51
|
Divide et impera: How mitochondrial fission in astrocytes rules obesity. Mol Metab 2021; 45:101159. [PMID: 33400974 PMCID: PMC7820126 DOI: 10.1016/j.molmet.2020.101159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/27/2020] [Accepted: 12/28/2020] [Indexed: 12/13/2022] Open
|
52
|
Zhang PN, Zhou MQ, Guo J, Zheng HJ, Tang J, Zhang C, Liu YN, Liu WJ, Wang YX. Mitochondrial Dysfunction and Diabetic Nephropathy: Nontraditional Therapeutic Opportunities. J Diabetes Res 2021; 2021:1010268. [PMID: 34926696 PMCID: PMC8677373 DOI: 10.1155/2021/1010268] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 11/02/2021] [Indexed: 12/12/2022] Open
Abstract
Diabetic nephropathy (DN) is a progressive microvascular diabetic complication. Growing evidence shows that persistent mitochondrial dysfunction contributes to the progression of renal diseases, including DN, as it alters mitochondrial homeostasis and, in turn, affects normal kidney function. Pharmacological regulation of mitochondrial networking is a promising therapeutic strategy for preventing and restoring renal function in DN. In this review, we have surveyed recent advances in elucidating the mitochondrial networking and signaling pathways in physiological and pathological contexts. Additionally, we have considered the contributions of nontraditional therapy that ameliorate mitochondrial dysfunction and discussed their molecular mechanism, highlighting the potential value of nontraditional therapies, such as herbal medicine and lifestyle interventions, in therapeutic interventions for DN. The generation of new insights using mitochondrial networking will facilitate further investigations on nontraditional therapies for DN.
Collapse
Affiliation(s)
- Ping Na Zhang
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Meng Qi Zhou
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Jing Guo
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Hui Juan Zheng
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Jingyi Tang
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Chao Zhang
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Yu Ning Liu
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| | - Wei Jing Liu
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
- Institute of Nephrology and Zhanjiang Key Laboratory of Prevention and Management of Chronic Kidney Disease, Guangdong Medical University, Zhanjiang, China
| | - Yao Xian Wang
- Renal Research Institution of Beijing University of Chinese Medicine and Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Shipping Warehouse No. 5, Beijing 100700, China
| |
Collapse
|
53
|
Kim DY, Cheong HT, Ra CS, Kimura K, Jung BD. Effect of 5-azacytidine (5-aza) on UCP2 expression in human liver and colon cancer cells. Int J Med Sci 2021; 18:2176-2186. [PMID: 33859525 PMCID: PMC8040421 DOI: 10.7150/ijms.56564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/24/2021] [Indexed: 11/26/2022] Open
Abstract
The function of the uncoupling protein 2 (UCP2) is different for each cancer cell. However, the mechanism of expression is still unclear. DNA methylation affects protein expression and is one factor that transforms normal cells into cancer cells. In this study, the hepatocellular carcinoma Hep3B and HepG2 cells and colorectal cancer HT-29 cells were treated with 5-azacytidine (5-aza), a DNA demethylation agent, to observe the modification of UCP2 expression and the methylation degree in the UCP2 promoter region. Promoter basal activity and degree of UCP2 expression were measured in Hep3B, HepG2, and HT-29 cells. In addition, methylation-specific PCR (MSP) was performed to investigate the degree of methylation in the UCP2 promoter region. The methylation region in the UCP2 promoter was confirmed based on bisulfite sequencing. In Hep3B cells in which UCP2 mRNA was not transcribed, the promoter basal activity was significantly higher than in HT-29 or HepG2 cells in which UCP2 mRNA was transcribed. Treatment with 5-aza increased UCP2 expression in Hep3B and HT-29 cells; however, the expression in HepG2 cells was unchanged. The UCP2 promoter in Hep3B cells has numerous methylated regions compared with HT-29 and HepG2 cells. The results of the present study revealed that inhibition of UCP2 expression in Hep3B cells was due to methylation of the promoter region. Investigating the mechanism that induces UCP2 expression in cancer cells is important to understand the function of UCP2, which could aid in cancer treatment.
Collapse
Affiliation(s)
- Dae-Yeon Kim
- College of Veterinary Medicine & Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea
| | - Hee-Tae Cheong
- College of Veterinary Medicine & Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea
| | - Chang-Six Ra
- College of Animal Life Sciences, Kangwon National University, Chuncheon 24341, Korea
| | - Kazuhiro Kimura
- Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Bae Dong Jung
- College of Veterinary Medicine & Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea
| |
Collapse
|
54
|
Transplantation of platelet-derived mitochondria alleviates cognitive impairment and mitochondrial dysfunction in db/db mice. Clin Sci (Lond) 2020; 134:2161-2175. [PMID: 32794577 DOI: 10.1042/cs20200530] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 12/15/2022]
Abstract
Diabetes-associated cognitive impairment (DACI) can increase the risk of major cardiovascular events and death. Neuronal functionality is highly dependent on mitochondria and emerging evidence has shown that mitochondrial transplantation is a potential and effective strategy that can reduce brain injury and associated disorders. Platelets are abundant in blood and can be considered a readily available source of small-size mitochondria. These cells can be easily acquired from the peripheral blood with minimal invasion via simple venipuncture. The present study aimed to investigate whether transplantation of platelet-derived mitochondria (Mito-Plt) could improve DACI. Cognitive behaviors were assessed using the Morris water maze test in db/db mice. The results demonstrated that Mito-Plt was internalized into hippocampal neurons 24 h following intracerebroventricular injection. Importantly, one month following Mito-Plt transplantation, DACI was alleviated in db/db mice and the effect was accompanied with increased mitochondrial number, restored mitochondrial function, attenuated oxidative stress and neuronal apoptosis, as well as decreased accumulation of Aβ and Tau in the hippocampus. Taken together, the data demonstrated that transplantation of Mito-Plt attenuated cognitive impairment and mitochondrial dysfunction in db/db mice. This method may be a potential therapeutic application for the treatment of DACI.
Collapse
|
55
|
Shi Z, Qin M, Huang L, Xu T, Chen Y, Hu Q, Peng S, Peng Z, Qu LN, Chen SG, Tuo QH, Liao DF, Wang XP, Wu RR, Yuan TF, Li YH, Liu XM. Human torpor: translating insights from nature into manned deep space expedition. Biol Rev Camb Philos Soc 2020; 96:642-672. [PMID: 33314677 DOI: 10.1111/brv.12671] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/09/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022]
Abstract
During a long-duration manned spaceflight mission, such as flying to Mars and beyond, all crew members will spend a long period in an independent spacecraft with closed-loop bioregenerative life-support systems. Saving resources and reducing medical risks, particularly in mental heath, are key technology gaps hampering human expedition into deep space. In the 1960s, several scientists proposed that an induced state of suppressed metabolism in humans, which mimics 'hibernation', could be an ideal solution to cope with many issues during spaceflight. In recent years, with the introduction of specific methods, it is becoming more feasible to induce an artificial hibernation-like state (synthetic torpor) in non-hibernating species. Natural torpor is a fascinating, yet enigmatic, physiological process in which metabolic rate (MR), body core temperature (Tb ) and behavioural activity are reduced to save energy during harsh seasonal conditions. It employs a complex central neural network to orchestrate a homeostatic state of hypometabolism, hypothermia and hypoactivity in response to environmental challenges. The anatomical and functional connections within the central nervous system (CNS) lie at the heart of controlling synthetic torpor. Although progress has been made, the precise mechanisms underlying the active regulation of the torpor-arousal transition, and their profound influence on neural function and behaviour, which are critical concerns for safe and reversible human torpor, remain poorly understood. In this review, we place particular emphasis on elaborating the central nervous mechanism orchestrating the torpor-arousal transition in both non-flying hibernating mammals and non-hibernating species, and aim to provide translational insights into long-duration manned spaceflight. In addition, identifying difficulties and challenges ahead will underscore important concerns in engineering synthetic torpor in humans. We believe that synthetic torpor may not be the only option for manned long-duration spaceflight, but it is the most achievable solution in the foreseeable future. Translating the available knowledge from natural torpor research will not only benefit manned spaceflight, but also many clinical settings attempting to manipulate energy metabolism and neurobehavioural functions.
Collapse
Affiliation(s)
- Zhe Shi
- National Clinical Research Center for Mental Disorders, and Department of Psychaitry, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China.,Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China.,State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China.,Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200030, China
| | - Meng Qin
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Lu Huang
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, 510632, China
| | - Tao Xu
- Department of Anesthesiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Ying Chen
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Qin Hu
- College of Life Sciences and Bio-Engineering, Beijing University of Technology, Beijing, 100024, China
| | - Sha Peng
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Zhuang Peng
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Li-Na Qu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Shan-Guang Chen
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Qin-Hui Tuo
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Duan-Fang Liao
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
| | - Xiao-Ping Wang
- National Clinical Research Center for Mental Disorders, and Department of Psychaitry, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Ren-Rong Wu
- National Clinical Research Center for Mental Disorders, and Department of Psychaitry, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Ti-Fei Yuan
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200030, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226000, China
| | - Ying-Hui Li
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Xin-Min Liu
- Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China.,State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China.,Research Center for Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193, China
| |
Collapse
|
56
|
Patel B, New LE, Griffiths JC, Deuchars J, Filippi BM. Inhibition of mitochondrial fission and iNOS in the dorsal vagal complex protects from overeating and weight gain. Mol Metab 2020; 43:101123. [PMID: 33227495 PMCID: PMC7753200 DOI: 10.1016/j.molmet.2020.101123] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 11/17/2020] [Accepted: 11/17/2020] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVES The dorsal vagal complex (DVC) senses insulin and controls glucose homeostasis, feeding behaviour and body weight. Three-days of high-fat diet (HFD) in rats are sufficient to induce insulin resistance in the DVC and impair its ability to regulate feeding behaviour. HFD-feeding is associated with increased dynamin-related protein 1 (Drp1)-dependent mitochondrial fission in the DVC. We investigated the effects that altered Drp1 activity in the DVC has on feeding behaviour. Additionally, we aimed to uncover the molecular events and the neuronal cell populations associated with DVC insulin sensing and resistance. METHODS Eight-week-old male Sprague Dawley rats received DVC stereotactic surgery for brain infusion to facilitate the localised administration of insulin or viruses to express mutated forms of Drp1 or to knockdown inducible nitric oxide synthase (iNOS) in the NTS of the DVC. High-Fat diet feeding was used to cause insulin resistance and obesity. RESULTS We showed that Drp1 activation in the DVC increases weight gain in rats and Drp1 inhibition in HFD-fed rats reduced food intake, weight gain and adipose tissue. Rats expressing active Drp1 in the DVC had higher levels of iNOS and knockdown of DVC iNOS in HFD-fed rats led to a reduction of food intake, weight gain and adipose tissue. Finally, inhibiting mitochondrial fission in DVC astrocytes was sufficient to protect rats from HFD-dependent insulin resistance, hyperphagia, weight gain and fat deposition. CONCLUSION We uncovered new molecular and cellular targets for brain regulation of whole-body metabolism, which could inform new strategies to combat obesity and diabetes.
Collapse
Affiliation(s)
- Bianca Patel
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, United Kingdom
| | - Lauryn E New
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, United Kingdom
| | - Joanne C Griffiths
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, United Kingdom
| | - Jim Deuchars
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, United Kingdom
| | - Beatrice M Filippi
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, United Kingdom.
| |
Collapse
|
57
|
Haigh JL, New LE, Filippi BM. Mitochondrial Dynamics in the Brain Are Associated With Feeding, Glucose Homeostasis, and Whole-Body Metabolism. Front Endocrinol (Lausanne) 2020; 11:580879. [PMID: 33240218 PMCID: PMC7680879 DOI: 10.3389/fendo.2020.580879] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/05/2020] [Indexed: 12/13/2022] Open
Abstract
The brain is responsible for maintaining whole-body energy homeostasis by changing energy input and availability. The hypothalamus and dorsal vagal complex (DVC) are the primary sites of metabolic control, able to sense both hormones and nutrients and adapt metabolism accordingly. The mitochondria respond to the level of nutrient availability by fusion or fission to maintain energy homeostasis; however, these processes can be disrupted by metabolic diseases including obesity and type II diabetes (T2D). Mitochondrial dynamics are crucial in the development and maintenance of obesity and T2D, playing a role in the control of glucose homeostasis and whole-body metabolism across neurons and glia in the hypothalamus and DVC.
Collapse
Affiliation(s)
| | | | - Beatrice M. Filippi
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
| |
Collapse
|
58
|
Bayne M, Alvarsson A, Devarakonda K, Li R, Jimenez-Gonzalez M, Garibay D, Conner K, Varghese M, Serasinghe MN, Chipuk JE, Hof PR, Stanley SA. Repeated hypoglycemia remodels neural inputs and disrupts mitochondrial function to blunt glucose-inhibited GHRH neuron responsiveness. JCI Insight 2020; 5:133488. [PMID: 33148883 PMCID: PMC7710320 DOI: 10.1172/jci.insight.133488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 09/24/2020] [Indexed: 11/29/2022] Open
Abstract
Hypoglycemia is a frequent complication of diabetes, limiting therapy and increasing morbidity and mortality. With recurrent hypoglycemia, the counterregulatory response (CRR) to decreased blood glucose is blunted, resulting in hypoglycemia-associated autonomic failure (HAAF). The mechanisms leading to these blunted effects are only poorly understood. Here, we report, with ISH, IHC, and the tissue-clearing capability of iDISCO+, that growth hormone releasing hormone (GHRH) neurons represent a unique population of arcuate nucleus neurons activated by glucose deprivation in vivo. Repeated glucose deprivation reduces GHRH neuron activation and remodels excitatory and inhibitory inputs to GHRH neurons. We show that low glucose sensing is coupled to GHRH neuron depolarization, decreased ATP production, and mitochondrial fusion. Repeated hypoglycemia attenuates these responses during low glucose. By maintaining mitochondrial length with the small molecule mitochondrial division inhibitor-1, we preserved hypoglycemia sensitivity in vitro and in vivo. Our findings present possible mechanisms for the blunting of the CRR, significantly broaden our understanding of the structure of GHRH neurons, and reveal that mitochondrial dynamics play an important role in HAAF. We conclude that interventions targeting mitochondrial fission in GHRH neurons may offer a new pathway to prevent HAAF in patients with diabetes. GHRH neurons in the arcuate nucleus are activated by glucose deprivation; however, repeated hypoglycemia blunts activation, remodels inputs, and disrupts mitochondrial fusion.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Merina Varghese
- Nash Family Department of Neuroscience and Friedman Brain Institute, and
| | - Madhavika N Serasinghe
- Tisch Cancer Institute and Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jerry E Chipuk
- Tisch Cancer Institute and Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Patrick R Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute, and
| | - Sarah A Stanley
- Diabetes, Obesity and Metabolism Institute.,Nash Family Department of Neuroscience and Friedman Brain Institute, and
| |
Collapse
|
59
|
Quenneville S, Labouèbe G, Basco D, Metref S, Viollet B, Foretz M, Thorens B. Hypoglycemia-Sensing Neurons of the Ventromedial Hypothalamus Require AMPK-Induced Txn2 Expression but Are Dispensable for Physiological Counterregulation. Diabetes 2020; 69:2253-2266. [PMID: 32839348 PMCID: PMC7576557 DOI: 10.2337/db20-0577] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/18/2020] [Indexed: 12/23/2022]
Abstract
The ventromedial nucleus of the hypothalamus (VMN) is involved in the counterregulatory response to hypoglycemia. VMN neurons activated by hypoglycemia (glucose-inhibited [GI] neurons) have been assumed to play a critical although untested role in this response. Here, we show that expression of a dominant negative form of AMPK or inactivation of AMPK α1 and α2 subunit genes in Sf1 neurons of the VMN selectively suppressed GI neuron activity. We found that Txn2, encoding a mitochondrial redox enzyme, was strongly downregulated in the absence of AMPK activity and that reexpression of Txn2 in Sf1 neurons restored GI neuron activity. In cell lines, Txn2 was required to limit glucopenia-induced reactive oxygen species production. In physiological studies, absence of GI neuron activity after AMPK suppression in the VMN had no impact on the counterregulatory hormone response to hypoglycemia or on feeding. Thus, AMPK is required for GI neuron activity by controlling the expression of the antioxidant enzyme Txn2. However, the glucose-sensing capacity of VMN GI neurons is not required for the normal counterregulatory response to hypoglycemia. Instead, it may represent a fail-safe system in case of impaired hypoglycemia sensing by peripherally located glucose detection systems that are connected to the VMN.
Collapse
Affiliation(s)
- Simon Quenneville
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Gwenaël Labouèbe
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Davide Basco
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Salima Metref
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Benoit Viollet
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Marc Foretz
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
60
|
Deficiency of β-carotene oxygenase 2 induces mitochondrial fragmentation and activates the STING-IRF3 pathway in the mouse hypothalamus. J Nutr Biochem 2020; 88:108542. [PMID: 33129969 DOI: 10.1016/j.jnutbio.2020.108542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/23/2020] [Accepted: 10/23/2020] [Indexed: 12/24/2022]
Abstract
Hypothalamic inflammation has been linked to various aspects of central metabolic dysfunction and diseases in humans, including hyperphagia, altered energy expenditure, and obesity. We previously reported that loss of β-carotene oxygenase 2 (BCO2), a mitochondrial inner membrane protein, causes the alteration of the hypothalamic metabolome, low-grade inflammation, and an increase in food intake in mice at an early age, e.g., 3-6 weeks. Here, we determined the extent to which the deficiency of BCO2 induces hypothalamic inflammation in BCO2 knockout mice. Mitochondrial proteomics, electron microscopy, and immunoblotting were used to assess the changes in hypothalamic mitochondrial dynamics and mitochondrial DNA sensing and signaling. The results showed that deficiency of BCO2 altered hypothalamic mitochondrial proteome and respiratory supercomplex assembly by enhancing the expression of NADH:ubiquinone oxidoreductase subunit A11 protein and improved cardiolipin synthesis. BCO2 deficiency potentiated mitochondrial fission but suppressed mitophagy and mitochondrial biogenesis. Furthermore, deficiency of BCO2 resulted in inactivation of mitochondrial MnSOD enzyme, excessive production of reactive oxygen species, and elevation of protein levels of stimulator of interferon genes (STING) and interferon regulatory factor 3 (IRF3) in the hypothalamus. The data suggest that BCO2 is essential for hypothalamic mitochondrial dynamics. BCO2 deficiency induces mitochondrial fragmentation and mitochondrial oxidative stress, which may lead to mitochondrial DNA release into the cytosol and subsequently sensing by activation of the STING-IRF3 signaling pathway in the mouse hypothalamus.
Collapse
|
61
|
Sohn JW, Ho WK. Cellular and systemic mechanisms for glucose sensing and homeostasis. Pflugers Arch 2020; 472:1547-1561. [PMID: 32960363 DOI: 10.1007/s00424-020-02466-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/14/2020] [Accepted: 09/14/2020] [Indexed: 12/25/2022]
Abstract
Glucose is a major source of energy in animals. Maintaining blood glucose levels within a physiological range is important for facilitating glucose uptake by cells, as required for optimal functioning. Glucose homeostasis relies on multiple glucose-sensing cells in the body that constantly monitor blood glucose levels and respond accordingly to adjust its glycemia. These include not only pancreatic β-cells and α-cells that secrete insulin and glucagon, but also central and peripheral neurons regulating pancreatic endocrine function. Different types of cells respond distinctively to changes in blood glucose levels, and the mechanisms involved in glucose sensing are diverse. Notably, recent studies have challenged the currently held views regarding glucose-sensing mechanisms. Furthermore, peripheral and central glucose-sensing cells appear to work in concert to control blood glucose level and maintain glucose and energy homeostasis in organisms. In this review, we summarize the established concepts and recent advances in the understanding of cellular and systemic mechanisms that regulate glucose sensing and its homeostasis.
Collapse
Affiliation(s)
- Jong-Woo Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, South Korea.
| | - Won-Kyung Ho
- Department of Physiology, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, South Korea.
- Department of Brain and Cognitive Sciences, Seoul National University College of Natural Sciences, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
| |
Collapse
|
62
|
He M, Ma Y, Wang R, Zhang J, Jing L, Li PA. Deletion of Mitochondrial Uncoupling Protein 2 Exacerbates Mitochondrial Damage in Mice Subjected to Cerebral Ischemia and Reperfusion Injury under both Normo- and Hyperglycemic Conditions. Int J Biol Sci 2020; 16:2788-2802. [PMID: 33061796 PMCID: PMC7545711 DOI: 10.7150/ijbs.48204] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 08/06/2020] [Indexed: 12/22/2022] Open
Abstract
Deletion of mitochondrial uncoupling protein 2 (UCP2) has been shown to aggravate ischemic damage in the brain. However, the underlying mechanisms are not fully understood. The objective of this study is to explore the impact of homozygous UCP2 deletion (UCP2-/-) on mitochondrial fission and fusion dynamic balance in ischemic mice under normo- and hyperglycemic conditions. UCP2-/- and wildtype mice were subjected to a 60 min middle cerebral artery occlusion (MCAO) and allowed reperfusion for 6h, 24h and 72h. Our results demonstrated that deletion of UCP2 enlarged infarct volumes and increased numbers of cell death in both normo- and hyperglycemic ischemic mice compared with their wildtype counterparts subjected to the same duration of ischemia and reperfusion. The detrimental effects of UCP deletion were associated with increased ROS production, elevated mitochondrial fission markers Drp1 and Fis1 and suppressed fusion markers Opa1 and Mfn2 in UCP2-/- mice. Electron microscopic study demonstrated a marked mitochondrial swolling after 6h of reperfusion in UCP2-/- mice, contrasting to a mild mitochondrial swolling in wildtype ischemic animals. It is concluded that the exacerbating effects of UCP2-/- on ischemic outcome in both normo- and hyperglycemic animals are associated with increased ROS production, disturbed mitochondrial dynamic balance towards fission and early damage to mitochondrial ultrastructure.
Collapse
Affiliation(s)
- Maotao He
- Department of Pathology, General Hospital of Ningxia Medical University, Yinchuan, Ningxia 750004, China.,School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China.,Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technological Enterprise (BRITE), College of Health and Sciences, North Carolina Central University, Durham, NC 27707, USA
| | - Yanmei Ma
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Rui Wang
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Jianzhong Zhang
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Li Jing
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - P Andy Li
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technological Enterprise (BRITE), College of Health and Sciences, North Carolina Central University, Durham, NC 27707, USA
| |
Collapse
|
63
|
De Miguel C, Hamrick WC, Sedaka R, Jagarlamudi S, Asico LD, Jose PA, Cuevas S. Uncoupling Protein 2 Increases Blood Pressure in DJ -1 Knockout Mice. J Am Heart Assoc 2020; 8:e011856. [PMID: 30995881 PMCID: PMC6512091 DOI: 10.1161/jaha.118.011856] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background The redox-sensitive chaperone DJ -1 and uncoupling protein 2 are protective against mitochondrial oxidative stress. We previously reported that renal-selective depletion and germline deletion of DJ -1 increases blood pressure in mice. This study aimed to determine the mechanisms involved in the oxidative stress-mediated hypertension in DJ -1 -/- mice. Methods and Results There were no differences in sodium excretion, renal renin expression, renal NADPH oxidase activity, and serum creatinine levels between DJ -1 -/- and wild-type mice. Renal expression of nitro-tyrosine, malondialdehyde, and urinary kidney injury marker-1 were increased in DJ -1 -/- mice relative to wild-type littermates. mRNA expression of mitochondrial heat shock protein 60 was also elevated in kidneys from DJ -1 -/- mice, indicating the presence of oxidative stress. Tempol-treated DJ -1 -/- mice presented higher serum nitrite/nitrate levels than vehicle-treated DJ -1 -/- mice, suggesting a role of the NO system in the high blood pressure of this model. Tempol treatment normalized renal kidney injury marker-1 and malondialdehyde expression as well as blood pressure in DJ -1 -/- mice, but had no effect in wild-type mice. The renal Ucp2 mRNA expression was increased in DJ -1 -/- mice versus wild-type and was also normalized by tempol. The renal-selective silencing of Ucp2 led to normalization of blood pressure and serum nitrite/nitrate ratio in DJ -1 -/- mice. Conclusions The deletion of DJ -1 leads to oxidative stress-induced hypertension associated with downregulation of NO function, and overexpression of Ucp2 in the kidney increases blood pressure in DJ -1 -/- mice. To our knowledge, this is the first report providing evidence of the role of uncoupling protein 2 in blood pressure regulation.
Collapse
Affiliation(s)
- Carmen De Miguel
- 1 Section of Cardio-Renal Physiology and Medicine Division of Nephrology Department of Medicine University of Alabama at Birmingham AL
| | - William C Hamrick
- 1 Section of Cardio-Renal Physiology and Medicine Division of Nephrology Department of Medicine University of Alabama at Birmingham AL
| | - Randee Sedaka
- 1 Section of Cardio-Renal Physiology and Medicine Division of Nephrology Department of Medicine University of Alabama at Birmingham AL
| | - Sudha Jagarlamudi
- 2 Division of Renal Diseases & Hypertension Department of Medicine The George Washington University School of Medicine and Health Sciences Washington DC
| | - Laureano D Asico
- 2 Division of Renal Diseases & Hypertension Department of Medicine The George Washington University School of Medicine and Health Sciences Washington DC
| | - Pedro A Jose
- 2 Division of Renal Diseases & Hypertension Department of Medicine The George Washington University School of Medicine and Health Sciences Washington DC
| | - Santiago Cuevas
- 3 Research Center for Genetic Medicine Children's National Health System Washington DC
| |
Collapse
|
64
|
Stoelzel CR, Zhang Y, Cincotta AH. Circadian-timed dopamine agonist treatment reverses high-fat diet-induced diabetogenic shift in ventromedial hypothalamic glucose sensing. Endocrinol Diabetes Metab 2020; 3:e00139. [PMID: 32704560 PMCID: PMC7375120 DOI: 10.1002/edm2.139] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 03/28/2020] [Indexed: 12/19/2022] Open
Abstract
INTRODUCTION Within the ventromedial hypothalamus (VMH), glucose inhibitory (GI) neurons sense hypoglycaemia while glucose excitatory (GE) neurons sense hyperglycaemia to initiate counter control mechanisms under normal conditions. However, potential electrophysiological alterations of these two neuronal types in vivo in insulin-resistant states have never been simultaneously fully documented. Further, the anti-diabetic effect of dopamine agonism on this VMH system under insulin resistance has not been studied. METHODS This study examined the impact of a high-fat diet (HFD) on in vivo electrophysiological recordings from VMH GE and GI neurons and the ability of circadian-timed dopamine agonist therapy to reverse any adverse effect of the HFD on such VMH activities and peripheral glucose metabolism. RESULTS HFD significantly inhibited VMH GE neuronal electrophysiological response to local hyperglycaemia (36.3%) and augmented GI neuronal excitation response to local hypoglycaemia (47.0%). Bromocriptine (dopamine agonist) administration at onset of daily activity (but not during the daily sleep phase) completely reversed both VMH GE and GI neuronal aberrations induced by HFD. Such timed treatment also normalized glucose intolerance and insulin resistance. These VMH and peripheral glucose metabolism effects of circadian-timed bromocriptine may involve its known effect to reduce elevated VMH noradrenergic activity in insulin-resistant states as local VMH administration of norepinephrine was observed to significantly inhibit VMH GE neuronal sensing of local hyperglycaemia in insulin-sensitive animals on regular chow diet (52.4%). CONCLUSIONS HFD alters VMH glucose sensing in a manner that potentiates hyperglycaemia and this effect on the VMH can be reversed by appropriately circadian-timed dopamine agonist administration.
Collapse
|
65
|
Flak JN, Goforth PB, Dell’Orco J, Sabatini PV, Li C, Bozadjieva N, Sorensen M, Valenta A, Rupp A, Affinati AH, Cras-Méneur C, Ansari A, Sacksner J, Kodur N, Sandoval DA, Kennedy RT, Olson DP, Myers MG. Ventromedial hypothalamic nucleus neuronal subset regulates blood glucose independently of insulin. J Clin Invest 2020; 130:2943-2952. [PMID: 32134398 PMCID: PMC7260001 DOI: 10.1172/jci134135] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 02/20/2020] [Indexed: 12/14/2022] Open
Abstract
To identify neurons that specifically increase blood glucose from among the diversely functioning cell types in the ventromedial hypothalamic nucleus (VMN), we studied the cholecystokinin receptor B-expressing (CCKBR-expressing) VMN targets of glucose-elevating parabrachial nucleus neurons. Activation of these VMNCCKBR neurons increased blood glucose. Furthermore, although silencing the broader VMN decreased energy expenditure and promoted weight gain without altering blood glucose levels, silencing VMNCCKBR neurons decreased hIepatic glucose production, insulin-independently decreasing blood glucose without altering energy balance. Silencing VMNCCKBR neurons also impaired the counterregulatory response to insulin-induced hypoglycemia and glucoprivation and replicated hypoglycemia-associated autonomic failure. Hence, VMNCCKBR cells represent a specialized subset of VMN cells that function to elevate glucose. These cells not only mediate the allostatic response to hypoglycemia but also modulate the homeostatic setpoint for blood glucose in an insulin-independent manner, consistent with a role for the brain in the insulin-independent control of glucose homeostasis.
Collapse
Affiliation(s)
| | - Paulette B. Goforth
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan, USA
| | | | | | - Chien Li
- Novo Nordisk, Seattle, Washington, USA
| | | | | | | | | | | | | | | | | | | | | | | | - David P. Olson
- Division of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
| | | |
Collapse
|
66
|
Chiurazzi M, Di Maro M, Cozzolino M, Colantuoni A. Mitochondrial Dynamics and Microglia as New Targets in Metabolism Regulation. Int J Mol Sci 2020; 21:ijms21103450. [PMID: 32414136 PMCID: PMC7279384 DOI: 10.3390/ijms21103450] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 12/15/2022] Open
Abstract
Energy homeostasis regulation is essential for the maintenance of life. Neuronal hypothalamic populations are involved in the regulation of energy balance. In order play this role, they require energy: mitochondria, indeed, have a key role in ensuring a constant energy supply to neurons. Mitochondria are cellular organelles that are involved in dynamic processes; their dysfunction has been associated with many diseases, such as obesity and type 2 diabetes, indicating their importance in cellular metabolism and bioenergetics. Food intake excess can induce mitochondrial dysfunction with consequent production of reactive oxygen species (ROS) and oxidative stress. Several studies have shown the involvement of mitochondrial dynamics in the modulation of releasing agouti-related protein (AgRP) and proopiomelanocortin (POMC) neuronal activity, although the mechanisms are still unclear. However, recent studies have shown that changes in mitochondrial metabolism, such as in inflammation, can contribute also to the activation of the microglial system in several diseases, especially degenerative diseases. This review is aimed to summarize the link between mitochondrial dynamics and hypothalamic neurons in the regulation of glucose and energy homeostasis. Furthermore, we focus on the importance of microglia activation in the pathogenesis of many diseases, such as obesity, and on the relationship with mitochondrial dynamics, although this process is still largely unknown.
Collapse
Affiliation(s)
- Martina Chiurazzi
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Clinical Medicine and Surgery, University of Naples “Federico II”, 80131 Naples, Italy; (M.D.M.); (A.C.)
- Correspondence: ; Tel.: +39-388-372-4757
| | - Martina Di Maro
- Department of Clinical Medicine and Surgery, University of Naples “Federico II”, 80131 Naples, Italy; (M.D.M.); (A.C.)
| | - Mauro Cozzolino
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT 06520, USA;
- Department of Obstetrics and Gynecology, Rey Juan Carlos University, Calle Tulipán, Móstoles, 28933 Madrid, Spain
- IVIRMA, IVI Foundation, Health Research Institute La Fe, Avenida Fernando Abril Martorell, 106, 46026 Valencia, Spain
| | - Antonio Colantuoni
- Department of Clinical Medicine and Surgery, University of Naples “Federico II”, 80131 Naples, Italy; (M.D.M.); (A.C.)
| |
Collapse
|
67
|
He Y, Xu P, Wang C, Xia Y, Yu M, Yang Y, Yu K, Cai X, Qu N, Saito K, Wang J, Hyseni I, Robertson M, Piyarathna B, Gao M, Khan SA, Liu F, Chen R, Coarfa C, Zhao Z, Tong Q, Sun Z, Xu Y. Estrogen receptor-α expressing neurons in the ventrolateral VMH regulate glucose balance. Nat Commun 2020; 11:2165. [PMID: 32358493 PMCID: PMC7195451 DOI: 10.1038/s41467-020-15982-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/06/2020] [Indexed: 12/20/2022] Open
Abstract
Brain glucose-sensing neurons detect glucose fluctuations and prevent severe hypoglycemia, but mechanisms mediating functions of these glucose-sensing neurons are unclear. Here we report that estrogen receptor-α (ERα)-expressing neurons in the ventrolateral subdivision of the ventromedial hypothalamic nucleus (vlVMH) can sense glucose fluctuations, being glucose-inhibited neurons (GI-ERαvlVMH) or glucose-excited neurons (GE-ERαvlVMH). Hypoglycemia activates GI-ERαvlVMH neurons via the anoctamin 4 channel, and inhibits GE-ERαvlVMH neurons through opening the ATP-sensitive potassium channel. Further, we show that GI-ERαvlVMH neurons preferentially project to the medioposterior arcuate nucleus of the hypothalamus (mpARH) and GE-ERαvlVMH neurons preferentially project to the dorsal Raphe nuclei (DRN). Activation of ERαvlVMH to mpARH circuit and inhibition of ERαvlVMH to DRN circuit both increase blood glucose. Thus, our results indicate that ERαvlVMH neurons detect glucose fluctuations and prevent severe hypoglycemia in mice.
Collapse
Affiliation(s)
- Yanlin He
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Pingwen Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Chunmei Wang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Yan Xia
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Meng Yu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Yongjie Yang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Kaifan Yu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Xing Cai
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Na Qu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Kenji Saito
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Julia Wang
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Ilirjana Hyseni
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Matthew Robertson
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Badrajee Piyarathna
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Min Gao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Sohaib A Khan
- Department of Cell and Cancer Biology, Vontz Center for Molecular Studies, University of Cincinnati, College of Medicine, Cincinnati, OH, 45267, USA
| | - Feng Liu
- Departments of Pharmacology, University of Texas Health at San Antonio, San Antonio, TX, 78229, USA
| | - Rui Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Cristian Coarfa
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Zhongming Zhao
- Center for Precision Health, School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Zheng Sun
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.
| |
Collapse
|
68
|
Hanna L, Kawalek TJ, Beall C, Ellacott KLJ. Changes in neuronal activity across the mouse ventromedial nucleus of the hypothalamus in response to low glucose: Evaluation using an extracellular multi-electrode array approach. J Neuroendocrinol 2020; 32:e12824. [PMID: 31880369 PMCID: PMC7064989 DOI: 10.1111/jne.12824] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/04/2019] [Accepted: 12/23/2019] [Indexed: 01/01/2023]
Abstract
The hypothalamic ventromedial nucleus (VMN) is involved in maintaining systemic glucose homeostasis. Neurophysiological studies in rodent brain slices have identified populations of VMN glucose-sensing neurones: glucose-excited (GE) neurones, cells which increased their firing rate in response to increases in glucose concentration, and glucose-inhibited (GI) neurones, which show a reduced firing frequency in response to increasing glucose concentrations. To date, most slice electrophysiological studies characterising VMN glucose-sensing neurones in rodents have utilised the patch clamp technique. Multi-electrode arrays (MEAs) are a state-of-the-art electrophysiological tool enabling the electrical activity of many cells to be recorded across multiple electrode sites (channels) simultaneously. We used a perforated MEA (pMEA) system to evaluate electrical activity changes across the dorsal-ventral extent of the mouse VMN region in response to alterations in glucose concentration. Because intrinsic (ie, direct postsynaptic sensing) and extrinsic (ie, presynaptically modulated) glucosensation were not discriminated, we use the terminology 'GE/presynaptically excited by an increase (PER)' and 'GI/presynaptically excited by a decrease (PED)' in the present study to describe responsiveness to changes in extracellular glucose across the mouse VMN. We observed that 15%-60% of channels were GE/PER, whereas 2%-7% were GI/PED channels. Within the dorsomedial portion of the VMN (DM-VMN), significantly more channels were GE/PER compared to the ventrolateral portion of the VMN (VL-VMN). However, GE/PER channels within the VL-VMN showed a significantly higher basal firing rate in 2.5 mmol l-1 glucose than DM-VMN GE/PER channels. No significant difference in the distribution of GI/PED channels was observed between the VMN subregions. The results of the present study demonstrate the utility of the pMEA approach for evaluating glucose responsivity across the mouse VMN. pMEA studies could be used to refine our understanding of other neuroendocrine systems by examining population level changes in electrical activity across brain nuclei, thus providing key functional neuroanatomical information to complement and inform the design of single-cell neurophysiological studies.
Collapse
Affiliation(s)
- Lydia Hanna
- Reading School of PharmacyUniversity of ReadingReadingUK
- Institute of Biomedical & Clinical SciencesUniversity of Exeter Medical SchoolExeterUK
- Present address:
Department of Biological SciencesCentre for Biomedical SciencesRoyal Holloway University of LondonEghamUK
| | - Tristan J. Kawalek
- Institute of Biomedical & Clinical SciencesUniversity of Exeter Medical SchoolExeterUK
| | - Craig Beall
- Institute of Biomedical & Clinical SciencesUniversity of Exeter Medical SchoolExeterUK
| | - Kate L. J. Ellacott
- Institute of Biomedical & Clinical SciencesUniversity of Exeter Medical SchoolExeterUK
| |
Collapse
|
69
|
Fu H, Zhou H, Yu X, Xu J, Zhou J, Meng X, Zhao J, Zhou Y, Chisholm AD, Xu S. Wounding triggers MIRO-1 dependent mitochondrial fragmentation that accelerates epidermal wound closure through oxidative signaling. Nat Commun 2020; 11:1050. [PMID: 32103012 PMCID: PMC7044169 DOI: 10.1038/s41467-020-14885-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/10/2020] [Indexed: 12/19/2022] Open
Abstract
Organisms respond to tissue damage through the upregulation of protective responses which restore tissue structure and metabolic function. Mitochondria are key sources of intracellular oxidative metabolic signals that maintain cellular homeostasis. Here we report that tissue and cellular wounding triggers rapid and reversible mitochondrial fragmentation. Elevated mitochondrial fragmentation either in fzo-1 fusion-defective mutants or after acute drug treatment accelerates actin-based wound closure. Wounding triggered mitochondrial fragmentation is independent of the GTPase DRP-1 but acts via the mitochondrial Rho GTPase MIRO-1 and cytosolic Ca2+. The fragmented mitochondria and accelerated wound closure of fzo-1 mutants are dependent on MIRO-1 function. Genetic and transcriptomic analyzes show that enhanced mitochondrial fragmentation accelerates wound closure via the upregulation of mtROS and Cytochrome P450. Our results reveal how mitochondrial dynamics respond to cellular and tissue injury and promote tissue repair. Mitochondria are important organelles that generate and respond to signals to maintain cellular homeostasis. Here the authors show that wounding triggers GTPase MIRO-1- and calcium-dependent mitochondrial fragmentation, which aids tissue wound repair through cytochrome P450 and mitochondrial reactive oxygen species.
Collapse
Affiliation(s)
- Hongying Fu
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Hengda Zhou
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China.,The Zhejiang University-University of Edinburgh Institute, 718 East Haizhou Rd., Haining, 314400, Zhejiang, China
| | - Xinghai Yu
- Department of System Biology, School of Life Science, Wuhan University, 430072, Wuhan, China
| | - Jingxiu Xu
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China.,The Zhejiang University-University of Edinburgh Institute, 718 East Haizhou Rd., Haining, 314400, Zhejiang, China
| | - Jinghua Zhou
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Xinan Meng
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Jianzhi Zhao
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Yu Zhou
- Department of System Biology, School of Life Science, Wuhan University, 430072, Wuhan, China
| | - Andrew D Chisholm
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Suhong Xu
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China. .,The Zhejiang University-University of Edinburgh Institute, 718 East Haizhou Rd., Haining, 314400, Zhejiang, China. .,Women's Hospital of Zhejiang University, School of Medicine Hangzhou, 310058, Hangzhou, China.
| |
Collapse
|
70
|
Mitophagy in Acute Kidney Injury and Kidney Repair. Cells 2020; 9:cells9020338. [PMID: 32024113 PMCID: PMC7072358 DOI: 10.3390/cells9020338] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/24/2020] [Accepted: 01/25/2020] [Indexed: 12/13/2022] Open
Abstract
Acute kidney injury (AKI) is a major kidney disease characterized by rapid decline of renal function. Besides its acute consequence of high mortality, AKI has recently been recognized as an independent risk factor for chronic kidney disease (CKD). Maladaptive or incomplete repair of renal tubules after severe or episodic AKI leads to renal fibrosis and, eventually, CKD. Recent studies highlight a key role of mitochondrial pathology in AKI development and abnormal kidney repair after AKI. As such, timely elimination of damaged mitochondria in renal tubular cells represents an important quality control mechanism for cell homeostasis and survival during kidney injury and repair. Mitophagy is a selective form of autophagy that selectively removes redundant or damaged mitochondria. Here, we summarize our recent understanding on the molecular mechanisms of mitophagy, discuss the role of mitophagy in AKI development and kidney repair after AKI, and present future research directions and therapeutic potential.
Collapse
|
71
|
Da Li, Cao T, Sun X, Jin S, Di Xie, Huang X, Yang X, Carmichael GG, Taylor HS, Diano S, Huang Y. Hepatic TET3 contributes to type-2 diabetes by inducing the HNF4α fetal isoform. Nat Commun 2020; 11:342. [PMID: 31953394 PMCID: PMC6969024 DOI: 10.1038/s41467-019-14185-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 12/19/2019] [Indexed: 02/06/2023] Open
Abstract
Precise control of hepatic glucose production (HGP) is pivotal to maintain systemic glucose homeostasis. HNF4α functions to stimulate transcription of key gluconeogenic genes. HNF4α harbors two promoters (P2 and P1) thought to be primarily active in fetal and adult livers, respectively. Here we report that the fetal version of HNF4α is required for HGP in the adult liver. This isoform is acutely induced upon fasting and chronically increased in type-2 diabetes (T2D). P2 isoform induction occurs in response to glucagon-stimulated upregulation of TET3, not previously shown to be involved in HGP. TET3 is recruited to the P2 promoter by FOXA2, leading to promoter demethylation and increased transcription. While TET3 overexpression augments HGP, knockdown of either TET3 or the P2 isoform alone in the liver improves glucose homeostasis in dietary and genetic mouse models of T2D. These studies unmask an unanticipated, conserved regulatory mechanism in HGP and offer potential therapeutic targets for T2D.
Collapse
Affiliation(s)
- Da Li
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
- Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, 110004, China
| | - Tiefeng Cao
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
- Department of Obstetrics and Gynecology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, 510070, China
| | - Xiaoli Sun
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
- Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Affiliated Hospital of Nantong University, Jiangsu, 226001, China
| | - Sungho Jin
- Departments of Cellular and Molecular Physiology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06520, USA
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Di Xie
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
- Center of Reproductive Medicine, Department of Obstetrics and Gynecology, General Hospital of Central Theater Command, Wuhan, Hubei, 430070, China
| | - Xinmei Huang
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
- Department of Endocrinology, Fifth People's Hospital of Shanghai, Fudan University School of Medicine, Shanghai, 200080, China
| | - Xiaoyong Yang
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Gordon G Carmichael
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, CT, 06030, USA
| | - Hugh S Taylor
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Sabrina Diano
- Departments of Cellular and Molecular Physiology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06520, USA
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Yingqun Huang
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, 06510, USA.
| |
Collapse
|
72
|
Bartolome F, Antequera D, de la Cueva M, Rubio-Fernandez M, Castro N, Pascual C, Camins A, Carro E. Endothelial-specific deficiency of megalin in the brain protects mice against high-fat diet challenge. J Neuroinflammation 2020; 17:22. [PMID: 31937343 PMCID: PMC6961312 DOI: 10.1186/s12974-020-1702-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 01/06/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The increasing risk of obesity and diabetes among other metabolic disorders are the consequence of shifts in dietary patterns with high caloric-content food intake. We previously reported that megalin regulates energy homeostasis using blood-brain barrier (BBB) endothelial megalin-deficient (EMD) mice, since these animals developed obesity and metabolic syndrome upon normal chow diet administration. Obesity in mid-life appears to be related to greater dementia risk and represents an increasing global health issue. We demonstrated that EMD phenotype induced impaired learning ability and recognition memory, neurodegeneration, neuroinflammation, reduced neurogenesis, and mitochondrial deregulation associated with higher mitochondrial mass in cortical tissues. METHODS EMD mice were subjected to normal chow and high-fat diet (HFD) for 14 weeks and metabolic changes were evaluated. RESULTS Surprisingly, BBB megalin deficiency protected against HFD-induced obesity improving glucose tolerance and preventing hepatic steatosis. Compared to wild type (wt), the brain cortex in EMD mice showed increased levels of the mitochondrial biogenesis regulator, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), and uncoupling protein 2 (UCP2), a thermogenic protein involved in the regulation of energy metabolism. This agreed with the previously found increased mitochondrial mass in the transgenic mice. Upon HFD challenge, we demonstrated these two proteins were found elevated in wt mice but reported no changes over the already increased levels in EMD animals. CONCLUSION We propose a protective role for megalin on diet-induce obesity, suggesting this could be related to metabolic disturbances found in dementia through brain endocrine system communications.
Collapse
Affiliation(s)
- Fernando Bartolome
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain. .,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain.
| | - Desiree Antequera
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain.,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain
| | - Macarena de la Cueva
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain.,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain
| | - Marcos Rubio-Fernandez
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain.,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain
| | - Nerea Castro
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain.,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain
| | - Consuelo Pascual
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain.,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain
| | - Antoni Camins
- Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain.,Unitat de Farmacologia i Farmacognosia, Facultat de Farmacia, Institut de Biomedicina de la UB (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Eva Carro
- Neurodegenerative Disorders Group, Instituto de Investigacion Hospital 12 de Octubre (i+12), Avda de Cordoba s/n, 28041, Madrid, Spain. .,Network Center for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain.
| |
Collapse
|
73
|
He M, Zhang T, Fan Y, Ma Y, Zhang J, Jing L, Li PA. Deletion of mitochondrial uncoupling protein 2 exacerbates mitophagy and cell apoptosis after cerebral ischemia and reperfusion injury in mice. Int J Med Sci 2020; 17:2869-2878. [PMID: 33162815 PMCID: PMC7645345 DOI: 10.7150/ijms.49849] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 09/27/2020] [Indexed: 12/24/2022] Open
Abstract
Objective: Uncoupling protein 2 (UCP2) is a member of inner mitochondrial membrane proteins and deletion of UCP2 exacerbates brain damage after cerebral ischemia/reperfusion (I/R). Nevertheless, its functional role during cerebral I/R is not entirely understood. The objective of present study was to explore the influence of UCP2 deletion on mitochondrial autophagy (mitophagy) and mitochondria-mediated cell death pathway after cerebral I/R. Methods: UCP2-/- and wildtype (WT) mice were subjected to 60 min middle cerebral artery occlusion (MCAO) and allowed reperfusion for 24 hours. Infarct volume and histological outcomes were assessed, reactive oxygen species (ROS) and autophagy markers were measured, and mitochondrial ultrastructure was examined. Results: Deletion of UCP2 enlarged infarct volume, increased numbers of necrotic and TUNEL positive cells, and significantly increased pro-apoptotic protein levels in UCP2-/- mice compared with WT mice subjected to the same duration of I/R. Further, deletion of UCP2 increased ROS production, elevated LC3, Beclin1 and PINK1, while it suppressed p62 compared with respective WT ischemic controls. Electron microscopic study demonstrated the number of autophagosomes was higher in the UCP2-/- group, compared with the WT group. Conclusions: It is concluded that deletion of UCP2 exacerbates cerebral I/R injury via reinforcing mitophagy and cellular apoptosis in mice.
Collapse
Affiliation(s)
- Maotao He
- Department of Pathology, General Hospital of Ningxia Medical University, Yinchuan, Ningxia 750004, China.,School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China.,Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technological Enterprise (BRITE), College of Health and Sciences, North Carolina Central University, Durham, NC 27707, USA
| | - Ting Zhang
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Yucheng Fan
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Yanmei Ma
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Jianzhong Zhang
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - Li Jing
- School of Basic Medical Sciences, Department of Pathology, Ningxia Medical University; Ningxia Key Laboratory of Vascular Injury and Repair, Yinchuan, Ningxia 750004, China
| | - P Andy Li
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technological Enterprise (BRITE), College of Health and Sciences, North Carolina Central University, Durham, NC 27707, USA
| |
Collapse
|
74
|
Kim JD, Yoon NA, Jin S, Diano S. Microglial UCP2 Mediates Inflammation and Obesity Induced by High-Fat Feeding. Cell Metab 2019; 30:952-962.e5. [PMID: 31495690 PMCID: PMC7251564 DOI: 10.1016/j.cmet.2019.08.010] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 05/01/2019] [Accepted: 08/09/2019] [Indexed: 11/19/2022]
Abstract
Microglia play a crucial role in immune responses, including inflammation. Diet-induced obesity (DIO) triggers microglia activation and hypothalamic inflammation as early as 3 days after high-fat diet (HFD) exposure, before changes in body weight occur. The intracellular mechanism(s) responsible for HFD-induced microglia activation is ill defined. Here, we show that in vivo, HFD induced a rapid and transient increase in uncoupling protein 2 (Ucp2) mRNA expression together with changes in mitochondrial dynamics. Selective microglial deletion of Ucp2 prevented changes in mitochondrial dynamics and function, microglia activation, and hypothalamic inflammation. In association with these, male and female mice were protected from HFD-induced obesity, showing decreased feeding and increased energy expenditure that were associated with changes in the synaptic input organization and activation of the anorexigenic hypothalamic POMC neurons and astrogliosis. Together, our data point to a fuel-availability-driven mitochondrial mechanism as a major player of microglia activation in the central regulation of DIO.
Collapse
Affiliation(s)
- Jung Dae Kim
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Nal Ae Yoon
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Sungho Jin
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Sabrina Diano
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples 80131, Italy.
| |
Collapse
|
75
|
Lizarbe B, Fernández-Pérez A, Caz V, Largo C, Vallejo M, López-Larrubia P, Cerdán S. Systemic Glucose Administration Alters Water Diffusion and Microvascular Blood Flow in Mouse Hypothalamic Nuclei - An fMRI Study. Front Neurosci 2019; 13:921. [PMID: 31551685 PMCID: PMC6733885 DOI: 10.3389/fnins.2019.00921] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 08/16/2019] [Indexed: 12/23/2022] Open
Abstract
The hypothalamus is the principal regulator of global energy balance, enclosing additionally essential neuronal centers for glucose-sensing and osmoregulation. Disturbances in these tightly regulated neuronal networks are thought to underlie the development of severe pandemic syndromes, including obesity and diabetes. In this work, we investigate in vivo the response of individual hypothalamic nuclei to the i.p. administration of glucose or vehicle solutions, using two groups of adult male C57BL6/J fasted mice and a combination of non-invasive T2∗-weighted and diffusion-weighted functional magnetic resonance imaging (fMRI) approaches. MRI parameters were assessed in both groups of animals before, during and in a post-stimulus phase, following the administration of glucose or vehicle solutions. Hypothalamic nuclei depicted different patterns of activation characterized by: (i) generalized glucose-induced increases of neuronal activation and perfusion-markers in the lateral hypothalamus, arcuate and dorsomedial nuclei, (ii) cellular shrinking events and decreases in microvascular blood flow in the dorsomedial, ventromedial and lateral hypothalamus, following the administration of vehicle solutions and (iii) increased neuronal activity markers and decreased microperfusion parameters in the ARC nuclei of vehicle-administered animals. Immunohistochemical studies performed after the post-stimulus phase confirmed the presence of c-Fos immunoreactive neurons in the arcuate nucleus (ARC) from both animal groups, with significantly higher numbers in the glucose-treated animals. Together, our results reveal that fMRI methods are able to detect in vivo diverse patterns of glucose or vehicle-induced effects in the different hypothalamic nuclei.
Collapse
Affiliation(s)
- Blanca Lizarbe
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain
| | - Antonio Fernández-Pérez
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (Ciberdem), Instituto de Salud Carlos III, Madrid, Spain
| | - Victor Caz
- Departamento de Cirugía Experimental, Instituto de Investigación Hospital Universitario La Paz - IdiPAZ, Madrid, Spain
| | - Carlota Largo
- Departamento de Cirugía Experimental, Instituto de Investigación Hospital Universitario La Paz - IdiPAZ, Madrid, Spain
| | - Mario Vallejo
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (Ciberdem), Instituto de Salud Carlos III, Madrid, Spain
| | | | - Sebastián Cerdán
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain
| |
Collapse
|
76
|
Tebbenkamp ATN, Varela L, Choi J, Paredes MI, Giani AM, Song JE, Sestan-Pesa M, Franjic D, Sousa AMM, Liu ZW, Li M, Bichsel C, Koch M, Szigeti-Buck K, Liu F, Li Z, Kawasawa YI, Paspalas CD, Mineur YS, Prontera P, Merla G, Picciotto MR, Arnsten AFT, Horvath TL, Sestan N. The 7q11.23 Protein DNAJC30 Interacts with ATP Synthase and Links Mitochondria to Brain Development. Cell 2019; 175:1088-1104.e23. [PMID: 30318146 DOI: 10.1016/j.cell.2018.09.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/01/2018] [Accepted: 09/10/2018] [Indexed: 12/24/2022]
Abstract
Despite the known causality of copy-number variations (CNVs) to human neurodevelopmental disorders, the mechanisms behind each gene's contribution to the constellation of neural phenotypes remain elusive. Here, we investigated the 7q11.23 CNV, whose hemideletion causes Williams syndrome (WS), and uncovered that mitochondrial dysfunction participates in WS pathogenesis. Dysfunction is facilitated in part by the 7q11.23 protein DNAJC30, which interacts with mitochondrial ATP-synthase machinery. Removal of Dnajc30 in mice resulted in hypofunctional mitochondria, diminished morphological features of neocortical pyramidal neurons, and altered behaviors reminiscent of WS. The mitochondrial features are consistent with our observations of decreased integrity of oxidative phosphorylation supercomplexes and ATP-synthase dimers in WS. Thus, we identify DNAJC30 as an auxiliary component of ATP-synthase machinery and reveal mitochondrial maladies as underlying certain defects in brain development and function associated with WS.
Collapse
Affiliation(s)
- Andrew T N Tebbenkamp
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Luis Varela
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Jinmyung Choi
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Miguel I Paredes
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Alice M Giani
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Jae Eun Song
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Matija Sestan-Pesa
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Daniel Franjic
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - André M M Sousa
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Zhong-Wu Liu
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Mingfeng Li
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Candace Bichsel
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Marco Koch
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Klara Szigeti-Buck
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Fuchen Liu
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Zhuo Li
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yuka I Kawasawa
- Institute for Personalized Medicine and Departments of Biochemistry and Molecular Biology and Pharmacology, Penn State College of Medicine, Hershey, PA 17033, USA
| | - Constantinos D Paspalas
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yann S Mineur
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA
| | - Paolo Prontera
- Medical Genetics Unit, Hospital "Santa Maria della Misericordia," 06129 Perugia, Italy
| | - Giuseppe Merla
- Division of Medical Genetics, IRCCS Casa Sollievo della Sofferenza Hospital, 71013 San Giovanni Rotondo, Foggia, Italy
| | - Marina R Picciotto
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA
| | - Amy F T Arnsten
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA
| | - Tamas L Horvath
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Anatomy and Histology, University of Veterinary Medicine, 1078 Budapest, Hungary
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Genetics and of Comparative Medicine, Program in Cellular Neuroscience, Neurodegeneration and Repair, and Yale Child Study Center, Yale School of Medicine, New Haven, CT 06510, USA.
| |
Collapse
|
77
|
Romanov RA, Alpár A, Hökfelt T, Harkany T. Unified Classification of Molecular, Network, and Endocrine Features of Hypothalamic Neurons. Annu Rev Neurosci 2019; 42:1-26. [DOI: 10.1146/annurev-neuro-070918-050414] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Peripheral endocrine output relies on either direct or feed-forward multi-order command from the hypothalamus. Efficient coding of endocrine responses is made possible by the many neuronal cell types that coexist in intercalated hypothalamic nuclei and communicate through extensive synaptic connectivity. Although general anatomical and neurochemical features of hypothalamic neurons were described during the past decades, they have yet to be reconciled with recently discovered molecular classifiers and neurogenetic function determination. By interrogating magnocellular as well as parvocellular dopamine, GABA, glutamate, and phenotypically mixed neurons, we integrate available information at the molecular, cellular, network, and endocrine output levels to propose a framework for the comprehensive classification of hypothalamic neurons. Simultaneously, we single out putative neuronal subclasses for which future research can fill in existing gaps of knowledge to rationalize cellular diversity through function-determinant molecular marks in the hypothalamus.
Collapse
Affiliation(s)
- Roman A. Romanov
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, 1090 Vienna, Austria
| | - Alán Alpár
- Department of Anatomy, Histology, and Embryology, and SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Semmelweis University, H-1085 Budapest, Hungary
| | - Tomas Hökfelt
- Department of Neuroscience, Biomedicum, Karolinska Institutet, SE-17165 Stockholm, Sweden
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, 1090 Vienna, Austria
- Department of Neuroscience, Biomedicum, Karolinska Institutet, SE-17165 Stockholm, Sweden
| |
Collapse
|
78
|
Stanley S, Moheet A, Seaquist ER. Central Mechanisms of Glucose Sensing and Counterregulation in Defense of Hypoglycemia. Endocr Rev 2019; 40:768-788. [PMID: 30689785 PMCID: PMC6505456 DOI: 10.1210/er.2018-00226] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/17/2019] [Indexed: 12/12/2022]
Abstract
Glucose homeostasis requires an organism to rapidly respond to changes in plasma glucose concentrations. Iatrogenic hypoglycemia as a result of treatment with insulin or sulfonylureas is the most common cause of hypoglycemia in humans and is generally only seen in patients with diabetes who take these medications. The first response to a fall in glucose is the detection of impending hypoglycemia by hypoglycemia-detecting sensors, including glucose-sensing neurons in the hypothalamus and other regions. This detection is then linked to a series of neural and hormonal responses that serve to prevent the fall in blood glucose and restore euglycemia. In this review, we discuss the current state of knowledge about central glucose sensing and how detection of a fall in glucose leads to the stimulation of counterregulatory hormone and behavior responses. We also review how diabetes and recurrent hypoglycemia impact glucose sensing and counterregulation, leading to development of impaired awareness of hypoglycemia in diabetes.
Collapse
Affiliation(s)
- Sarah Stanley
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Amir Moheet
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Elizabeth R Seaquist
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, University of Minnesota, Minneapolis, Minnesota
| |
Collapse
|
79
|
Fuente-Martín E, Mellado-Gil JM, Cobo-Vuilleumier N, Martín-Montalvo A, Romero-Zerbo SY, Diaz Contreras I, Hmadcha A, Soria B, Martin Bermudo F, Reyes JC, Bermúdez-Silva FJ, Lorenzo PI, Gauthier BR. Dissecting the Brain/Islet Axis in Metabesity. Genes (Basel) 2019; 10:genes10050350. [PMID: 31072002 PMCID: PMC6562925 DOI: 10.3390/genes10050350] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/02/2019] [Accepted: 05/02/2019] [Indexed: 12/17/2022] Open
Abstract
The high prevalence of type 2 diabetes mellitus (T2DM), together with the fact that current treatments are only palliative and do not avoid major secondary complications, reveals the need for novel approaches to treat the cause of this disease. Efforts are currently underway to identify therapeutic targets implicated in either the regeneration or re-differentiation of a functional pancreatic islet β-cell mass to restore insulin levels and normoglycemia. However, T2DM is not only caused by failures in β-cells but also by dysfunctions in the central nervous system (CNS), especially in the hypothalamus and brainstem. Herein, we review the physiological contribution of hypothalamic neuronal and glial populations, particularly astrocytes, in the control of the systemic response that regulates blood glucose levels. The glucosensing capacity of hypothalamic astrocytes, together with their regulation by metabolic hormones, highlights the relevance of these cells in the control of glucose homeostasis. Moreover, the critical role of astrocytes in the response to inflammation, a process associated with obesity and T2DM, further emphasizes the importance of these cells as novel targets to stimulate the CNS in response to metabesity (over-nutrition-derived metabolic dysfunctions). We suggest that novel T2DM therapies should aim at stimulating the CNS astrocytic response, as well as recovering the functional pancreatic β-cell mass. Whether or not a common factor expressed in both cell types can be feasibly targeted is also discussed.
Collapse
Affiliation(s)
- Esther Fuente-Martín
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
| | - Jose M Mellado-Gil
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
| | - Nadia Cobo-Vuilleumier
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
| | - Alejandro Martín-Montalvo
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
| | - Silvana Y Romero-Zerbo
- Instituto de Investigación Biomédica de Málaga-IBIMA, UGC Endocrinología y Nutrición. Hospital Regional Universitario de Málaga, 29009 Málaga, Spain.
| | - Irene Diaz Contreras
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.
| | - Abdelkrim Hmadcha
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.
| | - Bernat Soria
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.
| | - Francisco Martin Bermudo
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.
| | - Jose C Reyes
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
| | - Francisco J Bermúdez-Silva
- Instituto de Investigación Biomédica de Málaga-IBIMA, UGC Endocrinología y Nutrición. Hospital Regional Universitario de Málaga, 29009 Málaga, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.
| | - Petra I Lorenzo
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
| | - Benoit R Gauthier
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucia-University of Pablo de Olavide-University of Seville-CSIC, 41092 Seville, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.
| |
Collapse
|
80
|
Baldini G, Phelan KD. The melanocortin pathway and control of appetite-progress and therapeutic implications. J Endocrinol 2019; 241:R1-R33. [PMID: 30812013 PMCID: PMC6500576 DOI: 10.1530/joe-18-0596] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 01/22/2019] [Indexed: 12/19/2022]
Abstract
The initial discovery that ob/ob mice become obese because of a recessive mutation of the leptin gene has been crucial to discover the melanocortin pathway to control appetite. In the melanocortin pathway, the fed state is signaled by abundance of circulating hormones such as leptin and insulin, which bind to receptors expressed at the surface of pro-opiomelanocortin (POMC) neurons to promote processing of POMC to the mature hormone α-melanocyte-stimulating hormone (α-MSH). The α-MSH released by POMC neurons then signals to decrease energy intake by binding to melanocortin-4 receptor (MC4R) expressed by MC4R neurons to the paraventricular nucleus (PVN). Conversely, in the 'starved state' activity of agouti-related neuropeptide (AgRP) and of neuropeptide Y (NPY)-expressing neurons is increased by decreased levels of circulating leptin and insulin and by the orexigenic hormone ghrelin to promote food intake. This initial understanding of the melanocortin pathway has recently been implemented by the description of the complex neuronal circuit that controls the activity of POMC, AgRP/NPY and MC4R neurons and downstream signaling by these neurons. This review summarizes the progress done on the melanocortin pathway and describes how obesity alters this pathway to disrupt energy homeostasis. We also describe progress on how leptin and insulin receptors signal in POMC neurons, how MC4R signals and how altered expression and traffic of MC4R change the acute signaling and desensitization properties of the receptor. We also describe how the discovery of the melanocortin pathway has led to the use of melanocortin agonists to treat obesity derived from genetic disorders.
Collapse
Affiliation(s)
- Giulia Baldini
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Kevin D. Phelan
- Department of Neurobiology & Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| |
Collapse
|
81
|
de Oliveira Bristot VJ, de Bem Alves AC, Cardoso LR, da Luz Scheffer D, Aguiar AS. The Role of PGC-1α/UCP2 Signaling in the Beneficial Effects of Physical Exercise on the Brain. Front Neurosci 2019; 13:292. [PMID: 30983964 PMCID: PMC6449457 DOI: 10.3389/fnins.2019.00292] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 03/13/2019] [Indexed: 01/12/2023] Open
Abstract
In understanding the pathology of neurological diseases, the role played by brain energy metabolism is gaining prominence. Animal models have demonstrated that regular physical exercise improves brain energy metabolism while also providing antidepressant, anxiolytic, antioxidant and neuroprotective functions. This review summarizes the latest evidence on the roles played by peroxisome proliferator-activated receptor gamma (PPAR-γ) coactivator 1-alpha (PGC-1α) and mitochondrial uncoupling protein (UCP) in this scenario. The beneficial effects of exercise seem to depend on crosstalk between muscles and nervous tissue through the increased release of muscle irisin during exercise.
Collapse
Affiliation(s)
- Viviane José de Oliveira Bristot
- Research Group on Biology of Exercise, Department of Health Sciences, Centro Araranguá, Federal University of Santa Catarina, Araranguá, Brazil
| | - Ana Cristina de Bem Alves
- Research Group on Biology of Exercise, Department of Health Sciences, Centro Araranguá, Federal University of Santa Catarina, Araranguá, Brazil
- Laboratório de Bioenergética e Estresse Oxidativo, Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Liziane Rosa Cardoso
- Research Group on Biology of Exercise, Department of Health Sciences, Centro Araranguá, Federal University of Santa Catarina, Araranguá, Brazil
| | - Débora da Luz Scheffer
- Research Group on Biology of Exercise, Department of Health Sciences, Centro Araranguá, Federal University of Santa Catarina, Araranguá, Brazil
- Laboratório de Bioenergética e Estresse Oxidativo, Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Aderbal Silva Aguiar
- Research Group on Biology of Exercise, Department of Health Sciences, Centro Araranguá, Federal University of Santa Catarina, Araranguá, Brazil
- Laboratório de Bioenergética e Estresse Oxidativo, Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| |
Collapse
|
82
|
Hass DT, Barnstable CJ. Cell Autonomous Neuroprotection by the Mitochondrial Uncoupling Protein 2 in a Mouse Model of Glaucoma. Front Neurosci 2019; 13:201. [PMID: 30906248 PMCID: PMC6418046 DOI: 10.3389/fnins.2019.00201] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 02/20/2019] [Indexed: 12/20/2022] Open
Abstract
Glaucoma is a group of disorders associated with retinal ganglion cell (RGC) degeneration and death. There is a clear contribution of mitochondrial dysfunction and oxidative stress toward glaucomatous RGC death. Mitochondrial uncoupling protein 2 (Ucp2) is a well-known regulator of oxidative stress that increases cell survival in acute models of oxidative damage. The impact of Ucp2 on cell survival during sub-acute and chronic neurodegenerative conditions, however, is not yet clear. Herein, we test the hypothesis that increased Ucp2 expression will improve RGC survival in a mouse model of glaucoma. We show that increasing RGC but not glial Ucp2 expression in transgenic animals decreases glaucomatous RGC death, but also that the PPAR-γ agonist rosiglitazone (RSG), an endogenous transcriptional activator of Ucp2, does not significantly alter RGC loss during glaucoma. Together, these data support a model whereby increased Ucp2 expression mediates neuroprotection during a long-term oxidative stressor, but that transcriptional activation alone is insufficient to elicit a neuroprotective effect, motivating further research in to the post-transcriptional regulation of Ucp2.
Collapse
Affiliation(s)
- Daniel T Hass
- Department of Neural and Behavioral Sciences, College of Medicine, The Pennsylvania State University, Hershey, PA, United States
| | - Colin J Barnstable
- Department of Neural and Behavioral Sciences, College of Medicine, The Pennsylvania State University, Hershey, PA, United States
| |
Collapse
|
83
|
Zhou P, Xie W, Meng X, Zhai Y, Dong X, Zhang X, Sun G, Sun X. Notoginsenoside R1 Ameliorates Diabetic Retinopathy through PINK1-Dependent Activation of Mitophagy. Cells 2019; 8:cells8030213. [PMID: 30832367 PMCID: PMC6468581 DOI: 10.3390/cells8030213] [Citation(s) in RCA: 91] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/23/2019] [Accepted: 02/26/2019] [Indexed: 01/09/2023] Open
Abstract
Accumulating evidence has indicated that inflammation, oxidative stress, apoptosis, and autophagy in retinal Müller cells are involved in diabetic retinopathy (DR). Notoginsenoside R1 (NGR1), a novel saponin extracted from Panax notoginseng, posesses pharmacological properties, including treating diabetic encephalopathy and improving microcirculatory disorders. Nevertheless, its beneficial effects on DR and the potential mechanism remain to be elucidated. In this study, we found retinal vascular degeneration, reduced retinal thickness, and impaired retinal function in db/db mice were all dramatically attenuated by oral treatment with NGR1 (30 mg/kg) for 12 weeks. NGR1 pretreatment also significantly inhibited apoptosis, markedly suppressed the VEGF expression, markedly increased PEDF expression and markedly inhibited oxidative stress and inflammation in rat retinal Müller cells (rMC-1) subjected to high glucose (HG) and in the retinas of db/db mice. Furthermore, NGR1 pre-treatment upregulated the level of PINK1 and Parkin, increased the LC3-II/LC3-I ratio, and downregulated the level of p62/SQSTM1 in rMC-1 cells induced by HG and in the retinas of db/db mice. Moreover, NGR1 administration enhanced the co-localization of GFP-LC3 puncta and MitoTracker in rMC-1 cells. Importantly, knockdown of PINK1 abolished the protective effects of NGR1. In conclusion, these phenomena suggested that NGR1 prevented DR via PINK1-dependent enhancement of mitophagy.
Collapse
Affiliation(s)
- Ping Zhou
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Weijie Xie
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Xiangbao Meng
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Yadong Zhai
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Xi Dong
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Xuelian Zhang
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Guibo Sun
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| | - Xiaobo Sun
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China.
- Key Laboratory of new drug discovery based on Classic Chinese medicine prescription, Chinese Academy of Medical Sciences, Beijing 100193, China.
| |
Collapse
|
84
|
Desmoulins L, Chrétien C, Paccoud R, Collins S, Cruciani-Guglielmacci C, Galinier A, Liénard F, Quinault A, Grall S, Allard C, Fenech C, Carneiro L, Mouillot T, Fournel A, Knauf C, Magnan C, Fioramonti X, Pénicaud L, Leloup C. Mitochondrial Dynamin-Related Protein 1 (DRP1) translocation in response to cerebral glucose is impaired in a rat model of early alteration in hypothalamic glucose sensing. Mol Metab 2019; 20:166-177. [PMID: 30553770 PMCID: PMC6358535 DOI: 10.1016/j.molmet.2018.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 11/19/2018] [Accepted: 11/22/2018] [Indexed: 02/08/2023] Open
Abstract
OBJECTIVE Hypothalamic glucose sensing (HGS) initiates insulin secretion (IS) via a vagal control, participating in energy homeostasis. This requires mitochondrial reactive oxygen species (mROS) signaling, dependent on mitochondrial fission, as shown by invalidation of the hypothalamic DRP1 protein. Here, our objectives were to determine whether a model with a HGS defect induced by a short, high fat-high sucrose (HFHS) diet in rats affected the fission machinery and mROS signaling within the mediobasal hypothalamus (MBH). METHODS Rats fed a HFHS diet for 3 weeks were compared with animals fed a normal chow. Both in vitro (calcium imaging) and in vivo (vagal nerve activity recordings) experiments to measure the electrical activity of isolated MBH gluco-sensitive neurons in response to increased glucose level were performed. In parallel, insulin secretion to a direct glucose stimulus in isolated islets vs. insulin secretion resulting from brain glucose stimulation was evaluated. Intra-carotid glucose load-induced hypothalamic DRP1 translocation to mitochondria and mROS (H2O2) production were assessed in both groups. Finally, compound C was intracerebroventricularly injected to block the proposed AMPK-inhibited DRP1 translocation in the MBH to reverse the phenotype of HFHS fed animals. RESULTS Rats fed a HFHS diet displayed a decreased HGS-induced IS. Responses of MBH neurons to glucose exhibited an alteration of their electrical activity, whereas glucose-induced insulin secretion in isolated islets was not affected. These MBH defects correlated with a decreased ROS signaling and glucose-induced translocation of the fission protein DRP1, as the vagal activity was altered. AMPK-induced inhibition of DRP1 translocation increased in this model, but its reversal through the injection of the compound C, an AMPK inhibitor, failed to restore HGS-induced IS. CONCLUSIONS A hypothalamic alteration of DRP1-induced fission and mROS signaling in response to glucose was observed in HGS-induced IS of rats exposed to a 3 week HFHS diet. Early hypothalamic modifications of the neuronal activity could participate in a primary defect of the control of IS and ultimately, the development of diabetes.
Collapse
Affiliation(s)
- Lucie Desmoulins
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Chloé Chrétien
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Romain Paccoud
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Stephan Collins
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Céline Cruciani-Guglielmacci
- CNRS UMR 8251, Unit of Functional and Adaptive Biology, Paris, France; Department of Physiology, Université Paris Diderot, Paris, France.
| | - Anne Galinier
- STROMALab, UMR CNRS 5273, EFS Pyrénées-Méditerranée, Université Paul Sabatier, Toulouse, France.
| | - Fabienne Liénard
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Aurore Quinault
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Sylvie Grall
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Camille Allard
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Claire Fenech
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Lionel Carneiro
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Thomas Mouillot
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France; Service d'Hépato-Gastroentérologie, hôpital du Bocage, Dijon, France.
| | - Audren Fournel
- Institut de Recherche en Santé Digestive, INSERM U1220, Université Paul Sabatier, Toulouse, France.
| | - Claude Knauf
- Institut de Recherche en Santé Digestive, INSERM U1220, Université Paul Sabatier, Toulouse, France.
| | - Christophe Magnan
- CNRS UMR 8251, Unit of Functional and Adaptive Biology, Paris, France.
| | - Xavier Fioramonti
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France; UMR 1286, NutriNeuro, INRA, Université de Bordeaux, Bordeaux INP, Bordeaux, France.
| | - Luc Pénicaud
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Corinne Leloup
- Centre des Sciences du Goût et de l'Alimentation, UMR CNRS 6265, INRA 1324, AgroSup, Univ. Bourgogne Franche-Comté, F-21000 Dijon, France.
| |
Collapse
|
85
|
Qin N, Cai T, Ke Q, Yuan Q, Luo J, Mao X, Jiang L, Cao H, Wen P, Zen K, Zhou Y, Yang J. UCP2-dependent improvement of mitochondrial dynamics protects against acute kidney injury. J Pathol 2018; 247:392-405. [PMID: 30426490 DOI: 10.1002/path.5198] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 10/11/2018] [Accepted: 11/06/2018] [Indexed: 01/06/2023]
Abstract
Acute kidney injury (AKI) is a public health concern, with high morbidity and mortality rates in hospitalized patients and because survivors have an increased risk of progression to chronic kidney disease. Mitochondrial damage is the critical driver of AKI-associated dysfunction and loss of tubular epithelial cells; however, the pathways that mediate these events are poorly defined. Here, in murine ischemia/reperfusion (I/R)-induced AKI, we determined that mitochondrial damage is associated with the level of renal uncoupling protein 2 (UCP2). In hypoxia-damaged proximal tubular cells, a disruption of mitochondrial dynamics demonstrated by mitochondrial fragmentation and disturbance between fusion and fission was clearly indicated. Ucp2-deficient mice (knockout mice) with I/R injury experienced more severe AKI and mitochondrial fragmentation than wild-type mice. Moreover, genetic or pharmacological treatment increased UCP2 expression, improved renal function, reduced tubular injury and limited mitochondrial fission. In cultured proximal tubular epithelial cells, hypoxia-induced mitochondrial fission was exacerbated in cells with UCP2 deletion, whereas an increase in UCP2 ameliorated the hypoxia-induced disturbance of the balance between mitochondrial fusion and fission. Furthermore, results following modulation of UCP2 suggested it has a role in preserving mitochondrial integrity by preventing loss of membrane potential and reducing subsequent mitophagy. Taken together, our results indicate that UCP2 is protective against AKI and suggest that enhancing UCP2 to improve mitochondrial dynamics has potential as a strategy for improving outcomes of renal injury. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Nan Qin
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Ting Cai
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Qingqing Ke
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Qi Yuan
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Jing Luo
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Xiaoming Mao
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Lei Jiang
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Hongdi Cao
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Ping Wen
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Ke Zen
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Advanced Institute of Life Sciences, Nanjing, PR China
| | - Yang Zhou
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| | - Junwei Yang
- Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, PR China
| |
Collapse
|
86
|
Geng T, Liu Y, Xu Y, Jiang Y, Zhang N, Wang Z, Carmichael GG, Taylor HS, Li D, Huang Y. H19 lncRNA Promotes Skeletal Muscle Insulin Sensitivity in Part by Targeting AMPK. Diabetes 2018; 67:2183-2198. [PMID: 30201684 PMCID: PMC6198334 DOI: 10.2337/db18-0370] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/24/2018] [Indexed: 12/12/2022]
Abstract
Skeletal muscle plays a pivotal role in regulating systemic glucose homeostasis in part through the conserved cellular energy sensor AMPK. AMPK activation increases glucose uptake, lipid oxidation, and mitochondrial biogenesis, leading to enhanced muscle insulin sensitivity and whole-body energy metabolism. Here we show that the muscle-enriched H19 long noncoding RNA (lncRNA) acts to enhance muscle insulin sensitivity, at least in part, by activating AMPK. We identify the atypical dual-specificity phosphatase DUSP27/DUPD1 as a potentially important downstream effector of H19. We show that DUSP27, which is highly expressed in muscle with previously unknown physiological function, interacts with and activates AMPK in muscle cells. Consistent with decreased H19 expression in the muscle of insulin-resistant human subjects and rodents, mice with genetic H19 ablation exhibit muscle insulin resistance. Furthermore, a high-fat diet downregulates muscle H19 via both posttranscriptional and epigenetic mechanisms. Our results uncover an evolutionarily conserved, highly expressed lncRNA as an important regulator of muscle insulin sensitivity.
Collapse
Affiliation(s)
- Tingting Geng
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
- Department of Endocrinology, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, People's Republic of China
| | - Ya Liu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
- Department of Veterinary Medicine, College of Animal Science and Technology, Anhui Agricultural University, Hefei, Anhui, People's Republic of China
| | - Yetao Xu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
- Department of Obstetrics and Gynecology, First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| | - Ying Jiang
- Department of Obstetrics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People's Republic of China
| | - Na Zhang
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, CT
| | - Zhangsheng Wang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
- Department of Cardiology, Fifth People's Hospital of Shanghai, Fudan University, Shanghai, People's Republic of China
| | - Gordon G Carmichael
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, CT
| | - Hugh S Taylor
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
| | - Da Li
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
- Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University, Shenyang, Liaoning, People's Republic of China
| | - Yingqun Huang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine, New Haven, CT
| |
Collapse
|
87
|
Jin S, Diano S. Mitochondrial Dynamics and Hypothalamic Regulation of Metabolism. Endocrinology 2018; 159:3596-3604. [PMID: 30203064 PMCID: PMC6157417 DOI: 10.1210/en.2018-00667] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 09/02/2018] [Indexed: 01/22/2023]
Abstract
Mitochondria are cellular organelles that play an important role in bioenergetic processes. In the central nervous system, high energy-demanding neurons are critically dependent on mitochondria to fulfill their appropriate functions. The hypothalamus is a key brain area for maintaining glucose and energy homeostasis via the ability of hypothalamic neurons to sense, integrate, and respond to numerous metabolic signals. Mitochondrial function has emerged as an important component in the regulation of hypothalamic neurons controlling glucose and energy homeostasis. Although the underlying mechanisms are not fully understood, emerging evidence indicates that mitochondrial dysfunction in hypothalamic neurons may contribute to the development of various metabolic diseases, including obesity and type 2 diabetes mellitus (T2DM). In this review, we summarize recent studies demonstrating the link between mitochondria and hypothalamic neural control of glucose and energy homeostasis. Finally, this review provides an insight to understand how mitochondria in hypothalamic neurons may contribute to the development of metabolic disorders, such as T2DM and obesity.
Collapse
Affiliation(s)
- Sungho Jin
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut
| | - Sabrina Diano
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut
- Department of Clinical Medicine and Surgery, University of Naples “Federico II,” Naples, Italy
| |
Collapse
|
88
|
Ježek P, Holendová B, Garlid KD, Jabůrek M. Mitochondrial Uncoupling Proteins: Subtle Regulators of Cellular Redox Signaling. Antioxid Redox Signal 2018; 29:667-714. [PMID: 29351723 PMCID: PMC6071544 DOI: 10.1089/ars.2017.7225] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
SIGNIFICANCE Mitochondria are the energetic, metabolic, redox, and information signaling centers of the cell. Substrate pressure, mitochondrial network dynamics, and cristae morphology state are integrated by the protonmotive force Δp or its potential component, ΔΨ, which are attenuated by proton backflux into the matrix, termed uncoupling. The mitochondrial uncoupling proteins (UCP1-5) play an eminent role in the regulation of each of the mentioned aspects, being involved in numerous physiological events including redox signaling. Recent Advances: UCP2 structure, including purine nucleotide and fatty acid (FA) binding sites, strongly support the FA cycling mechanism: UCP2 expels FA anions, whereas uncoupling is achieved by the membrane backflux of protonated FA. Nascent FAs, cleaved by phospholipases, are preferential. The resulting Δp dissipation decreases superoxide formation dependent on Δp. UCP-mediated antioxidant protection and its impairment are expected to play a major role in cell physiology and pathology. Moreover, UCP2-mediated aspartate, oxaloacetate, and malate antiport with phosphate is expected to alter metabolism of cancer cells. CRITICAL ISSUES A wide range of UCP antioxidant effects and participations in redox signaling have been reported; however, mechanisms of UCP activation are still debated. Switching off/on the UCP2 protonophoretic function might serve as redox signaling either by employing/releasing the extra capacity of cell antioxidant systems or by directly increasing/decreasing mitochondrial superoxide sources. Rapid UCP2 degradation, FA levels, elevation of purine nucleotides, decreased Mg2+, or increased pyruvate accumulation may initiate UCP-mediated redox signaling. FUTURE DIRECTIONS Issues such as UCP2 participation in glucose sensing, neuronal (synaptic) function, and immune cell activation should be elucidated. Antioxid. Redox Signal. 29, 667-714.
Collapse
Affiliation(s)
- Petr Ježek
- 1 Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences , Prague, Czech Republic
| | - Blanka Holendová
- 1 Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences , Prague, Czech Republic
| | - Keith D Garlid
- 2 UCLA Cardiovascular Research Laboratory, David Geffen School of Medicine at UCLA , Los Angeles, California
| | - Martin Jabůrek
- 1 Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences , Prague, Czech Republic
| |
Collapse
|
89
|
Tian XY, Ma S, Tse G, Wong WT, Huang Y. Uncoupling Protein 2 in Cardiovascular Health and Disease. Front Physiol 2018; 9:1060. [PMID: 30116205 PMCID: PMC6082951 DOI: 10.3389/fphys.2018.01060] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Accepted: 07/16/2018] [Indexed: 12/22/2022] Open
Abstract
Uncoupling protein 2 (UCP2) belongs to the family of mitochondrial anion carrier proteins. It uncouples oxygen consumption from ATP synthesis. UCP2 is ubiquitously expressed in most cell types to reduce oxidative stress. It is tightly regulated at the transcriptional, translational, and post-translational levels. UCP2 in the cardiovascular system is being increasingly recognized as an important molecule to defend against various stress signals such as oxidative stress in the pathology of vascular dysfunction, atherosclerosis, hypertension, and cardiac injuries. UCP2 protects against cellular dysfunction through reducing mitochondrial oxidative stress and modulation of mitochondrial function. In view of the different functions of UCP2 in various cell types that contribute to whole body homeostasis, cell type-specific modification of UCP2 expression may offer a better approach to help understanding how UCP2 governs mitochondrial function, reactive oxygen species production and transmembrane proton leak and how dysfunction of UCP2 participates in the development of cardiovascular diseases. This review article provided an update on the physiological regulation of UCP2 in the cardiovascular system, and also discussed the involvement of UCP2 deficiency and associated oxidative stress in the pathogenesis of several common cardiovascular diseases. Drugs targeting UCP2 expression and activity might serve another effective strategy to ameliorate cardiovascular dysfunction. However, more detailed mechanistic study will be needed to dissect the role of UCP2, the regulation of UCP2 expression, and the cellular responses to the changes of UCP2 expression in normal and stressed situations at different stages of cardiovascular diseases.
Collapse
Affiliation(s)
- Xiao Yu Tian
- School of Biomedical Sciences, Institute of Vascular Medicine, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Shuangtao Ma
- Division of Nanomedicine and Molecular Intervention, Department of Medicine, Michigan State University, East Lansing, MI, United States
| | - Gary Tse
- Department of Medicine and Therapeutics, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Wing Tak Wong
- School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Yu Huang
- School of Biomedical Sciences, Institute of Vascular Medicine, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China
| |
Collapse
|
90
|
FOXO1 inhibition potentiates endothelial angiogenic functions in diabetes via suppression of ROCK1/Drp1-mediated mitochondrial fission. Biochim Biophys Acta Mol Basis Dis 2018; 1864:2481-2494. [DOI: 10.1016/j.bbadis.2018.04.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Revised: 03/30/2018] [Accepted: 04/08/2018] [Indexed: 12/22/2022]
|
91
|
|
92
|
Zhang N, Geng T, Wang Z, Zhang R, Cao T, Camporez JP, Cai SY, Liu Y, Dandolo L, Shulman GI, Carmichael GG, Taylor HS, Huang Y. Elevated hepatic expression of H19 long noncoding RNA contributes to diabetic hyperglycemia. JCI Insight 2018; 3:120304. [PMID: 29769440 DOI: 10.1172/jci.insight.120304] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/19/2018] [Indexed: 11/17/2022] Open
Abstract
Excessive hepatic glucose production (HGP) contributes significantly to the hyperglycemia of type 2 diabetes; however, the molecular mechanism underlying this dysregulation remains poorly understood. Here, we show that fasting temporally increases the expression of H19 long noncoding RNA (lncRNA) in nondiabetic mouse liver, whereas its level is chronically elevated in diet-induced diabetic mice, consistent with the previously reported chronic hepatic H19 increase in diabetic patients. Importantly, liver-specific H19 overexpression promotes HGP, hyperglycemia, and insulin resistance, while H19 depletion enhances insulin-dependent suppression of HGP. Using genome-wide methylation and transcriptome analyses, we demonstrate that H19 knockdown in hepatic cells alters promoter methylation and expression of Hnf4a, a master gluconeogenic transcription factor, and that this regulation is recapitulated in vivo. Our findings offer a mechanistic explanation of lncRNA H19's role in the pathogenesis of diabetic hyperglycemia and suggest that targeting hepatic H19 may hold the potential of new treatment for this disease.
Collapse
Affiliation(s)
- Na Zhang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Tingting Geng
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Endocrinology, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, China
| | - Zhangsheng Wang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Cardiology, Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Ruling Zhang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Tiefeng Cao
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Gynecology and Obstetrics, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Joao Paulo Camporez
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Shi-Ying Cai
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Ya Liu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Veterinary Medicine, College of Animal Science and Technology, Anhui Agricultural University, Hefei, Anhui, China
| | - Luisa Dandolo
- Department of Genetics and Development, Inserm U1016, Institut Cochin, Paris, France
| | - Gerald I Shulman
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Gordon G Carmichael
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Hugh S Taylor
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Yingqun Huang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA
| |
Collapse
|
93
|
Li N, Wang H, Jiang C, Zhang M. Renal ischemia/reperfusion-induced mitophagy protects against renal dysfunction via Drp1-dependent-pathway. Exp Cell Res 2018; 369:27-33. [PMID: 29704468 DOI: 10.1016/j.yexcr.2018.04.025] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 03/24/2018] [Accepted: 04/24/2018] [Indexed: 11/16/2022]
Abstract
Autophagy is upregulated under stress conditions to degrade superfluous proteins and recycle damaged organelles including damaged mitochondria. However, the occurrence of mitochondrial autophagy and its contribution remain to be elucidated during renal ischemia/reperfusion injury (IRI). In this study, mitophagosomes and engulfed mitochondria were frequently observed by electron microscopy after renal IRI vs. control. Meanwhile, the increase of lipidated microtubule associated protein light chain 3 (LC3-II) and decrease of mitochondrial proteins were detected by western blot, suggesting the presence of mitophagy. Drp1 translocated to mitochondria and was phosphorylated at S616 in response to IRI. Interestingly, we found that inhibiting drp1 phosphorylation with mdivi-1 significantly suppressed IRI-induced mitophagy without affecting general autophagy. Furthermore, our results showed that downregulation of mitophagy significantly exacerbated cell apoptosis and markedly aggravated kidney dysfunction induced by IRI. Taken together, these data indicate that mitophagy was activated via Drp1-dependent pathway and such mitophagic clearance of damaged mitochondria protects cells from IRI-induced apoptosis.
Collapse
Affiliation(s)
- Nan Li
- Department of Nephrology, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Hengjin Wang
- Department of Nephrology, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China.
| | - Chunming Jiang
- Department of Nephrology, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China.
| | - Miao Zhang
- Department of Nephrology, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China.
| |
Collapse
|
94
|
Abstract
Reactive oxygen species (ROS) are well known for their role in mediating both physiological and pathophysiological signal transduction. Enzymes and subcellular compartments that typically produce ROS are associated with metabolic regulation, and diseases associated with metabolic dysfunction may be influenced by changes in redox balance. In this review, we summarize the current literature surrounding ROS and their role in metabolic and inflammatory regulation, focusing on ROS signal transduction and its relationship to disease progression. In particular, we examine ROS production in compartments such as the cytoplasm, mitochondria, peroxisome, and endoplasmic reticulum and discuss how ROS influence metabolic processes such as proteasome function, autophagy, and general inflammatory signaling. We also summarize and highlight the role of ROS in the regulation metabolic/inflammatory diseases including atherosclerosis, diabetes mellitus, and stroke. In order to develop therapies that target oxidative signaling, it is vital to understand the balance ROS signaling plays in both physiology and pathophysiology, and how manipulation of this balance and the identity of the ROS may influence cellular and tissue homeostasis. An increased understanding of specific sources of ROS production and an appreciation for how ROS influence cellular metabolism may help guide us in the effort to treat cardiovascular diseases.
Collapse
Affiliation(s)
- Steven J Forrester
- From the Division of Cardiology, Department of Medicine, Emory University, Atlanta GA
| | - Daniel S Kikuchi
- From the Division of Cardiology, Department of Medicine, Emory University, Atlanta GA
| | - Marina S Hernandes
- From the Division of Cardiology, Department of Medicine, Emory University, Atlanta GA
| | - Qian Xu
- From the Division of Cardiology, Department of Medicine, Emory University, Atlanta GA
| | - Kathy K Griendling
- From the Division of Cardiology, Department of Medicine, Emory University, Atlanta GA.
| |
Collapse
|
95
|
Zhou C, Teegala SB, Khan BA, Gonzalez C, Routh VH. Hypoglycemia: Role of Hypothalamic Glucose-Inhibited (GI) Neurons in Detection and Correction. Front Physiol 2018; 9:192. [PMID: 29593556 PMCID: PMC5854653 DOI: 10.3389/fphys.2018.00192] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 02/23/2018] [Indexed: 01/08/2023] Open
Abstract
Hypoglycemia is a profound threat to the brain since glucose is its primary fuel. As a result, glucose sensors are widely located in the central nervous system and periphery. In this perspective we will focus on the role of hypothalamic glucose-inhibited (GI) neurons in sensing and correcting hypoglycemia. In particular, we will discuss GI neurons in the ventromedial hypothalamus (VMH) which express neuronal nitric oxide synthase (nNOS) and in the perifornical hypothalamus (PFH) which express orexin. The ability of VMH nNOS-GI neurons to depolarize in low glucose closely parallels the hormonal response to hypoglycemia which stimulates gluconeogenesis. We have found that nitric oxide (NO) production in low glucose is dependent on oxidative status. In this perspective we will discuss the potential relevance of our work showing that enhancing the glutathione antioxidant system prevents hypoglycemia associated autonomic failure (HAAF) in non-diabetic rats whereas VMH overexpression of the thioredoxin antioxidant system restores hypoglycemia counterregulation in rats with type 1 diabetes.We will also address the potential role of the orexin-GI neurons in the arousal response needed for hypoglycemia awareness which leads to behavioral correction (e.g., food intake, glucose administration). The potential relationship between the hypothalamic sensors and the neurocircuitry in the hindbrain and portal mesenteric vein which is critical for hypoglycemia correction will then be discussed.
Collapse
Affiliation(s)
| | | | | | | | - Vanessa H. Routh
- Department of Pharmacology, Physiology and Neurosciences, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
| |
Collapse
|
96
|
Lima AR, Santos L, Correia M, Soares P, Sobrinho-Simões M, Melo M, Máximo V. Dynamin-Related Protein 1 at the Crossroads of Cancer. Genes (Basel) 2018; 9:genes9020115. [PMID: 29466320 PMCID: PMC5852611 DOI: 10.3390/genes9020115] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 02/13/2018] [Accepted: 02/13/2018] [Indexed: 12/13/2022] Open
Abstract
Mitochondrial dynamics are known to have an important role in so-called age-related diseases, including cancer. Mitochondria is an organelle involved in many key cellular functions and responds to physiologic or stress stimuli by adapting its structure and function. Perhaps the most important structural changes involve mitochondrial dynamics (fission and fusion), which occur in normal cells as well as in cells under dysregulation, such as cancer cells. Dynamin-related protein 1 (DRP1), a member of the dynamin family of guanosine triphosphatases (GTPases), is the key component of mitochondrial fission machinery. Dynamin-related protein 1 is associated with different cell processes such as apoptosis, mitochondrial biogenesis, mitophagy, metabolism, and cell proliferation, differentiation, and transformation. The role of DRP1 in tumorigenesis may seem to be paradoxical, since mitochondrial fission is a key mediator of two very different processes, cellular apoptosis and cell mitosis. Dynamin-related protein 1 has been associated with the development of distinct human cancers, including changes in mitochondrial energetics and cellular metabolism, cell proliferation, and stem cell maintenance, invasion, and promotion of metastases. However, the underlying mechanism for this association is still being explored. Herein, we review the published knowledge on the role of DRP1 in cancer, exploring its interaction with different biological processes in the tumorigenesis context.
Collapse
Affiliation(s)
- Ana Rita Lima
- Medical Faculty of University of Porto-FMUP, Porto 4200-135, Portugal.
| | - Liliana Santos
- Cancer Signaling & Metabolism Group, Instituto de Investigação e Inovação em Saúde (Institute for Research and Innovation in Health Sciences) (I3S), University of Porto, Porto 4200-135, Portugal.
- Cancer Signaling & Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto 4200-135, Portugal.
- Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto, Porto 4200-135, Portugal.
| | - Marcelo Correia
- Cancer Signaling & Metabolism Group, Instituto de Investigação e Inovação em Saúde (Institute for Research and Innovation in Health Sciences) (I3S), University of Porto, Porto 4200-135, Portugal.
- Cancer Signaling & Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto 4200-135, Portugal.
| | - Paula Soares
- Cancer Signaling & Metabolism Group, Instituto de Investigação e Inovação em Saúde (Institute for Research and Innovation in Health Sciences) (I3S), University of Porto, Porto 4200-135, Portugal.
- Cancer Signaling & Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto 4200-135, Portugal.
- Department of Pathology, Medical Faculty of University of Porto (FMUP), Porto 4200-135, Portugal.
| | - Manuel Sobrinho-Simões
- Cancer Signaling & Metabolism Group, Instituto de Investigação e Inovação em Saúde (Institute for Research and Innovation in Health Sciences) (I3S), University of Porto, Porto 4200-135, Portugal.
- Cancer Signaling & Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto 4200-135, Portugal.
- Department of Pathology, Medical Faculty of University of Porto (FMUP), Porto 4200-135, Portugal.
- Department of Pathology and Oncology, Centro Hospitalar São João, Porto 4200-135, Portugal.
| | - Miguel Melo
- Cancer Signaling & Metabolism Group, Instituto de Investigação e Inovação em Saúde (Institute for Research and Innovation in Health Sciences) (I3S), University of Porto, Porto 4200-135, Portugal.
- Cancer Signaling & Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto 4200-135, Portugal.
- Department of Endocrinology, Diabetes and Metabolism, Centro Hospitalar e Universitário de Coimbra (Coimbra University Hospital Centre), Coimbra 3000-075, Portugal.
- Faculty of Medicine, University of Coimbra, Coimbra 3000-548, Portugal.
| | - Valdemar Máximo
- Cancer Signaling & Metabolism Group, Instituto de Investigação e Inovação em Saúde (Institute for Research and Innovation in Health Sciences) (I3S), University of Porto, Porto 4200-135, Portugal.
- Cancer Signaling & Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto 4200-135, Portugal.
- Department of Pathology, Medical Faculty of University of Porto (FMUP), Porto 4200-135, Portugal.
| |
Collapse
|
97
|
Cunarro J, Casado S, Lugilde J, Tovar S. Hypothalamic Mitochondrial Dysfunction as a Target in Obesity and Metabolic Disease. Front Endocrinol (Lausanne) 2018; 9:283. [PMID: 29904371 PMCID: PMC5990598 DOI: 10.3389/fendo.2018.00283] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 05/14/2018] [Indexed: 01/06/2023] Open
Abstract
Mitochondria are important organelles for the adaptation to energy demand that play a central role in bioenergetics metabolism. The mitochondrial architecture and mitochondrial machinery exhibits a high degree of adaptation in relation to nutrient availability. On the other hand, its disruption markedly affects energy homeostasis. The brain, more specifically the hypothalamus, is the main hub that controls energy homeostasis. Nevertheless, until now, almost all studies in relation to mitochondrial dysfunction and energy metabolism have focused in peripheral tissues like brown adipose tissue, muscle, and pancreas. In this review, we highlight the relevance of the hypothalamus and the influence on mitochondrial machinery in its function as well as its consequences in terms of alterations in both energy and metabolic homeostasis.
Collapse
Affiliation(s)
- Juan Cunarro
- Departamento de Fisioloxía and Centro de Investigación en Medicina Molecular (CIMUS), Universidade de Santiago de Compostela, Instituto de Investigaciones Sanitarias de Santiago de Compostela (IDIS), Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Madrid, Spain
| | - Sabela Casado
- Departamento de Fisioloxía and Centro de Investigación en Medicina Molecular (CIMUS), Universidade de Santiago de Compostela, Instituto de Investigaciones Sanitarias de Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Javier Lugilde
- Departamento de Fisioloxía and Centro de Investigación en Medicina Molecular (CIMUS), Universidade de Santiago de Compostela, Instituto de Investigaciones Sanitarias de Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Sulay Tovar
- Departamento de Fisioloxía and Centro de Investigación en Medicina Molecular (CIMUS), Universidade de Santiago de Compostela, Instituto de Investigaciones Sanitarias de Santiago de Compostela (IDIS), Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Madrid, Spain
- *Correspondence: Sulay Tovar,
| |
Collapse
|
98
|
Fioramonti X, Chrétien C, Leloup C, Pénicaud L. Recent Advances in the Cellular and Molecular Mechanisms of Hypothalamic Neuronal Glucose Detection. Front Physiol 2017; 8:875. [PMID: 29184506 PMCID: PMC5694446 DOI: 10.3389/fphys.2017.00875] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 10/18/2017] [Indexed: 11/18/2022] Open
Abstract
The hypothalamus have been recognized for decades as one of the major brain centers for the control of energy homeostasis. This area contains specialized neurons able to detect changes in nutrients level. Among them, glucose-sensing neurons use glucose as a signaling molecule in addition to its fueling role. In this review we will describe the different sub-populations of glucose-sensing neurons present in the hypothalamus and highlight their nature in terms of neurotransmitter/neuropeptide expression. This review will particularly discuss whether pro-opiomelanocortin (POMC) neurons from the arcuate nucleus are directly glucose-sensing. In addition, recent observations in glucose-sensing suggest a subtle system with different mechanisms involved in the detection of changes in glucose level and their involvement in specific physiological functions. Several data point out the critical role of reactive oxygen species (ROS) and mitochondria dynamics in the detection of increased glucose. This review will also highlight that ATP-dependent potassium (KATP) channels are not the only channels mediating glucose-sensing and discuss the new role of transient receptor potential canonical channels (TRPC). We will discuss the recent advances in the determination of glucose-sensing machinery and propose potential line of research needed to further understand the regulation of brain glucose detection.
Collapse
Affiliation(s)
- Xavier Fioramonti
- NutriNeuro, Institut National de la Recherche Agronomique, Université de Bordeaux, Bordeaux, France.,Centre des Sciences du Goût et de l'Alimentation, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Bourgogne Franche-Comté, Dijon, France
| | - Chloé Chrétien
- Centre des Sciences du Goût et de l'Alimentation, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Bourgogne Franche-Comté, Dijon, France
| | - Corinne Leloup
- Centre des Sciences du Goût et de l'Alimentation, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Bourgogne Franche-Comté, Dijon, France
| | - Luc Pénicaud
- Centre des Sciences du Goût et de l'Alimentation, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Bourgogne Franche-Comté, Dijon, France.,Stromalab, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Université de Toulouse, Toulouse, France
| |
Collapse
|
99
|
Mitochondria-Bound Hexokinase (mt-HK) Activity Differ in Cortical and Hypothalamic Synaptosomes: Differential Role of mt-HK in H 2O 2 Depuration. Mol Neurobiol 2017; 55:5889-5900. [PMID: 29119535 DOI: 10.1007/s12035-017-0807-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 10/18/2017] [Indexed: 01/06/2023]
Abstract
Glucose and oxygen are vital for the brain, as these molecules provide energy and metabolic intermediates that are necessary for cell function. The glycolysis pathway and mitochondria play a pivotal role in cell energy metabolism, which is closely related to reactive oxygen species (ROS) production. Hexokinase (HK) is a key enzyme involved in glucose metabolism that modulates the level of brain mitochondrial ROS by recycling ADP for oxidative phosphorylation (OxPhos). Here, we hypothesize that the control of mitochondrial metabolism by hexokinase differs in distinct areas of the brain, such as the cortex and hypothalamus, in which ROS might function as signaling molecules. Thus, we investigated mitochondrial metabolism of synaptosomes derived from both brain regions. Cortical synaptosomes (CSy) show a predominance of glutamatergic synapses, while in the hypothalamic synaptosomes (HSy), the GABAergic synapses predominate. Significant differences of oxygen consumption and ROS production were related to higher mitochondrial complex II activity (succinate dehydrogenase-SDH) in CSy rather than to mitochondrial number. Mitochondrial HK (mt-HK) activity was higher in CSy than in HSy regardless the substrate added. Mitochondrial O2 consumption related to mt-HK activation by 2-deoxyglucose was also higher in CSy. In the presence of substrate for complex II, the activation of synaptosomal mt-HK promoted depuration of ROS in both HSy and CSy, while ROS depuration did not occur in HSy when substrate for complex I was used. The impact of the mt-HK inhibition by glucose-6-phosphate (G6P) was the same in synaptosomes from both areas. Together, the differences found between CSy and HSy indicate specific roles of mt-HK and SDH on the metabolism of each brain region, what probably depends on the main metabolic route that is used by the neurons.
Collapse
|
100
|
Abstract
A hypercaloric diet combined with a sedentary lifestyle is a major risk factor for the development of insulin resistance, type 2 diabetes mellitus (T2DM) and associated comorbidities. Standard treatment for T2DM begins with lifestyle modification, and includes oral medications and insulin therapy to compensate for progressive β-cell failure. However, current pharmaceutical options for T2DM are limited in that they do not maintain stable, durable glucose control without the need for treatment intensification. Furthermore, each medication is associated with adverse effects, which range from hypoglycaemia to weight gain or bone loss. Unexpectedly, fibroblast growth factor 1 (FGF1) and its low mitogenic variants have emerged as potentially safe candidates for restoring euglycaemia, without causing overt adverse effects. In particular, a single peripheral injection of FGF1 can lower glucose to normal levels within hours, without the risk of hypoglycaemia. Similarly, a single intracerebroventricular injection of FGF1 can induce long-lasting remission of the diabetic phenotype. This Review discusses potential mechanisms by which centrally administered FGF1 improves central glucose-sensing and peripheral glucose uptake in a sustained manner. Specifically, we explore the potential crosstalk between FGF1 and glucose-sensing neuronal circuits, hypothalamic neural stem cells and synaptic plasticity. Finally, we highlight therapeutic considerations of FGF1 and compare its metabolic actions with FGF15 (rodents), FGF19 (humans) and FGF21.
Collapse
Affiliation(s)
- Emanuel Gasser
- Gene Expression Laboratory, Salk Institute for Biological Studies
| | - Christopher P Moutos
- Gene Expression Laboratory, Salk Institute for Biological Studies
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
- College of Medicine, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, Arkansas 72205, USA
| | - Michael Downes
- Gene Expression Laboratory, Salk Institute for Biological Studies
| | - Ronald M Evans
- Gene Expression Laboratory, Salk Institute for Biological Studies
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| |
Collapse
|