Effect of the hydroalcoholic extract of melon seeds (Cucumis melo L.) on the pituitary-gonadal axis and testicular tissue changes in adult male rats

Melon seeds have estrogenic, anti-cancer, anti-diabetic, anti-obesity, and antioxidant effects. The present study aimed to investigate the effect of the hydroalcoholic extract of melon seeds on the pituitary-gonadal axis and the tissue changes of the testis in adult male rats.

In this experimental study, 50 adult male Wistar rats weighing 210-230 g were assigned to five groups (n=10). The Control group received no extract or solvent; Sham group: 1 ml of distilled water as a solvent; experimental group 1: Melon seed extract (50 mg/kg), experimental group 2: Melon seed extract (100 mg/kg), Experimental group 3: Melon seed extract (150 mg/kg). After 21 days of treatment by the intraperitoneal method, blood was taken from the animals. The serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone were measured by radioimmunoassay (RIA). Thereafter, the testicles were removed, and tissue changes were examined by hematoxylin-eosin staining. The collected data were analyzed in SPSS software (version 18) using a one-way analysis of variance and post hoc Tukey's test.

The mean body weight in experimental groups 2 and 3 demonstrated a significant decrease compared to the control and sham groups (P<0.001). The mean weight of the testes in experimental groups 2 and 3 displayed a significant increase compared to the control and sham groups. The mean concentration of testosterone hormones, FSH, LH, the number of spermatogonial cells, primary spermatocytes, spermatids, Sertoli, and Leydig cells, as well as the number of sperm cells in experimental group 3,  had a significant increase compared to the control and sham groups (P<0.001).

As evidenced by the results of this study, the hydroalcoholic extract of melon seeds had stimulating effects on the pituitary-gonadal axis and testicular tissue in adult male rats.