Effect of RONS-Induced Intracellular Redox Homeostasis in 6-NBDG/Glucose Uptake in C2C12 Myotubes and Single Isolated Skeletal Muscle Fibres

Unresolved questions in the regulation of skeletal muscle insulin action by reactive oxygen species

Reactive oxygen species (ROS) are well-established signaling molecules implicated in a wide range of cellular processes, including both oxidative stress and intracellular redox signaling. In the context of insulin action within its target tissues, ROS have been reported to exert both positive and negative regulatory effects. However, the precise molecular mechanisms underlying this duality remain unclear. This Review examines the complex role of ROS in insulin action, with a particular focus on skeletal muscle. We aim to address three critical aspects: (a) the proposed intracellular pro-oxidative redox shift elicited by insulin, (b) the evidence supporting that redox-sensitive cysteine modifications impact insulin signaling and action, and (c) cellular mechanisms underlying how ROS can paradoxically act as both enhancers and inhibitors of insulin action. This Review underscores the urgent need for more systematic research to identify specific reactive species, redox targets, and the physiological significance of redox signaling in maintaining insulin action and metabolic health, with a particular emphasis on human skeletal muscle.

Bioguided isolation, identification and bioactivity evaluation of anti-fatigue constituents from Schizophyllum commune

This study aims to clarify the specific anti-fatigue components of Schizophyllum commune (S.commune) and analyze its potential anti-fatigue mechanism. The main anti-fatigue active ingredient of S.commune was locked in n-butanol extract (SPE-n) by activity evaluation. Twelve compounds were identified by high performance liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS). The anti-fatigue effect of morusin is the most predominant among these 12 ingredients. The determination of biochemical indices showed that morusin could increase liver glycogen reserves, improve the activity of antioxidant enzymes in liver, and reduce reactive oxygen species (ROS) content in muscle tissue, thereby reducing myocyte damage. Further studies revealed that morusin could reduce the level of oxidative stress by activating Nrf2/HO-1 pathway, thus alleviating the fatigue of mice caused by exhaustive exercise. The current findings provide a theoretical basis for the development of natural anti-fatigue functional food.