Duration-Dependent Histopathological and Histometric Changes in the Testis of Aflatoxin B1-Treated Mice

In the background of the decreasing trend of male reproductive health in men and animals, the present study was aimed at finding gravimetric, histopathologoical and histometric changes in the testis of Swiss mouse in response to treatment of aflatoxin B₁ (AFB₁) in a chronic toxicity testing over different periods of time and at finding recovery, if any, after cessation of the treatment. AFB₁ suspended in corn oil and ethanol, was administered through intraperitoneal route to 90 day old Swiss mouse at a daily dose of 50mg/kg body weight for 7, 15, 35, 45 days. In the recovery group the mice were kept, after cessation of the treatment, under observation for 35 or 70 days. The testicles and seminal vesicles of the animals were subjected to histopathological analysis adopting paraffin/resin embedding and light microscopy. Computer assisted histometric analysis of several parameters was also made. In general there was little impact of the treatment in the animals treated for 7 days. In the animals treated for 15, 35 and 45 days, there was duration-dependent regression of the testis and seminal vesicles. Histopathological changes were observed in both the spermatogenic and androgenic compartments of the testis. Fragmentation of chromatin of pachytene spermatocytes, generation of uni- and multinucleate gaint cells, and premature loss of spermatids and spermatocytes were observed. Whereas the seminiferous tubules regressed, the Leydig cells underwent hypertrophy and distortion of shape of the nucleus. Generation of multiple micronucleate gaint cells and extensive loss of germ cells from the seminiferous epithelium were observed. Fertility of the mice was severely hampered. The various changes are discussed in relation to the possible effects of AFB₁ on the microtubules of the spindle fibers and the DNA of chromatin. Since spermatogonia and Sertoli cells are not vulnerable targets to AF toxicity, the treated animals recovered over a period of time.