Vol. 76 (2) 2024

ARTICLES

Effects of Submaximal Training on Ghrelin in Female
and Male Rats with Dietary-Induced Metabolic Syndrome

Petar Hrischev1, Pepa Atanassova2, Katerina Georgieva1, Vesela Yancheva3, Stela Stoyanova4*, Iliana Velcheva3 & Elenka Georgieva4

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1Department of Physiology, Medical Faculty, Medical University – Plovdiv, 4000 Plovdiv, Bulgaria; E-mail: petar.hrischev@mu-plovdiv.bg; katerina.georgieva@mu-plovdiv.bg
2Department of Anatomy, Histology and Embryology, Medical Faculty, Medical University – Plovdiv, 4000 Plovdiv, Bulgaria; E-mail: pepa.atanasova@mu-plovdiv.bg
3Department of Ecology and Environmental Conservation, Faculty of Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria; E-mail: vyancheva@uni-plovdiv.bg; anivel@uni-plovdiv.bg
*4Department of Developmental Biology, Faculty of Biology. University of Plovdiv, 4000 Plovdiv, Bulgaria; E-mail: stela.stoyanova@uni-plovdiv.bg; elenkageorgieva@uni-plovdiv.bg

https://doi.org/10.71424/azb76.2.002724

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Abstract
Ghrelin is a hormone that stimulates appetite and its serum levels are inversely proportional to body weight. Decreased ghrelin levels correlate with obesity, insulin resistance and elevated blood pressure, which are components of the metabolic syndrome (MetS). The effect of physical exercise is studied mainly after an already induced MetS, the results are contradictory and it is not clear what the effect of exercise on ghrelin concentration is. There are no data for gender comparisons of changes in ghrelin due to submaximal training. In this study, we aimed to determine the effect of submaximal training on serum ghrelin concentrations during the dietary induction of MetS in female and male rats. Dietary-manipulated female and male Wistar rats (n = 32) were used. They were divided into four groups: male and female sedentary (MD and FD) and male and female trained on treadmill (MDT and FDT). For 16 weeks, the four groups received high-fat high-carbohydrate (HFHC) food and both MDT and FDT simultaneously with the diet were subjected to submaximal training (70-75% VO2max). At the end of the experiment, mixed blood was collected and ghrelin concentrations were measured. The submaximal training and gender had a significant main effect on ghrelin levels, as trained dietary-manipulated rats had higher serum concentrations compared to the sedentary (p < 0.05) and males had higher concentrations compared to females (p < 0.05). Overall, applied for 16 weeks, simultaneously with the combined HFHC diet, the submaximal training had a positive effect, lowering the serum ghrelin concentration. Sexual dimorphism, characterised by higher ghrelin in male rats, was also found.

Key words
Ghrelin, metabolic syndrome, submaximal training, female and male Wistar rats

How to Cite
Hrischev P., Atanassova P., Georgieva K., Yancheva V., Stoyanova S., Velcheva I. & Georgieva E. 2024. Effects of Submaximal Training on Ghrelin in Female and Male Rats with Dietary-Induced Metabolic Syndrome. Acta zoologica bulgarica 76 (2) 197-205.

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