Background and Objective: Sex hormone levels decrease in ovarian aging, causing follicular cysts and low levels of the ovarian albumin/epidermal growth factor receptor (EGFR). L-arginine, a nitric oxide (NO) precursor, plays a role in preventing ovarian aging. We intended to show whether chronic L-arginine consumption has anti-aging benefits on the ovary.
Materials and Methods: Wistar rats (250 g, 36 weeks) were divided into two groups (control and experimental). The control group received 1 mL/kg saline intraperitoneally (i.p.). The experimental group received L-arginine (5, 25 and 50 mg/kg) and L-NAME (5 and 25 mg/kg) alone or together for 3, 5, 9 and 21 days, once a day. At the end, blood samples were taken from rats under deep anesthesia, and serum albumin levels were measured using an ELISA kit. The ovaries were then surgically removed and subjected to biometric, histopathological (Hematoxylin-Eosin and Evans blue) and immunohistopathological tests for EGFR. All data were analyzed using analysis of variance (ANOVA) at α=0.05.
Results: L-arginine reduced the number of follicular cysts in the shortest period (3 days) at the lowest dose (5 mg/kg) and improved serum and ovarian albumin levels as well as EGFR levels in ovaries compared to treatment with L-NAME/L-arginine. These phenomena indicate the involvement of NO. High-dose L-arginine (regardless of duration) increased the number of follicular cysts. Weight change was not statistically significant.
Conclusion: L-arginine in short periods and with low concentration can reduce ovarian aging problems by increasing the level of NO.