Skip to main content
. 2024 Apr 1;56(4):922–934. doi: 10.1038/s12276-024-01199-x

Fig. 6. Restoration of Crls1 promotes muscle regeneration in the TA muscles of young and old mice.

Fig. 6

a Experimental schedule for establishing the virus-infected mouse and regeneration mouse models. b qPCR analysis of Crls1 genes in virus-infected and regenerated young TA muscle (n = 5 per group). c Viral infection and regenerated young TA muscle weight (n = 6 per group). d Histological analysis. Tissue sections from virus-infected and regenerated TA muscle was stained with anti-Laminin and H&E. DAPI, blue; laminin, red. Scale bar: 50 μm (AAV9-scramble and AAV9-shCrls1 groups were infected with AAV9 (virus diluted in PBS; total of 1×1012 GCs were injected i.m.). e Myofiber cross-sectional area (CSA) fiber percentage in scramble- and AAV9-shCrls1 virus-infected TA muscle (n = 4 per group). f Mean CSA fibers in the TA muscle (n = 4 per group). g qPCR analysis of the MyoD, Myh7, Myh4, Myh1, Cox6b, Cox7a1, Cox7a2, Cox7b and Cox8b genes in virus-infected and regenerated young TA muscle (n = 4 per group). h Experimental schedule for establishing a virus-infected mouse and a regeneration old mouse model. i qPCR analysis of Crls1 gene expression in virus-infected old TA muscle (n = 4 per group). j Viral infection and regenerated old TA muscle weight (n = 7 per group). k Histological analysis of virus-infected and regenerated TA muscle tissue sections stained with anti-Laminin and H&E. DAPI, blue; laminin, red. Scale bar: 125 µm (AAV9-GFP and AAV9-mCrls1-GFP groups) were infected with AAV9 (virus diluted in PBS; total 5×109 GCs were injected i.m.). Sectional tissue was stained with an anti-laminin antibody from AAV9-mCrls1-GFP-infected old tissue. Laminin; red, GFP; green, DAPI; blue. Scale bar = 125 µm. l Myofiber cross-sectional area (CSA) fiber percentage in AAV-GFP- and AAV9-mCrls1-GFP-infected TA muscle (n = 4 per group). m Mean CSA fibers in the TA muscle (n = 4 per group). n CSA fiber size mean of GFP- fibers and GFP+ fibers in AAV9-mCrls1-GFP virus-infected and regeneration TA muscle (n = 4 per group). o qPCR analysis of MyoD, Myh7, Myh4, Myh1, Cox6b, Cox7a1, Cox7a2, Cox7b and Cox8b in virus-infected old TA muscle (n = 4 per group). The data are presented as the mean ± SD of n ≥ 3 independent experiments. P values were calculated using an unpaired Student’s t test. *P < 0.05; **P < 0.01; ***P < 0.001; n.s.: nonsignificant. C57Bl/6j young (4 to 5 mo.) mice were used. C57Bl/6j mice aged >20 mo. mice were used.