Expression of leptin mRNA in luteinized granulosa cells and leptin levels in serum and follicular fluid of non-obese infertile patients with polycystic ovary syndrome

Abstract

To investigate the expression of leptin mRNA in luteinized granulose cells and the leptin level in serum and follicular fluid of non-obese patients with polycystic ovary syndrome (PCOS). Granulosa cells were collected from the puncture fluid of follicle of 16 obese infertile patients with PCOS to undergo external fertilization. Fasting venous blood was collected while collecting the ova. RT-PCR was used to detect the expression of leptin mRNA in the granulosa cells. ELISA was used to detect the leptin level in the serum and follicular fluid. Twenty normal women undergoing external fertilization because of male infertility of their husbands were used as controls. The expression of leptin mRNA (A value) was 1.5 +/- 0.4 in the obese infertile patients with PCOS and was 1.8 +/- 0.6 (P > 0.05) in the controls. Both the leptin levels of serum and follicular fluid were not different between the obese infertile patients with PCOS and controls (both P > 0.05). The leptin level in follicular fluid was significantly correlated with both the serum leptin level in the obese infertile patients with PCOS (r(s) = 0.838, P = 0.000) and the control group (r(s) = 0.712, P = 0.000). The expression level of leptin mRNA in the luteinized was not correlated with the leptin level of follicular fluid in both the obese infertile patients with PCOS and the control group (both P > 0.05). The fertility rate was not different between the obese infertile patients with PCOS (7/16) and the controls (9/24) (P = 0.693). The expression of leptin mRNA is normal in the follicular fluid of the obese infertile patients with PCOS. The leptin levels in serum and follicular fluid of the obese infertile patients with PCOS are similar to those of normal women. The leptin level in follicular fluid depends mainly on the circulating leptin level.