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Polymorphisms in the leptin (rs7799039) gene are associated with an increased risk of excessive gestational weight gain but not with leptin concentration during pregnancy. Nutr Res 2017; 47:53-62. [PMID: 29241578 DOI: 10.1016/j.nutres.2017.09.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 09/03/2017] [Accepted: 09/12/2017] [Indexed: 11/22/2022]
Abstract
Single nucleotide polymorphisms (SNPs) in leptin (LEP) and leptin receptor (LEPR) have been shown to be linked to obesity-related metabolic markers and phenotype. Therefore, we hypothesized that the LEP-rs7799039 and LEPR-rs1137101 SNPs are related to the risk of pre-pregnancy overweight/obesity (body mass index ≥25 kg/m2) as well as to excessive gestational weight gain (GWG) and high concentrations of leptin throughout pregnancy. We investigated a prospective cohort of 147 Brazilian pregnant women through weeks 5-13, 20-26, and 30-36 of gestation. Genetic variants of LEP and LEPR were analyzed by real-time polymerase chain reaction and leptin by enzyme-linked immunosorbent assay. Statistical analyses included multiple linear regression, linear mixed effects, and Poisson regression models. Genotype AA carriers for the LEP-rs7799039 gene maintained a lower body weight throughout pregnancy compared with those with genotypes GG or GA + GG (βAAvsGG = -7.91 kg; 95% confidence interval [CI], -14.21 to -1.61; P = .01; and βAAvsGA + GG = -7.66 kg; 95% CI, -14.07 to -1.25; P = .02). The A allele was significantly associated with an increased risk for excessive GWG (relative riskLEP-GAvsGG, 2.16; 95% CI, 1.23-3.80; and relative riskLEP-AAvsGG, 2.37; 95% CI, 1.04-5.39). Neither the LEP-rs7799039 nor LEPR-rs1137101 SNP was significantly associated with pre-pregnancy overweight/obesity risk and leptin concentrations during pregnancy. In conclusion, our results indicate that women who had the AA genotype for LEP-rs7799039 displayed a lower body weight throughout pregnancy compared with GG or GA + GG carriers. LEP-rs7799039 was significantly associated with an increased risk for excessive GWG, but the results do not support significant associations of the LEP-rs7799039 and LEPR-rs1137101 polymorphisms with pre-pregnancy overweight/obesity risk and leptin concentrations throughout pregnancy.
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PTPRJ Inhibits Leptin Signaling, and Induction of PTPRJ in the Hypothalamus Is a Cause of the Development of Leptin Resistance. Sci Rep 2017; 7:11627. [PMID: 28912580 PMCID: PMC5599550 DOI: 10.1038/s41598-017-12070-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 09/04/2017] [Indexed: 12/17/2022] Open
Abstract
Leptin signaling in the hypothalamus plays a crucial role in the regulation of body weight. Leptin resistance, in which leptin signaling is disrupted, is a major obstacle to the improvement of obesity. We herein demonstrated that protein tyrosine phosphatase receptor type J (Ptprj) is expressed in hypothalamic neurons together with leptin receptors, and that PTPRJ negatively regulates leptin signaling by inhibiting the activation of JAK2, the primary tyrosine kinase in leptin signaling, through the dephosphorylation of Y813 and Y868 in JAK2 autophosphorylation sites. Leptin signaling is enhanced in Ptprj-deficient mice, and they exhibit lower weight gain than wild-type mice because of a reduced food intake. Diet-induced obesity and the leptin treatment up-regulated PTPRJ expression in the hypothalamus, while the overexpression of PTPRJ induced leptin resistance. Thus, the induction of PTPRJ is a factor contributing to the development of leptin resistance, and the inhibition of PTPRJ may be a potential strategy for improving obesity.
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103
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Romualdi D, Immediata V, De Cicco S, Tagliaferri V, Lanzone A. Neuroendocrine Regulation of Food Intake in Polycystic Ovary Syndrome. Reprod Sci 2017; 25:644-653. [PMID: 28874103 DOI: 10.1177/1933719117728803] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Several peripheral and central signals are involved in the sophisticated regulation of food intake. Women with polycystic ovary syndrome (PCOS) are prone to consume a diet higher in saturated fat and foods with high glycemic index and show impaired appetite regulation and measures of satiety. As a consequence, obesity, mostly of the central type, is prevalent in the syndrome and worsens the endocrine and metabolic profile of the affected patients. This review article briefly analyzes the current knowledge about the neuroendocrine mechanisms underlying the interplay between feeding behavior, obesity, and reproductive abnormalities in PCOS.
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Affiliation(s)
- Daniela Romualdi
- 1 Department of Obstetrics and Gynaecology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Valentina Immediata
- 1 Department of Obstetrics and Gynaecology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Simona De Cicco
- 1 Department of Obstetrics and Gynaecology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Valeria Tagliaferri
- 1 Department of Obstetrics and Gynaecology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Antonio Lanzone
- 1 Department of Obstetrics and Gynaecology, Università Cattolica del Sacro Cuore, Rome, Italy
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Derkach KV, Bondareva VM, Trashkov AP, Chistyakova OV, Verlov NA, Shpakov AO. Metabolic and hormonal indices in rats with a prolonged model of the metabolic syndrome induced by a high-carbohydrate and high-fat diet. ADVANCES IN GERONTOLOGY 2017. [DOI: 10.1134/s2079057017020035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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105
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Wang H, Xu M, Kong Q, Sun P, Yan F, Tian W, Wang X. Research and progress on ClC‑2 (Review). Mol Med Rep 2017; 16:11-22. [PMID: 28534947 PMCID: PMC5482133 DOI: 10.3892/mmr.2017.6600] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 02/13/2017] [Indexed: 12/22/2022] Open
Abstract
Chloride channel 2 (ClC-2) is one of the nine mammalian members of the ClC family. The present review discusses the molecular properties of ClC‑2, including CLCN2, ClC‑2 promoter and the structural properties of ClC‑2 protein; physiological properties; functional properties, including the regulation of cell volume. The effects of ClC‑2 on the digestive, respiratory, circulatory, nervous and optical systems are also discussed, in addition to the mechanisms involved in the regulation of ClC‑2. The review then discusses the diseases associated with ClC‑2, including degeneration of the retina, Sjögren's syndrome, age‑related cataracts, degeneration of the testes, azoospermia, lung cancer, constipation, repair of impaired intestinal mucosa barrier, leukemia, cystic fibrosis, leukoencephalopathy, epilepsy and diabetes mellitus. It was concluded that future investigations of ClC‑2 are likely to be focused on developing specific drugs, activators and inhibitors regulating the expression of ClC‑2 to treat diseases associated with ClC‑2. The determination of CLCN2 is required to prevent and treat several diseases associated with ClC‑2.
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Affiliation(s)
- Hongwei Wang
- Department of Ophthalmology, People's Hospital of Jingjiang, Jingjiang, Jiangsu 214500, P.R. China
| | - Minghui Xu
- Library, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
| | - Qingjie Kong
- School of Computer Science and Information Technology, Northeast Normal University, Changchun, Jilin 130024, P.R. China
| | - Peng Sun
- Department of Ophthalmology, The First Affiliated Hospital of Jiamusi University, Jiamusi, Heilongjiang 154000, P.R. China
| | - Fengyun Yan
- Assets Division, Harbin University of Science and Technology, Harbin, Heilongjiang 150080, P.R. China
| | - Wenying Tian
- Library, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
| | - Xin Wang
- Library, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
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106
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Nappo A, González-Gil EM, Ahrens W, Bammann K, Michels N, Moreno LA, Kourides Y, Iacoviello L, Mårild S, Fraterman A, Molnàr D, Veidebaum T, Siani A, Russo P. Analysis of the association of leptin and adiponectin concentrations with metabolic syndrome in children: Results from the IDEFICS study. Nutr Metab Cardiovasc Dis 2017; 27:543-551. [PMID: 28511904 DOI: 10.1016/j.numecd.2017.04.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/20/2017] [Accepted: 04/08/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND AIMS Adipokines may play a role in the pathogenesis of the metabolic syndrome (MetS) in children. We aimed to evaluate the association of leptin, adiponectin, and its ratio (L/A ratio) with the metabolic syndrome (MetS) in a subsample of the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS) cohort. METHODS AND RESULTS Leptin, adiponectin and MetS parameters were measured in a subsample of 1253 children (3-9.9 years) participating to the IDEFICS study, grouped as: Non-OW (underweight/normal weight) and OW/Ob (overweight/obese). MetS was defined using the sex- and age-specific cut-offs based on the distribution of MetS components in the IDEFICS cohort. The prevalence of the MetS among OW/Ob was 24.8% and 27.1% in boys and girls respectively, whereas ≤2% among Non-OW. OW/Ob had significantly higher leptin and L/A ratio as compared to Non-OW. Significantly higher leptin was found in OW/Ob with MetS as compared with OW/Ob without MetS. Significantly lower adiponectin was observed only in OW/Ob girls as compared to Non-OW. A 1SD increase in leptin and L/A ratio z-scores or a 1SD decrease in adiponectin z-score were significantly associated with higher risk of MetS. After adjustment for BMI or body fat mass (BFM) the association remained significant only for leptin. CONCLUSION We showed that in European children, higher leptin concentration is associated with MetS, even after adjusting for BMI or BFM, confirming an early role of leptin in MetS, while the association of adiponectin with MetS seems be mediated by body fat in this age range.
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Affiliation(s)
- A Nappo
- Institute of Food Sciences, National Research Council, Avellino, Italy
| | - E M González-Gil
- GENUD (Growth, Exercise, Nutrition and Development) Research Group, University of Zaragoza, Zaragoza, Spain
| | - W Ahrens
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany; Institute of Statistics, Faculty of Mathematics and Computer Science, Bremen University, Bremen, Germany
| | - K Bammann
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany; Institute for Public Health and Nursing Research (IPP), University of Bremen, Bremen, Germany
| | - N Michels
- Department of Public Health, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - L A Moreno
- GENUD (Growth, Exercise, Nutrition and Development) Research Group, University of Zaragoza, Zaragoza, Spain
| | - Y Kourides
- Research and Education Institute of Child Health, Strovolos, Cyprus
| | - L Iacoviello
- Department of Epidemiology and Prevention, Unit of Molecular and Nutritional Epidemiology, IRCCS Istituto Neurologico Mediterraneo Neuromed, Pozzilli, Italy
| | - S Mårild
- Department of Paediatrics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - A Fraterman
- Laboratoriumsmedizin Dortmund, Eberhard & Partner Dortmund, Germany
| | - D Molnàr
- Department of Paediatrics, Medical Faculty, University of Pécs, Pécs, Hungary
| | - T Veidebaum
- National Institute for Health Development, Tallinn, Estonia
| | - A Siani
- Institute of Food Sciences, National Research Council, Avellino, Italy.
| | - P Russo
- Institute of Food Sciences, National Research Council, Avellino, Italy
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107
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Body and liver fat content and adipokines in schizophrenia: a magnetic resonance imaging and spectroscopy study. Psychopharmacology (Berl) 2017; 234:1923-1932. [PMID: 28315932 DOI: 10.1007/s00213-017-4598-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 03/11/2017] [Indexed: 12/24/2022]
Abstract
RATIONALE Although antipsychotic treatment often causes weight gain and lipid abnormalities, quantitative analyses of tissue-specific body fat content and its distribution along with adipokines have not been reported for antipsychotic-treated patients. OBJECTIVES The purposes of the present study were to quantitatively assess abdominal and liver fat in patients with schizophrenia on antipsychotic treatment and age- and body mass index (BMI)-matched healthy controls and to evaluate their associations with plasma leptin and adiponectin levels. METHODS In 13 schizophrenia patients on antipsychotic treatment and 11 age- and BMI-matched controls, we simultaneously quantified visceral and subcutaneous fat content using T1-weighted magnetic resonance imaging and liver fat content by 1H magnetic resonance spectroscopy. Associations of tissue-specific fat content with plasma levels of leptin and adiponectin were evaluated. RESULTS Plasma adiponectin level (μg/mL) was not statistically different between groups (7.02 ± 2.67 vs. 7.59 ± 2.92), whereas plasma leptin level (ng/mL) trended to be higher in patients than in controls (11.82 ± 7.89 vs. 7.93 ± 5.25). The values of liver fat (%), visceral fat (L), and subcutaneous fat (L) were 9.64 ± 8.03 vs. 7.07 ± 7.35, 4.41 ± 1.64 vs. 3.31 ± 1.97, and 8.37 ± 3.34 vs. 7.16 ± 2.99 in patients vs. controls, respectively. Liver fat content was inversely correlated with adiponectin in controls (r = - 0.87, p < 0.001) but not in patients (r = - 0.26, p = 0.39). In both groups, visceral fat was inversely associated with adiponectin (controls : r = - 0.66, p = 0.03; patients : r = - 0.65, p = 0.02), while subcutaneous fat was positively correlated with leptin (controls : r = 0.90, p < 0.001; patients : r = 0.67, p = 0.01). CONCLUSIONS These findings suggest that antipsychotic treatment may disrupt the physiological relationship between liver fat content and adiponectin but does not essentially affect the associations of adiponectin and leptin with visceral and subcutaneous compartments.
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108
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Ramos-Lobo AM, Donato J. The role of leptin in health and disease. Temperature (Austin) 2017; 4:258-291. [PMID: 28944270 DOI: 10.1080/23328940.2017.1327003] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/27/2017] [Accepted: 05/02/2017] [Indexed: 02/07/2023] Open
Abstract
Leptin is a master regulator of energy balance and body adiposity. Additionally, leptin exerts important control on glucose homeostasis, thermogenesis, autonomic nervous system and neuroendocrine axes. In metabolic diseases, such as obesity and diabetes mellitus, leptin signaling may be compromised, indicating the important role of this hormone in the etiology and pathophysiological manifestations of these conditions. In the present manuscript, we reviewed important concepts of leptin signaling, as well as about the effects of leptin on several biologic functions. We also discussed the possible therapeutic use of leptin administration and how our current obesogenic environment contributes to the development of leptin resistance. Our objective was to provide a comprehensive and state-of-the-art review about the importance of leptin to maintain the homeostasis and during pathological conditions.
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Affiliation(s)
- Angela M Ramos-Lobo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
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109
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Qiao F, Longley KR, Feng S, Schnack S, Gao H, Li Y, Schlenker EH, Wang H. Reduced body weight gain in ubiquilin-1 transgenic mice is associated with increased expression of energy-sensing proteins. Physiol Rep 2017; 5:e13260. [PMID: 28420763 PMCID: PMC5408289 DOI: 10.14814/phy2.13260] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/22/2017] [Accepted: 03/24/2017] [Indexed: 12/14/2022] Open
Abstract
Ubiquilin-1 (Ubqln1), a ubiquitin-like protein, is implicated in a variety of pathophysiological processes, but its role in mediating body weight gain or metabolism has not been determined. Here, we demonstrate that global overexpression of Ubqln1 in a transgenic (Tg) mouse reduces the animal's body weight gain. The decreased body weight gain in Tg mice is associated with lower visceral fat content and higher metabolic rate. The Ubqln1 Tg mice exhibited reduced leptin and insulin levels as well as increased insulin sensitivity manifested by homeostatic model assessment of insulin resistance. Additionally, the reduced body weight in Tg mice was associated with the upregulation of two energy-sensing proteins, sirtuin1 (SIRT1) in the hypothalamus and AMP-activated protein kinase (AMPK) in the skeletal muscle. Consistent with the in vivo results, overexpression of Ubqln1 significantly increased SIRT1 and AMPK levels in the mouse embryonic fibroblast cell culture. Thus, our results not only establish the link between Ubqln1 and body weight regulation but also indicate that the metabolic function of Ubqln1 on body weight may be through regulating energy-sensing proteins.
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Affiliation(s)
- Fangfang Qiao
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Kirsty R Longley
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Shelley Feng
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Sabrina Schnack
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Hongbo Gao
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Yifan Li
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Evelyn H Schlenker
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Hongmin Wang
- Division of Basic Biomedical Sciences and Center for Brain and Behavior Research, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
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110
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Lin H, Hu M, Yan Y, Zhang H. The effect of exercise on adiponectin and leptin levels in overweight or obese subjects: a meta-analysis of randomized controlled trials. SPORT SCIENCES FOR HEALTH 2017. [DOI: 10.1007/s11332-017-0358-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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111
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Yuan D, Yi X, Zhao Y, Poon CD, Bullock KM, Hansen KM, Salameh TS, Farr SA, Banks WA, Kabanov AV. Intranasal delivery of N-terminal modified leptin-pluronic conjugate for treatment of obesity. J Control Release 2017; 263:172-184. [PMID: 28344017 DOI: 10.1016/j.jconrel.2017.03.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 03/07/2017] [Accepted: 03/17/2017] [Indexed: 10/19/2022]
Abstract
Leptin is an adipocyte-secreted hormone that is delivered via a specific transport system across the blood-brain barrier (BBB) to the brain where it acts on the hypothalamus receptors to control appetite and thermogenesis. Peripheral resistance to leptin due to its impaired brain delivery prevents therapeutic use of leptin in overweight and moderately obese patients. To address this problem, we modified the N-terminal amine of leptin with Pluronic P85 (LepNP85) and administered this conjugate intranasally using the nose-to-brain (INB) route to bypass the BBB. We compared this conjugate with the native leptin, the N-terminal leptin conjugate with poly(ethylene glycol) (LepNPEG5K), and two conjugates of leptin with Pluronic P85 attached randomly to the lysine amino groups of the hormone. Compared to the random conjugates of leptin with P85, LepNP85 has shown higher affinity upon binding with the leptin receptor, and similarly to native hormone activated hypothalamus receptors after direct injection into brain. After INB delivery, LepNP85 conjugate was transported to the brain and accumulated in the hypothalamus and hippocampus to a greater extent than the native leptin and LepNPEG5K and activated leptin receptors in hypothalamus at lower dose than native leptin. Our work suggests that LepNP85 can access the brain directly after INB delivery and confirms our hypothesis that the improvement in brain accumulation of this conjugate is due to its enhanced brain absorption. In conclusion, the LepNP85 with optimized conjugation chemistry is a promising candidate for treatment of obesity.
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Affiliation(s)
- Dongfen Yuan
- Center for Nanotechnology in Drug Delivery, Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Xiang Yi
- Center for Nanotechnology in Drug Delivery, Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Yuling Zhao
- Center for Nanotechnology in Drug Delivery, Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Chi-Duen Poon
- Research Computer Center, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Kristin M Bullock
- Research and Development, Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
| | - Kim M Hansen
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA; Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - Therese S Salameh
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA; Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - Susan A Farr
- Research and Development, VA Medical Center and Division of Geriatrics, School of Medicine, St. Louis University, St. Louis, MO 63110, USA
| | - William A Banks
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA; Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - Alexander V Kabanov
- Center for Nanotechnology in Drug Delivery, Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA; Laboratory of Chemical Design of Bionanomaterials, Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119992, Russia.
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112
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Abstract
The aim of this study was to investigate whether neonatal maternal separation (MS) - chronic stress experience in early life - affects the anorectic efficacy of leptin in the offspring at adolescence. Sprague-Dawley pups were separated from the dam daily for 3 h during postnatal day 1-14 or left undisturbed as non-handled controls (NH). NH and MS male pups received an intraperitoneal leptin (100 μg/kg) or saline on postnatal day (PND) 28, and then food intake and body weight gain were recorded. The hypothalamic levels of leptin-signalling-related genes, phosphorylated signal transducer and activator of transcription-3 (pSTAT3) and protein-tyrosine phosphatase 1B (PTP1B) were examined at 40 min after a single injection of leptin on PND 39 by immunohistochemistry and Western blot analysis. Leptin-induced suppressions in food intake and weight gain was observed in NH pups, but not in MS. Leptin increased pSTAT3 in the hypothalamic arcuate nucleus of NH pups, but not of MS. Interestingly, basal levels of the hypothalamic PTP1B and pSTAT3 were increased in MS pups compared with NH controls. The results suggest that neonatal MS experience may blunt the anorectic efficacy of leptin later in life, possibly in relation with increased expressions of PTP1B and/or pSTAT3 in the hypothalamus.
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113
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The Effects of Myo-Inositol and B and D Vitamin Supplementation in the db/+ Mouse Model of Gestational Diabetes Mellitus. Nutrients 2017; 9:nu9020141. [PMID: 28212289 PMCID: PMC5331572 DOI: 10.3390/nu9020141] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 02/02/2017] [Accepted: 02/09/2017] [Indexed: 12/16/2022] Open
Abstract
Gestational diabetes mellitus (GDM) is a growing concern, affecting an increasing number of pregnant women worldwide. By predisposing both the affected mothers and children to future disease, GDM contributes to an intergenerational cycle of obesity and diabetes. In order to stop this cycle, safe and effective treatments for GDM are required. This study sought to determine the treatment effects of dietary supplementation with myo-inositol (MI) and vitamins B2, B6, B12, and D in a mouse model of GDM (pregnant db/+ dams). In addition, the individual effects of vitamin B2 were examined. Suboptimal B2 increased body weight and fat deposition, decreased GLUT4 adipose tissue expression, and increased expression of inflammatory markers. MI supplementation reduced weight and fat deposition, and reduced expression of inflammatory markers in adipose tissue of mice on suboptimal B2. MI also significantly reduced the hyperleptinemia observed in db/+ mice, when combined with supplemented B2. MI was generally associated with adipose tissue markers of improved insulin sensitivity and glucose uptake, while the combination of vitamins B2, B6, B12, and D was associated with a reduction in adipose inflammatory marker expression. These results suggest that supplementation with MI and vitamin B2 could be beneficial for the treatment/prevention of GDM.
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114
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Evans MC, Anderson GM. Neuroendocrine integration of nutritional signals on reproduction. J Mol Endocrinol 2017; 58:R107-R128. [PMID: 28057770 DOI: 10.1530/jme-16-0212] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 12/28/2022]
Abstract
Reproductive function in mammals is energetically costly and therefore tightly regulated by nutritional status. To enable this integration of metabolic and reproductive function, information regarding peripheral nutritional status must be relayed centrally to the gonadotropin-releasing hormone (GNRH) neurons that drive reproductive function. The metabolically relevant hormones leptin, insulin and ghrelin have been identified as key mediators of this 'metabolic control of fertility'. However, the neural circuitry through which they act to exert their control over GNRH drive remains incompletely understood. With the advent of Cre-LoxP technology, it has become possible to perform targeted gene-deletion and gene-rescue experiments and thus test the functional requirement and sufficiency, respectively, of discrete hormone-neuron signaling pathways in the metabolic control of reproductive function. This review discusses the findings from these investigations, and attempts to put them in context with what is known from clinical situations and wild-type animal models. What emerges from this discussion is clear evidence that the integration of nutritional signals on reproduction is complex and highly redundant, and therefore, surprisingly difficult to perturb. Consequently, the deletion of individual hormone-neuron signaling pathways often fails to cause reproductive phenotypes, despite strong evidence that the targeted pathway plays a role under normal physiological conditions. Although transgenic studies rarely reveal a critical role for discrete signaling pathways, they nevertheless prove to be a good strategy for identifying whether a targeted pathway is absolutely required, critically involved, sufficient or dispensable in the metabolic control of fertility.
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Affiliation(s)
- Maggie C Evans
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago School of Medical Sciences, Dunedin, New Zealand
| | - Greg M Anderson
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago School of Medical Sciences, Dunedin, New Zealand
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115
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Abstract
The gastrointestinal alterations associated with the consumption of an obesogenic diet, such as inflammation, permeability impairment and oxidative stress, have been poorly explored in both diet-induced obesity (DIO) and genetic obesity. The aim of the present study was to examine the impact of an obesogenic diet on the gut health status of DIO rats in comparison with the Zucker (fa/fa) rat leptin receptor-deficient model of genetic obesity over time. For this purpose, female Wistar rats (n 48) were administered a standard or a cafeteria diet (CAF diet) for 12, 14·5 or 17 weeks and were compared with fa/fa Zucker rats fed a standard diet for 10 weeks. Morphometric variables, plasma biochemical parameters, myeloperoxidase (MPO) activity and reactive oxygen species (ROS) levels in the ileum were assessed, as well as the expressions of proinflammatory genes (TNF-α and inducible nitric oxide synthase (iNOS)) and intestinal permeability genes (zonula occludens-1, claudin-1 and occludin). Both the nutritional model and the genetic obesity model showed increased body weight and metabolic alterations at the final time point. An increase in intestinal ROS production and MPO activity was observed in the gastrointestinal tracts of rats fed a CAF diet but not in the genetic obesity model. TNF-α was overexpressed in the ileum of both CAF diet and fa/fa groups, and ileal inflammation was associated with the degree of obesity and metabolic alterations. Interestingly, the 17-week CAF group and the fa/fa rats exhibited alterations in the expressions of permeability genes. Relevantly, in the hyperlipidic refined sugar diet model of obesity, the responses to chronic energy overload led to time-dependent increases in gut inflammation and oxidative stress.
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Exercise Training Attenuates the Dysregulated Expression of Adipokines and Oxidative Stress in White Adipose Tissue. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:9410954. [PMID: 28168013 PMCID: PMC5266865 DOI: 10.1155/2017/9410954] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/25/2016] [Indexed: 12/15/2022]
Abstract
Obesity-induced inflammatory changes in white adipose tissue (WAT), which caused dysregulated expression of inflammation-related adipokines involving tumor necrosis factor-α and monocyte chemoattractant protein-1, contribute to the development of insulin resistance. Moreover, current literature reports state that WAT generates reactive oxygen species (ROS), and the enhanced production of ROS in obese WAT has been closely associated with the dysregulated expression of adipokines in WAT. Therefore, the reduction in excess WAT and oxidative stress that results from obesity is thought to be one of the important strategies in preventing and improving lifestyle-related diseases. Exercise training (TR) not only brings about a decrease in WAT mass but also attenuates obesity-induced dysregulated expression of the adipokines in WAT. Furthermore, some reports indicate that TR affects the generation of oxidative stress in WAT. This review outlines the impact of TR on the expression of inflammation-related adipokines and oxidative stress in WAT.
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117
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Engin A. Obesity-associated Breast Cancer: Analysis of risk factors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 960:571-606. [PMID: 28585217 DOI: 10.1007/978-3-319-48382-5_25] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Furthermore, obese women are at higher risk of all-cause and breast cancer specific mortality when compared to non-obese women with breast cancer. In this context, increased levels of estrogens due to excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, hyperactivation of insulin-like growth factors (IGFs) pathways, adipocyte-derived adipokines, hypercholesterolemia and excessive oxidative stress contribute to the development of breast cancer in obese women. While higher breast cancer risk with hormone replacement therapy is particularly evident among lean women, in postmenopausal women who are not taking exogenous hormones, general obesity is a significant predictor for breast cancer. Moreover, increased plasma cholesterol leads to accelerated tumor formation and exacerbates their aggressiveness. In contrast to postmenopausal women, premenopausal women with high BMI are inversely associated with breast cancer risk. Nevertheless, life-style of women for breast cancer risk is regulated by avoiding the overweight and a high-fat diet. Estrogen-plus-progestin hormone therapy users for more than 5 years have elevated risks of both invasive ductal and lobular breast cancer. Additionally, these cases are more commonly node-positive and have a higher cancer-related mortality. Collectively, in this chapter, the impacts of obesity-related estrogen, cholesterol, saturated fatty acid, leptin and adiponectin concentrations, aromatase activity, leptin and insulin resistance on breast cancer patients are evaluated. Obesity-related prognostic factors of breast cancer also are discussed at molecular basis.
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Affiliation(s)
- Atilla Engin
- Faculty of Medicine, Department of General Surgery, Gazi University, Besevler, Ankara, Turkey. .,, Mustafa Kemal Mah. 2137. Sok. 8/14, 06520, Cankaya, Ankara, Turkey.
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Engin A. Diet-Induced Obesity and the Mechanism of Leptin Resistance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 960:381-397. [PMID: 28585208 DOI: 10.1007/978-3-319-48382-5_16] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Leptin signaling blockade by chronic overstimulation of the leptin receptor or hypothalamic pro-inflammatory responses due to elevated levels of saturated fatty acid can induce leptin resistance by activating negative feedback pathways. Although, long form leptin receptor (Ob-Rb) initiates leptin signaling through more than seven different signal transduction pathways, excessive suppressor of cytokine signaling-3 (SOCS-3) activity is a potential mechanism for the leptin resistance that characterizes human obesity. Because the leptin-responsive metabolic pathways broadly integrate with other neurons to control energy balance, the methods used to counteract the leptin resistance has extremely limited effect. In this chapter, besides the impairment of central and peripheral leptin signaling pathways, limited access of leptin to central nervous system (CNS) through blood-brain barrier, mismatch between high leptin and the amount of leptin receptor expression, contradictory effects of cellular and circulating molecules on leptin signaling, the connection between leptin signaling and endoplasmic reticulum (ER) stress and self-regulation of leptin signaling has been discussed in terms of leptin resistance.
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Affiliation(s)
- Atilla Engin
- Faculty of Medicine, Department of General Surgery, Gazi University, Besevler, Ankara, Turkey.
- , Mustafa Kemal Mah. 2137. Sok. 8/14, 06520, Cankaya, Ankara, Turkey.
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119
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Fasting selectively blocks development of acute lymphoblastic leukemia via leptin-receptor upregulation. Nat Med 2016; 23:79-90. [PMID: 27941793 DOI: 10.1038/nm.4252] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 11/14/2016] [Indexed: 12/17/2022]
Abstract
New therapeutic approaches are needed to treat leukemia effectively. Dietary restriction regimens, including fasting, have been considered for the prevention and treatment of certain solid tumor types. However, whether and how dietary restriction affects hematopoietic malignancies is unknown. Here we report that fasting alone robustly inhibits the initiation and reverses the leukemic progression of both B cell and T cell acute lymphoblastic leukemia (B-ALL and T-ALL, respectively), but not acute myeloid leukemia (AML), in mouse models of these tumors. Mechanistically, we found that attenuated leptin-receptor (LEPR) expression is essential for the development and maintenance of ALL, and that fasting inhibits ALL development by upregulation of LEPR and its downstream signaling through the protein PR/SET domain 1 (PRDM1). The expression of LEPR signaling-related genes correlated with the prognosis of pediatric patients with pre-B-ALL, and fasting effectively inhibited B-ALL growth in a human xenograft model. Our results indicate that the effects of fasting on tumor growth are cancer-type dependent, and they suggest new avenues for the development of treatment strategies for leukemia.
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120
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Haley MJ, Lawrence CB. Obesity and stroke: Can we translate from rodents to patients? J Cereb Blood Flow Metab 2016; 36:2007-2021. [PMID: 27655337 PMCID: PMC5134197 DOI: 10.1177/0271678x16670411] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 08/04/2016] [Accepted: 08/09/2016] [Indexed: 12/15/2022]
Abstract
Obesity is a risk factor for stroke and is consequently one of the most common co-morbidities found in patients. There is therefore an identified need to model co-morbidities preclinically to allow better translation from bench to bedside. In preclinical studies, both diet-induced and genetically obese rodents have worse stroke outcome, characterised by increased ischaemic damage and an altered inflammatory response. However, clinical studies have reported an 'obesity paradox' in stroke, characterised by reduced mortality and morbidity in obese patients. We discuss the potential reasons why the preclinical and clinical studies may not agree, and review the mechanisms identified in preclinical studies through which obesity may affects stroke outcome. We suggest inflammation plays a central role in this relationship, as obesity features increases in inflammatory mediators such as C-reactive protein and interleukin-6, and chronic inflammation has been linked to worse stroke risk and outcome.
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Affiliation(s)
- Michael J Haley
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Catherine B Lawrence
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
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121
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Mikulášková B, Maletínská L, Zicha J, Kuneš J. The role of food intake regulating peptides in cardiovascular regulation. Mol Cell Endocrinol 2016; 436:78-92. [PMID: 27450151 DOI: 10.1016/j.mce.2016.07.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 07/07/2016] [Accepted: 07/19/2016] [Indexed: 12/11/2022]
Abstract
Obesity is a risk factor that worsens cardiovascular events leading to higher morbidity and mortality. However, the exact mechanisms of relation between obesity and cardiovascular events are unclear. Nevertheless, it has been demonstrated that pharmacological therapy for obesity has great potential to improve some cardiovascular problems. Therefore, it is important to determine the common mechanisms regulating both food intake and blood pressure. Several hormones produced by peripheral tissues work together with neuropeptides involved in the regulation of both food intake and blood pressure. Anorexigenic (food intake lowering) hormones such as leptin, glucagon-like peptide-1 and cholecystokinin cooperate with α-melanocyte-stimulating hormone, cocaine- and amphetamine-regulated peptide as well as prolactin-releasing peptide. Curiously their collective actions result in increased sympathetic activity, especially in the kidney, which could be one of the factors responsible for the blood pressure increases seen in obesity. On the other hand, orexigenic (food intake enhancing) peptides, especially ghrelin released from the stomach and acting in the brain, cooperates with orexins, neuropeptide Y, melanin-concentrating hormone and galanin, which leads to decreased sympathetic activity and blood pressure. This paradox should be intensively studied in the future. Moreover, it is important to know that the hypothalamus together with the brainstem seem to be major structures in the regulation of food intake and blood pressure. Thus, the above mentioned regions might be essential brain components in the transmission of peripheral signals to the central effects. In this short review, we summarize the current information on cardiovascular effects of food intake regulating peptides.
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Affiliation(s)
- B Mikulášková
- Institute of Physiology AS CR, Prague, Czech Republic; Institute of Organic Chemistry and Biochemistry AS CR, Prague, Czech Republic
| | - L Maletínská
- Institute of Organic Chemistry and Biochemistry AS CR, Prague, Czech Republic
| | - J Zicha
- Institute of Physiology AS CR, Prague, Czech Republic
| | - J Kuneš
- Institute of Physiology AS CR, Prague, Czech Republic; Institute of Organic Chemistry and Biochemistry AS CR, Prague, Czech Republic.
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Prunin is a highly potent flavonoid from Prunus davidiana stems that inhibits protein tyrosine phosphatase 1B and stimulates glucose uptake in insulin-resistant HepG2 cells. Arch Pharm Res 2016; 40:37-48. [DOI: 10.1007/s12272-016-0852-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 10/24/2016] [Indexed: 12/20/2022]
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Rostás I, Tenk J, Mikó A, Füredi N, Soós S, Solymár M, Lengyel A, Székely M, Gaszner B, Feller D, Pétervári E, Balaskó M. Age-related changes in acute central leptin effects on energy balance are promoted by obesity. Exp Gerontol 2016; 85:118-127. [PMID: 27780783 DOI: 10.1016/j.exger.2016.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 10/18/2016] [Accepted: 10/20/2016] [Indexed: 12/19/2022]
Abstract
Leptin is a key catabolic regulator of food intake (FI) and energy expenditure. Both aging and obesity have been shown to induce leptin-resistance. The present study aimed to analyze age-related changes in the anorexigenic and hypermetabolic responsiveness to acute intracerebroventricular leptin administration in different age-groups of normally fed male Wistar rats (adult and old rats from 3 to 24months of age, NF3 to NF24, respectively). The expressions of the long form of the leptin receptor (Ob-Rb) and inhibitory SOCS3 genes were also assessed by quantitative RT-PCR in the arcuate nucleus (ARC). The influence of high-fat diet-induced obesity (HF) on the anorexigenic leptin effects were also tested in younger and older middle-aged groups (HF6 and HF12). Leptin-induced anorexia varied with age: leptin suppressed re-feeding FI (following 48-h fasting) strongly in young adult (NF3), but not in younger or older middle-aged (NF6 or NF12) or in aging (NF18) rats. However, anorexigenic leptin effects reached statistical significance again in old NF24 rats. Leptin-induced hypermetabolism, on the other hand, showed monotonous age-related decline and disappeared by old age. Ob-Rb expression declined until 12months of age followed by a partial recovery in NF18 and NF24 groups. On the other hand, SOCS3 expression was high in NF6 and NF18 and to some extent in NF24 rats. Age-related alterations of Ob-Rb and SOCS3 expression in the ARC may partly contribute to the explanation of age-related variations in anorexigenic but not hypermetabolic leptin effects. High-fat diet-induced obesity was associated with resistance to leptin-induced anorexia in HF6, similar to that seen in NF6. However, instead of the expected leptin-resistance in HF12, a strong leptin-induced suppression of re-feeding was detected in these obese middle-aged rats. Our results suggest that acute central effects of leptin on anorexia and hypermetabolism change in disparate ways during aging, implying separate mechanisms (e.g. signal transduction pathways) of different leptin actions. The age-related pattern shown by leptin-induced anorexia may contribute to the explanation of middle-aged obesity, and partly to that of aging anorexia. Our findings concerning obese rats are in accord with previous observations on anorexigenic effects of peripherally administered cholecystokinin: diet-induced obesity appeared to accelerate the development of age-related regulatory alterations. Similarly, our present data also raise the possibility that chronic diet-induced obesity promotes responsiveness to centrally applied leptin at least concerning anorexigenic effects.
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Affiliation(s)
- I Rostás
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - J Tenk
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - A Mikó
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - N Füredi
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - S Soós
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - M Solymár
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - A Lengyel
- Department of Biochemistry and Medical Chemistry, University of Pécs, Hungary
| | - M Székely
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - B Gaszner
- Department of Anatomy, Medical School, University of Pecs, Hungary
| | - D Feller
- Department of Pharmaceutical Biotechnology, Medical School, University of Pecs, Hungary
| | - E Pétervári
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary
| | - M Balaskó
- Institute for Translational Medicine, Medical School, University of Pécs, Hungary.
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Correa-Burrows P, Blanco E, Reyes M, Castillo M, Peirano P, Algarín C, Lozoff B, Gahagan S, Burrows R. Leptin status in adolescence is associated with academic performance in high school: a cross-sectional study in a Chilean birth cohort. BMJ Open 2016; 6:e010972. [PMID: 27797980 PMCID: PMC5073574 DOI: 10.1136/bmjopen-2015-010972] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE Leptin is a pleiotropic hormone associated with learning and memory via brain receptors. However, elevated plasma leptin levels may impair cognitive and memory functions. Since individual differences in memory performance affect students' ability to learn, we aimed to study the relation between leptin status in adolescence and school performance. DESIGN AND SETTING We studied 568 adolescents aged 16-17 years from Santiago. A cross-sectional analysis was carried out on a birth cohort conducted in Santiago (Chile). PRIMARY AND SECONDARY OUTCOME MEASURES We measured serum leptin concentration using an enzyme-linked immunosorbent assay. Cut-offs from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study for 16-year-olds were used to define abnormally high leptin levels (hyperleptinaemia). Academic performance was measured using high-school grades and grade point average (GPA). Data were collected in 2009-2012; data analysis was performed in 2014. RESULTS 15% of participants had hyperleptinaemia. They had significantly lower school grades and GPA compared with participants with normal leptin levels (eg, GPA mean difference=33.8 points). Leptin levels were negative and significantly correlated with school grades in 9th, 10th and 12th. Similarly, it was negatively correlated with high-school GPA. After controlling for health, sociodemographic and education confounders, the chances of having a performance ≥75th centile in students having hyperleptinaemia were 32% (95% CI 0.19% to 0.89%) that of students having normal serum leptin concentration. CONCLUSIONS In high school students, abnormally high levels of leptin were associated with poorer academic performance. These findings support the idea of a relationship between leptin and cognition. Further research is needed on the cognitive effects of leptin in younger populations.
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Affiliation(s)
- Paulina Correa-Burrows
- Institute of Nutrition and Food Technology, University of Chile, Santiago de Chile, Santiago, Chile
| | - Estela Blanco
- Child Development and Community Health Division, University of California San Diego, La Jolla, California, USA
| | - Marcela Reyes
- Institute of Nutrition and Food Technology, University of Chile, Santiago de Chile, Santiago, Chile
| | - Marcela Castillo
- Institute of Nutrition and Food Technology, University of Chile, Santiago de Chile, Santiago, Chile
| | - Patricio Peirano
- Institute of Nutrition and Food Technology, University of Chile, Santiago de Chile, Santiago, Chile
| | - Cecilia Algarín
- Institute of Nutrition and Food Technology, University of Chile, Santiago de Chile, Santiago, Chile
| | - Betsy Lozoff
- Center for Human Growth and Development, University of Michigan, Ann Arbor, Michigan, USA
| | - Sheila Gahagan
- Child Development and Community Health Division, University of California San Diego, La Jolla, California, USA
| | - Raquel Burrows
- Institute of Nutrition and Food Technology, University of Chile, Santiago de Chile, Santiago, Chile
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125
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Xu Y, Tong Q. Central leptin action on euglycemia restoration in type 1 diabetes: Restraining responses normally induced by fasting? Int J Biochem Cell Biol 2016; 88:198-203. [PMID: 27702650 DOI: 10.1016/j.biocel.2016.09.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/27/2016] [Accepted: 09/30/2016] [Indexed: 01/29/2023]
Abstract
Leptin monotherapy is sufficient to restore euglycemia in insulinopenic type 1 diabetes (T1D), yet the underlying mechanism remains poorly understood. Accumulating evidence demonstrates that the brain mediates the leptin action on euglycemia restoration. Here, we first review evidence supporting that symptoms in T1D resemble an uncontrolled response to fasting. Then, we discuss recent research progress on brain neurons and their neurotransmitters that potentially mediate the leptin action. Finally, peripheral effective pathways, which are normally involved in fasting responses and associated with leptin action on euglycemia restoration in T1D, will also be discussed. This summary complements several previous excellent reviews on this topic (Meek and Morton, 2016; Perry et al., 2016; Fujikawa and Coppari, 2015). A deep understanding of neurocircuitry and the peripheral effective pathways that mediate the leptin action on euglycemia restoration will likely lead to novel targets for an insulin-independent therapeutics against T1D.
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Affiliation(s)
- Yuanzhong Xu
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, United States
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, United States.
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126
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Pinto-Fochi ME, Pytlowanciv EZ, Reame V, Rafacho A, Ribeiro DL, Taboga SR, Góes RM. A high-fat diet fed during different periods of life impairs steroidogenesis of rat Leydig cells. Reproduction 2016; 152:795-808. [PMID: 27679864 DOI: 10.1530/rep-16-0072] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 09/27/2016] [Indexed: 01/22/2023]
Abstract
This study evaluated the impact of a high-fat diet (HFD) during different stages of rat life, associated or not with maternal obesity, on the content of sex steroid hormones and morphophysiology of Leydig cells. The following periods of development were examined: gestation (O1), gestation and lactation (O2), from weaning to adulthood (O3), from lactation to adulthood (O4), gestation to adulthood (O5), and after sexual maturation (O6). The HFD contained 20% unsaturated fat, whereas the control diet had 4% fat. Maternal obesity was induced by feeding HFD 15 weeks before mating. All HFD groups presented increased body weight, hyperinsulinemia and reduced insulin sensitivity. Except for O1, all HFD groups exhibited a higher adiposity index, hyperleptinemia, reduced testosterone and estradiol testicular levels, and decreased testicular 17β-HSD enzyme . Morphometrical analyses indicated atrophy of Leydig cells in the O2 group. Myelin vesicles were observed in the mitochondrial matrix of Leydig cells in O3, O4, O5 and O6, and autophagosomes containing mitochondria were found in O5 and O6. In conclusion, HFD feeding, before or after sexual maturation, reduces the functional capacity of rat Leydig cells. Maternal obesity associated with HFD during pregnancy/lactation prejudices Leydig cell steroidogenesis and induces its atrophy in adulthood, even if it is replaced by a conventional diet at later stages of life. Regardless of the life period of exposure to HFD, deregulation of leptin is the main factor related to steroidogenic impairment of Leydig cells, and, in groups exposed for longer periods (O3, O4, O5 and O6), this is worsened by structural damage and mitochondrial degeneration of these cells.
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Affiliation(s)
- Maria Etelvina Pinto-Fochi
- Department of BiologyInstitute of Biosciences, Letters and Exact Sciences, Univ Estadual Paulista - IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil
| | - Eloísa Zanin Pytlowanciv
- Department of BiologyInstitute of Biosciences, Letters and Exact Sciences, Univ Estadual Paulista - IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil.,Department of Structural and Functional BiologyInstitute of Biology, State University of Campinas, IB/UNICAMP, Campinas, São Paulo, Brazil
| | - Vanessa Reame
- Department of BiologyInstitute of Biosciences, Letters and Exact Sciences, Univ Estadual Paulista - IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil
| | - Alex Rafacho
- Department of Physiological SciencesFederal University of Santa Catarina, UFSC, Florianópolis, Santa Catarina, Brazil
| | - Daniele Lisboa Ribeiro
- Department of Histology- ICBIMFederal University of Uberlandia, Uberlândia, Minas Gerais, Brazil
| | - Sebastião Roberto Taboga
- Department of BiologyInstitute of Biosciences, Letters and Exact Sciences, Univ Estadual Paulista - IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil.,Department of Structural and Functional BiologyInstitute of Biology, State University of Campinas, IB/UNICAMP, Campinas, São Paulo, Brazil
| | - Rejane Maira Góes
- Department of BiologyInstitute of Biosciences, Letters and Exact Sciences, Univ Estadual Paulista - IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil .,Department of Structural and Functional BiologyInstitute of Biology, State University of Campinas, IB/UNICAMP, Campinas, São Paulo, Brazil
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Karimi K, Lindgren TH, Koch CA, Brodell RT. Obesity as a risk factor for malignant melanoma and non-melanoma skin cancer. Rev Endocr Metab Disord 2016; 17:389-403. [PMID: 27832418 DOI: 10.1007/s11154-016-9393-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The dramatic increases in incidence of both obesity and many cancers including skin cancer emphasize the need to better understand the pathophysiology of both conditions and their connections. Melanoma is considered the fastest growing cancer and rates of non-melanoma skin cancer have also increased over the last decade. The molecular mechanisms underlying the association between obesity and skin cancer are not clearly understood but emerging evidence points to changes in the tumor microenvironment including aberrant cell signaling and genomic instability in the chronic inflammatory state many obese individuals experience. This article reviews the literature linking obesity to melanoma and non-melanoma skin cancer.
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Affiliation(s)
- K Karimi
- School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - T H Lindgren
- School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - C A Koch
- Division of Endocrinology, University of Mississippi Medical Center, Jackson, MS, USA
- Cancer Institute, University of Mississippi Medical Center, Jackson, MS, USA
- G.V. (Sonny) Montgomery VA Medical Center, Jackson, MS, USA
| | - Robert T Brodell
- Department of Dermatology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA.
- Department of Pathology, University of Mississippi Medical Center, Jackson, MS, USA.
- Department of Dermatology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
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128
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Suman S, Kumar S, Fornace AJ, Datta K. Space radiation exposure persistently increased leptin and IGF1 in serum and activated leptin-IGF1 signaling axis in mouse intestine. Sci Rep 2016; 6:31853. [PMID: 27558773 PMCID: PMC4997262 DOI: 10.1038/srep31853] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 07/28/2016] [Indexed: 12/21/2022] Open
Abstract
Travel into outer space is fraught with risk of exposure to energetic heavy ion radiation such as 56Fe ions, which due to its high linear energy transfer (high-LET) characteristics deposits higher energy per unit volume of tissue traversed and thus more damaging to cells relative to low-LET radiation such as γ rays. However, estimates of human health risk from energetic heavy ion exposure are hampered due to lack of tissue specific in vivo molecular data. We investigated long-term effects of 56Fe radiation on adipokines and insulin-like growth factor 1 (IGF1) signaling axis in mouse intestine and colon. Six- to eight-week-old C57BL/6J mice were exposed to 1.6 Gy of 56Fe ions. Serum and tissues were collected up to twelve months post-irradiation. Serum was analyzed for leptin, adiponectin, IGF1, and IGF binding protein 3. Receptor expressions and downstream signaling pathway alterations were studied in tissues. Irradiation increased leptin and IGF1 levels in serum, and IGF1R and leptin receptor expression in tissues. When considered along with upregulated Jak2/Stat3 pathways and cell proliferation, our data supports the notion that space radiation exposure is a risk to endocrine alterations with implications for chronic pathophysiologic changes in gastrointestinal tract.
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Affiliation(s)
- Shubhankar Suman
- Department of Biochemistry and Molecular &Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA
| | - Santosh Kumar
- Department of Biochemistry and Molecular &Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA
| | - Albert J Fornace
- Department of Biochemistry and Molecular &Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA.,Center of Excellence in Genomic Medicine Research (CEGMR), King Abdulaziz University, Jeddah, Saudi Arabia
| | - Kamal Datta
- Department of Biochemistry and Molecular &Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA
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Pfalzer AC, Kamanu FK, Parnell LD, Tai AK, Liu Z, Mason JB, Crott JW. Interactions between the colonic transcriptome, metabolome, and microbiome in mouse models of obesity-induced intestinal cancer. Physiol Genomics 2016; 48:545-53. [DOI: 10.1152/physiolgenomics.00034.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/15/2016] [Indexed: 12/31/2022] Open
Abstract
Obesity is a significant risk factor for colorectal cancer (CRC); however, the relative contribution of high-fat (HF) consumption and excess adiposity remains unclear. It is becoming apparent that obesity perturbs both the intestinal microbiome and metabolome, and each has the potential to induce protumorigenic changes in the epithelial transcriptome. The physiological consequences and the degree to which these different biologic systems interact remain poorly defined. To understand the mechanisms by which obesity drives colonic tumorigenesis, we profiled the colonic epithelial transcriptome of HF-fed and genetically obese (DbDb) mice with a genetic predisposition to intestinal tumorigenesis (Apc1638N); 266 and 584 genes were differentially expressed in the colonic mucosa of HF and DbDb mice, respectively. These genes mapped to pathways involved in immune function, and cellular proliferation and cancer. Furthermore, Akt was central within the networks of interacting genes identified in both gene sets. Regression analyses of coexpressed genes with the abundance of bacterial taxa identified three taxa, previously correlated with tumor burden, to be significantly correlated with a gene module enriched for Akt-related genes. Similarly, regression of coexpressed genes with metabolites found that adenosine, which was negatively associated with inflammatory markers and tumor burden, was also correlated with a gene module enriched with Akt regulators. Our findings provide evidence that HF consumption and excess adiposity result in changes in the colonic transcriptome that, although distinct, both appear to converge on Akt signaling. Such changes could be mediated by alterations in the colonic microbiome and metabolome.
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Affiliation(s)
- Anna C. Pfalzer
- Cancer Cluster, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Vitamins and Carcinogenesis Laboratory, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts
| | - Frederick K. Kamanu
- Nutrition and Genomics Laboratory, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
| | - Laurence D. Parnell
- Cancer Cluster, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Agricultural Research Service, USDA, Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
| | - Albert K. Tai
- Genomics Core, Tufts University School of Medicine, Boston, Massachusetts; and
| | - Zhenhua Liu
- Cancer Cluster, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- School of Public Health and Health Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Joel B. Mason
- Cancer Cluster, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Vitamins and Carcinogenesis Laboratory, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts
| | - Jimmy W. Crott
- Cancer Cluster, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Vitamins and Carcinogenesis Laboratory, USDA Jean Mayer Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts
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130
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Varela-Rodríguez BM, Pena-Bello L, Juiz-Valiña P, Vidal-Bretal B, Cordido F, Sangiao-Alvarellos S. FNDC5 expression and circulating irisin levels are modified by diet and hormonal conditions in hypothalamus, adipose tissue and muscle. Sci Rep 2016; 6:29898. [PMID: 27432282 PMCID: PMC4949437 DOI: 10.1038/srep29898] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/22/2016] [Indexed: 02/06/2023] Open
Abstract
Irisin is processed from fibronectin type III domain-containing protein 5 (FNDC5). However, a controversy exists concerning irisin origin, regulation and function. To elucidate the relationship between serum irisin and FNDC5 mRNA expression levels, we evaluated plasma irisin levels and FNDC5 gene expression in the hypothalamus, gastrocnemius muscle and different depots of adipose tissue in models of altered metabolism. In normal rats, blood irisin levels diminished after 48-h fast and with leptin, insulin and alloxan treatments, and serum irisin concentrations increased in diabetic rats after insulin treatment and acute treatments of irisin increased blood insulin levels. No changes were observed during long-term experiments with different diets. We suggested that levels of circulating irisin are the result of the sum of the irisin produced by different depots of adipose tissue and skeletal muscle. This study shows for the first time that there are differences in FNDC5 expression depending on white adipose tissue depots. Moreover, a considerable decrease in visceral and epididymal adipose tissue depots correlated with increased FNDC5 mRNA expression levels, probably in an attempt to compensate the decrease that occurs in their mass. Hypothalamic FNDC5 expression did not change for any of the tested diets but increased with leptin, insulin and metformin treatments suggesting that the regulation of central and peripheral FNDC5/irisin expression and functions are different.
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Affiliation(s)
- B. M. Varela-Rodríguez
- Department of Medicine, School of Health Science, University of A Coruña, Campus de Oza, 15006, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Xubias de Arriba, 84. 15006, A Coruña, Spain
| | - L. Pena-Bello
- Department of Medicine, School of Health Science, University of A Coruña, Campus de Oza, 15006, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Xubias de Arriba, 84. 15006, A Coruña, Spain
- Division of endocrinology, Complexo Hospitalario Universitario de A Coruña (CHUAC), 15006 A Coruña, Spain
| | - P. Juiz-Valiña
- Department of Medicine, School of Health Science, University of A Coruña, Campus de Oza, 15006, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Xubias de Arriba, 84. 15006, A Coruña, Spain
| | - B. Vidal-Bretal
- Department of Medicine, School of Health Science, University of A Coruña, Campus de Oza, 15006, Spain
| | - F. Cordido
- Department of Medicine, School of Health Science, University of A Coruña, Campus de Oza, 15006, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Xubias de Arriba, 84. 15006, A Coruña, Spain
- Division of endocrinology, Complexo Hospitalario Universitario de A Coruña (CHUAC), 15006 A Coruña, Spain
| | - S. Sangiao-Alvarellos
- Department of Medicine, School of Health Science, University of A Coruña, Campus de Oza, 15006, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Xubias de Arriba, 84. 15006, A Coruña, Spain
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Alliouachene S, Bilanges B, Chaussade C, Pearce W, Foukas LC, Scudamore CL, Moniz LS, Vanhaesebroeck B. Inactivation of class II PI3K-C2α induces leptin resistance, age-dependent insulin resistance and obesity in male mice. Diabetologia 2016; 59:1503-1512. [PMID: 27138914 PMCID: PMC4901096 DOI: 10.1007/s00125-016-3963-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 03/24/2016] [Indexed: 01/08/2023]
Abstract
AIMS/HYPOTHESIS While the class I phosphoinositide 3-kinases (PI3Ks) are well-documented positive regulators of metabolism, the involvement of class II PI3K isoforms (PI3K-C2α, -C2β and -C2γ) in metabolic regulation is just emerging. Organismal inactivation of PI3K-C2β increases insulin signalling and sensitivity, whereas PI3K-C2γ inactivation has a negative metabolic impact. In contrast, the role of PI3K-C2α in organismal metabolism remains unexplored. In this study, we investigated whether kinase inactivation of PI3K-C2α affects glucose metabolism in mice. METHODS We have generated and characterised a mouse line with a constitutive inactivating knock-in (KI) mutation in the kinase domain of the gene encoding PI3K-C2α (Pik3c2a). RESULTS While homozygosity for kinase-dead PI3K-C2α was embryonic lethal, heterozygous PI3K-C2α KI mice were viable and fertile, with no significant histopathological findings. However, male heterozygous mice showed early onset leptin resistance, with a defect in leptin signalling in the hypothalamus, correlating with a mild, age-dependent obesity, insulin resistance and glucose intolerance. Insulin signalling was unaffected in insulin target tissues of PI3K-C2α KI mice, in contrast to previous reports in which downregulation of PI3K-C2α in cell lines was shown to dampen insulin signalling. Interestingly, no metabolic phenotypes were detected in female PI3K-C2α KI mice at any age. CONCLUSIONS/INTERPRETATION Our data uncover a sex-dependent role for PI3K-C2α in the modulation of hypothalamic leptin action and systemic glucose homeostasis. ACCESS TO RESEARCH MATERIALS All reagents are available upon request.
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Affiliation(s)
- Samira Alliouachene
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
| | - Benoit Bilanges
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
| | - Claire Chaussade
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK
- Galderma R&D, Sophia Antipolis Cedex, France
| | - Wayne Pearce
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK
| | - Lazaros C Foukas
- Institute of Healthy Ageing and Department of Genetics, Evolution and Environment, University College London, London, UK
| | - Cheryl L Scudamore
- Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, Harwell, UK
| | - Larissa S Moniz
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK
| | - Bart Vanhaesebroeck
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
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132
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Harpsøe MC, Nielsen NM, Friis-Møller N, Andersson M, Wohlfahrt J, Linneberg A, Nohr EA, Jess T. Body Mass Index and Risk of Infections Among Women in the Danish National Birth Cohort. Am J Epidemiol 2016; 183:1008-17. [PMID: 27188940 DOI: 10.1093/aje/kwv300] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 10/23/2015] [Indexed: 12/14/2022] Open
Abstract
We investigated the possible association between body mass index (BMI; weight (kg)/height (m)(2)) and hospitalization or treatment for acute infection in a prospective cohort study. We linked 75,001 women enrolled in the Danish National Birth Cohort from 1996 to 2002, who had information on BMI and a broad range of confounders, to data on infectious diseases and use of antimicrobial agents from the National Patient Register and the Danish Prescription Register. Associations were tested using Cox proportional hazards models. During 12 years of follow-up, we observed a U-shaped association between baseline BMI and later hospitalization for 1) any infectious disease and 2) infections of the respiratory tract, whereas a dose-response relationship was seen for skin infections. The most pronounced associations were seen for acute upper respiratory infections at multiple and unspecified sites (underweight (BMI <18.5): hazard ratio (HR) = 4.26, 95% confidence interval (CI): 1.69, 10.7; obesity (BMI ≥30): HR = 3.64, 95% CI: 1.62, 8.18), erysipelas (obesity: HR = 5.19, 95% CI: 3.38, 7.95), and fungal infections (underweight: HR = 3.19, 95% CI: 1.53, 6.66). Slightly greater use of antimicrobials was observed among overweight (BMI 25-<30; HR = 1.08, 95% CI: 1.06, 1.10) and obese (HR = 1.21, 95% CI: 1.17, 1.24) women. Among Danish women, underweight and obesity were associated with increased risk of community-acquired infectious diseases, especially infections of the upper respiratory tract and skin.
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133
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Mascali A, Franzese O, Nisticò S, Campia U, Lauro D, Cardillo C, Di Daniele N, Tesauro M. Obesity and kidney disease: Beyond the hyperfiltration. Int J Immunopathol Pharmacol 2016; 29:354-63. [PMID: 27044633 DOI: 10.1177/0394632016643550] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 02/23/2016] [Indexed: 01/13/2023] Open
Abstract
In industrialized countries, overweight and obesity account for approximately 13.8% and 24.9% of the kidney disease observed in men and women, respectively. Moreover, obesity-associated glomerulopathy is now considered as "an emerging epidemic." Kidney function can be negatively impacted by obesity through several mechanisms, either direct or indirect. While it is well established that obesity represents the leading risk factor for type 2 diabetes and hypertension, awareness that obesity is associated with direct kidney damage independently of hypertension and diabetes is still not widespread. In this paper we will discuss the emerging role of adipose tissue, particularly in the visceral depot, in obesity-induced chronic kidney damage.
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Affiliation(s)
- A Mascali
- Division of Hypertension and Nephrology, Department of System Medicine, University of Rome Tor Vergata, Rome, Italy
| | - O Franzese
- Division of Hypertension and Nephrology, Department of System Medicine, University of Rome Tor Vergata, Rome, Italy
| | - S Nisticò
- Department of Health Sciences, University of Catanzaro "Magna Graecia", Catanzaro, Italy
| | - U Campia
- MedStar Cardiovascular Research Network, Washington, DC, USA
| | - D Lauro
- Endocrinology Unit, University of Rome Tor Vergata, Rome, Italy
| | - C Cardillo
- Internal Medicine, Catholic University, Rome, Italy
| | - N Di Daniele
- Division of Hypertension and Nephrology, Department of System Medicine, University of Rome Tor Vergata, Rome, Italy
| | - M Tesauro
- Division of Hypertension and Nephrology, Department of System Medicine, University of Rome Tor Vergata, Rome, Italy
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134
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Xu Y, Chang JT, Myers MG, Xu Y, Tong Q. Euglycemia Restoration by Central Leptin in Type 1 Diabetes Requires STAT3 Signaling but Not Fast-Acting Neurotransmitter Release. Diabetes 2016; 65:1040-9. [PMID: 26822087 PMCID: PMC4806656 DOI: 10.2337/db15-1160] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 01/13/2016] [Indexed: 12/21/2022]
Abstract
Central leptin action is sufficient to restore euglycemia in insulinopenic type 1 diabetes (T1D); however, the underlying mechanism remains poorly understood. To examine the role of intracellular signal transducer and activator of transcription 3 (STAT3) pathways, we used LepRs/s mice with disrupted leptin-phosphorylated STAT3 signaling to test the effect of central leptin on euglycemia restoration. These mice developed streptozocin-induced T1D, which was surprisingly not associated with hyperglucagonemia, a typical manifestation in T1D. Further, leptin action on euglycemia restoration was abrogated in these mice, which was associated with refractory hypercorticosteronemia. To examine the role of fast-acting neurotransmitters glutamate and γ-aminobutyric acid (GABA), two major neurotransmitters in the brain, from leptin receptor (LepR) neurons, we used mice with disrupted release of glutamate, GABA, or both from LepR neurons. Surprisingly, all mice responded normally to leptin-mediated euglycemia restoration, which was associated with expected correction from hyperglucagonemia and hyperphagia. In contrast, mice with loss of glutamate and GABA appeared to develop an additive obesity effect over those with loss of single neurotransmitter release. Thus, our study reveals that STAT3 signaling, but not fast-acting neurotransmitter release, is required for leptin action on euglycemia restoration and that hyperglucagonemia is not required for T1D.
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Affiliation(s)
- Yuanzhong Xu
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX
| | - Jeffrey T Chang
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX Department of Integrative Biology and Pharmacology of McGovern Medical School and School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX
| | - Martin G Myers
- Departments of Internal Medicine and Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases of McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX
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135
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Bassi M, Furuya WI, Zoccal DB, Menani JV, Colombari DSA, Mulkey DK, Colombari E. Facilitation of breathing by leptin effects in the central nervous system. J Physiol 2016; 594:1617-25. [PMID: 26095748 PMCID: PMC4799963 DOI: 10.1113/jp270308] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 05/13/2015] [Indexed: 01/01/2023] Open
Abstract
With the global epidemic of obesity, breathing disorders associated with excess body weight have markedly increased. Respiratory dysfunctions caused by obesity were originally attributed to mechanical factors; however, recent studies have suggested a pathophysiological component that involves the central nervous system (CNS) and hormones such as leptin produced by adipocytes as well as other cells. Leptin is suggested to stimulate breathing and leptin deficiency causes an impairment of the chemoreflex, which can be reverted by leptin therapy. This facilitation of the chemoreflex may depend on the action of leptin in the hindbrain areas involved in the respiratory control such as the nucleus of the solitary tract (NTS), a site that receives chemosensory afferents, and the ventral surface of the medulla that includes the retrotrapezoid nucleus (RTN), a central chemosensitive area, and the rostral ventrolateral medulla (RVLM). Although the mechanisms and pathways activated by leptin to facilitate breathing are still not completely clear, evidence suggests that the facilitatory effects of leptin on breathing require the brain melanocortin system, including the POMC-MC4R pathway, a mechanism also activated by leptin to modulate blood pressure. The results of all the studies that have investigated the effect of leptin on breathing suggest that disruption of leptin signalling as caused by obesity-induced reduction of central leptin function (leptin resistance) is a relevant mechanism that may contribute to respiratory dysfunctions associated with obesity.
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Affiliation(s)
- M. Bassi
- Department of Physiology and Pathology, School of DentistrySão Paulo State University (UNESP)AraraquaraSPBrazil
| | - W. I. Furuya
- Department of Physiology and Pathology, School of DentistrySão Paulo State University (UNESP)AraraquaraSPBrazil
| | - D. B. Zoccal
- Department of Physiology and Pathology, School of DentistrySão Paulo State University (UNESP)AraraquaraSPBrazil
| | - J. V. Menani
- Department of Physiology and Pathology, School of DentistrySão Paulo State University (UNESP)AraraquaraSPBrazil
| | - D. S. A. Colombari
- Department of Physiology and Pathology, School of DentistrySão Paulo State University (UNESP)AraraquaraSPBrazil
| | - D. K. Mulkey
- Department of Physiology and NeurobiologyUniversity of ConnecticutStorrsCTUSA
| | - E. Colombari
- Department of Physiology and Pathology, School of DentistrySão Paulo State University (UNESP)AraraquaraSPBrazil
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Jing Y, Cai X, Xu Y, Zhu C, Wang L, Wang S, Zhu X, Gao P, Zhang Y, Jiang Q, Shu G. α-Lipoic Acids Promote the Protein Synthesis of C2C12 Myotubes by the TLR2/PI3K Signaling Pathway. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:1720-1729. [PMID: 26855124 DOI: 10.1021/acs.jafc.5b05952] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Skeletal muscle protein turnover is regulated by endocrine hormones, nutrients, and inflammation. α-Lipoic acid (ALA) plays an important role in energy homeostasis. Therefore, the aim of this study was to investigate the effects of ALA on protein synthesis in skeletal muscles and reveal the underlying mechanism. ALA (25 μM) significantly increased the protein synthesis and phosphorylation of Akt, mTOR, and S6 in C2C12 myotubes with attenuated phosphorylation of AMPK, Ikkα/β, and eIF2α. Intraperitoneal injection of 50 mg/kg ALA also produced the same results in mouse gastrocnemius. Both the PI3K (LY294002) and mTOR (rapamycin) inhibitors abolished the effects of ALA on protein synthesis in the C2C12 myotubes. However, AICAR (AMPK agonist) failed to block the activation of mTOR and S6 by ALA. ALA increased TLR2 and MyD88 mRNA expression in the C2C12 myotubes. TLR2 knockdown by siRNA almost eliminated the effects of ALA on protein synthesis and the Akt/mTOR pathway in the C2C12 myotubes. Immunoprecipitation data showed that ALA enhanced the p85 subunit of PI3K binding to MyD88. These findings indicate that ALA induces protein synthesis and the PI3K/Akt signaling pathway by TLR2.
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Affiliation(s)
- Yuanyuan Jing
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Xingcai Cai
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Yaqiong Xu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Canjun Zhu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Lina Wang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Songbo Wang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Xiaotong Zhu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Ping Gao
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Yongliang Zhang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Qingyan Jiang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
| | - Gang Shu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University , Guangzhou 510640, Guangdong, China
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Asperdichrome, an unusual dimer of tetrahydroxanthone through an ether bond, with protein tyrosine phosphatase 1B inhibitory activity, from the Okinawan freshwater Aspergillus sp. TPU1343. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2015.12.111] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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138
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Paleczny B, Siennicka A, Zacharski M, Jankowska EA, Ponikowska B, Ponikowski P. Increased body fat is associated with potentiation of blood pressure response to hypoxia in healthy men: relations with insulin and leptin. Clin Auton Res 2016; 26:107-16. [PMID: 26781642 PMCID: PMC4819928 DOI: 10.1007/s10286-015-0338-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/16/2015] [Indexed: 12/18/2022]
Abstract
Background Increased peripheral chemosensitivity (PChS) has been proposed
as mechanism underlying obesity-related sympathoactivation, with insulin and/or leptin as possible mediators. However, human data on PChS in obesity are scarce. Therefore, we explored this issue in a sample of 41 healthy men aged 30–59 years, divided according to body fat percentage (fat %) into two groups: <25 and ≥25 %. Methods PChS was assessed using transient hypoxia method [respiratory (PChS-MV), heart rate (PChS-HR), and blood pressure (PChS-SBP) responses were calculated]. Baroreflex sensitivity (BRS-Seq) was assessed using sequence method. Fasting plasma insulin and leptin levels were measured. Homeostatic model assessment (HOMA) was used to assess insulin sensitivity/resistance. Results Individuals with ≥25 % body fat demonstrated increased PChS-SBP (p < 0.01), but unchanged PChS-MV and PChS-HR (both p > 0.4). PChS-SBP was related positively with anthropometric characteristics (e.g. waist circumference, fat %), plasma insulin and HOMA (all p < 0.05), and negatively with BRS-Seq (p = 0.001), but not with plasma leptin (p = 0.27). Conclusions In healthy men, overweight/obesity is accompanied by augmented blood pressure response from peripheral chemoreceptors, while respiratory and heart rate responses remain unaltered. Hyperinsulinaemia and insulin resistance (but not hyperleptinaemia) are associated with augmented pressure response from chemoreceptors. Electronic supplementary material The online version of this article (doi:10.1007/s10286-015-0338-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bartłomiej Paleczny
- Department of Physiology, Wroclaw Medical University, ul. Chałubińskiego 10, 50-368, Wroclaw, Poland. .,Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland.
| | - Agnieszka Siennicka
- Department of Physiology, Wroclaw Medical University, ul. Chałubińskiego 10, 50-368, Wroclaw, Poland.,Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland
| | - Maciej Zacharski
- Department of Biochemistry, Pharmacology and Toxicology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
| | - Ewa Anita Jankowska
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland.,Laboratory for Applied Research on Cardiovascular System, Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Beata Ponikowska
- Department of Physiology, Wroclaw Medical University, ul. Chałubińskiego 10, 50-368, Wroclaw, Poland
| | - Piotr Ponikowski
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland.,Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
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A dimeric urea of the bisabolene sesquiterpene from the Okinawan marine sponge Axinyssa sp. inhibits protein tyrosine phosphatase 1B activity in Huh-7 human hepatoma cells. Bioorg Med Chem Lett 2016; 26:315-317. [DOI: 10.1016/j.bmcl.2015.12.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/02/2015] [Accepted: 12/08/2015] [Indexed: 11/19/2022]
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140
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Morishima T, Goto K. Ghrelin, GLP-1, and leptin responses during exposure to moderate hypoxia. Appl Physiol Nutr Metab 2015; 41:375-81. [PMID: 26863323 DOI: 10.1139/apnm-2015-0311] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Severe hypoxia has been indicated to cause acute changes in appetite-related hormones, which attenuate perceived appetite. However, the effects of moderate hypoxia on appetite-related hormonal regulation and perceived appetite have not been elucidated. Therefore, we examined the effects of moderate hypoxia on appetite-related hormonal regulation and perceived appetite. Eight healthy males (21.0 ± 0.6 years; 173 ± 2.3 cm; 70.6 ± 5.0 kg; 23.4 ± 1.1 kg/m(2)) completed two experimental trials on separate days: a rest trial in normoxia (FiO2 = 20.9%) and a rest trial in hypoxia (FiO2 = 15.0%). The experimental trials were performed over 7 h in an environmental chamber. Blood samples and scores of subjective appetite were collected over 7 h. Standard meals were provided 1 h (745 kcal) and 4 h (731 kcal) after initiating exposure to hypoxia or normoxia within the chamber. Although each meal significantly reduced plasma active ghrelin concentrations (P < 0.05), the response did not differ significantly between the trials over 7 h. No significant differences in the area under the curves for plasma active ghrelin concentrations over 7 h were observed between the two trials. No significant differences were observed in glucagon-like peptide 1 or leptin concentrations over 7 h between the trials. The subjective feeling of hunger and fullness acutely changed in response to meal ingestions. However, these responses were not affected by exposure to moderate hypoxia. In conclusion, 7 h of exposure to moderate hypoxia did not change appetite-related hormonal responses or perceived appetite in healthy males.
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Affiliation(s)
- Takuma Morishima
- a Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1, Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.,b Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083, Japan
| | - Kazushige Goto
- a Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1, Nojihigashi, Kusatsu, Shiga, 525-8577, Japan
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Turner RT, Dube M, Branscum AJ, Wong CP, Olson DA, Zhong X, Kweh MF, Larkin IV, Wronski TJ, Rosen CJ, Kalra SP, Iwaniec UT. Hypothalamic leptin gene therapy reduces body weight without accelerating age-related bone loss. J Endocrinol 2015; 227:129-41. [PMID: 26487675 PMCID: PMC4917201 DOI: 10.1530/joe-15-0280] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/14/2015] [Indexed: 02/04/2023]
Abstract
Excessive weight gain in adults is associated with a variety of negative health outcomes. Unfortunately, dieting, exercise, and pharmacological interventions have had limited long-term success in weight control and can result in detrimental side effects, including accelerating age-related cancellous bone loss. We investigated the efficacy of using hypothalamic leptin gene therapy as an alternative method for reducing weight in skeletally-mature (9 months old) female rats and determined the impact of leptin-induced weight loss on bone mass, density, and microarchitecture, and serum biomarkers of bone turnover (CTx and osteocalcin). Rats were implanted with cannulae in the 3rd ventricle of the hypothalamus and injected with either recombinant adeno-associated virus encoding the gene for rat leptin (rAAV-Leptin, n=7) or a control vector encoding green fluorescent protein (rAAV-GFP, n=10) and sacrificed 18 weeks later. A baseline control group (n=7) was sacrificed at vector administration. rAAV-Leptin-treated rats lost weight (-4±2%) while rAAV-GFP-treated rats gained weight (14±2%) during the study. At study termination, rAAV-Leptin-treated rats weighed 17% less than rAAV-GFP-treated rats and had lower abdominal white adipose tissue weight (-80%), serum leptin (-77%), and serum IGF1 (-34%). Cancellous bone volume fraction in distal femur metaphysis and epiphysis, and in lumbar vertebra tended to be lower (P<0.1) in rAAV-GFP-treated rats (13.5 months old) compared to baseline control rats (9 months old). Significant differences in cancellous bone or biomarkers of bone turnover were not detected between rAAV-Leptin and rAAV-GFP rats. In summary, rAAV-Leptin-treated rats maintained a lower body weight compared to baseline and rAAV-GFP-treated rats with minimal effects on bone mass, density, microarchitecture, or biochemical markers of bone turnover.
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Affiliation(s)
- Russell T Turner
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Michael Dube
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Adam J Branscum
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Carmen P Wong
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Dawn A Olson
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Xiaoying Zhong
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Mercedes F Kweh
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Iske V Larkin
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Thomas J Wronski
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Clifford J Rosen
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Satya P Kalra
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
| | - Urszula T Iwaniec
- Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA Skeletal Biology LaboratorySchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon 97331, USACenter for Healthy Aging ResearchOregon State University, Corvallis, Oregon, USADepartment of NeuroscienceMcKnight Brain Institute, University of Florida, Gainesville, Florida, USABiostatisticsSchool of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USADepartment of Physiological SciencesUniversity of Florida, Gainesville, Florida, USADepartment of Large Animal Clinical SciencesUniversity of Florida, Gainesville, Florida, USAMaine Medical Center Research InstituteScarborough, Maine, USA
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Akter R, Cao P, Noor H, Ridgway Z, Tu LH, Wang H, Wong AG, Zhang X, Abedini A, Schmidt AM, Raleigh DP. Islet Amyloid Polypeptide: Structure, Function, and Pathophysiology. J Diabetes Res 2015; 2016:2798269. [PMID: 26649319 PMCID: PMC4662979 DOI: 10.1155/2016/2798269] [Citation(s) in RCA: 156] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 04/24/2015] [Indexed: 01/29/2023] Open
Abstract
The hormone islet amyloid polypeptide (IAPP, or amylin) plays a role in glucose homeostasis but aggregates to form islet amyloid in type-2 diabetes. Islet amyloid formation contributes to β-cell dysfunction and death in the disease and to the failure of islet transplants. Recent work suggests a role for IAPP aggregation in cardiovascular complications of type-2 diabetes and hints at a possible role in type-1 diabetes. The mechanisms of IAPP amyloid formation in vivo or in vitro are not understood and the mechanisms of IAPP induced β-cell death are not fully defined. Activation of the inflammasome, defects in autophagy, ER stress, generation of reactive oxygen species, membrane disruption, and receptor mediated mechanisms have all been proposed to play a role. Open questions in the field include the relative importance of the various mechanisms of β-cell death, the relevance of reductionist biophysical studies to the situation in vivo, the molecular mechanism of amyloid formation in vitro and in vivo, the factors which trigger amyloid formation in type-2 diabetes, the potential role of IAPP in type-1 diabetes, the development of clinically relevant inhibitors of islet amyloidosis toxicity, and the design of soluble, bioactive variants of IAPP for use as adjuncts to insulin therapy.
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Affiliation(s)
- Rehana Akter
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Ping Cao
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Harris Noor
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Zachary Ridgway
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Ling-Hsien Tu
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Hui Wang
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Amy G. Wong
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Xiaoxue Zhang
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Andisheh Abedini
- Diabetes Research Program, NYU School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Ann Marie Schmidt
- Diabetes Research Program, NYU School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Daniel P. Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
- Research Department of Structural and Molecule Biology, University College London, Gower Street, London WC1E 6BT, UK
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143
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Weigt C, Hertrampf T, Flenker U, Hülsemann F, Kurnaz P, Fritzemeier KH, Diel P. Effects of estradiol, estrogen receptor subtype-selective agonists and genistein on glucose metabolism in leptin resistant female Zucker diabetic fatty (ZDF) rats. J Steroid Biochem Mol Biol 2015; 154:12-22. [PMID: 26134426 DOI: 10.1016/j.jsbmb.2015.06.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 06/19/2015] [Accepted: 06/22/2015] [Indexed: 01/22/2023]
Abstract
The leptin resistant Zucker diabetic fatty (ZDF) rats are hyperphagic and become obese, but whereas the males develop type 2 diabetes mellitus (T2DM), the females remain euglycaemic. As estrogen deficiency is known to increase the risk of developing T2DM, we evaluated the role of ER subtypes alpha and beta in the development of glucose tolerance in leptin resistant ovariectomized (OVX) ZDF rats. At least six rats per group were treated with either vehicle (OVX), 17β-estradiol (E2), ER subtype-selective agonists (Alpha and Beta), or genistein (Gen) for 17 weeks. At the end of the treatment period a glucose tolerance assay was performed and the metabolic flux of (13)C-glucose for the E2 group was investigated. OVX ZDF rats treated with E2, Alpha, Beta, and Gen tolerated the glucose significantly better than untreated controls. E2 treatment increased absorbance/flux of (13)C-glucose to metabolic relevant tissues such liver, adipose tissue, gastrocnemius, and soleus muscle. Moreover, whereas Alpha treatment markedly increased mRNA expression of GLUT4 in gastrocnemius muscle, Beta treatment resulted in the largest fiber sizes of the soleus muscle. Treatment with Gen increased both the mRNA expression of GLUT 4 and the fiber sizes in the skeletal muscle. In addition, E2 and Alpha treatment decreased food intake and body weight gain. In summary, estrogen-improved glucose absorption is mediated via different molecular mechanisms: while activation of ER alpha seems to stimulate muscular GLUT4 functionality, activation of ER beta results in a hypertrophy of muscle fibers. In addition, selective activation of ER alpha decreased food intake and body weight gain. Our data further indicate that ER subtype-selective agonists and genistein improve systemic glucose tolerance also in the absence of a functional leptin signaling pathway.
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Affiliation(s)
- Carmen Weigt
- German Sports University Cologne, Institute of Cardiovascular Research and Sports Medicine, Department of Cellular and Molecular Sports Medicine, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.
| | - Torsten Hertrampf
- German Sports University Cologne, Institute of Cardiovascular Research and Sports Medicine, Department of Cellular and Molecular Sports Medicine, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.
| | - Ulrich Flenker
- German Sports University Cologne, Institute of Biochemistry, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.
| | - Frank Hülsemann
- German Sports University Cologne, Institute of Biochemistry, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.
| | - Pinar Kurnaz
- German Sports University Cologne, Institute of Cardiovascular Research and Sports Medicine, Department of Cellular and Molecular Sports Medicine, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.
| | | | - Patrick Diel
- German Sports University Cologne, Institute of Cardiovascular Research and Sports Medicine, Department of Cellular and Molecular Sports Medicine, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.
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Chang WC, Kuo PL, Chen CW, Wu JSB, Shen SC. Caffeic acid improves memory impairment and brain glucose metabolism via ameliorating cerebral insulin and leptin signaling pathways in high-fat diet-induced hyperinsulinemic rats. Food Res Int 2015. [DOI: 10.1016/j.foodres.2015.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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145
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Altered gut and adipose tissue hormones in overweight and obese individuals: cause or consequence? Int J Obes (Lond) 2015; 40:622-32. [PMID: 26499438 PMCID: PMC4827002 DOI: 10.1038/ijo.2015.220] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 08/07/2015] [Accepted: 09/02/2015] [Indexed: 12/11/2022]
Abstract
The aim of this article is to review the research into the main peripheral appetite signals altered in human obesity, together with their modifications after body weight loss with diet and exercise and after bariatric surgery, which may be relevant to strategies for obesity treatment. Body weight homeostasis involves the gut–brain axis, a complex and highly coordinated system of peripheral appetite hormones and centrally mediated neuronal regulation. The list of peripheral anorexigenic and orexigenic physiological factors in both animals and humans is intimidating and expanding, but anorexigenic glucagon-like peptide 1 (GLP-1), cholecystokinin (CCK), peptide YY (PYY) and orexigenic ghrelin from the gastrointestinal tract, pancreatic polypeptide (PP) from the pancreas and anorexigenic leptin from adiposites remain the most widely studied hormones. Homeostatic control of food intake occurs in humans, although its relative importance for eating behaviour is uncertain, compared with social and environmental influences. There are perturbations in the gut–brain axis in obese compared with lean individuals, as well as in weight-reduced obese individuals. Fasting and postprandial levels of gut hormones change when obese individuals lose weight, either with surgical or with dietary and/or exercise interventions. Diet-induced weight loss results in long-term changes in appetite gut hormones, postulated to favour increased appetite and weight regain while exercise programmes modify responses in a direction expected to enhance satiety and permit weight loss and/or maintenance. Sustained weight loss achieved by bariatric surgery may in part be mediated via favourable changes to gut hormones. Future work will be necessary to fully elucidate the role of each element of the axis, and whether modifying these signals can reduce the risk of obesity.
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146
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Kim M, Song SB, Cha YS. Effects of black adzuki bean (Vigna angularis, Geomguseul) extract on body composition and hypothalamic neuropeptide expression in rats fed a high-fat diet. Food Nutr Res 2015; 59:27719. [PMID: 26493717 PMCID: PMC4615815 DOI: 10.3402/fnr.v59.27719] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 10/05/2015] [Accepted: 10/05/2015] [Indexed: 01/18/2023] Open
Abstract
Background Obesity is often considered to result from either excessive food intake or insufficient physical activity. Adzuki beans have been evaluated as potential remedies for various health conditions, and recent studies have reported their effects on the regulation of lipid metabolism, but it remains to be determined whether they may be effective in overcoming obesity by regulating appetite and satiety. Objective This study investigated the effect of black adzuki bean (BAB) extract on body composition and hypothalamic neuropeptide expression in Sprague Dawley rats (Rattus norvegicus) fed a high-fat diet. Design The rats were fed for 8 weeks with a control diet containing 10 kcal% from fat (CD), a high-fat diet containing 60 kcal% from fat (HD), or a high-fat diet with 1% or 2% freeze-dried ethanolic extract powder of BAB (BAB-1 and BAB-2). Results The body weights and epididymal fat weights were significantly reduced and the serum lipid profiles were improved in the group fed the diet containing BAB compared to the HD group. The expression of AGRP mRNA significantly decreased in the BAB groups, and treatment with BAB-2 resulted in a marked induction of the mRNA expression of POMC and CART, which are anorexigenic neuropeptides that suppress food intake. Furthermore, mRNA expression levels of ObRb, a gene related to leptin sensitivity in the hypothalamus, were significantly higher in the BAB groups than in the HD group. Conclusions These results suggest that supplementation with BAB has a significant effect on body weight via regulation of hypothalamic neuropeptides.
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Affiliation(s)
- Mina Kim
- Department of Food Science and Human Nutrition, BK21 PLUS Program, Chonbuk National University, Jeonju, Republic of Korea
| | - Seok-Bo Song
- Department of Functional Crops, National Institute of Crop Science, Rural Development Administration, Miryang, Republic of Korea
| | - Youn-Soo Cha
- Department of Food Science and Human Nutrition, BK21 PLUS Program, Chonbuk National University, Jeonju, Republic of Korea;
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147
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148
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Role of Enhanced Central Leptin Activity in a Scoliosis Model Created in Bipedal Amputated Mice. Spine (Phila Pa 1976) 2015; 40:E1041-5. [PMID: 26192719 DOI: 10.1097/brs.0000000000001060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN An experimental study to investigate the role of enhanced central leptin activity in a bipedal mouse scoliosis model. OBJECTIVE To investigate the influence of enhanced central leptin activity on the development of scoliosis in mice, and to support Burwell's hypothesis that central leptin dysfunction is involved in the etiopathogenesis of idiopathic scoliosis. SUMMARY OF BACKGROUND DATA Significantly lower level of circulating leptin and higher level of soluble leptin receptor have been reported in adolescent idiopathic scoliosis compared with healthy adolescents, suggesting possible association between abnormal central leptin level and dysfunction. METHODS Amputation of forelimbs and tail was performed on 50 male C3H/HeJ mice at the age of 3 weeks. Then, the mice were randomly divided into 2 groups: Group A consisted of 25 mice treated with injection into the hypothalamus with lentivirus vectors that overexpressed leptin; and Group B involved the remaining 25 mice receiving intracerebral injection with the control vectors. Radiographs were obtained at 20th week to determine the presence of spinal deformity. The incidence of scoliosis and curve magnitude were compared between groups. RESULTS The body weight was initially found to be slightly lower in mice of Group A when compared with Group B. Significantly higher peripheral serum leptin level was found in leptin-overexpressing mice than control mice. Scoliosis developed in 23 mice of Group A (92%), with an average Cobb angle of 30.2°, and in 13 of Group B (52%), with an average Cobb angle of 18.4°, respectively. A higher incidence (P = 0.002) and more severe curve (P <0.001) were observed in Group A. CONCLUSION In this bipedal mouse scoliosis model, enhanced central leptin activity might not only increase the risk of developing a scoliosis, but also contribute to the progression of scoliosis. LEVEL OF EVIDENCE N/A.
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149
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Munusamy S, do Carmo JM, Hosler JP, Hall JE. Obesity-induced changes in kidney mitochondria and endoplasmic reticulum in the presence or absence of leptin. Am J Physiol Renal Physiol 2015; 309:F731-43. [PMID: 26290368 DOI: 10.1152/ajprenal.00188.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 08/13/2015] [Indexed: 12/17/2022] Open
Abstract
We investigated obesity-induced changes in kidney lipid accumulation, mitochondrial function, and endoplasmic reticulum (ER) stress in the absence of hypertension, and the potential role of leptin in modulating these changes. We compared two normotensive genetic mouse models of obesity, leptin-deficient ob/ob mice and hyperleptinemic melanocortin-4 receptor-deficient mice (LoxTB MC4R-/-), with their respective lean controls. Compared with controls, ob/ob and LoxTB MC4R-/- mice exhibit significant albuminuria, increased creatinine clearance, and high renal triglyceride content. Renal ATP levels were decreased in both obesity models, and mitochondria isolated from both models showed alterations that would lower mitochondrial ATP production. Mitochondria from hyperleptinemic LoxTB MC4R-/- mice kidneys respired NADH-generating substrates (including palmitate) at lower rates due to an apparent decrease in complex I activity, and these mitochondria showed oxidative damage. Kidney mitochondria of leptin-deficient ob/ob mice showed normal rates of respiration with no evidence of oxidative damage, but electron transfer was partially uncoupled from ATP synthesis. A fourfold induction of C/EBP homologous protein (CHOP) expression indicated induction of ER stress in kidneys of hyperleptinemic LoxTB MC4R-/- mice. In contrast, ER stress was not induced in kidneys of leptin-deficient ob/ob mice. Our findings show that obesity, in the absence of hypertension, is associated with renal dysfunction in mice but not with major renal injury. Alterations to mitochondria that lower cellular ATP levels may be involved in obesity-induced renal injury. The type and severity of mitochondrial and ER dysfunction differs depending upon the presence or absence of leptin.
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Affiliation(s)
- Shankar Munusamy
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi; Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, Mississippi; and College of Pharmacy, Qatar University, Doha, Qatar
| | - Jussara M do Carmo
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi; Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Jonathan P Hosler
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, Mississippi
| | - John E Hall
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi; Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, Mississippi; and
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Metabolic syndrome and obesity among users of second generation antipsychotics: A global challenge for modern psychopharmacology. Pharmacol Res 2015. [PMID: 26218604 DOI: 10.1016/j.phrs.2015.07.022] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Second generation antipsychotics (SGAs), such as clozapine, olanzapine, risperidone and quetiapine, are among the most effective therapies to stabilize symptoms schizophrenia (SZ) spectrum disorders. In fact, clozapine, olanzapine and risperidone have improved the quality of life of billions SZ patients worldwide. Based on the broad spectrum of efficacy and low risk of extrapyramidal symptoms displayed by SGAs, some regulatory agencies approved the use of SGAs in non-schizophrenic adults, children and adolescents suffering from a range of neuropsychiatric disorders. However, increasing number of reports have shown that SGAs are strongly associated with accelerated weight gain, insulin resistance, diabetes, dyslipidemia, and increased cardiovascular risk. These metabolic alterations can develop in as short as six months after the initiation of pharmacotherapy, which is now a controversial fact in public disclosure. Although the percentage of schizophrenic patients, the main target group of SGAs, is estimated in only 1% of the population, during the past ten years there was an exponential increase in the number of SGAs users, including millions of non-SZ patients. The scientific bases of SGAs metabolic side effects are not yet elucidated, but the evidence shows that the activation of transcriptional factor SRBP1c, the D1/D2 dopamine, GABA2 and 5HT neurotransmitions are implicated in the SGAs cardiovascular toxicity. Polypharmacological interventions are either non- or modestly effective in maintaining low cardiovascular risk in SGAs users. In this review we critically discuss the clinical and molecular evidence on metabolic alterations induced by SGAs, the evidence on the efficacy of classical antidiabetic drugs and the emerging concept of antidiabetic polyphenols as potential coadjutants in SGA-induced metabolic disorders.
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