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Wang J, Liu S, Xie Y, Xu C. Association analysis of gut microbiota-metabolites-neuroendocrine changes in male rats acute exposure to simulated altitude of 5500 m. Sci Rep 2023; 13:9225. [PMID: 37286697 DOI: 10.1038/s41598-023-35573-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 05/20/2023] [Indexed: 06/09/2023] Open
Abstract
Hyperactivation of hypothalamic-pituitary-adrenal (HPA) axis and hypothalamic-pituitary-thyroid (HPT) axis were found in acute high altitude challenge, but the role of gut microbiota and metabolites is unknown. We utilized adult male Sprague-Dawley rats at a simulated altitude of 5500 m for 3 days in a hypobaric-hypoxic chamber. ELISA and metabolomic analyses of serum and 16S rRNA and metabolomic analyses of fecal samples were then performed. Compared with the normoxic group, serum corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), corticosterone (CORT), and thyroxine (tT4) were increased in the hypoxia group, whereas thyrotropin-releasing hormone (TRH) was decreased. Bacteroides, Lactobacillus, Parabacteroides, Butyricimonas, SMB53, Akkermansia, Phascolarctobacterium, and Aerococcus were enriched in hypoxia group, whereas [Prevotella], Prevotella, Kaistobacter, Salinibacterium, and Vogesella were enriched in normoxic group. Metabolomic analysis indicated that acute hypoxia significantly affected fecal and serum lipid metabolism. In addition, we found five fecal metabolites may mediate the cross-talk between TRH, tT4, and CORT with [Prevotella], Kaistobacter, Parabacteroides, and Aerococcus, and 6 serum metabolites may mediate the effect of TRH and tT4 on [Prevotella] and Kaistobacter by causal mediation analysis. In conclusion, this study provides new evidence that key metabolites mediate the cross-talk between gut microbiota with HPA and HPT axis under acute hypobaric hypoxia challenge.
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Affiliation(s)
- Jianan Wang
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Shiying Liu
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Yalei Xie
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Chengli Xu
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
- Center of Environmental and Health Sciences, Chinese Academy of Medical Sciences, Beijing, 100005, China.
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Wang TY, Xia FY, Gong JW, Xu XK, Lv MC, Chatoo M, Shamsi BH, Zhang MC, Liu QR, Liu TX, Zhang DD, Lu XJ, Zhao Y, Du JZ, Chen XQ. CRHR1 mediates the transcriptional expression of pituitary hormones and their receptors under hypoxia. Front Endocrinol (Lausanne) 2022; 13:893238. [PMID: 36147561 PMCID: PMC9487150 DOI: 10.3389/fendo.2022.893238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 08/03/2022] [Indexed: 11/13/2022] Open
Abstract
Hypothalamus-pituitary-adrenal (HPA) axis plays critical roles in stress responses under challenging conditions such as hypoxia, via regulating gene expression and integrating activities of hypothalamus-pituitary-targets cells. However, the transcriptional regulatory mechanisms and signaling pathways of hypoxic stress in the pituitary remain to be defined. Here, we report that hypoxia induced dynamic changes in the transcription factors, hormones, and their receptors in the adult rat pituitary. Hypoxia-inducible factors (HIFs), oxidative phosphorylation, and cAMP signaling pathways were all differentially enriched in genes induced by hypoxic stress. In the pituitary gene network, hypoxia activated c-Fos and HIFs with specific pituitary transcription factors (Prop1), targeting the promoters of hormones and their receptors. HIF and its related signaling pathways can be a promising biomarker during acute or constant hypoxia. Hypoxia stimulated the transcription of marker genes for microglia, chemokines, and cytokine receptors of the inflammatory response. Corticotropin-releasing hormone receptor 1 (CRHR1) mediated the transcription of Pomc, Sstr2, and Hif2a, and regulated the function of HPA axis. Together with HIF, c-Fos initiated and modulated dynamic changes in the transcription of hormones and their receptors. The receptors were also implicated in the regulation of functions of target cells in the pituitary network under hypoxic stress. CRHR1 played an integrative role in the hypothalamus-pituitary-target axes. This study provides new evidence for CRHR1 involved changes of hormones, receptors, signaling molecules and pathways in the pituitary induced by hypoxia.
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Affiliation(s)
- Tong Ying Wang
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
- Department of Research and Development, Jiuyuan Gene Engineering, Hangzhou, China
| | - Fang Yuan Xia
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Jing Wen Gong
- Department of Pathology, and Department of Medical Oncology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiao Kang Xu
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Min Chao Lv
- Department of Orthopedics, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China
| | - Mahanand Chatoo
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Bilal Haider Shamsi
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Meng Chen Zhang
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Qian Ru Liu
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Tian Xing Liu
- Department of Cell and System Biology, University of Toronto, St. George, NB, Canada
| | - Dan Dan Zhang
- Department of Pathology, and Department of Medical Oncology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xin Jiang Lu
- Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Yang Zhao
- Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Ji Zeng Du
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Xue Qun Chen
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
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3
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Fang J, Chang X. Celastrol inhibits the proliferation and angiogenesis of high glucose-induced human retinal endothelial cells. Biomed Eng Online 2021; 20:65. [PMID: 34193168 PMCID: PMC8244207 DOI: 10.1186/s12938-021-00904-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 06/20/2021] [Indexed: 11/13/2022] Open
Abstract
Background Diabetic retinopathy (DR) is one of the most common microvascular complications of diabetes. Celastrol plays a certain role in the improvement of various diabetes complications. Therefore, this study aimed to explore whether celastrol inhibited the proliferation and angiogenesis of high glucose (HG)-induced human retinal endothelial cells (hRECs) by down-regulating the HIF1/VEGF signaling pathway. Methods The viability and proliferation of hRECs treated with glucose, celastrol or dimethyloxallyl glycine (DMOG) were analyzed by MTT assay. The invasion and tube formation ability of hRECs treated with glucose, celastrol or DMOG were in turn detected by transwell assay and tube formation assay. The expression of HIF1α and VEGF in hRECs after indicated treatment was analyzed by Western blot analysis and RT-qPCR analysis and ICAM-1 expression in hRECs after indicated treatment was detected by immunofluorescence assay Results HG induction promoted the proliferation, invasion and tube formation ability and increased the expression of HIF-1α and VEGF of hRECs, which were gradually suppressed by celastrol changing from 0.5 to 2.0 μM. DMOG was regarded as a HIF1α agonist, which attenuated the effect of celastrol on HG-induced hRECs. Conclusion Celastrol inhibited the proliferation and angiogenesis of HG-induced hRECs by down-regulating the HIF1α/VEGF signaling pathway.
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Affiliation(s)
- Jian Fang
- Department of Ophthalmology, Xinchang County People's Hospital, Shaoxing, 312500, Zhejiang, China
| | - Xiaoke Chang
- Hankou Aier Eye Hospital, No.328, Machang Road, Jianghan District, Wuhan, 430000, Hubei, China.
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Kietzmann T, Mäkelä VH. The hypoxia response and nutritional peptides. Peptides 2021; 138:170507. [PMID: 33577839 DOI: 10.1016/j.peptides.2021.170507] [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: 12/15/2020] [Revised: 01/29/2021] [Accepted: 02/03/2021] [Indexed: 10/22/2022]
Abstract
Hypoxia controls metabolism at several levels, e.g., via mitochondrial ATP production, glucose uptake and glycolysis. Hence it is likely that hypoxia also affects the action and/or production of many peptide hormones linked to food intake and appetite control. Many of those are produced in the gastrointestinal tract, endocrine pancreas, adipose tissue, and selective areas in the brain which modulate and concert their actions. However, the complexity of the hypoxia response and the links to peptides/hormones involved in food intake and appetite control in the different organs are not well known. This review summarizes the role of the hypoxia response and its effects on major peptides linked to appetite regulation, nutrition and metabolism.
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Affiliation(s)
- Thomas Kietzmann
- University of Oulu, Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, Oulu, Finland.
| | - Ville H Mäkelä
- University of Oulu, Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, Oulu, Finland
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5
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Ye S, Zhou HB, Chen Y, Li KQ, Jiang SS, Hao K. Crizotinib changes the metabolic pattern and inhibits ATP production in A549 non-small cell lung cancer cells. Oncol Lett 2020; 21:61. [PMID: 33281972 PMCID: PMC7709560 DOI: 10.3892/ol.2020.12323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 10/20/2020] [Indexed: 01/25/2023] Open
Abstract
Crizotinib, an inhibitor of the hepatocyte growth factor receptor oncogene, has been studied extensively regarding its antitumor and clinically beneficial effects in non-small cell lung cancer (NSCLC). However, crizotinib's effects on cancer cell energy metabolism, which is linked with tumor proliferation and migration, in NSCLC are unclear. Therefore, the present study focused on crizotinib's effect on NSCLC glucose metabolism. Crizotinib's effects on glucose metabolism, proliferation, migration and apoptosis in A549 cells were explored. Several other inhibitors, including 2-DG, rotenone and MG132, were used to define the mechanism of action in further detail. Data showed that crizotinib treatment reduced A549 cell viability, increased glucose consumption and lactate production, while decreased mitochondrial transmembrane potential (Δψm) and ATP production. Crizotinib treatment, combined with rotenone and MG132 treatment, further inhibited ATP production and Δψm and increased reactive oxygen species content. However, crizotinib did not suppress cell proliferation, migration, ATP production, Δψm or mitochondrial-related apoptosis signals further following 2-DG-mediated inhibition of glycolysis. These results indicated that crizotinib induced low mitochondrial function and compensatory high anaerobic metabolism, but failed to maintain sufficient ATP levels. The alternation of metabolic pattern and insufficient ATP supply may serve important roles in the metabolic antitumor mechanism of crizotinib in A549 cells.
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Affiliation(s)
- Sa Ye
- Department of Nutrition, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Hong-Bin Zhou
- Department of Respiratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Ying Chen
- Department of Nutrition, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Kai-Qiang Li
- Research Center of Blood Transfusion Medicine, Ministry of Education Key Laboratory of Laboratory Medicine, Department of Blood Transfusion, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Shan-Shan Jiang
- Research Center of Blood Transfusion Medicine, Ministry of Education Key Laboratory of Laboratory Medicine, Department of Blood Transfusion, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Ke Hao
- Research Center of Blood Transfusion Medicine, Ministry of Education Key Laboratory of Laboratory Medicine, Department of Blood Transfusion, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
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Khan S, Lu X, Huang Q, Tang J, Weng J, Yang Z, Lv M, Xu X, Xia F, Zhang M, Li Y, Liu S, Leng G, Spitzer N, Du J, Chen X. IGFBP2 Plays an Essential Role in Cognitive Development during Early Life. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1901152. [PMID: 31832311 PMCID: PMC6891907 DOI: 10.1002/advs.201901152] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/02/2019] [Indexed: 06/10/2023]
Abstract
Identifying the mechanisms underlying cognitive development in early life is a critical objective. The expression of insulin-like growth factor binding protein 2 (IGFBP2) in the hippocampus increases during neonatal development and is associated with learning and memory, but a causal connection has not been established. Here, it is reported that neurons and astrocytes expressing IGFBP2 are distributed throughout the hippocampus. IGFBP2 enhances excitatory inputs onto CA1 pyramidal neurons, facilitating intrinsic excitability and spike transmission, and regulates plasticity at excitatory synapses in a cell-type specific manner. It facilitates long-term potentiation (LTP) by enhancing N-methyl-d-aspartate (NMDA) receptor-dependent excitatory postsynaptic current (EPSC), and enhances neurite proliferation and elongation. Knockout of igfbp2 reduces the numbers of pyramidal cells and interneurons, impairs LTP and cognitive performance, and reduces tonic excitation of pyramidal neurons that are all rescued by IGFBP2. The results provide insight into the requirement for IGFBP2 in cognition in early life.
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Affiliation(s)
- Shumsuzzaman Khan
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
- Present address:
Case Western Reserve UniversityClevelandOhioUSA
| | - Xinjiang Lu
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Qingyao Huang
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Jiawei Tang
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Jian Weng
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Zhi Yang
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Minchao Lv
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Xiaokang Xu
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Fangyuan Xia
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Mengchen Zhang
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Yi Li
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Shuangshuang Liu
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Gareth Leng
- Experimental PhysiologyUniversity of EdinburghEdinburghEH8 9XDUK
| | | | - Jizeng Du
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
| | - Xuequn Chen
- Institute of NeuroscienceDepartment of Neurobiology, and Department of Neurology of Second Affiliated HospitalNHC and CAMS Key Laboratory of Medical NeurobiologyKey Laboratory of Medical Neurobiology of Zhejiang ProvinceZhejiang University School of MedicineHangzhou310058China
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Serebrovska TV, Portnychenko AG, Portnichenko VI, Xi L, Egorov E, Antoniuk-Shcheglova I, Naskalova S, Shatylo VB. Effects of intermittent hypoxia training on leukocyte pyruvate dehydrogenase kinase 1 (PDK-1) mRNA expression and blood insulin level in prediabetes patients. Eur J Appl Physiol 2019; 119:813-823. [PMID: 30701312 DOI: 10.1007/s00421-019-04072-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 01/04/2019] [Indexed: 02/08/2023]
Abstract
PURPOSE Intermittent hypoxia training/treatment (IHT) is an emerging therapeutic approach to alleviate chronic diseases, such as diabetes. The present study investigated the effects of IHT on blood leucocyte pyruvate dehydrogenase kinase 1 (PDK-1) mRNA expression and its relationship with the changes in blood insulin level. METHODS Seven adult healthy volunteers and 11 prediabetic patients participated in this study. A 3-week course of IHT consisted of a 40-min session of 4 cycles of 5-min 12% O2 and 5-min room air breathing per day, 3 sessions per week for 3 weeks (i.e., total 9 sessions of IHT). Plasma insulin levels and leukocyte PDK-1 mRNA expression were determined at various time points either under fasting condition or following oral glucose tolerance test (OGTT). Correlation between the IHT-induced changes in PDK-1 mRNA and insulin or glucose levels in the same serological samples was analyzed. RESULTS At pre-IHT baseline, PDK-1 mRNA expression was two times higher in prediabetes than control subjects. IHT resulted in significant augmentation in PDK-1 mRNA expression (> twofold) in prediabetes at the end of 3-week IHT and remained elevated 1 month after IHT, which was correlated with a significantly reduced insulin release and lower blood glucose after glucose loading with OGTT. CONCLUSION IHT can trigger beneficial effects in normalizing blood insulin levels in prediabetic patients under oral glucose load, which were closely correlated with an enhanced mRNA expression of PDK-1 in leukocytes. Further clinical trials are warranted to validate the utility of IHT as a non-invasive complementary therapy against diabetes-associated pathologies.
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Affiliation(s)
| | - Alla G Portnychenko
- Bogomoletz Institute of Physiology, Kiev, 01024, Ukraine
- ICAMER, National Academy of Sciences of Ukraine, Kiev, 03680, Ukraine
| | - Vladimir I Portnichenko
- Bogomoletz Institute of Physiology, Kiev, 01024, Ukraine
- ICAMER, National Academy of Sciences of Ukraine, Kiev, 03680, Ukraine
| | - Lei Xi
- Pauley Heart Center, Department of Internal Medicine, Virginia Commonwealth University, 1101 East Marshall Street, Room 7-020C, Richmond, VA, 23298, USA.
- School of Sports Medicine and Health, Chengdu Sport University, Chengdu, 610041, China.
| | - Egor Egorov
- CELLGYM Technologies GmbH, 10623, Berlin, Germany
| | | | | | - Valeriy B Shatylo
- D.F. Chebotarev State Institute of Gerontology, Kiev, 04114, Ukraine
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Joyce K, Lucas S, Imray C, Balanos G, Wright AD. Advances in the available non-biological pharmacotherapy prevention and treatment of acute mountain sickness and high altitude cerebral and pulmonary oedema. Expert Opin Pharmacother 2018; 19:1891-1902. [DOI: 10.1080/14656566.2018.1528228] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- K.E. Joyce
- School of Sport, Exercise, & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - S.J.E. Lucas
- School of Sport, Exercise, & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - C.H.E. Imray
- Department of Vascular Surgery, University Hospitals of Coventry and Warwickshire; Warwick Medical School, Coventry, UK
| | - G.M Balanos
- School of Sport, Exercise, & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - A. D. Wright
- Department of Medicine, University of Birmingham, Edgbaston, UK
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9
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Abu Eid S, Hackl MT, Kaplanian M, Winter MP, Kaltenecker D, Moriggl R, Luger A, Scherer T, Fürnsinn C. Life Under Hypoxia Lowers Blood Glucose Independently of Effects on Appetite and Body Weight in Mice. Front Endocrinol (Lausanne) 2018; 9:490. [PMID: 30210452 PMCID: PMC6121030 DOI: 10.3389/fendo.2018.00490] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 08/06/2018] [Indexed: 11/13/2022] Open
Abstract
Blood glucose and the prevalence of diabetes are lower in mountain than lowland dwellers, which could among other factors be due to reduced oxygen availability. To investigate metabolic adaptations to life under hypoxia, male mice on high fat diet (HFD) were continuously maintained at 10% O2. At variance to preceding studies, the protocol was designed to dissect direct metabolic effects from such mediated indirectly via hypoxia-induced reductions in appetite and weight gain. This was achieved by two separate control groups on normal air, one with free access to HFD, and one fed restrictedly in order to obtain a weight curve matching that of hypoxia-exposed mice. Comparable body weight in restrictedly fed and hypoxic mice was achieved by similar reductions in calorie intake (-22%) and was associated with parallel effects on body composition as well as on circulating insulin, leptin, FGF-21, and adiponectin. Whereas the effects of hypoxia on the above parameters could thus be attributed entirely to blunted weight gain, hypoxia improved glucose homeostasis in part independently of body weight (fasted blood glucose, mmol/l: freely fed control, 10.2 ± 0.7; weight-matched control, 8.0 ± 0.3; hypoxia, 6.8 ± 0.2; p < 0.007 each; AUC in the glucose tolerance test, mol/l*min: freely fed control, 2.54 ± 0.15; weight-matched control, 1.86 ± 0.08; hypoxia, 1.67 ± 0.05; p < 0.05 each). Although counterintuitive to lowering of glycemia, insulin sensitivity appeared to be impaired in animals adapted to hypoxia: In the insulin tolerance test, hypoxia-treated mice started off with lower glycaemia than their weight-matched controls (initial blood glucose, mmol/l: freely fed control, 11.5 ± 0.7; weight-matched control, 9.4 ± 0.3; hypoxia, 8.1 ± 0.2; p < 0.02 each), but showed a weaker response to insulin (final blood glucose, mmol/l: freely fed control, 7.0 ± 0.3; weight-matched control, 4.5 ± 0.2; hypoxia, 5.5 ± 0.3; p < 0.01 each). Furthermore, hypoxia weight-independently reduced hepatic steatosis as normalized to total body fat, suggesting a shift in the relative distribution of triglycerides from liver to fat (mg/g liver triglycerides per g total fat mass: freely fed control, 10.3 ± 0.6; weight-matched control, 5.6 ± 0.3; hypoxia, 4.0 ± 0.2; p < 0.0004 each). The results show that exposure of HFD-fed mice to continuous hypoxia leads to a unique metabolic phenotype characterized by improved glucose homeostasis along with evidence for impaired rather than enhanced insulin sensitivity.
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Affiliation(s)
- Sameer Abu Eid
- Division of Endocrinology & Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Martina T. Hackl
- Division of Endocrinology & Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Mairam Kaplanian
- Division of Endocrinology & Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Max-Paul Winter
- Division of Cardiology, Department of Medicine II, Medical University of Vienna, Vienna, Austria
| | - Doris Kaltenecker
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
| | - Richard Moriggl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
- Medical University of Vienna, Vienna, Austria
| | - Anton Luger
- Division of Endocrinology & Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Thomas Scherer
- Division of Endocrinology & Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Clemens Fürnsinn
- Division of Endocrinology & Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
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10
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Abd Allah ESH, Mahmoud AM. Melatonin attenuates chronic immobilization stress-induced muscle atrophy in rats: Influence on lactate-to-pyruvate ratios and Na +/K + ATPase activity. PATHOPHYSIOLOGY 2018; 25:353-357. [PMID: 29921483 DOI: 10.1016/j.pathophys.2018.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 06/13/2018] [Accepted: 06/14/2018] [Indexed: 01/28/2023] Open
Abstract
This study assessed the protective effect of melatonin against muscle atrophy provoked by chronic immobilization stress (CIS). CIS was induced in rats by limiting their trunk movement for 90 min daily for 6 weeks. Rats subjected to the CIS procedure demonstrated a substantial decrease in body weight, an increase in serum corticosterone, muscle atrophy, and an increase in atrogin-1 mRNA levels. An increase in the serum lactate-to-pyruvate ratio and the oxidative stress accompanied by a reduction of Na+/K+ ATPase activity could be responsible for these changes. Melatonin efficiently attenuated CIS-induced deleterious effects on the muscle by reducing corticosterone levels, the lactate-to-pyruvate ratio, and oxidative stress, thereby improving Na+/K+ ATPase activity and muscle condition. We conclude that melatonin can contribute to the prevention of CIS-induced muscle atrophy via its anti-stress, anti-oxidant properties and its effect on Na+/K+ ATPase activity.
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Affiliation(s)
- Eman S H Abd Allah
- Medical Physiology Department, Faculty of Medicine, Assiut University, Assiut, Egypt.
| | - Ahmed M Mahmoud
- Medical Physiology Department, Faculty of Medicine, Sohag University, Sohag, Egypt
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Shi YJ, Ma ZQ, Tang JW, Zhao Y, Wang X, Liu Q, Wang PP, John C, Chen XQ, Du JZ. The integration of multiple signaling pathways provides for bidirectional control of CRHR1 gene transcription in rat pituitary cell during hypoxia. Mol Cell Endocrinol 2017; 454:12-22. [PMID: 28572045 DOI: 10.1016/j.mce.2017.05.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 05/06/2017] [Accepted: 05/26/2017] [Indexed: 10/19/2022]
Abstract
Hypoxia upregulates hypothalamic corticotrophin releasing hormone (CRH) and its receptor type-1 (CRHR1) expression and activates the HPA axis and induces hypoxic sickness and behavioral change. The transcriptional mechanism by which hypoxia differently regulates CRHR1 expression remains unclear. Here we report hypoxia time-dependently induced biphasic expression of CRHR1mRNA in rat pituitary during different physiological status. Short exposure of gestational dams to hypoxia reduced CRHR1mRNA in the pituitary of P1-P14 male rat offspring. A short- and prolonged-hypoxia evoked biphasic response of CRHR1mRNA characterized initially by decreases and subsequently by persistent increases, mediated by a rapid negative feedback via CRHR1 signaling and positive transcriptional control via NF-κB, respectively. Further analysis of CRHR1 promoter in cultured primary anterior pituitary and AtT20 cells showed that c-Jun/AP-1 delivered negative while HIF-1α and NF-κB delivered positive control of transcription at CRHR1 promoter. The negative and positive inputs are integrated by hypoxic initiation and duration in CRHR1 transcription.
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Affiliation(s)
- Yan Jun Shi
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Zhi Qiang Ma
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Jia Wei Tang
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Yang Zhao
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Xi Wang
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Qing Liu
- WHO Collaborating Center for Research in Human Reproduction, Division of Science and Technology & Foreign Affairs, National Research Institute for Family Planning, Beijing, 100081, China
| | - Ping Ping Wang
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Coote John
- School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, B15 2TT, UK
| | - Xue Qun Chen
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Medical Neurobiology, The Ministry of Health, China; Zhejiang Province Key Laboratory for Neurobiology, Hangzhou, 310058, China.
| | - Ji Zeng Du
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Medical Neurobiology, The Ministry of Health, China; Zhejiang Province Key Laboratory for Neurobiology, Hangzhou, 310058, China.
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12
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Bazo‐Alvarez JC, Quispe R, Pillay TD, Bernabé‐Ortiz A, Smeeth L, Checkley W, Gilman RH, Málaga G, Miranda JJ. Glycated haemoglobin (HbA 1c ) and fasting plasma glucose relationships in sea-level and high-altitude settings. Diabet Med 2017; 34:804-812. [PMID: 28196274 PMCID: PMC5432378 DOI: 10.1111/dme.13335] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/09/2017] [Indexed: 12/28/2022]
Abstract
AIM Higher haemoglobin levels and differences in glucose metabolism have been reported among high-altitude residents, which may influence the diagnostic performance of HbA1c . This study explores the relationship between HbA1c and fasting plasma glucose (FPG) in populations living at sea level and at an altitude of > 3000 m. METHODS Data from 3613 Peruvian adults without a known diagnosis of diabetes from sea-level and high-altitude settings were evaluated. Linear, quadratic and cubic regression models were performed adjusting for potential confounders. Receiver operating characteristic (ROC) curves were constructed and concordance between HbA1c and FPG was assessed using a Kappa index. RESULTS At sea level and high altitude, means were 13.5 and 16.7 g/dl (P > 0.05) for haemoglobin level; 41 and 40 mmol/mol (5.9% and 5.8%; P < 0.01) for HbA1c ; and 5.8 and 5.1 mmol/l (105 and 91.3 mg/dl; P < 0.001) for FPG, respectively. The adjusted relationship between HbA1c and FPG was quadratic at sea level and linear at high altitude. Adjusted models showed that, to predict an HbA1c value of 48 mmol/mol (6.5%), the corresponding mean FPG values at sea level and high altitude were 6.6 and 14.8 mmol/l (120 and 266 mg/dl), respectively. An HbA1c cut-off of 48 mmol/mol (6.5%) had a sensitivity for high FPG of 87.3% (95% confidence interval (95% CI) 76.5 to 94.4) at sea level and 40.9% (95% CI 20.7 to 63.6) at high altitude. CONCLUSION The relationship between HbA1c and FPG is less clear at high altitude than at sea level. Caution is warranted when using HbA1c to diagnose diabetes mellitus in this setting.
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Affiliation(s)
- J. C. Bazo‐Alvarez
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
| | - R. Quispe
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
| | - T. D. Pillay
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
- University College London Medical SchoolLondon School of Hygiene and Tropical MedicineLondonUK
| | - A. Bernabé‐Ortiz
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
| | - L. Smeeth
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
- Faculty of Epidemiology and Population HealthLondon School of Hygiene and Tropical MedicineLondonUK
| | - W. Checkley
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
- Division of Pulmonary and Critical CareJohns Hopkins UniversityBaltimoreMDUSA
| | - R. H. Gilman
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
- Área de Investigación y DesarrolloA.B. PRISMALimaPeru
- Department of International HealthJohns Hopkins Bloomberg School of Public HealthJohns Hopkins UniversityBaltimoreMDUSA
| | - G. Málaga
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
- Department of MedicineUniversidad Peruana Cayetano HerediaLimaPeru
| | - J. J. Miranda
- CRONICAS Centre of Excellence in Chronic DiseasesUniversidad Peruana Cayetano HerediaLimaPeru
- Department of MedicineUniversidad Peruana Cayetano HerediaLimaPeru
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Coldren KM, Li DP, Kline DD, Hasser EM, Heesch CM. Acute hypoxia activates neuroendocrine, but not presympathetic, neurons in the paraventricular nucleus of the hypothalamus: differential role of nitric oxide. Am J Physiol Regul Integr Comp Physiol 2017; 312:R982-R995. [PMID: 28404583 DOI: 10.1152/ajpregu.00543.2016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/06/2017] [Accepted: 04/07/2017] [Indexed: 11/22/2022]
Abstract
Hypoxia results in decreased arterial Po2, arterial chemoreflex activation, and compensatory increases in breathing, sympathetic outflow, and neuroendocrine secretions, including increased secretion of AVP, corticotropin-releasing hormone (CRH), adrenocorticotropin hormone (ACTH), and corticosterone. In addition to a brain stem pathway, including the nucleus tractus solitarius (nTS) and the rostral ventrolateral medulla (RVLM), medullary pathways to the paraventricular nucleus of the hypothalamus (PVN) contribute to chemoreflex responses. Experiments evaluated activation of specific cell phenotypes within the PVN following an acute hypoxic stimulus (AH; 2 h, 10% O2) in conscious rats. Retrograde tracers (from spinal cord and RVLM) labeled presympathetic (PreS) neurons, and immunohistochemistry identified AVP- and CRH-immunoreactive (IR) cells. c-Fos-IR was an index of neuronal activation. Hypoxia activated AVP-IR (~6%) and CRH-IR (~15%) cells, but not PreS cells in the PVN, suggesting that sympathoexcitation during moderate AH is mediated mainly by a pathway that does not include PreS neurons in the PVN. Approximately 14 to 17% of all PVN cell phenotypes examined expressed neuronal nitric oxide synthase (nNOS-IR). AH activated only nNOS-negative AVP-IR neurons. In contrast ~23% of activated CRH-IR neurons in the PVN contained nNOS. In the median eminence, CRH-IR terminals were closely opposed to tanycyte processes and end-feet (vimentin-IR) in the external zone, where vascular NO participates in tanycyte retraction to facilitate neuropeptide secretion into the pituitary portal circulation. Results are consistent with an inhibitory role of NO on AVP and PreS neurons in the PVN and an excitatory role of NO on CRH secretion in the PVN and median eminence.
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Affiliation(s)
- K Max Coldren
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - De-Pei Li
- Department of Critical Care, University of Texas MD Anderson Cancer Center, Houston, Texas
| | - David D Kline
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri.,Interdisciplinary Neuroscience Program, University of Missouri, Columbia, Missouri
| | - Eileen M Hasser
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri; and
| | - Cheryl M Heesch
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri; .,Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri.,Interdisciplinary Neuroscience Program, University of Missouri, Columbia, Missouri
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Behl T, Kotwani A. Downregulated Brain-Derived Neurotrophic Factor-Induced Oxidative Stress in the Pathophysiology of Diabetic Retinopathy. Can J Diabetes 2016; 41:241-246. [PMID: 27913110 DOI: 10.1016/j.jcjd.2016.08.228] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 07/23/2016] [Accepted: 08/31/2016] [Indexed: 12/30/2022]
Abstract
Brain-derived neurotrophic factor (BDNF), a member of neurotrophin growth factor family, physiologically mediates induction of neurogenesis and neuronal differentiation, promotes neuronal growth and survival and maintains synaptic plasticity and neuronal interconnections. Unlike the central nervous system, its secretion in the peripheral nervous system occurs in an activity-dependent manner. BDNF improves neuronal mortality, growth, differentiation and maintenance. It also provides neuroprotection against several noxious stimuli, thereby preventing neuronal damage during pathologic conditions. However, in diabetic retinopathy (a neuromicrovascular disorder involving immense neuronal degeneration), BDNF fails to provide enough neuroprotection against oxidative stress-induced retinal neuronal apoptosis. This review describes the prime reasons for the downregulation of BDNF-mediated neuroprotective actions during hyperglycemia, which renders retinal neurons vulnerable to damaging stimuli, leading to diabetic retinopathy.
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Affiliation(s)
- Tapan Behl
- Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
| | - Anita Kotwani
- Department of Pharmacology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
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15
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Song TT, Bi YH, Gao YQ, Huang R, Hao K, Xu G, Tang JW, Ma ZQ, Kong FP, Coote JH, Chen XQ, Du JZ. Systemic pro-inflammatory response facilitates the development of cerebral edema during short hypoxia. J Neuroinflammation 2016; 13:63. [PMID: 26968975 PMCID: PMC4788817 DOI: 10.1186/s12974-016-0528-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/06/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND High-altitude cerebral edema (HACE) is the severe type of acute mountain sickness (AMS) and life threatening. A subclinical inflammation has been speculated, but the exact mechanisms underlying the HACE are not fully understood. METHODS Human volunteers ascended to high altitude (3860 m, 2 days), and rats were exposed to hypoxia in a hypobaric chamber (5000 m, 2 days). Human acute mountain sickness was evaluated by the Lake Louise Score (LLS), and plasma corticotrophin-releasing hormone (CRH) and cytokines TNF-α, IL-1β, and IL-6 were measured in rats and humans. Subsequently, rats were pre-treated with lipopolysaccharide (LPS, intraperitoneal (ip) 4 mg/kg, 11 h) to induce inflammation prior to 1 h hypoxia (7000 m elevation). TNF-α, IL-1β, IL-6, nitric oxide (NO), CRH, and aquaporin-4 (AQP4) and their gene expression, Evans blue, Na(+)-K(+)-ATPase activity, p65 translocation, and cell swelling were measured in brain by ELISA, Western blotting, Q-PCR, RT-PCR, immunohistochemistry, and transmission electron micrography. MAPKs, NF-κB pathway, and water permeability of primary astrocytes were demonstrated. All measurements were performed with or without LPS challenge. The release of NO, TNF-α, and IL-6 in cultured primary microglia by CRH stimulation with or without PDTC (NF-κB inhibitor) or CP154,526 (CRHR1 antagonist) were measured. RESULTS Hypobaric hypoxia enhanced plasma TNF-α, IL-1β, and IL-6 and CRH levels in human and rats, which positively correlated with AMS. A single LPS injection (ip, 4 mg/kg, 12 h) into rats increased TNF-α and IL-1β levels in the serum and cortex, and AQP4 and AQP4 mRNA expression in cortex and astrocytes, and astrocyte water permeability but did not cause brain edema. However, LPS treatment 11 h prior to 1 h hypoxia (elevation, 7000 m) challenge caused cerebral edema, which was associated with activation of NF-κB and MAPKs, hypoxia-reduced Na(+)-K(+)-ATPase activity and blood-brain barrier (BBB) disruption. Both LPS and CRH stimulated TNF-α, IL-6, and NO release in cultured rat microglia via NF-κB and cAMP/PKA. CONCLUSIONS Preexisting systemic inflammation plus a short severe hypoxia elicits cerebral edema through upregulated AQP4 and water permeability by TLR4 and CRH/CRHR1 signaling. This study revealed that both infection and hypoxia can cause inflammatory response in the brain. Systemic inflammation can facilitate onset of hypoxic cerebral edema through interaction of astrocyte and microglia by activation of TLR4 and CRH/CRHR1 signaling. Anti-inflammatory agents and CRHR1 antagonist may be useful for prevention and treatment of AMS and HACE.
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Affiliation(s)
- Ting-Ting Song
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - Yan-Hua Bi
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - Yu-Qi Gao
- Department of Pathophysiology and High Altitude Physiology, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, 400038, China
| | - Rui Huang
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - Ke Hao
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - Gang Xu
- Department of Pathophysiology and High Altitude Physiology, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, 400038, China
| | - Jia-Wei Tang
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - Zhi-Qiang Ma
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - Fan-Ping Kong
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China
| | - John H Coote
- School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, B15 2TT, UK
| | - Xue-Qun Chen
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China.
| | - Ji-Zeng Du
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, Institute of Neuroscience, School of Medicine, Key Laboratory of Medical Neurobiology of The Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University, Hangzhou, 310058, China.
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