Leptin is a recently discovered hormone which is involved in the regulation of body weight. It provides a molecular basis for the lipostatic theory of the regulation of energy balance. White adipose tissue is the main site of leptin synthesis and there is some evidence of ob gene expression in brown fat. Leptin seems to play a key role in the control of body fat stores by coordinated regulation of feeding behaviour, metabolic rate, autonomic nervous system regulation and body energy balance in rodents, primates and humans. Apart from the function of leptin in the central nervous system on the regulation of energy balance, it may well be one of the hormonal factors that signal the body's readiness for sexual maturation and reproduction to the brain. During late pregnancy and at birth when maternal fat stores have been developed leptin levels are high. Leptin could then be a messenger molecule signaling the adequacy of the fat stores for reproduction and maintenance of pregnancy. At later stages of gestation leptin could signal the expansion of fat stores in order to prepare the expectant mother for the energy requirements of full term gestation, labour and lactation. This overview focuses on those topics of leptin research which are of particular interest in reproductive medicine and gynecology.
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http://dx.doi.org/10.1016/s0301-2115(99)00150-5 | DOI Listing |
Pediatr Obes
December 2024
Laboratory of the Metabolic Adaptations to Exercise under Physiological and Pathological Conditions (AME2P), Clermont Auvergne University, Clermont-Ferrand, France.
Introduction: This work aims at evaluating the adaptations of the energy cost of walking (Cw) to simulated weight gain at different walking speeds in adolescents with obesity.
Methods: Substrate use and Cw were evaluated during a graded walking exercise (4 × 5min at 0.75, 1, 1.
Curr Dev Nutr
January 2025
School of Food Science and Nutrition, University of Leeds, Leeds, West Yorkshire, United Kingdom.
Background: Regulations restricting the promotion of some less-healthy products high in fat, sugar, or salt (HFSS) within "restricted areas" (RAs) of supermarkets came into force in October 2022 in England.
Objectives: To evaluate the prevalence of HFSS products and front-of-pack nutrition labeling (FOPNL) characteristics of foods sold within RAs in a sample of supermarket stores.
Methods: A cross-sectional survey of products in RAs in 3 supermarkets was undertaken from November 2022 to February 2023 using photographs, recording the display of FOPNL.
Sci Rep
December 2024
School of Mechanical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China.
Microtextured microneedles are tiny needle-like structures with micron-scale microtextures, and the drugs stored in the microtextures can be released after entering the skin to achieve the effect of precise drug delivery. In this study, the skin substitution model of Ogden's hyperelastic model and the microneedle array and microtexture models with different geometrical parameters were selected to simulate and analyse the flow of the microtexture microneedle arrays penetrating the skin by the finite-element method, and the length of the microneedles was determined to be 200 μm, the width 160 μm, and the value of the gaps was determined to be 420 μm. A four-pronged cone was chosen as the shape of microneedles, and a rectangle was chosen as the shape of the drug-carrying microneedle.
View Article and Find Full Text PDFCryobiology
January 2025
Institute of Biochemistry and Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada.
The garden dormouse (Eliomys quercinus) is a fat-storing mammal that undergoes annual periods of hibernation to mitigate the effects of food scarcity, low ambient temperatures, and reduced photoperiod that characterize winter. Like other hibernating species, this animal suppresses its metabolic rate by downregulating nonessential genes and processes in order to prolong available energy stores and limit waste accumulation throughout the season. MicroRNAs (miRNAs) are short, single-stranded, noncoding RNAs that bind to mRNA and mediate post-transcriptional suppression, making miRNA ideal for modulating widespread changes in gene expression, including global downregulation typified by metabolic rate depression.
View Article and Find Full Text PDFFood Sci Nutr
December 2024
Food and Nutrition Policy and Planning Research Department, Faculty of Nutrition Sciences and Food Technology National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences Tehran Iran.
This study aims to comparatively analyze butter, ghee, and margarine fatty acid profiles and their implications for healthier fat and oil group choices. In this cross-sectional study, 60 samples from best-selling brands of butter, ghee, and margarine were randomly selected from five food chain stores in Tehran, Iran. Then, all the samples were coded, packed in cool conditions, and sent to the laboratory to determine the fatty acid profiles by using gas chromatography (GC).
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