Objectives: It has been demonstrated that leptin influences the energy balance by regulating appetite and increasing energy expenditure (EE). However, the relationship between circulating leptin and EE is confounded owing to variations in body composition. The aim of this study was to determine the role of circulating leptin in energy regulation and to examine whether the leptin-mediated changes in EE are associated with adiposity among healthy adults living in Singapore.
Methods: We conducted a cross-sectional study of 300 participants (112 men). Resting metabolic rate (RMR) was measured by indirect calorimetry. Body composition (i.e., fat mass [FM] and fat-free mass [FFM]) was measured by dual-energy x-ray absorptiometry. Serum leptin levels were determined by radioimmunoassay.
Results: There were strong correlations between circulating leptin levels, FM, and RMR in healthy men and women. After normalization of RMR by a power function model (kcal·kg FFM·d), the influence of FFM can be effectively removed. The normalized RMR was significantly associated with both FM (r = 0.28, P < 0.001) and log leptin (r = 0.35, P < 0.001). In the stepwise multiple regression analysis, leptin level is the major predictor for normalized RMR, accounting for 12% of the variation. In contrast, FM did not explain any variation in normalized RMR.
Conclusion: Leptin may be a more significant predictor of normalized RMR than FM per se. The contribution of FM to RMR could be via a mechanism that is related to leptin-dependent responses involved in energy homeostasis.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.nut.2018.08.015 | DOI Listing |
J Clin Med
January 2025
Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Goudi, Greece.
Glucose metabolism and hormonal responses are largely affected by exercise intensity, which exhibits an alternating pattern in many sports activities. The aim of this study was to investigate and compare glycemic and hormonal responses during and after exercise of constant (CON) and alternating (ALT) intensity with the same duration and total work. Ten healthy male volunteers performed two, 60 min cycling exercise bouts in random order: the ALT bout, where exercise intensity alternated between 46.
View Article and Find Full Text PDFBiomolecules
December 2024
Centre for Experimental Medicine, Institute for Clinical and Experimental Medicine, 140 21 Prague, Czech Republic.
We investigated the sex-dependent effects of inflammatory responses in visceral adipose tissue (VAT) and perivascular adipose tissue (PVAT), as well as hematological status, in relation to cardiovascular disorders associated with prediabetes. Using male and female hereditary hypertriglyceridemic (HHTg) rats-a nonobese prediabetic model featuring dyslipidemia, hepatic steatosis, and insulin resistance-we found that HHTg females exhibited more pronounced hypertriglyceridemia than males, while HHTg males had higher non-fasting glucose levels. Additionally, HHTg females had higher platelet counts, larger platelet volumes, and lower antithrombin inhibitory activity.
View Article and Find Full Text PDFDiabetes Obes Metab
January 2025
Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
Background: Medications targeting the leptin and Apolipoprotein CIII (APOC3) pathways are currently under development for the treatment of hypertriglyceridaemia. Given that both pathways are implicated in triglyceride regulation, it is unknown whether they function independently or interact under physiological conditions and under acute or long-term energy deficiency.
Methods: APOC3 levels and their association with circulating lipids and lipoproteins were evaluated in the context of two randomised controlled studies.
Am J Hypertens
January 2025
Department of Cardiology and Medicine, Hvidovre Hospital, Hvidovre, Denmark.
Background: Leptin is a hormone which is secreted by the adipocytes. In the circulation, leptin levels are directly proportional to the body fat percentage. Studies have shown that higher leptin levels are associated with an increased risk of hypertension after adjusting for body mass index (BMI).
View Article and Find Full Text PDFClin Immunol
January 2025
Division of Immunology, Boston Children's Hospital, Boston, MA, United States of America. Electronic address:
Epidemiologic studies have shown a continuous increase in mortality risk associated with overweight, thus highlighting the health risks beginning before the onset of obesity. However, early changes in inflammatory signaling induced by an obesogenic diet remain largely unknown since studies of obesity typically utilize models induced by months of continuous exposure to a high-fat diet. Here, we investigated how short-term overfeeding remodels inflammatory signaling.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!