The Protective Effect of Galangin on Histopathological Lesions, Immunohistochemical Findings and Spermatological Parameters in Phthalate-Induced Testicular Damage in Rats

Abstract

One of the main causes of the increasing male infertility today is di-(2-ethylhexyl) phthalate (DEHP), which is widely used in plastic production. To investigate testicular damage caused by DEHP and the effect of galangin, used for the first time in this treatment, the protective effect of different doses of galangin on testicular damage induced by administering DEHP for 14 days to 54 Sprague Dawley rats aged 8-10 weeks was examined. For this purpose, experimental groups were designed as follows: (Control: no treatment applied, Solvent: 5 mL/kg/day corn oil applied, Phthalate (PHT): 2 g/kg DEHP applied, Galangin GL-5, GL-10 and GL-15: galangin applied at doses of 5, 10 and 15 mg/kg, respectively, PHT + GL-5, PHT + GL-10 and PHT + GL-15: galangin applied at doses of 5, 10 and 15 mg/kg, respectively, 1 h after 2 g/kg DEHP dissolved in 5 mL/kg corn oil). After the experimental process was completed, histopathological and immunohistochemical analyses were performed on tissue samples taken from decapitated rats. Malondialdehyde (MDA), reduced glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) analyses were performed on tissue and serum samples, and spermatological analyses were also conducted. In the PHT group, changes in light microscopic findings in the testes (degeneration in seminiferous tubules, interstitial oedema, interstitial vascular hyperaemia) and a decrease in Johnsen scoring, seminiferous tubule diameters and epithelial thickness were observed. It was determined that galangin administration, with increasing doses, led to significant improvements in histopathological parameters. When the immunoreactivity of Hydroxy-Delta-5-Steroid Dehydrogenase, 3 Beta- and Steroid Delta-Isomerase 1 (HSD3B1), and the sex-determining region Y-box 9 (Sox9) was examined in testicular tissues, a decrease was observed in the PHT groups and an increase in the GL groups. In the PHT group, plasma and testicular tissue MDA levels were higher compared to the control and other groups, while GSH, CAT, GSH-Px, SOD and GST levels were lower. In the GL groups, the opposite effect was observed in these parameters compared to the PHT group. In spermatological analyses, it was observed that the negative effects in some parameters (gonado-somatic index [GSI], density, total motility, acrosomal damage rate, mitochondrial membrane potential, morphological values) observed in the PHT groups decreased and disappeared in a dose-dependent manner in the galangin-treated groups. This study confirmed that galangin improved testicular damage caused by DEHP exposure, providing strong evidence for the use of galangin in the treatment of DEHP-related infertility.