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Sapkota S, Briski KP. Sex-Dimorphic Effects of Hypoglycemia on Metabolic Sensor mRNA Expression in Ventromedial Hypothalamic Nucleus-Dorsomedial Division (VMNdm) Growth Hormone-Releasing Hormone Neurons. ACS Chem Neurosci 2024. [PMID: 38757688 DOI: 10.1021/acschemneuro.4c00206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024] Open
Abstract
Growth hormone-releasing hormone (Ghrh) neurons in the dorsomedial ventromedial hypothalamic nucleus (VMNdm) express the metabolic transcription factor steroidogenic factor-1 and hypoglycemia-sensitive neurochemicals of diverse chemical structures, transmission modes, and temporal signaling profiles. Ghrh imposes neuromodulatory control of coexpressed transmitters. Multiple metabolic sensory mechanisms are employed in the brain, including screening of the critical nutrient glucose or the energy currency ATP. Here, combinatory laser-catapult-microdissection/single-cell multiplex qPCR tools were used to investigate whether these neurons possess molecular machinery for monitoring cellular metabolic status and if these biomarkers exhibit sex-specific sensitivity to insulin-induced hypoglycemia. Data show that hypoglycemia up- (male) or downregulated (female) Ghrh neuron glucokinase (Gck) mRNA; Ghrh gene silencing decreased baseline and hypoglycemic patterns of Gck gene expression in each sex. Ghrh neuron glucokinase regulatory protein (Gckr) transcript levels were respectively diminished or augmented in hypoglycemic male vs female rats; this mRNA profile was decreased by Ghrh siRNA in both sexes. Gene transcripts encoding catalytic alpha subunits of the energy monitor 5-AMP-activated protein kinase (AMPK), i.e., Prkaa1 and 2, were increased by hypoglycemia in males, yet only the former mRNA was hypoglycemia-sensitive in females. Ghrh siRNA downregulated baseline and hypoglycemia-associated Prkaa subunit mRNAs in males but elicited divergent changes in Prkaa2 transcripts in eu- vs hypoglycemic females. Results provide unique evidence that VMNdm Ghrh neurons express the characterized metabolic sensor biomarkers glucokinase and AMPK and that the corresponding gene profiles exhibit distinctive sex-dimorphic transcriptional responses to hypoglycemia. Data further document Ghrh neuromodulation of baseline and hypoglycemic transcription patterns of these metabolic gene profiles.
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Affiliation(s)
- Subash Sapkota
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, Louisiana 71201, United States
| | - Karen P Briski
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, Louisiana 71201, United States
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2
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Sung Y, Yu YC, Han JM. Nutrient sensors and their crosstalk. Exp Mol Med 2023; 55:1076-1089. [PMID: 37258576 PMCID: PMC10318010 DOI: 10.1038/s12276-023-01006-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/22/2023] [Accepted: 03/13/2023] [Indexed: 06/02/2023] Open
Abstract
The macronutrients glucose, lipids, and amino acids are the major components that maintain life. The ability of cells to sense and respond to fluctuations in these nutrients is a crucial feature for survival. Nutrient-sensing pathways are thus developed to govern cellular energy and metabolic homeostasis and regulate diverse biological processes. Accordingly, perturbations in these sensing pathways are associated with a wide variety of pathologies, especially metabolic diseases. Molecular sensors are the core within these sensing pathways and have a certain degree of specificity and affinity to sense the intracellular fluctuation of each nutrient either by directly binding to that nutrient or indirectly binding to its surrogate molecules. Once the changes in nutrient levels are detected, sensors trigger signaling cascades to fine-tune cellular processes for energy and metabolic homeostasis, for example, by controlling uptake, de novo synthesis or catabolism of that nutrient. In this review, we summarize the major discoveries on nutrient-sensing pathways and explain how those sensors associated with each pathway respond to intracellular nutrient availability and how these mechanisms control metabolic processes. Later, we further discuss the crosstalk between these sensing pathways for each nutrient, which are intertwined to regulate overall intracellular nutrient/metabolic homeostasis.
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Affiliation(s)
- Yulseung Sung
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon, 21983, South Korea
| | - Ya Chun Yu
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon, 21983, South Korea
| | - Jung Min Han
- Yonsei Institute of Pharmaceutical Sciences, College of Pharmacy, Yonsei University, Incheon, 21983, South Korea.
- Department of Integrated OMICS for Biomedical Science, Yonsei University, Seoul, 03722, South Korea.
- POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, 37673, South Korea.
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3
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Luo W, Li L, Zhang Y, Xu Z, Xiong Y, Guo Z, Zhang N, Zhang Y, Chen P, Wang Y, Du Z. Study on the Hyperglycemic Effect of GLP-1 in Spinibarbus denticulatus by Oral Administration and Intraperitoneal Injection Methods. AQUACULTURE NUTRITION 2023; 2023:9969406. [PMID: 37051050 PMCID: PMC10085660 DOI: 10.1155/2023/9969406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 03/14/2023] [Accepted: 03/21/2023] [Indexed: 06/19/2023]
Abstract
Glucagon-like peptide-1 (GLP-1), one of the expression products of the proglucagon (pg) gene, is an incretin mainly secreted by the gastrointestinal system. In mammals, GLP-1 has hypoglycemic and food-inhibiting effects; while in some fish species, it has been confirmed to increase blood glucose by promoting gluconeogenesis and stimulating glycogenolysis. In order to more deeply understand the role of GLP-1 in the process of glycometabolism in herbivorous fish, the pg gene was cloned from Spinibarbus denticulatus to obtain its sequence characteristics, and the changes in blood glucose level and pg gene expression in S. denticulatus were further explored by feeding with three kinds of carbohydrates and intraperitoneal injection of GLP-1. Basal and temporal blood glucose levels and pg gene expression of S. denticulatus (91.68 ± 10.79 g) were measured at 0, 1, 3, 5, 7, and 12 h after oral administration (n = 4). Then, the changes of blood glucose levels and pg and glucokinase (gk) gene expressions of S. denticulatus (94.29 ± 10.82 g) were determined at 0, 30, 60, and 120 min after intraperitoneal injection (n = 4). It was shown that polysaccharides could induce the upregulation of pg gene expression faster than monosaccharides and stimulate the secretion of GLP-1 in the intestine. Intraperitoneal injection of GLP-1 peptide rapidly raised blood glucose levels, and pg gene expression in the anterior intestine, whole brain, and hepatopancreas decreased continuously after 30 minutes. These results showed that S. denticulatus might inhibit the excessive accumulation of blood glucose by reducing the expression of the pg gene and increasing the expression of gk gene in a short time. It was speculated that GLP-1 of S. denticulatus might have a "gut-brain-liver" pathway similar to mammals in glycemia regulation. Therefore, this study provided a novel perspective for explaining the functional differences of GLP-1 in herbivorous fish and mammals.
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Affiliation(s)
- Wei Luo
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Luojia Li
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Yue Zhang
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Zhou Xu
- Mianyang Academy of Agricultural Sciences, Mianyang, Sichuan, China
| | - Yinlin Xiong
- The Original Stock Farm of Leiocassis longirostris of Sichuan Province, Chongzhou, Sichuan, China
| | - Zhonggang Guo
- Agricultural and Rural Bureau of Chongzhou, Chongzhou, Sichuan, China
| | - Ning Zhang
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Yibo Zhang
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Pengyu Chen
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Yan Wang
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
| | - Zongjun Du
- College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan, China
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4
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Mei Y, Li Y, Cheng Y, Gao L. The effect of gastric bypass surgery on cognitive function of Alzheimer's disease and the role of GLP1-SGLT1 pathway. Exp Neurol 2023; 363:114377. [PMID: 36893833 DOI: 10.1016/j.expneurol.2023.114377] [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: 12/13/2022] [Revised: 02/20/2023] [Accepted: 03/04/2023] [Indexed: 03/09/2023]
Abstract
OBJECTIVE Gastric bypass surgery has been shown to improve metabolic profiles via GLP1, which may also have cognitive benefits for Alzheimer's disease (AD) patients. However, the exact mechanism requires further investigation. METHODS Roux-en-Y gastric bypass or sham surgery was performed on APP/PS1/Tau triple transgenic mice (an AD mice model) or wild type C57BL/6 mice. Morris Water Maze (MWM) test was used to evaluate the cognitive function of mice and animal tissue samples were obtained for measurements two months after the surgery. Additionally, STC-1 intestine cells were treated with siTAS1R2 and siSGLT1, and HT22 nerve cells were treated with Aβ, siGLP1R, GLP1 and siSGLT1 in vitro to explore the role of GLP1-SGLT1 related signaling pathway in cognitive function. RESULTS The MWM test showed that bypass surgery significantly improved cognitive function in AD mice as measured by navigation and spatial probe tests. Moreover, bypass surgery reversed neurodegeneration, down-regulated hyperphosphorylation of Tau protein and Aβ deposition, improved glucose metabolism, and up-regulated the expression of GLP1, SGLT1, and TAS1R2/3 in the hippocampus. Furthermore, GLP1R silencing down-regulated SGLT1 expression, whereas SGLT1 silencing increased Tau protein deposition and exacerbated dysregulated of glucose metabolism in HT22 cells. However, RYGB did not alter the level of GLP1 secretion in the brainstem (where central GLP1 is mainly produced). Additionally, GLP1 expression was upregulated by RYGB via TAS1R2/3-SGLT1 activation sequentially in the small intestine. CONCLUSION RYGB surgery could improve cognition function in AD mice through facilitating glucose metabolism and reducing Tau phosphorylation and Aβ deposition in the hippocampus, mediated by peripheral serum GLP1 activation of SGLT1 in the brain. Furthermore, RYGB increased GLP1 expression through sequential activation of TAS1R2/TAS1R3 and SGLT1 in the small intestine.
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Affiliation(s)
- Yingna Mei
- Department of Endocrinology & Metabolism, Renmin Hospital of Wuhan University, China
| | - Yubing Li
- Department of Endocrinology & Metabolism, Renmin Hospital of Wuhan University, China
| | - Yanxiang Cheng
- Department of Obstetrics & Gynecology, Renmin Hospital of Wuhan University, China.
| | - Ling Gao
- Department of Endocrinology & Metabolism, Renmin Hospital of Wuhan University, China.
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Ye D, Huang J, Wu J, Xie K, Gao X, Yan K, Zhang P, Tao Y, Li Y, Zang S, Rong X, Li J, Guo J. Integrative metagenomic and metabolomic analyses reveal gut microbiota-derived multiple hits connected to development of gestational diabetes mellitus in humans. Gut Microbes 2023; 15:2154552. [PMID: 36550785 PMCID: PMC9794004 DOI: 10.1080/19490976.2022.2154552] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Gestational diabetes mellitus (GDM) is characterized by the development of hyperglycemia and insulin resistance during the second or third trimester of pregnancy, associated with considerable risks to both the mother and developing fetus. Although emerging evidence suggests an association between the altered gut microbiota and GDM, remarkably little is known about the microbial and metabolic mechanisms that link the dysbiosis of the gut microbiota to the development of GDM. In this study, a metagenome-wide association study and serum metabolomics profiling were performed in a cohort of pregnant women with GDM and pregnant women with normal glucose tolerance (NGT). We identified gut microbial alterations associated with GDM and linked to the changes in circulating metabolites. Blood metabolite profiles revealed that GDM patients exhibited a marked increase in 2-hydroxybutyric acid and L-alpha-aminobutyric acid, but a decrease in methionine sulfoxide, allantoin, and dopamine and dopaminergic synapse, when compared with those in NGT controls. Short-chain fatty acid-producing genera, including Faecalibacterium, Prevotella, and Streptococcus, and species Bacteroides coprophilus, Eubacterium siraeum, Faecalibacterium prausnitzii, Prevotella copri, and Prevotella stercorea, were significantly reduced in GDM patients relative to those in NGT controls. Bacterial co-occurrence network analysis revealed that pro-inflammatory bacteria were over-represented as the core species in GDM patients. These microbial and metabolic signatures are closely associated with clinical parameters of glucose metabolism in GDM patients and NGT controls. In conclusion, we identified circulating dopamine insufficiency, imbalanced production of SCFAs, and excessive metabolic inflammation as gut microbiota-driven multiple parallel hits linked to GDM development. This work might explain in part the mechanistic link between altered gut microbiota and GDM pathogenesis, and suggest that gut microbiota may serve as a promising target to intervene in GDM.
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Affiliation(s)
- Dewei Ye
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China,Key Laboratory of Metabolic Phenotyping in Model Animals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jiating Huang
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China,Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
| | - Jiaming Wu
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China,Key Laboratory of Metabolic Phenotyping in Model Animals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Kang Xie
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Xiang Gao
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Kaixuan Yan
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China,Key Laboratory of Metabolic Phenotyping in Model Animals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Pengfei Zhang
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China,Key Laboratory of Metabolic Phenotyping in Model Animals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Ying Tao
- The First Affiliated Hospital/School of Clinical Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Yun Li
- The First Affiliated Hospital/School of Clinical Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shufei Zang
- Department of Endocrinology, Shanghai Fifth People’s Hospital, Fudan University, Shanghai, China
| | - Xianglu Rong
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jun Li
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China,Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong, China,School of Data Science, City University of Hong Kong, Hong Kong, China
| | - Jiao Guo
- Key Laboratory of Glucolipid Metabolic Diseases of the Ministry of Education, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou, China,Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, China,CONTACT Jiao Guo Science and Technology Building, Guangdong Pharmaceutical University, Guangzhou Higher Education Mega, 280 Waihuan East Road, Room 403, 4th Floor, Guangzhou, China
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6
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Herring RA, Shojaee-Moradie F, Stevenage M, Parsons I, Jackson N, Mendis J, Middleton B, Umpleby AM, Fielding BA, Davies M, Russell-Jones DL. The SGLT2 Inhibitor Dapagliflozin Increases the Oxidation of Ingested Fatty Acids to Ketones in Type 2 Diabetes. Diabetes Care 2022; 45:1408-1415. [PMID: 35312749 DOI: 10.2337/dc21-2043] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/22/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To investigate the mechanism for increased ketogenesis following treatment with the SGLT2 inhibitor dapagliflozin in people with type 2 diabetes. RESEARCH DESIGN AND METHODS The design was a double-blind, placebo-controlled, crossover study with a 4-week washout period. Participants received dapagliflozin or placebo in random order for 4 weeks. After each treatment, they ingested 30 mL of olive oil containing [U-13C]palmitate to measure ketogenesis, with blood sampling for 480 min. Stable isotopes of glucose and glycerol were infused to measure glucose flux and lipolysis, respectively, at 450-480 min. RESULTS Glucose excretion rate was higher and peripheral glucose uptake lower with dapagliflozin than placebo. Plasma β-hydroxybutyrate (BOHB) concentrations and [13C2]BOHB concentrations were higher and glucose concentrations lower with dapagliflozin than placebo. Nonesterified fatty acids (NEFAs) were higher with dapagliflozin at 300 and 420 min, but lipolysis at 450-480 min was not different. Triacylglycerol at all time points and endogenous glucose production rate at 450-480 min were not different between treatments. CONCLUSIONS The increase in ketone enrichment from the ingested palmitic acid tracer suggests that meal-derived fatty acids contribute to the increase in ketones during treatment with dapagliflozin. The increase in BOHB concentration with dapagliflozin occurred with only minimal changes in plasma NEFA concentration and no change in lipolysis. This finding suggests a metabolic switch to increase ketogenesis within the liver.
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Affiliation(s)
- Roselle A Herring
- Centre for Endocrinology, Diabetes and Research, Royal Surrey NHS Foundation Trust, Guildford, U.K.,Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Fariba Shojaee-Moradie
- Centre for Endocrinology, Diabetes and Research, Royal Surrey NHS Foundation Trust, Guildford, U.K
| | - Mary Stevenage
- Centre for Endocrinology, Diabetes and Research, Royal Surrey NHS Foundation Trust, Guildford, U.K
| | - Iain Parsons
- Centre for Endocrinology, Diabetes and Research, Royal Surrey NHS Foundation Trust, Guildford, U.K
| | - Nicola Jackson
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Jeewaka Mendis
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Benita Middleton
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - A Margot Umpleby
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Barbara A Fielding
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Melanie Davies
- Diabetes Research Centre, University of Leicester, Leicester, U.K.,National Institute for Health Research Leicester Biomedical Research Centre, Leicester, U.K
| | - David L Russell-Jones
- Centre for Endocrinology, Diabetes and Research, Royal Surrey NHS Foundation Trust, Guildford, U.K.,Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
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7
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Tripathi R, Banerjee SK, Nirala JP, Mathur R. Simultaneous exposure to electromagnetic field from mobile phone and unimpeded fructose drinking during pre-, peri-, and post-pubertal stages perturbs the hypothalamic and hepatic regulation of energy homeostasis by early adulthood: experimental evidence. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:7438-7451. [PMID: 34476698 DOI: 10.1007/s11356-021-15841-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
The present-day children-adolescents ubiquitously use the mobile phones and unrestrictedly consume fructose-laden diet. Unfortunately, a rise in the incidence of insulin resistance and fatty liver syndrome in young adults has also been recorded. To delineate a possible correlate, the effect of exposure to electromagnetic field (EMF) from the mobile phone and unrestricted fructose intake during pre-, peri-, and post-pubertal stages of development on orexigenic and anorexigenic signals arising from the hypothalamus and liver of rats is investigated here. The study design included four arms, i.e., "Normal", "Exposure Only (ExpO)", "Fructose Only (FruO)", and "Exposure with Fructose (EF)", wherein weaned rats received either "normal chow and drinking water" or "normal chow and fructose (15%) drinking solution" in presence and absence of EMF exposure (2 h/day) for 8 weeks. The results indicate that the total calories consumed by the EF were higher by early adulthood than normal, possibly under the influence of the raised levels of the orexigenic hormone, i.e., ghrelin, and it reflected as raised rate of weight gain. At early adulthood, the EF recorded mitigated response and sensitivity of insulin. Despite EF being a "fed-state", both centrally and peripherally, the glycolysis was restrained, but the gluconeogenesis was raised. Additionally, the altered lipid profile and the glycogen levels indicate that the EF developed fatty liver. The energy homeostasis of the EF was compromised as evidenced by (a) reduced expression of the glucosensors-GLUT2 and glucokinase in the hypothalamus and liver and (b) reduced expression of the cellular energy regulator-AMPK, orexigenic peptide-NPY, and anorexigenic peptide-POMC in the hypothalamus. Taken together, the present study evidences that the exposure to EMFfrom the mobile phone and unrestricted fructose intake during childhood-adolescence impairs the central and peripheral pathways that mediate the glucosensing, glucoregulation, feeding, and satiety behavior by early adulthood.
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Affiliation(s)
- Ruchi Tripathi
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences & Research, New Delhi, India
| | - Sanjay Kumar Banerjee
- Drug Discovery Research Centre, Translational Health Science and Technology Institute, Faridabad, India
- Current Address: Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Guwahati, India
| | - Jay Prakash Nirala
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Rajani Mathur
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences & Research, New Delhi, India.
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Li B, Zhang B, Liu X, Zheng Y, Han K, Liu H, Wu C, Li J, Fan S, Peng W, Zhang F, Liu X. The effect of lactoferrin in aging: role and potential. Food Funct 2021; 13:501-513. [PMID: 34928288 DOI: 10.1039/d1fo02750f] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Aging is frequently accompanied by various types of physiological deterioration, which increases the risk of human pathologies. Global public health efforts to increase human lifespan have increasingly focused on lowering the risk of aging-related diseases, such as diabetes, neurodegenerative diseases, cardiovascular disease, and cancers. Dietary intervention is a promising approach to maintaining human health during aging. Lactoferrin (LF) is known for its physiologically pleiotropic properties. Anti-aging interventions of LF have proven to be safe and effective for various pharmacological activities, such as anti-oxidation, anti-cellular senescence, anti-inflammation, and anti-carcinogenic. Moreover, LF has a pivotal role in modulating the major signaling pathways that influence the longevity of organisms. Thus, LF is expected to be able to attenuate the process of aging and greatly ameliorate its effects.
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Affiliation(s)
- Bing Li
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Bo Zhang
- Henan Key Laboratory of Rare Earth Functional Materials, The Key Laboratory of Rare Earth Functional Materials and Applications, Zhoukou Normal University, Zhoukou 466001, Henan, PR China
| | - Xudong Liu
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Yidan Zheng
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Kuntong Han
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Henan Liu
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Changjing Wu
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Jin Li
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Shuhua Fan
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Weifeng Peng
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Fuli Zhang
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
| | - Xiaomeng Liu
- Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou 466001, Henan, PR China.
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9
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Interplay between bioenergetics and oxidative stress at normal brain aging. Aging as a result of increasing disbalance in the system oxidative stress-energy provision. Pflugers Arch 2021; 473:713-722. [PMID: 33599804 DOI: 10.1007/s00424-021-02531-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 01/18/2021] [Accepted: 02/01/2021] [Indexed: 12/13/2022]
Abstract
At normal aging, the brain exhibits signs of compromised bioenergetic and increased levels of products of interaction between reactive oxygen/nitrogen species (ROS/RNS) and brain constituents. Under normal conditions, steady-state levels of ATP and ROS/RNS fluctuate in certain ranges providing basis for stable homeostasis. However, from time to time these parameters leave a "comfort zone," and at adulthood, organisms are able to cope with these challenges efficiently, whereas at aging, efficiency of the systems maintaining homeostasis declines. That is very true for the brain due to high ATP demands which are mainly covered by mitochondrial oxidative phosphorylation. Such active oxidative metabolism gives rise to intensive ROS generation as side products. The situation is worsened by high brain level of polyunsaturated fatty acids which are substrates for ROS/RNS attack and production of lipid peroxides. In this review, organization of energetic metabolism in the brain with a focus on its interplay with ROS at aging is discussed. The working hypothesis on aging as a disbalance between oxidative stress and energy provision as a reason for brain aging is proposed. From this point of view, normal age-related physiological decline in the brain functions results from increased disbalance between decrease in capability of the brain to control constantly increased incapability to maintain ROS levels and produce ATP due to amplification of vicious cycles intensification of oxidative stress <----> impairment of energy provision.
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10
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Canosa LF, Bertucci JI. Nutrient regulation of somatic growth in teleost fish. The interaction between somatic growth, feeding and metabolism. Mol Cell Endocrinol 2020; 518:111029. [PMID: 32941926 DOI: 10.1016/j.mce.2020.111029] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 07/03/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022]
Abstract
This review covers the current knowledge on the regulation of the somatic growth axis and its interaction with metabolism and feeding regulation. The main endocrine and neuroendocrine factors regulating both the growth axis and feeding behavior will be briefly summarized. Recently discovered neuropeptides and peptide hormones will be mentioned in relation to feeding control as well as growth hormone regulation. In addition, the influence of nutrient and nutrient sensing mechanisms on growth axis will be highlighted. We expect that in this process gaps of knowledge will be exposed, stimulating future research in those areas.
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Affiliation(s)
- Luis Fabián Canosa
- Instituto Tecnológico de Chascomús (INTECH), CONICET-UNSAM, Chascomús, Buenos Aires, Argentina.
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11
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Xu X, Liu B, Yang J, Zou Y, Sun M, Li Z, Li L, Yang R, Zou L, Li G, Liu S, Li G, Liang S. Glucokinase in stellate ganglia cooperates with P2X3 receptor to develop cardiac sympathetic neuropathy in type 2 diabetes rats. Brain Res Bull 2020; 165:290-297. [PMID: 33091480 DOI: 10.1016/j.brainresbull.2020.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 09/19/2020] [Accepted: 10/05/2020] [Indexed: 12/23/2022]
Abstract
Glucokinase (GCK) may be involved in inflammatory pathological changes, while the P2X3 receptor in the stellate ganglia (SG) is related to diabetic cardiac autonomic neuropathy. In this study, we explored the relationship between the upregulated GCK in SG and diabetic cardiac sympathy. The expression and location of GCK and P2X3 in SG of type 2 diabetes mellitus (T2DM) rats were assessed. Changes in cardiac function were determined by measuring blood pressure, sympathetic nerve activity, heart rate, and heart rate variability. P2X3 agonist-activated currents in isolated stellate ganglion neurons and cultured human embryonic kidney 293 (HEK293) cells were recorded using whole-cell patch clamp techniques. The upregulated expression of GCK in SG of T2DM rats was decreased after treatment with GCK short hairpin RNA (shRNA). GCK shRNA treatment also improved the blood pressure, sympathetic nerve activity, heart rate, and heart rate variability in T2DM rats. By contrast, the expression of P2X3 and tumor necrosis factor α (TNF-α) was lessened by GCK shRNA treatment. In addition, adenosine triphosphate (ATP)-activated currents in stellate ganglion neurons and HEK293 cells co-transfected with GCK and P2X3 receptor plasmids were reduced after GCK shRNA treatment. In T2DM rats, knockdown of GCK relieved the diabetic cardiac sympathy mediated by P2X3 receptor-involved upregulation of GCK in SG.
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Affiliation(s)
- Xiumei Xu
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Baoe Liu
- Undergraduate Student of Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Jingjian Yang
- Undergraduate Student of Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Yuting Zou
- Undergraduate Student of Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Minghao Sun
- Undergraduate Student of Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Zijing Li
- Undergraduate Student of Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Lin Li
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Runan Yang
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Lifang Zou
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Guilin Li
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Shuangmei Liu
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Guodong Li
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Shangdong Liang
- Neuropharmacology Laboratory of Physiology Department, Basic Medical College of Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China; Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, Jiangxi, 330006, People's Republic of China.
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12
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Kim YR, Hildebrandt T, Mayer LES. Differential glucose metabolism in weight restored women with anorexia nervosa. Psychoneuroendocrinology 2019; 110:104404. [PMID: 31541915 PMCID: PMC8666139 DOI: 10.1016/j.psyneuen.2019.104404] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 07/21/2019] [Accepted: 08/06/2019] [Indexed: 01/07/2023]
Abstract
Women with anorexia nervosa (AN) develop visceral adiposity associated with insulin resistance after partial weight restoration, but little is known about the glucose homeostasis after full weight restoration. In this investigation, we studied glucose homeostasis in twenty-four women with AN before (AN) and after weight restoration (WR) at a single institution, with both restricting and binge-purge subtypes (>70% binge-purge), compared to gender-, age- and BMI-matched healthy controls (HC). Participants underwent fasting plasma hormone analysis, oral glucose tolerance test (OGTT), and body composition analysis. Glucose homeostasis was assessed by the homeostasis model assessment (HOMA) and OGTT, and parameters were analyzed for association with body composition. We observed that a subset of the WR patients (21%) had metabolically unhealthy HOMA insulin resistance estimates (HOMA-IR), while this was not seen in the control group. Overall mean HOMA-IR between groups were not significantly different. Mean glucose reactivity was higher in the WR group than HC women (p = 0.008, Hedges' g = 0.811), and time-adjusted glucose reactivity in the WR group was inversely associated with visceral adiposity (r = -0.559, p = 0.006), but not with fat mass (r = -273, p = 0.208) or lean mass (r = -0.002, p = 0.994). Our findings suggest that glucose response during the OGTT in women with AN is altered in association with visceral adiposity acutely after full weight restoration, but that they do not develop overt insulin resistance. Glucometabolic profiling could offer novel insights to energy homeostasis acutely after weight restoration.
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Affiliation(s)
- Youngjung R. Kim
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai Hospital, New York, NY 10029 USA
| | - Thomas Hildebrandt
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai Hospital, New York, NY 10029, USA.
| | - Laurel E. S. Mayer
- Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University and New York State Psychiatric Institute, New York, NY 10032 USA
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13
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Abstract
The hypothalamus is the brain region responsible for the maintenance of energetic homeostasis. The regulation of this process arises from the ability of the hypothalamus to orchestrate complex physiological responses such as food intake and energy expenditure, circadian rhythm, stress response, and fertility. Metabolic alterations such as obesity can compromise these hypothalamic regulatory functions. Alterations in circadian rhythm, stress response, and fertility further contribute to aggravate the metabolic dysfunction of obesity and contribute to the development of chronic disorders such as depression and infertility.At cellular level, obesity caused by overnutrition can damage the hypothalamus promoting inflammation and impairing hypothalamic neurogenesis. Furthermore, hypothalamic neurons suffer apoptosis and impairment in synaptic plasticity that can compromise the proper functioning of the hypothalamus. Several factors contribute to these phenomena such as ER stress, oxidative stress, and impairments in autophagy. All these observations occur at the same time and it is still difficult to discern whether inflammatory processes are the main drivers of these cellular dysfunctions or if the hypothalamic hormone resistance (insulin, leptin, and ghrelin) can be pinpointed as the source of several of these events.Understanding the mechanisms that underlie the pathophysiology of obesity in the hypothalamus is crucial for the development of strategies that can prevent or attenuate the deleterious effects of obesity.
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14
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Ding N, Peng P, Chu YJ, Wang JJ, Chen SY, Arulthas R, Deng YQ. The effects of O-GlcNAc alteration on Alzheimer-like neurodegeneration in SK-N-SH cells. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2018; 162:243-248. [DOI: 10.5507/bp.2018.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 07/17/2018] [Indexed: 11/23/2022] Open
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15
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López-Gambero AJ, Martínez F, Salazar K, Cifuentes M, Nualart F. Brain Glucose-Sensing Mechanism and Energy Homeostasis. Mol Neurobiol 2018; 56:769-796. [PMID: 29796992 DOI: 10.1007/s12035-018-1099-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/25/2018] [Indexed: 01/02/2023]
Abstract
The metabolic and energy state of the organism depends largely on the availability of substrates, such as glucose for ATP production, necessary for maintaining physiological functions. Deregulation in glucose levels leads to the appearance of pathological signs that result in failures in the cardiovascular system and various diseases, such as diabetes, obesity, nephropathy, and neuropathy. Particularly, the brain relies on glucose as fuel for the normal development of neuronal activity. Regions adjacent to the cerebral ventricles, such as the hypothalamus and brainstem, exercise central control in energy homeostasis. These centers house nuclei of neurons whose excitatory activity is sensitive to changes in glucose levels. Determining the different detection mechanisms, the phenotype of neurosecretion, and neural connections involving glucose-sensitive neurons is essential to understanding the response to hypoglycemia through modulation of food intake, thermogenesis, and activation of sympathetic and parasympathetic branches, inducing glucagon and epinephrine secretion and other hypothalamic-pituitary axis-dependent counterregulatory hormones, such as glucocorticoids and growth hormone. The aim of this review focuses on integrating the current understanding of various glucose-sensing mechanisms described in the brain, thereby establishing a relationship between neuroanatomy and control of physiological processes involved in both metabolic and energy balance. This will advance the understanding of increasingly prevalent diseases in the modern world, especially diabetes, and emphasize patterns that regulate and stimulate intake, thermogenesis, and the overall synergistic effect of the neuroendocrine system.
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Affiliation(s)
- A J López-Gambero
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile.,Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, Málaga, Spain
| | - F Martínez
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - K Salazar
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - M Cifuentes
- Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, Málaga, Spain.
| | - F Nualart
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile. .,Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile.
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16
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Soengas JL, Cerdá-Reverter JM, Delgado MJ. Central regulation of food intake in fish: an evolutionary perspective. J Mol Endocrinol 2018; 60:R171-R199. [PMID: 29467140 DOI: 10.1530/jme-17-0320] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 02/21/2018] [Indexed: 12/11/2022]
Abstract
Evidence indicates that central regulation of food intake is well conserved along the vertebrate lineage, at least between teleost fish and mammals. However, several differences arise in the comparison between both groups. In this review, we describe similarities and differences between teleost fish and mammals on an evolutionary perspective. We focussed on the existing knowledge of specific fish features conditioning food intake, anatomical homologies and analogies between both groups as well as the main signalling pathways of neuroendocrine and metabolic nature involved in the homeostatic and hedonic central regulation of food intake.
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Affiliation(s)
- José Luis Soengas
- Departamento de Bioloxía Funcional e Ciencias da SaúdeLaboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - José Miguel Cerdá-Reverter
- Departamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - María Jesús Delgado
- Departamento de Fisiología (Fisiología Animal II)Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
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17
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Koekkoek LL, Mul JD, la Fleur SE. Glucose-Sensing in the Reward System. Front Neurosci 2017; 11:716. [PMID: 29311793 PMCID: PMC5742113 DOI: 10.3389/fnins.2017.00716] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 12/07/2017] [Indexed: 01/14/2023] Open
Abstract
Glucose-sensing neurons are neurons that alter their activity in response to changes in extracellular glucose. These neurons, which are an important mechanism the brain uses to monitor changes in glycaemia, are present in the hypothalamus, where they have been thoroughly investigated. Recently, glucose-sensing neurons have also been identified in brain nuclei which are part of the reward system. However, little is known about the molecular mechanisms by which they function, and their role in the reward system. We therefore aim to provide an overview of molecular mechanisms that have been studied in the hypothalamic glucose-sensing neurons, and investigate which of these transporters, enzymes and channels are present in the reward system. Furthermore, we speculate about the role of glucose-sensing neurons in the reward system.
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Affiliation(s)
- Laura L Koekkoek
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Laboratory of Endocrinology, Department of Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Metabolism and Reward Group, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, Netherlands
| | - Joram D Mul
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Laboratory of Endocrinology, Department of Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Metabolism and Reward Group, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, Netherlands
| | - Susanne E la Fleur
- Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Laboratory of Endocrinology, Department of Clinical Chemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Metabolism and Reward Group, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, Netherlands
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18
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van den Top M, Zhao FY, Viriyapong R, Michael NJ, Munder AC, Pryor JT, Renaud LP, Spanswick D. The impact of ageing, fasting and high-fat diet on central and peripheral glucose tolerance and glucose-sensing neural networks in the arcuate nucleus. J Neuroendocrinol 2017; 29. [PMID: 28834571 DOI: 10.1111/jne.12528] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 08/01/2017] [Accepted: 08/17/2017] [Indexed: 12/14/2022]
Abstract
Obesity and ageing are risk factors for diabetes. In the present study, we investigated the effects of ageing, obesity and fasting on central and peripheral glucose tolerance and on glucose-sensing neuronal function in the arcuate nucleus of rats, with a view to providing insight into the central mechanisms regulating glucose homeostasis and how they change or are subject to dysfunction with ageing and obesity. We show that, following a glucose load, central glucose tolerance at the level of the cerebrospinal fluid (CSF) and plasma is significantly reduced in rats maintained on a high-fat diet (HFD). With ageing, up to 2 years, central glucose tolerance was impaired in an age-dependent manner, whereas peripheral glucose tolerance remained unaffected. Ageing-induced peripheral glucose intolerance was improved by a 24-hour fast, whereas central glucose tolerance was not corrected. Pre-wean, immature animals have elevated basal plasma glucose levels and a delayed increase in central glucose levels following peripheral glucose injection compared to mature animals. Electrophysiological recording techniques revealed an energy-status-dependent role for glucose-excited, inhibited and adapting neurones, along with glucose-induced changes in synaptic transmission. We conclude that ageing affects central glucose tolerance, whereas HFD profoundly affects central and peripheral glucose tolerance and, in addition, glucose-sensing neurones adapt function in an energy-status-dependent manner.
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Affiliation(s)
| | - F-Y Zhao
- NeuroSolutions Ltd, Coventry, UK
| | - R Viriyapong
- Warwick Medical School, University of Warwick, Coventry, UK
- MOAC DTC, University of Warwick, Coventry, UK
| | - N J Michael
- Metabolic Disease and Obesity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Department of Physiology, Monash University, Clayton, VIC, Australia
| | - A C Munder
- Metabolic Disease and Obesity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Department of Physiology, Monash University, Clayton, VIC, Australia
| | - J T Pryor
- Warwick Medical School, University of Warwick, Coventry, UK
- Metabolic Disease and Obesity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Department of Physiology, Monash University, Clayton, VIC, Australia
| | - L P Renaud
- Ottawa Hospital Research Institute, Ottawa Civic Hospital, Ottawa, ON, Canada
| | - D Spanswick
- NeuroSolutions Ltd, Coventry, UK
- Warwick Medical School, University of Warwick, Coventry, UK
- Metabolic Disease and Obesity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Department of Physiology, Monash University, Clayton, VIC, Australia
- Neuroscience Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
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19
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Abstract
Glucokinase (GK), the hexokinase involved in glucosensing in pancreatic β-cells, is also expressed in arcuate nucleus (AN) neurons and hypothalamic tanycytes, the cells that surround the basal third ventricle (3V). Several lines of evidence suggest that tanycytes may be involved in the regulation of energy homeostasis. Tanycytes have extended cell processes that contact the feeding-regulating neurons in the AN, particularly, agouti-related protein (AgRP), neuropeptide Y (NPY), cocaine- and amphetamine-regulated transcript (CART) and proopiomelanocortin (POMC) neurons. In this study, we developed an adenovirus expressing GK shRNA to inhibit GK expression in vivo. When injected into the 3V of rats, this adenovirus preferentially transduced tanycytes. qRT-PCR and Western blot assays confirmed GK mRNA and protein levels were lower in GK knockdown animals compared to the controls. In response to an intracerebroventricular glucose injection, the mRNA levels of anorexigenic POMC and CART and orexigenic AgRP and NPY neuropeptides were altered in GK knockdown animals. Similarly, food intake, meal duration, frequency of eating events and the cumulative eating time were increased, whereas the intervals between meals were decreased in GK knockdown rats, suggesting a decrease in satiety. Thus, GK expression in the ventricular cells appears to play an important role in feeding behavior.
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20
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Horwath JA, Hurr C, Butler SD, Guruju M, Cassell MD, Mark AL, Davisson RL, Young CN. Obesity-induced hepatic steatosis is mediated by endoplasmic reticulum stress in the subfornical organ of the brain. JCI Insight 2017; 2:90170. [PMID: 28422749 PMCID: PMC5396512 DOI: 10.1172/jci.insight.90170] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 03/02/2017] [Indexed: 12/15/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD), characterized by an excess accumulation of hepatic triglycerides, is a growing health epidemic. While ER stress in the liver has been implicated in the development of NAFLD, the role of brain ER stress - which is emerging as a key contributor to a number of chronic diseases including obesity - in NAFLD remains unclear. These studies reveal that chemical induction of ER stress in the brain caused hepatomegaly and hepatic steatosis in mice. Conversely, pharmacological reductions in brain ER stress in diet-induced obese mice rescued NAFLD independent of body weight, food intake, and adiposity. Evaluation of brain regions involved revealed robust activation of ER stress biomarkers and ER ultrastructural abnormalities in the circumventricular subfornical organ (SFO), a nucleus situated outside of the blood-brain-barrier, in response to high-fat diet. Targeted reductions in SFO-ER stress in obese mice via SFO-specific supplementation of the ER chaperone 78-kDa glucose-regulated protein ameliorated hepatomegaly and hepatic steatosis without altering body weight, food intake, adiposity, or obesity-induced hypertension. Overall, these findings indicate a novel role for brain ER stress, notably within the SFO, in the pathogenesis of NAFLD.
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Affiliation(s)
- Julie A. Horwath
- Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, USA
| | - Chansol Hurr
- Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA
| | - Scott D. Butler
- Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Mallikarjun Guruju
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, USA
| | | | - Allyn L. Mark
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, USA
- Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Robin L. Davisson
- Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, USA
| | - Colin N. Young
- Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA
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21
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Shirakawa J, De Jesus DF, Kulkarni RN. Exploring inter-organ crosstalk to uncover mechanisms that regulate β-cell function and mass. Eur J Clin Nutr 2017; 71:896-903. [PMID: 28294170 DOI: 10.1038/ejcn.2017.13] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 01/24/2017] [Indexed: 02/07/2023]
Abstract
Impaired β-cell function and insufficient β-cell mass compensation are twin pathogenic features that underlie type 2 diabetes (T2D). Current therapeutic strategies continue to evolve to improve treatment outcomes in different ethnic populations and include approaches to counter insulin resistance and improve β-cell function. Although the effects of insulin secretion on metabolic organs such as liver, skeletal muscle and adipose is directly relevant for improving glucose uptake and reduce hyperglycemia, the ability of pancreatic β-cells to crosstalk with multiple non-metabolic tissues is providing novel insights into potential opportunities for improving β-cell function and/or mass that could have beneficial effects in patients with diabetes. For example, the role of the gastrointestinal system in the regulation of β-cell biology is well recognized and has been exploited clinically to develop incretin-related antidiabetic agents. The microbiome and the immune system are emerging as important players in regulating β-cell function and mass. The rich innervation of islet cells indicates it is a prime organ for regulation by the nervous system. In this review, we discuss the potential implications of signals from these organ systems as well as those from bone, placenta, kidney, thyroid, endothelial cells, reproductive organs and adrenal and pituitary glands that can directly impact β-cell biology. An added layer of complexity is the limited data regarding the relative relevance of one or more of these systems in different ethnic populations. It is evident that better understanding of this paradigm would provide clues to enhance β-cell function and/or mass in vivo in the long-term goal of treating or curing patients with diabetes.
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Affiliation(s)
- J Shirakawa
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| | - D F De Jesus
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA.,Graduate Program in Areas of Basic and Applied Biology (GABBA), Abel Salazar Biomedical Sciences Institute, University of Porto, Porto, Portugal
| | - R N Kulkarni
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
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22
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Conde-Sieira M, Soengas JL. Nutrient Sensing Systems in Fish: Impact on Food Intake Regulation and Energy Homeostasis. Front Neurosci 2017; 10:603. [PMID: 28111540 PMCID: PMC5216673 DOI: 10.3389/fnins.2016.00603] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 12/19/2016] [Indexed: 12/27/2022] Open
Abstract
Evidence obtained in recent years in a few species, especially rainbow trout, supports the presence in fish of nutrient sensing mechanisms. Glucosensing capacity is present in central (hypothalamus and hindbrain) and peripheral [liver, Brockmann bodies (BB, main accumulation of pancreatic endocrine cells in several fish species), and intestine] locations whereas fatty acid sensors seem to be present in hypothalamus, liver and BB. Glucose and fatty acid sensing capacities relate to food intake regulation and metabolism in fish. Hypothalamus is as a signaling integratory center in a way that detection of increased levels of nutrients result in food intake inhibition through changes in the expression of anorexigenic and orexigenic neuropeptides. Moreover, central nutrient sensing modulates functions in the periphery since they elicit changes in hepatic metabolism as well as in hormone secretion to counter-regulate changes in nutrient levels detected in the CNS. At peripheral level, the direct nutrient detection in liver has a crucial role in homeostatic control of glucose and fatty acid whereas in BB and intestine nutrient sensing is probably involved in regulation of hormone secretion from endocrine cells.
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Affiliation(s)
- Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo Vigo, Spain
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RNA-seq analysis of the hypothalamic transcriptome reveals the networks regulating physiopathological progress in the diabetic GK rat. Sci Rep 2016; 6:34138. [PMID: 27677945 PMCID: PMC5039700 DOI: 10.1038/srep34138] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 09/07/2016] [Indexed: 11/08/2022] Open
Abstract
The Goto-Kakizaki (GK) rat is an animal model of non-obese type 2 diabetes (T2D). The GK rat was generated through the introduction of various genetic mutations from continuous inbreeding; these rats develop diabetes spontaneously. The mutated genes in GK rats may play key roles in the regulation of diabetes. The hypothalamus plays a central role in systematic energy homeostasis. Here, the hypothalamic transcriptomes in GK and Wistar rats at 4, 8 and 12 weeks were investigated by RNA-seq, and multiple variants and gene expression profiles were obtained. The number of variants identified from GK rats was significantly greater than that of Wistar rats, indicating that many variants were fixed and heritable in GK rats after selective inbreeding. The differential gene expression analysis indicated that GK rats had a dysfunctional hypothalamic melanocortin system and attenuation of the hypothalamic glucose-sensing pathway. In addition, we generated integrated gene network modules by combining the protein-protein interaction (PPI) network, co-expression network and mutations in GK and Wistar rats. In the modules, GK-specific genes, such as Bad, Map2k2, Adcy3, Adcy2 and Gstm6, may play key roles in hypothalamic regulation in GK rats. Our research provides a comprehensive map of the abnormalities in the GK rat hypothalamus, which reveals the new mechanisms of pathogenesis of T2D.
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Rosario W, Singh I, Wautlet A, Patterson C, Flak J, Becker TC, Ali A, Tamarina N, Philipson LH, Enquist LW, Myers MG, Rhodes CJ. The Brain-to-Pancreatic Islet Neuronal Map Reveals Differential Glucose Regulation From Distinct Hypothalamic Regions. Diabetes 2016; 65:2711-23. [PMID: 27207534 PMCID: PMC5001176 DOI: 10.2337/db15-0629] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 04/06/2016] [Indexed: 12/24/2022]
Abstract
The brain influences glucose homeostasis, partly by supplemental control over insulin and glucagon secretion. Without this central regulation, diabetes and its complications can ensue. Yet, the neuronal network linking to pancreatic islets has never been fully mapped. Here, we refine this map using pseudorabies virus (PRV) retrograde tracing, indicating that the pancreatic islets are innervated by efferent circuits that emanate from the hypothalamus. We found that the hypothalamic arcuate nucleus (ARC), ventromedial nucleus (VMN), and lateral hypothalamic area (LHA) significantly overlap PRV and the physiological glucose-sensing enzyme glucokinase. Then, experimentally lowering glucose sensing, specifically in the ARC, resulted in glucose intolerance due to deficient insulin secretion and no significant effect in the VMN, but in the LHA it resulted in a lowering of the glucose threshold that improved glucose tolerance and/or improved insulin sensitivity, with an exaggerated counter-regulatory response for glucagon secretion. No significant effect on insulin sensitivity or metabolic homeostasis was noted. Thus, these data reveal novel direct neuronal effects on pancreatic islets and also render a functional validation of the brain-to-islet neuronal map. They also demonstrate that distinct regions of the hypothalamus differentially control insulin and glucagon secretion, potentially in partnership to help maintain glucose homeostasis and guard against hypoglycemia.
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Affiliation(s)
- Wilfredo Rosario
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
| | - Inderroop Singh
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
| | - Arnaud Wautlet
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
| | - Christa Patterson
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI
| | - Jonathan Flak
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI
| | - Thomas C Becker
- Duke Molecular Physiology Institute and Sarah W. Stedman Nutrition and Metabolism Center, Duke University, Durham, NC
| | - Almas Ali
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
| | - Natalia Tamarina
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
| | - Louis H Philipson
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
| | - Lynn W Enquist
- Department of Molecular Biology, Princeton University, Princeton, NJ
| | - Martin G Myers
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI
| | - Christopher J Rhodes
- Kovler Diabetes Center, Department of Medicine, Section of Endocrinology, Diabetes and Metabolism, University of Chicago, Chicago, IL
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Park S, Kang S, Jeong DY, Jeong SY, Kim MJ. Black carrots fermented with Lactobacillus plantarum or Aspergillus oryzae prevent cognitive dysfunction by improving hippocampal insulin signalling in amyloid-β infused rats. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.06.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Heeley N, Blouet C. Central Amino Acid Sensing in the Control of Feeding Behavior. Front Endocrinol (Lausanne) 2016; 7:148. [PMID: 27933033 PMCID: PMC5120084 DOI: 10.3389/fendo.2016.00148] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 11/03/2016] [Indexed: 11/13/2022] Open
Abstract
Dietary protein quantity and quality greatly impact metabolic health via evolutionary-conserved mechanisms that ensure avoidance of amino acid imbalanced food sources, promote hyperphagia when dietary protein density is low, and conversely produce satiety when dietary protein density is high. Growing evidence supports the emerging concept of protein homeostasis in mammals, where protein intake is maintained within a tight range independently of energy intake to reach a target protein intake. The behavioral and neuroendocrine mechanisms underlying these adaptations are unclear. While peripheral factors are able to signal amino acid deficiency and abundance to the brain, the brain itself is exposed to and can detect changes in amino acid concentrations, and subsequently engages acute and chronic responses modulating feeding behavior and food preferences. In this review, we will examine the literature describing the mechanisms by which the brain senses changes in amino acids concentrations, and how these changes modulate feeding behavior.
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Affiliation(s)
- Nicholas Heeley
- Medical Research Council Metabolic Disease Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Clemence Blouet
- Medical Research Council Metabolic Disease Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK
- *Correspondence: Clemence Blouet,
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Glucose and hypothalamic astrocytes: More than a fueling role? Neuroscience 2015; 323:110-20. [PMID: 26071958 DOI: 10.1016/j.neuroscience.2015.06.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 06/02/2015] [Accepted: 06/04/2015] [Indexed: 01/19/2023]
Abstract
Brain plays a central role in energy homeostasis continuously integrating numerous peripheral signals such as circulating nutrients, and in particular blood glucose level, a variable that must be highly regulated. Then, the brain orchestrates adaptive responses to modulate food intake and peripheral organs activity in order to achieve the fine tuning of glycemia. More than fifty years ago, the presence of glucose-sensitive neurons was discovered in the hypothalamus, but what makes them specific and identifiable still remains disconnected from their electrophysiological signature. On the other hand, astrocytes represent the major class of macroglial cells and are now recognized to support an increasing number of neuronal functions. One of these functions consists in the regulation of energy homeostasis through neuronal fueling and nutrient sensing. Twenty years ago, we discovered that the glucose transporter GLUT2, the canonical "glucosensor" of the pancreatic beta-cell together with the glucokinase, was also present in astrocytes and participated in hypothalamic glucose sensing. Since then, many studies have identified other actors and emphasized the astroglial participation in this mechanism. Growing evidence suggest that astrocytes form a complex network and have to be considered as spatially coordinated and regulated metabolic units. In this review we aim to provide an updated view of the molecular and respective cellular pathways involved in hypothalamic glucose sensing, and their relevance in physiological and pathological states.
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Nutrient-sensing mechanisms and pathways. Nature 2015; 517:302-10. [PMID: 25592535 DOI: 10.1038/nature14190] [Citation(s) in RCA: 730] [Impact Index Per Article: 81.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 12/02/2014] [Indexed: 12/14/2022]
Abstract
The ability to sense and respond to fluctuations in environmental nutrient levels is a requisite for life. Nutrient scarcity is a selective pressure that has shaped the evolution of most cellular processes. Different pathways that detect intracellular and extracellular levels of sugars, amino acids, lipids and surrogate metabolites are integrated and coordinated at the organismal level through hormonal signals. During food abundance, nutrient-sensing pathways engage anabolism and storage, whereas scarcity triggers homeostatic mechanisms, such as the mobilization of internal stores through autophagy. Nutrient-sensing pathways are commonly deregulated in human metabolic diseases.
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