Proanthocyanidins Induce miR-133b Expression to Promote Ischemic Skeletal Muscle Regeneration by Targeting MKP1
Background: Limb ischemic necrosis is mainly attributed to peripheral arterial disease (PAD). Reducing oxidative stress and promoting damaged skeletal muscle regeneration may be benefit for ischemic limb treatment. Proanthocyanidins (PC) is a powerful antioxidant and free radical scavenger, but little is known about its role and related molecular mechanism in limb ischemic injury. The current study was undertaken to explore its role in the damaged skeletal muscle regeneration both in vitro and
... both in vitro and vivo, and whether MicroRNAs (miRNAs) involved in this process. Methods: The potential effects of PC on the damaged muscle regeneration were explored in human skeletal muscle satellite cells (HSKMSCs) under hypoxic-ischemic condition and in mice limb ischemia model, then, aberrant expression of miRNAs in ischemic skeletal muscles were determined by microarray analysis, and regulatory mechanism of the specific miRNA on HSKMSCs myogenic differentiation was further investigated by gain and loss of functional experiments. Additionally, the direct target gene was examined by luciferase reporter assay.Results: In mice limb ischemia model, our results revealed that PC reduced oxidative stress level, significantly promoted ischemic limb damaged muscle regeneration and motor function recovery, then, aberrant expression of miRNAs in ischemic skeletal muscles were determined by microarray analysis, combine with the results of the RT-qPCR, the miR-133b-3p was proved to be the specific miRNA. In vitro, our results revealed that PC induced the overexpression of miR-133b to activate the p38-MAPK signal pathway and increased the myogenic differentiation-related molecules expression, which eventually promoted myotubes formation. Furthermore, MKP1 was confirmed a direct target gene of miR-133b.Conclusion: Our results suggest that PC display skeletal muscle protective properties that are mediated by miR-133b /MKP1/ p38-MAPK signal axis, offering a novel therapeutic opportunity for limb ischemic injury.