Mitochondrial Biogenesis, Reduction of Muscle Oxidative Damage and Improvement in Adipose Tissue Functional Profile, Account for the Beneficial Effects of Exercise and Healthy Diets

Both dietary caloric restriction (CR) and physical exercise (PE) exert beneficial effects, which retard or prevent age-related diseases and prolong life span. Subjects with the metabolic syndrome age prematurely, therefore preventive measures should be initiated early. The present study intends to demonstrate that physical exercise and/or Mediterranean diet, in middle aged volunteers with the metabolic syndrome, preserve adequate adipose tissue functionality and retard skeletal muscle aging (assessed by mitochondrial biogenesis and accumulation of ROS), by activating several pathways, homologous to CR. The investigators plan to study this by using two approaches: 1) A cross- sectional model, in which the expression of the mentioned metabolic mediators, indicators of muscle mitochondrial biogenesis and muscle oxidative damage will be compared between men with different body compositions, fat distribution, muscle strength and exercise capacity (VO2max). Also, in these men the investigators will assess the expression of uncoupling protein 1 (UCP1) in subcutaneous white adipose tissue (as a measure of adaptive thermogenesis), and inflammatory markers (Interleukin 1-6, Interleukin 1ß and CCL2 chemokine (C-C motif ligand 2)) in preperitoneal adipose tissue, plus inflammation and adipogenesis potential of their cultured preadipocytes. Moreover, in vitro studies will evaluate the functional effects of exposure of a cell lyne of human adipocyte cells (LS14)to factors secreted by media conditioned by the patients´ adipose tissue explants. 2) A prospective intervention in overweight/moderately obese middle aged volunteers that will be assigned to a weight-maintenance period (as a control group), and then randomly y assigned to a Mediterranean diet, exercise training or diet plus training. Before and after 3 months of intervention the investigators will obtain muscle tissue samples to study the expression of Peroxisome proliferator activated receptor (PPAR) gamma coactivator 1 alpha (PGC1), uncoupling protein 3 (UCP3), AMP activated protein kinase (AMPK), Sirtuin 1 (SIRT-1), mitochondrial DNA and oxidative damage indicators (8-oxo-7,8-dihydro-2-deoxyguanosine (oxodG), carboxymethyllysine (CML and its receptor (RAGE)). In vitro studies will evaluate the effect of circulating factors from the patients (serum) on LS14 inflammatory and adipogenic potential, at baseline and after 3 months of intervention.