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Aguilera-Lizarraga J, Ritoux A, Bulmer DC, Smith ESJ. Intestinal barrier function in the naked mole-rat: an emergent model for gastrointestinal insights. Am J Physiol Gastrointest Liver Physiol 2024; 327:G188-G201. [PMID: 38915279 DOI: 10.1152/ajpgi.00080.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 06/10/2024] [Accepted: 06/19/2024] [Indexed: 06/26/2024]
Abstract
The intestinal barrier plays a crucial role in homeostasis by both facilitating the absorption of nutrients and fluids and providing a tight shield to prevent the invasion by either pathogen or commensal microorganisms. Intestinal barrier malfunction is associated with systemic inflammation, oxidative stress, and decreased insulin sensitivity, which may lead to the dysregulation of other tissues. Therefore, a deeper understanding of physiological aspects related to an enhanced barrier function is of significant scientific and clinical relevance. The naked mole-rat has many unusual biological features, including attenuated colonic neuron sensitivity to acid and bradykinin and resistance to chemical-induced intestinal damage. However, insight into their intestinal barrier physiology is scarce. Here, we observed notable macroscopic and microscopic differences in intestinal tissue structure between naked mole-rats and mice. Moreover, naked mole-rats showed increased number of larger goblet cells and elevated mucus content. In measuring gut permeability, naked mole-rats showed reduced permeability compared with mice, measured as transepithelial electrical resistance, especially in ileum. Furthermore, intestinal ion secretion induced by serotonin, bradykinin, histamine, and capsaicin was significantly reduced in naked mole-rats compared with mice, despite the expression of receptors for all these agonists. In addition, naked mole-rats exhibited reduced prosecretory responses to the nonselective adenylate cyclase activator forskolin. Collectively, these findings indicate that naked mole-rats possess a robust and hard-to-penetrate gastrointestinal barrier that is resistant to environmental and endogenous irritants. Naked mole-rats may therefore provide valuable insights into the physiology of the intestinal barrier and set the stage for the development of innovative and effective therapies.NEW & NOTEWORTHY This is the first study to characterize the intestinal function of naked mole-rats. We found that these animals show a robust gut tissue structure, displaying thicker intestinal layers, longer villi, and larger crypts. Naked mole-rats showed more and larger goblet cells, with increased mucus content. Intestinal permeability, especially in the ileum, was substantially lower than that of mice. Finally, naked mole-rats showed reduced intestinal anion secretion in response to serotonin, bradykinin, histamine, capsaicin, and forskolin.
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Affiliation(s)
| | - Anne Ritoux
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - David C Bulmer
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
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Wang S, Zhang K, Huang Q, Meng F, Deng S. TLR4 signalling in ischemia/reperfusion injury: a promising target for linking inflammation, oxidative stress and programmed cell death to improve organ transplantation outcomes. Front Immunol 2024; 15:1447060. [PMID: 39091500 PMCID: PMC11291251 DOI: 10.3389/fimmu.2024.1447060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 07/05/2024] [Indexed: 08/04/2024] Open
Abstract
Transplantations represent the principal therapeutic interventions for terminal organ failure, a procedure that has salvaged myriad lives annually. Ischemia/reperfusion injury (IRI) is frequently correlated with an unfavourable prognosis and is relevant for early graft dysfunction and graft survival. IRI constitutes a complex pathological state influenced by a series of factors such as oxidative stress, metabolic stress, leukocytic infiltration, programmed cell death pathways, and inflammatory immune responses. Reducing ischemia/reperfusion injury is one of the main directions of transplantation research. Toll-like receptors (TLRs) are important pattern-recognition receptors expressed on various organs that orchestrate the immune responses upon recognising PAMPs and DAMPs. Targeting the TLR4 signalling has recently been suggested as a promising approach for alleviating IRI by affecting inflammation, oxidative stress and programmed cell death (PCD). In this minireview, we summarise the role of TLR4 signalling in regulating inflammation, oxidative stress and PCD in organ transplantation and discuss their interactions during IRI. A detailed understanding of the multiple functions of TLR4 in IRI provides novel insights into developing therapies to improve organ transplantation outcomes.
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Affiliation(s)
- Sutian Wang
- State Key Laboratory of Swine and Poultry Breeding Industry, Guangdong Key Laboratory of Animal Breeding and Nutrition, Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Kunli Zhang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China
| | - Qiuyan Huang
- State Key Laboratory of Swine and Poultry Breeding Industry, Guangdong Key Laboratory of Animal Breeding and Nutrition, Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Fanming Meng
- State Key Laboratory of Swine and Poultry Breeding Industry, Guangdong Key Laboratory of Animal Breeding and Nutrition, Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Shoulong Deng
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China
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He Y, Zhao J, Dong H, Zhang X, Duan Y, Ma Y, Yu M, Fei J, Huang F. TLR2 deficiency is beneficial at the late phase in MPTP-induced Parkinson' disease mice. Life Sci 2023; 333:122171. [PMID: 37827233 DOI: 10.1016/j.lfs.2023.122171] [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: 01/30/2023] [Revised: 10/07/2023] [Accepted: 10/09/2023] [Indexed: 10/14/2023]
Abstract
AIMS Parkinson's disease (PD) is a progressive neurodegenerative disorder. The etiology of PD is still elusive but neuroinflammation is proved to be an important contributor. Toll-like receptor 2 (TLR2) involves in the release of several inflammatory cytokines. Whether TLR2 serves as a mediator contributing to the damage of DA system in PD remain unclear. MAIN METHODS Tlr2 knockout (Tlr2-/-) and wild-type (WT) mice were treated with a subacute regimen of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). At 3, 7 and 14 days after MPTP injection, the behavioral performance, including the Pole test, the Rotarod test, the Rearing test and the Wire hang test was evaluated. Moreover, the PD-like phenotypes, including dopaminergic degeneration, the activation of glial cells and the α-Syn expression were systematically analyzed in the nigrostriatal pathway. Finally, the composition of gut microbiota in the MPTP-treated groups were assessed. KEY FINDINGS TLR2 deficiency had no obvious impact on the dopaminergic injury at 3 and 7 days following MPTP administration. On the contrary, at 14 days post injection, TLR2 deficiency not only significantly attenuated motor deficits in the Pole test and the Rotarod test, and the nigrostriatal dopaminergic degeneration, but also mitigated α-Syn abnormality, astrocyte activation and neuroinflammation through the suppressed TLR2/MyD88/TRAF6/NF-κB signaling pathways. Additionally, the alteration of gut microbiota was also detected in the mutant mice. SIGNIFICANCE These findings highlight the neuroprotective effect of TLR2-pathways at the late phase in the MPTP-induced PD mouse model.
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Affiliation(s)
- Yongtao He
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
| | - Jiayin Zhao
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
| | - Hongtian Dong
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
| | - Xiaoshuang Zhang
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
| | - Yufei Duan
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
| | - Yuanyuan Ma
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
| | - Mei Yu
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China.
| | - Jian Fei
- School of Life Science and Technology, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Engineering Research Center for Model Organisms, Shanghai Model Organisms Center, INC., Shanghai 201203, China.
| | - Fang Huang
- Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China.
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Chu C, Wang X, Yang C, Chen F, Shi L, Xu W, Wang K, Liu B, Wang C, Sun D, Ding W. Neutrophil extracellular traps drive intestinal microvascular endothelial ferroptosis by impairing Fundc1-dependent mitophagy. Redox Biol 2023; 67:102906. [PMID: 37812880 PMCID: PMC10579540 DOI: 10.1016/j.redox.2023.102906] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/19/2023] [Accepted: 09/25/2023] [Indexed: 10/11/2023] Open
Abstract
Microvascular endothelial damage caused by intestinal ischemia‒reperfusion (II/R) is a primary catalyst for microcirculation dysfunction and enterogenous infection. Previous studies have mainly focused on how neutrophil extracellular traps (NETs) and ferroptosis cause intestinal epithelial injury, and little attention has been given to how NETs, mainly from circulatory neutrophils, affect intestinal endothelial cells during II/R. This study aimed to unravel the mechanisms through which NETs cause intestinal microvascular dysfunction. We first detected heightened local NET infiltration around the intestinal microvasculature, accompanied by increased endothelial cell ferroptosis, resulting in microcirculation dysfunction in both human and animal II/R models. However, the administration of the ferroptosis inhibitor ferrostatin-1 or the inhibition of NETs via neutrophil-specific peptidylarginine deiminase 4 (Pad4) deficiency led to positive outcomes, with reduced intestinal endothelial ferroptosis and microvascular function recovery. Moreover, RNA-seq analysis revealed a significant enrichment of mitophagy- and ferroptosis-related signaling pathways in HUVECs incubated with NETs. Mechanistically, elevated NET formation induced Fundc1 phosphorylation at Tyr18 in intestinal endothelial cells, which led to mitophagy inhibition, mitochondrial quality control imbalance, and excessive mitochondrial ROS generation and lipid peroxidation, resulting in endothelial ferroptosis and microvascular dysfunction. Nevertheless, using the mitophagy activator urolithin A or AAV-Fundc1 transfection could reverse this process and ameliorate microvascular damage. We first demonstrate that increased NETosis could result in intestinal microcirculatory dysfunction and conclude that suppressed NET formation can mitigate intestinal endothelial ferroptosis by improving Fundc1-dependent mitophagy. Targeting NETs could be a promising approach for treating II/R-induced intestinal microcirculatory dysfunction.
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Affiliation(s)
- Chengnan Chu
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China
| | - Xinyu Wang
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China
| | - Chao Yang
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China
| | - Fang Chen
- School of Medicine, Southeast University, Nanjing, 210002, Jiangsu Province, China
| | - Lin Shi
- Institute of Chemicobiology and Functional Materials, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, 200 Xiao Ling Wei Street, Nanjing, 210094, Jiangsu Province, China
| | - Weiqi Xu
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China
| | - Kai Wang
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China
| | - Baochen Liu
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China
| | - Chenyang Wang
- Key Laboratory of Intestinal Injury, Research Institute of General Surgery, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, Jiangsu, PR China
| | - Dongping Sun
- Institute of Chemicobiology and Functional Materials, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, 200 Xiao Ling Wei Street, Nanjing, 210094, Jiangsu Province, China
| | - Weiwei Ding
- Division of Trauma and Acute Care Surgery, Department of Surgery, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, China.
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Protective Effect of Oxygen and Isoflurane in Rodent Model of Intestinal Ischemia-Reperfusion Injury. Int J Mol Sci 2023; 24:ijms24032587. [PMID: 36768910 PMCID: PMC9917127 DOI: 10.3390/ijms24032587] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 01/22/2023] [Accepted: 01/27/2023] [Indexed: 01/31/2023] Open
Abstract
Animal research in intestinal ischemia-reperfusion injury (IRI) is mainly performed in rodent models. Previously, intraperitoneal (I.P.) injections with ketamine-xylazine mixtures were used. Nowadays, volatile anesthetics (isoflurane) are more common. However, the impact of the anesthetic method on intestinal IRI has not been investigated. We aim to analyze the different anesthetic methods and their influence on the extent of intestinal IRI in a rat model. Male Sprague-Dawley rats were used to investigate the effect of I.P. anesthesia on 60 min of intestinal ischemia and 60 min of reperfusion in comparison to hyperoxygenation (100% O2) and volatile isoflurane anesthesia. In comparison to I.P. anesthesia with room air (21% O2), supplying 100% O2 improved 7-day survival by cardiovascular stabilization, reducing lactic acidosis and preventing vascular leakage. However, this had no effect on the intestinal epithelial damage, permeability, and inflammatory response observed after intestinal IRI. In contrast to I.P. + 100% O2, isoflurane anesthesia reduced intestinal IRI by preventing ongoing low-flow reperfusion hypotension, limiting intestinal epithelial damage and permeability, and by having anti-inflammatory effects. When translating the aforementioned results of this study to clinical situations, such as intestinal ischemia or transplantation, the potential protective effects of hyperoxygenation and volatile anesthetics require further research.
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Karousou E, Parnigoni A, Moretto P, Passi A, Viola M, Vigetti D. Hyaluronan in the Cancer Cells Microenvironment. Cancers (Basel) 2023; 15:cancers15030798. [PMID: 36765756 PMCID: PMC9913668 DOI: 10.3390/cancers15030798] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/03/2023] Open
Abstract
The presence of the glycosaminoglycan hyaluronan in the extracellular matrix of tissues is the result of the cooperative synthesis of several resident cells, that is, macrophages and tumor and stromal cells. Any change in hyaluronan concentration or dimension leads to a modification in stiffness and cellular response through receptors on the plasma membrane. Hyaluronan has an effect on all cancer cell behaviors, such as evasion of apoptosis, limitless replicative potential, sustained angiogenesis, and metastasis. It is noteworthy that hyaluronan metabolism can be dramatically altered by growth factors and matrikines during inflammation, as well as by the metabolic homeostasis of cells. The regulation of HA deposition and its dimensions are pivotal for tumor progression and cancer patient prognosis. Nevertheless, because of all the factors involved, modulating hyaluronan metabolism could be tough. Several commercial drugs have already been described as potential or effective modulators; however, deeper investigations are needed to study their possible side effects. Moreover, other matrix molecules could be identified and targeted as upstream regulators of synthetic or degrading enzymes. Finally, co-cultures of cancer, fibroblasts, and immune cells could reveal potential new targets among secreted factors.
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