Toppfinansiering av prosjekt
We proposed to examine the effects of a 12-week supervised exercise programme, in sedentary overweight/obese individuals, on the fasting/postprandial plasma levels of appetite-regulating hormones and inflammatory biomarkers. Moreover, we aimed to investigate if changes in these markers were modulated by weight/fat mass loss.We have performed radioimmunoassays for the measurement of obestatin, leptin and glucose insulinotropic peptide (GIP) in order to assess the impact of a 12-week exercise program on the plasma levels of these hormones involved in appetite control and metabolism. We finished most of the lab work and performed data analyses for the available data. We found the following results: - Exercise-induced weight loss had no significant impact on the fasting or postprandial plasma levels of obestatin, a novel peptide encoded by the same gene as ghrelin and potentially with opposite actions (anorexigenic) in the regulation of food intake and body weight. - Exercise-induced weight loss increased significantly the ratio total ghrelin/obestatin, paralleling the increase observed in subjective feelings of hunger. - Exercise also resulted in a significant reduction in leptin plasma levels both in fasting and postprandially. - As expected, females presented with higher leptin plasma levels, but the response to exercise was not modulated by gender. - The reduction in fasting and postprandial leptin levels was not correlated with the extend of fat mass loss indicating that other factors are involved in determining leptin secretion apart from fat mass in itself. - Exercise-induced weight loss reduced fasting GIP, but had no impact on the postprandial release of this hormone after a mixed meal. - There was no correlation between the changes in either fasting or postprandial obestatin or GIP and changes in weight/fat mass with the exercise program. - Opposite to our expectations GIP does not seem to be involved in modulating fat oxidation, and as a consequence fat mass loss, following an exercise intervention. We plan to finish lab work and data analysis soon and to submit a paper with the results in the next couple of months.