SPRED1 in quadriceps of patients with mild chronic obstructive pulmonary disease (1102.21)

Limb muscle dysfunction contributes to exercise intolerance in chronic obstructive pulmonary disease (COPD). In turn, quadriceps capillarization is a determinant of muscle function. In our previous study, the number of capillaries and mRNA level of VEGFA were both reduced in mild COPD. MicroRNAs (miRs) regulate biological processes such as angiogenesis. Based on the literature, angiogenesis can be regulated by miR‐126 which blocked the expression of an inhibitor of angiogenesis, SPRED1. In this study, we assessed the expression of miR‐126 in the context of capillarization characterization in muscle tissue obtained from a needle biopsy in 5 patients with mild COPD and 5 healthy age‐matched controls. We hypothesized that miR‐126 will be downregulated and SPRED1 will be enhanced in COPD. Vastus lateralis muscle samples were analyzed for miRs and mRNA content by qPCR and the number of capillaries was obtained by immunochemistry. Levels of miR‐126 were similar between mild COPD and healthy controls. SPRED1 level was enhanced by 2.1 fold (p=0.01) and the number of capillaries tended to be reduced in mild COPD compared to healthy controls. SPRED1 may have a role in limb muscle capillarization in mild COPD. Investigations targeting specifically endothelial cells will better dissect the biochemical process involved in muscle angiogenesis in the context of COPD. Grant Funding Source : CHIR/IRSC