Reproductive toxic effects in the testes of BALB/c mice exposed to total diesel exhaust

This study used 50 male BALB/c mice divided into three groups [20 in each of test groups A and B and 10 in the control group C]. Group A and group B were exposed to total diesel exhaust [TDE]. The TDE exposures were performed in a cubic wooden box chamber [side length 50 cm] filled with TDE from a diesel fueled car. Group A was moved to the diesel filled chamber and exposed once a day for 30 minutes and group B was moved to the filled chamber and exposed once a day for 60 minutes. The control group was similarly manipulated for 60 minutes without filling the chamber with TDE. The experiment was carried out six days a week for 120 days. Four animals from group A and six animals from group B did not survive to the end of the experiment while the control animals did not have mortalities. Five of the remaining mice from each test group and 2 controls were sacrificed on the 40th day and on the 80th day. Remaining six mice in group A and four mice in group B and six mice from group C were sacrificed at the end of the experiment [120th day]. Testes and vasa efferentia were removed, testes were prepared into sections for histological, immunohistochemical staining and testicular biopsies [5 mg each] were used for Western blotting experiments to detect acrosomal proteins. Vas spermatozoa were prepared as smears for immuno-histochemical study. Down regulation of spermatogenesis reflecting structural damage of the seminiferous tubules was observed in animals sacrificed on the 40th day, this was progressive with time of exposure as seen in samples obtained on the 80th and 120th days The dependence on exposure time was also clear from comparison of sections from groups A and B, Severe oligozoospermia was detected in group A by the end of 80th days and in group B by the end of the 40th day. By the end of the experiment [120 days], the seminiferous tubules from the testes of the two test groups A and B were containing Sertoli cells only. Immunohistochemical staining of testicular sections and vas sperm suspensions using monoclonal antibodies for internal acrosomal proteins revealed a concomitant ultrastructural damage of spermatozoa in the form of defective or absent acrosome and increased proportion of abnormal sperm head morphology. The progressive decrease of sperm and spermatid -specific proteins in testicular biopsies was observed in the immuno blots. It is concluded that exposure to diesel exhaust has a massive reproductive toxicity in male mice manifested by suppression of spermatogenesis and abnormal ultra structures of vas spermatozoa. Also, the reproductive toxic effect of diesel exhaust exposure is both dose [exposure time]-dependent and duration [repeated exposures]-dependent

Cytotoxic apoptotic enhancing activities of the crude juice of an ornamental plant [Euphorbia tirucalli] on human cancer cells

Currently used Cancer chemotherapy has numerous side effects. This motivates researchers towards finding safer and clinically effective anti-cancer drugs of plant origin. We tested the milky juice of Euphorbia tirucalli [called sap or latex] after an observation of a fast irritant action on the skin and mucous membranes exposed to the sap coming out from its cut parts. Cell cultures, prepared from the fresh surgically removed human primary tumors [glioma, myelo-genous leukemia and breast cancer] were used in this study in the following number of patients 18, 26 and 20 respectively. Cell suspensions of 0.5 lamda10[5] cells/ml were maintained in RPMI-1640 culture media, and then the plant juice was added in serial dilutions to reach a final concentration of 5,10, 20, micro l per ml tissue culture. All cells were incubated for 72 hours in humidified CO2 incubator. Cells were examined at 24 hours interval for 3 days using viability test, staining with FITC [Fluorescene Iso Thio-Cynate]-conjugated anti-Caspase 9 antibodies and flow cytometry Normal white blood cells [n=20 volunteers] were used as controls to test selectivity and cytotoxicity. A significant direct selective cytotoxic action of the sap of Euphorbia tirucalli on human cancer cells compared to the controls [P < 0.001] for glioma cells, myelogenous leukemia cells and breast cancer cells. Also, similar significant effects of antimetabolite drug [methotrexate sodium] but with a more significant toxicity on normal WBCs, compared to / tirucalli sap Malignant cells responded to the sap treatments in a dose and duration dependent manner and the IC[50] [Inhibition Concentration 50] of the crude juice was found to be 10 microl of crude juice per ml tissue culture medium. Cell cycle analysis showed that the crude juice of Euphorbia tirucalli is capable of arresting the majority of cells in G[1] phase of the cell progression cycle. At the IC[50], the control cells did not show microscopically detectable change of morphology or viability. This study may introduce a new candidate plant for further studies to isolate and characterize the active, selectively cytotoxic and potentially anti-proliferative biological components in the sap of Euphorbia tirucalli