Testosterone production and spermatogenic damage induced byorganophosphorate pesticides

Parathion is an organophosphorate pesticide amply used in agriculture. Many alterations induced by organophosphorate pesticides have been described, such as: cytogenetic alterations in germinal cells, oligozoospermia and teratozoospermia in the mouse. The effect of Parathion, both pure (PP) and commercial (PC), on mouse interstitial cell testosterone production was evaluated in vivo and in vitro. Male mice were intraperitoneally injected with a single dose of 1/3 LD50 of Parathion, both PP and PC. The animals were sacrificed at 1, 8 and 40 days post injection to evaluate the impact of disrupting testosterone production on spermatogonia, spermatocytes and elongated spermatids. The plasma testosterone was assayed by standard radioimmunoanalysis. The same method was used to assay testosterone in the culture medium of interstitial cells obtained from the control and Parathion treated animals at the same time intervals. Sperm count, sperm teratozoospermia and tubular blockage were analyzed for an appraisal of spermatogenesis. Increase in the teratozoospermia and tubular blockage was detected in the PP and PC group at 8 and 40 days post injection. Plasma testosterone levels drop significantly at 8 days and recovered slowly at 40 days only in PP animals as detected in vivo, implying interference of testicular steroidogenesis due to the toxicant. Recuperation of normality occurs at long time intervals. In conclusion, Parathion disturbs the synthesis of testosterone in mice affecting qualitatively the spermatogenesis.

Morphofunctional disturbances of human sperm after incubation with organophosphorate pesticides

The organophosphorate pesticides are highly toxic for insects and mammals, but their effects in the male reproductive tract are scarcely known. Many alterations induced by organophosphorate pesticides have been described, such as: cytogenetic alterations in germinal cells, oligozoospermia and teratozoospermia in the mouse. Parathion, the pesticide mostly utilized in Chilean agriculture, is rapidly metabolized to paraoxon, the active metabolite, in mammalian organisms. The purpose of this study is to evaluate the effect of Parathion and paraoxon on different morphological and functional parameters of the sperm. Human spermatozoa were incubated with Parathion and paraoxon at different concentrations (0.05, 0.1, 0.2, 0.4 and 0.8 mM). Vitality (tripan blue and eosin tests), acrosome reaction (triple stain test), plasma membrane integrity (HOS-test), and chromatin stability (sodium thioglycolate test) were determined. The observations were done by optical microscopy at 1000x of magnification and three hundred sperms were evaluated for each treatment. The results indicated that Parathion and paraoxon increase the percent of sperm with acrosome reaction and also increase the percentage of sperm with chromatin decondensation in a dose-dependent manner. The vitality and plasma membrane integrity decrease significantly in a dose-dependent manner. The results suggest a direct action of Parathion and paraoxon on the different parameters studied. The morphofunctionality of sperm is altered significatively, suggesting that Parathion and paraoxon, thanks to their alkylating and electrophylic properties, could act on DNA and proteins respectively, to elicit these changes