1
|
Srour N, Caron A, Michael NJ. Do POMC neurons have a sweet tooth for leptin? Special issue: Role of nutrients in nervous control of energy balance. Biochimie 2024; 223:179-187. [PMID: 36122808 DOI: 10.1016/j.biochi.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/29/2022] [Accepted: 09/09/2022] [Indexed: 11/19/2022]
Abstract
Coordinated detection of changes in metabolic state by the nervous system is fundamental for survival. Hypothalamic pro-opiomelanocortin (POMC) neurons play a critical role in integrating metabolic signals, including leptin levels. They also coordinate adaptative responses and thus represent an important relay in the regulation of energy balance. Despite a plethora of work documenting the effects of individual hormones, nutrients, and neuropeptides on POMC neurons, the importance for crosstalk and additive effects between such signaling molecules is still underexplored. The ability of the metabolic state and the concentrations of nutrients, such as glucose, to influence leptin's effects on POMC neurons appears critical for understanding the function and complexity of this regulatory network. Here, we summarize the current knowledge on the effects of leptin on POMC neuron electrical excitability and discuss factors potentially contributing to variability in these effects, with a particular focus on the mouse models that have been developed and the importance of extracellular glucose levels. This review highlights the importance of the metabolic "environment" for determining hypothalamic neuronal responsiveness to metabolic cues and for determining the fundamental effects of leptin on the activity of hypothalamic POMC neurons.
Collapse
Affiliation(s)
- Nader Srour
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, 2725 chemin Sainte-Foy, Québec, QC, G1V 4G5, Canada; Faculté de Pharmacie, Université Laval, Québec, QC, Canada
| | - Alexandre Caron
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, 2725 chemin Sainte-Foy, Québec, QC, G1V 4G5, Canada; Faculté de Pharmacie, Université Laval, Québec, QC, Canada; Montreal Diabetes Research Center, QC, Canada.
| | - Natalie Jane Michael
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, 2725 chemin Sainte-Foy, Québec, QC, G1V 4G5, Canada; Faculté de Pharmacie, Université Laval, Québec, QC, Canada.
| |
Collapse
|
2
|
Gao Y, Wu Y, Tie F, Wang H. Stilbenoids from fenugreek seeds alleviate insulin resistance by regulating the PI3K/AKT/mTOR signaling pathway in a type 2 diabetes zebrafish model. Heliyon 2024; 10:e32007. [PMID: 39040253 PMCID: PMC11260975 DOI: 10.1016/j.heliyon.2024.e32007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/25/2024] [Accepted: 05/27/2024] [Indexed: 07/24/2024] Open
Abstract
Insulin resistance (IR) is the main cause of type 2 diabetes mellitus (T2DM). The specific targets and underlying mechanisms responsible for the ameliorative effects of the stilbenoid compounds found in fenugreek seeds for ameliorating IR require further study. Here, we were predicted by using the network pharmacology prediction, molecular docking and molecular dynamics simulation approach the targets in common and the potential mechanismsof three stilbenoid compounds (rhaponticin, desoxyrhaponticin, and rhapontigenin) in relation to T2DM and IR. The results showed that the compounds may improve IR through the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway. Molecular docking studies revealed that they exhibit high binding affinity with the structural domains of peroxisome proliferator-activated receptor gamma (PPARG), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), PI3K, and AKT. These results suggest that PPARG and GAPDH may be the potential targets for these three compounds in the treatment of T2DM.Subsequently, experiments using the zebrafish T2DM model showed that the stilbenoid compounds had varying degrees of efficacy in improving IR through the PI3K/AKT/mTOR signaling pathway, and rhaponticin had the most promising effects. The findings implicate a potential mechanism of action for the three stilbenoid compounds in enhancing insulin resistance (IR) through modulation of the PI3K/AKT/mTOR pathway.
Collapse
Affiliation(s)
- Yidan Gao
- Key Laboratory of Tibetan Medicine Research, Qinghai Provincial Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Science, Xining, 810008, PR China
| | - Yun Wu
- Key Laboratory of Tibetan Medicine Research, Qinghai Provincial Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Science, Xining, 810008, PR China
| | - Fangfang Tie
- Key Laboratory of Tibetan Medicine Research, Qinghai Provincial Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Science, Xining, 810008, PR China
| | - Honglun Wang
- Key Laboratory of Tibetan Medicine Research, Qinghai Provincial Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Science, Xining, 810008, PR China
| |
Collapse
|
3
|
Kelly MJ, Wagner EJ. Canonical transient receptor potential channels and hypothalamic control of homeostatic functions. J Neuroendocrinol 2024:e13392. [PMID: 38631680 DOI: 10.1111/jne.13392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/21/2024] [Accepted: 03/28/2024] [Indexed: 04/19/2024]
Abstract
Recent molecular biological and electrophysiological studies have identified multiple transient receptor potential (TRP) channels in hypothalamic neurons as critical modulators of homeostatic functions. In particular, the canonical transient receptor potential channels (TRPCs) are expressed in hypothalamic neurons that are vital for the control of fertility and energy homeostasis. Classical neurotransmitters such as serotonin and glutamate and peptide neurotransmitters such as kisspeptin, neurokinin B and pituitary adenylyl cyclase-activating polypeptide signal through their cognate G protein-coupled receptors to activate TPRC 4, 5 channels, which are essentially ligand-gated calcium channels. In addition to neurotransmitters, circulating hormones like insulin and leptin signal through insulin receptor (InsR) and leptin receptor (LRb), respectively, to activate TRPC 5 channels in hypothalamic arcuate nucleus pro-opiomelanocortin (POMC) and kisspeptin (arcuate Kiss1 [Kiss1ARH]) neurons to have profound physiological (excitatory) effects. Besides its overt depolarizing effects, TRPC channels conduct calcium ions into the cytoplasm, which has a plethora of downstream effects. Moreover, not only the expression of Trpc5 mRNA but also the coupling of receptors to TRPC 5 channel opening are regulated in different physiological states. In particular, the mRNA expression of Trpc5 is highly regulated in kisspeptin neurons by circulating estrogens, which ultimately dictates the firing pattern of kisspeptin neurons. In obesity states, InsRs are "uncoupled" from opening TRPC 5 channels in POMC neurons, rendering them less excitable. Therefore, in this review, we will focus on the critical role of TRPC 5 channels in regulating the excitability of Kiss1ARH and POMC neurons in different physiological and pathological states.
Collapse
Affiliation(s)
- Martin J Kelly
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon, USA
| | - Edward J Wagner
- Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Pomona, California, USA
| |
Collapse
|
4
|
Srour N, Lavoie O, Khouma A, Minbashi Moeini M, Plamondon J, Kinkead R, Michael NJ, Caron A. Electrophysiological Comparison of Definitive Pro-opiomelanocortin Neurons in the Arcuate Nucleus and the Retrochiasmatic Area of Male and Female Mice. Neuroscience 2023; 530:95-107. [PMID: 37619768 DOI: 10.1016/j.neuroscience.2023.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/28/2023] [Accepted: 08/16/2023] [Indexed: 08/26/2023]
Abstract
Pro-opiomelanocortin (POMC)-expressing neurons in the arcuate nucleus of the hypothalamus (ARC) are considered a major site of leptin action. Due to increasing evidence that POMC neurons are highly heterogeneous and indications that the conventional molecular tools to study their functions have important limitations, a reassessment of leptin's effects on definitive POMC neurons is needed. POMC neurons are also expressed in the retrochiasmatic area (RCA), where their function is poorly understood. Furthermore, the response of POMC neurons to leptin in females is largely unknown. Therefore, the present study aimed to determine the differences in leptin responsiveness of POMC neurons in the ARC and the RCA using a mouse model allowing adult-inducible fluorescent labeling. We performed whole-cell patch clamp electrophysiology on 154 POMC neurons from male and female mice. We confirmed and extended the model by which leptin depolarizes POMC neurons, in both the ARC and the RCA. Furthermore, we characterized the electrophysiological properties of an underappreciated subpopulation representing ∼10% of hypothalamic POMC neurons that are inhibited by leptin. We also provide evidence that sex does not appear to be a major determinant of basal properties and leptin responsiveness of POMC neurons, but that females are overall less responsive to leptin compared to males.
Collapse
Affiliation(s)
- Nader Srour
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada; Quebec Heart and Lung Institute, Quebec City, QC, Canada
| | - Olivier Lavoie
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada; Quebec Heart and Lung Institute, Quebec City, QC, Canada
| | - Axelle Khouma
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada; Quebec Heart and Lung Institute, Quebec City, QC, Canada
| | - Moein Minbashi Moeini
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada; Quebec Heart and Lung Institute, Quebec City, QC, Canada
| | | | - Richard Kinkead
- Quebec Heart and Lung Institute, Quebec City, QC, Canada; Faculty of Medicine, Université Laval, Quebec City, QC, Canada
| | - Natalie J Michael
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada; Quebec Heart and Lung Institute, Quebec City, QC, Canada.
| | - Alexandre Caron
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada; Quebec Heart and Lung Institute, Quebec City, QC, Canada.
| |
Collapse
|
5
|
de Souza GO, Teixeira PDS, Câmara NOS, Donato J. mTORC1 Signaling in AgRP Neurons Is Not Required to Induce Major Neuroendocrine Adaptations to Food Restriction. Cells 2023; 12:2442. [PMID: 37887286 PMCID: PMC10605346 DOI: 10.3390/cells12202442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/04/2023] [Accepted: 10/09/2023] [Indexed: 10/28/2023] Open
Abstract
Hypothalamic mTORC1 signaling is involved in nutrient sensing. Neurons that express the agouti-related protein (AgRP) are activated by food restriction and integrate interoceptive and exteroceptive signals to control food intake, energy expenditure, and other metabolic responses. To determine whether mTORC1 signaling in AgRP neurons is necessary for regulating energy and glucose homeostasis, especially in situations of negative energy balance, mice carrying ablation of the Raptor gene exclusively in AgRP-expressing cells were generated. AgRPΔRaptor mice showed no differences in body weight, fat mass, food intake, or energy expenditure; however, a slight improvement in glucose homeostasis was observed compared to the control group. When subjected to 5 days of food restriction (40% basal intake), AgRPΔRaptor female mice lost less lean body mass and showed a blunted reduction in energy expenditure, whereas AgRPΔRaptor male mice maintained a higher energy expenditure compared to control mice during the food restriction and 5 days of refeeding period. AgRPΔRaptor female mice did not exhibit the food restriction-induced increase in serum corticosterone levels. Finally, although hypothalamic fasting- or refeeding-induced Fos expression showed no differences between the groups, AgRPΔRaptor mice displayed increased hyperphagia during refeeding. Thus, some metabolic and neuroendocrine responses to food restriction are disturbed in AgRPΔRaptor mice.
Collapse
Affiliation(s)
- Gabriel O. de Souza
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (G.O.d.S.); (P.D.S.T.)
| | - Pryscila D. S. Teixeira
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (G.O.d.S.); (P.D.S.T.)
| | - Niels O. S. Câmara
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil;
| | - Jose Donato
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (G.O.d.S.); (P.D.S.T.)
| |
Collapse
|
6
|
Liu H, He Y, Bai J, Zhang C, Zhang F, Yang Y, Luo H, Yu M, Liu H, Tu L, Zhang N, Yin N, Han J, Yan Z, Scarcelli NA, Conde KM, Wang M, Bean JC, Potts CHS, Wang C, Hu F, Liu F, Xu Y. Hypothalamic Grb10 enhances leptin signalling and promotes weight loss. Nat Metab 2023; 5:147-164. [PMID: 36593271 DOI: 10.1038/s42255-022-00701-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 10/19/2022] [Indexed: 01/04/2023]
Abstract
Leptin acts on hypothalamic neurons expressing agouti-related protein (AgRP) or pro-opiomelanocortin (POMC) to suppress appetite and increase energy expenditure, but the intracellular mechanisms that modulate central leptin signalling are not fully understood. Here we show that growth factor receptor-bound protein 10 (Grb10), an adaptor protein that binds to the insulin receptor and negatively regulates its signalling pathway, can interact with the leptin receptor and enhance leptin signalling. Ablation of Grb10 in AgRP neurons promotes weight gain, while overexpression of Grb10 in AgRP neurons reduces body weight in male and female mice. In parallel, deletion or overexpression of Grb10 in POMC neurons exacerbates or attenuates diet-induced obesity, respectively. Consistent with its role in leptin signalling, Grb10 in AgRP and POMC neurons enhances the anorexic and weight-reducing actions of leptin. Grb10 also exaggerates the inhibitory effects of leptin on AgRP neurons via ATP-sensitive potassium channel-mediated currents while facilitating the excitatory drive of leptin on POMC neurons through transient receptor potential channels. Our study identifies Grb10 as a potent leptin sensitizer that contributes to the maintenance of energy homeostasis by enhancing the response of AgRP and POMC neurons to leptin.
Collapse
Affiliation(s)
- Hailan Liu
- National Clinical Research Center for Metabolic Diseases, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, China
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Yang He
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Juli Bai
- National Clinical Research Center for Metabolic Diseases, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, China
- Department of Cell Systems & Anatomy and Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Chuanhai Zhang
- Department of Cell Systems & Anatomy and Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Feng Zhang
- National Clinical Research Center for Metabolic Diseases, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Yongjie Yang
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Hairong Luo
- National Clinical Research Center for Metabolic Diseases, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Meng Yu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Hesong Liu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Longlong Tu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Nan Zhang
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Na Yin
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Junying Han
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Zili Yan
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Nikolas Anthony Scarcelli
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Kristine Marie Conde
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Mengjie Wang
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Jonathan Carter Bean
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Camille Hollan Sidell Potts
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Chunmei Wang
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Fang Hu
- National Clinical Research Center for Metabolic Diseases, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Feng Liu
- National Clinical Research Center for Metabolic Diseases, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, China.
| | - Yong Xu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA.
| |
Collapse
|
7
|
Qiu J, Bosch MA, Stincic TL, Hunker AC, Zweifel LS, Rønnekleiv OK, Kelly MJ. CRISPR/SaCas9 mutagenesis of stromal interaction molecule 1 in proopiomelanocortin neurons increases glutamatergic excitability and protects against diet-induced obesity. Mol Metab 2022; 66:101645. [PMID: 36442744 PMCID: PMC9727646 DOI: 10.1016/j.molmet.2022.101645] [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: 09/13/2022] [Revised: 11/09/2022] [Accepted: 11/22/2022] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE Proopiomelanocortin (POMC) neurons are the key anorexigenic hypothalamic neuron for integrating metabolic cues to generate the appropriate output for maintaining energy homeostasis and express the requisite channels as a perfect synaptic integrator in this role. Similar to the metabolic hormones leptin and insulin, glutamate also excites POMC neurons via group I metabotropic glutamate receptors (mGluR1 and 5, mGluR1/5) that activate Transient Receptor Potential Canonical (TRPC 5) Channels to cause depolarization. A key modulator of TRPC 5 channel activity is stromal interaction molecule 1 (STIM1), which is involved in recruitment of TRPC 5 channels from receptor-operated to store-operated calcium entry following depletion of calcium from the endoplasmic reticulum. METHODS We used a single adeno-associated viral (AAV) vector containing a recombinase-dependent Staphylococcus aureus Cas9 (SaCas) and a single guide RNA (sgRNA) to mutate Stim1 in POMCCre neurons in male mice, verified by qPCR of Stim1 mRNA expression in single POMC neurons. Whole-cell patch clamp experiments were conducted to validate the effects of Stim1 mutagenesis. Body weight and food intake were measured in male mice to assess disruptions in energy balance. RESULTS Reduced Stim1 expression augmented the efficacy of the mGluR1/5 agonist 3, 5-Dihydroxyphenylglycine (DHPG) to depolarize POMC neurons via a Gαq-coupled signaling pathway, which is an essential part of excitatory glutamatergic input in regulating energy homeostasis. The TRPC 5 channel blockers HC070 and Pico145 antagonized the excitatory effects of DHPG. As proof of principle, mutagenesis of Stim1 in POMC neurons reduced food intake, attenuated weight gain, reduced body fat and fat pad mass in mice fed a high fat diet. CONCLUSIONS Using CRISPR technology we have uncovered a critical role of STIM1 in modulating glutamatergic activation of TRPC 5 channels in POMC neurons, which ultimately is important for maintaining energy balance.
Collapse
Affiliation(s)
- Jian Qiu
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA,Corresponding author.Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Martha A. Bosch
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Todd L. Stincic
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Avery C. Hunker
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA
| | - Larry S. Zweifel
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA,Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Oline K. Rønnekleiv
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA,Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR 97006, USA
| | - Martin J. Kelly
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA,Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR 97006, USA,Corresponding author.Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| |
Collapse
|
8
|
Zakharova IO, Bayunova LV, Derkach KV, Ilyasov IO, Morina IY, Shpakov AO, Avrova NF. Effects of Intranasally Administered Insulin and Gangliosides on Hypothalamic Signaling and Expression of Hepatic Gluconeogenesis Genes in Rats with Type 2 Diabetes Mellitus. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022060072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
9
|
PI3K and AKT at the Interface of Signaling and Metabolism. Curr Top Microbiol Immunol 2022; 436:311-336. [DOI: 10.1007/978-3-031-06566-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
10
|
Cavalcanti-de-Albuquerque JP, Donato J. Rolling out physical exercise and energy homeostasis: Focus on hypothalamic circuitries. Front Neuroendocrinol 2021; 63:100944. [PMID: 34425188 DOI: 10.1016/j.yfrne.2021.100944] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/11/2021] [Accepted: 08/18/2021] [Indexed: 01/17/2023]
Abstract
Energy balance is the fine regulation of energy expenditure and energy intake. Negative energy balance causes body weight loss, while positive energy balance promotes weight gain. Modern societies offer a maladapted way of life, where easy access to palatable foods and the lack of opportunities to perform physical activity are considered the roots of the obesity pandemic. Physical exercise increases energy expenditure and, consequently, is supposed to promote weight loss. Paradoxically, physical exercise acutely drives anorexigenic-like effects, but the mechanisms are still poorly understood. Using an evolutionary background, this review aims to highlight the potential involvement of the melanocortin system and other hypothalamic neural circuitries regulating energy balance during and after physical exercise. The physiological significance of these changes will be explored, and possible signalling agents will be addressed. The knowledge discussed here might be important for clarifying obesity aetiology as well as new therapeutic approaches for body weight loss.
Collapse
Affiliation(s)
| | - José Donato
- Department of Physiology and Biophysics, University of São Paulo, São Paulo 05508-900, Brazil.
| |
Collapse
|
11
|
Cintas C, Douche T, Dantes Z, Mouton-Barbosa E, Bousquet MP, Cayron C, Therville N, Pont F, Ramos-Delgado F, Guyon C, Garmy-Susini B, Cappello P, Burlet-Schiltz O, Hirsch E, Gomez-Brouchet A, Thibault B, Reichert M, Guillermet-Guibert J. Phosphoproteomics Identifies PI3K Inhibitor-selective Adaptive Responses in Pancreatic Cancer Cell Therapy and Resistance. Mol Cancer Ther 2021; 20:2433-2445. [PMID: 34552006 DOI: 10.1158/1535-7163.mct-20-0981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 05/28/2021] [Accepted: 09/14/2021] [Indexed: 11/16/2022]
Abstract
The PI3K pathway is highly active in human cancers. The four class I isoforms of PI3K are activated by distinct mechanisms leading to a common downstream signaling. Their downstream redundancy is thought to be responsible for treatment failures of PI3K inhibitors. We challenged this concept, by mapping the differential phosphoproteome evolution in response to PI3K inhibitors with different isoform-selectivity patterns in pancreatic cancer, a disease currently without effective therapy. In this cancer, the PI3K signal was shown to control cell proliferation. We compared the effects of LY294002 that inhibit with equal potency all class I isoenzymes and downstream mTOR with the action of inhibitors with higher isoform selectivity toward PI3Kα, PI3Kβ, or PI3Kγ (namely, A66, TGX-221 and AS-252424). A bioinformatics global pathway analysis of phosphoproteomics data allowed us to identify common and specific signals activated by PI3K inhibitors supported by the biological data. AS-252424 was the most effective treatment and induced apoptotic pathway activation as well as the highest changes in global phosphorylation-regulated cell signal. However, AS-252424 treatment induced reactivation of Akt, therefore decreasing the treatment outcome on cell survival. Reversely, AS-252424 and A66 combination treatment prevented p-Akt reactivation and led to synergistic action in cell lines and patient organoids. The combination of clinically approved α-selective BYL-719 with γ-selective IPI-549 was more efficient than single-molecule treatment on xenograft growth. Mapping unique adaptive signaling responses to isoform-selective PI3K inhibition will help to design better combinative treatments that prevent the induction of selective compensatory signals.
Collapse
Affiliation(s)
- Célia Cintas
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | - Thibault Douche
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | - Zahra Dantes
- Klinik und Poliklinik für Innere Medizin II, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.,Center for Protein Assemblies (CPA), Technische Universität München, Garching, Germany.,German Cancer Consortium (DKTK), partner site Munich, Germany
| | - Emmanuelle Mouton-Barbosa
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS UMR 5089, UPS, Toulouse, France
| | - Marie-Pierre Bousquet
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS UMR 5089, UPS, Toulouse, France
| | - Coralie Cayron
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | - Nicole Therville
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | - Frédéric Pont
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France
| | - Fernanda Ramos-Delgado
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | - Camille Guyon
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | | | - Paola Cappello
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy.,Molecular Biotechnology Center (MBC), Turin, Italy
| | - Odile Burlet-Schiltz
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS UMR 5089, UPS, Toulouse, France
| | - Emilio Hirsch
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy.,Molecular Biotechnology Center (MBC), Turin, Italy
| | - Anne Gomez-Brouchet
- IUCT-O, Institut Claudius Regaud, Hopitaux de Toulouse, Biobank, Toulouse, France
| | - Benoît Thibault
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France.,Labex TouCAN, Toulouse, France
| | - Maximilian Reichert
- Klinik und Poliklinik für Innere Medizin II, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.,Center for Protein Assemblies (CPA), Technische Universität München, Garching, Germany.,German Cancer Consortium (DKTK), partner site Munich, Germany
| | - Julie Guillermet-Guibert
- INSERM, CNRS, Université Paul Sabatier, U1037, CRCT, Toulouse, France. .,Labex TouCAN, Toulouse, France
| |
Collapse
|
12
|
Multiple Leptin Signalling Pathways in the Control of Metabolism and Fertility: A Means to Different Ends? Int J Mol Sci 2021; 22:ijms22179210. [PMID: 34502119 PMCID: PMC8430761 DOI: 10.3390/ijms22179210] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/13/2021] [Accepted: 08/23/2021] [Indexed: 01/20/2023] Open
Abstract
The adipocyte-derived ‘satiety promoting’ hormone, leptin, has been identified as a key central regulator of body weight and fertility, such that its absence leads to obesity and infertility. Plasma leptin levels reflect body adiposity, and therefore act as an ‘adipostat’, whereby low leptin levels reflect a state of low body adiposity (under-nutrition/starvation) and elevated leptin levels reflect a state of high body adiposity (over-nutrition/obesity). While genetic leptin deficiency is rare, obesity-related leptin resistance is becoming increasingly common. In the absence of adequate leptin sensitivity, leptin is unable to exert its ‘anti-obesity’ effects, thereby exacerbating obesity. Furthermore, extreme leptin resistance and consequent low or absent leptin signalling resembles a state of starvation and can thus lead to infertility. However, leptin resistance occurs on a spectrum, and it is possible to be resistant to leptin’s metabolic effects while retaining leptin’s permissive effects on fertility. This may be because leptin exerts its modulatory effects on energy homeostasis and reproductive function through discrete intracellular signalling pathways, and these pathways are differentially affected by the molecules that promote leptin resistance. This review discusses the potential mechanisms that enable leptin to exert differential control over metabolic and reproductive function in the contexts of healthy leptin signalling and of diet-induced leptin resistance.
Collapse
|
13
|
Li Y, Wang X, Lu L, Wang M, Zhai Y, Tai X, Dilimulati D, Lei X, Xu J, Zhang C, Fu Y, Qu S, Li Q, Zhang C. Identification of novel GPCR partners of the central melanocortin signaling. Mol Metab 2021; 53:101317. [PMID: 34400348 PMCID: PMC8458986 DOI: 10.1016/j.molmet.2021.101317] [Citation(s) in RCA: 3] [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: 06/09/2021] [Revised: 08/03/2021] [Accepted: 08/10/2021] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVE Homo- or heterodimerization of G protein-coupled receptors (GPCRs) generally affects the normal functioning of these receptors and mediates the responses to a variety of physiological stimuli in vivo. It is well known that melanocortin-3 receptor (MC3R) and melanocortin-4 receptor (MC4R) are key regulators of appetite and energy homeostasis in the central nervous system. However, the GPCR partners of MC3R and MC4R are not well understood. Our objective is to analyze single cell RNA-seq datasets of the hypothalamus to explore and identify novel GPCR partners of MC3R and MC4R and examine the pharmacological effect on the downstream signal transduction and membrane translocation of melanocortin receptors. METHODS We conducted an integrative analysis of multiple single cell RNA-seq datasets to reveal the expression pattern and correlation of GPCR families in the mouse hypothalamus. The emerging GPCRs with important metabolic functions were selected for cloning and co-immunoprecipitation validation. The positive GPCR partners were then tested for the pharmacological activation, competitive binding assay and surface translocation ELISA experiments. RESULTS Based on the expression pattern of GPCRs and their function enrichment results, we narrowed down the range of potential GPCR interaction with MC3R and MC4R for further confirmation. Co-immunoprecipitation assay verified 23 and 32 novel GPCR partners that interacted with MC3R and MC4R in vitro. The presence of these GPCR partners exhibited different effects in the physiological regulation and signal transduction of MC3R and MC4R. CONCLUSIONS This work represented the first large-scale screen for the functional GPCR complex of central melanocortin receptors and defined a composite metabolic regulatory GPCR network of the hypothalamic nucleuses.
Collapse
Affiliation(s)
- Yunpeng Li
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xiaozhu Wang
- Shanghai Key Laboratory of Signaling and Disease Research, Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Shanghai East Hospital, Tongji University, Shanghai, China.
| | - Liumei Lu
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Meng Wang
- Department of Plastic and Reconstructive Surgery, Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yue Zhai
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xiaolu Tai
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Diliqingna Dilimulati
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Xiaowei Lei
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jing Xu
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Cong Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yanbin Fu
- Department of Plastic and Reconstructive Surgery, Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shen Qu
- Department of Endocrinology and Metabolism, National Metabolic Management Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China.
| | - Qingfeng Li
- Department of Plastic and Reconstructive Surgery, Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Chao Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| |
Collapse
|
14
|
Ullah R, Rauf N, Nabi G, Yi S, Yu-Dong Z, Fu J. Mechanistic insight into high-fat diet-induced metabolic inflammation in the arcuate nucleus of the hypothalamus. Biomed Pharmacother 2021; 142:112012. [PMID: 34388531 DOI: 10.1016/j.biopha.2021.112012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/31/2021] [Accepted: 08/03/2021] [Indexed: 12/16/2022] Open
Abstract
A high-fat diet (HFD) is linked with cytokines production by non-neuronal cells within the hypothalamus, which mediates metabolic inflammation. These cytokines then activate different inflammatory mediators in the arcuate nucleus of the hypothalamus (ARC), a primary hypothalamic area accommodating proopiomelanocortin (POMC) and agouti-related peptide (AGRP) neurons, first-order neurons that sense and integrate peripheral metabolic signals and then respond accordingly. These mediators, such as inhibitor of κB kinase-β (IKKβ), suppression of cytokine signaling 3 (SOCS3), c-Jun N-terminal kinases (JNKs), protein kinase C (PKC), etc., cause insulin and leptin resistance in POMC and AGRP neurons and support obesity and related metabolic complications. On the other hand, inhibition of these mediators has been shown to counteract the impaired metabolism. Therefore, it is important to discuss the contribution of neuronal and non-neuronal cells in HFD-induced hypothalamic inflammation. Furthermore, understanding few other questions, such as the diets causing hypothalamic inflammation, the gender disparity in response to HFD feeding, and how hypothalamic inflammation affects ARC neurons to cause impaired metabolism, will be helpful for the development of therapeutic approaches to prevent or treat HFD-induced obesity.
Collapse
Affiliation(s)
- Rahim Ullah
- Department of Endocrinology, Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China; Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Naveed Rauf
- Department of Endocrinology, Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China
| | - Ghulam Nabi
- Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang 050024, Hebei Province, China; Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, Pakistan
| | - Shen Yi
- Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China.
| | - Zhou Yu-Dong
- Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China.
| | - Junfen Fu
- Department of Endocrinology, Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China; National Clinical Research Center for Child Health, Hangzhou 310052, China; National Children's Regional Medical Center, Hangzhou 310052, China.
| |
Collapse
|
15
|
Fujikawa T. Central regulation of glucose metabolism in an insulin-dependent and -independent manner. J Neuroendocrinol 2021; 33:e12941. [PMID: 33599044 DOI: 10.1111/jne.12941] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/17/2022]
Abstract
The central nervous system (CNS) contributes significantly to glucose homeostasis. The available evidence indicates that insulin directly acts on the CNS, in particular the hypothalamus, to regulate hepatic glucose production, thereby controlling whole-body glucose metabolism. Additionally, insulin also acts on the brain to regulate food intake and fat metabolism, which may indirectly regulate glucose metabolism. Studies conducted over the last decade have found that the CNS can regulate glucose metabolism in an insulin-independent manner. Enhancement of central leptin signalling reverses hyperglycaemia in insulin-deficient rodents. Here, I review the mechanisms by which central insulin and leptin actions regulate glucose metabolism. Although clinical studies have shown that insulin treatment is currently indispensable for managing diabetes, unravelling the neuronal mechanisms underlying the central regulation of glucose metabolism will pave the way for the design of novel therapeutic drugs for diabetes.
Collapse
Affiliation(s)
- Teppei Fujikawa
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| |
Collapse
|
16
|
Organismal roles for the PI3Kα and β isoforms: their specificity, redundancy or cooperation is context-dependent. Biochem J 2021; 478:1199-1225. [DOI: 10.1042/bcj20210004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 02/07/2023]
Abstract
PI3Ks are important lipid kinases that produce phosphoinositides phosphorylated in position 3 of the inositol ring. There are three classes of PI3Ks: class I PI3Ks produce PIP3 at plasma membrane level. Although D. melanogaster and C. elegans have only one form of class I PI3K, vertebrates have four class I PI3Ks called isoforms despite being encoded by four different genes. Hence, duplication of these genes coincides with the acquisition of coordinated multi-organ development. Of the class I PI3Ks, PI3Kα and PI3Kβ, encoded by PIK3CA and PIK3CB, are ubiquitously expressed. They present similar putative protein domains and share PI(4,5)P2 lipid substrate specificity. Fifteen years after publication of their first isoform-selective pharmacological inhibitors and genetically engineered mouse models (GEMMs) that mimic their complete and specific pharmacological inhibition, we review the knowledge gathered in relation to the redundant and selective roles of PI3Kα and PI3Kβ. Recent data suggest that, further to their redundancy, they cooperate for the integration of organ-specific and context-specific signal cues, to orchestrate organ development, physiology, and disease. This knowledge reinforces the importance of isoform-selective inhibitors in clinical settings.
Collapse
|
17
|
Gaspar RC, Nakandakari SCBR, Muñoz VR, Vieira RFL, da Silva ASR, Cintra DE, de Moura LP, Ropelle ER, Pauli JR. Acute physical exercise increases PI3K-p110α protein content in the hypothalamus of obese mice. J Anat 2021; 238:743-750. [PMID: 33094520 PMCID: PMC7855078 DOI: 10.1111/joa.13342] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 01/19/2023] Open
Abstract
The anatomy of the hypothalamus includes many nuclei and a complex network of neurocircuits. In this context, some hypothalamic nuclei reside closer to the blood-brain barrier, allowing communication with the peripheral organs through some molecules, such as leptin. Leptin is considered the main adipokine for energy homeostasis control. Furthermore, leptin signalling in the hypothalamus can communicate with insulin signalling through the activation of phosphoinositide 3-kinase (PI3k). Previous data suggest that isoforms of PI3k are necessary to mediate insulin action in the hypothalamus. However, obese animals show impairment in the central signalling of these hormones. Thus, in the current study, we evaluated the role of acute exercise in the leptin and insulin pathways in the hypothalamus, as well as in food intake control in obese mice. Although acute physical exercise was not able to modulate leptin signalling, this protocol suppressed the increase in the suppressor of cytokine signalling 3 (SOCS3) protein levels. In addition, acute exercise increased the content of PI3k-p110α protein in the hypothalamus. The exercised animals showed a strong tendency to reduction in cumulative food intake. For the first time, our results indicate physical exercise can increase PI3k-p110α protein content in the hypothalamus of obese mice and regulate food intake.
Collapse
Affiliation(s)
- Rafael C. Gaspar
- Laboratory of Molecular Biology of ExerciseUniversity of Campinas (UNICAMP)LimeiraBrazil
| | | | - Vitor R. Muñoz
- Laboratory of Molecular Biology of ExerciseUniversity of Campinas (UNICAMP)LimeiraBrazil
| | - Renan F. L. Vieira
- Laboratory of Molecular Biology of ExerciseUniversity of Campinas (UNICAMP)LimeiraBrazil
| | - Adelino S. R. da Silva
- Post‐graduate Program in Rehabilitation and Functional PerformanceRibeirão Preto Medical SchoolUSPRibeirão PretoBrazil
| | - Dennys E. Cintra
- Laboratory of Nutritional GenomicsUniversity of Campinas (UNICAMP)LimeiraBrazil,Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC)University of CampinasCampinasBrazil
| | - Leandro P. de Moura
- Laboratory of Molecular Biology of ExerciseUniversity of Campinas (UNICAMP)LimeiraBrazil,Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC)University of CampinasCampinasBrazil,CEPECE ‐ Center of Research in Sport Sciences. School of Applied SciencesUniversity of Campinas (UNICAMP)LimeiraBrazil
| | - Eduardo R. Ropelle
- Laboratory of Molecular Biology of ExerciseUniversity of Campinas (UNICAMP)LimeiraBrazil,Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC)University of CampinasCampinasBrazil,CEPECE ‐ Center of Research in Sport Sciences. School of Applied SciencesUniversity of Campinas (UNICAMP)LimeiraBrazil
| | - José Rodrigo Pauli
- Laboratory of Molecular Biology of ExerciseUniversity of Campinas (UNICAMP)LimeiraBrazil,Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC)University of CampinasCampinasBrazil,CEPECE ‐ Center of Research in Sport Sciences. School of Applied SciencesUniversity of Campinas (UNICAMP)LimeiraBrazil
| |
Collapse
|
18
|
Landry T, Li P, Shookster D, Jiang Z, Li H, Laing BT, Bunner W, Langton T, Tong Q, Huang H. Centrally circulating α-klotho inversely correlates with human obesity and modulates arcuate cell populations in mice. Mol Metab 2020; 44:101136. [PMID: 33301986 PMCID: PMC7777546 DOI: 10.1016/j.molmet.2020.101136] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 12/20/2022] Open
Abstract
Objective Our laboratory recently identified the centrally circulating α-klotho protein as a novel hypothalamic regulator of food intake and glucose metabolism in mice. The current study aimed to investigate novel molecular effectors of central α-klotho in the arcuate nucleus of the hypothalamus (ARC), while further deciphering its role regulating energy balance in both humans and mice. Methods Cerebrospinal fluid (CSF) was collected from 22 adults undergoing lower limb orthopedic surgeries, and correlations between body weight and α-klotho were determined using an α-klotho enzyme-linked immunosorbent assay (ELISA) kit. To investigate the effects of α-klotho on energy expenditure (EE), 2-day intracerebroventricular (ICV) treatment was performed in diet-induced obesity (DIO) mice housed in TSE Phenomaster indirect calorimetry metabolic cages. Immunohistochemical staining for cFOS and patch clamp electrophysiology were used to determine the effects of central α-klotho on proopiomelanocortin (POMC) and tyrosine hydroxylase (TH) neurons. Additional stainings were performed to determine novel roles for central α-klotho to regulate non-neuronal cell populations in the ARC. Lastly, ICV pretreatment with fibroblast growth factor receptor (FGFR) or PI3kinase inhibitors was performed to determine the intracellular signaling involved in α-klotho-mediated regulation of ARC nuclei. Results Obese/overweight human subjects had significantly lower CSF α-klotho concentrations compared to lean counterparts (1,044 ± 251 vs. 1616 ± 218 pmol/L, respectively). Additionally, 2 days of ICV α-klotho treatment increased EE in DIO mice. α-Klotho had no effects on TH neuron activity but elicited varied responses in POMC neurons, with 44% experiencing excitatory and 56% experiencing inhibitory effects. Inhibitor experiments identified an α-klotho→FGFR→PI3kinase signaling mechanism in the regulation of ARC POMC and NPY/AgRP neurons. Acute ICV α-klotho treatment also increased phosphorylated ERK in ARC astrocytes via FGFR signaling. Conclusion Our human CSF data provide the first evidence that impaired central α-klotho function may be involved in the pathophysiology of obesity. Furthermore, results in mouse models identify ARC POMC neurons and astrocytes as novel molecular effectors of central α-klotho. Overall, the current study highlights prominent roles of α-klotho→FGFR→PI3kinase signaling in the homeostatic regulation of ARC neurons and whole-body energy balance. Human CSF α-klotho concentrations exhibit a strong, inverse correlation with body weight and BMI. ICV α-klotho treatment increases energy expenditure in DIO mice. α-Klotho.→FGFR→PI3kinase signaling modulates ARC NPY/AgRP and POMC neurons. α-Klotho.→FGFR→ERK signaling regulates ARC astrocytes.
Collapse
Affiliation(s)
- Taylor Landry
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA
| | - Peixin Li
- Department of Comprehensive Surgery, Medical and Health Center, Beijing Friendship Hospital, Capital Medical University, Beijing, PR China
| | - Daniel Shookster
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA
| | - Zhiying Jiang
- Brown Foundation Institute of Molecular Medicine of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Hongli Li
- Brown Foundation Institute of Molecular Medicine of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Brenton Thomas Laing
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA
| | - Wyatt Bunner
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA
| | - Theodore Langton
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Hu Huang
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA; Department of Physiology, East Carolina University, Greenville, NC, USA.
| |
Collapse
|
19
|
Bougen-Zhukov NM, Lee YY, Lee JYJ, Lee P, Loo LH. PI3K Catalytic Subunits α and β Modulate Cell Death and IL-6 Secretion Induced by Talc Particles in Human Lung Carcinoma Cells. Am J Respir Cell Mol Biol 2020; 62:331-341. [PMID: 31513749 DOI: 10.1165/rcmb.2019-0050oc] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hydrated magnesium silicate (or "talc" particles) is a sclerosis agent commonly used in the management of malignant pleural effusions, a common symptom of metastatic diseases, including lung cancers. However, the direct effects of talc particles to lung carcinoma cells, which can be found in the malignant pleural effusion fluids from patients with lung cancer, are not fully understood. Here, we report a study of the signaling pathways that can modulate the cell death and IL-6 secretion induced by talc particles in human lung carcinoma cells. We found that talc-sensitive cells have higher mRNA and protein expression of PI3K catalytic subunits α and β. Further experiments confirmed that modulation (inhibition or activation) of the PI3K pathway reduces or enhances cellular sensitivity to talc particles, respectively, independent of the inflammasome. By knocking down specific PI3K isoforms, we also confirmed that both PI3Kα and -β mediate the observed talc effects. Our results suggest a novel role of the PI3K pathway in talc-induced cell death and IL-6 secretion in lung carcinoma cells. These cellular events are known to drive fibrosis, and thus further studies of the PI3K pathway may provide a better understanding of the mechanisms of talc sclerosis in the malignant pleural space.
Collapse
Affiliation(s)
| | - Yin Yeng Lee
- Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore, Singapore
| | - Jia-Ying Joey Lee
- Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore, Singapore
| | - Pyng Lee
- Division of Respiratory and Critical Care, National University Hospital, National University Health System, Singapore, Singapore; and
| | - Lit-Hsin Loo
- Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore, Singapore.,Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
20
|
Landry T, Laing BT, Li P, Bunner W, Rao Z, Prete A, Sylvestri J, Huang H. Central α-Klotho Suppresses NPY/AgRP Neuron Activity and Regulates Metabolism in Mice. Diabetes 2020; 69:1368-1381. [PMID: 32332158 PMCID: PMC7306125 DOI: 10.2337/db19-0941] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 04/15/2020] [Indexed: 12/14/2022]
Abstract
α-Klotho is a circulating factor with well-documented antiaging properties. However, the central role of α-klotho in metabolism remains largely unexplored. The current study investigated the potential role of central α-klotho to modulate neuropeptide Y/agouti-related peptide (NPY/AgRP)-expressing neurons, energy balance, and glucose homeostasis. Intracerebroventricular administration of α-klotho suppressed food intake, improved glucose profiles, and reduced body weight in mouse models of type 1 and 2 diabetes. Furthermore, central α-klotho inhibition via an anti-α-klotho antibody impaired glucose tolerance. Ex vivo patch clamp electrophysiology and immunohistochemical analysis revealed that α-klotho suppresses NPY/AgRP neuron activity, at least in part, by enhancing miniature inhibitory postsynaptic currents. Experiments in hypothalamic GT1-7 cells observed that α-klotho induces phosphorylation of AKTser473, ERKthr202/tyr204, and FOXO1ser256 as well as blunts AgRP gene transcription. Mechanistically, fibroblast growth factor receptor 1 (FGFR1) inhibition abolished the downstream signaling of α-klotho, negated its ability to modulate NPY/AgRP neurons, and blunted its therapeutic effects. Phosphatidylinositol 3 kinase (PI3K) inhibition also abolished α-klotho's ability to suppress food intake and improve glucose clearance. These results indicate a prominent role of hypothalamic α-klotho/FGFR1/PI3K signaling in the modulation of NPY/AgRP neuron activity and maintenance of energy homeostasis, thus providing new insight into the pathophysiology of metabolic disease.
Collapse
Affiliation(s)
- Taylor Landry
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Brenton Thomas Laing
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Peixin Li
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Wyatt Bunner
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Zhijian Rao
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Amber Prete
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Julia Sylvestri
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
| | - Hu Huang
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
- Department of Kinesiology, East Carolina University, Greenville, NC
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC
- Department of Physiology, East Carolina University, Greenville, NC
| |
Collapse
|
21
|
Effects of metabolic state on the regulation of melanocortin circuits. Physiol Behav 2020; 224:113039. [PMID: 32610101 PMCID: PMC7387173 DOI: 10.1016/j.physbeh.2020.113039] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 06/01/2020] [Accepted: 06/26/2020] [Indexed: 12/14/2022]
Abstract
Dysfunction in neurophysiological systems that regulate food intake and metabolism are at least partly responsible for obesity and related comorbidities. An important component of this process is the hypothalamic melanocortin system, where an imbalance can result in severe obesity and deficits in glucose metabolism. Exercise offers many health benefits related to cardiovascular improvements, hunger control, and blood glucose homeostasis. However, the molecular mechanism underlying the exercise-induced improvements to the melanocortin system remain undefined. Here, we review the role of the melanocortin system to sense hormonal, nutrient, and neuronal signals of energy status. This information is then relayed onto secondary neurons in order to regulate physiological parameters, which promote proper energy and glucose balance. We also provide an overview on the effects of physical exercise to induce biophysical changes in the melanocortin circuit which may regulate food intake, glucose metabolism and improve overall metabolic health.
Collapse
|
22
|
Sarvestani FS, Zare MA, Saki F, Koohpeyma F, Al-Abdullah IH, Azarpira N. The effect of human wharton's jelly-derived mesenchymal stem cells on MC4R, NPY, and LEPR gene expression levels in rats with streptozotocin-induced diabetes. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2020; 23:214-223. [PMID: 32405365 PMCID: PMC7211357 DOI: 10.22038/ijbms.2019.39582.9387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 08/03/2019] [Indexed: 12/17/2022]
Abstract
OBJECTIVES Type 1 diabetes (T1D) is an autoimmune disease resulting from inflammatory destruction of islets β-cells. Nowadays, progress in cell therapy, especially mesenchymal stem cells (MSCs) proposes numerous potential remedies for T1D. We aimed to investigate the combination therapeutic effect of these cells with insulin and metformin on neuropeptide Y, melanocortin-4 receptor, and leptin receptor genes expression in TID. MATERIALS AND METHODS One hundreds male rats were randomly divided into seven groups: the control, diabetes, insulin (Ins.), insulin+metformin (Ins.Met.), Wharton's Jelly-derived MSCs (WJ-MSCs), insulin+metformin+WJ-MSCs (Ins.Met.MSCs), and insulin+WJ-MSCs (Ins.MSCs). Treatment was performed from the first day after diagnosis as diabetes. Groups of the recipient WJ-MSCs were intraportally injected with 2× 10⁶ MSCs/kg at the 7th and 28th days of study. Fasting blood sugar was monitored and tissues and genes analysis were performed. RESULTS The blood glucose levels were slightly decreased in all treatment groups within 20th and 45th days compared to the diabetic group. The C-peptide level enhanced in these groups compared to the diabetic group, but this increment in Ins.MSCs group on the 45th days was higher than other groups. The expression level of melanocortin-4 receptor and leptin receptor genes meaningfully up-regulated in the treatment groups, while the expression of neuropeptide Y significantly down-regulated in the treatment group on both times of study. CONCLUSION Our data exhibit that infusion of MSCs and its combination therapy with insulin might ameliorate diabetes signs by changing the amount of leptin and subsequent changes in the expression of neuropeptide Y and melanocortin-4 receptor.
Collapse
Affiliation(s)
| | - Mohammad Ali Zare
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Forough Saki
- Endocrinology and Metabolism Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farhad Koohpeyma
- Endocrinology and Metabolism Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ismail H Al-Abdullah
- Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope, Duarte, USA
| | - Negar Azarpira
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| |
Collapse
|
23
|
Landry T, Shookster D, Huang H. Tissue-Specific Approaches Reveal Diverse Metabolic Functions of Rho-Kinase 1. Front Endocrinol (Lausanne) 2020; 11:622581. [PMID: 33633690 PMCID: PMC7901932 DOI: 10.3389/fendo.2020.622581] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 12/22/2020] [Indexed: 01/20/2023] Open
Abstract
Rho-kinase 1 (ROCK1) has been implicated in diverse metabolic functions throughout the body, with promising evidence identifying ROCK1 as a therapeutic target in diabetes and obesity. Considering these metabolic roles, several pharmacological inhibitors have been developed to elucidate the mechanisms underlying ROCK1 function. Y27632 and fasudil are two common ROCK1 inhibitors; however, they have varying non-specific selectivity to inhibit other AGC kinase subfamily members and whole-body pharmacological approaches lack tissue-specific insight. As a result, interpretation of studies with these inhibitors is difficult, and alternative approaches are needed to elucidate ROCK1's tissue specific metabolic functions. Fortunately, recent technological advances utilizing molecular carriers or genetic manipulation have facilitated discovery of ROCK1's tissue-specific mechanisms of action. In this article, we review the tissue-specific roles of ROCK1 in the regulation of energy balance and substrate utilization. We highlight prominent metabolic roles in liver, adipose, and skeletal muscle, in which ROCK1 regulates energy expenditure, glucose uptake, and lipid metabolism via inhibition of AMPK2α and paradoxical modulation of insulin signaling. Compared to ROCK1's roles in peripheral tissues, we also describe contradictory functions of ROCK1 in the hypothalamus to increase energy expenditure and decrease food intake via leptin signaling. Furthermore, dysregulated ROCK1 activity in either of these tissues results in metabolic disease phenotypes. Overall, tissue-specific approaches have made great strides in deciphering the many critical metabolic functions of ROCK1 and, ultimately, may facilitate the development of novel treatments for metabolic disorders.
Collapse
Affiliation(s)
- Taylor Landry
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
- Department of Kinesiology, East Carolina University, Greenville, NC, United States
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, United States
| | - Daniel Shookster
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
- Department of Kinesiology, East Carolina University, Greenville, NC, United States
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, United States
| | - Hu Huang
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
- Department of Kinesiology, East Carolina University, Greenville, NC, United States
- Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, United States
- Department of Physiology, East Carolina University, Greenville, NC, United States
- *Correspondence: Hu Huang,
| |
Collapse
|
24
|
Quarta C, Fioramonti X, Cota D. POMC Neurons Dysfunction in Diet-induced Metabolic Disease: Hallmark or Mechanism of Disease? Neuroscience 2019; 447:3-14. [PMID: 31689486 DOI: 10.1016/j.neuroscience.2019.09.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/19/2019] [Accepted: 09/24/2019] [Indexed: 12/19/2022]
Abstract
One important lesson from the last decade of studies in the field of systemic energy metabolism is that obesity is first and foremost a brain disease. Hypothalamic neurons dysfunction observed in response to chronic metabolic stress is a key pathogenic node linking consumption of hypercaloric diets with body weight gain and associated metabolic sequelae. A key hypothalamic neuronal population expressing the neuropeptide Pro-opio-melanocortin (POMC) displays altered electrical activity and dysregulated neuropeptides production capacity after long-term feeding with hypercaloric diets. However, whether such neuronal dysfunction represents a consequence or a mechanism of disease, remains a subject of debate. Here, we will review and highlight emerging pathogenic mechanisms that explain why POMC neurons undergo dysfunctional activity in response to caloric overload, and critically address whether these mechanisms may be causally implicated in the physiopathology of obesity and of its associated co-morbidities.
Collapse
Affiliation(s)
- Carmelo Quarta
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France.
| | - Xavier Fioramonti
- Université de Bordeaux, Institut National de la Recherche Agronomique, Bordeaux INP, NutriNeuro, UMR 1286, F-33000 Bordeaux, France
| | - Daniela Cota
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France.
| |
Collapse
|
25
|
Buchanan CM, Lee KL, Shepherd PR. For Better or Worse: The Potential for Dose Limiting the On-Target Toxicity of PI 3-Kinase Inhibitors. Biomolecules 2019; 9:biom9090402. [PMID: 31443495 PMCID: PMC6770514 DOI: 10.3390/biom9090402] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/15/2019] [Accepted: 08/21/2019] [Indexed: 02/07/2023] Open
Abstract
The hyper-activation of the phosphoinositide (PI) 3-kinase signaling pathway is a hallmark of many cancers and overgrowth syndromes, and as a result, there has been intense interest in the development of drugs that target the various isoforms of PI 3-kinase. Given the key role PI 3-kinases play in many normal cell functions, there is significant potential for the disruption of essential cellular functions by PI 3-kinase inhibitors in normal tissues; so-called on-target drug toxicity. It is, therefore, no surprise that progress within the clinical development of PI 3-kinase inhibitors as single-agent anti-cancer therapies has been slowed by the difficulty of identifying a therapeutic window. The aim of this review is to place the cellular, tissue and whole-body effects of PI 3-kinase inhibition in the context of understanding the potential for dose limiting on-target toxicities and to introduce possible strategies to overcome these.
Collapse
Affiliation(s)
- Christina M Buchanan
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Kate L Lee
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| |
Collapse
|
26
|
Gaspar RC, Muñoz VR, Kuga GK, Nakandakari SCBR, Crisol BM, Lenhare L, Breda L, Botezelli JD, Sant'Ana MR, Silva ASR, Cintra DE, Moura LP, Ropelle ER, Pauli JR. Acute physical exercise increases
APPL
1/
PI
3K signaling in the hypothalamus of lean mice. Eur J Neurosci 2019; 50:3181-3190. [DOI: 10.1111/ejn.14490] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 04/27/2019] [Accepted: 05/22/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Rafael Calais Gaspar
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
| | - Vitor Rosetto Muñoz
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
| | - Gabriel Keine Kuga
- Post‐graduate Program in Movement Sciences São Paulo State University (UNESP) Rio Claro Brazil
| | | | - Barbara Moreira Crisol
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
| | - Luciene Lenhare
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
| | - Leonardo Breda
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
| | - José Diego Botezelli
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
| | | | - Adelino S. R. Silva
- Postgraduate Program in Rehabilitation and Functional Performance Ribeirão Preto Medical School, and Postgraduate Program in Physical Education and Sport School of Physical Education and Sport of Ribeirão Preto University of São Paulo (USP) Ribeirão Preto Brazil
| | - Dennys Esper Cintra
- Laboratory of Nutritional Genomics (LabGeN) University of Campinas (UNICAMP) Limeira Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC) University of Campinas Campinas Brazil
| | - Leandro Pereira Moura
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC) University of Campinas Campinas Brazil
- School of Applied Sciences CEPECE – Center of Research in Sport Sciences University of Campinas (UNICAMP) Limeira Brazil
| | - Eduardo Rochete Ropelle
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC) University of Campinas Campinas Brazil
- School of Applied Sciences CEPECE – Center of Research in Sport Sciences University of Campinas (UNICAMP) Limeira Brazil
| | - José Rodrigo Pauli
- Laboratory of Molecular Biology of Exercise (LaBMEx) University of Campinas (UNICAMP) Limeira Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center (OCRC) University of Campinas Campinas Brazil
- School of Applied Sciences CEPECE – Center of Research in Sport Sciences University of Campinas (UNICAMP) Limeira Brazil
| |
Collapse
|
27
|
Qiu J, Bosch MA, Zhang C, Rønnekleiv OK, Kelly MJ. Estradiol Protects Neuropeptide Y/Agouti-Related Peptide Neurons against Insulin Resistance in Females. Neuroendocrinology 2019; 110:105-118. [PMID: 31212279 PMCID: PMC6920578 DOI: 10.1159/000501560] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 06/17/2019] [Indexed: 12/18/2022]
Abstract
When it comes to obesity, men exhibit a higher incidence of metabolic syndrome than women in early adult life, but this sex advantage wanes in postmenopausal women. A key diagnostic of the metabolic syndrome is insulin resistance in both peripheral tissues and brain, especially in the hypothalamus. Since the anorexigenic hormone 17β-estradiol (E2) regulates food intake in part by inhibiting the excitability of the hypothalamic neuropeptide Y/agouti-related peptide (NPY/AgRP) neurons, we hypothesized that E2 would protect against insulin resistance in NPY/AgRP neurons with diet-induced obesity (DIO). Therefore, we did whole-cell recordings and single cell quantitative polymerase chain reaction in arcuate NPYGFP neurons from both female and male mice to test the efficacy of insulin with DIO. The resting membrane potential and input resistance of NPY/AgRP neurons were significantly increased in DIO versus control-diet fed males. Most notably, the efficacy of insulin to activate KATP channels in NPY/AgRP neurons was significantly attenuated, although the KATP channel opener diazoxide was fully effective in NPY/AgRP neurons from DIO males, indicating that the KATP channels were expressed and functional. In contrast, insulin was fully efficacious to activate KATP channels in DIO females, and the response was reversed by the KATP channel blocker tolbutamide. However, the ability of insulin to activate KATP channels was abrogated with ovariectomy but fully restored with E2 replacement. Insulin resistance in obese males was likely mediated by an increase in suppressor of cytokine signaling-3 (SOCS-3), protein tyrosine phosphatase B (PTP1B) and T-cell protein tyrosine phosphatase (TCPTP) activity, since the expression of all 3 mRNAs were upregulated in the obese males but not in females. As proof of principle, pre-incubation of hypothalamic slices from DIO males with the PTP1B/TCPTP inhibitor CX08005 completely rescued the effects of insulin. Therefore, E2 protects NPY/AgRP neurons in females against insulin resistance through, at least in part, attenuating phosphatase activity. The neuroprotective effects of E2 may explain sex differences in the expression of metabolic syndrome that disappears with the loss of E2 in aging.
Collapse
Affiliation(s)
- Jian Qiu
- Department of Physiology and Pharmacology, Oregon Health
& Science University, Portland, Oregon, USA
| | - Martha A. Bosch
- Department of Physiology and Pharmacology, Oregon Health
& Science University, Portland, Oregon, USA
| | - Chunguang Zhang
- Department of Physiology and Pharmacology, Oregon Health
& Science University, Portland, Oregon, USA
| | - Oline K. Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health
& Science University, Portland, Oregon, USA
- Division of Neuroscience, National Primate Research Center,
Oregon Health & Science University, Beaverton, Oregon, USA
| | - Martin J. Kelly
- Department of Physiology and Pharmacology, Oregon Health
& Science University, Portland, Oregon, USA
- Division of Neuroscience, National Primate Research Center,
Oregon Health & Science University, Beaverton, Oregon, USA
| |
Collapse
|
28
|
Saito K, Davis KC, Morgan DA, Toth BA, Jiang J, Singh U, Berglund ED, Grobe JL, Rahmouni K, Cui H. Celastrol Reduces Obesity in MC4R Deficiency and Stimulates Sympathetic Nerve Activity Affecting Metabolic and Cardiovascular Functions. Diabetes 2019; 68:1210-1220. [PMID: 30894367 PMCID: PMC6610022 DOI: 10.2337/db18-1167] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/15/2019] [Indexed: 12/19/2022]
Abstract
Leptin resistance is a hallmark of obesity with unclear etiology. Celastrol, a compound found in the roots of the Tripterygium wilfordii and known to reduce endoplasmic reticulum (ER) stress, has recently emerged as a promising candidate to treat obesity by improving leptin sensitivity. However, the underlying neural mechanisms by which celastrol reduces obesity remain unclear. Using three different mouse models of obesity-diet-induced obesity (DIO), leptin receptor (LepR)-null, and melanocortin 4 receptor (MC4R)-null mice-in this study, we show that systemic celastrol administration substantially reduces food intake and body weight in MC4R-null comparable to DIO, proving the MC4R-independent antiobesity effect of celastrol. Body weight reduction was due to decreases in both fat and lean mass, and modest but significant body weight reduction was also observed in nonobese wild-type and LepR-null mice. Unexpectedly, celastrol upregulated proinflammatory cytokines without affecting genes involved in ER stress. Importantly, celastrol steadily increased sympathetic nerve activity to the brown fat and kidney with concordant increases of resting metabolic rate and arterial pressure. Our results suggest a previously unappreciated mechanism of action of celastrol in the regulation of energy homeostasis and highlight the need for careful consideration of its development as a safe antiobesity medication.
Collapse
Affiliation(s)
- Kenji Saito
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Kevin C Davis
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Donald A Morgan
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Brandon A Toth
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Jingwei Jiang
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Uday Singh
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Eric D Berglund
- Advanced Imaging Research Center and Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX
| | - Justin L Grobe
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA
- Obesity Research and Educational Initiative, University of Iowa Carver College of Medicine, Iowa City, IA
- Iowa Neuroscience Institute, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA
- Obesity Research and Educational Initiative, University of Iowa Carver College of Medicine, Iowa City, IA
- Iowa Neuroscience Institute, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Huxing Cui
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA
- Obesity Research and Educational Initiative, University of Iowa Carver College of Medicine, Iowa City, IA
- Iowa Neuroscience Institute, University of Iowa Carver College of Medicine, Iowa City, IA
| |
Collapse
|
29
|
Inagaki-Ohara K. Gastric Leptin and Tumorigenesis: Beyond Obesity. Int J Mol Sci 2019; 20:ijms20112622. [PMID: 31141984 PMCID: PMC6600422 DOI: 10.3390/ijms20112622] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 05/24/2019] [Accepted: 05/24/2019] [Indexed: 12/13/2022] Open
Abstract
Leptin, an adipocyte-derived hormone and its receptor (ObR) expressed in the hypothalamus are well known as an essential regulator of appetite and energy expenditure. Obesity induces abundant leptin production, however, reduced sensitivity to leptin leads to the development of metabolic disorders, so called leptin resistance. The stomach has been identified as an organ that simultaneously expresses leptin and ObR. Accumulating evidence has shown gastric leptin to perform diverse functions, such as those in nutrient absorption and carcinogenesis in the gastrointestinal system, independent of its well-known role in appetite regulation and obesity. Overexpression of leptin and phosphorylated ObR is implicated in gastric cancer in humans and in murine model, and diet-induced obesity causes precancerous lesions in the stomach in mice. While the underlying pathomechanisms remain unclear, leptin signaling can affect gastric mucosal milieu. In this review, we focus on the significant role of the gastric leptin signaling in neoplasia and tumorigenesis in stomach in the context of hereditary and diet-induced obesity.
Collapse
Affiliation(s)
- Kyoko Inagaki-Ohara
- Division of Host Defense, Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 5562 Nanatsuka, Shobara, Hiroshima 727-0023, Japan.
| |
Collapse
|
30
|
Garcia-Galiano D, Borges BC, Allen SJ, Elias CF. PI3K signalling in leptin receptor cells: Role in growth and reproduction. J Neuroendocrinol 2019; 31:e12685. [PMID: 30618188 PMCID: PMC6533139 DOI: 10.1111/jne.12685] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/04/2019] [Accepted: 01/04/2019] [Indexed: 12/15/2022]
Abstract
Nutrition and growth are important signals for pubertal development, although how they are perceived and integrated in brain circuits has not been well defined. Growth hormones and metabolic cues both recruit phosphatidylinositol 3-kinase (PI3K) signalling in hypothalamic sites, although whether they converge into the same neuronal population(s) is also not known. In this review, we discuss recent findings from our laboratory showing the role of PI3K subunits in cells directly responsive to the adipocyte-derived hormone leptin in the coordination of growth, pubertal development and fertility. Mice with deletion of PI3K p110α and p110β catalytic subunits in leptin receptor cells (LRΔα+β ) have a lean phenotype associated with increased energy expenditure, locomotor activity and thermogenesis. The LRΔα+β mice also show deficient growth and delayed puberty. Deletion of a single subunit (ie, p110α) in LR cells (LRΔα ) causes a similar phenotype of increased energy expenditure, deficient growth and delayed pubertal development, indicating that these functions are preferably controlled by p110α. The LRΔα mice show enhanced leptin sensitivity in metabolic regulation but, remarkably, these mice are unresponsive to the effects of leptin on growth and puberty. PI3K is also recruited by insulin and a subpopulation of LR neurones is responsive to i.c.v. insulin administration. Deletion of insulin receptor in LR cells causes no changes in body weight or linear growth and induces only a mild delay in pubertal completion. Our findings demonstrate that PI3K in LR cells plays an essential role in growth and reproduction. We will also discuss the potential neural pathways underlying these effects.
Collapse
Affiliation(s)
- David Garcia-Galiano
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Beatriz C. Borges
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Kresge Hearing Research Institute and Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Susan J. Allen
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Carol F. Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
31
|
Fujikawa T, Choi YH, Yang DJ, Shin DM, Donato J, Kohno D, Lee CE, Elias CF, Lee S, Kim KW. P110β in the ventromedial hypothalamus regulates glucose and energy metabolism. Exp Mol Med 2019; 51:1-9. [PMID: 31028248 PMCID: PMC6486607 DOI: 10.1038/s12276-019-0249-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 01/10/2019] [Accepted: 01/23/2019] [Indexed: 12/29/2022] Open
Abstract
Phosphoinositide 3-kinase (PI3K) signaling in hypothalamic neurons integrates peripheral metabolic cues, including leptin and insulin, to coordinate systemic glucose and energy homeostasis. PI3K is composed of different subunits, each of which has several unique isoforms. However, the role of the PI3K subunits and isoforms in the ventromedial hypothalamus (VMH), a prominent site for the regulation of glucose and energy homeostasis, is unclear. Here we investigated the role of subunit p110β in steroidogenic factor-1 (SF-1) neurons of the VMH in the regulation of metabolism. Our data demonstrate that the deletion of p110β in SF-1 neurons disrupts glucose metabolism, rendering the mice insulin resistant. In addition, the deletion of p110β in SF-1 neurons leads to the whitening of brown adipose tissues and increased susceptibility to diet-induced obesity due to blunted energy expenditure. These results highlight a critical role for p110β in the regulation of glucose and energy homeostasis via VMH neurons. A particular subunit of a critical signaling enzyme is needed for neurons inside the brain’s hypothalamus to properly regulate energy metabolism. Ki Woo Kim from Yonsei University College of Dentistry, Seoul, South Korea, and colleagues explored the role that the PI3K enzyme plays in neurons of the ventromedial area toward the front of the hypothalamus, a region involved in regulating hunger and metabolism. Deleting a subunit of PI3K called p110β, which is needed for enzymatic function, made mice less responsive to insulin, the hormone that keeps blood sugar levels at healthy levels. As well as having abnormal glucose metabolism, the mice converted more brown fat, which burns energy, into white fat, which stores energy. They were also more susceptible to diet-induced obesity. The findings point toward p110β as a potential drug target for treating diabetes.
Collapse
Affiliation(s)
- Teppei Fujikawa
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Cellular and Integrative Physiology, Long School of Medicine, UT Health San Antonio, San Antonio, TX, USA
| | - Yun-Hee Choi
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - Dong Joo Yang
- Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - Dong Min Shin
- Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - Jose Donato
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, 05508000, Brazil
| | - Daisuke Kohno
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, 371-8512, Japan
| | - Charlotte E Lee
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Carol F Elias
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Syann Lee
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Ki Woo Kim
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA. .,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA. .,Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea.
| |
Collapse
|
32
|
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: 125] [Impact Index Per Article: 25.0] [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
|
33
|
Singha AK, Yamaguchi J, Gonzalez NS, Ahmed N, Toney GM, Fujikawa T. Glucose-Lowering by Leptin in the Absence of Insulin Does Not Fully Rely on the Central Melanocortin System in Male Mice. Endocrinology 2019; 160:651-663. [PMID: 30698681 PMCID: PMC6388659 DOI: 10.1210/en.2018-00907] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 01/24/2019] [Indexed: 12/11/2022]
Abstract
Central leptin administration can ameliorate hyperglycemia in insulin-deficient rodent models independently of insulin; however, the underlying neuronal mechanism are unclear. Here, we investigate the contribution of key elements within the central melanocortin system by examining whether central leptin injection can ameliorate hyperglycemia in total insulin-deficient mice that either lacked melanocortin 4 receptors (MC4Rs) in the whole body [knockout (KO); MC4R KO] or selectively, in single-minded homolog 1 (SIM1)-expressing neurons (SIM1ΔMC4R). We further investigated the contribution of leptin receptors (LEPRs) in agouti-related protein (AgRP)-expressing neurons (AgRP∆LEPR). Leptin injections into the cerebral ventricle attenuated mortality and elevated blood glucose in total insulin-deficient MC4R KO mice. Total insulin-deficient SIM1ΔMC4R mice exhibited the same magnitude reduction of blood glucose in response to leptin injections as MC4R KO mice, suggesting SIM1 neurons are key to MC4R-mediated, insulin-independent, glucose-lowering effects of leptin. Central leptin injection also partially rescued glucose levels in total insulin-deficient AgRP∆LEPR mice. In brain slice studies, basal discharge of AgRP neurons from mice with total insulin deficiency was increased and leptin partially reduced their firing rate without membrane potential hyperpolarization. Collectively, our findings indicate that, contrary to glucose-lowering effects of leptin in the presence of insulin or partial insulin deficiency, MC4Rs in SIM1 neurons and LEPRs in AgRP neurons are not solely responsible for glucose-lowering effects of leptin in total insulin deficiency. This indicates that the central melanocortin system operates with other neuronal systems to fully mediate glucose-lowering effects of leptin in an insulin-independent manner.
Collapse
Affiliation(s)
- Ashish K Singha
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
| | - Junya Yamaguchi
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
| | - Nancy S Gonzalez
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
| | - Newaz Ahmed
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Glenn M Toney
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
- Center for Biomedical Neuroscience, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
| | - Teppei Fujikawa
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
- Center for Biomedical Neuroscience, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
- Mouse Genome Engineering and Transgenic Facility, Long School of Medicine, University of Texas Health San Antonio, San Antonio, Texas
- Correspondence: Teppei Fujikawa, PhD, University of Texas Health San Antonio, 7703 Floyd Curl Drive, San Antonio, Texas 78229. E-mail:
| |
Collapse
|
34
|
Bresnick AR, Backer JM. PI3Kβ-A Versatile Transducer for GPCR, RTK, and Small GTPase Signaling. Endocrinology 2019; 160:536-555. [PMID: 30601996 PMCID: PMC6375709 DOI: 10.1210/en.2018-00843] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/20/2018] [Indexed: 12/17/2022]
Abstract
The phosphoinositide 3-kinase (PI3K) family includes eight distinct catalytic subunits and seven regulatory subunits. Only two PI3Ks are directly regulated downstream from G protein-coupled receptors (GPCRs): the class I enzymes PI3Kβ and PI3Kγ. Both enzymes produce phosphatidylinositol 3,4,5-trisposphate in vivo and are regulated by both heterotrimeric G proteins and small GTPases from the Ras or Rho families. However, PI3Kβ is also regulated by direct interactions with receptor tyrosine kinases (RTKs) and their tyrosine phosphorylated substrates, and similar to the class II and III PI3Ks, it binds activated Rab5. The unusually complex regulation of PI3Kβ by small and trimeric G proteins and RTKs leads to a rich landscape of signaling responses at the cellular and organismic levels. This review focuses first on the regulation of PI3Kβ activity in vitro and in cells, and then summarizes the biology of PI3Kβ signaling in distinct tissues and in human disease.
Collapse
Affiliation(s)
- Anne R Bresnick
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York
| | - Jonathan M Backer
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York
| |
Collapse
|
35
|
de Araujo TM, Razolli DS, Correa-da-Silva F, de Lima-Junior JC, Gaspar RS, Sidarta-Oliveira D, Victorio SC, Donato J, Kim YB, Velloso LA. The partial inhibition of hypothalamic IRX3 exacerbates obesity. EBioMedicine 2018; 39:448-460. [PMID: 30522931 PMCID: PMC6354701 DOI: 10.1016/j.ebiom.2018.11.048] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/21/2018] [Accepted: 11/22/2018] [Indexed: 12/01/2022] Open
Abstract
Background The Iroquois homeobox 3 (Irx3) gene has been identified as a functional long-range target of obesity-associated variants within the fat mass and obesity-associated protein (FTO) gene. It is highly expressed in the hypothalamus, and both whole-body knockout and hypothalamic restricted abrogation of its expression results in a lean phenotype, which is mostly explained by the resulting increased energy expenditure in the brown adipose tissue. Because of its potential implication in the pathogenesis of obesity, we evaluated the hypothalamic cell distribution of Irx3 and the outcomes of inhibiting its expression in a rodent model of diet-induced obesity. Methods Bioinformatics tools were used to evaluate the correlations between hypothalamic Irx3 and neurotransmitters, markers of thermogenesis and obesity related phenotypes. Droplet-sequencing analysis in >20,000 hypothalamic cells was used to explore the types of hypothalamic cells expressing Irx3. Lentivirus was used to inhibit hypothalamic Irx3 and the resulting phenotype was studied. Findings IRX3 is expressed predominantly in POMC neurons. Its expression is inhibited during prolonged fasting, as well as when mice are fed a high-fat diet. The partial inhibition of hypothalamic Irx3 using a lentivirus resulted in increased diet-induced body mass gain and adiposity due to increased caloric intake and reduced energy expenditure. Interpretation Contrary to the results obtained when lean mice are submitted to complete inhibition of Irx3, partial inhibition of hypothalamic Irx3 in obese mice causes an exacerbation of the obese phenotype. These data suggest that at least some of the Irx3 functions in the hypothalamus are regulated according to a hormetic pattern, and modulation of its expression can be a novel approach to modifying the body's energy-handling regulation. Fund Sao Paulo Research Foundation grants 2013/07607-8 (LAV) and 2017/02983-2 (JDJ); NIH grants R01DK083567 (YBK).
Collapse
Affiliation(s)
- Thiago Matos de Araujo
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil; Divison of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Daniela S Razolli
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil
| | - Felipe Correa-da-Silva
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil
| | - Jose C de Lima-Junior
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil
| | - Rodrigo S Gaspar
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil
| | - Davi Sidarta-Oliveira
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil
| | - Sheila C Victorio
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Young-Bum Kim
- Divison of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Licio A Velloso
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, State University of Campinas (UNICAMP), Brazil.
| |
Collapse
|
36
|
Smith MA, Katsouri L, Virtue S, Choudhury AI, Vidal-Puig A, Ashford MLJ, Withers DJ. Calcium Channel Ca V2.3 Subunits Regulate Hepatic Glucose Production by Modulating Leptin-Induced Excitation of Arcuate Pro-opiomelanocortin Neurons. Cell Rep 2018; 25:278-287.e4. [PMID: 30304668 PMCID: PMC6198286 DOI: 10.1016/j.celrep.2018.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 07/26/2018] [Accepted: 09/07/2018] [Indexed: 11/18/2022] Open
Abstract
Leptin acts on hypothalamic pro-opiomelanocortin (POMC) neurons to regulate glucose homeostasis, but the precise mechanisms remain unclear. Here, we demonstrate that leptin-induced depolarization of POMC neurons is associated with the augmentation of a voltage-gated calcium (CaV) conductance with the properties of the "R-type" channel. Knockdown of the pore-forming subunit of the R-type (CaV2.3 or Cacna1e) conductance in hypothalamic POMC neurons prevented sustained leptin-induced depolarization. In vivo POMC-specific Cacna1e knockdown increased hepatic glucose production and insulin resistance, while body weight, feeding, or leptin-induced suppression of food intake were not changed. These findings link Cacna1e function to leptin-mediated POMC neuron excitability and glucose homeostasis and may provide a target for the treatment of diabetes.
Collapse
Affiliation(s)
- Mark A Smith
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK.
| | - Loukia Katsouri
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK
| | - Samuel Virtue
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Agharul I Choudhury
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK
| | - Antonio Vidal-Puig
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Michael L J Ashford
- Division of Molecular and Clinical Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Dominic J Withers
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, London W12 0NN, UK; Institute of Clinical Sciences, Imperial College London, Du Cane Road, London W12 0NN, UK.
| |
Collapse
|
37
|
Kelly MJ, Qiu J, Rønnekleiv OK. TRPCing around the hypothalamus. Front Neuroendocrinol 2018; 51:116-124. [PMID: 29859883 PMCID: PMC6175656 DOI: 10.1016/j.yfrne.2018.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/29/2018] [Accepted: 05/30/2018] [Indexed: 01/13/2023]
Abstract
All of the canonical transient receptor potential channels (TRPC) with the exception of TRPC 2 are expressed in hypothalamic neurons and are involved in multiple homeostatic functions. Although the metabotropic glutamate receptors have been shown to be coupled to TRPC channel activation in cortical and sub-cortical brain regions, in the hypothalamus multiple amine and peptidergic G protein-coupled receptors (GPCRs) and growth factor/cytokine receptors are linked to activation of TRPC channels that are vital for reproduction, temperature regulation, arousal and energy homeostasis. In addition to the neurotransmitters, circulating hormones like insulin and leptin through their cognate receptors activate TRPC channels in POMC neurons. Many of the post-synaptic effects of the neurotransmitters and hormones are regulated in different physiological states by expression of TRPC channels in the post-synaptic neurons. Therefore, TRPC channels are key targets not only for neurotransmitters but circulating hormones in their vital role to control multiple hypothalamic functions, which is the focus of this review.
Collapse
Affiliation(s)
- Martin J Kelly
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, USA; Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA.
| | - Jian Qiu
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, USA
| | - Oline K Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, USA; Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| |
Collapse
|
38
|
Huang X, Liu G, Guo J, Su Z. The PI3K/AKT pathway in obesity and type 2 diabetes. Int J Biol Sci 2018; 14:1483-1496. [PMID: 30263000 PMCID: PMC6158718 DOI: 10.7150/ijbs.27173] [Citation(s) in RCA: 816] [Impact Index Per Article: 136.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/10/2018] [Indexed: 02/06/2023] Open
Abstract
Obesity and type 2 diabetes mellitus are complicated metabolic diseases that affect multiple organs and are characterized by hyperglycaemia. Currently, stable and effective treatments for obesity and type 2 diabetes mellitus are not available. Therefore, the mechanisms leading to obesity and diabetes and more effective ways to treat obesity and diabetes should be identified. Based on accumulated evidences, the PI3K/AKT signalling pathway is required for normal metabolism due to its characteristics, and its imbalance leads to the development of obesity and type 2 diabetes mellitus. This review focuses on the role of PI3K/AKT signalling in the skeletal muscle, adipose tissue, liver, brain and pancreas, and discusses how this signalling pathway affects the development of the aforementioned diseases. We also summarize evidences for recently identified therapeutic targets of the PI3K/AKT pathway as treatments for obesity and type 2 diabetes mellitus. PI3K/AKT pathway damaged in various tissues of the body leads to obesity and type 2 diabetes as the result of insulin resistance, and in turn, insulin resistance exacerbates the PI3K/AKT pathway, forming a vicious circle.
Collapse
Affiliation(s)
- Xingjun Huang
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou (510006), China.,Guangdong Metabolic Diseases Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou (510006), China
| | - Guihua Liu
- Shenzhen Center for Disease Control and Prevention, 8 Longyuan Road, Nanshan District, Shenzhen (518055), China
| | - Jiao Guo
- Guangdong Metabolic Diseases Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou (510006), China
| | - Zhengquan Su
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou (510006), China.,Guangdong Metabolic Diseases Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou (510006), China
| |
Collapse
|
39
|
Stincic TL, Rønnekleiv OK, Kelly MJ. Diverse actions of estradiol on anorexigenic and orexigenic hypothalamic arcuate neurons. Horm Behav 2018; 104:146-155. [PMID: 29626486 PMCID: PMC6196116 DOI: 10.1016/j.yhbeh.2018.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 03/29/2018] [Accepted: 04/02/2018] [Indexed: 12/13/2022]
Abstract
Contribution to Special Issue on Fast effects of steroids. There is now compelling evidence for membrane-associated estrogen receptors in hypothalamic neurons that are critical for the hypothalamic control of homeostatic functions. It has been known for some time that estradiol (E2) can rapidly alter hypothalamic neuronal activity within seconds, indicating that some cellular effects can occur via membrane initiated events. However, our understanding of how E2 signals via membrane-associated receptors and how these signals impact physiological functions is only just emerging. Thus, E2 can affect second messenger systems including calcium mobilization and a plethora of kinases to alter cell excitability and even gene transcription in hypothalamic neurons. One population of hypothalamic neurons, the anorexigenic proopiomelanocortin (POMC) neurons, has long been considered to be a target of E2's actions based on gene (Pomc) expression studies. However, we now know that E2 can rapidly alter POMC neuronal activity within seconds and activate several intracellular signaling cascades that ultimately affect gene expression, actions which are critical for maintaining sensitivity to insulin in metabolically stressed states. E2 also affects the orexigenic Neuropeptide Y/Agouti-related Peptide (NPY/AgRP) neurons in similarly rapid but antagonistic manner. Therefore, this review will summarize our current state of knowledge of how E2 signals via rapid membrane-initiated and intracellular signaling cascades in POMC and NPY/AgRP neurons to regulate energy homeostasis.
Collapse
Affiliation(s)
- Todd L Stincic
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Oline K Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239, USA; Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University, Portland, OR 97239, USA; Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Martin J Kelly
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239, USA; Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA.
| |
Collapse
|
40
|
Huang Y, He Z, Gao Y, Lieu L, Yao T, Sun J, Liu T, Javadi C, Box M, Afrin S, Guo H, Williams KW. Phosphoinositide 3-Kinase Is Integral for the Acute Activity of Leptin and Insulin in Male Arcuate NPY/AgRP Neurons. J Endocr Soc 2018; 2:518-532. [PMID: 29850651 PMCID: PMC5961025 DOI: 10.1210/js.2018-00061] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/23/2018] [Indexed: 11/19/2022] Open
Abstract
Neuropeptide Y (NPY)/Agouti-related protein (AgRP) neurons in the arcuate nucleus of the hypothalamus are part of a neuroendocrine feedback loop that regulates feeding behavior and glucose homeostasis. NPY/AgRP neurons sense peripheral signals (including the hormones leptin, insulin, and ghrelin) and integrate those signals with inputs from other brain regions. These inputs modify both long-term changes in gene transcription and acute changes in the electrical activity of these neurons, leading to a coordinated response to maintain energy and glucose homeostasis. However, the mechanisms by which the hormones insulin and leptin acutely modify the electrical activity of these neurons remain unclear. In this study, we show that loss of the phosphoinositide 3-kinase catalytic subunits p110α and p110β in AgRP neurons abrogates the leptin- and insulin-induced inhibition of AgRP neurons. Moreover, continual disruption of p110α and p110β in AgRP neurons results in increased weight gain. The increased adiposity was concomitant with a hypometabolic phenotype: decreased energy expenditure independent of changes in food intake. Deficiency of p110α and p110β in AgRP neurons also impaired glucose homeostasis and insulin sensitivity. In summary, these data highlight the requirement of both p110α and p110β in AgRP neurons for the proper regulation of energy balance and glucose homeostasis.
Collapse
Affiliation(s)
- Yiru Huang
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Zhenyan He
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Yong Gao
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas.,National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Linh Lieu
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Ting Yao
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Jia Sun
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Tiemin Liu
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Chris Javadi
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Maria Box
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Sadia Afrin
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Hongbo Guo
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Kevin W Williams
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
41
|
Haissaguerre M, Ferrière A, Simon V, Saucisse N, Dupuy N, André C, Clark S, Guzman-Quevedo O, Tabarin A, Cota D. mTORC1-dependent increase in oxidative metabolism in POMC neurons regulates food intake and action of leptin. Mol Metab 2018; 12:98-106. [PMID: 29699927 PMCID: PMC6001919 DOI: 10.1016/j.molmet.2018.04.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 04/05/2018] [Accepted: 04/07/2018] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVE Nutrient availability modulates reactive oxygen species (ROS) production in the hypothalamus. In turn, ROS regulate hypothalamic neuronal activity and feeding behavior. The mechanistic target of rapamycin complex 1 (mTORC1) pathway is an important cellular integrator of the action of nutrients and hormones. Here we tested the hypothesis that modulation of mTORC1 activity, particularly in Proopiomelanocortin (POMC)-expressing neurons, mediates the cellular and behavioral effects of ROS. METHODS C57BL/6J mice or controls and their knockout (KO) littermates deficient either for the mTORC1 downstream target 70-kDa ribosomal protein S6 kinase 1 (S6K1) or for the mTORC1 component Rptor specifically in POMC neurons (POMC-rptor-KO) were treated with an intracerebroventricular (icv) injection of the ROS hydrogen peroxide (H2O2) or the ROS scavenger honokiol, alone or, respectively, in combination with the mTORC1 inhibitor rapamycin or the mTORC1 activator leptin. Oxidant-related signal in POMC neurons was assessed using dihydroethidium (DHE) fluorescence. RESULTS Icv administration of H2O2 decreased food intake, while co-administration of rapamycin, whole-body deletion of S6K1, or deletion of rptor in POMC neurons impeded the anorectic action of H2O2. H2O2 also increased oxidant levels in POMC neurons, an effect that hinged on functional mTORC1 in these neurons. Finally, scavenging ROS prevented the hypophagic action of leptin, which in turn required mTORC1 to increase oxidant levels in POMC neurons and to inhibit food intake. CONCLUSIONS Our results demonstrate that ROS and leptin require mTORC1 pathway activity in POMC neurons to increase oxidant levels in POMC neurons and consequently decrease food intake.
Collapse
Affiliation(s)
- Magalie Haissaguerre
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; Department of Endocrinology, Hôpital Haut Lévèque, CHU Bordeaux, F-33600 Pessac, France
| | - Amandine Ferrière
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; Department of Endocrinology, Hôpital Haut Lévèque, CHU Bordeaux, F-33600 Pessac, France
| | - Vincent Simon
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France
| | - Nicolas Saucisse
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France
| | - Nathalie Dupuy
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France
| | - Caroline André
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France
| | - Samantha Clark
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France
| | - Omar Guzman-Quevedo
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France
| | - Antoine Tabarin
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; Department of Endocrinology, Hôpital Haut Lévèque, CHU Bordeaux, F-33600 Pessac, France
| | - Daniela Cota
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France.
| |
Collapse
|
42
|
Qiu J, Bosch MA, Meza C, Navarro UV, Nestor CC, Wagner EJ, Rønnekleiv OK, Kelly MJ. Estradiol Protects Proopiomelanocortin Neurons Against Insulin Resistance. Endocrinology 2018; 159:647-664. [PMID: 29165691 PMCID: PMC5774249 DOI: 10.1210/en.2017-00793] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/01/2017] [Indexed: 12/24/2022]
Abstract
Insulin resistance is at the core of the metabolic syndrome, and men exhibit a higher incidence of metabolic syndrome than women in early adult life, but this sex advantage diminishes sharply when women reach the postmenopausal state. Because 17β-estradiol (E2) augments the excitability of the anorexigenic proopiomelanocortin (POMC) neurons, we investigated the neuroprotective effects of E2 against insulin resistance in POMC neurons from diet-induced obese (DIO) female and male mice. The efficacy of insulin to activate canonical transient receptor potential 5 (TRPC5) channels and depolarize POMC neurons was significantly reduced in DIO male mice but not in DIO female mice. However, the insulin response in POMC neurons was abrogated in ovariectomized DIO females but restored with E2 replacement. E2 increased T-type calcium channel Cav3.1 messenger RNA (mRNA) expression and whole-cell currents but downregulated stromal-interaction molecule 1 mRNA, which rendered POMC neurons more excitable and responsive to insulin-mediated TRPC5 channel activation. Moreover, E2 prevented the increase in suppressor of cytokine signaling-3 mRNA expression with DIO as seen in DIO males. As proof of principle, insulin [intracerebroventricular injection into the third ventricle (ICV)] decreased food intake and increased metabolism in female but not male guinea pigs fed a high-fat diet. The uncoupling of the insulin receptor from its downstream effector system was corroborated by the reduced expression of phosphorylated protein kinase B in the arcuate nucleus of male but not female guinea pigs following insulin. Therefore, E2 protects female POMC neurons from insulin resistance by enhancing POMC neuronal excitability and the coupling of insulin receptor to TRPC5 channel activation.
Collapse
Affiliation(s)
- Jian Qiu
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97239
| | - Martha A. Bosch
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97239
| | - Cecilia Meza
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific Western University of Health Sciences, Pomona, California 91766
| | - Uyen-Vy Navarro
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97239
| | - Casey C Nestor
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97239
| | - Edward J. Wagner
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific Western University of Health Sciences, Pomona, California 91766
| | - Oline K. Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97239
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon 97006
| | - Martin J. Kelly
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon 97239
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon 97006
| |
Collapse
|
43
|
Qiu J, Wagner EJ, Rønnekleiv OK, Kelly MJ. Insulin and leptin excite anorexigenic pro-opiomelanocortin neurones via activation of TRPC5 channels. J Neuroendocrinol 2018; 30:10.1111/jne.12501. [PMID: 28675783 PMCID: PMC5957276 DOI: 10.1111/jne.12501] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/23/2017] [Accepted: 06/30/2017] [Indexed: 01/03/2023]
Abstract
Pro-opiomelanocortin (POMC) neurones within the hypothalamic arcuate nucleus are vital anorexigenic neurones. Both the insulin receptor and leptin receptor are coupled to activation of phosphatidylinositide-3 kinase (PI3K) to regulate multiple functions that increase POMC neuronal excitability. Using whole-cell recording in several mammalian species, we have found that both insulin and leptin depolarised POMC neurones via activation of transient receptor potential (TRPC)5 channels. TRPC5 channels have been rigorously characterised as the downstream effector based on their biophysical properties, pharmacological profile, and localisation by immunocytochemistry and single-cell reverse transcriptase-polymerase chain reaction. By contrast, insulin and leptin hyperpolarise and inhibit neuropeptide Y/agouti-related peptide neurones via activation of KATP channels. As proof of principle, insulin given i.c.v. robustly inhibits food intake and increases O2 utilisation, CO2 production and metabolic heat production. Therefore, these findings indicate that the depolarisation/excitation of POMC neurones by insulin and leptin is preserved across mammalian species and the activation of TRPC5 channels is likely a major mechanism by which insulin and leptin regulate energy homeostasis in mammals.
Collapse
Affiliation(s)
- J. Qiu
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, USA
| | - E. J. Wagner
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health
Sciences, Pomona, CA, USA
| | - O. K. Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, USA
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University,
Portland, OR, USA
| | - M. J. Kelly
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, USA
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University,
Portland, OR, USA
| |
Collapse
|
44
|
Gao Y, Yao T, Deng Z, Sohn JW, Sun J, Huang Y, Kong X, Yu KJ, Wang RT, Chen H, Guo H, Yan J, Cunningham KA, Chang Y, Liu T, Williams KW. TrpC5 Mediates Acute Leptin and Serotonin Effects via Pomc Neurons. Cell Rep 2017; 18:583-592. [PMID: 28099839 DOI: 10.1016/j.celrep.2016.12.072] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/12/2016] [Accepted: 12/21/2016] [Indexed: 01/28/2023] Open
Abstract
The molecular mechanisms underlying acute leptin and serotonin 2C receptor-induced hypophagia remain unclear. Here, we show that neuronal and pro-opiomelanocortin (Pomc)-specific loss of transient receptor potential cation 5 (TrpC5) subunits is sufficient to decrease energy expenditure and increase food intake resulting in elevated body weight. Deficiency of Trpc5 subunits in Pomc neurons is also sufficient to block the anorexigenic effects of leptin and serotonin 2C receptor (Ht2Cr) agonists. The loss of acute anorexigenic effects of these receptors is concomitant with a blunted electrophysiological response to both leptin and Ht2Cr agonists in arcuate Pomc neurons. We also demonstrate that the Ht2Cr agonist lorcaserin-induced improvements in glucose and insulin tolerance are blocked by TrpC5 deficiency in Pomc neurons. Together, our results link TrpC5 subunits in the brain with leptin- and serotonin 2C receptor-dependent changes in neuronal activity, as well as energy balance, feeding behavior, and glucose metabolism.
Collapse
Affiliation(s)
- Yong Gao
- National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA
| | - Ting Yao
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA
| | - Zhuo Deng
- Department of Gynecology, Shaanxi Provincial People's Hospital, Shaanxi 710000, China; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA
| | - Jong-Woo Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA
| | - Jia Sun
- Department of Endocrinology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA
| | - Yiru Huang
- Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA
| | - Xingxing Kong
- Division of Endocrinology, Beth Israel Deaconess Medical Center and Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Kai-Jiang Yu
- Department of Intensive Care Unit, Third Affiliated Hospital, Harbin Medical University, Nangang District, Harbin, 150081, China
| | - Rui-Tao Wang
- Department of Intensive Care Unit, Third Affiliated Hospital, Harbin Medical University, Nangang District, Harbin, 150081, China
| | - Hong Chen
- Department of Endocrinology, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Hongbo Guo
- Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Jianqun Yan
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Kathryn A Cunningham
- Center for Addiction Research and the Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Yongsheng Chang
- National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.
| | - Tiemin Liu
- Department of Intensive Care Unit, Third Affiliated Hospital, Harbin Medical University, Nangang District, Harbin, 150081, China; Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA.
| | - Kevin W Williams
- Division of Hypothalamic Research, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9077, USA.
| |
Collapse
|
45
|
Garcia-Galiano D, Borges BC, Donato J, Allen SJ, Bellefontaine N, Wang M, Zhao JJ, Kozloff KM, Hill JW, Elias CF. PI3Kα inactivation in leptin receptor cells increases leptin sensitivity but disrupts growth and reproduction. JCI Insight 2017; 2:96728. [PMID: 29212950 DOI: 10.1172/jci.insight.96728] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/23/2017] [Indexed: 12/13/2022] Open
Abstract
The role of PI3K in leptin physiology has been difficult to determine due to its actions downstream of several metabolic cues, including insulin. Here, we used a series of mouse models to dissociate the roles of specific PI3K catalytic subunits and of insulin receptor (InsR) downstream of leptin signaling. We show that disruption of p110α and p110β subunits in leptin receptor cells (LRΔα+β) produces a lean phenotype associated with increased energy expenditure, locomotor activity, and thermogenesis. LRΔα+β mice have deficient growth and delayed puberty. Single subunit deletion (i.e., p110α in LRΔα) resulted in similarly increased energy expenditure, deficient growth, and pubertal development, but LRΔα mice have normal locomotor activity and thermogenesis. Blunted PI3K in leptin receptor (LR) cells enhanced leptin sensitivity in metabolic regulation due to increased basal hypothalamic pAKT, leptin-induced pSTAT3, and decreased PTEN levels. However, these mice are unresponsive to leptin's effects on growth and puberty. We further assessed if these phenotypes were associated with disruption of insulin signaling. LRΔInsR mice have no metabolic or growth deficit and show only mild delay in pubertal completion. Our findings demonstrate that PI3K in LR cells plays an essential role in energy expenditure, growth, and reproduction. These actions are independent from insulin signaling.
Collapse
Affiliation(s)
- David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Beatriz C Borges
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA.,Department of Physiology and
| | - Jose Donato
- Department of Physiology and Biophysics, University of São Paulo, São Paulo, Brazil
| | - Susan J Allen
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicole Bellefontaine
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Mengjie Wang
- Department of Physiology and Pharmacology, University of Toledo, Toledo, Ohio, USA
| | - Jean J Zhao
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Jennifer W Hill
- Department of Physiology and Pharmacology, University of Toledo, Toledo, Ohio, USA
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA.,Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA
| |
Collapse
|
46
|
Dorfman MD, Krull JE, Scarlett JM, Guyenet SJ, Sajan MP, Damian V, Nguyen HT, Leitges M, Morton GJ, Farese RV, Schwartz MW, Thaler JP. Deletion of Protein Kinase C λ in POMC Neurons Predisposes to Diet-Induced Obesity. Diabetes 2017; 66:920-934. [PMID: 28073831 PMCID: PMC5360303 DOI: 10.2337/db16-0482] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 01/02/2017] [Indexed: 12/16/2022]
Abstract
Effectors of the phosphoinositide 3-kinase (PI3K) signal transduction pathway contribute to the hypothalamic regulation of energy and glucose homeostasis in divergent ways. Here we show that central nervous system (CNS) action of the PI3K signaling intermediate atypical protein kinase C (aPKC) constrains food intake, weight gain, and glucose intolerance in both rats and mice. Pharmacological inhibition of CNS aPKC activity acutely increases food intake and worsens glucose tolerance in chow-fed rodents and causes excess weight gain during high-fat diet (HFD) feeding. Similarly, selective deletion of the aPKC isoform Pkc-λ in proopiomelanocortin (POMC) neurons disrupts leptin action, reduces melanocortin content in the paraventricular nucleus, and markedly increases susceptibility to obesity, glucose intolerance, and insulin resistance specifically in HFD-fed male mice. These data implicate aPKC as a novel regulator of energy and glucose homeostasis downstream of the leptin-PI3K pathway in POMC neurons.
Collapse
Affiliation(s)
- Mauricio D Dorfman
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Jordan E Krull
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Jarrad M Scarlett
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Stephan J Guyenet
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Mini P Sajan
- Department of Internal Medicine, University of South Florida College of Medicine, Tampa, FL
- Research & Internal Medicine Services, James A. Haley VA Medical Center, Tampa, FL
| | - Vincent Damian
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Hong T Nguyen
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Michael Leitges
- The Biotechnology Centre of Oslo, University of Oslo, Oslo, Norway
| | - Gregory J Morton
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Robert V Farese
- Department of Internal Medicine, University of South Florida College of Medicine, Tampa, FL
- Research & Internal Medicine Services, James A. Haley VA Medical Center, Tampa, FL
| | - Michael W Schwartz
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| | - Joshua P Thaler
- UW Diabetes Institute and Department of Medicine, University of Washington, Seattle, WA
| |
Collapse
|
47
|
Tups A, Benzler J, Sergi D, Ladyman SR, Williams LM. Central Regulation of Glucose Homeostasis. Compr Physiol 2017; 7:741-764. [DOI: 10.1002/cphy.c160015] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
48
|
Tran DQ, Tse EK, Kim MH, Belsham DD. Diet-induced cellular neuroinflammation in the hypothalamus: Mechanistic insights from investigation of neurons and microglia. Mol Cell Endocrinol 2016; 438:18-26. [PMID: 27208620 DOI: 10.1016/j.mce.2016.05.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 05/17/2016] [Indexed: 12/31/2022]
Abstract
Diet-induced obesity can lead to detrimental chronic disorders. The severity of this global epidemic has encouraged ongoing research to characterize the mechanisms underlying obesity and its comorbidities. Recent evidence suggests that saturated fatty acids (SFA) in high-fat diets rapidly generate inflammation in the arcuate nucleus of the hypothalamus (ARC), which centrally regulates whole-body energy homeostasis. Herein, we will review the roles of hypothalamic neurons and resident microglia in the initiation of SFA-induced hypothalamic inflammation. Particularly, we focus on neuronal and microglial free fatty acid-sensing and capacity to produce inflammatory signaling. We also outline a potential role of peripherally-derived monocytes in this inflammation. And finally, we explore synaptic plasticity as a mechanism through which hypothalamic inflammation can modulate ARC circuitry, and thus disrupt energy homeostasis.
Collapse
Affiliation(s)
- Dean Q Tran
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Erika K Tse
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Mun Heui Kim
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Denise D Belsham
- Department of Physiology, University of Toronto, Toronto, ON, Canada; Department of Obstetrics and Gynaecology, University of Toronto, Toronto, ON, Canada; Department of Medicine, University of Toronto, Toronto, ON, Canada.
| |
Collapse
|
49
|
Endospanin1 affects oppositely body weight regulation and glucose homeostasis by differentially regulating central leptin signaling. Mol Metab 2016; 6:159-172. [PMID: 28123946 PMCID: PMC5220283 DOI: 10.1016/j.molmet.2016.10.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 10/21/2016] [Accepted: 10/27/2016] [Indexed: 01/05/2023] Open
Abstract
The hypothalamic arcuate nucleus (ARC) is a major integration center for energy and glucose homeostasis that responds to leptin. Resistance to leptin in the ARC is an important component of the development of obesity and type 2 diabetes. Recently, we showed that Endospanin1 (Endo1) is a negative regulator of the leptin receptor (OBR) that interacts with OBR and retains the receptor inside the cell, leading to a decreased activation of the anorectic STAT3 pathway. Endo1 is up-regulated in the ARC of high fat diet (HFD)-fed mice, and its silencing in the ARC of lean and obese mice prevents and reverses the development of obesity. OBJECTIVE Herein we investigated whether decreased Endo1 expression in the hypothalamic ARC, associated with reduced obesity, could also ameliorate glucose homeostasis accordingly. METHODS We studied glucose homeostasis in lean or obese mice silenced for Endo1 in the ARC via stereotactic injection of shRNA-expressing lentiviral vectors. RESULTS We observed that despite being leaner, Endo1-silenced mice showed impaired glucose homeostasis on HFD. Mechanistically, we show that Endo1 interacts with p85, the regulatory subunit of PI3K, and mediates leptin-induced PI3K activation. CONCLUSIONS Our results thus define Endo1 as an important hypothalamic integrator of leptin signaling, and its silencing differentially regulates the OBR-dependent functions.
Collapse
Key Words
- ARC, arcuate nucleus
- BW, body weight
- CD, chow diet
- DIO, diet-induced obesity
- Diabetes
- Endo1, Endospanin1
- GTT, glucose tolerance test
- HFD, high fat diet
- Insulin
- LIF, leukemia inhibitory factor
- Leptin receptor
- OB-RGRP/Endospanin1
- OBR, leptin receptor
- Obesity
- PLA, proximity ligation assay
- T2D, type 2 diabetes
- ip, intraperitoneal
Collapse
|
50
|
Singh P, Dar MS, Dar MJ. p110α and p110β isoforms of PI3K signaling: are they two sides of the same coin? FEBS Lett 2016; 590:3071-82. [PMID: 27552098 DOI: 10.1002/1873-3468.12377] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/20/2016] [Accepted: 08/22/2016] [Indexed: 12/30/2022]
Abstract
Class-1 phosphatidylinositol-3-kinases (PI3Ks) are activated by a variety of extracellular stimuli and have been implicated in a wide range of cellular processes. p110α and p110β are the two most studied isoforms of the class-1A PI3K signaling pathway. Although these two isoforms are ubiquitously expressed and play multiple redundant roles, they also have distinct functions within the cell. More recently, p110α and p110β isoforms have been shown to translocate into the nucleus and play a role in DNA replication and repair, and in cell cycle progression. In the following Review article, we discuss the overlapping and unique roles of p110α and p110β isoforms with a particular focus on their structure, expression analysis, subcellular localization, and signaling contributions in various cell types and model organisms.
Collapse
Affiliation(s)
- Paramjeet Singh
- Academy of Scientific and Innovative Research, New Delhi, India.,Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India
| | - Mohd Saleem Dar
- Academy of Scientific and Innovative Research, New Delhi, India.,Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India
| | - Mohd Jamal Dar
- Academy of Scientific and Innovative Research, New Delhi, India. .,Cancer Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India.
| |
Collapse
|