Figure 7.

miR-127 ameliorates the dystrophic phenotype of mdx mice. (a) Fold overexpression of miR-127-3p in mdx;miR-127 mice, determined by quantitative real-time polymerase chain reaction (qRT-PCR). The data were normalized using U6. miR-127 expression levels were further normalized to the expression level of WT, defined as 1. (b) S1PR3 mRNA levels in mdx;miR-127 mice, determined by qRT-PCR. The data were normalized using GAPDH. S1PR3 expression levels were further normalized to the expression level of WT, defined as 1. (c) Serum CK levels in WT, miR-127 TG, mdx, and mdx;miR-127 mice at 3 month of age. (d) EBD uptake in TA muscles of mdx and mdx;miR-127 mice at 3 month of age. EBD was detected as a red signal under a fluorescence microscope. Laminin immunostaining is shown in green. Scale bars, 100 μm. (e) The percentages of EBD⁺ fiber areas in TA muscles from mdx and mdx;miR-127 mice. (f) Representative images of EBD⁺ areas in quadriceps muscles of mdx and mdx;miR-127 mice at 3 month of age. EBD was detected as a red signal under a fluorescence microscope. Laminin immunostaining is shown in green. Scale bars, 100 μm. (g) The percentages of EBD⁺ fiber areas in quadriceps (QU) muscles from mdx and mdx;miR-127 mice. (h) Cross-sectional areas of myofibers with centralized nuclei in TA muscles from mdx and mdx;miR-127 mice (n=5 mice per group). (i) Three-month-old WT, miR-127 TG, mdx, and mdx;miR-127 mice were subjected to forced downhill running on a treadmill. Muscle performance was measured as total running time to exhaustion. (j and k) EDL muscles isolated from WT, miR-127 TG, mdx, and mdx;miR-127 mice were electrically stimulated in vitro to elicit tetanic contractions. Maximal twitch force (j) and peak tetanic forces (k) were determined. Values are presented as means±S.E. (n=5 mice per genotype). *P<0.05; **P<0.01 and ***P<0.001