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Beck J, da Silva Teixeira S, Harrison K, Phillips G, He Y, Sisley S. Paraventricular Vitamin D Receptors Are Required for Glucose Tolerance in Males but Not Females. Front Endocrinol (Lausanne) 2022; 13:869678. [PMID: 35620386 PMCID: PMC9128386 DOI: 10.3389/fendo.2022.869678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 03/29/2022] [Indexed: 11/23/2022] Open
Abstract
When delivered directly into the brain, vitamin D, can improve glucose levels in male mice. Additionally, the loss of the vitamin D receptor (VDR) in male mice's paraventricular hypothalamus (PVH) results in impaired glucose tolerance. Data in humans shows that low vitamin D levels are detrimental to glucose homeostasis, an effect that may be more prominent in men. However, it is unknown if vitamin D action in the brain is required for normal glucose regulation in female mice. This study shows that in both viral and genetic models, male mice with obesity and PVH VDR loss have impaired glucose tolerance while female mice are unaffected. Weights were unaltered in both sexes by PVH VDR loss. Additionally, PVH VDR loss did not cause any glucose abnormalities in either sex when the mice were on a chow diet. Utilizing electrophysiology studies, we show PVH VDR loss resulted in decreased baseline firing frequency and resting membrane potential in males, but not females. Additionally, male mice with PVH VDR loss had impaired miniature excitatory postsynaptic currents (mEPSC), while females were unaffected. Interestingly, the PVH neurons of both sexes were activated by exogenous vitamin D (1,25-dihydroxyvitamin D3), an effect dependent upon the VDR. Thus, there is sexual dimorphism, for the actions of the PVH VDR on glucose regulation. PVH VDRs are necessary for normal glucose homeostasis in males but not females and this may be secondary to actions of the VDR on neuronal activity.
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Affiliation(s)
- Jessie Beck
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
- Children’s Nutrition Research Center, Houston, TX, United States
| | - Silvania da Silva Teixeira
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
- Children’s Nutrition Research Center, Houston, TX, United States
| | - Keisha Harrison
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
- Children’s Nutrition Research Center, Houston, TX, United States
| | - Gabrielle Phillips
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
- Children’s Nutrition Research Center, Houston, TX, United States
| | - Yanlin He
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
- Children’s Nutrition Research Center, Houston, TX, United States
- Pennington Biomedical Research Center, Brain Glycemic and Metabolism Control Department, Louisiana State University, Baton Rouge, LA, United States
| | - Stephanie Sisley
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
- Children’s Nutrition Research Center, Houston, TX, United States
- *Correspondence: Stephanie Sisley,
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Mitchell CS, Begg DP. The regulation of food intake by insulin in the central nervous system. J Neuroendocrinol 2021; 33:e12952. [PMID: 33656205 DOI: 10.1111/jne.12952] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/31/2021] [Accepted: 02/03/2021] [Indexed: 01/02/2023]
Abstract
Food intake and energy expenditure are regulated by peripheral signals providing feedback on nutrient status and adiposity to the central nervous system. One of these signals is the pancreatic hormone, insulin. Unlike peripheral administration of insulin, which often causes weight gain, central administration of insulin leads to a reduction in food intake and body weight when administered long-term. This is a result of feedback processes in regions of the brain that regulate food intake. Within the hypothalamus, the arcuate nucleus (ARC) contains subpopulations of neurones that produce orexinergic neuropeptides agouti-related peptide (AgRP)/neuropeptide Y (NPY) and anorexigenic neuropeptides, pro-opiomelanocortin (POMC)/cocaine- and amphetamine-regulated transcript (CART). Intracerebroventricular infusion of insulin down-regulates the expression of AgRP/NPY at the same time as up-regulating expression of POMC/CART. Recent evidence suggests that insulin activity within the amygdala may play an important role in regulating energy balance. Insulin infusion into the central nucleus of the amygdala (CeA) can decrease food intake, possibly by modulating activity of NPY and other neurone subpopulations. Insulin signalling within the CeA can also influence stress-induced obesity. Overall, it is evident that the CeA is a critical target for insulin signalling and the regulation of energy balance.
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Affiliation(s)
| | - Denovan P Begg
- School of Psychology, UNSW Sydney, Sydney, NSW, Australia
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Areias MFC, Prada PO. Mechanisms of insulin resistance in the amygdala: Influences on food intake. Behav Brain Res 2015; 282:209-17. [DOI: 10.1016/j.bbr.2015.01.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/31/2014] [Accepted: 01/05/2015] [Indexed: 12/17/2022]
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The effect of high fat diet and saturated fatty acids on insulin signaling in the amygdala and hypothalamus of rats. Brain Res 2013; 1537:191-200. [DOI: 10.1016/j.brainres.2013.09.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 09/13/2013] [Accepted: 09/19/2013] [Indexed: 12/22/2022]
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Diepenbroek C, Serlie MJ, Fliers E, Kalsbeek A, la Fleur SE. Brain areas and pathways in the regulation of glucose metabolism. Biofactors 2013; 39:505-13. [PMID: 23913677 DOI: 10.1002/biof.1123] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 05/28/2013] [Indexed: 11/11/2022]
Abstract
Glucose is the most important source of fuel for the brain and its concentration must be kept within strict boundaries to ensure the organism's optimal fitness. To maintain glucose homeostasis, an optimal balance between glucose uptake and glucose output is required. Besides managing acute changes in plasma glucose concentrations, the brain controls a daily rhythm in glucose concentrations. The various nuclei within the hypothalamus that are involved in the control of both these processes are well known. However, novel studies indicate an additional role for brain areas that are originally appreciated in other processes than glucose metabolism. Therefore, besides the classic hypothalamic pathways, we will review cortico-limbic brain areas and their role in glucose metabolism.
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Affiliation(s)
- Charlene Diepenbroek
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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