Screening of 100 plant extracts for the development of a herbal product effective against muscle atrophy

Skeletal muscle atrophy is a loss of muscle mass/strength associated with aging (sarcopenia) or several pathologies including inflammatory diseases, nutrient deprivation, and prolonged treatment with glucocorticoids (GCs) [1]. Despite it represents an enormous medical problem that accelerates the disease progression, increases the hospitalization, and worsens quality of patients’ life, an effective therapy is still lacking. Regardless of etiology, the activation of myofibrillary protein breakdown, especially myosin heavy chain (MyHC), and the reduction of protein synthesis are recognized as the main processes promoting muscle atrophy [1]. The potential of plant metabolites as protective agents against muscle atrophy has been reported [2]. Thus, this work was aimed to individuate promising plants to contrast muscular atrophy, and suitable to develop a herbal product to be marketed. One hundred hydroalcoholic extracts from medical plants were tested in well-characterized in vitro experimental models mimicking muscle atrophy, i.e, treatment of myotubes from C2C12 myoblasts with proinflammatory cytokines (TNFα/IFNγ), nutrient deprivation (starvation) or excess GCs (dexamethasone) [1]. Ten extracts showed extremely potent protective effects against MyHC degradation, as indicated by measurements of myotube diameters, even if at various extent in different atrophic conditions. In particular, four out of them were capable to completely counteract the catabolic effect of TNFα/IFNγ and dexamethasone, and five showed a strong activity against nutrient deprivation. Panax ginseng Meyer emerged as the most potent anti-atrophic agent, together with Withania somnifera Dunal and Silybum marianum Gaertner. Twenty combinations of six extracts selected for their NMR-based metabolic profiles are under investigation, with particular regard to the molecular mechanisms used to counteract muscle atrophy. Our results might lead to the formulation of a low-cost, non-toxic phytotherapy product able to prevent/counteract muscular atrophy associated with aging and pathological conditions. 1 Bonaldo and Sandri 2013 Dis Model Mech 2 Jeong et al. 2018 Evid Based Complement Alternat Med