urolithin-b and Muscular-Atrophy

To highlight recent evidence for the ability of polyphenols and their derivatives to reduce muscle wasting in different pathological states.. From January 2016 to August 2017, four articles dealt with the effects of polyphenols on muscle wasting, which were all carried out in mice. The four studies found that polyphenols reduced muscle mass loss associated with cancer cachexia, acute inflammation or sciatic nerve section. One study even showed that muscle mass was totally preserved when rutin was added to the diet of mice undergoing cancer cachexia. The beneficial effects of polyphenols on muscle wasting were mainly due to a reduction in the activation of the nuclear factor-kappa B pathway, a lower oxidative stress level and a better mitochondrial function. In addition, urolithin B was found to have a testosterone-like effect and to favorably regulate muscle protein balance.. During the last 20 months, additional data have been collected about the beneficial effects of rutin, curcumin, quercetin, ellagitanins and urolithin B to limit the loss of muscle mass associated with several pathological states. However, currently, scientific evidence lacks for their use as nutraceuticals in human.

Topics: Animals; Cachexia; Coumarins; Curcumin; Humans; Hydrolyzable Tannins; Mitochondria; Muscle, Skeletal; Muscular Atrophy; NF-kappa B; Oxidative Stress; Phytotherapy; Plant Extracts; Polyphenols; Quercetin; Rutin; Wasting Syndrome

The control of muscle size is an essential feature of health. Indeed, skeletal muscle atrophy leads to reduced strength, poor quality of life, and metabolic disturbances. Consequently, strategies aiming to attenuate muscle wasting and to promote muscle growth during various (pathological) physiological states like sarcopenia, immobilization, malnutrition, or cachexia are needed to address this extensive health issue. In this study, we tested the effects of urolithin B, an ellagitannin-derived metabolite, on skeletal muscle growth.. C2C12 myotubes were treated with 15 μM of urolithin B for 24 h. For in vivo experiments, mice were implanted with mini-osmotic pumps delivering continuously 10 μg/day of urolithin B during 28 days. Muscle atrophy was studied in mice with a sciatic nerve denervation receiving urolithin B by the same way.. Our experiments reveal that urolithin B enhances the growth and differentiation of C2C12 myotubes by increasing protein synthesis and repressing the ubiquitin-proteasome pathway. Genetic and pharmacological arguments support an implication of the androgen receptor. Signalling analyses suggest a crosstalk between the androgen receptor and the mTORC1 pathway, possibly via AMPK. In vivo experiments confirm that urolithin B induces muscle hypertrophy in mice and reduces muscle atrophy after the sciatic nerve section.. This study highlights the potential usefulness of urolithin B for the treatment of muscle mass loss associated with various (pathological) physiological states.

Topics: Animals; Cell Differentiation; Cells, Cultured; Coumarins; Female; Male; Mice; Mice, Inbred C57BL; Muscle Fibers, Skeletal; Muscle Proteins; Muscle, Skeletal; Muscular Atrophy; Proteasome Endopeptidase Complex; Receptors, Androgen; Signal Transduction; Ubiquitin-Protein Ligases