym University, Chuncheon 24252, Republic of Korea
| | - Tae-Cheon Kang
- Department of Anatomy and Neurobiolog, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, Hallym University, Chuncheon 24252, Republic of Korea
- Correspondence: ; Tel.: +82-33-248-2524; Fax: +82-33-248-2525
| |
Collapse
|
18
|
Welch N, Singh SS, Musich R, Mansuri MS, Bellar A, Mishra S, Chelluboyina AK, Sekar J, Attaway AH, Li L, Willard B, Hornberger TA, Dasarathy S. Shared and unique phosphoproteomics responses in skeletal muscle from exercise models and in hyperammonemic myotubes. iScience 2022; 25:105325. [PMID: 36345342 PMCID: PMC9636548 DOI: 10.1016/j.isci.2022.105325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 08/22/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
Abstract
Skeletal muscle generation of ammonia, an endogenous cytotoxin, is increased during exercise. Perturbations in ammonia metabolism consistently occur in chronic diseases, and may blunt beneficial skeletal muscle molecular responses and protein homeostasis with exercise. Phosphorylation of skeletal muscle proteins mediates cellular signaling responses to hyperammonemia and exercise. Comparative bioinformatics and machine learning-based analyses of published and experimentally derived phosphoproteomics data identified differentially expressed phosphoproteins that were unique and shared between hyperammonemic murine myotubes and skeletal muscle from exercise models. Enriched processes identified in both hyperammonemic myotubes and muscle from exercise models with selected experimental validation included protein kinase A (PKA), calcium signaling, mitogen-activated protein kinase (MAPK) signaling, and protein homeostasis. Our approach of feature extraction from comparative untargeted "omics" data allows for selection of preclinical models that recapitulate specific human exercise responses and potentially optimize functional capacity and skeletal muscle protein homeostasis with exercise in chronic diseases.
Collapse
Affiliation(s)
- Nicole Welch
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Shashi Shekhar Singh
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Ryan Musich
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
| | - M. Shahid Mansuri
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Annette Bellar
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Saurabh Mishra
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
| | | | - Jinendiran Sekar
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Amy H. Attaway
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Ling Li
- Proteomics Core, Cleveland Clinic, Cleveland, OH 44195, USA
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - Belinda Willard
- Proteomics Core, Cleveland Clinic, Cleveland, OH 44195, USA
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - Troy A. Hornberger
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - Srinivasan Dasarathy
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, OH 44195, USA
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, OH 44195, USA
| |
Collapse
|
19
|
A mouse model of hepatic encephalopathy: bile duct ligation induces brain ammonia overload, glial cell activation and neuroinflammation. Sci Rep 2022; 12:17558. [PMID: 36266427 PMCID: PMC9585018 DOI: 10.1038/s41598-022-22423-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 10/14/2022] [Indexed: 01/13/2023] Open
Abstract
Hepatic encephalopathy (HE) is a common complication of chronic liver disease, characterized by an altered mental state and hyperammonemia. Insight into the brain pathophysiology of HE is limited due to a paucity of well-characterized HE models beyond the rat bile duct ligation (BDL) model. Here, we assess the presence of HE characteristics in the mouse BDL model. We show that BDL in C57Bl/6j mice induces motor dysfunction, progressive liver fibrosis, liver function failure and hyperammonemia, all hallmarks of HE. Swiss mice however fail to replicate the same phenotype, underscoring the importance of careful strain selection. Next, in-depth characterisation of metabolic disturbances in the cerebrospinal fluid of BDL mice shows glutamine accumulation and transient decreases in taurine and choline, indicative of brain ammonia overload. Moreover, mouse BDL induces glial cell dysfunction, namely microglial morphological changes with neuroinflammation and astrocyte reactivity with blood-brain barrier (BBB) disruption. Finally, we identify putative novel mechanisms involved in central HE pathophysiology, like bile acid accumulation and tryptophan-kynurenine pathway alterations. Our study provides the first comprehensive evaluation of a mouse model of HE in chronic liver disease. Additionally, this study further underscores the importance of neuroinflammation in the central effects of chronic liver disease.
Collapse
|
20
|
Tsai CY, Wu JCC, Wu CJ, Chan SHH. Protective role of VEGF/VEGFR2 signaling against high fatality associated with hepatic encephalopathy via sustaining mitochondrial bioenergetics functions. J Biomed Sci 2022; 29:47. [PMID: 35786324 PMCID: PMC9251935 DOI: 10.1186/s12929-022-00831-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 06/27/2022] [Indexed: 11/30/2022] Open
Abstract
Background The lack of better understanding of the pathophysiology and cellular mechanisms associated with high mortality seen in hepatic encephalopathy (HE), a neurological complication arising from acute hepatic failure, remains a challenging medical issue. Clinical reports showed that the degree of baroreflex dysregulation is related to the severity of HE. Furthermore, mitochondrial dysfunction in the rostral ventrolateral medulla (RVLM), a key component of the baroreflex loop that maintains blood pressure and sympathetic vasomotor tone, is known to underpin impairment of baroreflex. Realizing that in addition to angiogenic and vasculogenic effects, by acting on its key receptor (VEGFR2), vascular endothelial growth factor (VEGF) elicits neuroprotection via maintenance of mitochondrial function, the guiding hypothesis of the present study is that the VEGF/VEGFR2 signaling plays a protective role against mitochondrial dysfunction in the RVLM to ameliorate baroreflex dysregulation that underpins the high fatality associated with HE. Methods Physiological, pharmacological and biochemical investigations were carried out in proof-of-concept experiments using an in vitro model of HE that involved incubation of cultured mouse hippocampal neurons with ammonium chloride. This was followed by corroboratory experiments employing a mouse model of HE, in which adult male C57BL/6 mice and VEGFR2 wild-type and heterozygous mice received an intraperitoneal injection of azoxymethane, a toxin used to induce acute hepatic failure. Results We demonstrated that VEGFR2 is present in cultured neurons, and observed that whereas recombinant VEGF protein maintained cell viability, gene-knockdown of vegfr2 enhanced the reduction of cell viability in our in vitro model of HE. In our in vivo model of HE, we found that VEGFR2 heterozygous mice exhibited shorter survival rate and time when compared to wild-type mice. In C57BL/6 mice, there was a progressive reduction in VEGFR2 mRNA and protein expression, mitochondrial membrane potential and ATP levels, alongside augmentation of apoptotic cell death in the RVLM, accompanied by a decrease in baroreflex-mediated sympathetic vasomotor tone and hypotension. Immunoneutralization of VEGF exacerbated all those biochemical and physiological events. Conclusions Our results suggest that, acting via VEGFR2, the endogenous VEGF plays a protective role against high fatality associated with HE by amelioration of the dysregulated baroreflex-mediated sympathetic vasomotor tone through sustaining mitochondrial bioenergetics functions and eliciting antiapoptotic action in the RVLM. Supplementary Information The online version contains supplementary material available at 10.1186/s12929-022-00831-0.
Collapse
Affiliation(s)
- Ching-Yi Tsai
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
| | - Jacqueline C C Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chiung-Ju Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Samuel H H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| |
Collapse
|
21
|
Häussinger D, Dhiman RK, Felipo V, Görg B, Jalan R, Kircheis G, Merli M, Montagnese S, Romero-Gomez M, Schnitzler A, Taylor-Robinson SD, Vilstrup H. Hepatic encephalopathy. Nat Rev Dis Primers 2022; 8:43. [PMID: 35739133 DOI: 10.1038/s41572-022-00366-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/12/2022] [Indexed: 01/18/2023]
Abstract
Hepatic encephalopathy (HE) is a prognostically relevant neuropsychiatric syndrome that occurs in the course of acute or chronic liver disease. Besides ascites and variceal bleeding, it is the most serious complication of decompensated liver cirrhosis. Ammonia and inflammation are major triggers for the appearance of HE, which in patients with liver cirrhosis involves pathophysiologically low-grade cerebral oedema with oxidative/nitrosative stress, inflammation and disturbances of oscillatory networks in the brain. Severity classification and diagnostic approaches regarding mild forms of HE are still a matter of debate. Current medical treatment predominantly involves lactulose and rifaximin following rigorous treatment of so-called known HE precipitating factors. New treatments based on an improved pathophysiological understanding are emerging.
Collapse
Affiliation(s)
- Dieter Häussinger
- Department of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
| | - Radha K Dhiman
- Department of Hepatology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, (Uttar Pradesh), India
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Principe Felipe, Valencia, Spain
| | - Boris Görg
- Department of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Rajiv Jalan
- Liver Failure Group ILDH, Division of Medicine, UCL Medical School, Royal Free Campus, London, UK.,European Foundation for the Study of Chronic Liver Failure, Barcelona, Spain
| | - Gerald Kircheis
- Department of Gastroenterology, Diabetology and Hepatology, University Hospital Brandenburg an der Havel, Brandenburg Medical School, Brandenburg an der Havel, Germany
| | - Manuela Merli
- Department of Translational and Precision Medicine, Universita' degli Studi di Roma - Sapienza, Roma, Italy
| | | | - Manuel Romero-Gomez
- UCM Digestive Diseases, Virgen del Rocío University Hospital, Institute of Biomedicine of Seville (HUVR/CSIC/US), University of Seville, Seville, Spain
| | - Alfons Schnitzler
- Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Simon D Taylor-Robinson
- Department of Surgery and Cancer, St. Mary's Hospital Campus, Imperial College London, London, UK
| | - Hendrik Vilstrup
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| |
Collapse
|
22
|
Arjunan A, Sah DK, Jung YD, Song J. Hepatic Encephalopathy and Melatonin. Antioxidants (Basel) 2022; 11:antiox11050837. [PMID: 35624703 PMCID: PMC9137547 DOI: 10.3390/antiox11050837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/06/2022] [Accepted: 04/24/2022] [Indexed: 11/25/2022] Open
Abstract
Hepatic encephalopathy (HE) is a severe metabolic syndrome linked with acute/chronic hepatic disorders. HE is also a pernicious neuropsychiatric complication associated with cognitive decline, coma, and death. Limited therapies are available to treat HE, which is formidable to oversee in the clinic. Thus, determining a novel therapeutic approach is essential. The pathogenesis of HE has not been well established. According to various scientific reports, neuropathological symptoms arise due to excessive accumulation of ammonia, which is transported to the brain via the blood–brain barrier (BBB), triggering oxidative stress and inflammation, and disturbing neuronal-glial functions. The treatment of HE involves eliminating hyperammonemia by enhancing the ammonia scavenging mechanism in systemic blood circulation. Melatonin is the sole endogenous hormone linked with HE. Melatonin as a neurohormone is a potent antioxidant that is primarily synthesized and released by the brain’s pineal gland. Several HE and liver cirrhosis clinical studies have demonstrated impaired synthesis, secretion of melatonin, and circadian patterns. Melatonin can cross the BBB and is involved in various neuroprotective actions on the HE brain. Hence, we aim to elucidate how HE impairs brain functions, and elucidate the precise molecular mechanism of melatonin that reverses the HE effects on the central nervous system.
Collapse
Affiliation(s)
- Archana Arjunan
- Department of Anatomy, Chonnam National University Medical School, Hwasun 58128, Korea;
| | - Dhiraj Kumar Sah
- Department of Biochemistry, Chonnam National University Medical School, Hwasun 58128, Korea;
| | - Young Do Jung
- Department of Biochemistry, Chonnam National University Medical School, Hwasun 58128, Korea;
- Correspondence: (Y.D.J.); (J.S.); Tel.: +82-61-379-2706 (J.S.)
| | - Juhyun Song
- Department of Anatomy, Chonnam National University Medical School, Hwasun 58128, Korea;
- BioMedical Sciences Graduate Program (BMSGP), Chonnam National University, 264 Seoyangro, Hwasun 58128, Korea
- Correspondence: (Y.D.J.); (J.S.); Tel.: +82-61-379-2706 (J.S.)
| |
Collapse
|
23
|
Schrimpf A, Knappe O, Qvartskhava N, Poschmann G, Stühler K, Bidmon HJ, Luedde T, Häussinger D, Görg B. Hyperammonemia-induced changes in the cerebral transcriptome and proteome. Anal Biochem 2022; 641:114548. [DOI: 10.1016/j.ab.2022.114548] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 10/10/2021] [Accepted: 01/06/2022] [Indexed: 02/07/2023]
|
24
|
Kumar A, Welch N, Mishra S, Bellar A, Silva RN, Li L, Singh SS, Sharkoff M, Kerr A, Chelluboyina AK, Sekar J, Attaway AH, Hoppel C, Willard B, Davuluri G, Dasarathy S. Metabolic reprogramming during hyperammonemia targets mitochondrial function and postmitotic senescence. JCI Insight 2021; 6:154089. [PMID: 34935641 PMCID: PMC8783680 DOI: 10.1172/jci.insight.154089] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/03/2021] [Indexed: 12/27/2022] Open
Abstract
Ammonia is a cytotoxic metabolite with pleiotropic molecular and metabolic effects, including senescence induction. During dysregulated ammonia metabolism, which occurs in chronic diseases, skeletal muscle becomes a major organ for nonhepatocyte ammonia uptake. Muscle ammonia disposal occurs in mitochondria via cataplerosis of critical intermediary metabolite α-ketoglutarate, a senescence-ameliorating molecule. Untargeted and mitochondrially targeted data were analyzed by multiomics approaches. These analyses were validated experimentally to dissect the specific mitochondrial oxidative defects and functional consequences, including senescence. Responses to ammonia lowering in myotubes and in hyperammonemic portacaval anastomosis rat muscle were studied. Whole-cell transcriptomics integrated with whole-cell, mitochondrial, and tissue proteomics showed distinct temporal clusters of responses with enrichment of oxidative dysfunction and senescence-related pathways/proteins during hyperammonemia and after ammonia withdrawal. Functional and metabolic studies showed defects in electron transport chain complexes I, III, and IV; loss of supercomplex assembly; decreased ATP synthesis; increased free radical generation with oxidative modification of proteins/lipids; and senescence-associated molecular phenotype–increased β-galactosidase activity and expression of p16INK, p21, and p53. These perturbations were partially reversed by ammonia lowering. Dysregulated ammonia metabolism caused reversible mitochondrial dysfunction by transcriptional and translational perturbations in multiple pathways with a distinct skeletal muscle senescence-associated molecular phenotype.
Collapse
Affiliation(s)
| | | | | | | | | | - Ling Li
- Proteomics & Metabolomics Core, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | | | | | | | | | | | | | - Charles Hoppel
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Belinda Willard
- Proteomics & Metabolomics Core, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Gangarao Davuluri
- Department of Integrated Physiology and Molecular Metabolism, Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
| | - Srinivasan Dasarathy
- Department of Inflammation & Immunity and.,Department of Gastroenterology, Hepatology & Nutrition, Cleveland Clinic, Cleveland, Ohio, USA
| |
Collapse
|
25
|
Cheng L, Wang X, Ma X, Xu H, Yang Y, Zhang D. Effect of dihydromyricetin on hepatic encephalopathy associated with acute hepatic failure in mice. PHARMACEUTICAL BIOLOGY 2021; 59:557-564. [PMID: 33982639 PMCID: PMC8128201 DOI: 10.1080/13880209.2021.1917625] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
CONTEXT Hepatic encephalopathy (HE) is a complex neuropsychiatric disease caused by liver failure. Dihydromyricetin (DMY) is a traditional medicine used to treat liver injury. OBJECTIVE To investigate the effects of dihydromyricetin (DMY) on hepatic encephalopathy associated with acute hepatic failure mice models established by thioacetamide (TAA) exposure. MATERIALS AND METHODS Female BALB/c mouse were randomly divided into control, DMY, TAA, and TAA + DMY groups (n = 8). The first two groups were intraperitoneally injected with saline or 5 mg/kg DMY, respectively. The last two groups were injected with 600 mg/kg TAA to establish HE models, and then the mice in the last group were treated with 5 mg/kg DMY. Neurological and cognition functions were evaluated 24 and 48 h after injection. Mice were sacrificed after which livers and brains were obtained for immunoblot and histopathological analysis, while blood was collected for the analysis of liver enzymes. RESULTS In the TAA + DMY group, ALT and AST decreased to 145.31 ± 12.88 U/L and 309.51 ± 25.92 U/L, respectively, whereas ammonia and TBIL decreased to 415.67 ± 41.91 μmol/L and 3.31 ± 0.35 μmol/L, respectively. Moreover, MDA decreased to 10.74 ± 3.97 nmol/g, while SOD and GST increased to 398.69 ± 231.30 U/g and 41.37 ± 21.84 U/g, respectively. The neurological score decreased to 2.87 ± 0.63, and the number of GFAP-positive cells decreased to 41.10 ± 1.66. Furthermore, the protein levels of TNF-α, IL-6, and GABAA in the cortex decreased. CONCLUSIONS We speculate that DMY can serve as a novel treatment for HE.
Collapse
Affiliation(s)
- Long Cheng
- Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou, People’s Republic of China
| | - Xiaoying Wang
- Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou, People’s Republic of China
| | - Xueni Ma
- Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou, People’s Republic of China
| | - Huimei Xu
- Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou, People’s Republic of China
| | - Yifan Yang
- Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou, People’s Republic of China
| | - Dekui Zhang
- Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou, People’s Republic of China
- CONTACT Dekui Zhang Department of Gastroenterology, Lanzhou University Second Hospital, Lanzhou730030, People’s Republic of China
| |
Collapse
|
26
|
Claeys W, Van Hoecke L, Lefere S, Geerts A, Verhelst X, Van Vlierberghe H, Degroote H, Devisscher L, Vandenbroucke RE, Van Steenkiste C. The neurogliovascular unit in hepatic encephalopathy. JHEP Rep 2021; 3:100352. [PMID: 34611619 PMCID: PMC8476774 DOI: 10.1016/j.jhepr.2021.100352] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/14/2021] [Accepted: 07/23/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatic encephalopathy (HE) is a neurological complication of hepatic dysfunction and portosystemic shunting. It is highly prevalent in patients with cirrhosis and is associated with poor outcomes. New insights into the role of peripheral origins in HE have led to the development of innovative treatment strategies like faecal microbiota transplantation. However, this broadening of view has not been applied fully to perturbations in the central nervous system. The old paradigm that HE is the clinical manifestation of ammonia-induced astrocyte dysfunction and its secondary neuronal consequences requires updating. In this review, we will use the holistic concept of the neurogliovascular unit to describe central nervous system disturbances in HE, an approach that has proven instrumental in other neurological disorders. We will describe HE as a global dysfunction of the neurogliovascular unit, where blood flow and nutrient supply to the brain, as well as the function of the blood-brain barrier, are impaired. This leads to an accumulation of neurotoxic substances, chief among them ammonia and inflammatory mediators, causing dysfunction of astrocytes and microglia. Finally, glymphatic dysfunction impairs the clearance of these neurotoxins, further aggravating their effect on the brain. Taking a broader view of central nervous system alterations in liver disease could serve as the basis for further research into the specific brain pathophysiology of HE, as well as the development of therapeutic strategies specifically aimed at counteracting the often irreversible central nervous system damage seen in these patients.
Collapse
Key Words
- ABC, ATP-binding cassette
- ACLF, acute-on-chronic liver failure
- AD, acute decompensation
- ALF, acute liver failure
- AOM, azoxymethane
- AQP4, aquaporin 4
- Acute Liver Failure
- Ammonia
- BBB, blood-brain barrier
- BCRP, breast cancer resistance protein
- BDL, bile duct ligation
- Blood-brain barrier
- Brain edema
- CCL, chemokine ligand
- CCR, C-C chemokine receptor
- CE, cerebral oedema
- CLD, chronic liver disease
- CLDN, claudin
- CNS, central nervous system
- CSF, cerebrospinal fluid
- Cirrhosis
- Energy metabolism
- GS, glutamine synthetase
- Glymphatic system
- HE, hepatic encephalopathy
- HO-1, heme oxygenase 1
- IL-, interleukin
- MMP-9, matrix metalloproteinase 9
- MRP, multidrug resistance associated protein
- NGVU
- NGVU, neurogliovascular unit
- NKCC1, Na-K-2Cl cotransporter 1
- Neuroinflammation
- OCLN, occludin
- ONS, oxidative and nitrosative stress
- Oxidative stress
- P-gp, P-glycoprotein
- PCA, portacaval anastomosis
- PSS, portosystemic shunt
- S1PR2, sphingosine-1-phosphate receptor 2
- SUR1, sulfonylurea receptor 1
- Systemic inflammation
- TAA, thioacetamide
- TGFβ, transforming growth factor beta
- TJ, tight junction
- TNF, tumour necrosis factor
- TNFR1, tumour necrosis factor receptor 1
- ZO, zonula occludens
- mPT, mitochondrial pore transition
Collapse
Affiliation(s)
- Wouter Claeys
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
- Barriers in Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Lien Van Hoecke
- Barriers in Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Sander Lefere
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
- Gut-Liver Immunopharmacology Unit, Department of Basic and Applied Medical Sciences; Liver Research Center Ghent; Ghent University, Ghent, Belgium
| | - Anja Geerts
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Xavier Verhelst
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Hans Van Vlierberghe
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Helena Degroote
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Lindsey Devisscher
- Gut-Liver Immunopharmacology Unit, Department of Basic and Applied Medical Sciences; Liver Research Center Ghent; Ghent University, Ghent, Belgium
| | - Roosmarijn E. Vandenbroucke
- Barriers in Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Christophe Van Steenkiste
- Antwerp University, Department of Gastroenterology and Hepatology, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Maria Middelares Hospital, Ghent, Belgium
| |
Collapse
|
27
|
Zimmermann M, Reichert AS. Rapid metabolic and bioenergetic adaptations of astrocytes under hyperammonemia - a novel perspective on hepatic encephalopathy. Biol Chem 2021; 402:1103-1113. [PMID: 34331848 DOI: 10.1515/hsz-2021-0172] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 07/18/2021] [Indexed: 12/17/2022]
Abstract
Hepatic encephalopathy (HE) is a well-studied, neurological syndrome caused by liver dysfunctions. Ammonia, the major toxin during HE pathogenesis, impairs many cellular processes within astrocytes. Yet, the molecular mechanisms causing HE are not fully understood. Here we will recapitulate possible underlying mechanisms with a clear focus on studies revealing a link between altered energy metabolism and HE in cellular models and in vivo. The role of the mitochondrial glutamate dehydrogenase and its role in metabolic rewiring of the TCA cycle will be discussed. We propose an updated model of ammonia-induced toxicity that may also be exploited for therapeutic strategies in the future.
Collapse
Affiliation(s)
- Marcel Zimmermann
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany
| |
Collapse
|
28
|
Häussinger D, Butz M, Schnitzler A, Görg B. Pathomechanisms in hepatic encephalopathy. Biol Chem 2021; 402:1087-1102. [PMID: 34049427 DOI: 10.1515/hsz-2021-0168] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/12/2021] [Indexed: 02/06/2023]
Abstract
Hepatic encephalopathy (HE) is a frequent neuropsychiatric complication in patients with acute or chronic liver failure. Symptoms of HE in particular include disturbances of sensory and motor functions and cognition. HE is triggered by heterogeneous factors such as ammonia being a main toxin, benzodiazepines, proinflammatory cytokines and hyponatremia. HE in patients with liver cirrhosis is triggered by a low-grade cerebral edema and cerebral oxidative/nitrosative stress which bring about a number of functionally relevant alterations including posttranslational protein modifications, oxidation of RNA, gene expression changes and senescence. These alterations are suggested to impair astrocyte/neuronal functions and communication. On the system level, a global slowing of oscillatory brain activity and networks can be observed paralleling behavioral perceptual and motor impairments. Moreover, these changes are related to increased cerebral ammonia, alterations in neurometabolite and neurotransmitter concentrations and cortical excitability in HE patients.
Collapse
Affiliation(s)
- Dieter Häussinger
- Clinic for Gastroenterology, Hepatology, and Infectious Diseases, Heinrich Heine University, Moorenstr. 5, D-40225 Düsseldorf, Germany
| | - Markus Butz
- Department of Neurology/Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University, Moorenstr. 5, D-40225 Düsseldorf, Germany
| | - Alfons Schnitzler
- Department of Neurology/Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University, Moorenstr. 5, D-40225 Düsseldorf, Germany
| | - Boris Görg
- Clinic for Gastroenterology, Hepatology, and Infectious Diseases, Heinrich Heine University, Moorenstr. 5, D-40225 Düsseldorf, Germany
| |
Collapse
|
29
|
Welch N, Singh SS, Kumar A, Dhruba SR, Mishra S, Sekar J, Bellar A, Attaway AH, Chelluboyina A, Willard BB, Li L, Huo Z, Karnik SS, Esser K, Longworth MS, Shah YM, Davuluri G, Pal R, Dasarathy S. Integrated multiomics analysis identifies molecular landscape perturbations during hyperammonemia in skeletal muscle and myotubes. J Biol Chem 2021; 297:101023. [PMID: 34343564 PMCID: PMC8424232 DOI: 10.1016/j.jbc.2021.101023] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/16/2021] [Accepted: 07/28/2021] [Indexed: 12/27/2022] Open
Abstract
Ammonia is a cytotoxic molecule generated during normal cellular functions. Dysregulated ammonia metabolism, which is evident in many chronic diseases such as liver cirrhosis, heart failure, and chronic obstructive pulmonary disease, initiates a hyperammonemic stress response in tissues including skeletal muscle and in myotubes. Perturbations in levels of specific regulatory molecules have been reported, but the global responses to hyperammonemia are unclear. In this study, we used a multiomics approach to vertically integrate unbiased data generated using an assay for transposase-accessible chromatin with high-throughput sequencing, RNA-Seq, and proteomics. We then horizontally integrated these data across different models of hyperammonemia, including myotubes and mouse and human muscle tissues. Changes in chromatin accessibility and/or expression of genes resulted in distinct clusters of temporal molecular changes including transient, persistent, and delayed responses during hyperammonemia in myotubes. Known responses to hyperammonemia, including mitochondrial and oxidative dysfunction, protein homeostasis disruption, and oxidative stress pathway activation, were enriched in our datasets. During hyperammonemia, pathways that impact skeletal muscle structure and function that were consistently enriched were those that contribute to mitochondrial dysfunction, oxidative stress, and senescence. We made several novel observations, including an enrichment in antiapoptotic B-cell leukemia/lymphoma 2 family protein expression, increased calcium flux, and increased protein glycosylation in myotubes and muscle tissue upon hyperammonemia. Critical molecules in these pathways were validated experimentally. Human skeletal muscle from patients with cirrhosis displayed similar responses, establishing translational relevance. These data demonstrate complex molecular interactions during adaptive and maladaptive responses during the cellular stress response to hyperammonemia.
Collapse
Affiliation(s)
- Nicole Welch
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA; Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Shashi Shekhar Singh
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Avinash Kumar
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Saugato Rahman Dhruba
- Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas, USA
| | - Saurabh Mishra
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jinendiran Sekar
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Annette Bellar
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Amy H Attaway
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA; Department of Pulmonary Medicine, Cleveland Clinic, Cleveland, Ohio, USA
| | - Aruna Chelluboyina
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Belinda B Willard
- Proteomics Research Core Services, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Ling Li
- Proteomics Research Core Services, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Zhiguang Huo
- Department of Biostatistics, College of Public Health and Health Profession, University of Florida, Gainesville, Florida, USA
| | - Sadashiva S Karnik
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Karyn Esser
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Michelle S Longworth
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Yatrik M Shah
- Department of Molecular & Integrative Physiology and Department of Gastroenterology, University of Michigan, Ann Arbor, Michigan, USA
| | - Gangarao Davuluri
- Integrated Physiology and Molecular Metabolism, Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
| | - Ranadip Pal
- Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas, USA.
| | - Srinivasan Dasarathy
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA; Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio, USA.
| |
Collapse
|
30
|
Zhang Y, Kang JD, Zhao D, Ghosh SS, Wang Y, Tai Y, Gonzalez-Maeso J, Sikaroodi M, Gillevet PM, Lippman HR, Hylemon PB, Zhou H, Bajaj JS. Hepatic Branch Vagotomy Modulates the Gut-Liver-Brain Axis in Murine Cirrhosis. Front Physiol 2021; 12:702646. [PMID: 34248683 PMCID: PMC8268007 DOI: 10.3389/fphys.2021.702646] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/02/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Cirrhosis and hepatic encephalopathy (HE) are linked with an altered gut-liver-brain axis, however, the relative contribution of hepatic vagal innervation is unclear. We aimed to determine the impact of hepatic vagotomy on the gut microbiome, brain, and liver in murine cirrhosis. METHODS 10-15-week-old male C57BL/6 mice with and without hepatic vagotomy underwent carbon tetrachloride (CCl4) gavage for 8 weeks. Frontal cortex [inflammation, glial/microglial activation, BDNF (brain-derived neurotrophic factor)], liver [histology including inflammation and steatosis, fatty acid synthesis (sterol-responsive binding protein-1) SREBP-1, insulin-induced gene-2 (Insig2) and BDNF], and colonic mucosal microbiota (16srRNA microbial sequencing) were evaluated on sacrifice. Conventional mice with and without cirrhosis were compared to vagotomized counterparts. RESULTS Conventional control vs. cirrhosis: Cirrhosis resulted in dysbiosis, hepatic/neuro-inflammation with glial/microglial activation, and low brain BDNF vs. controls. Conventional control vs. vagotomy controls: Vagotomized control mice had a lower colonic dysbiosis than conventional mice but the rest of the hepatic/brain parameters were similar. Conventional cirrhosis vs. vagotomized cirrhosis: After vagotomy + cirrhosis, we found lower dysbiosis but continuing neuroinflammation in the absence of glial/microglial activation vs. conventional cirrhosis. Vagotomy + Cirrhosis groups showed higher hepatic steatosis due to higher SREBP1 and low Insig2 protein and altered activation of key genes involved in hepatic lipid metabolism and inflammation. BDNF levels in the brain were higher but low in the liver in vagotomy + cirrhosis, likely a protective mechanism. CONCLUSIONS Hepatic vagal innervation affects the gut microbial composition, hepatic inflammation and steatosis, and cortical inflammation and BDNF expression and could be a critical modulator of the gut-liver-brain axis with consequences for HE development.
Collapse
Affiliation(s)
- Yuan Zhang
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Jason D. Kang
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Derrick Zhao
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Siddartha S. Ghosh
- Division of Nephrology, Virginia Commonwealth University, Richmond, VA, United States
| | - Yanyan Wang
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Yunling Tai
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Javier Gonzalez-Maeso
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA, United States
| | - Masoumeh Sikaroodi
- Microbiome Analysis Center, George Mason University, Manassas, VA, United States
| | - Patrick M. Gillevet
- Microbiome Analysis Center, George Mason University, Manassas, VA, United States
| | - H. Robert Lippman
- Department of Pathology, Central Virginia Veterans Health Care System, Richmond, VA, United States
| | - Phillip B. Hylemon
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Huiping Zhou
- Division of Microbiology and Immunology, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| | - Jasmohan S. Bajaj
- Division of Gastroenterology, Hepatology, and Nutrition, Central Virginia Veterans Health Care System, Virginia Commonwealth University, Richmond, VA, United States
| |
Collapse
|
31
|
The Cerebral Effect of Ammonia in Brain Aging: Blood-Brain Barrier Breakdown, Mitochondrial Dysfunction, and Neuroinflammation. J Clin Med 2021; 10:jcm10132773. [PMID: 34202669 PMCID: PMC8268635 DOI: 10.3390/jcm10132773] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 06/23/2021] [Accepted: 06/23/2021] [Indexed: 12/14/2022] Open
Abstract
Aging occurs along with multiple pathological problems in various organs. The aged brain, especially, shows a reduction in brain mass, neuronal cell death, energy dysregulation, and memory loss. Brain aging is influenced by altered metabolites both in the systemic blood circulation and the central nervous system (CNS). High levels of ammonia, a natural by-product produced in the body, have been reported as contributing to inflammatory responses, energy metabolism, and synaptic function, leading to memory function in CNS. Ammonia levels in the brain also increase as a consequence of the aging process, ultimately leading to neuropathological problems in the CNS. Although many researchers have demonstrated that the level of ammonia in the body alters with age and results in diverse pathological alterations, the definitive relationship between ammonia and the aged brain is not yet clear. Thus, we review the current body of evidence related to the roles of ammonia in the aged brain. On the basis of this, we hypothesize that the modulation of ammonia level in the CNS may be a critical clinical point to attenuate neuropathological alterations associated with aging.
Collapse
|
32
|
Ochoa-Sanchez R, Tamnanloo F, Rose CF. Hepatic Encephalopathy: From Metabolic to Neurodegenerative. Neurochem Res 2021; 46:2612-2625. [PMID: 34129161 DOI: 10.1007/s11064-021-03372-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/31/2021] [Accepted: 06/03/2021] [Indexed: 12/15/2022]
Abstract
Hepatic encephalopathy (HE) is a neuropsychiatric syndrome of both acute and chronic liver disease. As a metabolic disorder, HE is considered to be reversible and therefore is expected to resolve following the replacement of the diseased liver with a healthy liver. However, persisting neurological complications are observed in up to 47% of transplanted patients. Several retrospective studies have shown that patients with a history of HE, particularly overt-HE, had persistent neurological complications even after liver transplantation (LT). These enduring neurological conditions significantly affect patient's quality of life and continue to add to the economic burden of chronic liver disease on health care systems. This review discusses the journey of the brain through the progression of liver disease, entering the invasive surgical procedure of LT and the conditions associated with the post-transplant period. In particular, it will discuss the vulnerability of the HE brain to peri-operative factors and post-LT conditions which may explain non-resolved neurological impairment following LT. In addition, the review will provide evidence; (i) supporting overt-HE impacts on neurological complications post-LT; (ii) that overt-HE leads to permanent neuronal injury and (iii) the pathophysiological role of ammonia toxicity on astrocyte and neuronal injury/damage. Together, these findings will provide new insights on the underlying mechanisms leading to neurological complications post-LT.
Collapse
Affiliation(s)
- Rafael Ochoa-Sanchez
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, 900, rue Saint-Denis Pavillon R, R08.422, Montreal, QC, H2X-0A9, Canada
| | - Farzaneh Tamnanloo
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, 900, rue Saint-Denis Pavillon R, R08.422, Montreal, QC, H2X-0A9, Canada
| | - Christopher F Rose
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, 900, rue Saint-Denis Pavillon R, R08.422, Montreal, QC, H2X-0A9, Canada.
| |
Collapse
|
33
|
Sah E, Krishnamurthy S, Ahmidouch MY, Gillispie GJ, Milligan C, Orr ME. The Cellular Senescence Stress Response in Post-Mitotic Brain Cells: Cell Survival at the Expense of Tissue Degeneration. Life (Basel) 2021; 11:229. [PMID: 33799628 PMCID: PMC7998276 DOI: 10.3390/life11030229] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/23/2021] [Accepted: 03/02/2021] [Indexed: 01/10/2023] Open
Abstract
In 1960, Rita Levi-Montalcini and Barbara Booker made an observation that transformed neuroscience: as neurons mature, they become apoptosis resistant. The following year Leonard Hayflick and Paul Moorhead described a stable replicative arrest of cells in vitro, termed "senescence". For nearly 60 years, the cell biology fields of neuroscience and senescence ran in parallel, each separately defining phenotypes and uncovering molecular mediators to explain the 1960s observations of their founding mothers and fathers, respectively. During this time neuroscientists have consistently observed the remarkable ability of neurons to survive. Despite residing in environments of chronic inflammation and degeneration, as occurs in numerous neurodegenerative diseases, often times the neurons with highest levels of pathology resist death. Similarly, cellular senescence (hereon referred to simply as "senescence") now is recognized as a complex stress response that culminates with a change in cell fate. Instead of reacting to cellular/DNA damage by proliferation or apoptosis, senescent cells survive in a stable cell cycle arrest. Senescent cells simultaneously contribute to chronic tissue degeneration by secreting deleterious molecules that negatively impact surrounding cells. These fields have finally collided. Neuroscientists have begun applying concepts of senescence to the brain, including post-mitotic cells. This initially presented conceptual challenges to senescence cell biologists. Nonetheless, efforts to understand senescence in the context of brain aging and neurodegenerative disease and injury emerged and are advancing the field. The present review uses pre-defined criteria to evaluate evidence for post-mitotic brain cell senescence. A closer interaction between neuro and senescent cell biologists has potential to advance both disciplines and explain fundamental questions that have plagued their fields for decades.
Collapse
Affiliation(s)
- Eric Sah
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
| | - Sudarshan Krishnamurthy
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Bowman Gray Center for Medical Education, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA
| | - Mohamed Y. Ahmidouch
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Departments of Biology and Chemistry, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Gregory J. Gillispie
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Carol Milligan
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA;
| | - Miranda E. Orr
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
- Salisbury VA Medical Center, Salisbury, NC 28144, USA
| |
Collapse
|
34
|
Sikora E, Bielak-Zmijewska A, Dudkowska M, Krzystyniak A, Mosieniak G, Wesierska M, Wlodarczyk J. Cellular Senescence in Brain Aging. Front Aging Neurosci 2021; 13:646924. [PMID: 33732142 PMCID: PMC7959760 DOI: 10.3389/fnagi.2021.646924] [Citation(s) in RCA: 128] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/02/2021] [Indexed: 12/25/2022] Open
Abstract
Aging of the brain can manifest itself as a memory and cognitive decline, which has been shown to frequently coincide with changes in the structural plasticity of dendritic spines. Decreased number and maturity of spines in aged animals and humans, together with changes in synaptic transmission, may reflect aberrant neuronal plasticity directly associated with impaired brain functions. In extreme, a neurodegenerative disease, which completely devastates the basic functions of the brain, may develop. While cellular senescence in peripheral tissues has recently been linked to aging and a number of aging-related disorders, its involvement in brain aging is just beginning to be explored. However, accumulated evidence suggests that cell senescence may play a role in the aging of the brain, as it has been documented in other organs. Senescent cells stop dividing and shift their activity to strengthen the secretory function, which leads to the acquisition of the so called senescence-associated secretory phenotype (SASP). Senescent cells have also other characteristics, such as altered morphology and proteostasis, decreased propensity to undergo apoptosis, autophagy impairment, accumulation of lipid droplets, increased activity of senescence-associated-β-galactosidase (SA-β-gal), and epigenetic alterations, including DNA methylation, chromatin remodeling, and histone post-translational modifications that, in consequence, result in altered gene expression. Proliferation-competent glial cells can undergo senescence both in vitro and in vivo, and they likely participate in neuroinflammation, which is characteristic for the aging brain. However, apart from proliferation-competent glial cells, the brain consists of post-mitotic neurons. Interestingly, it has emerged recently, that non-proliferating neuronal cells present in the brain or cultivated in vitro can also have some hallmarks, including SASP, typical for senescent cells that ceased to divide. It has been documented that so called senolytics, which by definition, eliminate senescent cells, can improve cognitive ability in mice models. In this review, we ask questions about the role of senescent brain cells in brain plasticity and cognitive functions impairments and how senolytics can improve them. We will discuss whether neuronal plasticity, defined as morphological and functional changes at the level of neurons and dendritic spines, can be the hallmark of neuronal senescence susceptible to the effects of senolytics.
Collapse
Affiliation(s)
- Ewa Sikora
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Anna Bielak-Zmijewska
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Magdalena Dudkowska
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Adam Krzystyniak
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Grazyna Mosieniak
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Malgorzata Wesierska
- Laboratory of Neuropsychology, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| | - Jakub Wlodarczyk
- Laboratory of Cell Biophysics, Nencki Institute of Experimental Biology, PAS, Warsaw, Poland
| |
Collapse
|
35
|
Regan JT, Mirczuk SM, Scudder CJ, Stacey E, Khan S, Worwood M, Powles T, Dennis-Beron JS, Ginley-Hidinger M, McGonnell IM, Volk HA, Strickland R, Tivers MS, Lawson C, Lipscomb VJ, Fowkes RC. Sensitivity of the Natriuretic Peptide/cGMP System to Hyperammonaemia in Rat C6 Glioma Cells and GPNT Brain Endothelial Cells. Cells 2021; 10:cells10020398. [PMID: 33672024 PMCID: PMC7919485 DOI: 10.3390/cells10020398] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/05/2021] [Accepted: 02/11/2021] [Indexed: 12/16/2022] Open
Abstract
C-type natriuretic peptide (CNP) is the major natriuretic peptide of the central nervous system and acts via its selective guanylyl cyclase-B (GC-B) receptor to regulate cGMP production in neurons, astrocytes and endothelial cells. CNP is implicated in the regulation of neurogenesis, axonal bifurcation, as well as learning and memory. Several neurological disorders result in toxic concentrations of ammonia (hyperammonaemia), which can adversely affect astrocyte function. However, the relationship between CNP and hyperammonaemia is poorly understood. Here, we examine the molecular and pharmacological control of CNP in rat C6 glioma cells and rat GPNT brain endothelial cells, under conditions of hyperammonaemia. Concentration-dependent inhibition of C6 glioma cell proliferation by hyperammonaemia was unaffected by CNP co-treatment. Furthermore, hyperammonaemia pre-treatment (for 1 h and 24 h) caused a significant inhibition in subsequent CNP-stimulated cGMP accumulation in both C6 and GPNT cells, whereas nitric-oxide-dependent cGMP accumulation was not affected. CNP-stimulated cGMP efflux from C6 glioma cells was significantly reduced under conditions of hyperammonaemia, potentially via a mechanism involving changed in phosphodiesterase expression. Hyperammonaemia-stimulated ROS production was unaffected by CNP but enhanced by a nitric oxide donor in C6 cells. Extracellular vesicle production from C6 cells was enhanced by hyperammonaemia, and these vesicles caused impaired CNP-stimulated cGMP signalling in GPNT cells. Collectively, these data demonstrate functional interaction between CNP signalling and hyperammonaemia in C6 glioma and GPNT cells, but the exact mechanisms remain to be established.
Collapse
Affiliation(s)
- Jacob T. Regan
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Samantha M. Mirczuk
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Christopher J. Scudder
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Emily Stacey
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Sabah Khan
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Michael Worwood
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Torinn Powles
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - J. Sebastian Dennis-Beron
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Matthew Ginley-Hidinger
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Imelda M. McGonnell
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Holger A. Volk
- Stiftung Tierärztliche Hochschule Hannover, Klinik für Kleintiere, Bünteweg, 930559 Hannover, Germany;
| | - Rhiannon Strickland
- Clinical Sciences & Services, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK; (R.S.); (V.J.L.)
| | - Michael S. Tivers
- Paragon Veterinary Referrals, Paragon Business Village Paragon Way, Red Hall Cres, Wakefield WF1 2DF, UK;
| | - Charlotte Lawson
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Victoria J. Lipscomb
- Clinical Sciences & Services, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK; (R.S.); (V.J.L.)
| | - Robert C. Fowkes
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
- Correspondence: ; Tel.: +44-207-468-1215
| |
Collapse
|
36
|
Clément MA, Bosoi CR, Oliveira MM, Tremblay M, Bémeur C, Rose CF. Bile-duct ligation renders the brain susceptible to hypotension-induced neuronal degeneration: Implications of ammonia. J Neurochem 2021; 157:561-573. [PMID: 33382098 DOI: 10.1111/jnc.15290] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 12/22/2020] [Accepted: 12/29/2020] [Indexed: 12/11/2022]
Abstract
Hepatic encephalopathy (HE) is a debilitating neurological complication of cirrhosis. By definition, HE is considered a reversible disorder, and therefore HE should resolve following liver transplantation (LT). However, persisting neurological complications are observed in as many as 47% of LT recipients. LT is an invasive surgical procedure accompanied by various perioperative factors such as blood loss and hypotension which could influence outcomes post-LT. We hypothesize that minimal HE (MHE) renders the brain frail and susceptible to hypotension-induced neuronal cell death. Six-week bile duct-ligated (BDL) rats with MHE and respective SHAM-controls were used. Several degrees of hypotension (mean arterial pressure of 30, 60 and 90 mm Hg) were induced via blood withdrawal from the femoral artery and maintained for 120 min. Brains were collected for neuronal cell count and apoptotic analysis. In a separate group, BDL rats were treated for MHE with the ammonia-lowering strategy ornithine phenylacetate (OP; MNK-6105), administered orally (1 g/kg) for 3 weeks before induction of hypotension. Hypotension 30 and 60 mm Hg (not 90 mm Hg) significantly decreased neuronal marker expression (NeuN) and cresyl violet staining in the frontal cortex compared to respective hypotensive SHAM-operated controls as well as non-hypotensive BDL rats. Neuronal degeneration was associated with an increase in cleaved caspase-3, suggesting the mechanism of cell death was apoptotic. OP treatment attenuated hyperammonaemia, improved anxiety and activity, and protected the brain against hypotension-induced neuronal cell death. Our findings demonstrate that rats with chronic liver disease and MHE are more susceptible to hypotension-induced neuronal cell degeneration. This highlights MHE at the time of LT is a risk factor for poor neurological outcome post-transplant and that treating for MHE pre-LT might reduce this risk.
Collapse
Affiliation(s)
- Marc-André Clément
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Canada
| | - Cristina R Bosoi
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Canada
| | - Mariana M Oliveira
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Canada
| | - Mélanie Tremblay
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Canada
| | - Chantal Bémeur
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Canada
| | - Christopher F Rose
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Canada
| |
Collapse
|
37
|
Luo S, Zhou ZM, Guo DJ, Li CM, Liu H, Wu XJ, Liang S, Zhao XY, Chen T, Sun D, Shi XL, Zhong WJ, Zhang W. Radiomics-based classification models for HBV-related cirrhotic patients with covert hepatic encephalopathy. Brain Behav 2021; 11:e01970. [PMID: 33236529 PMCID: PMC7882152 DOI: 10.1002/brb3.1970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 11/03/2020] [Accepted: 11/04/2020] [Indexed: 11/16/2022] Open
Abstract
INTRODUCTION The significant abnormalities of precuneus (PC), which are associated with brain dysfunction, have been identified in cirrhotic patients with covert hepatic encephalopathy (CHE). The present study aimed to apply radiomics analysis to identify the significant radiomic features in PC and their subregions, combine with clinical risk factors, then build and evaluate the classification models for CHE diagnosis. METHODS 106 HBV-related cirrhotic patients (54 had current CHE and 52 had non-CHE) underwent the three-dimensional T1-weighted imaging. For each participant, PC and their subregions were segmented and extracted a large number of radiomic features and then identified the features with significant discriminative power as the radiomics signature. The logistic regression analysis was employed to develop and evaluate the classification models, which are constructed using the radiomics signature and clinical risk factors. RESULTS The classification model (R-C model) achieved best diagnostic performance, which incorporated radiomics signature (4 radiomic features from right PC), venous blood ammonia, and the Child-Pugh stage. And the area under the receiver operating characteristic curve values (AUC), sensitivity, specificity, and accuracy values were 0.926, 1.000, 0.765, and 0.848, in the testing set. Application of the radiomics nomogram in the testing set still showed a good predictive accuracy. CONCLUSIONS This study presented the radiomic features of the right PC, as a potential image marker of CHE. The radiomics nomogram that incorporates the radiomics signature and clinical risk factors may facilitate the individualized prediction of CHE.
Collapse
Affiliation(s)
- Sha Luo
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhi-Ming Zhou
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Da-Jing Guo
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Chuan-Ming Li
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Huan Liu
- GE Healthcare Life Sciences, Shanghai, China
| | - Xiao-Jia Wu
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Shuang Liang
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiao-Yan Zhao
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ting Chen
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Dong Sun
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xin-Lin Shi
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wei-Jia Zhong
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wei Zhang
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
38
|
Rose CF, Amodio P, Bajaj JS, Dhiman RK, Montagnese S, Taylor-Robinson SD, Vilstrup H, Jalan R. Hepatic encephalopathy: Novel insights into classification, pathophysiology and therapy. J Hepatol 2020; 73:1526-1547. [PMID: 33097308 DOI: 10.1016/j.jhep.2020.07.013] [Citation(s) in RCA: 204] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 07/01/2020] [Accepted: 07/03/2020] [Indexed: 02/07/2023]
Abstract
Hepatic encephalopathy (HE) is a frequent and serious complication of both chronic liver disease and acute liver failure. HE manifests as a wide spectrum of neuropsychiatric abnormalities, from subclinical changes (mild cognitive impairment) to marked disorientation, confusion and coma. The clinical and economic burden of HE is considerable, and it contributes greatly to impaired quality of life, morbidity and mortality. This review will critically discuss the latest classification of HE, as well as the pathogenesis and pathophysiological pathways underlying the neurological decline in patients with end-stage liver disease. In addition, management strategies, diagnostic approaches, currently available therapeutic options and novel treatment strategies are discussed.
Collapse
Affiliation(s)
- Christopher F Rose
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montreal, Canada.
| | - Piero Amodio
- Department of Medicine, University of Padova, Padova, Italy
| | - Jasmohan S Bajaj
- Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and McGuire VA Medical Center, Richmond, Virginia, USA
| | - Radha Krishan Dhiman
- Department of Hepatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | | | - Simon D Taylor-Robinson
- Department of Surgery and Cancer, St. Mary's Hospital Campus, Imperial College London, London, United Kingdom
| | - Hendrik Vilstrup
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Denmark
| | - Rajiv Jalan
- Liver Failure Group, Institute for Liver and Digestive Health, University College London, Royal Free Campus, London, United Kingdom; European Foundation for the Study of Chronic Liver Failure, Barcelona, Spain.
| |
Collapse
|
39
|
Drews L, Zimmermann M, Westhoff P, Brilhaus D, Poss RE, Bergmann L, Wiek C, Brenneisen P, Piekorz RP, Mettler-Altmann T, Weber APM, Reichert AS. Ammonia inhibits energy metabolism in astrocytes in a rapid and glutamate dehydrogenase 2-dependent manner. Dis Model Mech 2020; 13:dmm047134. [PMID: 32917661 PMCID: PMC7657470 DOI: 10.1242/dmm.047134] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 09/02/2020] [Indexed: 01/02/2023] Open
Abstract
Astrocyte dysfunction is a primary factor in hepatic encephalopathy (HE) impairing neuronal activity under hyperammonemia. In particular, the early events causing ammonia-induced toxicity to astrocytes are not well understood. Using established cellular HE models, we show that mitochondria rapidly undergo fragmentation in a reversible manner upon hyperammonemia. Further, in our analyses, within a timescale of minutes, mitochondrial respiration and glycolysis were hampered, which occurred in a pH-independent manner. Using metabolomics, an accumulation of glucose and numerous amino acids, including branched chain amino acids, was observed. Metabolomic tracking of 15N-labeled ammonia showed rapid incorporation of 15N into glutamate and glutamate-derived amino acids. Downregulating human GLUD2 [encoding mitochondrial glutamate dehydrogenase 2 (GDH2)], inhibiting GDH2 activity by SIRT4 overexpression, and supplementing cells with glutamate or glutamine alleviated ammonia-induced inhibition of mitochondrial respiration. Metabolomic tracking of 13C-glutamine showed that hyperammonemia can inhibit anaplerosis of tricarboxylic acid (TCA) cycle intermediates. Contrary to its classical anaplerotic role, we show that, under hyperammonemia, GDH2 catalyzes the removal of ammonia by reductive amination of α-ketoglutarate, which efficiently and rapidly inhibits the TCA cycle. Overall, we propose a critical GDH2-dependent mechanism in HE models that helps to remove ammonia, but also impairs energy metabolism in mitochondria rapidly.
Collapse
Affiliation(s)
- Leonie Drews
- Institute for Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Marcel Zimmermann
- Institute for Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Philipp Westhoff
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
- Plant Metabolism and Metabolomics Laboratory, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Dominik Brilhaus
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
- Plant Metabolism and Metabolomics Laboratory, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Rebecca E Poss
- Institute for Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Laura Bergmann
- Institute for Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Constanze Wiek
- Department of Otorhinolaryngology and Head/Neck Surgery (ENT), Medical Faculty, Heinrich Heine University Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Peter Brenneisen
- Institute for Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Roland P Piekorz
- Institute for Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Tabea Mettler-Altmann
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
- Plant Metabolism and Metabolomics Laboratory, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Andreas P M Weber
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
- Plant Metabolism and Metabolomics Laboratory, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Andreas S Reichert
- Institute for Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| |
Collapse
|
40
|
Shang D, Hong Y, Xie W, Tu Z, Xu J. Interleukin-1β Drives Cellular Senescence of Rat Astrocytes Induced by Oligomerized Amyloid β Peptide and Oxidative Stress. Front Neurol 2020; 11:929. [PMID: 33013631 PMCID: PMC7493674 DOI: 10.3389/fneur.2020.00929] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/17/2020] [Indexed: 01/10/2023] Open
Abstract
Background: Alzheimer's disease (AD) is the leading cause of dementia. With no reliable treatment that delays or reverses the progress of AD, effective medical drugs, and interventions for AD treatment are in urgent need. Clinical success for patients thus relies on gaining a clearer understanding of AD pathogenesis to feed the development of novel and potent therapy strategies. It is well-established that inflammatory processes are involved in the pathology of AD, and recent studies implicated senescence of glial cells as an important player in the progression of AD. Methods: We did a preliminary screen in rat astrocytes for the five most abundant inflammatory factors in neuroinflammation, namely IL-1β, IL-6, IL-8, TGF-β1, and TNF-α, and found that IL-1β could efficiently induce cellular senescence. After that, SA-β-gal staining, immunofluorescence, ELISA, qRT-PCR, and immunoblotting were used to explore the underlying mechanism through which IL-1β mediates cellular senescence of rat astrocytes. Results: IL-1β-induced cellular senescence of rat astrocytes was accompanied by increased total and phosphorylated tau. Further experiments showed that both oligomerized amyloid β (Aβ) and H2O2 treatment can induce cellular senescence in rat astrocytes and increase the production and secretion of IL-1β from these cells. Subsequent mechanistic study revealed that activation of NLRP3 mediates Aβ and H2O2-induced maturation and secretion of IL-1β. Conclusion: Our results suggest that IL-1β mediates senescence in rat astrocytes induced by several common adverse stimuli in AD, implicating IL-1β and NLRP3 as valuable diagnostic biomarkers and therapeutic targets for AD.
Collapse
Affiliation(s)
- Dongsheng Shang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Yin Hong
- China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Wangwang Xie
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Zhigang Tu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Jun Xu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
41
|
Comparing the effects of whey and casein supplementation on nutritional status and immune parameters in patients with chronic liver disease: a randomised double-blind controlled trial. Br J Nutr 2020; 125:768-779. [PMID: 32807252 DOI: 10.1017/s0007114520003219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Protein supplementation may be beneficial for patients with chronic liver disease (CLD). This study compared the effects of whey protein isolate (WP) and casein (CA) supplementation on nutritional status and immune parameters of CLD patients who were randomly assigned to take 20 g of WP or CA twice per d as a supplement for 15 d. Body composition, muscle functionality and plasmatic immunomarkers were assessed before and after supplementation. Patients were also classified according to the model for end-stage liver disease (MELD) into less (MELD < 15) and more (MELD ≥ 15) severe disease groups. Malnutrition, determined by the Subjective Global Assessment at baseline, was observed in 57·4 % and 54·2 % of patients in the WP and CA groups, respectively (P = 0·649). Protein intake was lower at baseline in the WP group than in the CA group (P = 0·035), with no difference after supplementation (P = 0·410). Both the WP and CA MELD < 15 groups increased protein intake after supplementation according to the intragroup analysis. No differences were observed in body composition, muscle functionality, most plasma cytokines (TNF, IL-6, IL-1β and interferon-γ), immunomodulatory proteins (sTNFR1, sTNFR2, brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor) or immunomodulatory hormones (adiponectin, insulin and leptin) after supplementation in the WP groups at the two assessed moments. WP supplementation increased the levels of interferon-γ-induced protein-10/CXCL10 (P = 0·022), eotaxin-1/CCL11 (P = 0·031) and monocyte chemoattractant protein-1/CCL2 (P = 0·018) and decreased IL-5 (P = 0·027), including among those in the MELD ≥ 15 group, for whom IL-10 was also increased (P = 0·008). Thus, WP consumption by patients with CLD impacted the immunomodulatory responses when compared with CA with no impact on nutritional status.
Collapse
|
42
|
Papadopoulos D, Magliozzi R, Mitsikostas DD, Gorgoulis VG, Nicholas RS. Aging, Cellular Senescence, and Progressive Multiple Sclerosis. Front Cell Neurosci 2020; 14:178. [PMID: 32694983 PMCID: PMC7338849 DOI: 10.3389/fncel.2020.00178] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/22/2020] [Indexed: 12/12/2022] Open
Abstract
Aging is one of the most important risk factors for the development of several neurodegenerative diseases including progressive multiple sclerosis (MS). Cellular senescence (CS) is a key biological process underlying aging. Several stressors associated with aging and MS pathology, such as oxidative stress, mitochondrial dysfunction, cytokines and replicative exhaustion are known triggers of cellular senescence. Senescent cells exhibit stereotypical metabolic and functional changes, which include cell-cycle arrest and acquiring a pro-inflammatory phenotype secreting cytokines, growth factors, metalloproteinases and reactive oxygen species. They accumulate with aging and can convert neighboring cells to senescence in a paracrine manner. In MS, accelerated cellular senescence may drive disease progression by promoting chronic non-remitting inflammation, loss or altered immune, glial and neuronal function, failure of remyelination, impaired blood-brain barrier integrity and ultimately neurodegeneration. Here we discuss the evidence linking cellular senescence to the pathogenesis of MS and the putative role of senolytic and senomorphic agents as neuroprotective therapies in tackling disease progression.
Collapse
Affiliation(s)
- Dimitrios Papadopoulos
- Molecular Carcinogenesis Group, Laboratory of Histology and Embryology, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Roberta Magliozzi
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Verona, Italy
| | - Dimos D Mitsikostas
- First Department of Neurology, Aeginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Vassilis G Gorgoulis
- Molecular Carcinogenesis Group, Laboratory of Histology and Embryology, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Richard S Nicholas
- Department of Neuroinflammation and Neurodegeneration, Faculty of Medicine, Imperial College London, London, United Kingdom.,Department of Visual Neuroscience, Faculty of Brain Sciences, Institute of Ophthalmology, University College London, London, United Kingdom
| |
Collapse
|
43
|
Taha MS, Haghighi F, Stefanski A, Nakhaei-Rad S, Kazemein Jasemi NS, Al Kabbani MA, Görg B, Fujii M, Lang PA, Häussinger D, Piekorz RP, Stühler K, Ahmadian MR. Novel FMRP interaction networks linked to cellular stress. FEBS J 2020; 288:837-860. [PMID: 32525608 DOI: 10.1111/febs.15443] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 04/09/2020] [Accepted: 06/03/2020] [Indexed: 12/12/2022]
Abstract
Silencing of the fragile X mental retardation 1 (FMR1) gene and consequently lack of synthesis of FMR protein (FMRP) are associated with fragile X syndrome, which is one of the most prevalent inherited intellectual disabilities, with additional roles in increased viral infection, liver disease, and reduced cancer risk. FMRP plays critical roles in chromatin dynamics, RNA binding, mRNA transport, and mRNA translation. However, the underlying molecular mechanisms, including the (sub)cellular FMRP protein networks, remain elusive. Here, we employed affinity pull-down and quantitative LC-MS/MS analyses with FMRP. We identified known and novel candidate FMRP-binding proteins as well as protein complexes. FMRP interacted with 180 proteins, 28 of which interacted with its N terminus. Interaction with the C terminus of FMRP was observed for 102 proteins, and 48 proteins interacted with both termini. This FMRP interactome comprises known FMRP-binding proteins, including the ribosomal proteins FXR1P, NUFIP2, Caprin-1, and numerous novel FMRP candidate interacting proteins that localize to different subcellular compartments, including CARF, LARP1, LEO1, NOG2, G3BP1, NONO, NPM1, SKIP, SND1, SQSTM1, and TRIM28. Our data considerably expand the protein and RNA interaction networks of FMRP, which thereby suggest that, in addition to its known functions, FMRP participates in transcription, RNA metabolism, ribonucleoprotein stress granule formation, translation, DNA damage response, chromatin dynamics, cell cycle regulation, ribosome biogenesis, miRNA biogenesis, and mitochondrial organization. Thus, FMRP seems associated with multiple cellular processes both under normal and cell stress conditions in neuronal as well as non-neuronal cell types, as exemplified by its role in the formation of stress granules.
Collapse
Affiliation(s)
- Mohamed S Taha
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany.,Research on Children with Special Needs Department, Medical Research Branch, National Research Centre, Cairo, Egypt
| | - Fereshteh Haghighi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Anja Stefanski
- Molecular Proteomics Laboratory, Heinrich Heine-University, Düsseldorf, Germany
| | - Saeideh Nakhaei-Rad
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Neda S Kazemein Jasemi
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Mohamed Aghyad Al Kabbani
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Boris Görg
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty of the Heinrich Heine-University, Düsseldorf, Germany
| | - Masahiro Fujii
- Division of Virology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Phillip A Lang
- Department of Molecular Medicine II, Medical Faculty, Heinrich Heine-University, Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty of the Heinrich Heine-University, Düsseldorf, Germany
| | - Roland P Piekorz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| | - Kai Stühler
- Molecular Proteomics Laboratory, Heinrich Heine-University, Düsseldorf, Germany
| | - Mohammad R Ahmadian
- Institute of Biochemistry and Molecular Biology II, Medical Faculty of the Heinrich Heine University, Düsseldorf, Germany
| |
Collapse
|
44
|
Bobermin LD, Roppa RHA, Gonçalves CA, Quincozes-Santos A. Ammonia-Induced Glial-Inflammaging. Mol Neurobiol 2020; 57:3552-3567. [DOI: 10.1007/s12035-020-01985-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/08/2020] [Indexed: 12/13/2022]
|
45
|
Han X, Zhang T, Liu H, Mi Y, Gou X. Astrocyte Senescence and Alzheimer's Disease: A Review. Front Aging Neurosci 2020; 12:148. [PMID: 32581763 PMCID: PMC7297132 DOI: 10.3389/fnagi.2020.00148] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/01/2020] [Indexed: 01/10/2023] Open
Abstract
Astrocytes are the largest group of glial cells in the brain and participate in several essential functions of the central nervous system (CNS). Disruption of their normal physiological function can lead to metabolism disequilibrium and the pathology of CNS. As an important mechanism of aging, cellular senescence has been considered as a primary inducing factor of age-associated neurodegenerative disorders. Senescent astrocytes showed decreased normal physiological function and increased secretion of senescence-associated secretory phenotype (SASP) factors, which contribute to Aβ accumulation, tau hyperphosphorylation, and the deposition of neurofibrillary tangles (NFTs) in Alzheimer’s disease (AD). Astrocyte senescence also leads to a number of detrimental effects, including induced glutamate excitotoxicity, impaired synaptic plasticity, neural stem cell loss, and blood–brain barrier (BBB) dysfunction. In this review article, we have summarized the growing findings regarding astrocyte senescence and its putative role in the pathologic progress of AD. Additionally, we also focus on the significance of targeting astrocyte senescence as a novel and feasible therapeutic approach for AD.
Collapse
Affiliation(s)
- Xiaojuan Han
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Tianying Zhang
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Huanhuan Liu
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Yajing Mi
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Xingchun Gou
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| |
Collapse
|
46
|
Kerbert AJC, Jalan R. Recent advances in understanding and managing hepatic encephalopathy in chronic liver disease. F1000Res 2020; 9. [PMID: 32399191 PMCID: PMC7194462 DOI: 10.12688/f1000research.22183.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/21/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatic encephalopathy (HE) is a common, severe complication of advanced chronic liver disease (CLD) and has a devastating impact on the patient’s quality of life and prognosis. The neurotoxin ammonia and the presence of systemic and neurological inflammation are considered the key drivers of this neuropsychiatric syndrome. Treatment options available in routine clinical practice are limited, and the development of novel therapies is hampered owing to the complexity and heterogeneity of HE. This review article aims to outline the current understanding of the pathomechanisms of HE and the recent advances in the identification and development of novel therapeutic targets.
Collapse
Affiliation(s)
- Annarein J C Kerbert
- Institute for Liver and Digestive Health, University College London, Royal Free Campus, Rowland Hill Street, London, NW3 2PF, UK
| | - Rajiv Jalan
- Institute for Liver and Digestive Health, University College London, Royal Free Campus, Rowland Hill Street, London, NW3 2PF, UK
| |
Collapse
|
47
|
Sepehrinezhad A, Zarifkar A, Namvar G, Shahbazi A, Williams R. Astrocyte swelling in hepatic encephalopathy: molecular perspective of cytotoxic edema. Metab Brain Dis 2020; 35:559-578. [PMID: 32146658 DOI: 10.1007/s11011-020-00549-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/12/2020] [Indexed: 02/06/2023]
Abstract
Hepatic encephalopathy (HE) may occur in patients with liver failure. The most critical pathophysiologic mechanism of HE is cerebral edema following systemic hyperammonemia. The dysfunctional liver cannot eliminate circulatory ammonia, so its plasma and brain levels rise sharply. Astrocytes, the only cells that are responsible for ammonia detoxification in the brain, are dynamic cells with unique phenotypic properties that enable them to respond to small changes in their environment. Any pathological changes in astrocytes may cause neurological disturbances such as HE. Astrocyte swelling is the leading cause of cerebral edema, which may cause brain herniation and death by increasing intracranial pressure. Various factors may have a role in astrocyte swelling. However, the exact molecular mechanism of astrocyte swelling is not fully understood. This article discusses the possible mechanisms of astrocyte swelling which related to hyperammonia, including the possible roles of molecules like glutamine, lactate, aquaporin-4 water channel, 18 KDa translocator protein, glial fibrillary acidic protein, alanine, glutathione, toll-like receptor 4, epidermal growth factor receptor, glutamate, and manganese, as well as inflammation, oxidative stress, mitochondrial permeability transition, ATP depletion, and astrocyte senescence. All these agents and factors may be targeted in therapeutic approaches to HE.
Collapse
Affiliation(s)
- Ali Sepehrinezhad
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - Asadollah Zarifkar
- Shiraz Neuroscience Research Center and Department of Physiology, Shiraz University of Medical Sciences (SUMS), Shiraz, Iran
| | - Gholamreza Namvar
- Department of Neuroscience and Cognition, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Shahbazi
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran.
- Cellular and Molecular Research Center, Iran University of Medical Sciences (IUMS), Tehran, Iran.
| | - Roger Williams
- The Institute of Hepatology London and Foundation for Liver Research, 111 Coldharbour Lane, London, SE5 9NT, UK.
- Faculty of Life Sciences & Medicine, King's College London, London, UK.
| |
Collapse
|
48
|
Chen J, Wang H, He Z, Li T. Analysis of Risk Factors for Postoperative Delirium After Liver Transplantation. Neuropsychiatr Dis Treat 2020; 16:1645-1652. [PMID: 32753870 PMCID: PMC7343290 DOI: 10.2147/ndt.s254920] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 06/17/2020] [Indexed: 01/29/2023] Open
Abstract
PURPOSE The study aimed to analyze the incidence of postoperative delirium (POD) and associated risk factors after liver transplantation (LT). PATIENTS AND METHODS We identified and enrolled patients undergoing LT at the Second Xiangya Hospital, Central South University between August 2018 and May 2019. We abstracted their relevant clinical information and assigned the patients into a POD group and non-POD group to compare differences in clinical information. Risk factors of POD were analyzed using logistic regression. RESULTS A total of 159 LT patients were enrolled. Forty-two patients exhibited delirium (26.4%). Of the 42 with delirium, 33 (78.6%) had delirium within 3 days postoperatively and a median duration of 5 days (quartile 3-7 days). The results of binary logistic regression are as follows: preoperative ammonia (≥46 vs <46 μmol/L; OR 3.51, 95% CI [1.31-9.46], P<0.05), Model for End-Stage Liver Disease (MELD) score (≥15 vs.<15; OR 3.33, 95% CI [1.27-8.79], P<0.05), presence of hepatic encephalopathy (OR 3.30, 95% CI [1.20-9.07], P<0.05), aspartate aminotransferase (AST) on day 1 postoperatively (OR 1.33, 95% CI [1.06 -1.68], P<0.05), anhepatic period (OR 1.04, 95% CI [1.02 -1.06], P<0.01). The POD group had a longer intubation time (2925.0 vs 1410.0 min, P<0.01), ICU length of stay (6 vs 4 d, P<0.01) and increased medical costs (43.96 vs 33.74 ten thousand yuan, P<0.01). CONCLUSION The incidence of POD in LT patients is a significant clinical feature. Ammonia ≥46 μmol/l, MELD score ≥15, hepatic encephalopathy, anhepatic period, and AST at 1 day postoperatively were independent risk factors for POD.
Collapse
Affiliation(s)
- Junguo Chen
- Department of Organ Transplantation, The Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Hao Wang
- Department of Organ Transplantation, The Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Zhijun He
- Department of Organ Transplantation, The Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Ting Li
- Department of Organ Transplantation, The Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| |
Collapse
|
49
|
Görg B, Karababa A, Schütz E, Paluschinski M, Schrimpf A, Shafigullina A, Castoldi M, Bidmon HJ, Häussinger D. O-GlcNAcylation-dependent upregulation of HO1 triggers ammonia-induced oxidative stress and senescence in hepatic encephalopathy. J Hepatol 2019; 71:930-941. [PMID: 31279900 DOI: 10.1016/j.jhep.2019.06.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 06/24/2019] [Accepted: 06/27/2019] [Indexed: 01/18/2023]
Abstract
BACKGROUND & AIMS Cerebral oxidative stress plays an important role in the pathogenesis of hepatic encephalopathy (HE), but the underlying mechanisms are incompletely understood. Herein, we analyzed a role of heme oxygenase (HO)1, iron and NADPH oxidase 4 (Nox4) for the induction of oxidative stress and senescence in HE. METHODS Gene and protein expression in human post-mortem brain samples was analyzed by gene array and western blot analysis. Mechanisms and functional consequences of HO1 upregulation were studied in NH4Cl-exposed astrocytes in vitro by western blot, qPCR and super-resolution microscopy. RESULTS HO1 and the endoplasmic reticulum (ER) stress marker grp78 were upregulated, together with changes in the expression of multiple iron metabolism-related genes, in post-mortem brain samples from patients with liver cirrhosis and HE. NH4Cl elevated HO1 protein and mRNA in cultured astrocytes through glutamine synthetase (GS)-dependent upregulation of glutamine/fructose amidotransferases 1/2 (GFAT1/2), which blocked the transcription of the HO1-targeting miR326-3p in a O-GlcNAcylation dependent manner. Upregulation of HO1 by NH4Cl triggered ER stress and was associated with elevated levels of free ferrous iron and expression changes in iron metabolism-related genes, which were largely abolished after knockdown or inhibition of GS, GFAT1/2, HO1 or iron chelation. NH4Cl, glucosamine (GlcN) and inhibition of miR326-3p upregulated Nox4, while knockdown of Nox4, GS, GFAT1/2, HO1 or iron chelation prevented NH4Cl-induced RNA oxidation and astrocyte senescence. Elevated levels of grp78 and O-GlcNAcylated proteins were also found in brain samples from patients with liver cirrhosis and HE. CONCLUSION The present study identified glucosamine synthesis-dependent protein O-GlcNAcylation as a novel mechanism in the pathogenesis of HE that triggers oxidative and ER stress, as well as senescence, through upregulation of HO1 and Nox4. LAY SUMMARY Patients with liver cirrhosis frequently exhibit hyperammonemia and suffer from cognitive and motoric dysfunctions, which at least in part involve premature ageing of the astrocytes in the brain. This study identifies glucosamine and an O-GlcNAcylation-dependent disruption of iron homeostasis as novel triggers of oxidative stress, thereby mediating ammonia toxicity in the brain.
Collapse
Affiliation(s)
- Boris Görg
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany.
| | - Ayşe Karababa
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Elina Schütz
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Martha Paluschinski
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Alina Schrimpf
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Aygul Shafigullina
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Mirco Castoldi
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Hans J Bidmon
- C.&O. Vogt Institute for Brain Research, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| |
Collapse
|
50
|
Lu K, Zimmermann M, Görg B, Bidmon HJ, Biermann B, Klöcker N, Häussinger D, Reichert AS. Hepatic encephalopathy is linked to alterations of autophagic flux in astrocytes. EBioMedicine 2019; 48:539-553. [PMID: 31648987 PMCID: PMC6838440 DOI: 10.1016/j.ebiom.2019.09.058] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 02/07/2023] Open
Abstract
Background Hepatic encephalopathy (HE) is a severe neuropsychiatric syndrome caused by various types of liver failure resulting in hyperammonemia-induced dysfunction of astrocytes. It is unclear whether autophagy, an important pro-survival pathway, is altered in the brains of ammonia-intoxicated animals as well as in HE patients. Methods Using primary rat astrocytes, a co-culture model of primary mouse astrocytes and neurons, an in vivo rat HE model, and post mortem brain samples of liver cirrhosis patients with HE we analyzed whether and how hyperammonemia modulates autophagy. Findings We show that autophagic flux is efficiently inhibited after administration of ammonia in astrocytes. This occurs in a fast, reversible, time-, dose-, and ROS-dependent manner and is mediated by ammonia-induced changes in intralysosomal pH. Autophagic flux is also strongly inhibited in the cerebral cortex of rats after acute ammonium intoxication corroborating our results using an in vivo rat HE model. Transglutaminase 2 (TGM2), a factor promoting autophagy, is upregulated in astrocytes of in vitro- and in vivo-HE models as well as in post mortem brain samples of liver cirrhosis patients with HE, but not in patients without HE. LC3, a commonly used autophagy marker, is significantly increased in the brain of HE patients. Ammonia also modulated autophagy moderately in neuronal cells. We show that taurine, known to ameliorate several parameters caused by hyperammonemia in patients suffering from liver failure, is highly potent in reducing ammonia-induced impairment of autophagic flux. This protective effect of taurine is apparently not linked to inhibition of mTOR signaling but rather to reducing ammonia-induced ROS formation. Interpretation Our data support a model in which autophagy aims to counteract ammonia-induced toxicity, yet, as acidification of lysosomes is impaired, possible protective effects thereof, are hampered. We propose that modulating autophagy in astrocytes and/or neurons, e.g. by taurine, represents a novel strategy to treat liver diseases associated with HE. Funding Supported by the DFG, CRC974 “Communication and Systems Relevance in Liver Injury and Regeneration“, Düsseldorf (Project number 190586431) Projects A05 (DH), B04 (BG), B05 (NK), and B09 (ASR).
Collapse
Affiliation(s)
- Kaihui Lu
- Institute of Biochemistry and Molecular Biology I, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Marcel Zimmermann
- Institute of Biochemistry and Molecular Biology I, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Boris Görg
- Department of Gastroenterology, Hepatology and Infectious Diseases, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Hans-Jürgen Bidmon
- C. & O. Vogt Institute for Brain Research, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Barbara Biermann
- Institute of Neural and Sensory Physiology, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Nikolaj Klöcker
- Institute of Neural and Sensory Physiology, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Dieter Häussinger
- Department of Gastroenterology, Hepatology and Infectious Diseases, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology I, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany.
| |
Collapse
|