Physical activity modify skeletal muscle fiber types in an animal model of metabolic syndrome

Metabolic Syndrome (MetS) is a cluster of clinical conditions, associated to an increased cardiovascular risk, as well as to hypogonadism in males. Lifestyle modification (including physical exercise, PhyEx) may be beneficial for the condition. Skeletal muscles (SkM) are some of the most highly plastic tissues, able of remodeling in response to use, disuse and disease. In particular, transformations of fiber type may occur in response to physiological milieu to induce functional adaptations. This study is aimed at investigating in experimental MetS, high fat diet-induced in male rabbits [1], the effect of PhyEx on hormonal and metabolic parameters, as well as on SkM composition. Control and MetS rabbits were exercise-trained to run on a treadmill for 12 weeks. Quadriceps femoris samples were collected for histomorphological and gene expression analyses. We found that exercise resistance was significantly reduced in MetS rabbits, as demonstrated by the significant reduction of both running time and distance, compared to control group. MetS rabbits also exhibited the lowest quadriceps mass. Fiber typing by PAS-staining showed a pronounced shift from slower type I to faster type II fibers in MetS group in response to PhysEx, suggesting that MetS condition addressed SkM function towards anaerobic metabolism. Accordingly, extracellular lactate levels were significantly increased and mitochondrial respiration-related genes reduced in SkM of MetS rabbits respect to controls. Interestingly, PhyEx significantly counteracted MetS-related testosterone deficiency and hypercholesterolemia. In conclusion, our results indicate that dysmetabolic milieu induces a reduced proportion of fatigue-resistant type I fibers in response to PhysEx, which however resulted beneficial for MetS condition

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

Contribution of Rare and Low-Frequency Variants to Multiple Sclerosis Susceptibility in the Italian Continental Population

Genome-wide association studies identified over 200 risk loci for multiple sclerosis (MS) focusing on common variants, which account for about 50% of disease heritability. The goal of this study was to investigate whether low-frequency and rare functional variants, located in MS-established associated loci, may contribute to disease risk in a relatively homogeneous population, testing their cumulative effect (burden) with gene-wise tests. We sequenced 98 genes in 588 Italian patients with MS and 408 matched healthy controls (HCs). Variants were selected using different filtering criteria based on allelic frequency and in silico functional impacts. Genes showing a significant burden (n = 17) were sequenced in an independent cohort of 504 MS and 504 HC. The highest signal in both cohorts was observed for the disruptive variants (stop-gain, stop-loss, or splicing variants) located in EFCAB13, a gene coding for a protein of an unknown function (p < 10(-4)). Among these variants, the minor allele of a stop-gain variant showed a significantly higher frequency in MS versus HC in both sequenced cohorts (p = 0.0093 and p = 0.025), confirmed by a meta-analysis on a third independent cohort of 1298 MS and 1430 HC (p = 0.001) assayed with an SNP array. Real-time PCR on 14 heterozygous individuals for this variant did not evidence the presence of the stop-gain allele, suggesting a transcript degradation by non-sense mediated decay, supported by the evidence that the carriers of the stop-gain variant had a lower expression of this gene (p = 0.0184). In conclusion, we identified a novel low-frequency functional variant associated with MS susceptibility, suggesting the possible role of rare/low-frequency variants in MS as reported for other complex diseases

Antiinflammatory effect of androgen receptor activation in human benign prostatic hyperplasia cells

Progression of benign prostatic hyperplasia (BPH) involves chronic inflammation and immune dysregulation. Preclinical studies have demonstrated that prostate inflammation and tissue remodeling are exacerbated by hypogonadism and prevented by testosterone supplementation. We now investigated whether, in humans, hypogonadism was associated with more severe BPH inflammation and thein vitroeffect of the selective androgen receptor agonist dihydrotestosterone (DHT) on cultures of stromal cells derived from BPH patients (hBPH). Histological analysis of inflammatory infiltrates in prostatectomy specimens from a cohort of BPH patients and correlation with serum testosterone level was performed. Even after adjusting for confounding factors, hypogonadism was associated with a fivefold increased risk of intraprostatic inflammation, which was also more severe than that observed in eugonadal BPH patients. Triggering hBPH cells by inflammatory stimuli (tumor necrosis factor α, lipopolysaccharide, or CD4+T cells) induced abundant secretion of inflammatory/growth factors (interleukin 6 (IL6), IL8, and basic fibroblast growth factor (bFGF)). Co-culture of CD4+T cells with hBPH cells induced secretion of Th1 inducer (IL12), Th1-recruiting chemokine (interferon γ inducible protein 10, IP10), and Th2 (IL9)- and Th17 (IL17)-specific cytokines. Pretreatment with DHT inhibited NF-κB activation and suppressed secretion of several inflammatory/growth factors, with the most pronounced effects on IL8, IL6, and bFGF. Reduced inflammatory cytokine production by testosterone cells, an increase in IL10, and a significant reduction of testosterone cells proliferation suggested that DHT exerted a broad antiinflammatory effect on testosterone cells. In conclusion, our data demonstrate that DHT exerts an immune regulatory role on human prostatic stromal cells, inhibiting their potential to actively induce and/or sustain autoimmune and inflammatory responses