Effects Of Malachite Green On The Structure And Function Of Testis In Adult Mouse

ObjectivesThe present study was to investigate effects of malachite green (MG) on the pathology andultrastructure of the testis in exposed groups, so as to elucidate the characteristics of the toxicityto the testis in mouse. And aother two experiments were performed either, including thedetection of Fas/Fas-L expressed in the testis and the RAPD fingerprints of genomic DNA in thetestis, thus more message could be derived from the study about the features of the injury ofmale reproductive system caused by MG, and then to provide referential evidence for thepathogenies of male infertility.Materials and Methods1. Animals and groupingThe adult male BALB/c mice which aged 6-8 weeks and weighed 18-22g were bred instandard animal house. MG solved in normal saline was given at the same time everyday byintragastric administration. Thirty-two mice divided into four groups randomly were given MGat the dose of 0, 100, 400, or 800 mg/L in each group for 30 days consecutively in short-termexperiment, while sixteen mice divided into four groups were given MG at the dose of 0, 100,300, or 600 mg/L in each group for 90 days in long-term experiment. 2. MethodsBody, testis and epididymis were all weighed in each group. Changes of testicularmorphology were observed by light microscopy, and ultrastructure by transmission electronmicroscope. The expression of both Fas and Fas-L was detected by using immunohistochemistry.The injury of genomic DNA in testis was measured by analyzing the band intensity, differentbands, bands number of the RAPD fingerprints.Results1. The results of body weights, testis weights and epididymis weightsThe mice fed MG demonstrated a decreasing trend in the body weights, testis weights andepididymis weights. The significant reduction showed in body weights of groups D and D'(P＜0.05), in testis weights of groups C', D and D' (P＜0.01), and in epididymis weights of groupD'(P＜0.01).2. The changes of structure in testisObvious changes of testicular pathology appeared in groups C, D, B', C' and D', but not ingroup B, and the changes became more severe with the increasing dose and longer time. Thespermatogenic epithelium of testis in the exposed mouse became thinner, and there was lots ofcell slough in the lumen. Some lumens were nearly blocked by the caduceus spermatogenic cells,and the quantity of the sperm in the lumen decreased significantly.3. The changes of ultrastructure in testisMG caused the basal lamina loosen and ruffled, the cytoplasm of Sertoli cells andspermatogoniums appeared vacuoles, and the mitochondria swelled. In addition, the junctionbetween Sertoli cell and spermatogenic cell disappeared and apoptosis can be seen in theseminiferous tubules. More severe changes showed in groups of long-term experiment, whilechanges in groups of short-term experiment were not so severe.4. The expression of Fas/Fas-L in testisBoth Fas and Fas-L expressed in sperm and Leydig cells were strong while they were weakin Sertoli cells. Fas concentrated in sperm nuclei and the slough near sperm, and Fas-L locatedon sperm tails. Fas expressed in Sertoli cells and sperm increased significantly in all experiment groups except group B(P＜0.05). The positive expression of Fas-L in Sertoli cells was strongerin all treated groups than that in the control (P＜0.05).5. The changes of RAPD electrophoretogramThe injury of genomic DNA in testis was measured by analyzing the bands intensity, bandsnumber and different bands of the RAPD fingerprints in testis.The RAPD electrophoretogram oftesticular genomic DNA changed in all exposed groups, and changes became more obvious withthe increase of dose.Conclusions1. MG could cause body weights, testis weights and epididymis weights decrease more inlong-term experiment than that in short-term experiment. And the weights went down with theupgrade of the dose. It suggested that MG was harmful to the testis and the epididymis, and thedamage related to the time and dose.2. MG would have deleterious effects on testicular structures and ultrastructure of mouse,including the decrease of the layers of the spermatogenic cells, the shedding of the cells, thevacuolization of the cytoplasm of Sertoli cells and spermatogenic cells. All of that implied MGcould induce injuries of many kinds of cells in testis, and the lesions may interfere thespermatogenesis.3. MG could enhance apoptosis of germ cells by increasing Fas/Fas-L, which may weakenspermatogenesis, and lead to the decrease of fertility.4. MG would have changed the RAPD electrophoretogram of testicular genomic DNA,and that indicated MG could damage the genomic DNA in testis. The damage could induce thecancer of testis or lower the survival rate of embryo in further.