Figure 1: Decreased mitochondrial density in skeletal muscle of 16 week HFHSD mice. A: mtDNA quantity calculated as the ratio of COX1 to cyclophilin A DNA levels, determined by real time PCR, in skeletal muscle of SD and HFHSD mice, after 4 and 16 weeks of diet (n=6). Note that the y-axis scale is between 0.5 and 0.8. B: mRNA expression of mitochondria-encoded COX1 and COX3 genes, determined by real-time RT-PCR in skeletal muscle of 16 week HFHSD mice (n=6). Results were normalized by the mean value of the 16 week SD condition set to one unit. C: mitochondrial density assessed by electron microscopy, in skeletal muscle from SD and HFHSD mice, after 4 and 16 weeks of diet. D: Quantification of subsarcolemmal and intermyofibrillar mitochondria number per image area in gastrocnemius muscle of 16 week HFHSD mice (analysis of 5 images in 3 mice per group). Results were normalized by the mean value of the 16 week SD condition set to one unit. E- Citrate synthase (CS) activity in isolated mitochondria from gastrocnemius of SD and HFHSD mice, after 4 and 16 weeks of diet (n=6). * p<0.05, ** p<0.01 relative to SD mice, $ p<0.05 relative to 4 week SD mice.
