Supplementation with Lactobacillus rhamnosus SP1 normalises skin expression of genes implicated in insulin signalling and improves adult acne

Systemic supplementation with probiotics is increasingly being explored as a potential treatment strategy for skin disorders. Because both the gut-skin axis and dysregulation of insulin signalling have been implicated in the pathogenesis of adult acne, we designed the current study to evaluate the effect of supplementation with the probiotic strain Lactobacillus rhamnosus SP1 (LSP1) on skin expression of genes involved in insulin signalling and acne improvement in adult subjects. A pilot, randomised, double-blinded, placebo-controlled study was conducted with 20 adult subjects (14 females and 6 males; mean age: 33.7±3.3 years) with acne. Over a 12-week period, the probiotic group (n=10) consumed a liquid supplement containing LSP1 at a dose of 3×109 cfu/day (75 mg/day), whereas the placebo group (n=10) received a liquid lacking probiotics. Paired skin biopsies - one obtained before treatment initiation and one obtained at the end of the 12-week treatment period - were analysed for insulin-like growth factor 1 (IGF1) and forkhead box protein O1 (FOXO1) gene expression. The clinical criterion for efficacy was the investigator's global improvement rating on a five-point scale. Compared with baseline, the probiotic group showed a 32% (P<0.001) reduction, as well as a 65% increase (P<0.001) in IGF1 and FOXO1 gene expression in the skin, respectively. No such differences were observed in the placebo group. Patients in the probiotic group had an adjusted odds ratio of 28.4 (95% confidence interval = 2.2-411.1, P<0.05) to be rated by physicians as improved/markedly improved (versus worsened or unchanged) compared with the placebo group. We conclude that supplementation with the probiotic strain LSP1 normalises skin expression of genes involved in insulin signalling and improves the appearance of adult acne.

Effects of allopurinol on exercise-induced muscle damage: new therapeutic approaches?

Intensive muscular activity can trigger oxidative stress, and free radicals may hence be generated by working skeletal muscle. The role of the enzyme xanthine oxidase as a generating source of free radicals is well documented and therefore is involved in the skeletal muscle damage as well as in the potential transient cardiovascular damage induced by high-intensity physical exercise. Allopurinol is a purine hypoxanthine-based structural analog and a well-known inhibitor of xanthine oxidase. The administration of the xanthine oxidase inhibitor allopurinol may hence be regarded as promising, safe, and an economic strategy to decrease transient skeletal muscle damage (as well as heart damage, when occurring) in top-level athletes when administered before a competition or a particularly high-intensity training session. Although continuous administration of allopurinol in high-level athletes is not recommended due to its possible role in hampering training-induced adaptations, the drug might be useful in non-athletes. Exertional rhabdomyolysis is the most common form of rhabdomyolysis and affects individuals participating in a type of intense exercise to which they are not accustomed. This condition can cause exercise-related myoglobinuria, thus increasing the risk of acute renal failure and is also associated with sickle cell trait. In this manuscript, we have reviewed the recent evidence about the effects of allopurinol on exercise-induced muscle damage. More research is needed to determine whether allopurinol may be useful for preventing not only exertional rhabdomyolysis and acute renal damage but also skeletal muscle wasting in critical illness as well as in immobilized, bedridden, sarcopenic or cachectic patients.

Inconsistency in circulating irisin levels: what is really happening?

The discovery of irisin as a novel and promising peptidic hormone for the treatment of obesity and diabetes has recently been reported. As a result, great hopes have been raised based on this finding, hypothesizing that irisin might provide additional benefits, not only for obesity and diabetes, but also for a wide range of pathological conditions requiring therapeutical and clinical attention. However, controversial results and conclusions on circulating irisin concentrations and correlations with other variables, including its role in metabolism, have recently been reported. Although laboratory assessment of irisin by ELISA is easily available and may provide interesting information for therapeutics and clinical practice, the heterogeneous and often discrepant results published so far, raise serious concerns about its measurement, indicating that it may still not be ready for use or whether irisin really exists. We highlight here some aspects on these discrepancies and contradictions, and put forward their implications.

Allopurinol prevents cardiac and skeletal muscle damage in professional soccer players

Xanthine oxidase (XO), a free radical-generating enzyme, is involved in tissue damage produced during exhaustive exercise. Our aim was to test whether allopurinol, a powerful inhibitor of XO, may be effective in preventing exercise-induced tissue damage in soccer players. Twelve soccer players were randomized into two experimental groups. One received allopurinol, before a match of the premier Spanish Football League, and the other placebo. Allopurinol prevented the exercise-induced increase in all the markers of skeletal muscle damage analyzed: creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and myoglobin. Creatine kinase-MB isoenzyme and highly sensitive troponin T, specific biomarkers of myocardial injury, increased significantly in the placebo but not in the allopurinol-treated group after the football match. We also found that the exercise-induced lipid peroxidation, as reflected by malondialdehyde measurements, was prevented after allopurinol administration. However, inhibition of XO did not prevent the increment in the activity of alanine aminotransferase found after the match. No changes in the serum gamma glutamyltransferase activity was found after the match on either the placebo and the allopurinol groups. These two enzymes were determined as biomarkers of liver injury. Allopurinol represents an effective and inexpensive pharmacological agent to prevent tissue damage in soccer players.

Impact of exercise training on neuroplasticity-related growth factors in adolescents

OBJECTIVES

We aimed to determine the effect of exercise training on plasma levels of brain-derived neurotrophic factor (BDNF), and serum insulin-like growth factor-1 (IGF-1) as well as cAMP response element-binding (CREB) activation in peripheral blood mononuclear cells (PBMCs) in adolescents.

METHODS

Nine trained and seven sedentary male adolescents, matched in age (14.0±2.2 years), were recruited for the study. Trained boys performed higher physical activity levels (expressed both as total energy expenditure and as physical activity energy expenditure) and showed significant bradycardia when compared with sedentary ones.

RESULTS

We found that BDNF and IGF-1 levels were significantly higher in trained adolescents than in sedentary ones. However, no effect of training was found in the activation of CREB in PBMCs.

CONCLUSIONS

We demonstrated the increase of neuroplasticity-related proteins due to exercise training in adolescents. Our results emphasize the significance and impact of exercise in this developmental period.