Figure 3

Metabolic pathways associated with polycystic ovary syndrome (PCOS) development. The schematic map was modified from [17], with permission from the American Chemical Society (copyright (2007)). Amino acid metabolic pathways are grouped according to their points of entry into the tricarboxylic acid (TCA) cycle, glycolysis, ketogenesis, lipolysis, proteolysis and urea cycles. Glucogenic amino acids can be broken down into one of the following metabolites: pyruvate (Ala, Ser, Thr, Try, Gly, Cys), α-ketoglutarate (KGA) (Pro, Arg, His, Glu, Orn, Cit), succinyl CoA (Val, Thr, Ile, Met), fumarate (Phe, Tyr) or oxaloacetate (OAA) (Asp); while ketogenic amino acids can be broken down into acetoacetyl-CoA (Phe, Tyr, Trp, Lys, Leu) or acetyl-CoA (Ile, Leu, Try). The increase (red) and decrease (blue) of metabolites concentrations in the PCOS plasma were on the basis of both our data and previous report (reduction of arginine and citrate in PCOS patients [19]). The glycolysis, lipolysis and proteolysis pathways were induced in women with PCOS, whereas the TCA cycle and ketogenesis were inhibited in PCOS. Fatty acids included linoleic acid, palmic acid and stearic acid. Amino acids are abbreviated using the standard three-letter convention. AA = amino acids; ACAC-CoA = acetoacetyl-CoA; ASA = argininosuccinate.