Apolipoprotein E-containing HDL-associated platelet-activating factor acetylhydrolase activities and malondialdehyde concentrations in patients with PCOS

PAF and PAF-like oxidized phospholipids hydrolysed by platelet-activating factor (PAF) acetylhydrolase (AH) are potent lipid mediators involved in inflammation and atherosclerosis. Apolipoprotein (apo) E-containing high-density lipoprotein (HDL) has antioxidant, anti-inflammatory and anti-atherogenic properties. The study investigated apoE-containing HDL-associated PAF-AH (HDL-PAF-AH) and total (apoE-containing + apoE-poor) HDL-PAF-AH activities as well as malondialdehyde (MDA) concentration in 291 patients with polycystic ovary syndrome (PCOS) using the Rotterdam consensus criteria and 281 control women. Compared with the control women, patients with hyperandrogenism + oligo/anovulation + polycystic ovaries (PCO) or hyperandrogenism + PCO had lower total, apoE-containing and apoE-poor HDL-PAF-AH activities, while those with oligo/anovulation + PCO showed decreased total and apoE-poor HDL-PAF-AH activities. Other factors including insulin resistance and obesity in PCOS had the adverse effects associated with the HDL-PAF-AH activities. Serum MDA concentration was associated with PCOS, hyperandrogenism, insulin resistance and hypertriglyceridaemia in patients with PCOS. Decreased total and apoE-containing HDL-PAF-AH activities and increased serum MDA concentration may contribute to the pathogenesis of PCOS and potentially link to related complications responsible for oxidative stress and inflammation such as an increased risk for type 2 diabetes mellitus and/or future cardiovascular diseases in PCOS patients.Platelet-activating factor (PAF) acetylhydrolase (PAF-AH) hydrolyses and inactivates PAF and PAF-like oxidized phospholipids that are potent lipid mediators involved in inflammation and atherosclerosis. Apolipoprotein (apo) E-containing high-density lipoprotein (HDL) has antioxidant, anti-inflammatory and anti-atherogenic properties. The study investigated apoE-containing HDL-associated PAF-AH (HDL-PAF-AH) activities, total (apoE-containing + apoE-poor) HDL-PAF-AH activities as well as malondialdehyde (MDA) concentration in 291 patients with polycystic ovary syndrome (PCOS) using the Rotterdam consensus criteria and 281 control women. Our results reported for the first time, as far as is known, that the apoE-containing HDL has a relatively high PAF-AH activity and accounts for about 50% of total HDL-PAF-AH activity in both the patient and control groups. Compared with the control women, the patients with hyperandrogenism + oligo/anovulation + polycystic ovaries (PCO) or hyperandrogenism + PCO had lower total, apoE-containing and apoE-poor HDL-PAF-AH activities, while those with oligo/anovulation + PCO showed decreased total and apoE-poor HDL-PAF-AH activities. Other factors, including insulin resistance and obesity in PCOS, had adverse effects associated with the HDL-PAF-AH activities. Serum MDA concentration was associated with PCOS, hyperandrogenism, IR and hypertriglyceridaemia in patients with PCOS. Since HDL-PAF-AH activity has been consistently shown to play an anti-inflammatory and anti-atherogenic role, the decreased total and apoE-containing HDL-PAF-AH activities and increased serum MDA concentration may contribute to the pathogenesis of PCOS and potentially link to related complications responsible for oxidative stress and inflammation, such as an increased risk for type 2 diabetes mellitus and/or future cardiovascular diseases in PCOS patients.