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Lokesh M, Bandaru LJM, Rajanna A, Dhayal VS, Challa S. M1 polarization induction by lead and amyloid peptides in microglial cells: Implications for neurodegeneration process. ENVIRONMENTAL TOXICOLOGY 2024; 39:4267-4277. [PMID: 38700421 DOI: 10.1002/tox.24305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/19/2024] [Accepted: 04/23/2024] [Indexed: 05/05/2024]
Abstract
Neurodegeneration in conditions like Alzheimer's and Parkinson's disease is influenced by genetic and environmental factors. This study explores the potential neurodegenerative effects of lead (Pb) toxicity and amyloid beta peptides (Aβp 1-40 and Aβp 25-35) by promoting M1 polarization in microglial cells. To this end, we investigated and observed that IC50 concentrations of Pb (22.8 μM) and Aβp 25-35(29.6 μM). Our results demonstrated significant Pb uptake (31.13% at 25 μM Pb) and increased intracellular ROS levels (77.1%) upon treatment with Pb in combination of both Aβp 1-40 and Aβp 25-35. Protein carbonylation significantly increased (73.12 nmol/mL) upon treatment with Pb in combination of both Aβp 1-40 and Aβp 25-35, indicating oxidative damage and compromised cellular defenses against oxidative stress along with elevated DNA oxidative damage (164.9 pg/mL of 8-OH-dG) upon treatment with Pb in combination with both Aβp 1-40 and Aβp 25-35. Microglial polarization showed elevated M1 markers (inducible nitric oxide synthase and cyclooxygenase 2) and reduced M2 markers (arginase-1 and cluster of differentiation 206), suggesting Pb's role in inducing neurodegenerative microglial polarization. These findings provide insights into the complex molecular events contributing to Pb-induced neurotoxicity and neurodegenerative diseases.
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Affiliation(s)
- Murumulla Lokesh
- Cell Biology Division, National Institute of Nutrition, Hyderabad, India
| | | | - Ajumeera Rajanna
- Cell Biology Division, National Institute of Nutrition, Hyderabad, India
| | | | - Suresh Challa
- Cell Biology Division, National Institute of Nutrition, Hyderabad, India
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2
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Zhao J, Wei M, Guo M, Wang M, Niu H, Xu T, Zhou Y. GSK3: A potential target and pending issues for treatment of Alzheimer's disease. CNS Neurosci Ther 2024; 30:e14818. [PMID: 38946682 PMCID: PMC11215492 DOI: 10.1111/cns.14818] [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: 04/22/2024] [Revised: 05/21/2024] [Accepted: 05/27/2024] [Indexed: 07/02/2024] Open
Abstract
Glycogen synthase kinase-3 (GSK3), consisting of GSK3α and GSK3β subtypes, is a complex protein kinase that regulates numerous substrates. Research has observed increased GSK3 expression in the brains of Alzheimer's disease (AD) patients and models. AD is a neurodegenerative disorder with diverse pathogenesis and notable cognitive impairments, characterized by Aβ aggregation and excessive tau phosphorylation. This article provides an overview of GSK3's structure and regulation, extensively analyzing its relationship with AD factors. GSK3 overactivation disrupts neural growth, development, and function. It directly promotes tau phosphorylation, regulates amyloid precursor protein (APP) cleavage, leading to Aβ formation, and directly or indirectly triggers neuroinflammation and oxidative damage. We also summarize preclinical research highlighting the inhibition of GSK3 activity as a primary therapeutic approach for AD. Finally, pending issues like the lack of highly specific and affinity-driven GSK3 inhibitors, are raised and expected to be addressed in future research. In conclusion, GSK3 represents a target in AD treatment, filled with hope, challenges, opportunities, and obstacles.
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Affiliation(s)
- Jiahui Zhao
- School of Basic Medical SciencesZhejiang Chinese Medical UniversityHangzhouChina
| | - Mengying Wei
- College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
- Future Health Laboratory, Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxingChina
| | - Minsong Guo
- College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
- Cangnan County Qiushi Innovation Research Institute of Traditional Chinese MedicineWenzhouChina
| | - Mengyao Wang
- School of Basic Medical SciencesZhejiang Chinese Medical UniversityHangzhouChina
| | - Hongxia Niu
- School of Basic Medical SciencesZhejiang Chinese Medical UniversityHangzhouChina
- Key Laboratory of Blood‐stasis‐toxin Syndrome of Zhejiang ProvinceHangzhouChina
| | - Tengfei Xu
- College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
- Cangnan County Qiushi Innovation Research Institute of Traditional Chinese MedicineWenzhouChina
| | - Yuan Zhou
- School of Basic Medical SciencesZhejiang Chinese Medical UniversityHangzhouChina
- Key Laboratory of Blood‐stasis‐toxin Syndrome of Zhejiang ProvinceHangzhouChina
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3
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Fu X, Wang Z. DHCR24 in Tumor Diagnosis and Treatment: A Comprehensive Review. Technol Cancer Res Treat 2024; 23:15330338241259780. [PMID: 38847653 PMCID: PMC11162140 DOI: 10.1177/15330338241259780] [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] [Indexed: 06/10/2024] Open
Abstract
As an important nutrient in the human body, cholesterol can not only provide structural components for the body's cells, but also can be transformed into a variety of active substances to regulate cell signaling pathways. As an important cholesterol synthase, DHCR24 participates in important regulatory processes in the body. The application of DHCR24 in tumor clinical diagnosis and treatment also attracts much attention. This article reviews the structure and regulatory characteristics of DHCR24, and the research of DHCR24 on tumor progression. We summarize the possible mechanisms of DHCR24 promoting tumor progression through reactive oxygen species (ROS), p53, Ras and PI3K-AKT pathways. Through our review, we hope to provide more research ideas and reference value for the application of DHCR24 in tumor prevention and treatment.
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Affiliation(s)
- Xin Fu
- Department of Gynecologic Oncology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- Tianjin's Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Zhaosong Wang
- National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- Tianjin's Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- Laboratory Animal Center, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
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4
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Zheng Y, Zhang X, Zhang R, Wang Z, Gan J, Gao Q, Yang L, Xu P, Jiang X. Inflammatory signaling pathways in the treatment of Alzheimer's disease with inhibitors, natural products and metabolites (Review). Int J Mol Med 2023; 52:111. [PMID: 37800614 PMCID: PMC10558228 DOI: 10.3892/ijmm.2023.5314] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/11/2023] [Indexed: 10/07/2023] Open
Abstract
The intricate nature of Alzheimer's disease (AD) pathogenesis poses a persistent obstacle to drug development. In recent times, neuroinflammation has emerged as a crucial pathogenic mechanism of AD, and the targeting of inflammation has become a viable approach for the prevention and management of AD. The present study conducted a comprehensive review of the literature between October 2012 and October 2022, identifying a total of 96 references, encompassing 91 distinct pharmaceuticals that have been investigated for their potential impact on AD by inhibiting neuroinflammation. Research has shown that pharmaceuticals have the potential to ameliorate AD by reducing neuroinflammation mainly through regulating inflammatory signaling pathways such as NF‑κB, MAPK, NLRP3, PPARs, STAT3, CREB, PI3K/Akt, Nrf2 and their respective signaling pathways. Among them, tanshinone IIA has been extensively studied for its anti‑inflammatory effects, which have shown significant pharmacological properties and can be applied clinically. Thus, it may hold promise as an effective drug for the treatment of AD. The present review elucidated the inflammatory signaling pathways of pharmaceuticals that have been investigated for their therapeutic efficacy in AD and elucidates their underlying mechanisms. This underscores the auspicious potential of pharmaceuticals in ameliorating AD by impeding neuroinflammation.
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Affiliation(s)
| | | | - Ruifeng Zhang
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Ziyu Wang
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Jiali Gan
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Qing Gao
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Lin Yang
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Pengjuan Xu
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Xijuan Jiang
- Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
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5
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Feng X, Li M, Lin Z, Lu Y, Zhuang Y, Lei J, Liu X, Zhao H. Tetramethylpyrazine promotes axonal remodeling and modulates microglial polarization via JAK2-STAT1/3 and GSK3-NFκB pathways in ischemic stroke. Neurochem Int 2023; 170:105607. [PMID: 37657766 DOI: 10.1016/j.neuint.2023.105607] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/18/2023] [Accepted: 08/30/2023] [Indexed: 09/03/2023]
Abstract
Ischemic stroke results in demyelination that underlies neurological disfunction. Promoting oligodendrogenesis will rescue the injured axons and accelerate remyelination after stroke. Microglia react to ischemia/hypoxia and polarize to M1/M2 phenotypes influencing myelin injury and repair. Tetramethylpyrazine (TMP) has neuroprotective effects in treating cerebrovascular disorders. This study aims to evaluate whether TMP promotes the renovation of damaged brain tissues especially on remyelination and modulates microglia phenotypes following ischemic stroke. Here magnetic resonance imaging (MRI)-diffusion tensor imaging (DTI) and histopathological evaluation are performed to characterize the process of demyelination and remyelination. Immunofluorescence staining is used to prove oligodendrogenesis and microglial polarization. Western blotting is conducted to examine interleukin (IL)-6, IL-10, transforming growth factor β (TGF-β) and Janus protein tyrosine kinase (JAK) 2-signal transducer and activator of transcription (STAT) 1/3-glycogen synthase kinase (GSK) 3-nuclear transcription factor κB (NFκB) signals. Results show TMP alleviates the injury of axons and myelin sheath, increases NG2+, Ki67+/NG2+, CNPase+, Ki67+/CNPase+, Iba1+/Arg-1+ cells and decreases Iba1+ and Iba1+/CD16+ cells in periinfarctions of rats. Particularly, TMP downregulates IL-6 and upregulates IL-10 and TGF-β expressions, besides, enhances JAK2-STAT3 and suppresses STAT1-GSK3-NFκB activation in middle cerebral artery occlusion (MCAo) rats. Then we demonstrate that TMP reverses M1/M2 phenotype via JAK2-STAT1/3 and GSK3-NFκB pathways in lipopolysaccharide (LPS) plus interferon-γ (IFN-γ)-stimulated BV2 microglia. Blocking JAK2 with AG490 counteracts TMP's facilitation on M2 polarization of microglia. This study warrants the promising therapy for stroke with TMP treatment.
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Affiliation(s)
- Xuefeng Feng
- Department of Pharmacy, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, 230031, China; School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China
| | - Mingcong Li
- School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research, Beijing, 100069, China
| | - Ziyue Lin
- School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research, Beijing, 100069, China
| | - Yun Lu
- School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research, Beijing, 100069, China
| | - Yuming Zhuang
- School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research, Beijing, 100069, China
| | - Jianfeng Lei
- Medical Imaging Laboratory of Core Facility Center, Capital Medical University, Beijing, 100069, China
| | - Xiaonan Liu
- Department of Laboratory Animal, Capital Medical University, Beijing, 100069, China
| | - Hui Zhao
- School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research, Beijing, 100069, China.
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6
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Li H, Zhang C, Zhou Y, Deng Y, Zheng X, Xue X. Neurovascular protection of alisol A on cerebral ischemia mice through activating the AKT/GSK3β pathway. Aging (Albany NY) 2023; 15:11639-11653. [PMID: 37889534 PMCID: PMC10637819 DOI: 10.18632/aging.205151] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 10/02/2023] [Indexed: 10/28/2023]
Abstract
Alisol A, a triterpene isolated from Alisma Orientale, has been shown to exhibit anti-inflammatory effects and vascular protection. This study was designed to observe the effect of alisol A on cerebral ischemia (CI)-induced neurovascular dysfunction in the hippocampus and to further explore the potential mechanisms. The results showed that alisol A treatment improved the neurological deficits and cognitive impairment of CI mice. Alisol A reduced gliosis and improved neuronal/glial metabolism. Accordingly, alisol A inhibited inflammatory factors IL-6 and IL-1β induced by overactivation of astrocytes and microglia, thus protecting the neurovasculature. Furthermore, alisol A promoted the survival of neurons by decreasing the ratio of Bax/Bcl-2, and protected brain microvascular endothelial cells (BMECs) by upregulating the expression of ZO-1, Occludin and CD31. The phosphorylation of protein kinase B (AKT) and glycogen synthase kinase 3β (GSK3β) increased after treatment with alisol A. To explore the underlying mechanism, AKT was inhibited. As expected, the neurovascular protection of alisol A above was eliminated by AKT inhibition. The present study primarily suggested that alisol A could exert neurovascular protection in the hippocampus of CI mice by activating the AKT/GSK3β pathway and may potentially be used for the treatment of CI.
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Affiliation(s)
- Huihong Li
- The Affiliated Rehabilitation Hospital, Fujian University of Traditional Chinese Medicine, Fuzhou, China
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Caiyun Zhang
- The Zhangpu Hospital of Traditional Chinese Medicine, Zhangzhou, Fujian, China
| | - Yangjie Zhou
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Yunfei Deng
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Xiaoqing Zheng
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Xiehua Xue
- The Affiliated Rehabilitation Hospital, Fujian University of Traditional Chinese Medicine, Fuzhou, China
- Key Laboratory of Cognitive Rehabilitation of Fujian Province, Fuzhou, China
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7
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Liu GZ, Niu TT, Yu Q, Xu BL, Li XQ, Yuan BY, Yuan GB, Yang TT, Li HQ, Sun Y. Ginkgolide attenuates memory impairment and neuroinflammation by suppressing the NLRP3/caspase-1 pathway in Alzheimer's disease. Aging (Albany NY) 2023; 15:10237-10252. [PMID: 37793010 PMCID: PMC10599747 DOI: 10.18632/aging.205072] [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: 04/03/2023] [Accepted: 07/17/2023] [Indexed: 10/06/2023]
Abstract
The NLRP3 inflammasome is involved in the neuroinflammatory pathway of Alzheimer's disease (AD). The aim of this study is to explore the roles and underlying mechanisms of ginkgolide (Baiyu®) on amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic mice and a murine microglial cell line, BV-2. In the present study, the APP/PS1 mice were administered with ginkgolide, followed by a Morris water maze test. The mice were then euthanized to obtain brain tissue for histological and Aβ analysis. Additionally, BV-2 cells were pretreated with ginkgolide and then incubated with Aβ1-42 peptide. NLRP3, ASC, and caspase-1 mRNA and protein expression in brain tissue of mice and BV-2 cells were quantified by real-time PCR and western blotting, as well as reactive oxygen species (ROS) production, interleukin (IL)-1β and IL-18 levels by lucigenin technique and ELISA. Compared with the APP/PS1 mice, ginkgolide-treated mice demonstrated the shortened escape latency, reduced plaques, less inflammatory cell infiltration and neuron loss in the hippocampi of APP/PS1 mice. The levels of NLRP3, ASC, caspase-1, ROS, IL-1β, and IL-18 were also decreased in the brain tissue of APP/PS1 mice or Aβ1-42-treated BV-2 cells following ginkgolide treatment. Ginkgolide exerted protective effects on AD, at least partly by inactivating the NLRP3/caspase-1 pathway.
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Affiliation(s)
- Guang-Zhi Liu
- Department of Neurology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Tian-Tong Niu
- Department of Neurology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Qian Yu
- Beijing D.A. Medical Laboratory, Beijing 102600, China
| | - Bao-Lei Xu
- National Clinical Research Center for Geriatric Diseases, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Xiao-Qing Li
- Department of Neurology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Bo-Yi Yuan
- Department of Neurology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Guo-Bin Yuan
- Department of Neurology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Ting-Ting Yang
- Department of Neurology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Hui-Qin Li
- Research and Development Centre, Chengdu Baiyu Pharmaceutical Co., Ltd., Chengdu 611130, China
| | - Yi Sun
- Research and Development Centre, Chengdu Baiyu Pharmaceutical Co., Ltd., Chengdu 611130, China
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8
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Luo L, Guo Y, Chen L, Zhu J, Li C. Crosstalk between cholesterol metabolism and psoriatic inflammation. Front Immunol 2023; 14:1124786. [PMID: 37234169 PMCID: PMC10206135 DOI: 10.3389/fimmu.2023.1124786] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 04/26/2023] [Indexed: 05/27/2023] Open
Abstract
Psoriasis is a chronic autoinflammatory skin disease associated with multiple comorbidities, with a prevalence ranging from 2 to 3% in the general population. Decades of preclinical and clinical studies have revealed that alterations in cholesterol and lipid metabolism are strongly associated with psoriasis. Cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-17), which are important in the pathogenesis of psoriasis, have been shown to affect cholesterol and lipid metabolism. Cholesterol metabolites and metabolic enzymes, on the other hand, influence not only the biofunction of keratinocytes (a primary type of cell in the epidermis) in psoriasis, but also the immune response and inflammation. However, the relationship between cholesterol metabolism and psoriasis has not been thoroughly reviewed. This review mainly focuses on cholesterol metabolism disturbances in psoriasis and their crosstalk with psoriatic inflammation.
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Affiliation(s)
- Lingling Luo
- Department of Dermatology, Hospital for Skin Disease, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Youming Guo
- Department of Dermatology, Hospital for Skin Disease, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Lihao Chen
- Department of Dermatology, Hospital for Skin Disease, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Jing Zhu
- Department of Dermatology, Hospital for Skin Disease, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
| | - Chengrang Li
- Department of Dermatology, Hospital for Skin Disease, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
- Department of Dermatology, Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and Sexually Transmitted Infections, Nanjing, Jiangsu, China
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9
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Samim Khan S, Janrao S, Srivastava S, Bala Singh S, Vora L, Kumar Khatri D. GSK-3β: An exuberating neuroinflammatory mediator in Parkinson's disease. Biochem Pharmacol 2023; 210:115496. [PMID: 36907495 DOI: 10.1016/j.bcp.2023.115496] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/02/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023]
Abstract
Neuroinflammation is a critical degradative condition affecting neurons in the brain. Progressive neurodegenerative conditions such as Alzheimer's disease and Parkinson's disease (PD) have been strongly linked to neuroinflammation. The trigger point for inflammatory conditions in the cells and body is the physiological immune system. The immune response mediated by glial cells and astrocytes can rectify the physiological alterations occurring in the cell for the time being but prolonged activation leads to pathological progression. The proteins mediating such an inflammatory response, as per the available literature, are undoubtedly GSK-3β, NLRP3, TNF, PPARγ, and NF-κB, along with a few other mediatory proteins. NLRP3 inflammasome is undeniably a principal instigator of the neuroinflammatory response, but the regulatory pathways controlling its activation are still unclear, besides less clarity for the interplay between different inflammatory proteins. Recent reports have suggested the involvement of GSK-3β in regulating NLRP3 activation, but the exact mechanistic pathway remains vague. In the current review, we attempt to provide an elaborate description of crosstalk between inflammatory markers and GSK-3β mediated neuroinflammation progression, linking it to regulatory transcription factors and posttranslational modification of proteins. The recent clinical therapeutic advances targeting these proteins are also discussed in parallel to provide a comprehensive view of the progress made in PD management and lacunas still existing in the field.
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Affiliation(s)
- Sabiya Samim Khan
- Molecular & Cellular Neuroscience Lab, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Telangana 500037, India
| | - Sushmita Janrao
- Molecular & Cellular Neuroscience Lab, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Telangana 500037, India
| | - Saurabh Srivastava
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Telangana 500037, India.
| | - Shashi Bala Singh
- Molecular & Cellular Neuroscience Lab, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Telangana 500037, India.
| | - Lalitkumar Vora
- School of Pharmacy, Queen's University Belfast, 97, Lisburn Road, Belfast BT9 7BL, UK.
| | - Dharmendra Kumar Khatri
- Molecular & Cellular Neuroscience Lab, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hyderabad, Telangana 500037, India.
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10
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Theerasri A, Janpaijit S, Tencomnao T, Prasansuklab A. Beyond the classical amyloid hypothesis in Alzheimer's disease: Molecular insights into current concepts of pathogenesis, therapeutic targets, and study models. WIREs Mech Dis 2023; 15:e1591. [PMID: 36494193 DOI: 10.1002/wsbm.1591] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 11/19/2022] [Accepted: 11/21/2022] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is one of the progressive neurodegenerative disorders and the most common cause of dementia in the elderly worldwide causing difficulties in the daily life of the patient. AD is characterized by the aberrant accumulation of β-amyloid plaques and tau protein-containing neurofibrillary tangles (NFTs) in the brain giving rise to neuroinflammation, oxidative stress, synaptic failure, and eventual neuronal cell death. The total cost of care in AD treatment and related health care activities is enormous and pharmaceutical drugs approved by Food and Drug Administration have not manifested sufficient efficacy in protection and therapy. In recent years, there are growing studies that contribute a fundamental understanding to AD pathogenesis, AD-associated risk factors, and pharmacological intervention. However, greater molecular process-oriented research in company with suitable experimental models is still of the essence to enhance the prospects for AD therapy and cell lines as a disease model are still the major part of this milestone. In this review, we provide an insight into molecular mechanisms, particularly the recent concept in gut-brain axis, vascular dysfunction and autophagy, and current models used in the study of AD. Here, we emphasized the importance of therapeutic strategy targeting multiple mechanisms together with utilizing appropriate models for the discovery of novel effective AD therapy. This article is categorized under: Neurological Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
- Atsadang Theerasri
- Graduate Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand.,Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
| | - Sakawrat Janpaijit
- Graduate Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand.,Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
| | - Tewin Tencomnao
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand.,Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Anchalee Prasansuklab
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand.,College of Public Health Sciences, Chulalongkorn University, Bangkok, Thailand
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11
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Raas Q, Tawbeh A, Tahri-Joutey M, Gondcaille C, Keime C, Kaiser R, Trompier D, Nasser B, Leoni V, Bellanger E, Boussand M, Hamon Y, Benani A, Di Cara F, Truntzer C, Cherkaoui-Malki M, Andreoletti P, Savary S. Peroxisomal defects in microglial cells induce a disease-associated microglial signature. Front Mol Neurosci 2023; 16:1170313. [PMID: 37138705 PMCID: PMC10149961 DOI: 10.3389/fnmol.2023.1170313] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/27/2023] [Indexed: 05/05/2023] Open
Abstract
Microglial cells ensure essential roles in brain homeostasis. In pathological condition, microglia adopt a common signature, called disease-associated microglial (DAM) signature, characterized by the loss of homeostatic genes and the induction of disease-associated genes. In X-linked adrenoleukodystrophy (X-ALD), the most common peroxisomal disease, microglial defect has been shown to precede myelin degradation and may actively contribute to the neurodegenerative process. We previously established BV-2 microglial cell models bearing mutations in peroxisomal genes that recapitulate some of the hallmarks of the peroxisomal β-oxidation defects such as very long-chain fatty acid (VLCFA) accumulation. In these cell lines, we used RNA-sequencing and identified large-scale reprogramming for genes involved in lipid metabolism, immune response, cell signaling, lysosome and autophagy, as well as a DAM-like signature. We highlighted cholesterol accumulation in plasma membranes and observed autophagy patterns in the cell mutants. We confirmed the upregulation or downregulation at the protein level for a few selected genes that mostly corroborated our observations and clearly demonstrated increased expression and secretion of DAM proteins in the BV-2 mutant cells. In conclusion, the peroxisomal defects in microglial cells not only impact on VLCFA metabolism but also force microglial cells to adopt a pathological phenotype likely representing a key contributor to the pathogenesis of peroxisomal disorders.
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Affiliation(s)
- Quentin Raas
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
| | - Ali Tawbeh
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
| | - Mounia Tahri-Joutey
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
- Laboratory of Biochemistry, Neurosciences, Natural Resources and Environment, Faculty of Sciences and Techniques, University Hassan I, Settat, Morocco
| | | | - Céline Keime
- Plateforme GenomEast, IGBMC, CNRS UMR 7104, Inserm U1258, University of Strasbourg, Illkirch, France
| | - Romain Kaiser
- Plateforme GenomEast, IGBMC, CNRS UMR 7104, Inserm U1258, University of Strasbourg, Illkirch, France
| | - Doriane Trompier
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
| | - Boubker Nasser
- Laboratory of Biochemistry, Neurosciences, Natural Resources and Environment, Faculty of Sciences and Techniques, University Hassan I, Settat, Morocco
| | - Valerio Leoni
- Laboratory of Clinical Biochemistry, Hospital of Desio, ASST-Brianza and Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Emma Bellanger
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Maud Boussand
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Yannick Hamon
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Alexandre Benani
- Centre des Sciences du Goût et de l’Alimentation, CNRS, INRAE, Institut Agro Dijon, University of Bourgogne Franche-Comté, Dijon, France
| | - Francesca Di Cara
- Department of Microbiology and Immunology, IWK Health Centre, Dalhousie University, Halifax, NS, Canada
| | - Caroline Truntzer
- Platform of Transfer in Biological Oncology, Georges François Leclerc Cancer Center–Unicancer, Dijon, France
| | | | | | - Stéphane Savary
- Laboratoire Bio-PeroxIL EA7270, University of Bourgogne, Dijon, France
- *Correspondence: Stéphane Savary,
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12
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Huang W, Xia Q, Zheng F, Zhao X, Ge F, Xiao J, Liu Z, Shen Y, Ye K, Wang D, Li Y. Microglia-Mediated Neurovascular Unit Dysfunction in Alzheimer's Disease. J Alzheimers Dis 2023; 94:S335-S354. [PMID: 36683511 PMCID: PMC10473143 DOI: 10.3233/jad-221064] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2022] [Indexed: 01/21/2023]
Abstract
The neurovascular unit (NVU) is involved in the pathological changes in Alzheimer's disease (AD). The NVU is a structural and functional complex that maintains microenvironmental homeostasis and metabolic balance in the central nervous system. As one of the most important components of the NVU, microglia not only induce blood-brain barrier breakdown by promoting neuroinflammation, the infiltration of peripheral white blood cells and oxidative stress but also mediate neurovascular uncoupling by inducing mitochondrial dysfunction in neurons, abnormal contraction of cerebral vessels, and pericyte loss in AD. In addition, microglia-mediated dysfunction of cellular components in the NVU, such as astrocytes and pericytes, can destroy the integrity of the NVU and lead to NVU impairment. Therefore, we review the mechanisms of microglia-mediated NVU dysfunction in AD. Furthermore, existing therapeutic advancements aimed at restoring the function of microglia and the NVU in AD are discussed. Finally, we predict the role of pericytes in microglia-mediated NVU dysfunction in AD is the hotspot in the future.
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Affiliation(s)
- Wenhao Huang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Qing Xia
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Feifei Zheng
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Xue Zhao
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Fangliang Ge
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Jiaying Xiao
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Zijie Liu
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Yingying Shen
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Ke Ye
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Dayong Wang
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
- Basic Medical Institute, Heilongjiang Medical Science Academy, Harbin, Heilongjiang Province, China
- Translational Medicine Center of Northern China, Harbin, Heilongjiang Province, China
- Key Laboratory of Heilongjiang Province for Genetically Modified Animals, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Yanze Li
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, Heilongjiang Province, China
- Basic Medical Institute, Heilongjiang Medical Science Academy, Harbin, Heilongjiang Province, China
- Translational Medicine Center of Northern China, Harbin, Heilongjiang Province, China
- Key Laboratory of Heilongjiang Province for Genetically Modified Animals, Harbin Medical University, Harbin, Heilongjiang Province, China
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13
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Yu G, Yu H, Yang Q, Wang J, Fan H, Liu G, Wang L, Bello BK, Zhao P, Zhang H, Dong J. Vibrio harveyi infections induce production of proinflammatory cytokines in murine peritoneal macrophages via activation of p38 MAPK and NF-κB pathways, but reversed by PI3K/AKT pathways. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 127:104292. [PMID: 34656643 DOI: 10.1016/j.dci.2021.104292] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 10/09/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
Vibrio harveyi is a zoonotic pathogen that can infect humans through wounds and cause severe inflammatory responses. Previous studies have reported that the Toll like receptors (TLR) mediated MAPK, AKT and NF-κB signaling pathways are involved in innate immune system resistance to pathogen invasion. However, the molecular mechanism of these pathways, as well as their involvement in V. harveyi infection remains elusive. This study established a V. harveyi infection model using murine peritoneal macrophages (PMs). Various techniques, including western blotting, ELISA, RT-qPCR, immunofluorescence, inhibition assays, were used to explore the roles of TLRs, MAPK, AKT and NF-κB signaling pathways in V. harveyi-induced inflammatory responses. ELISA assays showed that V. harveyi infection triggered proinflammatory cytokines secretion in PMs. RT-qPCR and inhibition assays showed that TLR2 participated in V. harveyi infection and up-regulated the proinflammatory cytokines secretion in murine PMs. Western blotting data showed that the phosphorylation of p38, JNK, AKT, and NF-κB p65 were significantly increased partly mediated by TLR2. In addition, immunofluorescence assays revealed that the NF-κB p65 translocated into nucleus in response to V. harveyi infection. The secretion of IL-1β, IL-6, IL-12, and TNF-α were considerably reduced when the p38 MAPK and NF-κB signaling pathways were blocked, whereas blocking of AKT significantly increased the expression of IL-1β, IL-6, IL-12, and TNF-α. These findings indicate that V. harveyi infection induces inflammatory responses in murine PMs via activation of p38 MAPK and NF-κB pathways, which are partly mediated by TLR2, but are inhibited by PI3K/AKT pathways.
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Affiliation(s)
- Guili Yu
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China
| | - Hong Yu
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China
| | - Qiankun Yang
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China
| | - Jinxin Wang
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China
| | - Hui Fan
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China
| | - Gang Liu
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China
| | - Lei Wang
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China; Department of Vascular Surgery, The First People's Hospital of Lianyungang, Lianyungang, 222002, China
| | | | - Panpan Zhao
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China; Key Laboratory of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China.
| | - Honggang Zhang
- Department of Vascular Surgery, The First People's Hospital of Lianyungang, Lianyungang, 222002, China.
| | - Jingquan Dong
- Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China.
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14
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Yang XB, Zu HB, Zhao YF, Yao K. Agomelatine Prevents Amyloid Plaque Deposition, Tau Phosphorylation, and Neuroinflammation in APP/PS1 Mice. Front Aging Neurosci 2022; 13:766410. [PMID: 35153715 PMCID: PMC8828541 DOI: 10.3389/fnagi.2021.766410] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 12/20/2021] [Indexed: 01/09/2023] Open
Abstract
Agomelatine, an agonist of melatonergic MT1 and MT2 receptors and a selective 5-hydroxytryptamine 2C receptor antagonist, is widely applied in treating depression and insomnia symptoms in several neurogenerative diseases. However, the neuroprotective effect of agomelatine in Alzheimer’s disease (AD) is less known. In this study, a total of 30 mice were randomly divided into three groups, namely, wild type (WT), APP/PS1, and agomelatine (50 mg/kg). After 30 days, the Morris water maze was performed to test the cognitive ability of mice. Then, all mice were sacrificed, and the hippocampus tissues were collected for ELISA, Western blot, and immunofluorescence analysis. In this study, we found that agomelatine attenuated spatial memory deficit, amyloid-β (Aβ) deposition, tau phosphorylation, and neuroinflammation in the hippocampus of APP/PS1 mice. Further study demonstrated that agomelatine treatment upregulated the protein expression of DHCR24 and downregulated P-Akt, P-mTOR, p-p70s6k, Hes1, and Notch1 expression. In summary, our results identified that agomelatine could improve cognitive impairment and ameliorate AD-like pathology in APP/PS1 mice via activating DHCR24 signaling and inhibiting Akt/mTOR and Hes1/Notch1 signaling pathway. Agomelatine may become a promising drug candidate in the therapy of AD.
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15
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Liu Z, Yang B. CTRP6(C1q/Tumor Necrosis Factor (TNF)-related protein-6) alleviated the sevoflurane induced injury of mice central nervous system by promoting the expression of p-Akt (phosphorylated Akt). Bioengineered 2021; 12:5716-5726. [PMID: 34516328 PMCID: PMC8806630 DOI: 10.1080/21655979.2021.1967838] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Postoperative cognitive impairment and nervous system damage caused by anesthetics seriously affect patient’s postoperative recovery. Recent study has revealed that CTRP6 could alleviate apoptosis, inflammation and oxidative stress of nerve cells, thereby relieving nervous system damage induced by cerebral ischemia reperfusion. However, whether CTRP6 could relieve sevoflurane induced central nervous system injury is unclear. We stimulated C57BL/6 mice with sevoflurane and injected CTRP6 overexpression adenovirus vector. Next, H&E staining and TUNEL assays were performed to examine the effect of CTRP6 on sevoflurane induced injury of central nervous system. Finally, we isolated primary nerve cells of hippocampus. Flow cytometry and commercial kits were used for the detection of apoptosis and ROS levels of these cells. Western blotting was used for the detection of the expression level of p-Akt in central nervous tissues and primary cells. Results showed that sevoflurane induced injury and apoptosis of central nervous tissues. Overexpression of CTRP6 relieved apoptosis and injury of these tissues. CTRP6 inhibited the expression of cleaved caspase-3 and cleaved PARP in these tissues. Sevoflurane promoted apoptosis of primary cells and enhanced the expression of ROS and MDA in these cells. Overexpression of CTRP6 alleviated apoptosis and suppressed production of ROS and MDA in these cells. In addition, CTRP6 also enhanced the expression of p-Akt in primary cells. Taken together, our results suggested that CTRP6 relieved sevoflurane induced injury of central nervous tissues by promoting the expression of p-Akt. Therefore, the targeted drug of CTRP6 should be explored for the remission of these symptoms.
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Affiliation(s)
- Zhiwen Liu
- Department of Anesthesiology, The Second Hospital, University to South China Hengyang Cty, Hengyang City, Hunan Province, China
| | - Bin Yang
- Department of Anesthesiology, The Second Hospital, University to South China Hengyang Cty, Hengyang City, Hunan Province, China
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16
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Qi Z, Zhang Y, Yao K, Zhang M, Xu Y, Zhang J, Bai X, Zu H. DHCR24 Knockdown Lead to Hyperphosphorylation of Tau at Thr181, Thr231, Ser262, Ser396, and Ser422 Sites by Membrane Lipid-Raft Dependent PP2A Signaling in SH-SY5Y Cells. Neurochem Res 2021; 46:1627-1640. [PMID: 33710538 DOI: 10.1007/s11064-021-03273-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 02/05/2021] [Accepted: 02/10/2021] [Indexed: 11/27/2022]
Abstract
Accumulating data suggest that the downregulation of DHCR24 is linked to the pathological risk factors of AD, denoting a potential role of DHCR24 in AD pathogenesis. However, it remains unclear whether the downregulation of DHCR24 affects the abnormal heper-phosphorylation of tau protein, which is involved in tauopathy. In present papers, immunofluorescence and Filipin III fluorescence results showed that DHCR24 knockdown significantly lowered the level of plasma membrane cholesterol and expression level of membrane lipid-raft structural protein caveolin-1; and overexpression of DHCR24 could increase the plasma membrane cholesterol levels and facilitating caveolae structure through increase the expression of caveolin-1. PP2A is the key phosphatase involving in tau phosphorylation, which is localized in cholesterol-dependent caveola/raft lipid domains. Here, the PP2A activity was detected by western blot assay. Interestingly, the level of p-PP2Ac at Y307 (inactive) and p-GSK3β at Y216 (active) in the downstream of the PP2A signal pathway were both significantly increased in silencing DHCR24 SH-SY5Y cells, which denoted an inhibition of the PP2A and activation of GSK3β signaling. Conversely, overexpression of DHCR24 blunted the inhibition effect of PP2A and activation of GSK3β. Besides, in the SH-SY5Y cell lines we demonstrated that DHCR24 knockdown obviously induced hyperphosphorylation of tau at Thr181, Thr231, Ser262, Ser396, and Ser422 Sites. In contrast, DHCR24 overexpression protects neuronal SH-SY5Y cells against the hyperphosphorylation of tau at Thr181, Thr231, Ser262, Ser396, and Ser422 Sites. Furthermore, PP2A activator D-erythro-Sphingosine (DES) also obviously inhibited the hyperphosphorylation of tau induced by DHCR24 knockdown. Collectively, our findings firstly confirmed that DHCR24 knockdown obviously induced abnormal hyperphosphorylation of tau by a novel lipid raft-dependent PP2A signaling. We propose that DHCR24 downregulation led to altered cholesterol synthesis as a potential mechanism in the progression of tau hyperphosphorylation involving in AD and other tauopathies.
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Affiliation(s)
- Zihan Qi
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China
| | - Ying Zhang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China
| | - Kai Yao
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China
| | - Mengqi Zhang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China
| | - Yixuan Xu
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China
| | - Jianfeng Zhang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China
| | - Xiaojing Bai
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China.
| | - Hengbing Zu
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, 201508, China.
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