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Kim EJ, Jeong HS, Kwon E, Jeong SH, Kim JS. Muscle mass and chronic dizziness: a cross-sectional study of a Korean population. J Neurol 2024; 271:1213-1223. [PMID: 37910251 DOI: 10.1007/s00415-023-12014-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 09/15/2023] [Accepted: 09/16/2023] [Indexed: 11/03/2023]
Abstract
BACKGROUND AND OBJECTIVES Weight gain is associated with imbalance in older people. In contrast, overweightness or mild obesity is less common in patients with chronic dizziness. This paradox may be, at least in part, related to differences in the body composition indices adopted in the previous studies. This study aimed to determine any association between the predicted body composition and chronic dizziness or imbalance of unknown causes. METHODS We measured the lean body mass, body fat mass, and appendicular skeletal mass in 9243 people who participated in the Korean National Health and Nutrition Examination Survey 2019-2021. Sarcopenia was defined according to the Asian Working Group for Sarcopenia's guidelines. Obesity was defined as a body fat percentage of ≥ 25% for men and ≥ 35% for women. RESULTS The participants with chronic dizziness had a lower body mass index than those without (p = 0.001). Furthermore, sarcopenia was more common in those with chronic dizziness. In contrast, the degree of obesity was comparable in both groups. Multiple logistic regression analysis showed that sarcopenia was associated with a higher risk of chronic dizziness (odds ratio = 1.6, 95% confidence interval: 1.1-2.5; p = 0.026). DISCUSSION Given the association of sarcopenia with chronic dizziness or imbalance, muscle mass may play a role in maintaining balance and stability. Physical exercise could be recommended to increase muscle mass in patients with chronic dizziness/imbalance and sarcopenia. Additional research is required to establish a causal relationship between chronic dizziness and sarcopenia.
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Affiliation(s)
- Eun Ji Kim
- Department of Neurology, Chungnam National University Hospital, Daejeon, Korea
| | - Hye Seon Jeong
- Department of Neurology, Chungnam National University Hospital, Daejeon, Korea
| | - Eunjin Kwon
- Department of Neurology, Chungnam National University Hospital, Daejeon, Korea
| | - Seong-Hae Jeong
- Department of Neurology, Chungnam National University Hospital, Daejeon, Korea.
- Department of Neurology, Chungnam National University Hospital, Chungnam National University School of Medicine, 282 Munhwa-ro, Jung-gu, Daejeon, 35015, Korea.
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul, Korea
- Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea
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Huang L, Deng X, Yang X, Tang Z, Fan S, Zhou Z, Tao M, Liu S. Cloning, distribution, and effects of growth regulation of MC3R and MC4R in red crucian carp ( Carassius auratus red var.). Front Endocrinol (Lausanne) 2024; 14:1310000. [PMID: 38322156 PMCID: PMC10846643 DOI: 10.3389/fendo.2023.1310000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 12/27/2023] [Indexed: 02/08/2024] Open
Abstract
Background Melanocortin-3 and -4 receptors (MC3R and MC4R), G protein-coupled receptors, play vital roles in the regulation of energy homeostasis. To understand the functions of mc3r and mc4r in the energy homeostasis of red crucian carp (Carassius auratus red var., RCC), we cloned mc3r and mc4r, analyzed the tissue expression and localization of the genes, and investigated the effects of knockout of mc3r (mc3r +/-) and mc4r (mc4r +/-) in RCC. Results The full-length cDNAs of RCC mc3r and mc4r were 1459 base pairs (bp) and 1894 bp, respectively. qRT-PCR indicated that mc3r and mc4r were profusely expressed in the brain, but lower expressed in the periphery tissues. ISH revealed that mc3r and mc4r were located in NPP, NPO, NAPv, NSC, NAT, NRL, NLTl, and NLTp of the brain, suggesting that mc3r and mc4r might regulate many physiological and behavioral aspects in RCC. To further verify the roles of mc3r and mc4r in energy homeostasis, the mc3r+/- and mc4r+/- fish were obtained by the CRISPR/Cas9 system. The average body weights, total lengths, body depths, and food intake of mc4r+/- fish were significantly higher than those of mc3r+/- and the normal wild-type (WT) fish, but there was no difference between the mc3r+/- and WT fish, indicating that the RCC phenotype and food intake were mainly influenced by mc4r but not mc3r. Interestingly, mc4r+/- fish displayed more visceral fat mass than mc3r+/- and WT fish, and mc3r+/- fish also exhibited slightly more visceral fat mass compared to WT. RNA-seq of the liver and muscle revealed that a large number of differentially expressed genes (DEGs) differed in WT vs. mc3r+/-, WT vs. mc4r+/-, and mc3r+/- vs. mc4r+/-, mainly related to lipid, glucose, and energy metabolism. The KEGG enrichment analysis revealed that DEGs were mainly enriched in pathways such as steroid biosynthesis, fatty acid metabolism, fatty acid biosynthesis, glycolysis/gluconeogenesis, wnt signaling pathway, PPAR signaling pathway, and MAPK signaling pathway, thereby affecting lipid accumulation and growth. Conclusion In conclusion, these results will assist in the further investigation of the molecular mechanisms in which MC3R and MC4R were involved in the regulation of energy homeostasis in fish.
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Affiliation(s)
| | | | | | | | | | | | - Min Tao
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, Hunan, China
| | - Shaojun Liu
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, Hunan, China
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Choi J, Kim S, Kim J, Son HY, Yoo SK, Kim CU, Park YJ, Moon S, Cha B, Jeon MC, Park K, Yun JM, Cho B, Kim N, Kim C, Kwon NJ, Park YJ, Matsuda F, Momozawa Y, Kubo M, Kim HJ, Park JH, Seo JS, Kim JI, Im SW. A whole-genome reference panel of 14,393 individuals for East Asian populations accelerates discovery of rare functional variants. SCIENCE ADVANCES 2023; 9:eadg6319. [PMID: 37556544 PMCID: PMC10411914 DOI: 10.1126/sciadv.adg6319] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 07/06/2023] [Indexed: 08/11/2023]
Abstract
Underrepresentation of non-European (EUR) populations hinders growth of global precision medicine. Resources such as imputation reference panels that match the study population are necessary to find low-frequency variants with substantial effects. We created a reference panel consisting of 14,393 whole-genome sequences including more than 11,000 Asian individuals. Genome-wide association studies were conducted using the reference panel and a population-specific genotype array of 72,298 subjects for eight phenotypes. This panel yields improved imputation accuracy of rare and low-frequency variants within East Asian populations compared with the largest reference panel. Thirty-nine previously unidentified associations were found, and more than half of the variants were East Asian specific. We discovered genes with rare protein-altering variants, including LTBP1 for height and GPR75 for body mass index, as well as putative regulatory mechanisms for rare noncoding variants with cell type-specific effects. We suggest that this dataset will add to the potential value of Asian precision medicine.
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Affiliation(s)
- Jaeyong Choi
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | | | - Juhyun Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ho-Young Son
- Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| | - Seong-Keun Yoo
- The Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Young Jun Park
- Department of Translational Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sungji Moon
- Interdisciplinary Program in Cancer Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Cancer Research Institute, Seoul National University, Seoul, Republic of Korea
| | - Bukyoung Cha
- Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| | - Min Chul Jeon
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyunghyuk Park
- Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| | - Jae Moon Yun
- Department of Family Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Belong Cho
- Department of Family Medicine, Seoul National University Hospital, Seoul, Republic of Korea
- Department of Family Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | | | | | | | - Young Joo Park
- Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, Republic of Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea
| | - Fumihiko Matsuda
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | | | - Michiaki Kubo
- RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | | | - Hyun-Jin Kim
- National Cancer Control Institute, National Cancer Center, Goyang, Republic of Korea
| | - Jin-Ho Park
- Department of Family Medicine, Seoul National University Hospital, Seoul, Republic of Korea
- Department of Family Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jeong-Sun Seo
- Macrogen Inc., Seoul, Republic of Korea
- Asian Genome Center, Seoul National University Bundang Hospital, Gyeonggi, Republic of Korea
| | - Jong-Il Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
- Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, Republic of Korea
- Cancer Research Institute, Seoul National University, Seoul, Republic of Korea
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sun-Wha Im
- Department of Biochemistry and Molecular Biology, Kangwon National University School of Medicine, Gangwon, Republic of Korea
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The Association of the Hypothalamic-Pituitary-Adrenal Axis with Appetite Regulation in Children with Fetal Alcohol Spectrum Disorders (FASDs). Nutrients 2023; 15:nu15061366. [PMID: 36986097 PMCID: PMC10053353 DOI: 10.3390/nu15061366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 03/14/2023] Open
Abstract
Prenatal alcohol exposure causes growth impairment and a wide range of developmental, physical, and cognitive disorders in children, collectively referred to as fetal alcohol spectrum disorders (FASDs). In the course of FASDs, abnormalities can also affect eating behavior and nutritional status, but these problems have received little attention. Therefore, the aim of our study was to determine the levels of hormones involved in the action of the hypothalamic–pituitary–adrenal axis: proopiomelanocortin (POMC), cortisol, and adrenocorticotropic hormone (ACTH), in the serum of patients with FASDs. To our knowledge, none of these hormones studied have yet been evaluated in FASDs to date. We investigated 62 FASD patients and 23 healthy controls by applying an enzyme-linked immunosorbent method (ELISA). Fasting POMC levels were significantly lower in patients with FASDs (10.97 vs. 18,57 ng/mL, p = 0.039) compared to controls. However, there were no differences in cortisol concentrations. Additionally, the sex and subgroup status (fetal alcohol syndrome (FAS), neurobehavioral disorder associated with prenatal alcohol exposure (ND-PAE), and FASD risk) did not affect hormone levels. POMC was positively correlated with some clinical parameters such as age, BMI percentile, carbohydrate biomarkers, and ACTH. A positive correlation was observed between ACTH and cortisol levels, as well as ACTH and cholesterol levels. Data analysis showed no HPA axis abnormalities in the form of elevated serum cortisol and ACTH levels. Differences in POMC concentration may indicate the involvement and/or impairment of central nervous system structures in hormonal alterations in FASD individuals, caused by prenatal alcohol exposure. Hormonal dysregulation in FASDs can contribute to reduced growth and development, as well as many other disturbed processes, including neurological/neurodevelopmental dysfunctions. Further insightful studies involving a larger group of patients are needed to determine the potential impact of the measured hormones.
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Abstract
Brown adipose tissue (BAT) displays the unique capacity to generate heat through uncoupled oxidative phosphorylation that makes it a very attractive therapeutic target for cardiometabolic diseases. Here, we review BAT cellular metabolism, its regulation by the central nervous and endocrine systems and circulating metabolites, the plausible roles of this tissue in human thermoregulation, energy balance, and cardiometabolic disorders, and the current knowledge on its pharmacological stimulation in humans. The current definition and measurement of BAT in human studies relies almost exclusively on BAT glucose uptake from positron emission tomography with 18F-fluorodeoxiglucose, which can be dissociated from BAT thermogenic activity, as for example in insulin-resistant states. The most important energy substrate for BAT thermogenesis is its intracellular fatty acid content mobilized from sympathetic stimulation of intracellular triglyceride lipolysis. This lipolytic BAT response is intertwined with that of white adipose (WAT) and other metabolic tissues, and cannot be independently stimulated with the drugs tested thus far. BAT is an interesting and biologically plausible target that has yet to be fully and selectively activated to increase the body's thermogenic response and shift energy balance. The field of human BAT research is in need of methods able to directly, specifically, and reliably measure BAT thermogenic capacity while also tracking the related thermogenic responses in WAT and other tissues. Until this is achieved, uncertainty will remain about the role played by this fascinating tissue in human cardiometabolic diseases.
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Affiliation(s)
- André C Carpentier
- Correspondence: André C. Carpentier, MD, Division of Endocrinology, Faculty of Medicine, University of Sherbrooke, 3001, 12th Ave N, Sherbrooke, Quebec, J1H 5N4, Canada.
| | - Denis P Blondin
- Division of Neurology, Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, J1H 5N4, Canada
| | | | - Denis Richard
- Centre de recherche de l’Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Quebec City, Quebec, G1V 4G5, Canada
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Yu HX, Li Y, Zhong DB, Ren X, Mo HL, Jiang ZB, Yu JJ, Xiong DM, Liu HX, Wang LX. The interaction of MC3R and MC4R with MRAP2a in rainbow trout (Oncorhynchus mykiss). FISH PHYSIOLOGY AND BIOCHEMISTRY 2023; 49:61-74. [PMID: 36525144 DOI: 10.1007/s10695-022-01159-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Melanocortin 3 and 4 receptors are two important neural G protein-coupled receptors that regulate energy homeostasis in vertebrates. Melanocortin receptor accessory protein 2 (MRAP2) is also involved in the regulation of food intake and body weight as a variable regulator of melanocortin receptors. Rainbow trout (Oncorhynchus mykiss) is a valuable cold-water fish cultured worldwide. In the rainbow trout model, we cloned and identified mrap2a, a paralog of mrap2. Rainbow trout mrap2a consisted of a 690 bp ORF and was expected to encode a putative protein of 229 amino acids. The qPCR results showed that rainbow trout mrap2a was expressed at high levels in brain tissue similar to mc3r and mc4r. In addition, co-immunoprecipitation verified that MRAP2a interacts with MC3R and MC4R in vitro and that MRAP2a is involved in and regulates the constitutive activity and signaling of MC3R and MC4R. MRAP2a reduced constitutive and agonist-stimulated cAMP levels of MC3R; furthermore, MRAP2a increased constitutive ERK1/2 activation but reduced ligand-induced stimulation at high levels of expression. For MC4R, MRAP2a showed decreased cAMP basal activity but increased agonist-stimulated cAMP signaling and increased ACTH ligand sensitivity. However, MRAP2a failed to affect MC4R constitutive activity and agonist-induced ERK1/2 signaling. Undoubtedly, our study will have great significance for revealing the conserved role of MC4R and MC3R signaling in teleost fish, especially in cold-water fish growth and energy homeostasis.
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Affiliation(s)
- Hui-Xia Yu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yang Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - De-Bin Zhong
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xin Ren
- Meixian Aquaculture Farm of Shitouhe Reservoir Administration, Xianyang, 712000, Shaanxi, China
| | - Hao-Lin Mo
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Ze-Bin Jiang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jia-Jia Yu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Dong-Mei Xiong
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Hai-Xia Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Li-Xin Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Bedenbaugh MN, Brener SC, Maldonado J, Lippert RN, Sweeney P, Cone RD, Simerly RB. Organization of neural systems expressing melanocortin-3 receptors in the mouse brain: Evidence for sexual dimorphism. J Comp Neurol 2022; 530:2835-2851. [PMID: 35770983 PMCID: PMC9724692 DOI: 10.1002/cne.25379] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 01/13/2023]
Abstract
The central melanocortin system is fundamentally important for controlling food intake and energy homeostasis. Melanocortin-3 receptor (MC3R) is one of two major receptors of the melanocortin system found in the brain. In contrast to the well-characterized melanocortin-4 receptor (MC4R), little is known regarding the organization of MC3R-expressing neural circuits. To increase our understanding of the intrinsic organization of MC3R neural circuits, identify specific differences between males and females, and gain a neural systems level perspective of this circuitry, we conducted a brain-wide mapping of neurons labeled for MC3R and characterized the distribution of their projections. Analysis revealed MC3R neuronal and terminal labeling in multiple brain regions that control a diverse range of physiological functions and behavioral processes. Notably, dense labeling was observed in the hypothalamus, as well as areas that share considerable connections with the hypothalamus, including the cortex, amygdala, thalamus, and brainstem. Additionally, MC3R neuronal labeling was sexually dimorphic in several areas, including the anteroventral periventricular area, arcuate nucleus, principal nucleus of the bed nucleus of the stria terminalis, and ventral premammillary region. Altogether, anatomical evidence reported here suggests that MC3R has the potential to influence several different classes of motivated behavior that are essential for survival, including ingestive, reproductive, defensive, and arousal behaviors, and is likely to modulate these behaviors differently in males and females.
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Affiliation(s)
- Michelle N. Bedenbaugh
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - Samantha C. Brener
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - Jose Maldonado
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - Rachel N. Lippert
- Department of Neurocircuit Development and Function, German Institute of Human Nutrition Potsdam-Rehbruecke, Potsdam, Germany
| | - Patrick Sweeney
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Roger D. Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Richard B. Simerly
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
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Dunigan AI, Roseberry AG. Actions of feeding-related peptides on the mesolimbic dopamine system in regulation of natural and drug rewards. ADDICTION NEUROSCIENCE 2022; 2:100011. [PMID: 37220637 PMCID: PMC10201992 DOI: 10.1016/j.addicn.2022.100011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The mesolimbic dopamine system is the primary neural circuit mediating motivation, reinforcement, and reward-related behavior. The activity of this system and multiple behaviors controlled by it are affected by changes in feeding and body weight, such as fasting, food restriction, or the development of obesity. Multiple different peptides and hormones that have been implicated in the control of feeding and body weight interact with the mesolimbic dopamine system to regulate many different dopamine-dependent, reward-related behaviors. In this review, we summarize the effects of a selected set of feeding-related peptides and hormones acting within the ventral tegmental area and nucleus accumbens to alter feeding, as well as food, drug, and social reward.
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Affiliation(s)
- Anna I. Dunigan
- Department of Biology and Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Aaron G. Roseberry
- Department of Biology and Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
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Transcriptome Sequencing Analysis Reveals Dynamic Changes in Major Biological Functions during the Early Development of Clearhead Icefish, Protosalanx chinensis. FISHES 2022. [DOI: 10.3390/fishes7030115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Early development, when many important developmental events occur, is a critical period for fish. However, research on the early development of clearhead icefish is very limited, especially in molecular research. In this study, we aimed to explore the dynamic changes in the biological functions of five key periods in clearhead icefish early development, namely the YL (embryonic), PM (first day after hatching), KK (fourth day after hatching), LC (seventh day after hatching), and SL (tenth day after hatching) stages, through transcriptome sequencing and different analysis strategies. A trend expression analysis and an enrichment analysis revealed that the expression ofgenes encoding G protein-coupled receptors and their ligands, i.e., prss1_2_3, pomc, npy, npb, sst, rln3, crh, gh, and prl that are associated with digestion and feeding regulation gradually increased during early development. In addition, a weighted gene co-expression network analysis (WGCNA) showed that eleven modules were significantly associated with early development, among which nine modules were significantly positively correlated. Through the enrichment analysis and hub gene identification results of these nine modules, it was found that the pathways related to eye, bone, and heart development were significantly enriched in the YL stage, and the ccnd2, seh1l, kdm6a, arf4, and ankrd28 genes that are associated with cell proliferation and differentiation played important roles in these developmental processes; the pak3, dlx3, dgat2, and tas1r1 genes that are associated with jaw and tooth development, TG (triacylglycerol) synthesis, and umami amino acid receptors were identified as hub genes for the PM stage; the pathways associated with aerobic metabolism and unsaturated fatty acid synthesis were significantly enriched in the KK stage, with the foxk, slc13a2_3_5, ndufa5, and lsc2 genes playing important roles; the pathways related to visual perception were significantly enriched in the LC stage; and the bile acid biosynthetic and serine-type peptidase activity pathways were significantly enriched in the SL stage. These results provide a more detailed understanding of the processes of early development of clearhead icefish.
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Oliveira LDC, Morais GP, Ropelle ER, de Moura LP, Cintra DE, Pauli JR, de Freitas EC, Rorato R, da Silva ASR. Using Intermittent Fasting as a Non-pharmacological Strategy to Alleviate Obesity-Induced Hypothalamic Molecular Pathway Disruption. Front Nutr 2022; 9:858320. [PMID: 35445066 PMCID: PMC9014844 DOI: 10.3389/fnut.2022.858320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/25/2022] [Indexed: 12/18/2022] Open
Abstract
Intermittent fasting (IF) is a popular intervention used to fight overweight/obesity. This condition is accompanied by hypothalamic inflammation, limiting the proper signaling of molecular pathways, with consequent dysregulation of food intake and energy homeostasis. This mini-review explored the therapeutic modulation potential of IF regarding the disruption of these molecular pathways. IF seems to modulate inflammatory pathways in the brain, which may also be correlated with the brain-microbiota axis, improving hypothalamic signaling of leptin and insulin, and inducing the autophagic pathway in hypothalamic neurons, contributing to weight loss in obesity. Evidence also suggests that when an IF protocol is performed without respecting the circadian cycle, it can lead to dysregulation in the expression of circadian cycle regulatory genes, with potential health damage. In conclusion, IF may have the potential to be an adjuvant treatment to improve the reestablishment of hypothalamic responses in obesity.
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Affiliation(s)
- Luciana da Costa Oliveira
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
| | - Gustavo Paroschi Morais
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
| | - Eduardo R. Ropelle
- Laboratory of Molecular Biology of Exercise, School of Applied Sciences, University of Campinas, São Paulo, Brazil
| | - Leandro P. de Moura
- Laboratory of Molecular Biology of Exercise, School of Applied Sciences, University of Campinas, São Paulo, Brazil
| | - Dennys E. Cintra
- Laboratory of Molecular Biology of Exercise, School of Applied Sciences, University of Campinas, São Paulo, Brazil
| | - José R. Pauli
- Laboratory of Molecular Biology of Exercise, School of Applied Sciences, University of Campinas, São Paulo, Brazil
| | - Ellen C. de Freitas
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
| | - Rodrigo Rorato
- Postgraduate Program in Molecular Biology, Laboratory of Stress Neuroendocrinology, Department of Biophysics, Paulista Medical School, Federal University of São Paulo, São Paulo, Brazil
- Rodrigo Rorato,
| | - Adelino Sanchez R. da Silva
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
- *Correspondence: Adelino Sanchez R. da Silva,
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11
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Jiang H, Zhang W, Li X, Xu Y, Cao J, Jiang W. The anti-obesogenic effects of dietary berry fruits: A review. Food Res Int 2021; 147:110539. [PMID: 34399516 DOI: 10.1016/j.foodres.2021.110539] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 05/23/2021] [Accepted: 06/15/2021] [Indexed: 02/06/2023]
Abstract
The prevalence of obesity in the world is fearsomely climbing, which has brought about heavy threats on human health and economic development. For coping with this problem, researchers have looked at the profound potentials of natural products for resolving obesity because of their high efficiencies and few undesirable outcomes in the recent years. Berry fruits are huge reservoirs of bioactive components, and their anti-obesity potentials are arousing much interests. In this review, the current main strategies to manage obesity were summarized, including inhibiting appetite and lowering the food intake, improving energy expenditure and thermogenesis, suppressing absorption and digestion, reducing lipid synthesis and storage as well as modulating composition of gut microbiota. In addition, this review discussed the potentials of dietary berry fruits (blueberries, cranberries, raspberries, strawberries, mulberries, lingonberries, blackberries, black chokeberries, elderberries, bilberries, grape, blackcurrants, jaboticabas, red bayberries, sea-buckthorns, goldenberries and goji berries) to counteract obesity or obesity-associated complications based on recent animal experiments and human studies. Then, the bioaccessibility of phenolic compounds present in berry fruits was discussed. On the other hand, several challenges including securing effective dosage, further understanding their interaction with human tissues, improving bioavailability and protection of functional ingredients during delivery should be taken into account and conquered in the coming years.
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Affiliation(s)
- Haitao Jiang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Wanli Zhang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Xiangxin Li
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Yan Xu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Jiankang Cao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Weibo Jiang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China.
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12
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Micioni Di Bonaventura E, Botticelli L, Tomassoni D, Tayebati SK, Micioni Di Bonaventura MV, Cifani C. The Melanocortin System behind the Dysfunctional Eating Behaviors. Nutrients 2020; 12:E3502. [PMID: 33202557 PMCID: PMC7696960 DOI: 10.3390/nu12113502] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/09/2020] [Accepted: 11/11/2020] [Indexed: 12/11/2022] Open
Abstract
The dysfunction of melanocortin signaling has been associated with obesity, given the important role in the regulation of energy homeostasis, food intake, satiety and body weight. In the hypothalamus, the melanocortin-3 receptor (MC3R) and melanocortin-4 receptor (MC4R) contribute to the stability of these processes, but MC3R and MC4R are also localized in the mesolimbic dopamine system, the region that responds to the reinforcing properties of highly palatable food (HPF) and where these two receptors seem to affect food reward and motivation. Loss of function of the MC4R, resulting from genetic mutations, leads to overeating in humans, but to date, a clear understanding of the underlying mechanisms and behaviors that promote overconsumption of caloric foods remains unknown. Moreover, the MC4R demonstrated to be a crucial modulator of the stress response, factor that is known to be strictly related to binge eating behavior. In this review, we will explore the preclinical and clinical studies, and the controversies regarding the involvement of melanocortin system in altered eating patterns, especially binge eating behavior, food reward and motivation.
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Affiliation(s)
| | - Luca Botticelli
- School of Pharmacy, University of Camerino, 62032 Camerino, Italy; (E.M.D.B.); (L.B.); (S.K.T.); (C.C.)
| | - Daniele Tomassoni
- School of Bioscience and Veterinary Medicine, University of Camerino, 62032 Camerino, Italy;
| | - Seyed Khosrow Tayebati
- School of Pharmacy, University of Camerino, 62032 Camerino, Italy; (E.M.D.B.); (L.B.); (S.K.T.); (C.C.)
| | | | - Carlo Cifani
- School of Pharmacy, University of Camerino, 62032 Camerino, Italy; (E.M.D.B.); (L.B.); (S.K.T.); (C.C.)
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13
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Sun B, Vatanen T, Jayasinghe TN, McKenzie E, Murphy R, O'Sullivan JM. Desacetyl-α-MSH and α-MSH have sex specific interactions with diet to influence mouse gut morphology, metabolites and microbiota. Sci Rep 2020; 10:18957. [PMID: 33144604 PMCID: PMC7641164 DOI: 10.1038/s41598-020-75786-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 10/15/2020] [Indexed: 12/11/2022] Open
Abstract
The melanocortin peptides have an important role in regulating body weight and appetite. Mice that lack the desacetyl-α-MSH and α-MSH peptides (Pomctm1/tm1) develop obesity. This effect is exacerbated by a high fat diet (HFD). However, development of obesity in female Pomctm1/tm1 mice during chronic HFD conditions is not fully accounted for by the increased energy intake. We hypothesized that the protection against chronic HFD-induced obesity imparted by MSH peptides in females is mediated by sex-specific alterations in the gut structure and gut microbiota. We determined that female WT mice had reduced jejunum villus length and increased crypt depth in response to chronic HFD. WT males and Pomctm1/tm1 mice lacked this adaptation to a chronic HFD. Both Pomctm1/tm1 genotype and chronic HFD were significantly associated with gut microbiota composition. Sex-specific associations between Pomctm1/tm1 genotype and gut microbiota were observed in the presence of a chronic HFD. Pomctm1/tm1 females had significantly reduced fecal acetate and propionate concentrations when compared to WT females. We conclude that MSH peptides influence jejunum villus length, crypt depth and the structure of the gut microbiota. These effects favor reduced nutrient absorption and occur in addition to the recognized roles of desacetyl-α-MSH and α-MSH peptides in appetite control.
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Affiliation(s)
- Bo Sun
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Tommi Vatanen
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand
| | - Thilini N Jayasinghe
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand
| | - Elizabeth McKenzie
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand
| | - Rinki Murphy
- School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
- Department of Medicine, Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand.
| | - Justin M O'Sullivan
- The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand.
- Department of Medicine, Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, 85 Park Road, Grafton, Auckland, 1142, New Zealand.
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14
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Lebrun B, Barbot M, Tonon MC, Prévot V, Leprince J, Troadec JD. Glial endozepines and energy balance: Old peptides with new tricks. Glia 2020; 69:1079-1093. [PMID: 33105065 DOI: 10.1002/glia.23927] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/09/2020] [Accepted: 10/09/2020] [Indexed: 12/12/2022]
Abstract
The contribution of neuroglial interactions to the regulation of energy balance has gained increasing acceptance in recent years. In this context, endozepines, endogenous analogs of benzodiazepine derived from diazepam-binding inhibitor, are now emerging as major players. Produced by glial cells (astrocytes and tanycytes), endozepines have been known for two decades to exert potent anorexigenic effects by acting at the hypothalamic level. However, it is only recently that their modes of action, including the mechanisms by which they modulate energy metabolism, have begun to be elucidated. The data available today are abundant, significant, and sometimes contradictory, revealing a much more complex regulation than initially expected. Several mechanisms of action of endozepines seem to coexist at the central level, particularly in the hypothalamus. The brainstem has also recently emerged as a potential site of action for endozepines. In addition to their central anorexigenic effects, endozepines may also display peripheral effects promoting orexigenic actions, adding to their complexity and raising yet more questions. In this review, we attempt to provide an overview of our current knowledge in this rapidly evolving field and to pinpoint questions that remain unanswered.
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Affiliation(s)
- Bruno Lebrun
- CNRS 7291, Laboratoire de Neurosciences Cognitives, Aix Marseille University, Marseille, France
| | - Manon Barbot
- CNRS 7291, Laboratoire de Neurosciences Cognitives, Aix Marseille University, Marseille, France
| | - Marie-Christine Tonon
- INSERM U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, Rouen, France
| | - Vincent Prévot
- University of Lille, INSERM, CHU Lille, Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience and Cognition, UMR-S 1172, European Genomic Institute of Diabetes (EGID), Lille, France
| | - Jérôme Leprince
- INSERM U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, Rouen, France
| | - Jean-Denis Troadec
- CNRS 7291, Laboratoire de Neurosciences Cognitives, Aix Marseille University, Marseille, France
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15
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Dunigan AI, Swanson AM, Olson DP, Roseberry AG. Whole-brain efferent and afferent connectivity of mouse ventral tegmental area melanocortin-3 receptor neurons. J Comp Neurol 2020; 529:1157-1183. [PMID: 32856297 DOI: 10.1002/cne.25013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 07/10/2020] [Accepted: 08/14/2020] [Indexed: 12/27/2022]
Abstract
The mesolimbic dopamine (DA) system is involved in the regulation of multiple behaviors, including feeding, and evidence demonstrates that the melanocortin system can act on the mesolimbic DA system to control feeding and other behaviors. The melanocortin-3 receptor (MC3R) is an important component of the melanocortin system, but its overall role is poorly understood. Because MC3Rs are highly expressed in the ventral tegmental area (VTA) and are likely to be the key interaction point between the melanocortin and mesolimbic DA systems, we set out to identify both the efferent projection patterns of VTA MC3R neurons and the location of the neurons providing afferent input to them. VTA MC3R neurons were broadly connected to neurons across the brain but were strongly connected to a discrete set of brain regions involved in the regulation of feeding, reward, and aversion. Surprisingly, experiments using monosynaptic rabies virus showed that proopiomelanocortin (POMC) and agouti-related protein (AgRP) neurons in the arcuate nucleus made few direct synapses onto VTA MC3R neurons or any of the other major neuronal subtypes in the VTA, despite being extensively labeled by general retrograde tracers injected into the VTA. These results greatly contribute to our understanding of the anatomical interactions between the melanocortin and mesolimbic systems and provide a foundation for future studies of VTA MC3R neurons and the circuits containing them in the control of feeding and other behaviors.
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Affiliation(s)
- Anna I Dunigan
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Andrew M Swanson
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - David P Olson
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
| | - Aaron G Roseberry
- Department of Biology, Georgia State University, Atlanta, Georgia, USA.,Neuroscience Institute, Georgia State University, Atlanta, Georgia, USA
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16
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Florea A, El Hof FA, Hazi GM, Oprea MC. Bee Venom Stimulates Hormone Secretion in Rat Somatotroph and Corticotroph Cells: Digital Image Analysis of Secretory Granules. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2019; 25:1234-1245. [PMID: 31526405 DOI: 10.1017/s1431927619014910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study, we characterized secretory granules in somatotroph (STCs) and corticotroph (CTCs) cells from the anterior pituitary of rats, in conjunction with different experimental treatments with bee venom (BV). In the rats injected for 30 days with daily BV doses equivalent to one sting, we found significant changes in secretory granules' diameter: reduced by 48.15% in STCs and increased by 5.09% in CTCs, and especially a shift to gray into their intensity profile: increased by 237.04% in STCs and by 212.38% in CTCs. In the rats injected with a single high BV dose, the granules' diameter was reduced in both STCs (by 7.14%) and CTCs (by 4.67%-significant) and their gray intensity profile increased by 200% in STCs and by 51.71% in CTCs (both are significant). The changes in the gray profile reflected a reduced content of granules in the cells, consistent with an increase of the plasma levels of GH and ACTH in all cases. We concluded that the reduced hormone cargo of granules in STCs and CTCs resulted from an accelerated cell secretion. The results obtained for the two types of cells correlated, indicating a similar reaction of these secretory cells to the prolonged and acute presence of BV in the organism.
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Affiliation(s)
- Adrian Florea
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, 6 Louis Pasteur Street, 400349 Cluj-Napoca, Romania
| | - Fares Abu El Hof
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, 6 Louis Pasteur Street, 400349 Cluj-Napoca, Romania
| | - Georgeta Maria Hazi
- Endocrinology Clinic Laboratory, Cluj-Napoca County Emergency Hospital, 3-5 Louis Pasteur Street, 400369 Cluj-Napoca, Romania
| | - Marius Cristian Oprea
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, 6 Louis Pasteur Street, 400349 Cluj-Napoca, Romania
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17
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Derkach K, Zakharova I, Zorina I, Bakhtyukov A, Romanova I, Bayunova L, Shpakov A. The evidence of metabolic-improving effect of metformin in Ay/a mice with genetically-induced melanocortin obesity and the contribution of hypothalamic mechanisms to this effect. PLoS One 2019; 14:e0213779. [PMID: 30870482 PMCID: PMC6417728 DOI: 10.1371/journal.pone.0213779] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 02/19/2019] [Indexed: 12/16/2022] Open
Abstract
In diet-induced obesity, metformin (MF) has weight-lowering effect and improves glucose homeostasis and insulin sensitivity. However, there is no information on the efficiency of MF and the mechanisms of its action in melanocortin-type obesity. We studied the effect of the 10-day treatment with MF at the doses of 200, 400 and 600 mg/kg/day on the food intake and the metabolic and hormonal parameters in female C57Bl/6J (genotype Ay/a) agouti-mice with melanocortin-type obesity, and the influence of MF on the hypothalamic signaling in obese animals at the most effective metabolic dose (600 mg/kg/day). MF treatment led to a decrease in food intake, the body and fat weights, the plasma levels of glucose, insulin and leptin, all increased in agouti-mice, to an improvement of the lipid profile and glucose sensitivity, and to a reduced fatty liver degeneration. In the hypothalamus of obese agouti-mice, the leptin and insulin content was reduced and the expression of the genes encoding leptin receptor (LepR), MC3- and MC4-melanocortin receptors and pro-opiomelanocortin (POMC), the precursor of anorexigenic melanocortin peptides, was increased. The activities of AMP-activated kinase (AMPK) and the transcriptional factor STAT3 were increased, while Akt-kinase activity did not change from control C57Bl/6J (a/a) mice. In the hypothalamus of MF-treated agouti-mice (10 days, 600 mg/kg/day), the leptin and insulin content was restored, Akt-kinase activity was increased, and the activities of AMPK and STAT3 were reduced and did not differ from control mice. In the hypothalamus of MF-treated agouti-mice, the Pomc gene expression was six times higher than in control, while the gene expression for orexigenic neuropeptide Y was decreased by 39%. Thus, we first showed that MF treatment leads to an improvement of metabolic parameters and a decrease of hyperleptinemia and hyperinsulinaemia in genetically-induced melanocortin obesity, and the specific changes in the hypothalamic signaling makes a significant contribution to this effect of MF.
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Affiliation(s)
- Kira Derkach
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Irina Zakharova
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Inna Zorina
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Andrey Bakhtyukov
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Irina Romanova
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Liubov Bayunova
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Alexander Shpakov
- Department of Molecular Endocrinology and Neurochemistry, Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
- * E-mail:
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18
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Yong J, Tian J, Dang H, Wu TT, Atkinson MA, Sun R, Kaufman DL. Increased risk for T cell autoreactivity to ß-cell antigens in the mice expressing the A vy obesity-associated gene. Sci Rep 2019; 9:4269. [PMID: 30862859 PMCID: PMC6414670 DOI: 10.1038/s41598-019-38905-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 01/14/2019] [Indexed: 12/17/2022] Open
Abstract
There has been considerable debate as to whether obesity can act as an accelerator of type 1 diabetes (T1D). We assessed this possibility using transgenic mice (MIP-TF mice) whose ß-cells express enhanced green fluorescent protein (EGFP). Infecting these mice with EGFP-expressing murine herpes virus-68 (MHV68-EGFP) caused occasional transient elevation in their blood glucose, peri-insulitis, and Th1 responses to EGFP which did not spread to other ß-cell antigens. We hypothesized that obesity-related systemic inflammation and ß-cell stress could exacerbate the MHV68-EGFP-induced ß-cell autoreactivity. We crossed MIP-TF mice with Avy mice which develop obesity and provide models of metabolic disease alongside early stage T2D. Unlike their MIP-TF littermates, MHV68-EGFP-infected Avy/MIP-TF mice developed moderate intra-insulitis and transient hyperglycemia. MHV68-EGFP infection induced a more pronounced intra-insulitis in older, more obese, Avy/MIP-TF mice. Moreover, in MHV68-EGFP-infected Avy/MIP-TF mice, Th1 reactivity spread from EGFP to other ß-cell antigens. Thus, the spreading of autoreactivity among ß-cell antigens corresponded with the transition from peri-insulitis to intra-insulitis and occurred in obese Avy/MIP-TF mice but not lean MIP-TF mice. These observations are consistent with the notion that obesity-associated systemic inflammation and ß-cell stress lowers the threshold necessary for T cell autoreactivity to spread from EGFP to other ß-cell autoantigens.
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Affiliation(s)
- Jing Yong
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095-1735, United States.,Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, 92037, United States
| | - Jide Tian
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095-1735, United States
| | - Hoa Dang
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095-1735, United States
| | - Ting-Ting Wu
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095-1735, United States
| | - Mark A Atkinson
- Departments of Pathology and Paediatrics, University of Florida Diabetes Institute, Gainesville, FL, 32610, United States
| | - Ren Sun
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095-1735, United States
| | - Daniel L Kaufman
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095-1735, United States.
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19
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Eerola K, Virtanen S, Vähätalo L, Ailanen L, Cai M, Hruby V, Savontaus M, Savontaus E. Hypothalamic γ-melanocyte stimulating hormone gene delivery reduces fat mass in male mice. J Endocrinol 2018; 239:19–31. [PMID: 30307151 DOI: 10.1530/joe-18-0009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
γ-Melanocyte stimulating hormone (γ-MSH) is an endogenous agonist of the melanocortin 3-receptor (MC3R). Genetic disruption of MC3Rs increases adiposity and blunts responses to fasting, suggesting that increased MC3R signaling could be physiologically beneficial in the long term. Interestingly, several studies have concluded that activation of MC3Rs is orexigenic in the short term. Therefore, we aimed to examine the short- and long-term effects of γ-MSH in the hypothalamic arcuate nucleus (ARC) on energy homeostasis and hypothesized that the effect of MC3R agonism is dependent on the state of energy balance and nutrition. Lentiviral gene delivery was used to induce a continuous expression of γ-Msh only in the ARC of male C57Bl/6N mice. Parameters of body energy homeostasis were monitored as food was changed from chow (6 weeks) to Western diet (13 weeks) and back to chow (7 weeks). The γ-MSH treatment decreased the fat mass to lean mass ratio on chow, but the effect was attenuated on Western diet. After the switch back to chow, an enhanced loss in weight (−15% vs −6%) and fat mass (−37% vs −12%) and reduced cumulative food intake were observed in γ-MSH-treated animals. Fasting-induced feeding was increased on chow diet only; however, voluntary running wheel activity on Western diet was increased. The γ-MSH treatment also modulated the expression of key neuropeptides in the ARC favoring weight loss. We have shown that a chronic treatment intended to target ARC MC3Rs modulates energy balance in nutritional state-dependent manner. Enhancement of diet-induced weight loss could be beneficial in treatment of obesity.
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Affiliation(s)
- K Eerola
- Institute of Biomedicine, Research Center for Integrative Physiology and Pharmacology and Turku Center for Disease Modeling, University of Turku, Turku, Finland
- Turku Centre for Biotechnology, University of Turku, Turku, Finland
| | - S Virtanen
- Institute of Biomedicine, Research Center for Integrative Physiology and Pharmacology and Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - L Vähätalo
- Institute of Biomedicine, Research Center for Integrative Physiology and Pharmacology and Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - L Ailanen
- Institute of Biomedicine, Research Center for Integrative Physiology and Pharmacology and Turku Center for Disease Modeling, University of Turku, Turku, Finland
- Drug Research Doctoral Program, University of Turku, Turku, Finland
| | - M Cai
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, USA
| | - V Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, USA
| | - M Savontaus
- Turku Centre for Biotechnology, University of Turku, Turku, Finland
- Heart Center, Turku University Hospital and University of Turku, Turku, Finland
| | - E Savontaus
- Institute of Biomedicine, Research Center for Integrative Physiology and Pharmacology and Turku Center for Disease Modeling, University of Turku, Turku, Finland
- Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
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20
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Integrating Thyroid Hormone Signaling in Hypothalamic Control of Metabolism: Crosstalk Between Nuclear Receptors. Int J Mol Sci 2018; 19:ijms19072017. [PMID: 29997323 PMCID: PMC6073315 DOI: 10.3390/ijms19072017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/06/2018] [Accepted: 07/06/2018] [Indexed: 12/18/2022] Open
Abstract
The obesity epidemic is well recognized as a significant global health issue. A better understanding of the energy homeostasis mechanisms could help to identify promising anti-obesity therapeutic strategies. It is well established that the hypothalamus plays a pivotal role governing energy balance. The hypothalamus consists of tightly interconnected and specialized neurons that permit the sensing and integration of several peripheral inputs, including metabolic and hormonal signals for an appropriate physiological response. Current evidence shows that thyroid hormones (THs) constitute one of the key endocrine factors governing the regulation and the integration of metabolic homeostasis at the hypothalamic level. THs modulate numerous genes involved in the central control of metabolism, as TRH (Thyrotropin-Releasing Hormone) and MC4R (Melanocortin 4 Receptor). THs act through their interaction with thyroid hormone receptors (TRs). Interestingly, TH signaling, especially regarding metabolic regulations, involves TRs crosstalk with other metabolically linked nuclear receptors (NRs) including PPAR (Peroxisome proliferator-activated receptor) and LXR (Liver X receptor). In this review, we will summarize current knowledge on the important role of THs integration of metabolic pathways in the central regulation of metabolism. Particularly, we will shed light on the crosstalk between TRs and other NRs in controlling energy homeostasis. This could be an important track for the development of attractive therapeutic compounds.
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21
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Dezfuli G, Gillis RA, Tatge JE, Duncan KR, Dretchen KL, Jackson PG, Verbalis JG, Sahibzada N. Subdiaphragmatic Vagotomy With Pyloroplasty Ameliorates the Obesity Caused by Genetic Deletion of the Melanocortin 4 Receptor in the Mouse. Front Neurosci 2018; 12:104. [PMID: 29545738 PMCID: PMC5838008 DOI: 10.3389/fnins.2018.00104] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 02/12/2018] [Indexed: 12/22/2022] Open
Abstract
Background/Objectives: We tested the hypothesis that abolishing vagal nerve activity will reverse the obesity phenotype of melanocortin 4 receptor knockout mice (Mc4r−/−). Subjects/Methods: In two separate studies, we examined the efficacy of bilateral subdiaphragmatic vagotomy (SDV) with pyloroplasty in the prevention and treatment of obesity in Mc4r−/− mice. Results: In the first study, SDV prevented >20% increase in body weight (BW) associated with this genotype. This was correlated with a transient reduction in overall food intake (FI) in the preventative arm of the study. Initially, SDV mice had reduced weekly FI; however, FI normalized to that of controls and baseline FI within the 8-week study period. In the second study, the severe obesity that is characteristic of the adult Mc4r−/− genotype was significantly improved by SDV with a magnitude of 30% loss in excess BW over a 4-week period. Consistent with the first preventative study, within the treatment arm, SDV mice also demonstrated a transient reduction in FI relative to control and baseline levels that normalized over subsequent weeks. In addition to the accompanying loss in weight, mice subjected to SDV showed a decrease in respiratory exchange ratio (RER), and an increase in locomotor activity (LA). Analysis of the white fat-pad deposits of these mice showed that they were significantly less than the control groups. Conclusions: Altogether, our data demonstrates that SDV both prevents gain in BW and causes weight loss in severely obese Mc4r−/− mice. Moreover, it suggests that an important aspect of weight reduction for this type of monogenic obesity involves loss of signaling in vagal motor neurons.
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Affiliation(s)
- Ghazaul Dezfuli
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC, United States
| | - Richard A Gillis
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC, United States
| | - Jaclyn E Tatge
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC, United States
| | - Kimbell R Duncan
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC, United States
| | - Kenneth L Dretchen
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC, United States
| | - Patrick G Jackson
- Department of Surgery, Georgetown University Medical Center, Washington, DC, United States
| | - Joseph G Verbalis
- Department of Medicine, Georgetown University Medical Center, Washington, DC, United States
| | - Niaz Sahibzada
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC, United States
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22
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Yu CH, Hsieh YS, Chen PN, Chen JR, Kuo DY. Knockdown of the transcript of ERK in the brain modulates hypothalamic neuropeptide-mediated appetite control in amphetamine-treated rats. Br J Pharmacol 2018; 175:726-739. [PMID: 29215157 DOI: 10.1111/bph.14120] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 11/03/2017] [Accepted: 11/17/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE Amphetamine is a releaser of dopamine stored in synaptic terminals, which can suppress appetite by changing the expression levels of neuropeptide Y (NPY) and proopiomelanocortin (POMC) in the hypothalamus. This study explored whether ERKs are involved in appetite control mediated by cAMP response element binding protein (CREB), NPY and POMC in amphetamine-treated rats. EXPERIMENTAL APPROACH Rats were given amphetamine for 4 days, and changes in feeding behaviour and expression levels of phosphorylated-ERK (pERK), pCREB, NPY and melanocortin MC3 receptors were examined and compared. KEY RESULTS Following amphetamine treatment, food intake, body weight and NPY expression decreased, whereas the expression of pERK, pCREB, MC3 receptors and pCREB/DNA binding activity increased. In amphetamine-treated rats, both cerebral ERK knockdown and pretreatment with a peripheral dopamine receptor antagonist decreased NPY but increased pERK, pCREB and MC3 receptor expression. Moreover, the immunofluorescence of hypothalamic pERK increased following amphetamine treatment. CONCLUSIONS AND IMPLICATIONS These results suggest that ERK/CREB signalling participates in the effects mediated by dopamine receptor/NPY/POMC on appetite control in rats treated with amphetamine. These findings advance the knowledge on the involvement of ERK/CREB signalling in the reciprocal regulation by NPY and POMC of appetite after amphetamine treatment.
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Affiliation(s)
- Ching-Han Yu
- Department of Physiology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City, Taiwan
| | - Yih-Shou Hsieh
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City, Taiwan
| | - Pei-Ni Chen
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City, Taiwan
| | - Jeng-Rung Chen
- Department of Veterinary Medicine, National Chung Hsing University, Taichung City, Taiwan, R.O.C
| | - Dong-Yih Kuo
- Department of Physiology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City, Taiwan
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23
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Mountjoy KG, Caron A, Hubbard K, Shome A, Grey AC, Sun B, Bould S, Middleditch M, Pontré B, McGregor A, Harris PWR, Kowalczyk R, Brimble MA, Botha R, Tan KML, Piper SJ, Buchanan C, Lee S, Coll AP, Elmquist JK. Desacetyl-α-melanocyte stimulating hormone and α-melanocyte stimulating hormone are required to regulate energy balance. Mol Metab 2017; 9:207-216. [PMID: 29226825 PMCID: PMC5869732 DOI: 10.1016/j.molmet.2017.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/08/2017] [Accepted: 11/14/2017] [Indexed: 01/15/2023] Open
Abstract
Objective Regulation of energy balance depends on pro-opiomelanocortin (POMC)-derived peptides and melanocortin-4 receptor (MC4R). Alpha-melanocyte stimulating hormone (α-MSH) is the predicted natural POMC-derived peptide that regulates energy balance. Desacetyl-α-MSH, the precursor for α-MSH, is present in brain and blood. Desacetyl-α-MSH is considered to be unimportant for regulating energy balance despite being more potent (compared with α-MSH) at activating the appetite-regulating MC4R in vitro. Thus, the physiological role for desacetyl-α-MSH is still unclear. Methods We created a novel mouse model to determine whether desacetyl-α-MSH plays a role in regulating energy balance. We engineered a knock in targeted QKQR mutation in the POMC protein cleavage site that blocks the production of both desacetyl-α-MSH and α-MSH from adrenocorticotropin (ACTH1-39). Results The mutant ACTH1-39 (ACTHQKQR) functions similar to native ACTH1-39 (ACTHKKRR) at the melanocortin 2 receptor (MC2R) in vivo and MC4R in vitro. Male and female homozygous mutant ACTH1-39 (Pomctm1/tm1) mice develop the characteristic melanocortin obesity phenotype. Replacement of either desacetyl-α-MSH or α-MSH over 14 days into Pomctm1/tm1 mouse brain significantly reverses excess body weight and fat mass gained compared to wild type (WT) (Pomcwt/wt) mice. Here, we identify both desacetyl-α-MSH and α-MSH peptides as regulators of energy balance and highlight a previously unappreciated physiological role for desacetyl-α-MSH. Conclusions Based on these data we propose that there is potential to exploit the naturally occurring POMC-derived peptides to treat obesity but this relies on first understanding the specific function(s) for desacetyl-α-MSH and α-MSH. KKRR → QKQR mutation in the cleavage site of POMC prevents the production of desacetyl-α-MSH and α-MSH in mice. Male and female mutant mice develop characteristic melanocortin obesity. Central administration of α-MSH is more potent at reducing body weight in female mutant mice. Central administration of desacetyl-α-MSH and α-MSH are similarly potent at reducing body weight in male mutant mice.
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Affiliation(s)
- Kathleen G Mountjoy
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| | - Alexandre Caron
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kristina Hubbard
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Avik Shome
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Angus C Grey
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Department of Anatomy and Medical Imaging, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Bo Sun
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Sarah Bould
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Martin Middleditch
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Beau Pontré
- Department of Anatomy and Medical Imaging, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Ailsa McGregor
- Department of Pharmacy, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Paul W R Harris
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Renata Kowalczyk
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Margaret A Brimble
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Rikus Botha
- Department of Physiology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Karen M L Tan
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 2QR, United Kingdom
| | - Sarah J Piper
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 2QR, United Kingdom
| | - Christina Buchanan
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Syann Lee
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Anthony P Coll
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 2QR, United Kingdom; University of Cambridge Metabolic Research Laboratories, MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Joel K Elmquist
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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24
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Xiao Y, Xia T, Yu J, Deng Y, Liu H, Liu B, Chen S, Liu Y, Guo F. Knockout of inositol-requiring enzyme 1α in pro-opiomelanocortin neurons decreases fat mass via increasing energy expenditure. Open Biol 2017; 6:rsob.160131. [PMID: 27558934 PMCID: PMC5008012 DOI: 10.1098/rsob.160131] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 07/15/2016] [Indexed: 01/21/2023] Open
Abstract
Although numerous functions of inositol-requiring enzyme 1α (IRE1α) have been identified, a role of IRE1α in pro-opiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus is largely unknown. Here, we showed that mice lacking IRE1α specifically in POMC neurons (PIKO) are lean and resistant to high-fat diet-induced obesity and obesity-related insulin resistance, liver steatosis and leptin resistance. Furthermore, PIKO mice had higher energy expenditure, probably due to increased thermogenesis in brown adipose tissue. Additionally, α-melanocyte-stimulating hormone production was increased in the hypothalamus of PIKO mice. These results demonstrate that IRE1α in POMC neurons plays a critical role in the regulation of obesity and obesity-related metabolic disorders. Our results also suggest that IRE1α is not only an endoplasmic reticulum stress sensor, but also a new potential therapeutic target for obesity and obesity-related metabolic diseases.
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Affiliation(s)
- Yuzhong Xiao
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Tingting Xia
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Junjie Yu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Yalan Deng
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Hao Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Bin Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Shanghai Chen
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Yong Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
| | - Feifan Guo
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, The Graduate School of the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, People's Republic of China
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25
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Lanfray D, Richard D. Emerging Signaling Pathway in Arcuate Feeding-Related Neurons: Role of the Acbd7. Front Neurosci 2017; 11:328. [PMID: 28690493 PMCID: PMC5481368 DOI: 10.3389/fnins.2017.00328] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 05/24/2017] [Indexed: 01/28/2023] Open
Abstract
The understanding of the mechanisms whereby energy balance is regulated is essential to the unraveling of the pathophysiology of obesity. In the last three decades, focus was put on the metabolic role played by the hypothalamic neurons expressing proopiomelanocortin (POMC) and cocaine and amphetamine regulated transcript (CART) and the neurons co-localizing agouti-related peptide (AgRP), neuropeptide Y (NPY), and gamma-aminobutyric acid (GABA). These neurons are part of the leptin-melanocortin pathway, whose role is key in energy balance regulation. More recently, the metabolic involvement of further hypothalamic uncharacterized neuron populations has been suggested. In this review, we discuss the potential homeostatic implication of hypothalamic GABAergic neurons that produce Acyl-Coa-binding domain containing protein 7 (ACBD7), precursor of the nonadecaneuropeptide (NDN), which has recently been characterized as a potent anorexigenic neuropeptide capable of relaying the leptin anorectic/thermogenic effect via the melanocortin system.
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Affiliation(s)
- Damien Lanfray
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université LavalQuébec, QC, Canada
| | - Denis Richard
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université LavalQuébec, QC, Canada
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26
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Effect of Xiaoyao San on the brain-gut axis in rats after chronic immobilization stress. JOURNAL OF TRADITIONAL CHINESE MEDICAL SCIENCES 2017. [DOI: 10.1016/j.jtcms.2017.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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27
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Butler AA, Girardet C, Mavrikaki M, Trevaskis JL, Macarthur H, Marks DL, Farr SA. A Life without Hunger: The Ups (and Downs) to Modulating Melanocortin-3 Receptor Signaling. Front Neurosci 2017; 11:128. [PMID: 28360832 PMCID: PMC5352694 DOI: 10.3389/fnins.2017.00128] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/01/2017] [Indexed: 11/13/2022] Open
Abstract
Melanocortin neurons conserve body mass in hyper- or hypo-caloric conditions by conveying signals from nutrient sensors into areas of the brain governing appetite and metabolism. In mice, melanocortin-3 receptor (MC3R) deletion alters nutrient partitioning independently of hyperphagia, promoting accumulation of fat over muscle mass. Enhanced rhythms in insulin and insulin-responsive metabolic genes during hypocaloric feeding suggest partial insulin resistance and enhanced lipogenesis. However, exactly where and how MC3Rs affect metabolic control to alter nutrient partitioning is not known. The behavioral phenotypes exhibited by MC3R-deficient mice suggest a contextual role in appetite control. The impact of MC3R-deficiency on feeding behavior when food is freely available is minor. However, homeostatic responses to hypocaloric conditioning involving increased expression of appetite-stimulating (orexigenic) neuropeptides, binge-feeding, food anticipatory activity (FAA), entrainment to nutrient availability and enhanced feeding-related motivational responses are compromised with MC3R-deficiency. Rescuing Mc3r transcription in hypothalamic and limbic neurons improves appetitive responses during hypocaloric conditioning while having minor effects on nutrient partitioning, suggesting orexigenic functions. Rescuing hypothalamic MC3Rs also restores responses of fasting-responsive hypothalamic orexigenic neurons in hypocaloric conditions, suggesting actions that sensitize fasting-responsive neurons to signals from nutrient sensors. MC3R signaling in ventromedial hypothalamic SF1(+ve) neurons improves metabolic control, but does not restore appetitive responses or nutrient partitioning. In summary, desensitization of fasting-responsive orexigenic neurons may underlie attenuated appetitive responses of MC3R-deficient mice in hypocaloric situations. Further studies are needed to identify the specific location(s) of MC3Rs controlling appetitive responses and partitioning of nutrients between fat and lean tissues.
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Affiliation(s)
- Andrew A Butler
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine St. Louis, MO, USA
| | - Clemence Girardet
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine St. Louis, MO, USA
| | - Maria Mavrikaki
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine St. Louis, MO, USA
| | - James L Trevaskis
- In vivo Pharmacology, Cardiovascular and Metabolic Disease, Medimmune Gaithersburg, MD, USA
| | - Heather Macarthur
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine St. Louis, MO, USA
| | - Daniel L Marks
- Papé Family Pediatric Research Institute, Oregon Health and Science University Portland, OR, USA
| | - Susan A Farr
- Department of Internal Medicine, Division of Geriatrics, Saint Louis University School of MedicineSt. Louis, MO, USA; VA Medical CenterSt. Louis, MO, USA
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28
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Melanocortin-3 receptors expressed in Nkx2.1(+ve) neurons are sufficient for controlling appetitive responses to hypocaloric conditioning. Sci Rep 2017; 7:44444. [PMID: 28294152 PMCID: PMC5353610 DOI: 10.1038/srep44444] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 02/08/2017] [Indexed: 01/12/2023] Open
Abstract
Melanocortin-3 receptors (MC3R) have a contextual role in appetite control that is amplified with hypocaloric conditioning. C57BL/6J (B6) mice subjected to hypocaloric feeding schedules (HFS) exhibit compulsive behavioral responses involving food anticipatory activity (FAA) and caloric loading following food access. These homeostatic responses to calorie-poor environs are attenuated in B6 mice in which Mc3r transcription is suppressed by a lox-stop-lox sequence in the 5'UTR (Mc3rTB/TB). Here, we report that optimization of caloric loading in B6 mice subject to HFS, characterized by increased meal size and duration, is not observed in Mc3rTB/TB mice. Analysis of hypothalamic and neuroendocrine responses to HFS throughout the light-dark cycle suggests uncoupling of hypothalamic responses involving appetite-stimulating fasting-responsive hypothalamic neurons expressing agouti-related peptide (AgRP) and neuropeptide Y (Npy). Rescuing Mc3rs expression in Nkx2.1(+ve) neurons is sufficient to restore normal hypothalamic responses to negative energy balance. In addition, Mc3rs expressed in Nkx2.1(+ve) neurons are also sufficient to restore FAA and caloric loading of B6 mice subjected to HFS. In summary, MC3Rs expressed in Nkx2.1(+ve) neurons are sufficient to coordinate hypothalamic response and expression of compulsive behavioral responses involving meal anticipation and consumption of large meals during situations of prolonged negative energy balance.
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29
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Caron A, Richard D. Neuronal systems and circuits involved in the control of food intake and adaptive thermogenesis. Ann N Y Acad Sci 2016; 1391:35-53. [PMID: 27768821 DOI: 10.1111/nyas.13263] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 08/18/2016] [Accepted: 08/24/2016] [Indexed: 12/27/2022]
Abstract
With the still-growing prevalence of obesity worldwide, major efforts are made to understand the various behavioral, environmental, and genetic factors that promote excess fat gain. Obesity results from an imbalance between energy intake and energy expenditure, which emphasizes the importance of deciphering the mechanisms behind energy balance regulation to understand its physiopathology. The control of energy balance is assured by brain systems/circuits capable of generating adequate ingestive and thermogenic responses to maintain the stability of energy reserves, which implies a proper integration of the homeostatic signals that inform about the status of the energy stores. In this article, we overview the organization and functionality of key neuronal circuits or pathways involved in the control of food intake and energy expenditure. We review the role of the corticolimbic (executive and reward) and autonomic systems that integrate their activities to regulate energy balance. We also describe the mechanisms and pathways whereby homeostatic sensing is achieved in response to variations of homeostatic hormones, such as leptin, insulin, and ghrelin, while putting some emphasis on the prominent importance of the mechanistic target of the rapamycin signaling pathway in coordinating the homeostatic sensing process.
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Affiliation(s)
- Alexandre Caron
- Institut Universitaire de Cardiologie et de Pneumologie de Quebec and Faculty of Medicine, Department of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Denis Richard
- Institut Universitaire de Cardiologie et de Pneumologie de Quebec and Faculty of Medicine, Department of Medicine, Université Laval, Quebec City, Quebec, Canada
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30
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Gavini CK, Jones WC, Novak CM. Ventromedial hypothalamic melanocortin receptor activation: regulation of activity energy expenditure and skeletal muscle thermogenesis. J Physiol 2016; 594:5285-301. [PMID: 27126579 PMCID: PMC5023712 DOI: 10.1113/jp272352] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 04/25/2016] [Indexed: 01/13/2023] Open
Abstract
KEY POINTS The ventromedial hypothalamus (VMH) and the central melanocortin system both play vital roles in regulating energy balance by modulating energy intake and utilization. Recent evidence suggests that activation of the VMH alters skeletal muscle metabolism. We show that intra-VMH melanocortin receptor activation increases energy expenditure and physical activity, switches fuel utilization to fats, and lowers work efficiency such that excess calories are dissipated by skeletal muscle as heat. We also show that intra-VMH melanocortin receptor activation increases sympathetic nervous system outflow to skeletal muscle. Intra-VMH melanocortin receptor activation also induced significant changes in the expression of mediators of energy expenditure in muscle. These results support the role of melanocortin receptors in the VMH in the modulation of skeletal muscle metabolism. ABSTRACT The ventromedial hypothalamus (VMH) and the brain melanocortin system both play vital roles in increasing energy expenditure (EE) and physical activity, decreasing appetite and modulating sympathetic nervous system (SNS) outflow. Because of recent evidence showing that VMH activation modulates skeletal muscle metabolism, we propose the existence of an axis between the VMH and skeletal muscle, modulated by brain melanocortins, modelled on the brain control of brown adipose tissue. Activation of melanocortin receptors in the VMH of rats using a non-specific agonist melanotan II (MTII), compared to vehicle, increased oxygen consumption and EE and decreased the respiratory exchange ratio. Intra-VMH MTII enhanced activity-related EE even when activity levels were held constant. MTII treatment increased gastrocnemius muscle heat dissipation during controlled activity, as well as in the home cage. Compared to vehicle-treated rats, rats with intra-VMH melanocortin receptor activation had higher skeletal muscle norepinephrine turnover, indicating an increased SNS drive to muscle. Lastly, intra-VMH MTII induced mRNA expression of muscle energetic mediators, whereas short-term changes at the protein level were primarily limited to phosphorylation events. These results support the hypothesis that melanocortin peptides act in the VMH to increase EE by lowering the economy of activity via the enhanced expression of mediators of EE in the periphery including skeletal muscle. The data are consistent with the role of melanocortins in the VMH in the modulation of skeletal muscle metabolism.
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MESH Headings
- Adipose Tissue, Brown/drug effects
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, Brown/physiology
- Adipose Tissue, White/drug effects
- Adipose Tissue, White/metabolism
- Adipose Tissue, White/physiology
- Animals
- Energy Metabolism
- Hypothalamus/physiology
- Liver/drug effects
- Liver/metabolism
- Liver/physiology
- Male
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/physiology
- Norepinephrine/metabolism
- Peptides, Cyclic/pharmacology
- Physical Conditioning, Animal
- Rats, Sprague-Dawley
- Receptors, Melanocortin/agonists
- Receptors, Melanocortin/physiology
- Thermogenesis
- alpha-MSH/analogs & derivatives
- alpha-MSH/pharmacology
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Affiliation(s)
- Chaitanya K Gavini
- School of Biomedical Sciences, Kent State University, Kent, OH, USA.
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA.
| | - William C Jones
- Department of Exercise Science/Physiology, College of Education, Health, and Human Services, Kent State University, Kent, OH, USA
| | - Colleen M Novak
- School of Biomedical Sciences, Kent State University, Kent, OH, USA
- Department of Biological Sciences, Kent State University, Kent, OH, USA
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31
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Gao M, Cheng K, Yin H. Targeting protein-protein interfaces using macrocyclic peptides. Biopolymers 2016; 104:310-6. [PMID: 25664609 DOI: 10.1002/bip.22625] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 01/29/2015] [Accepted: 02/01/2015] [Indexed: 01/10/2023]
Abstract
Protein-protein interactions (PPIs) are critical in numerous biological processes including signaling transduction, function regulations, and disease development. To regulate PPIs has been thought to be challenging due to their highly dynamic and expansive interfacial areas. Nonetheless, successful examples have been reported of targeting PPIs using small molecules, peptides, and proteins. Peptides, especially macrocyclic peptides have proven to be a particularly useful tool to inhibit PPIs for their exquisite potency, stability and selectivity. Herein we review the recent developments of this area of research, focusing on the macrocyclic peptides isolated from natural products, identified from library screening, and rationally designed based on structures, as PPI regulators.
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Affiliation(s)
- Meng Gao
- Department of Chemistry, Center of Basic Molecular Science, Tsinghua University, Beijing, China , 100082
| | - Kui Cheng
- Department of Chemistry, Center of Basic Molecular Science, Tsinghua University, Beijing, China , 100082
| | - Hang Yin
- Department of Chemistry, Center of Basic Molecular Science, Tsinghua University, Beijing, China , 100082.,Department of Chemistry and Biochemistry, the BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, 80309-0596
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32
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Mavrikaki M, Girardet C, Kern A, Faruzzi Brantley A, Miller CA, Macarthur H, Marks DL, Butler AA. Melanocortin-3 receptors in the limbic system mediate feeding-related motivational responses during weight loss. Mol Metab 2016; 5:566-579. [PMID: 27408780 PMCID: PMC4921936 DOI: 10.1016/j.molmet.2016.05.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 04/28/2016] [Accepted: 05/04/2016] [Indexed: 12/21/2022] Open
Abstract
Objective Appetitive responses to weight loss are mediated by a nutrient-sensing neural network comprised of melanocortin neurons. The role of neural melanocortin-3 receptors (MC3R) in mediating these responses is enigmatic. Mc3r knockout mice exhibit a paradoxical phenotype of obesity and reduced feeding-related behaviors in situations of nutrient scarcity. Here we examined whether MC3Rs expressed in mesolimbic neurons regulate feeding-related motivational responses. Methods Interactions between Mc3r genotype, cognitive function and energy balance on food self-administration were assessed using operant conditioning with fixed- and progressive ratio (FR1/PR1) settings. Inhibition of Mc3r transcription by a loxP-flanked transcriptional blocker (TB) in C57BL/6JN mice (Mc3rTB/TB) was reversed in mesolimbic neurons using DAT-Cre (DAT-MC3R). Results Caloric restriction (CR) caused 10–15% weight loss and increased motivation to acquire food rewards during training sessions. c-Fos-expression in the nucleus accumbens was increased 1 h following food presentation. While exhibiting weight loss, total food self-administration, enhanced motivation to self-administer food rewards in training sessions held during CR and c-Fos-activation in the nucleus accumbens following re-feeding were all markedly attenuated in Mc3rTB/TB mice. In contrast, cognitive abilities were normal in Mc3rTB/TB mice. Total food self-administration during FR1 sessions was not rescued in DAT-MC3R mice, however enhanced motivational responses to self-administer food rewards in PR1 conditions were restored. The nutrient-partitioning phenotype observed with Mc3r-deficiency was not rescued in DAT-MC3R mice. Conclusions Mesolimbic MC3Rs mediate enhanced motivational responses during CR. However, they are insufficient to restore normal caloric loading when food is presented during CR and do not affect metabolic conditions altering nutrient partitioning. Food-related motivational responses in mice increase with caloric restriction (CR). Melanocortin-3 receptors (MC3R) are required for food-related motivational responses. MC3Rs role in food-related motivational responses depends on metabolic condition. Mesolimbic MC3Rs increase food-related motivational responses during CR.
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Affiliation(s)
- Maria Mavrikaki
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Pharmacology & Physiology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Clemence Girardet
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Pharmacology & Physiology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Andras Kern
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Alicia Faruzzi Brantley
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA; Behavioral Core, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Courtney A Miller
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Heather Macarthur
- Department of Pharmacology & Physiology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Daniel L Marks
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Andrew A Butler
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Pharmacology & Physiology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA.
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Caron A, Labbé SM, Mouchiroud M, Huard R, Lanfray D, Richard D, Laplante M. DEPTOR in POMC neurons affects liver metabolism but is dispensable for the regulation of energy balance. Am J Physiol Regul Integr Comp Physiol 2016; 310:R1322-31. [PMID: 27097662 DOI: 10.1152/ajpregu.00549.2015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 04/18/2016] [Indexed: 11/22/2022]
Abstract
We have recently demonstrated that specific overexpression of DEP-domain containing mTOR-interacting protein (DEPTOR) in the mediobasal hypothalamus (MBH) protects mice against high-fat diet-induced obesity, revealing DEPTOR as a significant contributor to energy balance regulation. On the basis of evidence that DEPTOR is expressed in the proopiomelanocortin (POMC) neurons of the MBH, the present study aimed to investigate whether these neurons mediate the metabolic effects of DEPTOR. Here, we report that specific DEPTOR overexpression in POMC neurons does not recapitulate any of the phenotypes observed when the protein was overexpressed in the MBH. Unlike the previous model, mice overexpressing DEPTOR only in POMC neurons 1) did not show differences in feeding behavior, 2) did not exhibit changes in locomotion activity and oxygen consumption, 3) did not show an improvement in systemic glucose metabolism, and 4) were not resistant to high-fat diet-induced obesity. These results support the idea that other neuronal populations are responsible for these phenotypes. Nonetheless, we observed a mild elevation in fasting blood glucose, insulin resistance, and alterations in liver glucose and lipid homeostasis in mice overexpressing DEPTOR in POMC neurons. Taken together, these results show that DEPTOR overexpression in POMC neurons does not affect energy balance regulation but could modulate metabolism through a brain-liver connection.
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Affiliation(s)
- Alexandre Caron
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada; and Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada.,Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Sébastien M Labbé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada; and Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada.,Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Mathilde Mouchiroud
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada; and Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada.,Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Renaud Huard
- Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Damien Lanfray
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada; and Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada.,Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Denis Richard
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada; and Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada.,Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Mathieu Laplante
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada; and Département de Médecine, Faculté de Médecine, Université Laval, Québec, Québec, Canada
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Lanfray D, Caron A, Roy MC, Laplante M, Morin F, Leprince J, Tonon MC, Richard D. Involvement of the Acyl-CoA binding domain containing 7 in the control of food intake and energy expenditure in mice. eLife 2016; 5. [PMID: 26880548 PMCID: PMC4821795 DOI: 10.7554/elife.11742] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 02/14/2016] [Indexed: 11/28/2022] Open
Abstract
Acyl-CoA binding domain-containing 7 (Acbd7) is a paralog gene of the diazepam-binding inhibitor/Acyl-CoA binding protein in which single nucleotide polymorphism has recently been associated with obesity in humans. In this report, we provide converging evidence indicating that a splice variant isoform of the Acbd7 mRNA is expressed and translated by some POMC and GABAergic-neurons in the hypothalamic arcuate nucleus (ARC). We have demonstrated that the ARC ACBD7 isoform was produced and processed into a bioactive peptide referred to as nonadecaneuropeptide (NDN) in response to catabolic signals. We have characterized NDN as a potent anorexigenic signal acting through an uncharacterized endozepine G protein-coupled receptor and subsequently via the melanocortin system. Our results suggest that ACBD7-producing neurons participate in the hypothalamic leptin signalling pathway. Taken together, these data suggest that ACBD7-producing neurons are involved in the hypothalamic control exerted on food intake and energy expenditure by the leptin-melanocortin pathway. DOI:http://dx.doi.org/10.7554/eLife.11742.001 Obesity is an increasingly common problem worldwide. To treat it effectively, we must understand how the body controls how much food a person consumes and how much energy they expend. The hypothalamus is one region of the brain that plays a critical role in regulating this energy balance. Some of the neurons in the hypothalamus can change their activity when they detect satiety hormones including the leptin, which is produced by fat cells and suppresses appetite. However, it is not clear exactly how the neurons respond to leptin and other energy-related signals. Recent studies have linked the gene that encodes a protein called ACBD7 with obesity, and showed that it is one of the genes that is overexpressed in neurons that are sensitive to leptin. Now, Lanfray et al. have discovered a population of neurons that produce a new variant of the protein in the hypothalamus of mice. When this protein variant matures, it can be cut down to form a small protein-like molecule called NDN. Further experiments showed that leptin stimulates the production of both the new ABCD7 variant and NDN. Lanfray et al. then injected mice that had been denied food for a several hours with NDN. The injected mice ate less than untreated mice, and burn more energy. NDN appears to form part of the signaling pathway through which leptin signals to the hypothalamus to control appetite. In the future, creating mice in which the activity of the gene that encodes ACBD7 can be easily disrupted could help to reveal more about how the hypothalamus helps to control energy balance. DOI:http://dx.doi.org/10.7554/eLife.11742.002
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Affiliation(s)
- Damien Lanfray
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Alexandre Caron
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Marie-Claude Roy
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Mathieu Laplante
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Fabrice Morin
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institut National de la Santé et de la Recherche Médicale, Mont-Saint-Aignan, France.,Institute for Research and Innovation in Biomedicine, Normandy University, Mont-Saint-Aignan, France
| | - Jérôme Leprince
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institut National de la Santé et de la Recherche Médicale, Mont-Saint-Aignan, France.,Institute for Research and Innovation in Biomedicine, Normandy University, Mont-Saint-Aignan, France
| | - Marie-Christine Tonon
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institut National de la Santé et de la Recherche Médicale, Mont-Saint-Aignan, France.,Institute for Research and Innovation in Biomedicine, Normandy University, Mont-Saint-Aignan, France
| | - Denis Richard
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
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A mouse model for a partially inactive obesity-associated human MC3R variant. Nat Commun 2016; 7:10522. [PMID: 26818770 PMCID: PMC4738366 DOI: 10.1038/ncomms10522] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 12/22/2015] [Indexed: 12/30/2022] Open
Abstract
We previously reported children homozygous for two MC3R sequence variants (C17A+G241A) have greater fat mass than controls. Here we show, using homozygous knock-in mouse models in which we replace murine Mc3r with wild-type human (MC3RhWT/hWT) and double-mutant (C17A+G241A) human (MC3RhDM/hDM) MC3R, that MC3RhDM/hDM have greater weight and fat mass, increased energy intake and feeding efficiency, but reduced length and fat-free mass compared with MC3RhWT/hWT. MC3RhDM/hDM mice do not have increased adipose tissue inflammatory cell infiltration or greater expression of inflammatory markers despite their greater fat mass. Serum adiponectin levels are increased in MC3RhDM/hDM mice and MC3RhDM/hDM human subjects. MC3RhDM/hDM bone- and adipose tissue-derived mesenchymal stem cells (MSCs) differentiate into adipocytes that accumulate more triglyceride than MC3RhWT/hWT MSCs. MC3RhDM/hDM impacts nutrient partitioning to generate increased adipose tissue that appears metabolically healthy. These data confirm the importance of MC3R signalling in human metabolism and suggest a previously-unrecognized role for the MC3R in adipose tissue development. The melanocortin receptor, MC3R, regulates organismal energy homeostasis. Here, Lee et al. create knock-in mice with the a mutated version of the human MC3R receptor found in obese children, and show these mice have more fat and smaller bone, yet are by and large metabolically healthy.
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Labbé SM, Caron A, Lanfray D, Monge-Rofarello B, Bartness TJ, Richard D. Hypothalamic control of brown adipose tissue thermogenesis. Front Syst Neurosci 2015; 9:150. [PMID: 26578907 PMCID: PMC4630288 DOI: 10.3389/fnsys.2015.00150] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 10/20/2015] [Indexed: 12/21/2022] Open
Abstract
It has long been known, in large part from animal studies, that the control of brown adipose tissue (BAT) thermogenesis is insured by the central nervous system (CNS), which integrates several stimuli in order to control BAT activation through the sympathetic nervous system (SNS). SNS-mediated BAT activity is governed by diverse neurons found in brain structures involved in homeostatic regulations and whose activity is modulated by various factors including oscillations of energy fluxes. The characterization of these neurons has always represented a challenging issue. The available literature suggests that the neuronal circuits controlling BAT thermogenesis are largely part of an autonomic circuitry involving the hypothalamus, brainstem and the SNS efferent neurons. In the present review, we recapitulate the latest progresses in regards to the hypothalamic regulation of BAT metabolism. We briefly addressed the role of the thermoregulatory pathway and its interactions with the energy balance systems in the control of thermogenesis. We also reviewed the involvement of the brain melanocortin and endocannabinoid systems as well as the emerging role of steroidogenic factor 1 (SF1) neurons in BAT thermogenesis. Finally, we examined the link existing between these systems and the homeostatic factors that modulate their activities.
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Affiliation(s)
- Sebastien M Labbé
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Medicine, Université Laval Québec, QC, Canada
| | - Alexandre Caron
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Medicine, Université Laval Québec, QC, Canada
| | - Damien Lanfray
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Medicine, Université Laval Québec, QC, Canada
| | - Boris Monge-Rofarello
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Medicine, Université Laval Québec, QC, Canada
| | - Timothy J Bartness
- Department of Biology, Center for Obesity Reversal (COR), Georgia State University Atlanta, GA, USA
| | - Denis Richard
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Medicine, Université Laval Québec, QC, Canada
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Shukla C, Koch LG, Britton SL, Cai M, Hruby VJ, Bednarek M, Novak CM. Contribution of regional brain melanocortin receptor subtypes to elevated activity energy expenditure in lean, active rats. Neuroscience 2015; 310:252-67. [PMID: 26404873 DOI: 10.1016/j.neuroscience.2015.09.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 12/13/2022]
Abstract
Physical activity and non-exercise activity thermogenesis (NEAT) are crucial factors accounting for individual differences in body weight, interacting with genetic predisposition. In the brain, a number of neuroendocrine intermediates regulate food intake and energy expenditure (EE); this includes the brain melanocortin (MC) system, consisting of MC peptides as well as their receptors (MCR). MC3R and MC4R have emerged as critical modulators of EE and food intake. To determine how variance in MC signaling may underlie individual differences in physical activity levels, we examined behavioral response to MC receptor agonists and antagonists in rats that show high and low levels of physical activity and NEAT, that is, high- and low-capacity runners (HCR, LCR), developed by artificial selection for differential intrinsic aerobic running capacity. Focusing on the hypothalamus, we identified brain region-specific elevations in expression of MCR 3, 4, and also MC5R, in the highly active, lean HCR relative to the less active and obesity-prone LCR. Further, the differences in activity and associated EE as a result of MCR activation or suppression using specific agonists and antagonists were similarly region-specific and directly corresponded to the differential MCR expression patterns. The agonists and antagonists investigated here did not significantly impact food intake at the doses used, suggesting that the differential pattern of receptor expression may by more meaningful to physical activity than to other aspects of energy balance regulation. Thus, MCR-mediated physical activity may be a key neural mechanism in distinguishing the lean phenotype and a target for enhancing physical activity and NEAT.
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Affiliation(s)
- C Shukla
- Department of Biological Sciences, Kent State University, Kent, OH, United States; Harvard Medical School - VA Boston Healthcare System, Boston, MA, United States.
| | - L G Koch
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - S L Britton
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - M Cai
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, United States
| | - V J Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, United States
| | - M Bednarek
- MedImmune Limited, Cambridge, United Kingdom
| | - C M Novak
- Department of Biological Sciences, Kent State University, Kent, OH, United States
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Roseberry AG, Stuhrman K, Dunigan AI. Regulation of the mesocorticolimbic and mesostriatal dopamine systems by α-melanocyte stimulating hormone and agouti-related protein. Neurosci Biobehav Rev 2015; 56:15-25. [DOI: 10.1016/j.neubiorev.2015.06.020] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 06/15/2015] [Accepted: 06/21/2015] [Indexed: 11/24/2022]
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Cai M, Marelli UK, Bao J, Beck JG, Opperer F, Rechenmacher F, McLeod KR, Zingsheim MR, Doedens L, Kessler H, Hruby VJ. Systematic Backbone Conformational Constraints on a Cyclic Melanotropin Ligand Leads to Highly Selective Ligands for Multiple Melanocortin Receptors. J Med Chem 2015. [PMID: 26218460 DOI: 10.1021/acs.jmedchem.5b00102] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Human melanocortin receptors (hMCRs) have been challenging targets to develop ligands that are explicitly selective for each of their subtypes. To modulate the conformational preferences of the melanocortin ligands and improve the biofunctional agonist/antagonist activities and selectivities, we have applied a backbone N-methylation approach on Ac-Nle-c[Asp-His-D-Nal(2')-Arg-Trp-Lys]-NH2 (Ac-Nle(4)-c[Asp(5),D-Nal(2')(7),Lys(10)]-NH2), a nonselective cyclic peptide antagonist at hMC3R and hMC4R and an agonist at hMC1R and hMC5R. Systematic N-methylated derivatives of Ac-Nle(4)-c[Asp(5),D-Nal(2')(7),Lys(10)]-NH2, with all possible backbone N-methylation combinations, have been synthesized and examined for their binding and functional activities toward melanocortin receptor subtypes 1, 3, 4, and 5 (hMCRs). Several N-methylated analogues are selective and potent agonists or antagonists for hMC1R or hMC5R or have selective antagonist activity for hMC3R. The selective hMC1R ligands show strong binding for human melanoma cells. We have also discovered the first universal antagonist (compound 19) for all subtypes of hMCRs.
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Affiliation(s)
- Minying Cai
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Udaya Kiran Marelli
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Jennifer Bao
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Johannes G Beck
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Florian Opperer
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Florian Rechenmacher
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Kaitlyn R McLeod
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Morgan R Zingsheim
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Lucas Doedens
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Horst Kessler
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany.,Department of Chemistry, Faculty of Science, King Abdulaziz University , 21589 Jeddah, Saudi Arabia
| | - Victor J Hruby
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
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Hsieh YS, Chen PN, Yu CH, Chen CH, Tsai TT, Kuo DY. Involvement of oxidative stress in the regulation of NPY/CART-mediated appetite control in amphetamine-treated rats. Neurotoxicology 2015; 48:131-41. [PMID: 25825358 DOI: 10.1016/j.neuro.2015.03.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 01/09/2023]
Abstract
Amphetamine (AMPH) treatment can suppress appetite and increase oxidative stress in the brain. AMPH-induced appetite suppression is associated with the regulation of neuropeptide Y (NPY) and cocaine- and amphetamine-regulated transcript (CART) in the hypothalamus. The present study explored whether antioxidants, including glutathione S-transferase (GST) and glutathione peroxidase (GP), were involved in this NPY/CART-mediated appetite control. Rats were treated daily with AMPH for four days. Changes in food intake and expression levels of hypothalamic NPY, CART, GST, and GP were examined and compared. Results showed that, in AMPH-treated rats, (1) food intake and NPY expression decreased, while CART, GST, and GP expression increased; (2) NPY knockdown in the brain enhanced the decrease in NPY and the increases in CART, GST, and GP expression; and (3) central inhibition of reactive oxygen species production decreased GST and GP and modulated AMPH anorexia and the expression levels of NPY and CART. The present results suggest that oxidative stress in the brain participates in regulating NPY/CART-mediated appetite control in AMPH-treated rats. These results may advance the knowledge regarding the molecular mechanism of AMPH-evoked or NPY/CART-mediated appetite suppression.
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Affiliation(s)
- Yih-Shou Hsieh
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Pei-Ni Chen
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Ching-Han Yu
- Department of Physiology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Chia-Hui Chen
- Department of Biomedical Science, College of Medical Science and Technology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Tsung-Ta Tsai
- Department of Biomedical Science, College of Medical Science and Technology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Dong-Yih Kuo
- Department of Physiology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan.
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Chu SC, Chen PN, Ho YJ, Yu CH, Hsieh YS, Kuo DY. Both neuropeptide Y knockdown and Y1 receptor inhibition modulate CART-mediated appetite control. Horm Behav 2015; 67:38-47. [PMID: 25461972 DOI: 10.1016/j.yhbeh.2014.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 11/10/2014] [Accepted: 11/13/2014] [Indexed: 01/18/2023]
Abstract
Amphetamine (AMPH)-induced appetite suppression has been attributed to its inhibition of neuropeptide Y (NPY)-containing neurons in the hypothalamus. This study examined whether hypothalamic cocaine- and amphetamine-regulated transcript (CART)-containing neurons and NPY Y1 receptor (Y1R) were involved in the action of AMPH. Rats were treated daily with AMPH for four days, and changes in feeding behavior and expression levels of NPY, CART, and POMC were assessed and compared. The results showed that both feeding behavior and NPY expression decreased during AMPH treatment, with the biggest reduction occurring on Day 2. By contrast, the expression of CART and melanocortin 3 receptor (MC3R), a member of the POMC neurotransmission, increased with the maximum response on Day 2, directly opposite to the NPY expression results. The intracerebroventricular infusion of NPY antisense or Y1R inhibitor both modulated AMPH-induced anorexia and the expression levels of MC3R and CART. The results suggest that in the hypothalamus both POMC- and CART-containing neurons participate in regulating NPY-mediated appetite control during AMPH treatment. These results may advance the knowledge of molecular mechanism of anorectic drugs.
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Affiliation(s)
- Shu-Chen Chu
- Department of Food Science, Central Taiwan University of Science and Technology, Taichung City 406, Taiwan, ROC
| | - Pei-Ni Chen
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan, ROC
| | - Ying-Jui Ho
- School of Psychology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan, ROC
| | - Ching-Han Yu
- Department of Physiology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan, ROC
| | - Yih-Shou Hsieh
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan, ROC
| | - Dong-Yih Kuo
- Department of Physiology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung City 40201, Taiwan, ROC.
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Yen HH, Roseberry AG. Decreased consumption of rewarding sucrose solutions after injection of melanocortins into the ventral tegmental area of rats. Psychopharmacology (Berl) 2015; 232:285-94. [PMID: 24985892 DOI: 10.1007/s00213-014-3663-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 06/11/2014] [Indexed: 01/25/2023]
Abstract
RATIONALE The mesolimbic dopamine system is an important component of the neural circuitry controlling reward-related behavior. We have recently shown that the melanocortin peptides decrease normal homeostatic feeding through actions in the ventral tegmental area. It is unknown, however, whether melanocortin peptides can also act on dopamine pathways to regulate hedonic, reward-related aspects of feeding. OBJECTIVES In these studies, we tested whether injection of melanocortin receptor agonists directly into the ventral tegmental area (VTA) affected the intake of appetizing and rewarding sugar solutions in two-bottle choice tests. METHODS Varying doses of the melanocortin receptor agonist, MTII, were injected into the VTA, and the intake of different sugar solutions was measured in two-bottle choice tests to distinguish between potential effects on homeostatic versus hedonic aspects of feeding. In addition, 24-h food intake was measured throughout the experiments. RESULTS Injection of MTII into the VTA dose dependently decreased the intake of 1 and 2 % sucrose solutions and 0.2 % saccharin solutions and decreased 24-h food intake in each study. Although MTII also decreased the intake of a 10 % sucrose solution, MTII appeared to be less potent in rats exposed to 10 % sucrose, as only the highest dose of MTII tested was effective at reducing 10 % sucrose intake and food intake in these rats. CONCLUSIONS These studies demonstrate that melanocortins can act directly in the VTA to control reward-related feeding. Thus, these studies add to the growing body of evidence showing that melanocortins can interact with the mesolimbic dopamine system to regulate multiple reward-related behaviors.
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Affiliation(s)
- Haw-Han Yen
- Department of Biology, Georgia State University, 24 Peachtree Center Ave NE, Suite 430SA, Atlanta, GA, 30303, USA
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Girardet C, Mavrikaki M, Southern MR, Smith RG, Butler AA. Assessing interactions between Ghsr and Mc3r reveals a role for AgRP in the expression of food anticipatory activity in male mice. Endocrinology 2014; 155:4843-55. [PMID: 25211592 PMCID: PMC4239417 DOI: 10.1210/en.2014-1497] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The stomach hormone ghrelin and hypothalamic melanocortin neurons belong to a gut-brain circuit controlling appetite and metabolic homeostasis. Mice lacking melanocortin-3 receptor (Mc3rKO) or growth hormone secretagogue receptor (GhsrKO) genes exhibit attenuated food anticipatory activity (FAA), a rise in locomotor activity anticipating mealtime, suggesting common circuitry regulating anticipatory responses to nutrient loading. To investigate the interaction between Ghsrs and Mc3rs, we compared food anticipatory responses in GhsrKO, Mc3rKO, and double Ghsr;Mc3r knockout (DKO) mice subjected to a hypocaloric restricted feeding (RF) protocol in constant dark or 12-hour light, 12-hour dark settings. DKO are viable, exhibiting no overt behavioral or metabolic phenotypes in ad libitum or fasting conditions. FAA was initially attenuated in all mutant strains in constant darkness. However, GhsrKO eventually exhibited a robust food anticipatory response, suggesting compensation. Mc3rKO and DKO did not compensate, indicating a continued requirement for Mc3rs in maintaining the expression of FAA in situations of RF. Abnormal regulation of hypothalamic agouti-related peptide/neuropeptide Y (AgRP/Npy) neurons previously observed during fasting may contribute to attenuated FAA in Mc3rKO. AgRP and Npy expression measured 1 hour before food presentation correlated positively with FAA. Absence of Mc3rs (but not Ghsrs) was associated with lower AgRP/Npy expression, suggesting attenuated responses to signals of negative energy balance. These observations support the importance of Mc3rs as modulators of anticipatory responses to feeding, with mice able to compensate for loss of Ghsrs. The behavioral deficits of Mc3rKO displayed during RF may be partially explained by reduced hunger sensations owing to abnormal regulation of orexigenic AgRP/Npy neurons.
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Affiliation(s)
- Clemence Girardet
- Departments of Metabolism and Aging (C.G., M.M., R.G.S., A.A.B.) and Molecular Therapeutics (M.R.S.), The Scripps Research Institute, Jupiter, Florida 33458; and Department of Pharmacological and Physiological Science (C.G., M.M., A.A.B.), Saint Louis University, Saint Louis, Missouri 63104
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Perino A, Beretta M, Kilić A, Ghigo A, Carnevale D, Repetto IE, Braccini L, Longo D, Liebig-Gonglach M, Zaglia T, Iacobucci R, Mongillo M, Wetzker R, Bauer M, Aime S, Vercelli A, Lembo G, Pfeifer A, Hirsch E. Combined inhibition of PI3Kβ and PI3Kγ reduces fat mass by enhancing α-MSH-dependent sympathetic drive. Sci Signal 2014; 7:ra110. [PMID: 25406378 DOI: 10.1126/scisignal.2005485] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Obesity is defined as an abnormal increase in white adipose tissue and has become a major medical burden worldwide. Signals from the brain control not only appetite but also energy expenditure, both of which contribute to body weight. We showed that genetic or pharmacological inhibition of two phosphatidylinositol 3-kinases (PI3Kβ and PI3Kγ) in mice reduced fat mass by promoting increased energy expenditure. This effect was accompanied by stimulation of lipolysis and the acquisition of the energy-burning characteristics of brown adipocytes by white adipocytes, a process referred to as "browning." The browning of the white adipocytes involved increased norepinephrine release from the sympathetic nervous system. We found that PI3Kβ and PI3Kγ together promoted a negative feedback loop downstream of the melanocortin 4 receptor in the central nervous system, which controls appetite and energy expenditure in the periphery. Analysis of mice with drug-induced sympathetic denervation suggested that these kinases controlled the sympathetic drive in the brain. Administration of inhibitors of both PI3Kβ and PI3Kγ to mice by intracerebroventricular delivery induced a 10% reduction in fat mass as quickly as 10 days. These results suggest that combined inhibition of PI3Kβ and PI3Kγ might represent a promising treatment for obesity.
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Affiliation(s)
- Alessia Perino
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy.
| | - Martina Beretta
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy. Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, D-07747 Jena, Germany
| | - Ana Kilić
- Institute of Pharmacology and Toxicology, University of Bonn, 53127 Bonn, Germany
| | - Alessandra Ghigo
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy
| | - Daniela Carnevale
- Department of Molecular Medicine, "Sapienza" University of Rome, 00161 Rome, Italy. Department of Angiocardioneurology and Translational Medicine, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, 86077 Pozzilli (IS), Italy
| | - Ivan Enrico Repetto
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of Turin, 10043 Turin, Italy
| | - Laura Braccini
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy
| | - Dario Longo
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy
| | | | - Tania Zaglia
- Venetian Institute of Molecular Medicine, University of Padova, 35129 Padova, Italy
| | - Roberta Iacobucci
- Department of Angiocardioneurology and Translational Medicine, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, 86077 Pozzilli (IS), Italy
| | - Marco Mongillo
- Department of Biomedical Sciences and Venetian Institute of Molecular Medicine, University of Padova, 35121 Padova, Italy
| | - Reinhard Wetzker
- Department of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, 07745 Jena, Germany
| | - Michael Bauer
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, D-07747 Jena, Germany
| | - Silvio Aime
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy
| | - Alessandro Vercelli
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of Turin, 10043 Turin, Italy
| | - Giuseppe Lembo
- Department of Molecular Medicine, "Sapienza" University of Rome, 00161 Rome, Italy. Department of Angiocardioneurology and Translational Medicine, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, 86077 Pozzilli (IS), Italy
| | - Alexander Pfeifer
- Institute of Pharmacology and Toxicology, University of Bonn, 53127 Bonn, Germany.
| | - Emilio Hirsch
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy.
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Zeng R, Zhang Y, Du P. SNPs of melanocortin 4 receptor (MC4R) associated with body weight in Beagle dogs. Exp Anim 2014; 63:73-8. [PMID: 24521865 PMCID: PMC4160929 DOI: 10.1538/expanim.63.73] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Melanocortin 4 receptor (MC4R), which is associated with inherited human obesity, is involoved in food intake and body weight of mammals. To study the relationships between MC4R gene polymorphism and body weight in Beagle dogs, we detected and compared the nucleotide sequence of the whole coding region and 3'- and 5'- flanking regions of the dog MC4R gene (1214 bp). In 120 Beagle dogs, two SNPs (A420C, C895T) were identified and their relation with body weight was analyzed with RFLP-PCR method. The results showed that the SNP at A420C was significantly associated with canine body weight trait when it changed amino acid 101 of the MC4R protein from asparagine to threonine, while canine body weight variations were significant in female dogs when MC4R nonsense mutation at C895T. It suggested that the two SNPs might affect the MC4R gene's function which was relative to body weight in Beagle dogs. Therefore, MC4R was a candidate gene for selecting different size dogs with the MC4R SNPs (A420C, C895T) being potentially valuable as a genetic marker.
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Affiliation(s)
- Ruixia Zeng
- Department of Human Anatomy, School of Basic Medical Sciences, Liaoning Medical University, Jinzhou 121001, P.R. China
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46
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Monge-Roffarello B, Labbe SM, Roy MC, Lemay ML, Coneggo E, Samson P, Lanfray D, Richard D. The PVH as a site of CB1-mediated stimulation of thermogenesis by MC4R agonism in male rats. Endocrinology 2014; 155:3448-58. [PMID: 24949658 DOI: 10.1210/en.2013-2092] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The present study was designed to investigate the involvement of the cannabinoid receptor 1 (CB1) in the stimulating effects of the melanocortin-4 receptor (MC4R) agonism on whole-body and brown adipose tissue (BAT) thermogenesis. In a first series of experiments, whole-body and BAT thermogenesis were investigated in rats infused in the third ventricle of the brain with the MC4R agonist melanotan II (MTII) and the CB1 agonist δ9-tetrahydrocannabinol (δ(9)-THC) or the CB1 antagonist AM251. Whole-body thermogenesis was measured by indirect calorimetry and BAT thermogenesis assessed from interscapular BAT (iBAT) temperature. δ(9)-THC blunted the effects of MTII on energy expenditure and iBAT temperature, whereas AM251 tended to potentiate the MTII effects. δ(9)-THC also blocked the stimulating effect of MTII on (14)C-bromopalmitate and (3)H-deoxyglucose uptakes in iBAT. Additionally, δ(9)-THC attenuated the stimulating effect of MTII on the expression of peroxisome proliferator-activated receptor-γ coactivator 1-α (Pgc1α), type II iodothyronine deiodinase (Dio2), carnitine palmitoyltransferase 1B (Cpt1b), and uncoupling protein 1 (Ucp1). In a second series of experiments, we addressed the involvement of the paraventricular hypothalamic nucleus (PVH) in the CB1-mediated effects of MTII on iBAT thermogenesis, which were assessed following the infusion of MTII in the PVH and δ(9)-THC or AM251 in the fourth ventricle of the brain. We demonstrated the ability of δ(9)-THC to blunt MTII-induced iBAT temperature elevation. δ(9)-THC also blocked the PVH effect of MTII on (14)C-bromopalmitate uptake as well as on Pgc1α and Dio2 expression in iBAT. Altogether the results of this study demonstrate the involvement of the PVH in the CB1-mediated stimulating effects of the MC4R agonist MTII on whole-body and BAT thermogenesis.
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MESH Headings
- Adipose Tissue, Brown/metabolism
- Animals
- Male
- Paraventricular Hypothalamic Nucleus/metabolism
- Peptides, Cyclic/metabolism
- Piperidines
- Pyrazoles
- Rats
- Rats, Wistar
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Melanocortin, Type 4/agonists
- Receptor, Melanocortin, Type 4/metabolism
- Thermogenesis
- alpha-MSH/analogs & derivatives
- alpha-MSH/metabolism
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Affiliation(s)
- Boris Monge-Roffarello
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada G1V 4G5
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Monge-Roffarello B, Labbe SM, Lenglos C, Caron A, Lanfray D, Samson P, Richard D. The medial preoptic nucleus as a site of the thermogenic and metabolic actions of melanotan II in male rats. Am J Physiol Regul Integr Comp Physiol 2014; 307:R158-66. [DOI: 10.1152/ajpregu.00059.2014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The present study was designed to investigate the role of the medial preoptic nucleus (MPO) as a site of the thermogenic and metabolic effects of the α-melanocyte-stimulating hormone analog melanotan II (MTII). We also assessed the involvement of the dorsomedial hypothalamic nucleus (DMH) by investigating the effects of the MPO infusion of MTII in rats with DMH lesions produced by kainic acid. Infusion of MTII in the MPO led to increases in interscapular brown adipose tissue (iBAT) temperature and iBAT uptake of 14C-bromopalmitate. Both increases were blocked by DMH lesions. iBAT temperature increase (area under curve) and 14C-bromopalmitate uptake emerged as two correlated variables ( r = 0.63, P < 0.001). DMH lesions also blocked MTII-induced expression of mRNAs coding for proteins involved in 1) thermogenesis [type II iodothyronine deiodinase ( Dio2) and peroxisome proliferator-activated receptor gamma coactivator 1-α ( Pgc1α)], 2) lipolysis [hormone-sensitive lipase ( Hsl)], and 3) lipogenesis [diacylglycerol-O-acyltransferase 2 ( Dgat2), fatty acid synthase ( Fas)], in iBAT of rats killed 1 h after MPO infusion of MTII. MTII also stimulated expression of genes in iWAT but only in rats with DMH lesions. These genes included glucose transporter member 4 ( Glut4), glycerol-3-phosphate acyltransferase 3 ( Gpat3), Dgat1, Dgat2, triglyceride lipase ( Atgl), Hsl, and carnitine palmitoyltransferase 1β ( Cpt1β). Altogether, the present results reveal the MPO as a site of the thermogenic and metabolic actions of MTII. They also contribute to establish the MPO-DMH duet as a significant target for melanocortins to modulate energy homeostasis.
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Affiliation(s)
- Boris Monge-Roffarello
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Sebastien M. Labbe
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Christophe Lenglos
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Alexandre Caron
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Damien Lanfray
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Pierre Samson
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Denis Richard
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
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Girardet C, Begriche K, Ptitsyn A, Koza RA, Butler AA. Unravelling the mysterious roles of melanocortin-3 receptors in metabolic homeostasis and obesity using mouse genetics. INTERNATIONAL JOURNAL OF OBESITY SUPPLEMENTS 2014; 4:S37-44. [PMID: 27152165 DOI: 10.1038/ijosup.2014.10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The central nervous melanocortin system maintains body mass and adiposity within a 'healthy' range by regulating satiety and metabolic homeostasis. Neural melanocortin-4 receptors (MC4R) modulate satiety signals and regulate autonomic outputs governing glucose and lipid metabolism in the periphery. The functions of melanocortin-3 receptors (MC3R) have been less well defined. We have observed that food anticipatory activity (FAA) is attenuated in Mc3r-/- mice housed in light:dark or constant dark conditions. Mc3r-/- mice subjected to the restricted feeding protocol that was used to induce FAA also developed insulin resistance, dyslipidaemia, impaired glucose tolerance and evidence of a cellular stress response in the liver. MC3Rs may thus function as modulators of oscillator systems that govern circadian rhythms, integrating signals from nutrient sensors to facilitate synchronizing peak foraging behaviour and metabolic efficiency with nutrient availability. To dissect the functions of MC3Rs expressed in hypothalamic and extra-hypothalamic structures, we inserted a 'lox-stop-lox' (TB) sequence into the Mc3r gene. Mc3r (TB/TB) mice recapitulate the phenotype reported for Mc3r-/- mice: increased adiposity, accelerated diet-induced obesity and attenuated FAA. The ventromedial hypothalamus exhibits high levels of Mc3r expression; however, restoring the expression of the LoxTB Mc3r allele in this nucleus did not restore FAA. However, a surprising outcome came from studies using Nestin-Cre to restore the expression of the LoxTB Mc3r allele in the nervous system. These data suggest that 'non-neural' MC3Rs have a role in the defence of body weight. Future studies examining the homeostatic functions of MC3Rs should therefore consider actions outside the central nervous system.
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Affiliation(s)
- C Girardet
- Department of Metabolism and Aging, The Scripps Research Institute , Jupiter, FL, USA
| | - K Begriche
- Department of Metabolism and Aging, The Scripps Research Institute , Jupiter, FL, USA
| | - A Ptitsyn
- The Pennington Biomedical Research Center, Louisiana State University System , Baton Rouge, LA, USA
| | - R A Koza
- The Pennington Biomedical Research Center, Louisiana State University System , Baton Rouge, LA, USA
| | - A A Butler
- Department of Metabolism and Aging, The Scripps Research Institute , Jupiter, FL, USA
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The neuroanatomical function of leptin in the hypothalamus. J Chem Neuroanat 2014; 61-62:207-20. [PMID: 25007719 DOI: 10.1016/j.jchemneu.2014.05.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Revised: 05/09/2014] [Accepted: 05/28/2014] [Indexed: 02/07/2023]
Abstract
The anorexigenic hormone leptin plays an important role in the control of food intake and feeding-related behavior, for an important part through its action in the hypothalamus. The adipose-derived hormone modulates a complex network of several intercommunicating orexigenic and anorexigenic neuropeptides in the hypothalamus to reduce food intake and increase energy expenditure. In this review we present an updated overview of the functional role of leptin in respect to feeding and feeding-related behavior per distinct hypothalamic nuclei. In addition to the arcuate nucleus, which is a major leptin sensitive hub, leptin-responsive neurons in other hypothalamic nuclei, including the, dorsomedial-, ventromedial- and paraventricular nucleus and the lateral hypothalamic area, are direct targets of leptin. However, leptin also modulates hypothalamic neurons in an indirect manner, such as via the melanocortin system. The dissection of the complexity of leptin's action on the networks involved in energy balance is subject of recent and future studies. A full understanding of the role of hypothalamic leptin in the regulation of energy balance requires cell-specific manipulation using of conditional deletion and expression of leptin receptors. In addition, optogenetic and pharmacogenetic tools in combination with other pharmacological (such as the recent discovery of a leptin receptor antagonist) and neuronal tracing techniques to map the circuit, will be helpful to understand the role of leptin receptor expressing neurons. Better understanding of these circuits and the involvement of leptin could provide potential sites for therapeutic interventions in obesity and metabolic diseases characterized by dysregulation of energy balance.
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Gallo-Payet N. Central (mainly) actions of GPCRs in energy homeostasis/balance: view from the Chair. INTERNATIONAL JOURNAL OF OBESITY SUPPLEMENTS 2014; 4:S21-5. [PMID: 27152161 DOI: 10.1038/ijosup.2014.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To maintain a constant body weight, energy intake must equal energy expenditure; otherwise, there is a risk of overweight and obesity. The hypothalamus is one of the primary brain regions where multiple nutrient-related signals from peripheral and central sources converge and become integrated to regulate both short- and long-term nutritional states. The aim of the afternoon session of the 15th Annual International Symposium of the Laval University Obesity Research Chair held in Quebec City on 9 November 2012 was to present the most recent insights into the complex molecular mechanisms regulating food intake. The aims were to emphasize on the interaction between central and peripheral actions of some of the key players acting not only at the hypothalamic level but also at the periphery. Presentations were focused on melanocortin-3 receptor (MC3R) and melanin-concentrating hormone (MCH) as anorexigenic and orexigenic components of the hypothalamus, on endocannabinoid receptors, initially as a central neuromodulatory signal, and on glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP) as peripheral signals. What becomes clear from these four presentations is that the regulation of food intake and energy homeostasis involves several overlapping pathways, and that we have only touched the tip of the iceberg. From the examples presented in this symposium, it could be expected that in the near future, in addition to a low-fat diet and exercise, a combination of appropriate peptides and small molecules is likely to become available to improve/facilitate the objectives of long-term maintenance of energy balance and body weight.
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Affiliation(s)
- N Gallo-Payet
- Division of Endocrinology, Department of Medicine, Faculté de médecine et des sciences de la santé, Université de Sherbrooke , Sherbrooke, Quebec, Canada
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