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Guan D, Men Y, Bartlett A, Hernández MAS, Xu J, Yi X, Li HS, Kong D, Mazitschek R, Ozcan U. Central inhibition of HDAC6 re-sensitizes leptin signaling during obesity to induce profound weight loss. Cell Metab 2024; 36:857-876.e10. [PMID: 38569472 DOI: 10.1016/j.cmet.2024.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 11/02/2023] [Accepted: 02/13/2024] [Indexed: 04/05/2024]
Abstract
Leptin resistance during excess weight gain significantly contributes to the recidivism of obesity to leptin-based pharmacological therapies. The mechanisms underlying the inhibition of leptin receptor (LepR) signaling during obesity are still elusive. Here, we report that histone deacetylase 6 (HDAC6) interacts with LepR, reducing the latter's activity, and that pharmacological inhibition of HDAC6 activity disrupts this interaction and augments leptin signaling. Treatment of diet-induced obese mice with blood-brain barrier (BBB)-permeable HDAC6 inhibitors profoundly reduces food intake and leads to potent weight loss without affecting the muscle mass. Genetic depletion of Hdac6 in Agouti-related protein (AgRP)-expressing neurons or administration with BBB-impermeable HDAC6 inhibitors results in a lack of such anti-obesity effect. Together, these findings represent the first report describing a mechanistically validated and pharmaceutically tractable therapeutic approach to directly increase LepR activity as well as identifying centrally but not peripherally acting HDAC6 inhibitors as potent leptin sensitizers and anti-obesity agents.
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Affiliation(s)
- Dongxian Guan
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yuqin Men
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Alexander Bartlett
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Jie Xu
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Xinchi Yi
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Hu-Song Li
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Dong Kong
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ralph Mazitschek
- Massachusetts General Hospital, Center for Systems Biology, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Umut Ozcan
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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2
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Feng J, Jia T, Ren Y, Zhang H, Zhu W. Methylation of the leptin gene promoter is associated with a negative correlation between leptin concentration and body fat in Tupaia belangeri. Life Sci 2024; 336:122323. [PMID: 38042285 DOI: 10.1016/j.lfs.2023.122323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 11/20/2023] [Accepted: 11/29/2023] [Indexed: 12/04/2023]
Abstract
AIMS Leptin is a signaling protein secreted by white adipose tissue encoded by the obesity gene, and its main function is to regulate the food intake and energy metabolism in mammals. Previous studies had found that animal leptin concentration was positively correlated with its body fat, but the leptin concentration of Tupaia belangeri was negatively correlated with its body fat mass. The present study attempted to investigate the mechanisms of leptin concentration negatively correlated with its body fat mass in T. belangeri. MATERIAL AND METHODS We measured the leptin concentration of the two groups of animals by enzyme linked immunosorbent assay (ELISA) and quantified the leptin mRNA expression by qPCR. Then, the histological, transcriptomic, and bisulfite sequencing of the two groups of animals were studied. Moreover, to investigate the energy metabolism under the negative correlation, we also analyzed the metabolomics and metabolic rate in T. belangeri. KEY FINDINGS We revealed the negative correlation was mediated by leptin gene methylation of subcutaneous adipose tissue. Further, we also found that T. belangeri increased energy metabolism with leptin decreased. SIGNIFICANCE We challenge the traditional view that leptin concentration was positively correlated with body fat mass, and further revealed its molecular mechanism and energy metabolism strategy. This special leptin secretion mechanism and energy metabolism strategy enriched our understanding of energy metabolism of animals, which provided an opportunity for the clinical transformation of metabolic diseases.
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Affiliation(s)
- Jiahong Feng
- Key Laboratory of Ecological Adaptive Evolution and Conservation on Animals-Plants in Southwest Mountain Ecosystem of Yunnan Province Higher Institutes College, School of Life Sciences, Yunnan Normal University, Kunming 650500, Yunnan, China
| | - Ting Jia
- Key Laboratory of Ecological Adaptive Evolution and Conservation on Animals-Plants in Southwest Mountain Ecosystem of Yunnan Province Higher Institutes College, School of Life Sciences, Yunnan Normal University, Kunming 650500, Yunnan, China
| | - Yue Ren
- Shanxi Agricultural University, Taiyuan 030024, Shanxi, China
| | - Hao Zhang
- Key Laboratory of Ecological Adaptive Evolution and Conservation on Animals-Plants in Southwest Mountain Ecosystem of Yunnan Province Higher Institutes College, School of Life Sciences, Yunnan Normal University, Kunming 650500, Yunnan, China
| | - Wanlong Zhu
- Key Laboratory of Ecological Adaptive Evolution and Conservation on Animals-Plants in Southwest Mountain Ecosystem of Yunnan Province Higher Institutes College, School of Life Sciences, Yunnan Normal University, Kunming 650500, Yunnan, China; Engineering Research Center of Sustainable Development and Utilization of Biomass Energy Ministry of Education, Yunnan Normal University, Kunming 650500, Yunnan, China; Key Laboratory of Yunnan Province for Biomass Energy and Environment Biotechnology, Kunming 650500, Yunnan, China.
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3
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Umbayev B, Saliev T, Safarova (Yantsen) Y, Yermekova A, Olzhayev F, Bulanin D, Tsoy A, Askarova S. The Role of Cdc42 in the Insulin and Leptin Pathways Contributing to the Development of Age-Related Obesity. Nutrients 2023; 15:4964. [PMID: 38068822 PMCID: PMC10707920 DOI: 10.3390/nu15234964] [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] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/22/2023] [Accepted: 11/26/2023] [Indexed: 12/18/2023] Open
Abstract
Age-related obesity significantly increases the risk of chronic diseases such as type 2 diabetes, cardiovascular diseases, hypertension, and certain cancers. The insulin-leptin axis is crucial in understanding metabolic disturbances associated with age-related obesity. Rho GTPase Cdc42 is a member of the Rho family of GTPases that participates in many cellular processes including, but not limited to, regulation of actin cytoskeleton, vesicle trafficking, cell polarity, morphology, proliferation, motility, and migration. Cdc42 functions as an integral part of regulating insulin secretion and aging. Some novel roles for Cdc42 have also been recently identified in maintaining glucose metabolism, where Cdc42 is involved in controlling blood glucose levels in metabolically active tissues, including skeletal muscle, adipose tissue, pancreas, etc., which puts this protein in line with other critical regulators of glucose metabolism. Importantly, Cdc42 plays a vital role in cellular processes associated with the insulin and leptin signaling pathways, which are integral elements involved in obesity development if misregulated. Additionally, a change in Cdc42 activity may affect senescence, thus contributing to disorders associated with aging. This review explores the complex relationships among age-associated obesity, the insulin-leptin axis, and the Cdc42 signaling pathway. This article sheds light on the vast molecular web that supports metabolic dysregulation in aging people. In addition, it also discusses the potential therapeutic implications of the Cdc42 pathway to mitigate obesity since some new data suggest that inhibition of Cdc42 using antidiabetic drugs or antioxidants may promote weight loss in overweight or obese patients.
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Affiliation(s)
- Bauyrzhan Umbayev
- National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan; (Y.S.); (A.Y.); (F.O.); (A.T.); (S.A.)
| | - Timur Saliev
- S.D. Asfendiyarov Kazakh National Medical University, Almaty 050012, Kazakhstan;
| | - Yuliya Safarova (Yantsen)
- National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan; (Y.S.); (A.Y.); (F.O.); (A.T.); (S.A.)
| | - Aislu Yermekova
- National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan; (Y.S.); (A.Y.); (F.O.); (A.T.); (S.A.)
| | - Farkhad Olzhayev
- National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan; (Y.S.); (A.Y.); (F.O.); (A.T.); (S.A.)
| | - Denis Bulanin
- Department of Biomedical Sciences, School of Medicine, Nazarbayev University, Astana 010000, Kazakhstan;
| | - Andrey Tsoy
- National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan; (Y.S.); (A.Y.); (F.O.); (A.T.); (S.A.)
| | - Sholpan Askarova
- National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan; (Y.S.); (A.Y.); (F.O.); (A.T.); (S.A.)
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4
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Kian N, Bagheri A, Salmanpour F, Soltani A, Mohajer Z, Samieefar N, Barekatain B, Kelishadi R. Breast feeding, obesity, and asthma association: clinical and molecular views. Clin Mol Allergy 2023; 21:8. [PMID: 37789370 PMCID: PMC10546753 DOI: 10.1186/s12948-023-00189-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 08/28/2023] [Indexed: 10/05/2023] Open
Abstract
Asthma is a chronic condition that affects children worldwide. Accumulating number of studies reported that the prevalence of pediatric obesity and asthma might be altered through breastfeeding. It has been proposed that Leptin, which exists in human milk, is oppositely associated with weight increase in newborns. It may also influence peripheral immune system by promoting TH1 responses and suppressing TH2 cytokines. Leptin influences body weight and immune responses through complex signaling pathways at molecular level. Although previous studies provide explanations for the protective role of breastfeeding against both obesity and asthma, other factors such as duration of breastfeeding, parental, and prenatal factors may confound this relationship which requires further research.
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Affiliation(s)
- Naghmeh Kian
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Alireza Bagheri
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Iran
| | - Fardis Salmanpour
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- Student Research Committee, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Afsaneh Soltani
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Zahra Mohajer
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Noosha Samieefar
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Behzad Barekatain
- Division of Neonatology, Department of Pediatrics, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Roya Kelishadi
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran.
- Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
- USERN Office, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
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Gorji AE, Ostaszewski P, Urbańska K, Sadkowski T. Does β-Hydroxy-β-Methylbutyrate Have Any Potential to Support the Treatment of Duchenne Muscular Dystrophy in Humans and Animals? Biomedicines 2023; 11:2329. [PMID: 37626825 PMCID: PMC10452677 DOI: 10.3390/biomedicines11082329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/14/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
Skeletal muscle is the protein reservoir of our body and an important regulator of glucose and lipid homeostasis. The dystrophin gene is the largest gene and has a key role in skeletal muscle construction and function. Mutations in the dystrophin gene cause Duchenne and Becker muscular dystrophy in humans, mice, dogs, and cats. Duchenne muscular dystrophy (DMD) is an X-linked neuromuscular condition causing progressive muscle weakness and premature death. β-hydroxy β-methylbutyrate (HMB) prevents deleterious muscle responses under pathological conditions, including tumor and chronic steroid therapy-related muscle losses. The use of HMB as a dietary supplement allows for increasing lean weight gain; has a positive immunostimulatory effect; is associated with decreased mortality; and attenuates sarcopenia in elderly animals and individuals. This study aimed to identify some genes, metabolic pathways, and biological processes which are common for DMD and HMB based on existing literature and then discuss the consequences of that interaction.
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Affiliation(s)
- Abdolvahab Ebrahimpour Gorji
- Department of Physiological Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-776 Warsaw, Poland; (A.E.G.); (P.O.)
| | - Piotr Ostaszewski
- Department of Physiological Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-776 Warsaw, Poland; (A.E.G.); (P.O.)
| | - Kaja Urbańska
- Department of Morphological Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-776 Warsaw, Poland;
| | - Tomasz Sadkowski
- Department of Physiological Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-776 Warsaw, Poland; (A.E.G.); (P.O.)
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6
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Targeting PI3K/AKT signaling pathway in obesity. Biomed Pharmacother 2023; 159:114244. [PMID: 36638594 DOI: 10.1016/j.biopha.2023.114244] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/13/2023] Open
Abstract
Obesity is a disorder with an increasing prevalence, which impairs the life quality of patients and intensifies societal health care costs. The development of safe and innovative prevention strategies and therapeutic approaches is thus of great importance. The complex pathophysiology of obesity involves multiple signaling pathways that influence energy metabolism in different tissues. The phosphatidylinositol 3-kinases (PI3K)/protein kinase B (AKT) pathway is critical for the metabolic homeostasis and its function in insulin-sensitive tissues is described in the context of health, obesity and obesity-related complications. The PI3K family participates in the regulation of diverse physiological processes including but not limited to cell growth, survival, differentiation, autophagy, chemotaxis, and metabolism depending on the cellular context. AKT is downstream of PI3K in the insulin signaling pathway, and promotes multiple cellular processes by targeting a plethora of regulatory proteins that control glucose and lipid metabolism. Natural products are essential for prevention and treatment of many human diseases, including obesity. Anti-obesity natural compounds effect multiple pathophysiological mechanisms involved in obesity development. Numerous recent preclinical studies reveal the advances in using plant secondary metabolites to target the PI3K/AKT signaling pathway for obesity management. In this paper the druggability of PI3K as a target for compounds with anti-obesity potential is evaluated. Perspectives on the strategies and limitations for clinical implementation of obesity management using natural compounds modulating the PI3K/AKT pathway are suggested.
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7
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Liu J, Lai F, Hou Y, Zheng R. Leptin signaling and leptin resistance. MEDICAL REVIEW (BERLIN, GERMANY) 2022; 2:363-384. [PMID: 37724323 PMCID: PMC10388810 DOI: 10.1515/mr-2022-0017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/12/2022] [Indexed: 09/20/2023]
Abstract
With the prevalence of obesity and associated comorbidities, studies aimed at revealing mechanisms that regulate energy homeostasis have gained increasing interest. In 1994, the cloning of leptin was a milestone in metabolic research. As an adipocytokine, leptin governs food intake and energy homeostasis through leptin receptors (LepR) in the brain. The failure of increased leptin levels to suppress feeding and elevate energy expenditure is referred to as leptin resistance, which encompasses complex pathophysiological processes. Within the brain, LepR-expressing neurons are distributed in hypothalamus and other brain areas, and each population of the LepR-expressing neurons may mediate particular aspects of leptin effects. In LepR-expressing neurons, the binding of leptin to LepR initiates multiple signaling cascades including janus kinase (JAK)-signal transducers and activators of transcription (STAT) phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT), extracellular regulated protein kinase (ERK), and AMP-activated protein kinase (AMPK) signaling, etc., mediating leptin actions. These findings place leptin at the intersection of metabolic and neuroendocrine regulations, and render leptin a key target for treating obesity and associated comorbidities. This review highlights the main discoveries that shaped the field of leptin for better understanding of the mechanism governing metabolic homeostasis, and guides the development of safe and effective interventions to treat obesity and associated diseases.
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Affiliation(s)
- Jiarui Liu
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Futing Lai
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Yujia Hou
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Ruimao Zheng
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
- Neuroscience Research Institute, Peking University, Beijing, China
- Key Laboratory for Neuroscience of Ministry of Education, Peking University, Beijing, China
- Key Laboratory for Neuroscience of National Health Commission, Peking University, Beijing 100191, China
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8
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Iqbal J, Jiang HL, Wu HX, Li L, Zhou YH, Hu N, Xiao F, Wang T, Xu SN, Zhou HD. Hereditary severe insulin resistance syndrome: Pathogenesis, pathophysiology, and clinical management. Genes Dis 2022. [PMID: 37492723 PMCID: PMC10363564 DOI: 10.1016/j.gendis.2022.03.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Severe insulin resistance has been linked to some of the most globally prevalent disorders, such as diabetes mellitus, nonalcoholic fatty liver disease, polycystic ovarian syndrome, and hypertension. Hereditary severe insulin resistance syndrome (H-SIRS) is a rare disorder classified into four principal categories: primary insulin receptor defects, lipodystrophies, complex syndromes, and obesity-related H-SIRS. Genes such as INSR, AKT2, TBC1D4, AGPAT2, BSCL2, CAV1, PTRF, LMNA, PPARG, PLIN1, CIDEC, LIPE, PCYT1A, MC4R, LEP, POMC, SH2B1, RECQL2, RECQL3, ALMS1, PCNT, ZMPSTE24, PIK3R1, and POLD1 have been linked to H-SIRS. Its clinical features include insulin resistance, hyperglycemia, hyperandrogenism, severe dyslipidemia, fatty liver, abnormal topography of adipose tissue, and low serum leptin and adiponectin levels. Diagnosis of H-SIRS is based on the presence of typical clinical features associated with the various H-SIRS forms and the identification of mutations in H-SIRS-linked genes by genetic testing. Diet therapy, insulin sensitization, exogenous insulin therapy, and leptin replacement therapy have widely been adopted to manage H-SIRS. The rarity of H-SIRS, its highly variable clinical presentation, refusal to be tested for genetic mutations by patients' family members who are not severely sick, unavailability of genetic testing, and testing expenses contribute to the delayed or underdiagnoses of H-SIRS. Early diagnosis facilitates early management of the condition, which results in improved glycemic control and delayed onset of diabetes and other complications related to severe insulin resistance. The use of updated genetic sequencing technologies is recommended, and long-term studies are required for genotype-phenotype differentiation and formulation of diagnostic and treatment protocols.
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9
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Harvey J. Leptin regulation of synaptic function at hippocampal TA-CA1 and SC-CA1 synapses. VITAMINS AND HORMONES 2022; 118:315-336. [PMID: 35180931 DOI: 10.1016/bs.vh.2021.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Increasing evidence indicates that the metabolic hormone, leptin markedly influences the functioning of the hippocampus. In particular, exposure to leptin results in persistent changes in synaptic efficacy at both temporoammonic (TA) and Schaffer Collateral (SC) inputs to hippocampal CA1 neurons. The ability of leptin to regulate TA-CA1 and SC-CA1 synapses has important functional implications, as both synaptic connections play important roles in hippocampal-dependent learning and memory. Here we review the modulatory actions of the hormone leptin at these hippocampal CA1 synapses and explore the impact on learning and memory processes.
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Affiliation(s)
- Jenni Harvey
- Division of Systems Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom.
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10
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Kamstra K, Rizwan MZ, Grattan DR, Horsfield JA, Tups A. Leptin regulates glucose homeostasis via the canonical Wnt pathway in the zebrafish. FASEB J 2022; 36:e22207. [PMID: 35188286 DOI: 10.1096/fj.202101764r] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/12/2022] [Accepted: 02/01/2022] [Indexed: 11/11/2022]
Abstract
Leptin is best known for its role in adipostasis, but it also regulates blood glucose levels. The molecular mechanism by which leptin controls glucose homeostasis remains largely unknown. Here, we use a zebrafish model to show that Wnt signaling mediates the glucoregulatory effects of leptin. Under normal feeding conditions, leptin regulates glucose homeostasis but not adipostasis in zebrafish. In times of nutrient excess, however, we found that leptin also regulates body weight and size. Using a Wnt signaling reporter fish, we show that leptin activates the canonical Wnt pathway in vivo. Utilizing two paradigms for hyperglycemia, it is revealed that leptin regulates glucose homeostasis via the Wnt pathway, as pharmacological inhibition of this pathway impairs the glucoregulatory actions of leptin. Our results may shed new light on the evolution of the physiological function of leptin.
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Affiliation(s)
- Kaj Kamstra
- Centre for Neuroendocrinology and Brain Health Research Centre, University Otago, Dunedin, New Zealand.,Department of Physiology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Mohammed Z Rizwan
- Centre for Neuroendocrinology and Brain Health Research Centre, University Otago, Dunedin, New Zealand.,Department of Anatomy, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - David R Grattan
- Centre for Neuroendocrinology and Brain Health Research Centre, University Otago, Dunedin, New Zealand.,Department of Anatomy, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Julia A Horsfield
- Department of Pathology, University of Otago, Dunedin, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - Alexander Tups
- Centre for Neuroendocrinology and Brain Health Research Centre, University Otago, Dunedin, New Zealand.,Department of Physiology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
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11
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Vohra MS, Benchoula K, Serpell CJ, Hwa WE. AgRP/NPY and POMC neurons in the arcuate nucleus and their potential role in treatment of obesity. Eur J Pharmacol 2022; 915:174611. [PMID: 34798121 DOI: 10.1016/j.ejphar.2021.174611] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 10/27/2021] [Accepted: 10/27/2021] [Indexed: 02/08/2023]
Abstract
Obesity is a major health crisis affecting over a third of the global population. This multifactorial disease is regulated via interoceptive neural circuits in the brain, whose alteration results in excessive body weight. Certain central neuronal populations in the brain are recognised as crucial nodes in energy homeostasis; in particular, the hypothalamic arcuate nucleus (ARC) region contains two peptide microcircuits that control energy balance with antagonistic functions: agouti-related peptide/neuropeptide-Y (AgRP/NPY) signals hunger and stimulates food intake; and pro-opiomelanocortin (POMC) signals satiety and reduces food intake. These neuronal peptides levels react to energy status and integrate signals from peripheral ghrelin, leptin, and insulin to regulate feeding and energy expenditure. To manage obesity comprehensively, it is crucial to understand cellular and molecular mechanisms of information processing in ARC neurons, since these regulate energy homeostasis. Importantly, a specific strategy focusing on ARC circuits needs to be devised to assist in treating obese patients and maintaining weight loss with minimal or no side effects. The aim of this review is to elucidate the recent developments in the study of AgRP-, NPY- and POMC-producing neurons, specific to their role in controlling metabolism. The impact of ghrelin, leptin, and insulin signalling via action of these neurons is also surveyed, since they also impact energy balance through this route. Lastly, we present key proteins, targeted genes, compounds, drugs, and therapies that actively work via these neurons and could potentially be used as therapeutic targets for treating obesity conditions.
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Affiliation(s)
- Muhammad Sufyan Vohra
- School of Medicine, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, 47500, Subang Jaya, Selangor Darul Ehsan, Malaysia
| | - Khaled Benchoula
- School of Medicine, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, 47500, Subang Jaya, Selangor Darul Ehsan, Malaysia
| | - Christopher J Serpell
- School of Physical Sciences, Ingram Building, University of Kent, Canterbury, Kent, CT2 7NH, United Kingdom
| | - Wong Eng Hwa
- School of Medicine, Faculty of Health and Medical Sciences, Taylor's University Lakeside Campus, 47500, Subang Jaya, Selangor Darul Ehsan, Malaysia.
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12
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Xu L, Füredi N, Lutter C, Geenen B, Pétervári E, Balaskó M, Dénes Á, Kovács KJ, Gaszner B, Kozicz T. Leptin coordinates efferent sympathetic outflow to the white adipose tissue through the midbrain centrally-projecting Edinger-Westphal nucleus in male rats. Neuropharmacology 2021; 205:108898. [PMID: 34861283 DOI: 10.1016/j.neuropharm.2021.108898] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 09/29/2021] [Accepted: 11/21/2021] [Indexed: 12/11/2022]
Abstract
The centrally-projecting Edinger-Westphal nucleus (EWcp) hosts a large population of neurons expressing urocortin 1 (Ucn1) and about half of these neurons also express the leptin receptor (LepRb). Previously, we have shown that the peripheral adiposity hormone leptin signaling energy surfeit modulates EWcp neurons' activity. Here, we hypothesized that Ucn1/LepRb neurons in the EWcp would act as a crucial neuronal node in the brain-white adipose tissue (WAT) axis modulating efferent sympathetic outflow to the WAT. We showed that leptin bound to neurons of the EWcp stimulated STAT3 phosphorylation, and increased Ucn1-production in a time-dependent manner. Besides, retrograde transneuronal tract-tracing using pseudorabies virus (PRV) identified EWcp Ucn1 neurons connected to WAT. Interestingly, reducing EWcp Ucn1 contents by ablating EWcp LepRb-positive neurons with leptin-saporin, did not affect food intake and body weight gain, but substantially (+26%) increased WAT weight accompanied by a higher plasma leptin level and changed plasma lipid profile. We also found that ablation of EWcp Ucn1/LepRb neurons resulted in lower respiratory quotient and oxygen consumption one week after surgery, but was comparable to sham values after 3 and 5 weeks of surgery. Taken together, we report that EWcp/LepRb/Ucn1 neurons not only respond to leptin signaling but also control WAT size and fat metabolism without altering food intake. These data suggest the existence of a EWcp-WAT circuitry allowing an organism to recruit fuels without being able to eat in situations such as the fight-or-flight response.
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Affiliation(s)
- Lu Xu
- Department of Anatomy Medical Imaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands; Department of Structural and Cellular Biology, School of Medicine, Tulane University, New Orleans, LA, USA
| | - Nóra Füredi
- Department of Anatomy and Center for Neuroscience, Medical School, Pécs University, Pécs, Hungary; Department of Translational Medicine, Medical School, Pécs University, Pécs, Hungary
| | - Christoph Lutter
- Department of Anatomy and Center for Neuroscience, Medical School, Pécs University, Pécs, Hungary
| | - Bram Geenen
- Department of Anatomy Medical Imaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
| | - Erika Pétervári
- Department of Translational Medicine, Medical School, Pécs University, Pécs, Hungary
| | - Márta Balaskó
- Department of Translational Medicine, Medical School, Pécs University, Pécs, Hungary
| | - Ádám Dénes
- "Momentum" Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Krisztina J Kovács
- Institute of Experimental Medicine, Eötvös Loránd Research Network, Budapest, Hungary
| | - Balázs Gaszner
- Department of Anatomy and Center for Neuroscience, Medical School, Pécs University, Pécs, Hungary.
| | - Tamás Kozicz
- Department of Anatomy Medical Imaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands; Department of Clinical Genomics, Mayo Clinic, MN, USA; Department of Laboratory Medicine and Pathology, Mayo Clinic, MN, USA; Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA.
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13
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Multiple Leptin Signalling Pathways in the Control of Metabolism and Fertility: A Means to Different Ends? Int J Mol Sci 2021; 22:ijms22179210. [PMID: 34502119 PMCID: PMC8430761 DOI: 10.3390/ijms22179210] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/13/2021] [Accepted: 08/23/2021] [Indexed: 01/20/2023] Open
Abstract
The adipocyte-derived ‘satiety promoting’ hormone, leptin, has been identified as a key central regulator of body weight and fertility, such that its absence leads to obesity and infertility. Plasma leptin levels reflect body adiposity, and therefore act as an ‘adipostat’, whereby low leptin levels reflect a state of low body adiposity (under-nutrition/starvation) and elevated leptin levels reflect a state of high body adiposity (over-nutrition/obesity). While genetic leptin deficiency is rare, obesity-related leptin resistance is becoming increasingly common. In the absence of adequate leptin sensitivity, leptin is unable to exert its ‘anti-obesity’ effects, thereby exacerbating obesity. Furthermore, extreme leptin resistance and consequent low or absent leptin signalling resembles a state of starvation and can thus lead to infertility. However, leptin resistance occurs on a spectrum, and it is possible to be resistant to leptin’s metabolic effects while retaining leptin’s permissive effects on fertility. This may be because leptin exerts its modulatory effects on energy homeostasis and reproductive function through discrete intracellular signalling pathways, and these pathways are differentially affected by the molecules that promote leptin resistance. This review discusses the potential mechanisms that enable leptin to exert differential control over metabolic and reproductive function in the contexts of healthy leptin signalling and of diet-induced leptin resistance.
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14
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Barton JR, Snook AE, Waldman SA. From leptin to lasers: the past and present of mouse models of obesity. Expert Opin Drug Discov 2021; 16:777-790. [PMID: 33472452 PMCID: PMC8243785 DOI: 10.1080/17460441.2021.1877654] [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: 09/11/2020] [Accepted: 01/14/2021] [Indexed: 10/22/2022]
Abstract
Introduction: Obesity is a prevalent condition that accounts for significant morbidity and mortality across the globe. Despite substantial effort, most obesity pharmacotherapies have proven unsafe or ineffective. The use of obese mouse models provides unique insight into the hormones and mechanisms that regulate appetite and metabolism. Paramount among these models are the 'obese' and 'diabetic' mice that revealed the powerful satiety hormone leptin, revolutionizing obesity research.Areas Covered: In this article, the authors discuss work on leptin therapy, and the clinical response to leptin in humans. The authors describe the use of modern mouse genetics to study targetable mechanisms for genetic forms of human obesity. Additionally, they describe mouse models of neuromodulation and their utility in unraveling neural circuits that govern appetite and metabolism.Expert opinion: Combining past and present models of obesity is required for the development of safe, effective, and impactful obesity therapy. Current research in obesity can benefit from repositories of genetically engineered mouse models to discover interactions between appetitive systems and circuits. Combining leptin therapy with other satiety signals comprising the gut-brain axis is a promising approach to induce significant enduring weight loss.
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Affiliation(s)
- Joshua R. Barton
- Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Adam E. Snook
- Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Scott A. Waldman
- Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, PA 19107, USA
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15
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Fernandes MF, Lau D, Sharma S, Fulton S. Anxiety-like behavior in female mice is modulated by STAT3 signaling in midbrain dopamine neurons. Brain Behav Immun 2021; 95:391-400. [PMID: 33872705 DOI: 10.1016/j.bbi.2021.04.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 12/13/2022] Open
Abstract
The central signaling actions of cytokines are mediated by signal transducer and activator of transcription (STAT3). STAT3 activation plays a pivotal role in the behavioral responses to the adiposity hormone leptin, including in midbrain dopamine (DA) neurons where it mediates the influence of leptin to diminish physical activity and running reward in male mice. Leptin also has anxiolytic effects which have been tied to the mesolimbic DA system. To assess the contribution of STAT3 signaling in mesolimbic DA neurons on feeding, mesolimbic DA tone and anxiodepressive behaviors in female mice, we generated DA-specific STAT3 knockout mice by crossing mice expressing Cre under the control of the dopamine transporter with STAT3-LoxP mice. Feeding, locomotion, wheel running, conditioned place preference for palatable food and amphetamine locomotor sensitization were unaffected by DA-specific STAT3 deletion. Conversely, knockout mice exhibited heightened anxiety-like behavior (open field test and elevated plus maze) along with increased basal and stress-induced plasma corticosterone, whereas indices of behavioral despair (forced swim and tail-suspension tasks) were unchanged. In accordance with biochemical evidence of increased D1 receptor signaling (phospho-DARPP32Thr34) in the central nucleus of the amygdala (CeA) of knockout mice, local microinjections of a D1 receptor antagonist reversed the anxiogenic phenotype of knockout mice. In addition to alluding to sex differences in the signaling mechanisms mediating anxiety-like behavior, our findings suggest that activation of STAT3 in midbrain dopamine neurons projecting to the CeA dampens anxiety in a D1R-dependent manner in female mice.
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Affiliation(s)
- Maria F Fernandes
- Centre de Recherche du CHUM, Canada; Physiology and Pharmacology, Canada
| | - David Lau
- Centre de Recherche du CHUM, Canada; Neuroscience, Faculty of Medicine, University of Montreal, Québec, Canada
| | - Sandeep Sharma
- Centre de Recherche du CHUM, Canada; Department of Nutrition, Canada
| | - Stephanie Fulton
- Centre de Recherche du CHUM, Canada; Department of Nutrition, Canada; Montreal Diabetes Research Center, Canada; Center for Studies in Behavioural Neurobiology (Concordia University), Canada.
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16
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Berger C, Klöting N. Leptin Receptor Compound Heterozygosity in Humans and Animal Models. Int J Mol Sci 2021; 22:4475. [PMID: 33922961 PMCID: PMC8123313 DOI: 10.3390/ijms22094475] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/14/2021] [Accepted: 04/20/2021] [Indexed: 01/10/2023] Open
Abstract
Leptin and its receptor are essential for regulating food intake, energy expenditure, glucose homeostasis and fertility. Mutations within leptin or the leptin receptor cause early-onset obesity and hyperphagia, as described in human and animal models. The effect of both heterozygous and homozygous variants is much more investigated than compound heterozygous ones. Recently, we discovered a spontaneous compound heterozygous mutation within the leptin receptor, resulting in a considerably more obese phenotype than described for the homozygous leptin receptor deficient mice. Accordingly, we focus on compound heterozygous mutations of the leptin receptor and their effects on health, as well as possible therapy options in human and animal models in this review.
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Affiliation(s)
- Claudia Berger
- Medical Department III, Endocrinology, Nephrology, Rheumatology, CRC1052, University of Leipzig Medical Center, 04103 Leipzig, Germany;
| | - Nora Klöting
- Medical Department III, Endocrinology, Nephrology, Rheumatology, CRC1052, University of Leipzig Medical Center, 04103 Leipzig, Germany;
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at University of Leipzig, 04103 Leipzig, Germany
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17
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Boucsein A, Kamstra K, Tups A. Central signalling cross-talk between insulin and leptin in glucose and energy homeostasis. J Neuroendocrinol 2021; 33:e12944. [PMID: 33615588 DOI: 10.1111/jne.12944] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/10/2021] [Accepted: 01/27/2021] [Indexed: 12/28/2022]
Abstract
Energy homeostasis is controlled by an intricate regulatory system centred in the brain. The peripheral adiposity signals insulin and leptin play a crucial role in this system by informing the brain of the energy status of the body and mediating their catabolic effects through signal transduction in hypothalamic areas that control food intake, energy expenditure and glucose metabolism. Disruptions of insulin and leptin signalling can result in diabetes and obesity. The central signalling cross-talk between insulin and leptin is essential for maintenance of normal healthy energy homeostasis. An important role of leptin in glucoregulation has been revealed. Typically regarded as being controlled by insulin, the control of glucose homeostasis critically depends on functional leptin action. Leptin, on the other hand, is able to lower glucose levels in the absence of insulin, although insulin is necessary for long-term stabilisation of euglycaemia. Evidence from rodent models and human patients suggests that leptin improves insulin sensitivity in type 1 diabetes. The signalling cross-talk between insulin and leptin is likely conveyed by the WNT/β-catenin pathway. Leptin activates WNT/β-catenin signalling, leading to inhibition of glycogen synthase kinase-3β, a key inhibitor of insulin action, thereby facilitating improved insulin signal transduction and sensitisation of insulin action. Interestingly, insights into the roles of insulin and leptin in insects and fish indicate that leptin may have initially evolved as a glucoregulatory hormone and that its anorexigenic and body weight regulatory function was acquired throughout evolution. Furthermore, the regulation of both central and peripheral control of energy homeostasis is tightly controlled by the circadian clock, allowing adaptation of homeostatic processes to environmental cues.
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Affiliation(s)
- Alisa Boucsein
- Centre for Neuroendocrinology, Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Kaj Kamstra
- Centre for Neuroendocrinology, Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Alexander Tups
- Centre for Neuroendocrinology, Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
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18
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Yoshida R, Margolskee RF, Ninomiya Y. Phosphatidylinositol-3 kinase mediates the sweet suppressive effect of leptin in mouse taste cells. J Neurochem 2021; 158:233-245. [PMID: 33319361 DOI: 10.1111/jnc.15268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 12/20/2022]
Abstract
Leptin is known to selectively suppress neural and taste cell responses to sweet compounds. The sweet suppressive effect of leptin is mediated by the leptin receptor Ob-Rb, and the ATP-gated K+ (KATP ) channel expressed in some sweet-sensitive, taste receptor family 1 member 3 (T1R3)-positive taste cells. However, the intracellular transduction pathway connecting Ob-Rb to KATP channel remains unknown. Here we report that phosphoinositide 3-kinase (PI3K) mediates leptin's suppression of sweet responses in T1R3-positive taste cells. In in situ taste cell recording, systemically administrated leptin suppressed taste cell responses to sucrose in T1R3-positive taste cells. Such leptin's suppression of sucrose responses was impaired by co-administration of PI3K inhibitors (wortmannin or LY294002). In contrast, co-administration of signal transducer and activator of transcription 3 inhibitor (Stattic) or Src homology region 2 domain-containing phosphatase-2 inhibitor (SHP099) had no effect on leptin's suppression of sucrose responses, although signal transducer and activator of transcription 3 and Src homology region 2 domain-containing phosphatase-2 were expressed in T1R3-positive taste cells. In peeled tongue epithelium, phosphatidylinositol (3,4,5)-trisphosphate production and phosphorylation of AKT by leptin were immunohistochemically detected in some T1R3-positive taste cells but not in glutamate decarboxylase 67-positive taste cells. Leptin-induced phosphatidylinositol (3,4,5)-trisphosphate production was suppressed by LY294002. Thus, leptin suppresses sweet responses of T1R3-positive taste cells by activation of Ob-Rb-PI3K-KATP channel pathway.
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Affiliation(s)
- Ryusuke Yoshida
- Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | | | - Yuzo Ninomiya
- Monell Chemical Senses Center, Philadelphia, PA, USA.,Oral Science Research Center, Tokyo Dental College, Tokyo, Japan.,Division of Sensory Physiology, Research and Development Center for Five-Sense Device, Kyushu University, Fukuoka, Japan
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19
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Anjum S, Khattak MNK, Tsutsui K, Krishna A. RF-amide related peptide-3 (RFRP-3): a novel neuroendocrine regulator of energy homeostasis, metabolism, and reproduction. Mol Biol Rep 2021; 48:1837-1852. [PMID: 33566226 DOI: 10.1007/s11033-021-06198-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 01/28/2021] [Indexed: 11/29/2022]
Abstract
A hypothalamic neuropeptide, RF-amide related peptide-3 (RFRP-3), the mammalian ortholog of the avian gonadotropin-inhibitory hormone (GnIH) has inhibitory signals for reproductive axis via G-protein coupled receptor 147 in mammals. Moreover, RFRP-3 has orexigenic action but the mechanism involved in energy homeostasis and glucose metabolism is not yet known. Though, the RFRP-3 modulates orexigenic action in co-operation with other neuropeptides, which regulates metabolic cues in the hypothalamus. Administration of GnIH/RFRP-3 suppresses plasma luteinizing hormone, at the same time stimulates feeding behavior in birds and mammals. Likewise, in the metabolically deficient conditions, its expression is up-regulated suggests that RFRP-3 contributes to the integration of energy balance and reproduction. However, in many other metabolic conditions like induced diabetes and high-fat diet obesity, etc. its role is still not clear while, RFRP-3 induces the glucose homeostasis by adipocytes is reported. The physiological role of RFRP-3 in metabolic homeostasis and the metabolic effects of RFRP-3 signaling in pharmacological studies need a detailed discussion. Further studies are required to find out whether RFRP-3 is associated with restricted neuroendocrine function observed in type II diabetes mellitus, aging, or sub-fertility. In this context, the current review is focused on the role of RFRP-3 in the above-mentioned mechanisms. Studies from search engines including PubMed, Google Scholar, and science.gov are included after following set inclusion/exclusion criteria. As a developing field few mechanisms are still inconclusive, however, based on the available information RFRP-3 seems to be a putative tool in future treatment strategies towards metabolic disease.
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Affiliation(s)
- Shabana Anjum
- Department of Zoology, Banaras Hindu University, Varanasi, Uttar Pradesh, India
- Sharjah Institute of Medical Research, University of Sharjah, Sharjah, United Arab Emirates
| | | | - Kazuyoshi Tsutsui
- Graduate School of Integrated Sciences for Life, Hiroshima University, Kagamiyama 1-7-1, Higashi-Hiroshima, 739-8521, Japan
| | - Amitabh Krishna
- Department of Zoology, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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20
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Abstract
A healthy nutritional state is required for all aspects of reproduction and is signaled by the adipokine leptin. Leptin acts in a relatively narrow concentration range: too much or too little will compromise fertility. The leptin signal timing is important to prepubertal development in both sexes. In the brain, leptin acts on ventral premammillary neurons which signal kisspeptin (Kiss1) neurons to stimulate gonadotropin releasing hormone (GnRH) neurons. Suppression of Kiss1 neurons occurs when agouti-related peptide neurons are activated by reduced leptin, because leptin normally suppresses these orexigenic neurons. In the pituitary, leptin stimulates production of GnRH receptors (GnRHRs) and follicle-stimulating hormone at midcycle, by activating pathways that derepress actions of the messenger ribonucleic acid translational regulatory protein Musashi. In females, rising estrogen stimulates a rise in serum leptin, which peaks at midcycle, synchronizing with nocturnal luteinizing hormone pulses. The normal range of serum leptin levels (10-20 ng/mL) along with gonadotropins and growth factors promote ovarian granulosa and theca cell functions and oocyte maturation. In males, the prepubertal rise in leptin promotes testicular development. However, a decline in leptin levels in prepubertal boys reflects inhibition of leptin secretion by rising androgens. In adult males, leptin levels are 10% to 50% of those in females, and high leptin inhibits testicular function. The obesity epidemic has elucidated leptin resistance pathways, with too much leptin in either sex leading to infertility. Under conditions of balanced nutrition, however, the secretion of leptin is timed and regulated within a narrow level range that optimizes its trophic effects.
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Affiliation(s)
- Gwen V Childs
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Correspondence: Gwen V. Childs, PhD, University of Arkansas for Medical Sciences, Little Rock, AR, USA. E-mail:
| | - Angela K Odle
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Melanie C MacNicol
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Angus M MacNicol
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas
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21
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Regulation of Postabsorptive and Postprandial Glucose Metabolism by Insulin-Dependent and Insulin-Independent Mechanisms: An Integrative Approach. Nutrients 2021; 13:nu13010159. [PMID: 33419065 PMCID: PMC7825450 DOI: 10.3390/nu13010159] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/18/2020] [Accepted: 12/24/2020] [Indexed: 12/18/2022] Open
Abstract
Glucose levels in blood must be constantly maintained within a tight physiological range to sustain anabolism. Insulin regulates glucose homeostasis via its effects on glucose production from the liver and kidneys and glucose disposal in peripheral tissues (mainly skeletal muscle). Blood levels of glucose are regulated simultaneously by insulin-mediated rates of glucose production from the liver (and kidneys) and removal from muscle; adipose tissue is a key partner in this scenario, providing nonesterified fatty acids (NEFA) as an alternative fuel for skeletal muscle and liver when blood glucose levels are depleted. During sleep at night, the gradual development of insulin resistance, due to growth hormone and cortisol surges, ensures that blood glucose levels will be maintained within normal levels by: (a) switching from glucose to NEFA oxidation in muscle; (b) modulating glucose production from the liver/kidneys. After meals, several mechanisms (sequence/composition of meals, gastric emptying/intestinal glucose absorption, gastrointestinal hormones, hyperglycemia mass action effects, insulin/glucagon secretion/action, de novo lipogenesis and glucose disposal) operate in concert for optimal regulation of postprandial glucose fluctuations. The contribution of the liver in postprandial glucose homeostasis is critical. The liver is preferentially used to dispose over 50% of the ingested glucose and restrict the acute increases of glucose and insulin in the bloodstream after meals, thus protecting the circulation and tissues from the adverse effects of marked hyperglycemia and hyperinsulinemia.
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22
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Bédécarrats GY, Hanlon C, Tsutsui K. Gonadotropin Inhibitory Hormone and Its Receptor: Potential Key to the Integration and Coordination of Metabolic Status and Reproduction. Front Endocrinol (Lausanne) 2021; 12:781543. [PMID: 35095760 PMCID: PMC8792613 DOI: 10.3389/fendo.2021.781543] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/02/2021] [Indexed: 12/18/2022] Open
Abstract
Since its discovery as a novel gonadotropin inhibitory peptide in 2000, the central and peripheral roles played by gonadotropin-inhibiting hormone (GnIH) have been significantly expanded. This is highlighted by the wide distribution of its receptor (GnIH-R) within the brain and throughout multiple peripheral organs and tissues. Furthermore, as GnIH is part of the wider RF-amide peptides family, many orthologues have been characterized across vertebrate species, and due to the promiscuity between ligands and receptors within this family, confusion over the nomenclature and function has arisen. In this review, we intend to first clarify the nomenclature, prevalence, and distribution of the GnIH-Rs, and by reviewing specific localization and ligand availability, we propose an integrative role for GnIH in the coordination of reproductive and metabolic processes. Specifically, we propose that GnIH participates in the central regulation of feed intake while modulating the impact of thyroid hormones and the stress axis to allow active reproduction to proceed depending on the availability of resources. Furthermore, beyond the central nervous system, we also propose a peripheral role for GnIH in the control of glucose and lipid metabolism at the level of the liver, pancreas, and adipose tissue. Taken together, evidence from the literature strongly suggests that, in fact, the inhibitory effect of GnIH on the reproductive axis is based on the integration of environmental cues and internal metabolic status.
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Affiliation(s)
- Grégoy Y. Bédécarrats
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
- *Correspondence: Grégoy Y. Bédécarrats,
| | - Charlene Hanlon
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Kazuyoshi Tsutsui
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
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23
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Giri B, Dey S, Murmu N, Bose M, Ghosh S. Obesity and chronic leptin resistance foster insulin resistance: An analytical overview. BLDE UNIVERSITY JOURNAL OF HEALTH SCIENCES 2021. [DOI: 10.4103/bjhs.bjhs_29_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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24
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Liu M, Shen L, Xu M, Wang DQH, Tso P. Estradiol Enhances Anorectic Effect of Apolipoprotein A-IV through ERα-PI3K Pathway in the Nucleus Tractus Solitarius. Genes (Basel) 2020; 11:E1494. [PMID: 33322656 PMCID: PMC7764025 DOI: 10.3390/genes11121494] [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: 09/21/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 01/09/2023] Open
Abstract
Estradiol (E2) enhances the anorectic action of apolipoprotein A-IV (apoA-IV), however, the intracellular mechanisms are largely unclear. Here we reported that the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway was significantly activated by E2 and apoA-IV, respectively, in primary neuronal cells isolated from rat embryonic brainstem. Importantly, the combination of E2 and apoA-IV at their subthreshold doses synergistically activated the PI3K/Akt signaling pathway. These effects, however, were significantly diminished by the pretreatment with LY294002, a selective PI3K inhibitor. E2-induced activation of the PI3K/Akt pathway was through membrane-associated ERα, because the phosphorylation of Akt was significantly increased by PPT, an ERα agonist, and by E2-BSA (E2 conjugated to bovine serum albumin) which activates estrogen receptor on the membrane. Centrally administered apoA-IV at a low dose (0.5 µg) significantly suppressed food intake and increased the phosphorylation of Akt in the nucleus tractus solitarius (NTS) of ovariectomized (OVX) rats treated with E2, but not in OVX rats treated with vehicle. These effects were blunted by pretreatment with LY294002. These results indicate that E2's regulatory role in apoA-IV's anorectic action is through the ERα-PI3K pathway in the NTS. Manipulation of the PI3K/Akt signaling activation in the NTS may provide a novel therapeutic approach for the prevention and the treatment of obesity-related disorders in females.
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Affiliation(s)
- Min Liu
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA; (L.S.); (M.X.); (P.T.)
| | - Ling Shen
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA; (L.S.); (M.X.); (P.T.)
| | - Meifeng Xu
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA; (L.S.); (M.X.); (P.T.)
| | - David Q.-H. Wang
- Department of Medicine and Genetics, Division of Gastroenterology and Liver Diseases, Marion Bessin Liver Research Center, Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Patrick Tso
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA; (L.S.); (M.X.); (P.T.)
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25
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Sun Q, Liu Y, Wei W, Wu D, Lin R, Wen D, Jia L. Chronic Timed Sleep Restriction Attenuates LepRb-Mediated Signaling Pathways and Circadian Clock Gene Expression in the Rat Hypothalamus. Front Neurosci 2020; 14:909. [PMID: 33013300 PMCID: PMC7507490 DOI: 10.3389/fnins.2020.00909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022] Open
Abstract
The sleep duration of adolescents has continued to decline over the past 20 years. Sleep insufficiency is one of the most important risk factors for obesity, but the mechanisms underlying the association are unclear. Therefore, the hypothalamic-regulated mechanisms of appetite and the circadian clock gene expression were examined in sleep-restricted rats. Rats aged 7 weeks were randomly divided into two groups: the control group and sleep restriction group (7 rats/group) rats were sleep-restricted for 4 weeks. Body weight gain and amount of food/water consumption were quantified. The expression of genes or proteins which regulated appetite and energy metabolism via leptin receptor signaling and the circadian clock in the hypothalamus were assessed. Chronic sleep restriction induced increased food intake and weight gain in adolescent and young adult rats from the second week of initiation of sleep restriction. Phosphorylation of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) was decreased, although levels of circulating leptin or leptin receptor expression were unaltered. Furthermore, insulin receptor substrate (IRS)/phosphoinositide 3-kinase (PI3K)/AKT/mTOR and forkhead box O1 (FoxO1) signaling pathways were also compromised. Moreover, core circadian clock genes were also decreased in the sleep restriction group compared with the control. Chronic timed sleep restriction induced hyperphagic behaviors, attenuated leptin receptor-mediated signaling pathways, and depleted the expression of circadian clock gene in the hypothalamus of adolescent and young adult rats.
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Affiliation(s)
- Qi Sun
- Department of Child and Adolescent Health, School of Public Health, China Medical University, Shenyang, China
| | - Yang Liu
- Institute of Health Science, China Medical University, Shenyang, China
| | - Wei Wei
- Department of Child and Adolescent Health, School of Public Health, China Medical University, Shenyang, China
| | - Dan Wu
- Department of Child and Adolescent Health, School of Public Health, China Medical University, Shenyang, China
| | - Ren Lin
- Department of Child and Adolescent Health, School of Public Health, China Medical University, Shenyang, China
| | - Deliang Wen
- Institute of Health Science, China Medical University, Shenyang, China
| | - Lihong Jia
- Department of Child and Adolescent Health, School of Public Health, China Medical University, Shenyang, China
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Sergi D, Williams LM. Potential relationship between dietary long-chain saturated fatty acids and hypothalamic dysfunction in obesity. Nutr Rev 2020; 78:261-277. [PMID: 31532491 DOI: 10.1093/nutrit/nuz056] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Diet-induced hypothalamic inflammation, which leads to hypothalamic dysfunction and a loss of regulation of energy balance, is emerging as a potential driver of obesity. Excessive intake of long-chain saturated fatty acids is held to be the causative dietary component in hypothalamic inflammation. This review summarizes current evidence on the role of long-chain saturated fatty acids in promoting hypothalamic inflammation and the related induction of central insulin and leptin insensitivity. Particularly, the present review focuses on the molecular mechanisms linking long-chain saturated fatty acids and hypothalamic inflammation, emphasizing the metabolic fate of fatty acids and the resulting lipotoxicity, which is a key driver of hypothalamic dysfunction. In conclusion, long-chain saturated fatty acids are key nutrients that promote hypothalamic inflammation and dysfunction by fostering the build-up of lipotoxic lipid species, such as ceramide. Furthermore, when long-chain saturated fatty acids are consumed in combination with high levels of refined carbohydrates, the proinflammatory effects are exacerbated via a mechanism that relies on the formation of advanced glycation end products.
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Affiliation(s)
- Domenico Sergi
- Nutrition and Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, South Australia, Australia
| | - Lynda M Williams
- Rowett Institute, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
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Roles of Gangliosides in Hypothalamic Control of Energy Balance: New Insights. Int J Mol Sci 2020; 21:ijms21155349. [PMID: 32731387 PMCID: PMC7432706 DOI: 10.3390/ijms21155349] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/20/2020] [Accepted: 07/26/2020] [Indexed: 12/19/2022] Open
Abstract
Gangliosides are essential components of cell membranes and are involved in a variety of physiological processes, including cell growth, differentiation, and receptor-mediated signal transduction. They regulate functions of proteins in membrane microdomains, notably receptor tyrosine kinases such as insulin receptor (InsR) and epidermal growth factor receptor (EGFR), through lateral association. Studies during the past two decades using knockout (KO) or pharmacologically inhibited cells, or KO mouse models for glucosylceramide synthase (GCS; Ugcg), GM3 synthase (GM3S; St3gal5), and GD3 synthase (GD3S; St8sia1) have revealed essential roles of gangliosides in hypothalamic control of energy balance. The a-series gangliosides GM1 and GD1a interact with leptin receptor (LepR) and promote LepR signaling through activation of the JAK2/STAT3 pathway. Studies of GM3S KO cells have shown that the extracellular signal-regulated kinase (ERK) pathway, downstream of the LepR signaling pathway, is also modulated by gangliosides. Recent studies have revealed crosstalk between the LepR signaling pathway and other receptor signaling pathways (e.g., InsR and EGFR pathways). Gangliosides thus have the ability to modulate the effects of leptin by regulating functions of such receptors, and by direct interaction with LepR to control signaling.
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Flees J, Greene E, Ganguly B, Dridi S. Phytogenic feed- and water-additives improve feed efficiency in broilers via modulation of (an)orexigenic hypothalamic neuropeptide expression. Neuropeptides 2020; 81:102005. [PMID: 31926603 DOI: 10.1016/j.npep.2020.102005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/17/2019] [Accepted: 01/02/2020] [Indexed: 12/12/2022]
Abstract
Fueled by consumer preference for natural and antibiotic-free products, phytogenics have become the fastest growing segment of the animal feed additives. Yet, their modes of action are not fully understood. This study was undertaken to determine the effect of 5 phytogenics (3 feed- and 2 water-supplements) on the growth performance of commercial broilers, and their potential underlying molecular mechanisms. Day-old male Cobb 500 chicks (n = 576) were randomly assigned into 48 pens consisting of 6 treatments (Control; AVHGP; SCP; BHGP; AVSSL; SG) in a complete randomized design (12 birds/pen, 8 pens/treatment, 96 birds/treatment). Chicks had ad libitum access to feed and water. Individual body weight (BW) was recorded weekly and feed intake was measured daily. Core body temperatures were continuously recorded using thermo-loggers. At d 35, hypothalamic tissues were excised from the thermo-logger-equipped chickens (n = 8 birds/treatment) to determine the expression of feeding-related neuropeptides. Both feed (AVHGP, SCP, BHGP) and water-supplemented (AVSSL, SG) phytogenics significantly improved feed efficiency (FE) compared to the control birds. This higher FE was achieved via a reduction in core body temperature and improvement of market BW, without changes in feed intake in broilers supplemented with phytogenic water additives as compared to the control group. Broilers fed dietary phytogenics, however, attained higher feed efficiency via a reduction in feed intake while maintaining similar BW as the control group. At the molecular levels, the effects of the phytogenic water additives seemed to be mediated by the activation of the hypothalamic AgRP-ORX-mTOR-S6k1 and inhibition of CRH pathways. The effect of the phytogenic feed additives appeared to be exerted through the activation of AdipoQ, STAT3, AMPK, and MC1R pathways. This is the first report describing the likely central mechanisms through which phytogenic additives improve the growth performance and feed efficiency in broilers.
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Affiliation(s)
- Joshua Flees
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, United States of America
| | - Elizabeth Greene
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, United States of America
| | - Bhaskar Ganguly
- Clinical Research, Ayurvet Limited, Baddi, Himachal Pradesh 173205, India
| | - Sami Dridi
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, United States of America.
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Sudhakar SR, Pathak H, Rehman N, Fernandes J, Vishnu S, Varghese J. Insulin signalling elicits hunger-induced feeding in Drosophila. Dev Biol 2020; 459:87-99. [DOI: 10.1016/j.ydbio.2019.11.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 11/18/2019] [Accepted: 11/20/2019] [Indexed: 12/21/2022]
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Boyle CN, Le Foll C. Amylin and Leptin interaction: Role During Pregnancy, Lactation and Neonatal Development. Neuroscience 2019; 447:136-147. [PMID: 31846753 DOI: 10.1016/j.neuroscience.2019.11.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Revised: 11/08/2019] [Accepted: 11/21/2019] [Indexed: 01/04/2023]
Abstract
Amylin is co-secreted with insulin by pancreatic β-cells in response to a meal and produced by neurons in discrete hypothalamic brain areas. Leptin is proportionally secreted by the adipose tissue. Both hormones control food intake and energy homeostasis post-weaning in rodents. While amylin's main site of action is located in the area postrema (AP) and leptin's is located in the mediobasal hypothalamus, both hormones can also influence the other's signaling pathway; amylin has been shown enhance hypothalamic leptin signaling, and amylin signaling in the AP may rely on functional leptin receptors to modulate its effects. These two hormones also play major roles during other life periods. During pregnancy, leptin levels rise as a result of an increase in fat depot resulting in gestational leptin-resistance to prepare the maternal body for the metabolic needs during fetal development. The role of amylin is far less studied during pregnancy and lactation, though amylin levels seem to be elevated during pregnancy relative to insulin. Whether amylin and leptin interact during pregnancy and lactation remains to be assessed. Lastly, during brain development, amylin and leptin are major regulators of cell birth during embryogenesis and act as neurotrophic factors in the neonatal period. This review will highlight the role of amylin and leptin, and their possible interaction, during these dynamic time periods of pregnancy, lactation, and early development.
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Affiliation(s)
- Christina N Boyle
- Institute of Veterinary Physiology, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
| | - Christelle Le Foll
- Institute of Veterinary Physiology, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
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31
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Lin Y, Yang Z, Lake RJ, Zheng C, Lu Y. Enzyme‐Mediated Endogenous and Bioorthogonal Control of a DNAzyme Fluorescent Sensor for Imaging Metal Ions in Living Cells. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201910343] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yao Lin
- Department of ChemistryDepartment of BiochemistryUniversity of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
- Key Laboratory of Green Chemistry & TechnologyMinistry of EducationCollege of ChemistrySichuan University Chengdu Sichuan 610064 China
| | - Zhenglin Yang
- Department of ChemistryDepartment of BiochemistryUniversity of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Ryan J. Lake
- Department of ChemistryDepartment of BiochemistryUniversity of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Chengbin Zheng
- Key Laboratory of Green Chemistry & TechnologyMinistry of EducationCollege of ChemistrySichuan University Chengdu Sichuan 610064 China
| | - Yi Lu
- Department of ChemistryDepartment of BiochemistryUniversity of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
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32
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Lin Y, Yang Z, Lake RJ, Zheng C, Lu Y. Enzyme-Mediated Endogenous and Bioorthogonal Control of a DNAzyme Fluorescent Sensor for Imaging Metal Ions in Living Cells. Angew Chem Int Ed Engl 2019; 58:17061-17067. [PMID: 31529664 PMCID: PMC7174831 DOI: 10.1002/anie.201910343] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/12/2019] [Indexed: 11/09/2022]
Abstract
Bioorthogonal control of metal-ion sensors for imaging metal ions in living cells is important for understanding the distribution and fluctuation of metal ions. Reported here is the endogenous and bioorthogonal activation of a DNAzyme fluorescent sensor containing an 18-base pair recognition site of a homing endonuclease (I-SceI), which is found by chance only once in 7×1010 bp of genomic sequences, and can thus form a near bioorthogonal pair with I-SceI for DNAzyme activation with minimal effect on living cells. Once I-SceI is expressed inside cells, it cleaves at the recognition site, allowing the DNAzyme to adopt its active conformation. The activated DNAzyme sensor is then able to specifically catalyze cleavage of a substrate strand in the presence of Mg2+ to release the fluorophore-labeled DNA fragment and produce a fluorescent turn-on signal for Mg2+ . Thus I-SceI bioorthogonally activates the 10-23 DNAzyme for imaging of Mg2+ in HeLa cells.
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Affiliation(s)
- Yao Lin
- Department of Chemistry, Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Zhenglin Yang
- Department of Chemistry, Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Ryan J. Lake
- Department of Chemistry, Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Chengbin Zheng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Yi Lu
- Department of Chemistry, Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
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Rivadeneira DB, DePeaux K, Wang Y, Kulkarni A, Tabib T, Menk AV, Sampath P, Lafyatis R, Ferris RL, Sarkar SN, Thorne SH, Delgoffe GM. Oncolytic Viruses Engineered to Enforce Leptin Expression Reprogram Tumor-Infiltrating T Cell Metabolism and Promote Tumor Clearance. Immunity 2019; 51:548-560.e4. [PMID: 31471106 DOI: 10.1016/j.immuni.2019.07.003] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 05/16/2019] [Accepted: 07/12/2019] [Indexed: 02/07/2023]
Abstract
Immunotherapy can reinvigorate dormant responses to cancer, but response rates remain low. Oncolytic viruses, which replicate in cancer cells, induce tumor lysis and immune priming, but their immune consequences are unclear. We profiled the infiltrate of aggressive melanomas induced by oncolytic Vaccinia virus using RNA sequencing and found substantial remodeling of the tumor microenvironment, dominated by effector T cell influx. However, responses to oncolytic viruses were incomplete due to metabolic insufficiencies induced by the tumor microenvironment. We identified the adipokine leptin as a potent metabolic reprogramming agent that supported antitumor responses. Leptin metabolically reprogrammed T cells in vitro, and melanoma cells expressing leptin were immunologically controlled in mice. Engineering oncolytic viruses to express leptin in tumor cells induced complete responses in tumor-bearing mice and supported memory development in the tumor infiltrate. Thus, leptin can provide metabolic support to tumor immunity, and oncolytic viruses represent a platform to deliver metabolic therapy.
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Affiliation(s)
- Dayana B Rivadeneira
- Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kristin DePeaux
- Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yiyang Wang
- Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA; School of Medicine, Tsinghua University, Beijing, China
| | - Aditi Kulkarni
- Head and Neck Cancer SPORE, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tracy Tabib
- Division of Rheumatology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Ashley V Menk
- Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Robert Lafyatis
- Division of Rheumatology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Robert L Ferris
- Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA; Head and Neck Cancer SPORE, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Stephen H Thorne
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Greg M Delgoffe
- Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA; Head and Neck Cancer SPORE, University of Pittsburgh, Pittsburgh, PA, USA.
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Buchanan CM, Lee KL, Shepherd PR. For Better or Worse: The Potential for Dose Limiting the On-Target Toxicity of PI 3-Kinase Inhibitors. Biomolecules 2019; 9:biom9090402. [PMID: 31443495 PMCID: PMC6770514 DOI: 10.3390/biom9090402] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/15/2019] [Accepted: 08/21/2019] [Indexed: 02/07/2023] Open
Abstract
The hyper-activation of the phosphoinositide (PI) 3-kinase signaling pathway is a hallmark of many cancers and overgrowth syndromes, and as a result, there has been intense interest in the development of drugs that target the various isoforms of PI 3-kinase. Given the key role PI 3-kinases play in many normal cell functions, there is significant potential for the disruption of essential cellular functions by PI 3-kinase inhibitors in normal tissues; so-called on-target drug toxicity. It is, therefore, no surprise that progress within the clinical development of PI 3-kinase inhibitors as single-agent anti-cancer therapies has been slowed by the difficulty of identifying a therapeutic window. The aim of this review is to place the cellular, tissue and whole-body effects of PI 3-kinase inhibition in the context of understanding the potential for dose limiting on-target toxicities and to introduce possible strategies to overcome these.
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Affiliation(s)
- Christina M Buchanan
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Kate L Lee
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
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35
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Inagaki-Ohara K. Gastric Leptin and Tumorigenesis: Beyond Obesity. Int J Mol Sci 2019; 20:ijms20112622. [PMID: 31141984 PMCID: PMC6600422 DOI: 10.3390/ijms20112622] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 05/24/2019] [Accepted: 05/24/2019] [Indexed: 12/13/2022] Open
Abstract
Leptin, an adipocyte-derived hormone and its receptor (ObR) expressed in the hypothalamus are well known as an essential regulator of appetite and energy expenditure. Obesity induces abundant leptin production, however, reduced sensitivity to leptin leads to the development of metabolic disorders, so called leptin resistance. The stomach has been identified as an organ that simultaneously expresses leptin and ObR. Accumulating evidence has shown gastric leptin to perform diverse functions, such as those in nutrient absorption and carcinogenesis in the gastrointestinal system, independent of its well-known role in appetite regulation and obesity. Overexpression of leptin and phosphorylated ObR is implicated in gastric cancer in humans and in murine model, and diet-induced obesity causes precancerous lesions in the stomach in mice. While the underlying pathomechanisms remain unclear, leptin signaling can affect gastric mucosal milieu. In this review, we focus on the significant role of the gastric leptin signaling in neoplasia and tumorigenesis in stomach in the context of hereditary and diet-induced obesity.
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Affiliation(s)
- Kyoko Inagaki-Ohara
- Division of Host Defense, Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 5562 Nanatsuka, Shobara, Hiroshima 727-0023, Japan.
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Cai R, Tang G, Zhang Q, Yong W, Zhang W, Xiao J, Wei C, He C, Yang G, Pang W. A Novel lnc-RNA, Named lnc-ORA, Is Identified by RNA-Seq Analysis, and Its Knockdown Inhibits Adipogenesis by Regulating the PI3K/AKT/mTOR Signaling Pathway. Cells 2019; 8:cells8050477. [PMID: 31109074 PMCID: PMC6562744 DOI: 10.3390/cells8050477] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/16/2019] [Accepted: 05/16/2019] [Indexed: 12/17/2022] Open
Abstract
Obesity is closely associated with numerous adipogenic regulatory factors, including coding and non-coding genes. Long noncoding RNAs (lncRNAs) play a major role in adipogenesis. However, differential expression profiles of lncRNAs in inguinal white adipose tissue (iWAT) between wild-type (WT) and ob/ob mice, as well as their roles in adipogenesis, are not well understood. Here, a total of 2809 lncRNAs were detected in the iWAT of WT and ob/ob mice by RNA-Sequencing (RNA-Seq), including 248 novel lncRNAs. Of them, 46 lncRNAs were expressed differentially in WT and ob/ob mice and were enriched in adipogenesis signaling pathways as determined by KEGG enrichment analysis, including the PI3K/AKT/mTOR and cytokine-cytokine receptor interaction signaling pathways. Furthermore, we focused on one novel lncRNA, which we named lnc-ORA (obesity-related lncRNA), which had a seven-fold higher expression in ob/ob mice than in WT mice. Knockdown of lnc-ORA inhibited preadipocyte proliferation by decreasing the mRNA and protein expression levels of cell cycle markers. Interestingly, lnc-ORA knockdown inhibited adipocyte differentiation by regulating the PI3K/AKT/mTOR signaling pathway. In summary, these findings contribute to a better understanding of adipogenesis in relation to lncRNAs and provide novel potential therapeutic targets for obesity-related metabolic diseases.
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Affiliation(s)
- Rui Cai
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Guorong Tang
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Que Zhang
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Wenlong Yong
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Wanrong Zhang
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Junying Xiao
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Changsheng Wei
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Chun He
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Gongshe Yang
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Weijun Pang
- Laboratory of Animal Fat Deposition and Muscle Development, Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China.
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Garcia-Galiano D, Borges BC, Allen SJ, Elias CF. PI3K signalling in leptin receptor cells: Role in growth and reproduction. J Neuroendocrinol 2019; 31:e12685. [PMID: 30618188 PMCID: PMC6533139 DOI: 10.1111/jne.12685] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/04/2019] [Accepted: 01/04/2019] [Indexed: 12/15/2022]
Abstract
Nutrition and growth are important signals for pubertal development, although how they are perceived and integrated in brain circuits has not been well defined. Growth hormones and metabolic cues both recruit phosphatidylinositol 3-kinase (PI3K) signalling in hypothalamic sites, although whether they converge into the same neuronal population(s) is also not known. In this review, we discuss recent findings from our laboratory showing the role of PI3K subunits in cells directly responsive to the adipocyte-derived hormone leptin in the coordination of growth, pubertal development and fertility. Mice with deletion of PI3K p110α and p110β catalytic subunits in leptin receptor cells (LRΔα+β ) have a lean phenotype associated with increased energy expenditure, locomotor activity and thermogenesis. The LRΔα+β mice also show deficient growth and delayed puberty. Deletion of a single subunit (ie, p110α) in LR cells (LRΔα ) causes a similar phenotype of increased energy expenditure, deficient growth and delayed pubertal development, indicating that these functions are preferably controlled by p110α. The LRΔα mice show enhanced leptin sensitivity in metabolic regulation but, remarkably, these mice are unresponsive to the effects of leptin on growth and puberty. PI3K is also recruited by insulin and a subpopulation of LR neurones is responsive to i.c.v. insulin administration. Deletion of insulin receptor in LR cells causes no changes in body weight or linear growth and induces only a mild delay in pubertal completion. Our findings demonstrate that PI3K in LR cells plays an essential role in growth and reproduction. We will also discuss the potential neural pathways underlying these effects.
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Affiliation(s)
- David Garcia-Galiano
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Beatriz C. Borges
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Kresge Hearing Research Institute and Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Susan J. Allen
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Carol F. Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA
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Suarez AN, Noble EE, Kanoski SE. Regulation of Memory Function by Feeding-Relevant Biological Systems: Following the Breadcrumbs to the Hippocampus. Front Mol Neurosci 2019; 12:101. [PMID: 31057368 PMCID: PMC6482164 DOI: 10.3389/fnmol.2019.00101] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 04/03/2019] [Indexed: 12/15/2022] Open
Abstract
The hippocampus (HPC) controls fundamental learning and memory processes, including memory for visuospatial navigation (spatial memory) and flexible memory for facts and autobiographical events (declarative memory). Emerging evidence reveals that hippocampal-dependent memory function is regulated by various peripheral biological systems that are traditionally known for their roles in appetite and body weight regulation. Here, we argue that these effects are consistent with a framework that it is evolutionarily advantageous to encode and recall critical features surrounding feeding behavior, including the spatial location of a food source, social factors, post-absorptive processing, and other episodic elements of a meal. We review evidence that gut-to-brain communication from the vagus nerve and from feeding-relevant endocrine systems, including ghrelin, insulin, leptin, and glucagon-like peptide-1 (GLP-1), promote hippocampal-dependent spatial and declarative memory via neurotrophic and neurogenic mechanisms. The collective literature reviewed herein supports a model in which various stages of feeding behavior and hippocampal-dependent memory function are closely linked.
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Affiliation(s)
- Andrea N Suarez
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
| | - Emily E Noble
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
| | - Scott E Kanoski
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
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Qu J, Ko CW, Tso P, Bhargava A. Apolipoprotein A-IV: A Multifunctional Protein Involved in Protection against Atherosclerosis and Diabetes. Cells 2019; 8:E319. [PMID: 30959835 PMCID: PMC6523623 DOI: 10.3390/cells8040319] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 03/31/2019] [Accepted: 04/02/2019] [Indexed: 12/19/2022] Open
Abstract
Apolipoprotein A-IV (apoA-IV) is a lipid-binding protein, which is primarily synthesized in the small intestine, packaged into chylomicrons, and secreted into intestinal lymph during fat absorption. In the circulation, apoA-IV is present on chylomicron remnants, high-density lipoproteins, and also in lipid-free form. ApoA-IV is involved in a myriad of physiological processes such as lipid absorption and metabolism, anti-atherosclerosis, platelet aggregation and thrombosis, glucose homeostasis, and food intake. ApoA-IV deficiency is associated with atherosclerosis and diabetes, which renders it as a potential therapeutic target for treatment of these diseases. While much has been learned about the physiological functions of apoA-IV using rodent models, the action of apoA-IV at the cellular and molecular levels is less understood, let alone apoA-IV-interacting partners. In this review, we will summarize the findings on the molecular function of apoA-IV and apoA-IV-interacting proteins. The information will shed light on the discovery of apoA-IV receptors and the understanding of the molecular mechanism underlying its mode of action.
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Affiliation(s)
- Jie Qu
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati, 2180 E Galbraith Road, Cincinnati, OH 45237-0507, USA.
| | - Chih-Wei Ko
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati, 2180 E Galbraith Road, Cincinnati, OH 45237-0507, USA.
| | - Patrick Tso
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati, 2180 E Galbraith Road, Cincinnati, OH 45237-0507, USA.
| | - Aditi Bhargava
- Department of Obstetrics, Gynecology & Reproductive Sciences, University of California, 513 Parnassus Avenue, San Francisco, CA 94143-0556, USA.
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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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Papathanasiou AE, Nolen-Doerr E, Farr OM, Mantzoros CS. GEOFFREY HARRIS PRIZE LECTURE 2018: Novel pathways regulating neuroendocrine function, energy homeostasis and metabolism in humans. Eur J Endocrinol 2019; 180:R59-R71. [PMID: 30475221 PMCID: PMC6378110 DOI: 10.1530/eje-18-0847] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 11/05/2018] [Indexed: 12/12/2022]
Abstract
The discovery of leptin, an adipocyte-secreted hormone, set the stage for unraveling the mechanisms dictating energy homeostasis, revealing adipose tissue as an endocrine system that regulates appetite and body weight. Fluctuating leptin levels provide molecular signals to the brain regarding available energy reserves modulating energy homeostasis and neuroendocrine response in states of leptin deficiency and to a lesser extent in hyperleptinemic states. While leptin replacement therapy fails to provide substantial benefit in common obesity, it is an effective treatment for congenital leptin deficiency and states of acquired leptin deficiency such as lipodystrophy. Current evidence suggests that regulation of eating behavior in humans is not limited to homeostatic mechanisms and that the reward, attention, memory and emotion systems are involved, participating in a complex central nervous system network. It is critical to study these systems for the treatment of typical obesity. Although progress has been made, further studies are required to unravel the physiology, pathophysiology and neurobehavioral mechanisms underlying potential treatments for weight-related problems in humans.
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Affiliation(s)
| | - Eric Nolen-Doerr
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215
| | - Olivia M. Farr
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215
| | - Christos S. Mantzoros
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215
- Address correspondence to: Christos Mantzoros, MD, DSc, PhD h.c. mult., Beth Israel Deaconess Medical Center, 330 Brookline Ave, ST820, Boston, MA 02215, Phone: 617-667-1510,
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Pan W, Allison MB, Sabatini P, Rupp A, Adams J, Patterson C, Jones JC, Olson DP, Myers MG. Transcriptional and physiological roles for STAT proteins in leptin action. Mol Metab 2019; 22:121-131. [PMID: 30718218 PMCID: PMC6437596 DOI: 10.1016/j.molmet.2019.01.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/14/2019] [Accepted: 01/17/2019] [Indexed: 12/26/2022] Open
Abstract
Objectives Leptin acts via its receptor LepRb on specialized neurons in the brain to modulate food intake, energy expenditure, and body weight. LepRb activates signal transducers and activators of transcription (STATs, including STAT1, STAT3, and STAT5) to control gene expression. Methods Because STAT3 is crucial for physiologic leptin action, we used TRAP-seq to examine gene expression in LepRb neurons of mice ablated for Stat3 in LepRb neurons (Stat3LepRbKO mice), revealing the STAT3-dependent transcriptional targets of leptin. To understand roles for STAT proteins in leptin action, we also ablated STAT1 or STAT5 from LepRb neurons and expressed a constitutively-active STAT3 (CASTAT3) in LepRb neurons. Results While we also found increased Stat1 expression and STAT1-mediated transcription of leptin-regulated genes in Stat3LepRbKO mice, ablating Stat1 in LepRb neurons failed to alter energy balance (even on the Stat3LepRbKO background); ablating Stat5 in LepRb neurons also failed to alter energy balance. Importantly, expression of a constitutively-active STAT3 (CASTAT3) in LepRb neurons decreased food intake and body weight and improved metabolic parameters in leptin-deficient (ob/ob) mice, as well as in wild-type animals. Conclusions Thus, STAT3 represents the unique STAT protein required for leptin action and STAT3 suffices to mediate important components of leptin action in the absence of other LepRb signals. We used TRAP-seq to define the STAT3-dependent and independent control of gene expression in LepRb neurons. We deleted multiple STAT proteins from LepRb neurons, revealing the unique role for STAT3 in leptin action. Constitutively-active STAT3 in LepRb neurons controlled body weight and glucose in ob/ob and wild-type mice. STAT3 represents the only STAT protein required for leptin action and suffices to mediate components of leptin action.
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Affiliation(s)
- Warren Pan
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA
| | - Margaret B Allison
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Paul Sabatini
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Alan Rupp
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Jessica Adams
- Division of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Christa Patterson
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Justin C Jones
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - David P Olson
- Division of Endocrinology, Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Martin G Myers
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA.
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Audira G, Sarasamma S, Chen JR, Juniardi S, Sampurna BP, Liang ST, Lai YH, Lin GM, Hsieh MC, Hsiao CD. Zebrafish Mutants Carrying Leptin a (lepa) Gene Deficiency Display Obesity, Anxiety, Less Aggression and Fear, and Circadian Rhythm and Color Preference Dysregulation. Int J Mol Sci 2018; 19:ijms19124038. [PMID: 30551684 PMCID: PMC6320766 DOI: 10.3390/ijms19124038] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/05/2018] [Accepted: 12/11/2018] [Indexed: 01/14/2023] Open
Abstract
Leptin, a hormone secreted by peripheral adipose tissues, regulates the appetite in animals. Recently, evidence has shown that leptin also plays roles in behavioral response in addition to controlling appetite. In this study, we examined the potential function of leptin on non-appetite behaviors in zebrafish model. By using genome editing tool of Transcription activator-like effector nuclease (TALEN), we successfully knocked out leptin a (lepa) gene by deleting 4 bp within coding region to create a premature-translation stop. Morphological and appetite analysis showed the lepa KO fish display a phenotype with obese, good appetite and elevation of Agouti-related peptide (AgRP) and Ghrelin hormones, consistent with the canonical function of leptin in controlling food intake. By multiple behavior endpoint analyses, including novel tank, mirror biting, predator avoidance, social interaction, shoaling, circadian rhythm, and color preference assay, we found the lepa KO fish display an anxiogenic phenotype showing hyperactivity with rapid swimming, less freezing time, less fear to predator, loose shoaling area forming, and circadian rhythm and color preference dysregulations. Using biochemical assays, melatonin, norepinephrine, acetylcholine and serotonin levels in the brain were found to be significantly reduced in lepa KO fish, while the levels of dopamine, glycine and cortisol in the brain were significantly elevated. In addition, the brain ROS level was elevated, and the anti-oxidative enzyme catalase level was reduced. Taken together, by performing loss-of-function multiple behavior endpoint testing and biochemical analysis, we provide strong evidence for a critical role of lepa gene in modulating anxiety, aggression, fear, and circadian rhythm behaviors in zebrafish for the first time.
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Affiliation(s)
- Gilbert Audira
- Department of Chemistry, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | - Sreeja Sarasamma
- Department of Chemistry, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | - Jung-Ren Chen
- Department of Biological Science & Technology College of Medicine, I-Shou University, Kaohsiung, 82445, Taiwan.
| | - Stevhen Juniardi
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | | | - Sung-Tzu Liang
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | - Yu-Heng Lai
- Department of Chemistry, Chinese Culture University, Taipei 11114, Taiwan.
| | - Geng-Ming Lin
- Laboratory of Marine Biology and Ecology, Third Institute of Oceanography, State OceanicAdministration, Xiamen 361005, China.
| | - Ming-Chia Hsieh
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Changhua Christian Hospital, Changhua 50094, Taiwan.
| | - Chung-Der Hsiao
- Department of Chemistry, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Center of Nanotechnology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Center of Biomedical Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
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44
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Ren J, Li X, Sun G, Li S, Liang S, Li Z, Li B, Xia M. Protective effect of leptin-mediated caveolin-1 expression on neurons after spinal cord injury. Cell Calcium 2018; 76:122-128. [PMID: 30469142 DOI: 10.1016/j.ceca.2018.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 10/18/2018] [Accepted: 11/12/2018] [Indexed: 10/27/2022]
Abstract
Spinal cord injury (SCI) causes long-term disability and has no effective clinical treatment. After SCI, extracellular adenosine triphosphate (ATP) leads to an influx of extracellular Ca2+, and this Ca2+ overload causes neuronal toxicosis and apoptosis. The biological functions of leptin have been widely investigated in the central nervous system. In this study, we discovered that the administration of leptin could improve locomotor recovery following SCI. The aim of this study was to determine the neuroprotective mechanism of leptin in vivo and in vitro. The neuronal apoptosis and Ca2+ imaging signal induced by ATP were suppressed by leptin, due to elevated caveolin-1 expression. In vivo two-photon observations revealed that leptin reduced the neuronal Ca2+ imaging signal in the exposed spinal cords of live Thy1-YFP mice. In conclusion, leptin promotes locomotor functional recovery and suppresses neuronal impairment after SCI, suggesting that leptin has a promising clinical therapeutic value for treatment of SCI.
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Affiliation(s)
- Jiaan Ren
- Department of Orthopaedics, First Affiliated Hospital, China Medical University, Shenyang, People's Republic of China
| | - Xiaowei Li
- Laboratory Teaching Center, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China
| | - Guangfeng Sun
- Department of Orthopaedics, First Affiliated Hospital, China Medical University, Shenyang, People's Republic of China
| | - Shuai Li
- Laboratory Teaching Center, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China
| | - Shanshan Liang
- Laboratory Teaching Center, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China
| | - Zexiong Li
- Laboratory Teaching Center, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China
| | - Baoman Li
- Laboratory Teaching Center, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China
| | - Maosheng Xia
- Department of Orthopaedics, First Affiliated Hospital, China Medical University, Shenyang, People's Republic of China.
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Zakharova IO, Sorokoumov VN, Bayunova LV, Derkach KV, Shpakov AO. 4-oxo-1,4-dihydrocinnoline Derivative with Phosphatase 1B Inhibitor Activity Enhances Leptin Signal Transduction in Hypothalamic Neurons. J EVOL BIOCHEM PHYS+ 2018. [DOI: 10.1134/s0022093018040038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Sahu M, Anamthathmakula P, Sahu A. Hypothalamic PDE3B deficiency alters body weight and glucose homeostasis in mouse. J Endocrinol 2018; 239:93-105. [PMID: 30307157 PMCID: PMC6190684 DOI: 10.1530/joe-18-0304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Pharmacological studies have suggested hypothalamic phosphodiesterase-3B to mediate leptin and insulin action in regulation of energy homeostasis. Whereas Pde3b-null mice show altered energy homeostasis, it is unknown whether this is due to ablation of Pde3b in the hypothalamus. Thus, to address the functional significance of hypothalamic phosphodiesterase-3B, we used Pde3bflox/flox and Nkx2.1-Cre mice to generate Pde3b Nkx2.1KD mice that showed 50% reduction of phosphodiesterase-3B in the hypothalamus. To determine the effect of partial ablation of phosphodiesterase-3B in the hypothalamus on energy and glucose homeostasis, males and females were subjected to either a low- or high-fat diet for 19–21 weeks. Only female but not male Pde3b Nkx2.1KD mice on the low-fat diet showed increased body weight from 13 weeks onward with increased food intake, decreased fat pad weights and hypoleptinemia. Glucose tolerance was improved in high-fat diet-fed male Pde3b Nkx2.1KD mice in association with decreased phosphoenolpyruvate carboxykinase-1 and glucose-6-phosphatase mRNA levels in the liver. Also, insulin sensitivity was increased in male Pde3b Nkx2.1KD mice on the low-fat diet. Changes in body weight or in glucose homeostasis were not associated with any alteration in hypothalamic proopiomelanocortin, neuropepide Y and agouti-related peptide mRNA levels. These results suggest that partial loss of phosphodiesterase-3B in the hypothalamus produces a sex-specific response in body weight and glucose homeostasis, and support a role, at least in part, for hypothalamic phosphodiesterase-3B in regulation of energy and glucose homeostasis in mice.
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Affiliation(s)
- Maitrayee Sahu
- Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Prashanth Anamthathmakula
- Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Abhiram Sahu
- Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Kord Varkaneh H, Fatahi S, Tajik S, Rahmani J, Zarezadeh M, Shab-Bidar S. Dietary inflammatory index in relation to obesity and body mass index: a meta-analysis. ACTA ACUST UNITED AC 2018. [DOI: 10.1108/nfs-09-2017-0203] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Purpose
Studies investigating the association between dietary inflammatory index (DII) and body mass index (BMI) have led to inconsistent findings. Therefore, to decisively conclude, this paper aims to clarify the relationship between DII and obesity by performing meta-analysis.
Design/methodology/approach
PubMed, Scopus and Google Scholar were searched up to July 2017 using key words selected from Medical Subject Headings and other related keywords to identify all relevant articles. In total, 22 articles were entered into the meta-analysis; 22 studies compared the mean of BMI among subjects with highest versus the lowest DII and 4 studies had data on the hazard risk (HR) or odds ratio (OR) for obesity.
Findings
A meta-analysis on included studies indicated a significant association on either mean differences (MD) in BMI (MD = 0.811; 95 per cent CI: 0.365-1.256; p: 0.0001) or obesity OR (OR: 1.310; 95 per cent CI: 1.144-1.500; p = 0.000) by comparing the highest and lowest DII categories. Between-study heterogeneity was high (Cochrane Q test, p < 0.001, I2 = 98.1 per cent, df = 21, τ2 = 0.9273), and only dietary assessment methods could explain the source of heterogeneity in which 24-h dietary recalls were homogeny (I2 = 8.4 per cent, df = 2, p = 0.335).
Originality/value
The results of the present meta-analysis suggest that adherence to high DII score increased BMI and obesity. More prospective studies in different populations are needed to better clarify this relation.
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Piekarski A, Nagarajan G, Ishola P, Flees J, Greene ES, Kuenzel WJ, Ohkubo T, Maier H, Bottje WG, Cline MA, Dridi S. AMP-Activated Protein Kinase Mediates the Effect of Leptin on Avian Autophagy in a Tissue-Specific Manner. Front Physiol 2018; 9:541. [PMID: 29867578 PMCID: PMC5963154 DOI: 10.3389/fphys.2018.00541] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/26/2018] [Indexed: 12/23/2022] Open
Abstract
Autophagy, a highly conserved intracellular self-digestion process, plays an integral role in maintaining cellular homeostasis. Although emerging evidence indicate that the endocrine system regulates autophagy in mammals, there is still a scarcity of information on autophagy in avian (non-mammalian) species. Here, we show that intracerebroventricular administration of leptin reduces feed intake, modulates the expression of feeding-related hypothalamic neuropeptides, activates leptin receptor and signal transducer and activator of transcription (Ob-Rb/STAT) pathway, and significantly increases the expression of autophagy-related proteins (Atg3, Atg5, Atg7, beclin1, and LC3B) in chicken hypothalamus, liver, and muscle. Similarly, leptin treatment activates Ob-Rb/STAT pathway and increased the expression of autophagy-related markers in chicken hypothalamic organotypic cultures, muscle (QM7) and hepatocyte (Sim-CEL) cell cultures as well as in Chinese Hamster Ovary (CHO-K1) cells-overexpressing chicken Ob-Rb and STAT3. To define the downstream mediator(s) of leptin's effects on autophagy, we determined the role of the master energy sensor AMP-activated protein kinase (AMPK). Leptin treatment significantly increased the phosphorylated levels of AMPKα1/2 at Thr172 site in chicken hypothalamus and liver, but not in muscle. Likewise, AMPKα1/2 was activated by leptin in chicken hypothalamic organotypic culture and Sim-CEL, but not in QM7 cells. Blocking AMPK activity by compound C reverses the autophagy-inducing effect of leptin. Together, these findings indicate that AMPK mediates the effect of leptin on chicken autophagy in a tissue-specific manner.
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Affiliation(s)
- Alissa Piekarski
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Gurueswar Nagarajan
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Peter Ishola
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Joshua Flees
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Elizabeth S. Greene
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Wayne J. Kuenzel
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Takeshi Ohkubo
- College of Agriculture, Ibaraki University, Ibaraki, Japan
| | - Helena Maier
- Nidovirus-Cell Interactions Group, The Pirbright Institute, Woking, United Kingdom
| | - Walter G. Bottje
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Mark A. Cline
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Sami Dridi
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR, United States
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Huang Y, He Z, Gao Y, Lieu L, Yao T, Sun J, Liu T, Javadi C, Box M, Afrin S, Guo H, Williams KW. Phosphoinositide 3-Kinase Is Integral for the Acute Activity of Leptin and Insulin in Male Arcuate NPY/AgRP Neurons. J Endocr Soc 2018; 2:518-532. [PMID: 29850651 PMCID: PMC5961025 DOI: 10.1210/js.2018-00061] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/23/2018] [Indexed: 11/19/2022] Open
Abstract
Neuropeptide Y (NPY)/Agouti-related protein (AgRP) neurons in the arcuate nucleus of the hypothalamus are part of a neuroendocrine feedback loop that regulates feeding behavior and glucose homeostasis. NPY/AgRP neurons sense peripheral signals (including the hormones leptin, insulin, and ghrelin) and integrate those signals with inputs from other brain regions. These inputs modify both long-term changes in gene transcription and acute changes in the electrical activity of these neurons, leading to a coordinated response to maintain energy and glucose homeostasis. However, the mechanisms by which the hormones insulin and leptin acutely modify the electrical activity of these neurons remain unclear. In this study, we show that loss of the phosphoinositide 3-kinase catalytic subunits p110α and p110β in AgRP neurons abrogates the leptin- and insulin-induced inhibition of AgRP neurons. Moreover, continual disruption of p110α and p110β in AgRP neurons results in increased weight gain. The increased adiposity was concomitant with a hypometabolic phenotype: decreased energy expenditure independent of changes in food intake. Deficiency of p110α and p110β in AgRP neurons also impaired glucose homeostasis and insulin sensitivity. In summary, these data highlight the requirement of both p110α and p110β in AgRP neurons for the proper regulation of energy balance and glucose homeostasis.
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Affiliation(s)
- Yiru Huang
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Zhenyan He
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Yong Gao
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas.,National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Linh Lieu
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Ting Yao
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Jia Sun
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Tiemin Liu
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Chris Javadi
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Maria Box
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Sadia Afrin
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Hongbo Guo
- The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Kevin W Williams
- Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, Texas
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Abstract
Obesity represents the single most important risk factor for early disability and death in developed societies, and the incidence of obesity remains at staggering levels. CNS systems that modulate energy intake and expenditure in response to changes in body energy stores serve to maintain constant body adiposity; the adipocyte-derived hormone leptin and its receptor (LEPR) represent crucial regulators of these systems. As in the case of insulin resistance, a variety of mechanisms (including feedback inhibition, inflammation, gliosis and endoplasmic reticulum stress) have been proposed to interfere with leptin action and impede the systems that control body energy homeostasis to promote or maintain obesity, although the relative importance and contribution of each of these remain unclear. However, LEPR signalling may be increased (rather than impaired) in common obesity, suggesting that any obesity-associated defects in leptin action must result from lesions somewhere other than the initial LEPR signal. It is also possible that increased LEPR signalling could mediate some of the obesity-associated changes in hypothalamic function.
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