miR-128 Is Implicated in Stress Responses by Targeting MAFG in Skeletal Muscle Cells

Figure 5

miR-128 downmodulation regulates MAFG increase in hypoxic condition both in vitro and in vivo. C2C12 cells were exposed to hypoxia (2% O2) for 4 h, and miR-128 levels (a) were determined by RT-qPCR on total RNAs after normalization with the small RNU6. Data are expressed as relative to the values obtained in untreated control which were set equal to 1. Each column in the panels represents the mean ± SD of 3 independent experiments. . Western blotting analysis (b) of HIF-1α, MAFG, and HMOX-1 was performed on total extracts from the same cells, as described in Materials and Methods. Tubulin was used as a loading control. mRNA levels of HMOX-1 and x-CT genes (c) were determined by RT-qPCR on total RNAs, and relative changes were calculated by comparing treated cells versus control, after normalization with c-ABL. Data were reported as relative to the values obtained in normoxia, which were set equal to 1. Each column in the panel represents the mean ± SD of 3 independent experiments. . Representative laser Doppler analysis (d) of blood flow before and 4 hours after (post 4 h) hindlimb ischemia procedure ( = 3-4 mice/group). Representative Western blot analysis and densitometric analysis (e) of MAFG and HMOX-1 protein levels performed on hindlimb muscle lysates from littermates after sham procedure (sham) or not-ischemic limb (NIL) and ischemic limb (IL) 4 h after femoral artieriectomy. Tubulin protein levels were used as loading controls ( versus sham;  = 3-4 hindlimb/group). miR-128 levels (f) were determined by RT-qPCR on total RNAs after normalization with the small RNU6. The values obtained in not-ischemic limb (NIL) were set equal to 1. The data are expressed as the mean ± standard error and are representative of 3 independent experiments. .

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