FIGURE 6.

Summary of altered metabolites and metabolic pathways in this study. The metabolome of liver tissue and hepatic exosomes in PCOS between young (YP, left green part) and middle age (MP, blue right part) are compared. The common alterations of the two age groups are downregulation of glycolysis and TCA cycle, as well as upregulation of gluconeogenesis. The major substrates for gluconeogenesis in YP and MP hepatic cells are fatty acids and amino acids, respectively (purple boxes). In YP hepatic cells, the urea cycle, protein digestion and pyrimidine metabolism seem to be upregulated, while the glutathione metabolism seems to be upregulated in MP hepatic cells. The arrows indicate up- or down-regulation of metabolites in (green) young- or (blue) middle-age groups detected in the liver or exosomes. The purple dotted lines indicate the gluconeogenesis pathway in hepatic cells. The red dotted lines indicate the processes in which the elevated metabolic products are transported into exosomes.