Sex differences in serum pigment epithelium-derived factor in healthy individuals

To investigate sexual dimorphism of serum pigment epithelium-derived factor (PEDF) and its influencing factors in healthy individuals. A total of 162 healthy people (69 males, 93 females) who underwent health examinations in our department were selected. Serum PEDF, estradiol and other metabolic indices were measured, and homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β) were calculated to evaluate insulin resistance and β-cell function, respectively. Subjects were divided into < 50 years and ≥ 50 years groups to explore the sexual dimorphism of serum PEDF in different age groups. We found no statistically significant difference in serum PEDF levels between men and women in total. However, in the group of subjects under 50 years old, men had significantly higher PEDF levels than women (9.32 ± 2.07 μg/mL vs 8.24 ± 2.29 μg/mL, P < .05), and no sex difference was found in the ≥ 50 years group. In women, serum PEDF levels were significantly higher in subjects aged 50 years and over than in those younger than 50 years of age (9.56 ± 3.05 μg/mL vs 8.25 ± 2.30 μg/mL, P < .05). In men, there was no significant difference in serum PEDF levels between the 2 age groups. In women, correlation analysis showed that serum PEDF levels were significantly correlated with body mass index, waist circumference, diastolic blood pressure (DBP), 2-h postprandial glucose, fasting and 2-h postprandial insulin, HOMA-β, HOMA-IR, aminotransferase, triacylglycerol, and estradiol. Elevated triacylglycerol and aminotransferase and decreased estradiol were significant predictors of increased PEDF concentrations in women. There is sexual dimorphism in circulating PEDF levels, which may be related to estrogen status.