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Basu R, Elmendorf AJ, Lorentz B, Mahler CA, Lazzaro O, App B, Zhou S, Yamamoto Y, Suber M, Wann JC, Roh HC, Sheets PL, Johnson TS, Flak JN. Ventromedial hypothalamic nucleus subset stimulates tissue thermogenesis via preoptic area outputs. Mol Metab 2024; 84:101951. [PMID: 38729241 PMCID: PMC11112375 DOI: 10.1016/j.molmet.2024.101951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 04/20/2024] [Accepted: 04/27/2024] [Indexed: 05/12/2024] Open
Abstract
OBJECTIVE Hypothalamic signals potently stimulate energy expenditure by engaging peripheral mechanisms to restore energy homeostasis. Previous studies have identified several critical hypothalamic sites (e.g. preoptic area (POA) and ventromedial hypothalamic nucleus (VMN)) that could be part of an interconnected neurocircuit that controls tissue thermogenesis and essential for body weight control. However, the key neurocircuit that can stimulate energy expenditure has not yet been established. METHODS Here, we investigated the downstream mechanisms by which VMN neurons stimulate adipose tissue thermogenesis. We manipulated subsets of VMN neurons acutely as well as chronically and studied its effect on tissue thermogenesis and body weight control, using Sf1Cre and Adcyap1Cre mice and measured physiological parameters under both high-fat diet and standard chow diet conditions. To determine the node efferent to these VMN neurons, that is involved in modulating energy expenditure, we employed electrophysiology and optogenetics experiments combined with measurements using tissue-implantable temperature microchips. RESULTS Activation of the VMN neurons that express the steroidogenic factor 1 (Sf1; VMNSf1 neurons) reduced body weight, adiposity and increased energy expenditure in diet-induced obese mice. This function is likely mediated, at least in part, by the release of the pituitary adenylate cyclase-activating polypeptide (PACAP; encoded by the Adcyap1 gene) by the VMN neurons, since we previously demonstrated that PACAP, at the VMN, plays a key role in energy expenditure control. Thus, we then shifted focus to the subpopulation of VMNSf1 neurons that contain the neuropeptide PACAP (VMNPACAP neurons). Since the VMN neurons do not directly project to the peripheral tissues, we traced the location of the VMNPACAP neurons' efferents. We identified that VMNPACAP neurons project to and activate neurons in the caudal regions of the POA whereby these projections stimulate tissue thermogenesis in brown and beige adipose tissue. We demonstrated that selective activation of caudal POA projections from VMNPACAP neurons induces tissue thermogenesis, most potently in negative energy balance and activating these projections lead to some similar, but mostly unique, patterns of gene expression in brown and beige tissue. Finally, we demonstrated that the activation of the VMNPACAP neurons' efferents that lie at the caudal POA are necessary for inducing tissue thermogenesis in brown and beige adipose tissue. CONCLUSIONS These data indicate that VMNPACAP connections with the caudal POA neurons impact adipose tissue function and are important for induction of tissue thermogenesis. Our data suggests that the VMNPACAP → caudal POA neurocircuit and its components are critical for controlling energy balance by activating energy expenditure and body weight control.
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Affiliation(s)
- Rashmita Basu
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA; Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Andrew J Elmendorf
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA; Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Betty Lorentz
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Connor A Mahler
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Olivia Lazzaro
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Britany App
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Shudi Zhou
- Department of Medical Neuroscience, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yura Yamamoto
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Mya Suber
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Jamie C Wann
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Hyun Cheol Roh
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Patrick L Sheets
- Department of Medical Neuroscience, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Travis S Johnson
- Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA; Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA; Melvin and Bren Simon Comprehensive Cancer Centre, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jonathan N Flak
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA; Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, USA.
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Stanley S, Devarakonda K, O'Connor R, Jimenez-Gonzalez M, Alvarsson A, Hampton R, Espinoza D, Li R, Shtekler A, Conner K, Bayne M, Garibay D, Martin J, Lehmann V, Wang L, Kenny P. Amygdala-liver signaling orchestrates rapid glycemic responses to stress and drives stress-induced metabolic dysfunction. RESEARCH SQUARE 2024:rs.3.rs-2924278. [PMID: 38585822 PMCID: PMC10996786 DOI: 10.21203/rs.3.rs-2924278/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Behavioral adaptations to environmental threats are crucial for survival and necessitate rapid deployment of energy reserves. The amygdala coordinates behavioral adaptations to threats, but little is known about its involvement in underpinning metabolic adaptations. Here, we show that acute stress activates medial amygdala (MeA) neurons that innervate the ventromedial hypothalamus (MeAVMH neurons), which precipitates hyperglycemia and hypophagia. The glycemic actions of MeAVMH neurons occur independent of adrenal or pancreatic glucoregulatory hormones. Instead, using whole-body virus tracing, we identify a polysynaptic connection from MeA to the liver, which promotes the rapid synthesis of glucose by hepatic gluconeogenesis. Repeated stress exposure disrupts MeA control of blood glucose and appetite, resulting in diabetes-like dysregulation of glucose homeostasis and weight gain. Our findings reveal a novel amygdala-liver axis that regulates rapid glycemic adaptations to stress and links recurrent stress to metabolic dysfunction.
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Deem JD, Tingley D, Watts CA, Ogimoto K, Bryan CL, Phan BAN, Damian V, Bruchas MR, Scarlett JM, Schwartz MW, Morton GJ. High-fat diet feeding disrupts the coupling of thermoregulation to energy homeostasis. Mol Metab 2023; 78:101835. [PMID: 37931788 PMCID: PMC10681932 DOI: 10.1016/j.molmet.2023.101835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/26/2023] [Accepted: 11/02/2023] [Indexed: 11/08/2023] Open
Abstract
OBJECTIVE Preserving core body temperature across a wide range of ambient temperatures requires adaptive changes of thermogenesis that must be offset by corresponding changes of energy intake if body fat stores are also to be preserved. Among neurons implicated in the integration of thermoregulation with energy homeostasis are those that express both neuropeptide Y (NPY) and agouti-related protein (AgRP) (referred to herein as AgRP neurons). Specifically, cold-induced activation of AgRP neurons was recently shown to be required for cold exposure to increase food intake in mice. Here, we investigated how consuming a high-fat diet (HFD) impacts various adaptive responses to cold exposure as well as the responsiveness of AgRP neurons to cold. METHODS To test this, we used immunohistochemistry, in vivo fiber photometry and indirect calorimetry for continuous measures of core temperature, energy expenditure, and energy intake in both chow- and HFD-fed mice housed at different ambient temperatures. RESULTS We show that while both core temperature and the thermogenic response to cold are maintained normally in HFD-fed mice, the increase of energy intake needed to preserve body fat stores is blunted, resulting in weight loss. Using both immunohistochemistry and in vivo fiber photometry, we show that although cold-induced AgRP neuron activation is detected regardless of diet, the number of cold-responsive neurons appears to be blunted in HFD-fed mice. CONCLUSIONS We conclude that HFD-feeding disrupts the integration of systems governing thermoregulation and energy homeostasis that protect body fat mass during cold exposure.
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Affiliation(s)
- Jennifer D Deem
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - David Tingley
- Beth Israel-Deaconess Medical Center, Harvard University, School of Medicine, Boston, MA, USA
| | - Christina A Watts
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - Kayoko Ogimoto
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - Caeley L Bryan
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - Bao Anh N Phan
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - Vincent Damian
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - Michael R Bruchas
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, USA; Department of Pharmacology, University of Washington, Seattle, WA, USA; Center for the Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA, USA
| | - Jarrad M Scarlett
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA; Department of Pediatric Gastroenterology and Hepatology, Seattle Children's Hospital, Seattle, WA, USA
| | - Michael W Schwartz
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA
| | - Gregory J Morton
- University of Washington Medicine Diabetes Institute, Department of Medicine, Seattle, WA, USA.
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Chambers ME, Nuibe EH, Reno-Bernstein CM. Brain Regulation of Cardiac Function during Hypoglycemia. Metabolites 2023; 13:1089. [PMID: 37887414 PMCID: PMC10608630 DOI: 10.3390/metabo13101089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/02/2023] [Accepted: 10/16/2023] [Indexed: 10/28/2023] Open
Abstract
Hypoglycemia occurs frequently in people with type 1 and type 2 diabetes. Hypoglycemia activates the counter-regulatory response. Besides peripheral glucose sensors located in the pancreas, mouth, gastrointestinal tract, portal vein, and carotid body, many brain regions also contain glucose-sensing neurons that detect this fall in glucose. The autonomic nervous system innervates the heart, and during hypoglycemia, can cause many changes. Clinical and animal studies have revealed changes in electrocardiograms during hypoglycemia. Cardiac repolarization defects (QTc prolongation) occur during moderate levels of hypoglycemia. When hypoglycemia is severe, it can be fatal. Cardiac arrhythmias are thought to be the major mediator of sudden death due to severe hypoglycemia. Both the sympathetic and parasympathetic nervous systems of the brain have been implicated in regulating these arrhythmias. Besides cardiac arrhythmias, hypoglycemia can have profound changes in the heart and most of these changes are exacerbated in the setting of diabetes. A better understanding of how the brain regulates cardiac changes during hypoglycemia will allow for better therapeutic intervention to prevent cardiovascular death associated with hypoglycemia in people with diabetes. The aim of this paper is to provide a narrative review of what is known in the field regarding how the brain regulates the heart during hypoglycemia.
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Affiliation(s)
| | | | - Candace M. Reno-Bernstein
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA (E.H.N.)
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Zhu KW, Tao GJ, Huang ZL, Qu WM, Wang L. Whole-brain connectivity to the bed nucleus of the stria terminalis calretinin-expressing interneurons in male mice. Eur J Neurosci 2023; 58:2807-2823. [PMID: 37452644 DOI: 10.1111/ejn.16068] [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: 03/10/2023] [Revised: 05/16/2023] [Accepted: 06/08/2023] [Indexed: 07/18/2023]
Abstract
The bed nucleus of the stria terminalis (BNST) is a neuropeptide-enriched brain region that modulates a wide variety of emotional behaviours and states, including stress, anxiety, reward and social interaction. The BNST consists of diverse subregions and neuronal ensembles; however, because of the high molecular heterogeneity within BNST neurons, the mechanisms through which the BNST regulates distinct emotional behaviours remain largely unclear. Prior studies have identified BNST calretinin (CR)-expressing neurons, which lack neuropeptides. Here, employing virus-based cell-type-specific retrograde and anterograde tracing systems, we mapped the whole-brain monosynaptic inputs and axonal projections of BNST CR-expressing neurons in male mice. We found that BNST CR-expressing neurons received inputs mainly from the amygdalopiriform transition area, central amygdala and hippocampus and moderately from the medial preoptic area, basolateral amygdala, paraventricular thalamus and lateral hypothalamus. Within the BNST, plenty of input neurons were primarily located in the oval and interfascicular subregions. Furthermore, numerous BNST CR-expressing neuronal boutons were observed within the BNST but not in other brain regions, thus suggesting that these neurons are a type of interneuron. These results will help further elucidate the neuronal circuits underlying the elaborate and distinct functions of the BNST.
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Affiliation(s)
- Ke-Wei Zhu
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Gui-Jin Tao
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Zhi-Li Huang
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Wei-Min Qu
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Lu Wang
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
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Tu L, Bean JC, He Y, Liu H, Yu M, Liu H, Zhang N, Yin N, Han J, Scarcelli NA, Conde KM, Wang M, Li Y, Feng B, Gao P, Cai ZL, Fukuda M, Xue M, Tong Q, Yang Y, Liao L, Xu J, Wang C, He Y, Xu Y. Anoctamin 4 channel currents activate glucose-inhibited neurons in the mouse ventromedial hypothalamus during hypoglycemia. J Clin Invest 2023; 133:e163391. [PMID: 37261917 PMCID: PMC10348766 DOI: 10.1172/jci163391] [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: 07/07/2022] [Accepted: 05/30/2023] [Indexed: 06/03/2023] Open
Abstract
Glucose is the basic fuel essential for maintenance of viability and functionality of all cells. However, some neurons - namely, glucose-inhibited (GI) neurons - paradoxically increase their firing activity in low-glucose conditions and decrease that activity in high-glucose conditions. The ionic mechanisms mediating electric responses of GI neurons to glucose fluctuations remain unclear. Here, we showed that currents mediated by the anoctamin 4 (Ano4) channel are only detected in GI neurons in the ventromedial hypothalamic nucleus (VMH) and are functionally required for their activation in response to low glucose. Genetic disruption of the Ano4 gene in VMH neurons reduced blood glucose and impaired counterregulatory responses during hypoglycemia in mice. Activation of VMHAno4 neurons increased food intake and blood glucose, while chronic inhibition of VMHAno4 neurons ameliorated hyperglycemia in a type 1 diabetic mouse model. Finally, we showed that VMHAno4 neurons represent a unique orexigenic VMH population and transmit a positive valence, while stimulation of neurons that do not express Ano4 in the VMH (VMHnon-Ano4) suppress feeding and transmit a negative valence. Together, our results indicate that the Ano4 channel and VMHAno4 neurons are potential therapeutic targets for human diseases with abnormal feeding behavior or glucose imbalance.
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Affiliation(s)
- Longlong Tu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Jonathan C. Bean
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Yang He
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Hailan Liu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Meng Yu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Hesong Liu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Nan Zhang
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Na Yin
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Junying Han
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Nikolas A. Scarcelli
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Kristine M. Conde
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Mengjie Wang
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Yongxiang Li
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Bing Feng
- Brain glycemic and metabolism control department, Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Peiyu Gao
- Brain glycemic and metabolism control department, Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Zhao-Lin Cai
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, USA
| | - Makoto Fukuda
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Mingshan Xue
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, USA
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Yongjie Yang
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Lan Liao
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Jianming Xu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Chunmei Wang
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Yanlin He
- Brain glycemic and metabolism control department, Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Yong Xu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
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Makrygianni EA, Chrousos GP. Neural Progenitor Cells and the Hypothalamus. Cells 2023; 12:1822. [PMID: 37508487 PMCID: PMC10378393 DOI: 10.3390/cells12141822] [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: 03/02/2023] [Revised: 05/22/2023] [Accepted: 06/02/2023] [Indexed: 07/30/2023] Open
Abstract
Neural progenitor cells (NPCs) are multipotent neural stem cells (NSCs) capable of self-renewing and differentiating into neurons, astrocytes and oligodendrocytes. In the postnatal/adult brain, NPCs are primarily located in the subventricular zone (SVZ) of the lateral ventricles (LVs) and subgranular zone (SGZ) of the hippocampal dentate gyrus (DG). There is evidence that NPCs are also present in the postnatal/adult hypothalamus, a highly conserved brain region involved in the regulation of core homeostatic processes, such as feeding, metabolism, reproduction, neuroendocrine integration and autonomic output. In the rodent postnatal/adult hypothalamus, NPCs mainly comprise different subtypes of tanycytes lining the wall of the 3rd ventricle. In the postnatal/adult human hypothalamus, the neurogenic niche is constituted by tanycytes at the floor of the 3rd ventricle, ependymal cells and ribbon cells (showing a gap-and-ribbon organization similar to that in the SVZ), as well as suprachiasmatic cells. We speculate that in the postnatal/adult human hypothalamus, neurogenesis occurs in a highly complex, exquisitely sophisticated neurogenic niche consisting of at least four subniches; this structure has a key role in the regulation of extrahypothalamic neurogenesis, and hypothalamic and extrahypothalamic neural circuits, partly through the release of neurotransmitters, neuropeptides, extracellular vesicles (EVs) and non-coding RNAs (ncRNAs).
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Affiliation(s)
- Evanthia A Makrygianni
- University Research Institute of Maternal and Child Health & Precision Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - George P Chrousos
- University Research Institute of Maternal and Child Health & Precision Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece
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Deem JD, Phan BA, Ogimoto K, Cheng A, Bryan CL, Scarlett JM, Schwartz MW, Morton GJ. Warm Responsive Neurons in the Hypothalamic Preoptic Area are Potent Regulators of Glucose Homeostasis in Male Mice. Endocrinology 2023; 164:bqad074. [PMID: 37279930 PMCID: PMC10653198 DOI: 10.1210/endocr/bqad074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/02/2023] [Accepted: 06/05/2023] [Indexed: 06/08/2023]
Abstract
When mammals are exposed to a warm environment, overheating is prevented by activation of "warm-responsive" neurons (WRNs) in the hypothalamic preoptic area (POA) that reduce thermogenesis while promoting heat dissipation. Heat exposure also impairs glucose tolerance, but whether this also results from activation of POA WRNs is unknown. To address this question, we sought in the current work to determine if glucose intolerance induced by heat exposure can be attributed to activation of a specific subset of WRNs that express pituitary adenylate cyclase-activating peptide (ie, POAPacap neurons). We report that when mice are exposed to an ambient temperature sufficiently warm to activate POAPacap neurons, the expected reduction of energy expenditure is associated with glucose intolerance, and that these responses are recapitulated by chemogenetic POAPacap neuron activation. Because heat-induced glucose intolerance was not blocked by chemogenetic inhibition of POAPacap neurons, we conclude that POAPacap neuron activation is sufficient, but not required, to explain the impairment of glucose tolerance elicited by heat exposure.
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Affiliation(s)
- Jennifer D Deem
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
| | - Bao Anh Phan
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
| | - Kayoko Ogimoto
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
| | - Alice Cheng
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
| | - Caeley L Bryan
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
| | - Jarrad M Scarlett
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
- Department of Pediatric Gastroenterology and Hepatology, Seattle Children's Hospital, Seattle, WA 98145, USA
| | - Michael W Schwartz
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
| | - Gregory J Morton
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA 98109, USA
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Cai CY, Tao Y, Zhou Y, Yang D, Qin C, Bian XL, Xian JY, Cao B, Chang L, Wu HY, Luo CX, Zhu DY. Nos1 + and Nos1 - excitatory neurons in the BLA regulate anxiety- and depression-related behaviors oppositely. J Affect Disord 2023; 333:181-192. [PMID: 37080493 DOI: 10.1016/j.jad.2023.04.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/31/2023] [Accepted: 04/14/2023] [Indexed: 04/22/2023]
Abstract
BACKGROUND The basolateral amygdala (BLA) neurons are primarily glutamatergic and have been associated with emotion regulation. However, little is known about the roles of BLA neurons expressing neuronal nitric oxide synthase (nNOS, Nos1) in the regulation of emotional behaviors. METHODS Using Nos1-cre mice and chemogenetic and optogenetic manipulations, we specifically silenced or activated Nos1+ or Nos1- neurons in the BLA, or silenced their projections to the anterdorsal bed nucleus of the stria terminalis (adBNST) and ventral hippocampus (vHPC). We measured anxiety behaviors in elevated plus maze (EPM) and open-field test (OFT), and measured depression behaviors in forced swimming test (FST) and tail suspension test (TST). RESULTS BLA Nos1+ neurons were predominantly glutamatergic, and glutamatergic but not GABAergic Nos1+ neurons were involved in controlling anxiety- and depression-related behaviors. Interestingly, by selectively manipulating the activities of BLA Nos1+ and Nos1- excitatory neurons, we found that they had opposing effects on anxiety- and depression-related behaviors. BLA Nos1+ excitatory neurons projected to the adBNST, this BLA-adBNST circuit controlled the expression of anxiety- and depression-related behaviors, while BLA Nos1- excitatory neurons projected to vHPC, this BLA-vHPC circuit contributed to the expression of anxiety- and depression-related behaviors. Moreover, excitatory vHPC-adBNST circuit antagonized the role of BLA-adBNST circuit in regulating anxiety- and depression-related behaviors. CONCLUSIONS BLA Nos1+ and Nos1- excitatory neuron subpopulations exert different effects on anxiety- and depression-related behaviors through distinct projection circuits, providing a new insight of BLA excitatory neurons in emotional regulation. LIMITATIONS We did not perform retrograde labeling from adBNST and vHPC regions.
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Affiliation(s)
- Cheng-Yun Cai
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Yan Tao
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Ying Zhou
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Di Yang
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Cheng Qin
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Xin-Lan Bian
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Jia-Yun Xian
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Bo Cao
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Lei Chang
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Hai-Yin Wu
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Chun-Xia Luo
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Dong-Ya Zhu
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China; Institution of Stem Cells and Neuroregeneration, Nanjing Medical University, Nanjing 211166, China; Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangzhou, China.
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Schwartz MW, Krinsley JS, Faber CL, Hirsch IB, Brownlee M. Brain Glucose Sensing and the Problem of Relative Hypoglycemia. Diabetes Care 2023; 46:237-244. [PMID: 36701597 PMCID: PMC9887623 DOI: 10.2337/dc22-1445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 11/22/2022] [Indexed: 01/27/2023]
Abstract
"Relative hypoglycemia" is an often-overlooked complication of diabetes characterized by an increase in the glycemic threshold for detecting and responding to hypoglycemia. The clinical relevance of this problem is linked to growing evidence that among patients with critical illness, higher blood glucose in the intensive care unit is associated with higher mortality among patients without diabetes but lower mortality in patients with preexisting diabetes and an elevated prehospitalization HbA1c. Although additional studies are needed, the cardiovascular stress associated with hypoglycemia perception, which can occur at normal or even elevated glucose levels in patients with diabetes, offers a plausible explanation for this difference in outcomes. Little is known, however, regarding how hypoglycemia is normally detected by the brain, much less how relative hypoglycemia develops in patients with diabetes. In this article, we explore the role in hypoglycemia detection played by glucose-responsive sensory neurons supplying peripheral vascular beds and/or circumventricular organs. These observations support a model wherein relative hypoglycemia results from diabetes-associated impairment of this neuronal glucose-sensing process. By raising the glycemic threshold for hypoglycemia perception, this impairment may contribute to the increased mortality risk associated with standard glycemic management of critically ill patients with diabetes.
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Affiliation(s)
- Michael W. Schwartz
- Department of Medicine, University of Washington Medicine Diabetes Institute, Seattle, WA
| | - James S. Krinsley
- Stamford Hospital, Stamford, CT
- Columbia Vagelos College of Physicians and Surgeons, New York, NY
| | - Chelsea L. Faber
- Ivy Brain Tumor Center, Department of Neurosurgery, Barrow Neurological Institute, Phoenix, AZ
| | - Irl B. Hirsch
- Department of Medicine, University of Washington Medicine Diabetes Institute, Seattle, WA
| | - Michael Brownlee
- Einstein Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY
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11
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Martinez-Sanchez N, Sweeney O, Sidarta-Oliveira D, Caron A, Stanley SA, Domingos AI. The sympathetic nervous system in the 21st century: Neuroimmune interactions in metabolic homeostasis and obesity. Neuron 2022; 110:3597-3626. [PMID: 36327900 PMCID: PMC9986959 DOI: 10.1016/j.neuron.2022.10.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 08/23/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022]
Abstract
The sympathetic nervous system maintains metabolic homeostasis by orchestrating the activity of organs such as the pancreas, liver, and white and brown adipose tissues. From the first renderings by Thomas Willis to contemporary techniques for visualization, tracing, and functional probing of axonal arborizations within organs, our understanding of the sympathetic nervous system has started to grow beyond classical models. In the present review, we outline the evolution of these findings and provide updated neuroanatomical maps of sympathetic innervation. We offer an autonomic framework for the neuroendocrine loop of leptin action, and we discuss the role of immune cells in regulating sympathetic terminals and metabolism. We highlight potential anti-obesity therapeutic approaches that emerge from the modern appreciation of SNS as a neural network vis a vis the historical fear of sympathomimetic pharmacology, while shifting focus from post- to pre-synaptic targeting. Finally, we critically appraise the field and where it needs to go.
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Affiliation(s)
| | - Owen Sweeney
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Davi Sidarta-Oliveira
- Physician-Scientist Graduate Program, Obesity and Comorbidities Research Center, School of Medical Sciences, University of Campinas, Campinas, Brazil
| | - Alexandre Caron
- Faculty of Pharmacy, Université Laval, Québec City, QC G1V 0A6, Canada
| | - Sarah A Stanley
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ana I Domingos
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK.
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12
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Jia X, Chen S, Li X, Tao S, Lai J, Liu H, Huang K, Tian Y, Wei P, Yang F, Lu Z, Chen Z, Liu XA, Xu F, Wang L. Divergent neurocircuitry dissociates two components of the stress response: glucose mobilization and anxiety-like behavior. Cell Rep 2022; 41:111586. [DOI: 10.1016/j.celrep.2022.111586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/19/2022] [Accepted: 10/07/2022] [Indexed: 11/09/2022] Open
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13
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Rawlinson S, Reichenbach A, Clarke RE, Nuñez-Iglesias J, Dempsey H, Lockie SH, Andrews ZB. In Vivo Photometry Reveals Insulin and 2-Deoxyglucose Maintain Prolonged Inhibition of VMH Vglut2 Neurons in Male Mice. Endocrinology 2022; 163:6631280. [PMID: 35788848 DOI: 10.1210/endocr/bqac095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Indexed: 11/19/2022]
Abstract
The ventromedial hypothalamic (VMH) nucleus is a well-established hub for energy and glucose homeostasis. In particular, VMH neurons are thought to be important for initiating the counterregulatory response to hypoglycemia, and ex vivo electrophysiology and immunohistochemistry data indicate a clear role for VMH neurons in sensing glucose concentration. However, the temporal response of VMH neurons to physiologically relevant changes in glucose availability in vivo has been hampered by a lack of available tools for measuring neuronal activity over time. Since the majority of neurons within the VMH are glutamatergic and can be targeted using the vesicular glutamate transporter Vglut2, we expressed cre-dependent GCaMP7s in Vglut2 cre mice and examined the response profile of VMH to intraperitoneal injections of glucose, insulin, and 2-deoxyglucose (2DG). We show that reduced available glucose via insulin-induced hypoglycemia and 2DG-induced glucoprivation, but not hyperglycemia induced by glucose injection, inhibits VMH Vglut2 neuronal population activity in vivo. Surprisingly, this inhibition was maintained for at least 45 minutes despite prolonged hypoglycemia and initiation of a counterregulatory response. Thus, although VMH stimulation, via pharmacological, electrical, or optogenetic approaches, is sufficient to drive a counterregulatory response, our data suggest VMH Vglut2 neurons are not the main drivers required to do so, since VMH Vglut2 neuronal population activity remains suppressed during hypoglycemia and glucoprivation.
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Affiliation(s)
- Sasha Rawlinson
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, 3800, Australia
| | - Alex Reichenbach
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, 3800, Australia
| | - Rachel E Clarke
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Juan Nuñez-Iglesias
- Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, 3800, Australia
| | - Harry Dempsey
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, 3800, Australia
| | - Sarah H Lockie
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, 3800, Australia
| | - Zane B Andrews
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, 3800, Australia
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14
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SOCS3 Ablation in Leptin Receptor-Expressing Cells Causes Autonomic and Cardiac Dysfunctions in Middle-Aged Mice despite Improving Energy and Glucose Metabolism. Int J Mol Sci 2022; 23:ijms23126484. [PMID: 35742928 PMCID: PMC9223472 DOI: 10.3390/ijms23126484] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 02/04/2023] Open
Abstract
Leptin resistance is a hallmark of obesity. Treatments aiming to improve leptin sensitivity are considered a promising therapeutical approach against obesity. However, leptin receptor (LepR) signaling also modulates several neurovegetative aspects, such as the cardiovascular system and hepatic gluconeogenesis. Thus, we investigated the long-term consequences of increased leptin sensitivity, considering the potential beneficial and deleterious effects. To generate a mouse model with increased leptin sensitivity, the suppressor of cytokine signaling 3 (SOCS3) was ablated in LepR-expressing cells (LepR∆SOCS3 mice). LepR∆SOCS3 mice displayed reduced food intake, body adiposity and weight gain, as well as improved glucose tolerance and insulin sensitivity, and were protected against aging-induced leptin resistance. Surprisingly, a very high mortality rate was observed in aging LepR∆SOCS3 mice. LepR∆SOCS3 mice showed cardiomyocyte hypertrophy, increased myocardial fibrosis and reduced cardiovascular capacity. LepR∆SOCS3 mice exhibited impaired post-ischemic cardiac functional recovery and middle-aged LepR∆SOCS3 mice showed substantial arhythmic events during the post-ischemic reperfusion period. Finally, LepR∆SOCS3 mice exhibited fasting-induced hypoglycemia and impaired counterregulatory response to glucopenia associated with reduced gluconeogenesis. In conclusion, although increased sensitivity to leptin improved the energy and glucose homeostasis of aging LepR∆SOCS3 mice, major autonomic/neurovegetative dysfunctions compromised the health and longevity of these animals. Consequently, these potentially negative aspects need to be considered in the therapies that increase leptin sensitivity chronically.
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15
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Verberne AJM, Mussa BM. Neural control of pancreatic peptide hormone secretion. Peptides 2022; 152:170768. [PMID: 35189258 DOI: 10.1016/j.peptides.2022.170768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/10/2022] [Accepted: 02/12/2022] [Indexed: 11/20/2022]
Abstract
Pancreatic peptide hormone secretion is inextricably linked to maintenance of normal levels of blood glucose. In animals and man, pancreatic peptide hormone secretion is controlled, at least in part, by input from parasympathetic (vagal) premotor neurons that are found principally in the dorsal motor nucleus of the vagus (DMV). Iatrogenic (insulin-induced) hypoglycaemia evokes a homeostatic response commonly referred to as the glucose counter-regulatory response. This homeostatic response is of particular importance in Type 1 diabetes in which episodes of hypoglycaemia are common, debilitating and lead to suboptimal control of blood glucose. Glucagon is the principal counterregulatory hormone but for reasons unknown, its secretion during insulin-induced hypoglycaemia is impaired. Pancreatic parasympathetic neurons are distinguishable electrophysiologically from those that control other (e.g. gastric) functions and are controlled by supramedullary inputs from hypothalamic structures such as the perifornical region. During hypoglycaemia, glucose-sensitive, GABAergic neurons in the ventromedial hypothalamus are inhibited leading to disinhibition of perifornical orexin neurons with projections to the DMV which, in turn, leads to increased secretion of glucagon.
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Affiliation(s)
- Anthony J M Verberne
- Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria 3084, Australia.
| | - Bashair M Mussa
- Basic Medical Science Department, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates
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16
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Tu L, Fukuda M, Tong Q, Xu Y. The ventromedial hypothalamic nucleus: watchdog of whole-body glucose homeostasis. Cell Biosci 2022; 12:71. [PMID: 35619170 PMCID: PMC9134642 DOI: 10.1186/s13578-022-00799-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 04/25/2022] [Indexed: 02/06/2023] Open
Abstract
The brain, particularly the ventromedial hypothalamic nucleus (VMH), has been long known for its involvement in glucose sensing and whole-body glucose homeostasis. However, it is still not fully understood how the brain detects and responds to the changes in the circulating glucose levels, as well as brain-body coordinated control of glucose homeostasis. In this review, we address the growing evidence implicating the brain in glucose homeostasis, especially in the contexts of hypoglycemia and diabetes. In addition to neurons, we emphasize the potential roles played by non-neuronal cells, as well as extracellular matrix in the hypothalamus in whole-body glucose homeostasis. Further, we review the ionic mechanisms by which glucose-sensing neurons sense fluctuations of ambient glucose levels. We also introduce the significant implications of heterogeneous neurons in the VMH upon glucose sensing and whole-body glucose homeostasis, in which sex difference is also addressed. Meanwhile, research gaps have also been identified, which necessities further mechanistic studies in future.
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Affiliation(s)
- Longlong Tu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street #8066, Houston, TX, 77030, USA
| | - Makoto Fukuda
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street #8066, Houston, TX, 77030, USA
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Yong Xu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street #8066, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.
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17
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Mirzadeh Z, Faber CL, Schwartz MW. Central Nervous System Control of Glucose Homeostasis: A Therapeutic Target for Type 2 Diabetes? Annu Rev Pharmacol Toxicol 2022; 62:55-84. [PMID: 34990204 PMCID: PMC8900291 DOI: 10.1146/annurev-pharmtox-052220-010446] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Historically, pancreatic islet beta cells have been viewed as principal regulators of glycemia, with type 2 diabetes (T2D) resulting when insulin secretion fails to compensate for peripheral tissue insulin resistance. However, glycemia is also regulated by insulin-independent mechanisms that are dysregulated in T2D. Based on evidence supporting its role both in adaptive coupling of insulin secretion to changes in insulin sensitivity and in the regulation of insulin-independent glucose disposal, the central nervous system (CNS) has emerged as a fundamental player in glucose homeostasis. Here, we review and expand upon an integrative model wherein the CNS, together with the islet, establishes and maintains the defended level of glycemia. We discuss the implications of this model for understanding both normal glucose homeostasis and T2D pathogenesis and highlight centrally targeted therapeutic approaches with the potential to restore normoglycemia to patients with T2D.
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Affiliation(s)
- Zaman Mirzadeh
- Ivy Brain Tumor Center, Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona 85013, USA;
| | - Chelsea L Faber
- Ivy Brain Tumor Center, Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona 85013, USA;
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington 98109, USA;
| | - Michael W Schwartz
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, Washington 98109, USA;
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18
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Abstract
The ventromedial nucleus of the hypothalamus (VMH) is a complex brain structure that is integral to many neuroendocrine functions, including glucose regulation, thermogenesis, and appetitive, social, and sexual behaviors. As such, it is of little surprise that the nucleus is under intensive investigation to decipher the mechanisms which underlie these diverse roles. Developments in genetic and investigative tools, for example the targeting of steroidogenic factor-1-expressing neurons, have allowed us to take a closer look at the VMH, its connections, and how it affects competing behaviors. In the current review, we aim to integrate recent findings into the literature and contemplate the conclusions that can be drawn.
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Affiliation(s)
- Tansi Khodai
- Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester, UK
| | - Simon M Luckman
- Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester, UK
- Correspondence: Simon M. Luckman, Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester, UK.
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19
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Bozadjieva-Kramer N, Ross RA, Johnson DQ, Fenselau H, Haggerty DL, Atwood B, Lowell B, Flak JN. The Role of Mediobasal Hypothalamic PACAP in the Control of Body Weight and Metabolism. Endocrinology 2021; 162:6103920. [PMID: 33460433 PMCID: PMC7875177 DOI: 10.1210/endocr/bqab012] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Indexed: 12/26/2022]
Abstract
Body energy homeostasis results from balancing energy intake and energy expenditure. Central nervous system administration of pituitary adenylate cyclase activating polypeptide (PACAP) dramatically alters metabolic function, but the physiologic mechanism of this neuropeptide remains poorly defined. PACAP is expressed in the mediobasal hypothalamus (MBH), a brain area essential for energy balance. Ventromedial hypothalamic nucleus (VMN) neurons contain, by far, the largest and most dense population of PACAP in the medial hypothalamus. This region is involved in coordinating the sympathetic nervous system in response to metabolic cues in order to re-establish energy homeostasis. Additionally, the metabolic cue of leptin signaling in the VMN regulates PACAP expression. We hypothesized that PACAP may play a role in the various effector systems of energy homeostasis, and tested its role by using VMN-directed, but MBH encompassing, adeno-associated virus (AAVCre) injections to ablate Adcyap1 (gene coding for PACAP) in mice (Adcyap1MBHKO mice). Adcyap1MBHKO mice rapidly gained body weight and adiposity, becoming hyperinsulinemic and hyperglycemic. Adcyap1MBHKO mice exhibited decreased oxygen consumption (VO2), without changes in activity. These effects appear to be due at least in part to brown adipose tissue (BAT) dysfunction, and we show that PACAP-expressing cells in the MBH can stimulate BAT thermogenesis. While we observed disruption of glucose clearance during hyperinsulinemic/euglycemic clamp studies in obese Adcyap1MBHKO mice, these parameters were normal prior to the onset of obesity. Thus, MBH PACAP plays important roles in the regulation of metabolic rate and energy balance through multiple effector systems on multiple time scales, which highlight the diverse set of functions for PACAP in overall energy homeostasis.
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Affiliation(s)
| | - Rachel A Ross
- Albert Einstein College of Medicine, Bronx, NY, USA
- Beth Israel Deaconess Medical Center, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - David Q Johnson
- Indiana Biosciences Research Institute, Diabetes Research Center, Indianapolis, IN, USA
| | - Henning Fenselau
- Beth Israel Deaconess Medical Center, Boston, MA, USA
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Cologne, Germany
- Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - David L Haggerty
- Indiana University School of Medicine, Pharmacology and Toxicology, Indianapolis, IN, USA
| | - Brady Atwood
- Indiana University School of Medicine, Pharmacology and Toxicology, Indianapolis, IN, USA
| | - Bradford Lowell
- Beth Israel Deaconess Medical Center, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Jonathan N Flak
- Indiana Biosciences Research Institute, Diabetes Research Center, Indianapolis, IN, USA
- Indiana University School of Medicine, Pharmacology and Toxicology, Indianapolis, IN, USA
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI, USA
- Correspondence: Jonathan N. Flak, PhD, Indiana Biosciences Research Institute, 1345 W. 16th Street, Indianapolis, IN 46022, USA.
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20
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Rawlinson S, Andrews ZB. Hypothalamic insulin signalling as a nexus regulating mood and metabolism. J Neuroendocrinol 2021; 33:e12939. [PMID: 33634518 DOI: 10.1111/jne.12939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 01/23/2023]
Abstract
Insulin has long been known as a metabolic hormone critical in the treatment of diabetes for its peripheral effects on blood glucose. However, in the last 50 years, insulin has entered the realm of neuroendocrinology and many studies have described its function on insulin receptors in the brain in relation to both metabolic and mood disorders. Indeed, rodent models of impaired insulin signalling show signs of dysregulated energy and glucose homeostasis, as well as anxiety-like and depressive behaviours. Importantly, many metabolic diseases such as obesity and diabetes increase the risk of developing mood disorders; however, the brain mechanisms underlying the connection between metabolism and mood remain unresolved. We present the current literature on the importance of the insulin receptor with respect to regulating glucose and energy homeostasis and mood-related behaviours. Specifically, we hypothesise that the insulin receptor in the hypothalamus, classically known as the homeostatic centre of the brain, plays a causal role in linking metabolic and behavioural effects of insulin signalling. In this review, we discuss insulin signalling in the hypothalamus as a critical point of neural integration controlling metabolism and mood.
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Affiliation(s)
- Sasha Rawlinson
- Department of Physiology, Monash Biomedicine Discovery Institute Monash University, Clayton, VIC, Australia
| | - Zane B Andrews
- Department of Physiology, Monash Biomedicine Discovery Institute Monash University, Clayton, VIC, Australia
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21
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Alonge KM, D'Alessio DA, Schwartz MW. Brain control of blood glucose levels: implications for the pathogenesis of type 2 diabetes. Diabetologia 2021; 64:5-14. [PMID: 33043401 PMCID: PMC7718404 DOI: 10.1007/s00125-020-05293-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 08/10/2020] [Indexed: 12/22/2022]
Abstract
Despite a rapidly growing literature, the role played by the brain in both normal glucose homeostasis and in type 2 diabetes pathogenesis remains poorly understood. In this review, we introduce a framework for understanding the brain's essential role in these processes based on evidence that the brain, like the pancreas, is equipped to sense and respond to changes in the circulating glucose level. Further, we review evidence that glucose sensing by the brain plays a fundamental role in establishing the defended level of blood glucose, and that defects in this control system contribute to type 2 diabetes pathogenesis. We also consider the possibility that the close association between obesity and type 2 diabetes arises from a shared defect in the highly integrated neurocircuitry governing energy homeostasis and glucose homeostasis. Thus, whereas obesity is characterised by an increase in the defended level of the body's fuel stores (e.g. adipose mass), type 2 diabetes is characterised by an increase in the defended level of the body's available fuel (e.g. circulating glucose), with the underlying pathogenesis in each case involving impaired sensing of (or responsiveness to) relevant humoral negative feedback signals. This perspective is strengthened by growing preclinical evidence that in type 2 diabetes the defended level of blood glucose can be restored to normal by therapies that restore the brain's ability to properly sense the circulating glucose level. Graphical abstract.
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Affiliation(s)
- Kimberly M Alonge
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA, USA
| | - David A D'Alessio
- Duke Division of Endocrinology, Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Michael W Schwartz
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA, USA.
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22
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Pedroso JAB, Dos Santos LBP, Furigo IC, Spagnol AR, Wasinski F, List EO, Kopchick JJ, Donato J. Deletion of growth hormone receptor in hypothalamic neurons affects the adaptation capacity to aerobic exercise. Peptides 2021; 135:170426. [PMID: 33069692 PMCID: PMC7855886 DOI: 10.1016/j.peptides.2020.170426] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/08/2020] [Accepted: 10/10/2020] [Indexed: 12/12/2022]
Abstract
The hypothalamus mediates important exercise-induced metabolic adaptations, possibly via hormonal signals. Hypothalamic leptin receptor (LepR)- and steroidogenic factor 1 (SF1)-expressing neurons are directly responsive to growth hormone (GH) and deletion of GH receptor (GHR) in these cells impairs neuroendocrine responses during situations of metabolic stress. In the present study, we determined whether GHR ablation in LepR- or SF1-expressing cells modifies acute and chronic metabolic adaptations to exercise. Male mice carrying deletion of GHR in LepR- or SF1-expressing cells were submitted to 8 weeks of treadmill running training. Changes in aerobic performance and exercise-induced metabolic adaptations were determined. Mice carrying GHR deletion in LepR cells showed increased aerobic performance after 8 weeks of treadmill training, whereas GHR ablation in SF1 cells prevented improvement in running capacity. Trained mice carrying GHR ablation in SF1 cells exhibited increased fat mass and reduced cross-sectional area of the gastrocnemius muscle. In contrast, deletion of GHR in LepR cells reduced fat mass and increased gastrocnemius muscle hypertrophy, energy expenditure and voluntary locomotor activity in trained mice. Although glucose tolerance was not significantly affected by targeted deletions, glycemia before and immediately after maximum running tests was altered by GHR ablation. In conclusion, GHR signaling in hypothalamic neurons regulates the adaptation capacity to aerobic exercise in a cell-specific manner. These findings suggest that GH may represent a hormonal cue that informs specific hypothalamic neurons to produce exercise-induced acute and chronic metabolic adaptations.
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Affiliation(s)
- João A B Pedroso
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, 05508-000, Brazil
| | - Lucas B P Dos Santos
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, 05508-000, Brazil
| | - Isadora C Furigo
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, 05508-000, Brazil
| | - Alexandre R Spagnol
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Farmacologia, Sao Paulo, 05508-000, Brazil
| | - Frederick Wasinski
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, 05508-000, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, 45701, USA
| | - Jose Donato
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, 05508-000, Brazil.
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23
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Deem JD, Faber CL, Pedersen C, Phan BA, Larsen SA, Ogimoto K, Nelson JT, Damian V, Tran MA, Palmiter RD, Kaiyala KJ, Scarlett JM, Bruchas MR, Schwartz MW, Morton GJ. Cold-induced hyperphagia requires AgRP neuron activation in mice. eLife 2020; 9:58764. [PMID: 33320088 PMCID: PMC7837681 DOI: 10.7554/elife.58764] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 12/14/2020] [Indexed: 01/16/2023] Open
Abstract
To maintain energy homeostasis during cold exposure, the increased energy demands of thermogenesis must be counterbalanced by increased energy intake. To investigate the neurobiological mechanisms underlying this cold-induced hyperphagia, we asked whether agouti-related peptide (AgRP) neurons are activated when animals are placed in a cold environment and, if so, whether this response is required for the associated hyperphagia. We report that AgRP neuron activation occurs rapidly upon acute cold exposure, as do increases of both energy expenditure and energy intake, suggesting the mere perception of cold is sufficient to engage each of these responses. We further report that silencing of AgRP neurons selectively blocks the effect of cold exposure to increase food intake but has no effect on energy expenditure. Together, these findings establish a physiologically important role for AgRP neurons in the hyperphagic response to cold exposure.
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Affiliation(s)
- Jennifer D Deem
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Chelsea L Faber
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Christian Pedersen
- Department of Bioengineering, University of Washington, Seattle, United States
| | - Bao Anh Phan
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Sarah A Larsen
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Kayoko Ogimoto
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Jarrell T Nelson
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Vincent Damian
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Megan A Tran
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Richard D Palmiter
- Department of Biochemistry, Howard Hughes Medical Institute, University of Washington, Seattle, United States
| | - Karl J Kaiyala
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, United States
| | - Jarrad M Scarlett
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States.,Department of Pediatric Gastroenterology and Hepatology, Seattle Children's Hospital, Seattle, United States
| | - Michael R Bruchas
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, United States.,Department of Pharmacology, University of Washington, Seattle, United States.,Center for the Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, United States
| | - Michael W Schwartz
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
| | - Gregory J Morton
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, United States
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24
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Chachlaki K, Prevot V. Nitric oxide signalling in the brain and its control of bodily functions. Br J Pharmacol 2020; 177:5437-5458. [PMID: 31347144 PMCID: PMC7707094 DOI: 10.1111/bph.14800] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 07/10/2019] [Accepted: 07/19/2019] [Indexed: 02/06/2023] Open
Abstract
Nitric oxide (NO) is a versatile molecule that plays key roles in the development and survival of mammalian species by endowing brain neuronal networks with the ability to make continual adjustments to function in response to moment-to-moment changes in physiological input. Here, we summarize the progress in the field and argue that NO-synthetizing neurons and NO signalling in the brain provide a core hub for integrating sensory- and homeostatic-related cues, control key bodily functions, and provide a potential target for new therapeutic opportunities against several neuroendocrine and behavioural abnormalities.
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Affiliation(s)
- Konstantina Chachlaki
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine BrainJean‐Pierre Aubert Research Centre, UMR‐S 1172LilleFrance
- School of MedicineUniversity of LilleLilleFrance
- CHU LilleFHU 1,000 days for HealthLilleFrance
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine BrainJean‐Pierre Aubert Research Centre, UMR‐S 1172LilleFrance
- School of MedicineUniversity of LilleLilleFrance
- CHU LilleFHU 1,000 days for HealthLilleFrance
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25
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The Role of Ventromedial Hypothalamus Receptors in the Central Regulation of Food Intake. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-020-10120-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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26
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Faber CL, Deem JD, Campos CA, Taborsky GJ, Morton GJ. CNS control of the endocrine pancreas. Diabetologia 2020; 63:2086-2094. [PMID: 32894319 PMCID: PMC7983553 DOI: 10.1007/s00125-020-05204-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/07/2020] [Indexed: 12/30/2022]
Abstract
Increasing evidence suggests that, although pancreatic islets can function autonomously to detect and respond to changes in the circulating glucose level, the brain cooperates with the islet to maintain glycaemic control. Here, we review the role of the central and autonomic nervous systems in the control of the endocrine pancreas, including mechanisms whereby the brain senses circulating blood glucose levels. We also examine whether dysfunction in these systems might contribute to complications of type 1 diabetes and the pathogenesis of type 2 diabetes. Graphical abstract.
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Affiliation(s)
- Chelsea L Faber
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, 750 Republican St, Box 358062, Seattle, WA, 98109, USA
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Jennifer D Deem
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, 750 Republican St, Box 358062, Seattle, WA, 98109, USA
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Carlos A Campos
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, 750 Republican St, Box 358062, Seattle, WA, 98109, USA
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Gerald J Taborsky
- Department of Medicine, University of Washington, Seattle, WA, USA
- Veterans Affairs Puget Sound Health Care System, Department of Veterans Affairs Medical Center, Seattle, WA, USA
| | - Gregory J Morton
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, 750 Republican St, Box 358062, Seattle, WA, 98109, USA.
- Department of Medicine, University of Washington, Seattle, WA, USA.
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27
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Moiseev KY, Vishnyakova PA, Porseva VV, Masliukov AP, Spirichev AA, Emanuilov AI, Masliukov PM. Changes of nNOS expression in the tuberal hypothalamic nuclei during ageing. Nitric Oxide 2020; 100-101:1-6. [DOI: 10.1016/j.niox.2020.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/05/2020] [Accepted: 04/06/2020] [Indexed: 12/11/2022]
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28
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Interaction of glucose sensing and leptin action in the brain. Mol Metab 2020; 39:101011. [PMID: 32416314 PMCID: PMC7267726 DOI: 10.1016/j.molmet.2020.101011] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/27/2020] [Accepted: 05/05/2020] [Indexed: 01/10/2023] Open
Abstract
Background In response to energy abundant or deprived conditions, nutrients and hormones activate hypothalamic pathways to maintain energy and glucose homeostasis. The underlying CNS mechanisms, however, remain elusive in rodents and humans. Scope of review Here, we first discuss brain glucose sensing mechanisms in the presence of a rise or fall of plasma glucose levels, and highlight defects in hypothalamic glucose sensing disrupt in vivo glucose homeostasis in high-fat fed, obese, and/or diabetic conditions. Second, we discuss brain leptin signalling pathways that impact glucose homeostasis in glucose-deprived and excessed conditions, and propose that leptin enhances hypothalamic glucose sensing and restores glucose homeostasis in short-term high-fat fed and/or uncontrolled diabetic conditions. Major conclusions In conclusion, we believe basic studies that investigate the interaction of glucose sensing and leptin action in the brain will address the translational impact of hypothalamic glucose sensing in diabetes and obesity.
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29
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Faber CL, Matsen ME, Meek TH, Krull JE, Morton GJ. Adaptable Angled Stereotactic Approach for Versatile Neuroscience Techniques. J Vis Exp 2020. [PMID: 32449706 DOI: 10.3791/60965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Stereotactic surgery is an essential tool in the modern neuroscience lab. However, the ability to precisely and accurately target difficult-to-reach brain regions still presents a challenge, particularly when targeting brain structures along the midline. These challenges include avoiding of the superior sagittal sinus and third ventricle and the ability to consistently target selective and discrete brain nuclei. In addition, more advanced neuroscience techniques (e.g., optogenetics, fiber photometry, and two-photon imaging) rely on targeted implantation of significant hardware to the brain, and spatial limitations are a common hindrance. Presented here is a modifiable protocol for stereotactic targeting of rodent brain structures using an angled coronal approach. It can be adapted to 1) mouse or rat models, 2) various neuroscience techniques, and 3) multiple brain regions. As a representative example, it includes the calculation of stereotactic coordinates for targeting of the mouse hypothalamic ventromedial nucleus (VMN) for an optogenetic inhibition experiment. This procedure begins with the bilateral microinjection of an adeno-associated virus (AAV) encoding a light-sensitive chloride channel (SwiChR++) to a Cre-dependent mouse model, followed by the angled bilateral implantation of fiberoptic cannulae. Using this approach, findings show that activation of a subset of VMN neurons is required for intact glucose counterregulatory responses to insulin-induced hypoglycemia.
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30
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Raitiere MN. Does photoperiodism involve a seasonal and non-pathological Warburg effect? Med Hypotheses 2020; 135:109447. [DOI: 10.1016/j.mehy.2019.109447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 10/20/2019] [Indexed: 12/15/2022]
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31
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Hirschberg PR, Sarkar P, Teegala SB, Routh VH. Ventromedial hypothalamus glucose-inhibited neurones: A role in glucose and energy homeostasis? J Neuroendocrinol 2020; 32:e12773. [PMID: 31329314 PMCID: PMC7074896 DOI: 10.1111/jne.12773] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/18/2019] [Accepted: 07/14/2019] [Indexed: 12/20/2022]
Abstract
The ventromedial hypothalamus (VMH) plays a complex role in glucose and energy homeostasis. The VMH is necessary for the counter-regulatory response to hypoglycaemia (CRR) that increases hepatic gluconeogenesis to restore euglycaemia. On the other hand, the VMH also restrains hepatic glucose production during euglycaemia and stimulates peripheral glucose uptake. The VMH is also important for the ability of oestrogen to increase energy expenditure. This latter function is mediated by VMH modulation of the lateral/perifornical hypothalamic area (lateral/perifornical hypothalamus) orexin neurones. Activation of VMH AMP-activated protein kinase (AMPK) is necessary for the CRR. By contrast, VMH AMPK inhibition favours decreased basal glucose levels and is required for oestrogen to increase energy expenditure. Specialised VMH glucose-sensing neurones confer the ability to sense and respond to changes in blood glucose levels. Glucose-excited (GE) neurones increase and glucose-inhibited (GI) neurones decrease their activity as glucose levels rise. VMH GI neurones, in particular, appear to be important in the CRR, although a role for GE neurones cannot be discounted. AMPK mediates glucose sensing in VMH GI neurones suggesting that, although activation of these neurones is important for the CRR, it is necessary to silence them to lower basal glucose levels and enable oestrogen to increase energy expenditure. In support of this, we found that oestrogen reduces activation of VMH GI neurones in low glucose by inhibiting AMPK. In this review, we present the evidence underlying the role of the VMH in glucose and energy homeostasis. We then discuss the role of VMH glucose-sensing neurones in mediating these effects, with a strong emphasis on oestrogenic regulation of glucose sensing and how this may affect glucose and energy homeostasis.
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Affiliation(s)
- Pamela R Hirschberg
- Department of Pharmacology, Physiology and Neurosciences, Rutgers New Jersey Medical School, The State University of New Jersey, Newark, NJ, USA
| | - Pallabi Sarkar
- Department of Pharmacology, Physiology and Neurosciences, Rutgers New Jersey Medical School, The State University of New Jersey, Newark, NJ, USA
| | - Suraj B Teegala
- Department of Pharmacology, Physiology and Neurosciences, Rutgers New Jersey Medical School, The State University of New Jersey, Newark, NJ, USA
| | - Vanessa H Routh
- Department of Pharmacology, Physiology and Neurosciences, Rutgers New Jersey Medical School, The State University of New Jersey, Newark, NJ, USA
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32
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Furigo IC, de Souza GO, Teixeira PDS, Guadagnini D, Frazão R, List EO, Kopchick JJ, Prada PO, Donato J. Growth hormone enhances the recovery of hypoglycemia via ventromedial hypothalamic neurons. FASEB J 2019; 33:11909-11924. [PMID: 31366244 DOI: 10.1096/fj.201901315r] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Growth hormone (GH) is secreted during hypoglycemia, and GH-responsive neurons are found in brain areas containing glucose-sensing neurons that regulate the counter-regulatory response (CRR). However, whether GH modulates the CRR to hypoglycemia via specific neuronal populations is currently unknown. Mice carrying ablation of GH receptor (GHR) either in leptin receptor (LepR)- or steroidogenic factor-1 (SF1)-expressing cells were studied. We also investigated the importance of signal transducer and activator of transcription 5 (STAT5) signaling in SF1 cells for the CRR. GHR ablation in LepR cells led to impaired capacity to recover from insulin-induced hypoglycemia and to a blunted CRR caused by 2-deoxy-d-glucose (2DG) administration. GHR inactivation in SF1 cells, which include ventromedial hypothalamic neurons, also attenuated the CRR. The reduced CRR was prevented by parasympathetic blockers. Additionally, infusion of 2DG produced an abnormal hyperactivity of parasympathetic preganglionic neurons, whereas the 2DG-induced activation of anterior bed nucleus of the stria terminalis neurons was reduced in mice without GHR in SF1 cells. Mice carrying ablation of Stat5a/b genes in SF1 cells showed no defects in the CRR. In summary, GHR expression in SF1 cells is required for a normal CRR, and these effects are largely independent of STAT5 pathway.-Furigo, I. C., de Souza, G. O., Teixeira, P. D. S., Guadagnini, D., Frazão, R., List, E. O., Kopchick, J. J., Prada, P. O., Donato, J., Jr. Growth hormone enhances the recovery of hypoglycemia via ventromedial hypothalamic neurons.
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Affiliation(s)
- Isadora C Furigo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gabriel O de Souza
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Pryscila D S Teixeira
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Dioze Guadagnini
- School of Applied Sciences, State University of Campinas, Limeira, Brazil
| | - Renata Frazão
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Edward O List
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, USA
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, USA
| | - Patricia O Prada
- School of Applied Sciences, State University of Campinas, Limeira, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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33
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Brown JM, Scarlett JM, Schwartz MW. Rethinking the role of the brain in glucose homeostasis and diabetes pathogenesis. J Clin Invest 2019; 129:3035-3037. [PMID: 31329157 PMCID: PMC6668663 DOI: 10.1172/jci130904] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Jenny M. Brown
- University of Washington Medicine Diabetes Institute, Department of Medicine, and
| | - Jarrad M. Scarlett
- University of Washington Medicine Diabetes Institute, Department of Medicine, and
- Department of Pediatric Gastroenterology and Hepatology, University of Washington, Seattle, Washington, USA
| | - Michael W. Schwartz
- University of Washington Medicine Diabetes Institute, Department of Medicine, and
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34
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Abstract
Glucose-sensitive neurons have long been implicated in glucose homeostasis, but how glucose-sensing information is used by the brain in this process remains uncertain. Here, we propose a model in which (1) information relevant to the circulating glucose level is essential to the proper function of this regulatory system, (2) this input is provided by neurons located outside the blood-brain barrier (BBB) (since neurons situated behind the BBB are exposed to glucose in brain interstitial fluid, rather than that in the circulation), and (3) while the efferent limb of this system is comprised of neurons situated behind the BBB, many of these neurons are also glucose sensitive. Precedent for such an organizational scheme is found in the thermoregulatory system, which we draw upon in this framework for understanding the role played by brain glucose sensing in glucose homeostasis.
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Affiliation(s)
- Marie Aare Bentsen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Science, University of Copenhagen, Blegdamsvej 3B, Building 7 (Maersk Tower), Copenhagen N 2200, Denmark; University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington at South Lake Union, 750 Republican St, F704, Box 358062, Seattle, WA 98109, USA
| | - Zaman Mirzadeh
- Department of Neurological Surgery, Barrow Neurological Institute, 350 West Thomas Road, Phoenix, AZ 85013, USA
| | - Michael W Schwartz
- University of Washington Medicine Diabetes Institute, Department of Medicine, University of Washington at South Lake Union, 750 Republican St, F704, Box 358062, Seattle, WA 98109, USA.
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