Fig. 7

Mechanical stretching increases the number and activity of mitochondria in MscL-G22S-activated SCs. A-B The mitochondria in SCs were stained with MitoTracker Green (Scale bars = 5 μm). As indicated, there was significantly higher mitochondrial intensity, indicating the greater number of mitochondria, in MscL-G22S-activated SCs. C-E The data of electron microscopy showed significantly greater mitochondrial length and area in MscL-G22S-activated SCs than the controls (Scale bars = 2 μm). F-G Mitochondrial membrane potential (MMP) in SCs was measured by JC-1 staining to evaluate the mitochondrial activity (Scale bars = 50 μm). JC-1 aggregates indicate high MMP while the JC-1 monomer indicates low MMP. Quantification analysis of the ratio of JC-1 aggregate/monomer showed significantly increased mitochondrial activity in MscL-G22S-activated SCs than the controls. H a schematic diagram annotates the effects of mechanical stimuli on the mitochondrial respiration of MscL-G22S-expressing SCs, including upregulated expression of ETC complexes, greater mitochondrial number, area, and MMP as well as the increased production of ATP. The data shown were representative of four independent experiments. At least 10 visual fields of cultured SCs with different treatments were captured for each biological replicate. NC, negative control; MscL, MscL-G22S-expressing SCs; NC-stretch, negative control with mechanical stretching; MscL-stretch, MscL-G22S-expressing SCs with mechanical stretching. ns, not significant, *p < 0.05, **p < 0.01, ***p < 0.001