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Anazco D, Ghusn W, Campos A, Cifuentes L, Fansa S, Tama E, Bublitz JT, Gala K, Hurtado MD, Olson JE, Acosta A. Type 2 Diabetes Remission in Patients with Heterozygous Variants in the Leptin-Melanocortin Pathway after Roux-en-Y Gastric Bypass: A Matched Case-Control Study. Obes Surg 2023; 33:3502-3509. [PMID: 37798511 DOI: 10.1007/s11695-023-06859-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/13/2023] [Accepted: 09/24/2023] [Indexed: 10/07/2023]
Abstract
BACKGROUND Roux-en-Y gastric bypass (RYGB) is associated with a high rate of type 2 diabetes (T2D) remission. Carriers of heterozygous variants in the leptin-melanocortin pathway (LMP) are more likely to experience weight recurrence after RYGB. Our aim was to investigate if carrier status and associated weight regain affects the rate of T2D remission after RYGB. METHODS Carriers of LMP variants with a diagnosis of T2D prior to RYGB (N = 16) were matched to non-carriers (N = 32) based on sex, age, and BMI. We assessed for post-operative T2D remission status post-surgery on a yearly basis, for up to 15 years. Our primary endpoint was the proportion of patients achieving T2D remission at 1 year. We conducted a survival analysis for all patients that achieved remission at least at one time-point to evaluate for maintenance of T2D remission by using a log-rank test. RESULTS Both carriers and non-carriers had similar baseline and procedural characteristics. The proopiomelanocortin gene in the LMP pathway had the most variants (n = 5, 31%). Carriers had a lower total body weight loss percentage at nadir (28.7% ± 6.9) than non-carriers (33.7% ± 8.8, p = 0.04). The proportion of patients achieving T2D remission at 1 year was 68.8% for carriers and 71.9% for non-carriers (p = 1.0). Survival curves for maintenance of first remission were similar for both groups (p = 0.73), with a median survival of 8 years for both carriers and non-carriers. CONCLUSIONS Despite inferior weight loss outcomes at nadir, carriers had similar T2D remission rates when compared to non-carriers. Weight-independent metabolic benefits of RYGB might contribute to this observation.
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Affiliation(s)
- Diego Anazco
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
| | - Wissam Ghusn
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
| | - Alejandro Campos
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
| | - Lizeth Cifuentes
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
| | - Sima Fansa
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
| | - Elif Tama
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Medicine, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Joshua T Bublitz
- Division of Epidemiology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, 55902, USA
| | - Khushboo Gala
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
| | - Maria D Hurtado
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Medicine, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Janet E Olson
- Division of Epidemiology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, 55902, USA
| | - Andres Acosta
- Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, 200 First St. S.W., Rochester, MN, 55902, USA.
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Deem JD, Faber CL, Morton GJ. AgRP neurons: Regulators of feeding, energy expenditure, and behavior. FEBS J 2021; 289:2362-2381. [PMID: 34469623 DOI: 10.1111/febs.16176] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/30/2021] [Accepted: 08/31/2021] [Indexed: 12/11/2022]
Abstract
Neurons in the hypothalamic arcuate nucleus (ARC) that express agouti-related peptide (AgRP) govern a critical aspect of survival: the drive to eat. Equally important to survival is the timing at which food is consumed-seeking or eating food to alleviate hunger in the face of a more pressing threat, like the risk of predation, is clearly maladaptive. To ensure optimal prioritization of behaviors within a given environment, therefore, AgRP neurons must integrate signals of internal need states with contextual environmental cues. In this state-of-the-art review, we highlight recent advances that extend our understanding of AgRP neurons, including the neural circuits they engage to regulate feeding, energy expenditure, and behavior. We also discuss key findings that illustrate how both classical feedback and anticipatory feedforward signals regulate this neuronal population and how the integration of these signals may be disrupted in states of energy excess. Finally, we examine both technical and conceptual challenges facing the field moving forward.
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Affiliation(s)
- Jennifer D Deem
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA, USA
| | - Chelsea L Faber
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA, USA.,Department of Neurosurgery, Ivy Brain Tumor Center, Barrow Neurological Institute, Phoenix, AZ, USA
| | - Gregory J Morton
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA, USA
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Fan S, Xu Y, Lu Y, Jiang Z, Li H, Morrill JC, Cai J, Wu Q, Xu Y, Xue M, Arenkiel BR, Huang C, Tong Q. A neural basis for brain leptin action on reducing type 1 diabetic hyperglycemia. Nat Commun 2021; 12:2662. [PMID: 33976218 PMCID: PMC8113586 DOI: 10.1038/s41467-021-22940-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/07/2021] [Indexed: 02/07/2023] Open
Abstract
Central leptin action rescues type 1 diabetic (T1D) hyperglycemia; however, the underlying mechanism and the identity of mediating neurons remain elusive. Here, we show that leptin receptor (LepR)-expressing neurons in arcuate (LepRArc) are selectively activated in T1D. Activation of LepRArc neurons, Arc GABAergic (GABAArc) neurons, or arcuate AgRP neurons, is able to reverse the leptin's rescuing effect. Conversely, inhibition of GABAArc neurons, but not AgRP neurons, produces leptin-mimicking rescuing effects. Further, AgRP neuron function is not required for T1D hyperglycemia or leptin's rescuing effects. Finally, T1D LepRArc neurons show defective nutrient sensing and signs of cellular energy deprivation, which are both restored by leptin, whereas nutrient deprivation reverses the leptin action. Our results identify aberrant activation of LepRArc neurons owing to energy deprivation as the neural basis for T1D hyperglycemia and that leptin action is mediated by inhibiting LepRArc neurons through reversing energy deprivation.
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Affiliation(s)
- Shengjie Fan
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Yuanzhong Xu
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Yungang Lu
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Zhiying Jiang
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Hongli Li
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Jessie C Morrill
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
- MD Anderson Cancer Center & UT Health Graduate School for Biomedical Sciences, University of Texas Health Science at Houston, Houston, TX, USA
| | - Jing Cai
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
- MD Anderson Cancer Center & UT Health Graduate School for Biomedical Sciences, University of Texas Health Science at Houston, Houston, TX, USA
| | - Qi Wu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Mingshan Xue
- Department of Neuroscience and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
| | - Benjamin R Arenkiel
- Department of Molecular and Human Genetics and Department of Neuroscience, Baylor College of Medicine, and Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA
| | - Cheng Huang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Qingchun Tong
- Brown Foundation of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA.
- MD Anderson Cancer Center & UT Health Graduate School for Biomedical Sciences, University of Texas Health Science at Houston, Houston, TX, USA.
- Department of Neurobiology and Anatomy of McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA.
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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.
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Affiliation(s)
- Teppei Fujikawa
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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Mesoporous polymer network produced from N-vinylpyrrolidone and triethylene glycol dimethacrylate as potential macromolecularly imprinted material and oligopeptide carrier. MENDELEEV COMMUNICATIONS 2020. [DOI: 10.1016/j.mencom.2020.11.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Derkach K, Zakharova I, Zorina I, Bakhtyukov A, Romanova I, Bayunova L, Shpakov A. The evidence of metabolic-improving effect of metformin in Ay/a mice with genetically-induced melanocortin obesity and the contribution of hypothalamic mechanisms to this effect. PLoS One 2019; 14:e0213779. [PMID: 30870482 PMCID: PMC6417728 DOI: 10.1371/journal.pone.0213779] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 02/19/2019] [Indexed: 12/16/2022] Open
Abstract
In diet-induced obesity, metformin (MF) has weight-lowering effect and improves glucose homeostasis and insulin sensitivity. However, there is no information on the efficiency of MF and the mechanisms of its action in melanocortin-type obesity. We studied the effect of the 10-day treatment with MF at the doses of 200, 400 and 600 mg/kg/day on the food intake and the metabolic and hormonal parameters in female C57Bl/6J (genotype Ay/a) agouti-mice with melanocortin-type obesity, and the influence of MF on the hypothalamic signaling in obese animals at the most effective metabolic dose (600 mg/kg/day). MF treatment led to a decrease in food intake, the body and fat weights, the plasma levels of glucose, insulin and leptin, all increased in agouti-mice, to an improvement of the lipid profile and glucose sensitivity, and to a reduced fatty liver degeneration. In the hypothalamus of obese agouti-mice, the leptin and insulin content was reduced and the expression of the genes encoding leptin receptor (LepR), MC3- and MC4-melanocortin receptors and pro-opiomelanocortin (POMC), the precursor of anorexigenic melanocortin peptides, was increased. The activities of AMP-activated kinase (AMPK) and the transcriptional factor STAT3 were increased, while Akt-kinase activity did not change from control C57Bl/6J (a/a) mice. In the hypothalamus of MF-treated agouti-mice (10 days, 600 mg/kg/day), the leptin and insulin content was restored, Akt-kinase activity was increased, and the activities of AMPK and STAT3 were reduced and did not differ from control mice. In the hypothalamus of MF-treated agouti-mice, the Pomc gene expression was six times higher than in control, while the gene expression for orexigenic neuropeptide Y was decreased by 39%. Thus, we first showed that MF treatment leads to an improvement of metabolic parameters and a decrease of hyperleptinemia and hyperinsulinaemia in genetically-induced melanocortin obesity, and the specific changes in the hypothalamic signaling makes a significant contribution to this effect of MF.
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Affiliation(s)
- Kira Derkach
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Irina Zakharova
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Inna Zorina
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Andrey Bakhtyukov
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Irina Romanova
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Liubov Bayunova
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Alexander Shpakov
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
- * E-mail:
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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.
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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:
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Meek TH, Matsen ME, Faber CL, Samstag CL, Damian V, Nguyen HT, Scarlett JM, Flak JN, Myers MG, Morton GJ. In Uncontrolled Diabetes, Hyperglucagonemia and Ketosis Result From Deficient Leptin Action in the Parabrachial Nucleus. Endocrinology 2018; 159:1585-1594. [PMID: 29438473 PMCID: PMC5939636 DOI: 10.1210/en.2017-03199] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 01/25/2018] [Indexed: 12/17/2022]
Abstract
Growing evidence implicates neurons that project from the lateral parabrachial nucleus (LPBN) to the hypothalamic ventromedial nucleus (VMN) in a neurocircuit that drives counterregulatory responses to hypoglycemia, including increased glucagon secretion. Among LPBN neurons in this circuit is a subset that expresses cholecystokinin (LPBNCCK neurons) and is tonically inhibited by leptin. Because uncontrolled diabetes is associated with both leptin deficiency and hyperglucagonemia, and because intracerebroventricular (ICV) leptin administration reverses both hyperglycemia and hyperglucagonemia in this setting, we hypothesized that deficient leptin inhibition of LPBNCCK neurons drives activation of this LPBN→VMN circuit and thereby results in hyperglucagonemia. Here, we report that although bilateral microinjection of leptin into the LPBN does not ameliorate hyperglycemia in rats with streptozotocin-induced diabetes mellitus (STZ-DM), it does attenuate the associated hyperglucagonemia and ketosis. To determine if LPBN leptin signaling is required for the antidiabetic effect of ICV leptin in STZ-DM, we studied mice in which the leptin receptor was selectively deleted from LPBNCCK neurons. Our findings show that although leptin signaling in these neurons is not required for the potent antidiabetic effect of ICV leptin, it is required for leptin-mediated suppression of diabetic hyperglucagonemia. Taken together, these findings suggest that leptin-mediated effects in animals with uncontrolled diabetes occur through actions involving multiple brain areas, including the LPBN, where leptin acts specifically to inhibit glucagon secretion and associated ketosis.
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Affiliation(s)
- Thomas H Meek
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Miles E Matsen
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Chelsea L Faber
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Colby L Samstag
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Vincent Damian
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Hong T Nguyen
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Jarrad M Scarlett
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
| | - Jonathan N Flak
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Martin G Myers
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Gregory J Morton
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington
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Tam J, Szanda G, Drori A, Liu Z, Cinar R, Kashiwaya Y, Reitman ML, Kunos G. Peripheral cannabinoid-1 receptor blockade restores hypothalamic leptin signaling. Mol Metab 2017; 6:1113-1125. [PMID: 29031713 PMCID: PMC5641628 DOI: 10.1016/j.molmet.2017.06.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 06/14/2017] [Accepted: 06/16/2017] [Indexed: 01/31/2023] Open
Abstract
Objective In visceral obesity, an overactive endocannabinoid/CB1 receptor (CB1R) system promotes increased caloric intake and decreases energy expenditure, which are mitigated by global or peripheral CB1R blockade. In mice with diet-induced obesity (DIO), inhibition of food intake by the peripherally restricted CB1R antagonist JD5037 could be attributed to endogenous leptin due to the rapid reversal of hyperleptinemia that maintains leptin resistance, but the signaling pathway engaged by leptin has remained to be determined. Methods We analyzed the hypothalamic circuitry targeted by leptin following chronic treatment of DIO mice with JD5037. Results Leptin treatment or an increase in endogenous leptin following fasting/refeeding induced STAT3 phosphorylation in neurons in the arcuate nucleus (ARC) in lean and JD5037-treated DIO mice, but not in vehicle-treated DIO animals. Co-localization of pSTAT3 in leptin-treated mice was significantly less common with NPY+ than with POMC+ ARC neurons. The hypophagic effect of JD5037 was absent in melanocortin-4 receptor (MC4R) deficient obese mice or DIO mice treated with a MC4R antagonist, but was maintained in NPY−/− mice kept on a high-fat diet. Conclusions Peripheral CB1R blockade in DIO restores sensitivity to endogenous leptin, which elicits hypophagia via the re-activation of melanocortin signaling in the ARC. High-fat diet-induced leptin resistance is reversed by peripheral CB1 blockade. Restored leptin signaling by peripheral CB1 blockade occurs via POMC/MC4R pathway. AgRP/NPY neurons are not required for peripheral CB1 blockade-induced hypophagia in mice with diet-induced obesity.
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Affiliation(s)
- Joseph Tam
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel.
| | - Gergő Szanda
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, USA
| | - Adi Drori
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel
| | - Ziyi Liu
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, USA
| | - Resat Cinar
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, USA
| | - Yoshihiro Kashiwaya
- Laboratory of Metabolic Control, National Institute on Alcohol Abuse and Alcoholism, USA
| | - Marc L Reitman
- Diabetes, Endocrinology and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - George Kunos
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, USA.
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Al Sheikh MH. The Determinants of Leptin Levels in Diabetic and Nondiabetic Saudi Males. Int J Endocrinol 2017; 2017:3506871. [PMID: 28348585 PMCID: PMC5350535 DOI: 10.1155/2017/3506871] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/28/2016] [Accepted: 12/20/2016] [Indexed: 12/14/2022] Open
Abstract
Objective. This study aimed to identify the main determinants of serum leptin levels. Methods. A sample of 113 Saudi adult males (55 diabetic and 58 nondiabetic) was selected according to the inclusion and exclusion criteria identified below. Blood samples were taken from participants after fasting for 12 hours. For diabetic patients, the insulin dose was given 12 hours before. In general, the study instrument consisted of blood biochemical tests. Metabolic parameters, glycosylated hemoglobin (HbA1c), low-density lipoprotein (LDL), high-density lipoprotein (HDL), cholesterol, and triglyceride (TG), and adipokines, leptin, adiponectin, visfatin, and resistin, were measured. Multivariate model was utilized to identify the relationship between leptin levels and the independent variables. Results. When adjusted for resistin in the diabetic group, the results demonstrated a significant relationship between visfatin, LDL and TG, and leptin levels (p < 0.05). However, when controlled for resistin, the effect of LDL and TG disappeared while that of visfatin stayed in the model. For the nondiabetic group, the results indicated a significant relationship between insulin, BMI, and leptin levels when adjusted for resistin (p < 0.05). However, the effect of insulin disappeared when the model was controlled for resistin. The study results found no relationship between leptin and adiponectin levels in either the diabetic or nondiabetic group and whether adjusted or controlled for resistin. Conclusion. This study provided better understanding of the metabolism of leptin and unveiled the major determinants of leptin levels in diabetic and nondiabetic males. In conclusion, these results show that the association between leptin and metabolic parameters decreases with the progress of disease.
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Affiliation(s)
- Mona Hmoud Al Sheikh
- Department of Physiology, College of Medicine, University of Dammam, Dammam, Saudi Arabia
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11
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Xu Y, Tong Q. Central leptin action on euglycemia restoration in type 1 diabetes: Restraining responses normally induced by fasting? Int J Biochem Cell Biol 2016; 88:198-203. [PMID: 27702650 DOI: 10.1016/j.biocel.2016.09.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/27/2016] [Accepted: 09/30/2016] [Indexed: 01/29/2023]
Abstract
Leptin monotherapy is sufficient to restore euglycemia in insulinopenic type 1 diabetes (T1D), yet the underlying mechanism remains poorly understood. Accumulating evidence demonstrates that the brain mediates the leptin action on euglycemia restoration. Here, we first review evidence supporting that symptoms in T1D resemble an uncontrolled response to fasting. Then, we discuss recent research progress on brain neurons and their neurotransmitters that potentially mediate the leptin action. Finally, peripheral effective pathways, which are normally involved in fasting responses and associated with leptin action on euglycemia restoration in T1D, will also be discussed. This summary complements several previous excellent reviews on this topic (Meek and Morton, 2016; Perry et al., 2016; Fujikawa and Coppari, 2015). A deep understanding of neurocircuitry and the peripheral effective pathways that mediate the leptin action on euglycemia restoration will likely lead to novel targets for an insulin-independent therapeutics against T1D.
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Affiliation(s)
- Yuanzhong Xu
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, United States
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, United States.
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Shpakov AO. The brain leptin signaling system and its functional state in metabolic syndrome and type 2 diabetes mellitus. J EVOL BIOCHEM PHYS+ 2016. [DOI: 10.1134/s0022093016030017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Derkach KV, Sukhov IB, Kuznetsova LA, Buzanakov DM, Shpakov AO. The functional activity of hypothalamic signaling systems in rats with neonatal diabetes mellitus treated with metformin. DOKL BIOCHEM BIOPHYS 2016; 467:95-8. [PMID: 27193707 DOI: 10.1134/s1607672916020058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Indexed: 11/23/2022]
Abstract
The effect of the two-month metformin treatment (200 mg/kg/day) of rats with the neonatal model of type 2 diabetes mellitus on the functional activity of hypothalamic signaling systems was studied. It was shown that metformin treatment restored the sensitivity of hypothalamic adenylyl cyclase signaling system to agonists of the type 4 melanocortin receptor and the type 2 dopamine receptor but did not influence significantly the functions of the insulin signaling system. These data suggest new targets and mechanisms of metformin action in the CNS, which may mediate its restoring effect on energy homeostasis impaired in diabetic pathology.
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Affiliation(s)
- K V Derkach
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Morisa Toreza 44, St. Petersburg, 194223, Russia
| | - I B Sukhov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Morisa Toreza 44, St. Petersburg, 194223, Russia
| | - L A Kuznetsova
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Morisa Toreza 44, St. Petersburg, 194223, Russia
| | - D M Buzanakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Morisa Toreza 44, St. Petersburg, 194223, Russia
| | - A O Shpakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Morisa Toreza 44, St. Petersburg, 194223, Russia.
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Perry RJ, Petersen KF, Shulman GI. Pleotropic effects of leptin to reverse insulin resistance and diabetic ketoacidosis. Diabetologia 2016; 59:933-7. [PMID: 26961503 PMCID: PMC4826798 DOI: 10.1007/s00125-016-3909-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Accepted: 02/03/2016] [Indexed: 02/07/2023]
Abstract
In this review we discuss the mechanisms for the pleotropic effects of leptin replacement therapy to reverse liver and muscle insulin resistance in lipodystrophic individuals, as well as insulin-independent effects of leptin replacement therapy to suppress white adipose tissue lipolysis, hepatic gluconeogenesis and fasting hyperglycaemia in rodent models of poorly controlled diabetes. On the basis of these studies we conclude with a view of the potential therapeutic applications of leptin replacement therapy in humans. This review summarises a presentation given at the 'Is leptin coming back?' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Thomas Meek and Gregory Morton, DOI: 10.1007/s00125-016-3898-3 , and by Christoffer Clemmensen and colleagues, DOI: 10.1007/s00125-016-3906-7 ) and an overview by the Session Chair, Ulf Smith (DOI: 10.1007/s00125-016-3894-7 ).
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Affiliation(s)
- Rachel J Perry
- Department of Internal Medicine, Yale University School of Medicine, TAC, Room S269, PO Box 208020, New Haven, CT, 06519, USA
| | - Kitt Falk Petersen
- Department of Internal Medicine, Yale University School of Medicine, TAC, Room S269, PO Box 208020, New Haven, CT, 06519, USA
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Gerald I Shulman
- Department of Internal Medicine, Yale University School of Medicine, TAC, Room S269, PO Box 208020, New Haven, CT, 06519, USA.
- Department of Cellular & Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA.
- Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT, USA.
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.
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Abstract
While it is well established that the adiposity hormone leptin plays a key role in the regulation of energy homeostasis, growing evidence suggests that leptin is also critical for glycaemic control. In this review we examine the role of the brain in the glucose-lowering actions of leptin and the potential mediators responsible for driving hyperglycaemia in states of uncontrolled insulin-deficient diabetes (uDM). These considerations highlight the possibility of targeting leptin-sensitive pathways as a therapeutic option for the treatment of diabetes. This review summarises a presentation given at the 'Is leptin coming back?' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Christoffer Clemmensen and colleagues, DOI: 10.1007/s00125-016-3906-7 , and by Gerald Shulman and colleagues, DOI: 10.1007/s00125-016-3909-4 ) and an overview by the Session Chair, Ulf Smith (DOI: 10.1007/s00125-016-3894-7 ).
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Affiliation(s)
- Thomas H Meek
- Diabetes and Obesity Center of Excellence, Department of Medicine, University of Washington at South Lake Union, 850 Republican St., N335, Box 358055, Seattle, WA, 98195, USA
| | - Gregory J Morton
- Diabetes and Obesity Center of Excellence, Department of Medicine, University of Washington at South Lake Union, 850 Republican St., N335, Box 358055, Seattle, WA, 98195, USA.
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Xu Y, Chang JT, Myers MG, Xu Y, Tong Q. Euglycemia Restoration by Central Leptin in Type 1 Diabetes Requires STAT3 Signaling but Not Fast-Acting Neurotransmitter Release. Diabetes 2016; 65:1040-9. [PMID: 26822087 PMCID: PMC4806656 DOI: 10.2337/db15-1160] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 01/13/2016] [Indexed: 12/21/2022]
Abstract
Central leptin action is sufficient to restore euglycemia in insulinopenic type 1 diabetes (T1D); however, the underlying mechanism remains poorly understood. To examine the role of intracellular signal transducer and activator of transcription 3 (STAT3) pathways, we used LepRs/s mice with disrupted leptin-phosphorylated STAT3 signaling to test the effect of central leptin on euglycemia restoration. These mice developed streptozocin-induced T1D, which was surprisingly not associated with hyperglucagonemia, a typical manifestation in T1D. Further, leptin action on euglycemia restoration was abrogated in these mice, which was associated with refractory hypercorticosteronemia. To examine the role of fast-acting neurotransmitters glutamate and γ-aminobutyric acid (GABA), two major neurotransmitters in the brain, from leptin receptor (LepR) neurons, we used mice with disrupted release of glutamate, GABA, or both from LepR neurons. Surprisingly, all mice responded normally to leptin-mediated euglycemia restoration, which was associated with expected correction from hyperglucagonemia and hyperphagia. In contrast, mice with loss of glutamate and GABA appeared to develop an additive obesity effect over those with loss of single neurotransmitter release. Thus, our study reveals that STAT3 signaling, but not fast-acting neurotransmitter release, is required for leptin action on euglycemia restoration and that hyperglucagonemia is not required for T1D.
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Affiliation(s)
- Yuanzhong Xu
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX
| | - Jeffrey T Chang
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX Department of Integrative Biology and Pharmacology of McGovern Medical School and School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX
| | - Martin G Myers
- Departments of Internal Medicine and Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX
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Brain signaling systems in the Type 2 diabetes and metabolic syndrome: promising target to treat and prevent these diseases. Future Sci OA 2015; 1:FSO25. [PMID: 28031898 PMCID: PMC5137856 DOI: 10.4155/fso.15.23] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The changes in the brain signaling systems play an important role in etiology and pathogenesis of Type 2 diabetes mellitus (T2DM) and metabolic syndrome (MS), being a possible cause of these diseases. Therefore, their restoration at the early stages of T2DM and MS can be regarded as a promising way to treat and prevent these diseases and their complications. The data on the functional state of the brain signaling systems regulated by insulin, IGF-1, leptin, dopamine, serotonin, melanocortins and glucagon-like peptide-1, in T2DM and MS, are analyzed. The pharmacological approaches to restoration of these systems and improvement of insulin sensitivity, energy expenditure, lipid metabolism, and to prevent diabetic complications are discussed.
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da Silva AA, Spradley FT, Granger JP, Hall JE, do Carmo JM. Brain-mediated antidiabetic, anorexic, and cardiovascular actions of leptin require melanocortin-4 receptor signaling. J Neurophysiol 2015; 113:2786-91. [PMID: 25717164 DOI: 10.1152/jn.00911.2014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 02/18/2015] [Indexed: 01/19/2023] Open
Abstract
We previously demonstrated that leptin has powerful central nervous system (CNS)-mediated antidiabetic actions. In this study we tested the importance of melanocortin-4 receptors (MC4Rs) for leptin's ability to suppress food intake, increase blood pressure (BP) and heart rate (HR), and normalize glucose levels in insulin-dependent diabetes. MC4R knockout (MC4R-KO) and control wild-type (WT) rats were implanted with intracerebroventricular (ICV) cannula and BP and HR were measured 24 h/day by telemetry. After 5-day control period, an injection of streptozotocin (50 mg/kg, ip) was used to induce diabetes. Eight days after injection, an osmotic pump was implanted subcutaneously and connected to the ICV cannula to deliver leptin (15 μg/day) for 7 days. At baseline, MC4R-KO rats were hyperphagic and 40% heavier than WT rats. Despite obesity, BP was similar (112 ± 2 vs. 111 ± 2 mmHg) and HR was lower in MC4R-KO rats (320 ± 6 vs. 347 ± 5 beats/min). Induction of diabetes increased food intake (30%) and reduced BP (∼17 mmHg) and HR (∼61 beats/min) in WT rats, while food intake, BP, and HR were reduced by ∼10%, 7 mmHg, and 33 beats/min, respectively, in MC4R-KO rats. Leptin treatment normalized blood glucose (437 ± 10 to 136 ± 18 mg/dl), reduced food intake (40%), and increased HR (+60 beats/min) and BP (+9 mmHg) in WT rats. Only modest changes in blood glucose (367 ± 16 to 326 ± 23 mg/dl), food intake (5%), HR (+16 beats/min) and BP (+4 mmHg) were observed in MC4R-KO rats. These results indicate that intact CNS MC4R signaling is necessary for leptin to exert its chronic antidiabetic, anorexic, and cardiovascular actions.
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Affiliation(s)
- Alexandre A da Silva
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Frank T Spradley
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Joey P Granger
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - John E Hall
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Jussara M do Carmo
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi
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Leptin recruits Creb-regulated transcriptional coactivator 1 to improve hyperglycemia in insulin-deficient diabetes. Mol Metab 2014; 4:227-36. [PMID: 25737949 PMCID: PMC4338314 DOI: 10.1016/j.molmet.2014.12.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 12/12/2014] [Accepted: 12/13/2014] [Indexed: 12/31/2022] Open
Abstract
Objective Leptin alleviates hyperglycemia in rodent models of Type 1 diabetes by activating leptin receptors within the central nervous system. Here we delineate whether non-canonical leptin signaling through the Creb-regulated transcriptional coactivator 1 (Crtc1) contributes to leptin-dependent improvements in diabetic glucose metabolism. Methods We employed mice with a targeted genetic disruption of Crtc1, tracer dilution techniques and neuroanatomical studies to interrogate whether Crtc1 enables leptin to improve glucose metabolism in streptozotocin-induced (STZ) diabetes. Results Here we show that leptin improves diabetic glucose metabolism through Crtc1-dependent and independent mechanisms. We find that leptin reduces diabetic hyperglycemia, hepatic gluconeogenic gene expression and selectively increases glucose disposal to brown adipose tissue and heart, in STZ-diabetic Crtc1WT mice but not Crtc1+/− mice. By contrast, leptin decreases circulating glucagon levels in both STZ-diabetic Crtc1WT and Crtc1+/− mice. We also demonstrate that leptin promotes Crtc1 nuclear translocation in pro-opiomelanocortin (Pomc) and non-Pomc neurons within the hypothalamic arcuate nucleus (ARC). Accordingly, leptin's ability to induce Pomc gene expression in the ARC is blunted in STZ-diabetic Crtc1+/− mice. Conclusions Our study reveals that Crtc1 functions as a conduit for leptin's glucoregulatory actions in insulin-dependent diabetes. This study also highlights a new role for Crtc1 in modulating peripheral glucose metabolism.
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