Figure 5. The abundance of triglycerides (TGs) increases in the aged skeletal muscle mitochondria whilst the abundance of phosphatidylethanolamines (PEs) decreases. (A) 78% of TGs identified increase in abundance with ageing in the skeletal muscle mitochondria. Whilst in the skeletal muscle mitochondria 73% of PEs identified decrease in abundance with ageing. (B) Proposed pathways for the lipid changes in the young (4-11 weeks) and old (78 weeks) mitochondria. In the young mitochondria the conversion of diacylglycerols favours the production of phosphatidylethanolamine. Whilst in the old mitochondria the production of diacylglycerols to triglycerides is enhanced. Chemical structures were obtained from Kegg . (C and D) Representative scatter graphs of three triglycerides that increase in abundance in the aged skeletal muscle mitochondria. (E and F) Representative scatter graphs of the three PEs that significantly decrease in abundance in the aged skeletal muscle mitochondria (p<0.05). Scatter plots display abundance ± SEM. We used Wilcoxon rank test and Bonferroni correction (4-11 weeks n=9 and 78 weeks n=9). Refer to Supplementary Table 4.