Relationship between synthesis of P21 and Cyclin D1 proteins and histomorphometric parameters of mice testicular tissue in presence of Aflatoxin G1

AFG1 after B1 is the most important aflatoxin found in beans and grains. Remarkably, aflatoxin cause a decrease in production and quality of sperm. In the current study, the effect of AFG1 on spermatogenesis, spermiogenicity, synthesis of P21 and cyclin D1 proteins in testicular tissue was investigated. 24 male albino mice were divided into 4 groups; control group intraperitoneally received 0.2 ml corn oil and experimental groups received AFG1 (20 μg) for 7, 15, and 35 days, respectively. After 7, 15 and 35 days, the testicular tissue samples were taken, and after preparing tissue sections, hematoxylin and eosin (H&E) staining was performed. Histomorphometric parameters and the immunohistochemical analysis of proteins of P21 and cyclin D1 were investigated. Data analysis was carried out using one-way ANOVA at the significance level of p<0.05. The results of this study showed that the diameter of the spermatozoa tubes and the thickness of the germinal epithelium in the experimental groups significantly decreased (P <0.05), which was time dependent. The percentage of semen tubes with differentiation coefficients, tubular replacement as well as negative spermiogenesis increased in mice receiving AFG1. Conspiciously, injection of AFG1 in experimental group mice resulted in increased synthesis of P21 and cyclin D1 proteins. AFG1 interrupted cell division by increasing the amount of protein synthesis of Cyclin D1 and P21 protein, which in turn could be a disorder in the process of spermatogenesis. However, increase differentiation indices, tubular differentiation, and spermiogenesis in testicular tissue, which consequently lead to a decrease in sperm production and quality.