The mammalian testis accumulates lower levels of organochlorine chemicals compared with other tissues

Impact of dieldrin on liver morphological and biochemical parameters of rats

The current study deals with the effect of the organochlorine insecticide on the liver of Wistar rats. The dieldrin effect on rats was tested after a single intraperitoneal (i.p.) injection of two doses: 3 and 6 mg/kg and observations were made 4 days later. Animals showed a significant dose-dependent increase in relative liver weight. Elevations of transaminases (aspartate aminotransferase [AST], alanine aminotransferase [ALT]), bilirubin and total activity of lactate dehydrogenase (LDH) were recorded in the sera of treated rats. Serum LDH-5 isoenzyme activity increases in a dose-dependent manner. In contrast, LDH-1 activity does not show any significant variations with respect to controls. Histological examination of the liver of dieldrin-treated animals revealed cytoplasmic vacuolation, focal necrosis and nuclear enlargement of hepatocytes. This study suggests that biochemical assessment (transaminases, LDH and bilirubin activity) and LDH (LDH-1 & LDH-5) isoenzyme profiles can be very helpful in defining the border of the liver injury, dieldrin damaged liver would be a valuable addition to histological analysis in evaluating histopathological liver changes.

Systemic dermatological treatment with relevance for male fertility

The dermatologist employs systemic agents with likely gametotoxic side effects, including cytotoxic, immunosuppressive, immunomodulatory and biological agents. The impact of chemotherapy on male fertility depends on the treatment protocol as well as the pre-treatment spermatogenesis status. Sperm concentration starts to drop about 2 weeks after beginning chemotherapy and reaches a maximum after 2-3 months. About half show recovery after 12-36 months. One year after therapy is completed, a treated patient has no increased risk of fathering a malformed child. There are no reports of methotrexate patients fathering children with malformations, most likely because impaired fertility or embryogenesis arrest. Cryopreservation of male gametes should be recommended prior to cytotoxic treatment, since the likelihood of post-treatment fertility is unpredictable. The cryopreservation causes a loss of vital spermatozoa by 30-70% but does not influence the genetic information of gametes. Males treated with retinoids have no reproductive safety risk. Biologicals inhibiting TNF alpha show a positive effect on sperm function in vitro.

In vitro alachlor effects on reactive oxygen species generation, motility patterns and apoptosis markers in human spermatozoa

Due to its extensive production and application, the toxicity of chloracetanilide herbicide alachlor[2-chloro-2',6'-diethyl-N-(methoxymethyl)-acetanilide] should be evaluated to establish minimum effects. In this study, we have examined the in vitro effects of alachlor on human sperm motion using a computer-assisted sperm analyser (CASA). An evaluation of both reactive oxygen species (ROS) and markers of apoptosis was also performed to investigate the mechanism by which alachlor modifies the sperm movement. After exposure up to 2 h to alachlor (0, 0.18, 0.37, 0.90 and 1.85 mM), the percentage of viable, motile spermatozoa and sperm velocities were concentration and/or time dependently decreased. The most sensitive parameters were progressive motility, mean average path velocity and mean straight velocity. Alachlor (1.85 mM) induced an increase in ROS production. A decrease of mitochondrial membrane potential (DeltaPsi(m)), an increase of both phosphatidylserine (PS) externalization and DNA fragmentation, which were concentration and/or time dependent, were also observed. It is possible that toxic effects of alachlor result in an oxidative stress which could act as a mediator of apoptosis. Alachlor could also contribute to some hypofertility cases.

Alkyl phenols and diethylhexyl phthalate in tissues of sheep grazing pastures fertilized with sewage sludge or inorganic fertilizer

We studied selected tissues from ewes and their lambs that were grazing pastures fertilized with either sewage sludge (treated) or inorganic fertilizer (control) and determined concentrations of alkylphenols and phthalates in these tissues. Mean tissue concentrations of alkylphenols were relatively low (< 10-400 microg/kg) in all animals and tissues. Phthalates were detected in tissues of both control and treated animals at relatively high concentrations (> 20,000 microg/kg in many tissue samples). The use of sludge as a fertilizer was not associated with consistently increased concentrations of either alkylphenols or phthalates in the tissues of animals grazing treated pastures relative to levels in control animal tissues. Concentrations of the two classes of chemicals differed but were of a similar order of magnitude in liver and muscle as well as in fat. Concentrations of each class of compound were broadly similar in tissues derived from ewes and lambs. Although there were significant differences (p < 0.01 or p < 0.001) between years (cohorts) in mean tissue concentrations of both nonylphenol (NP) and phthalate in each of the tissues from both ewes and lambs, the differences were not attributable to either the age (6 months or 5 years) of the animal or the duration of exposure to treatments. Octylphenol concentrations were generally undetectable. There was no consistent cumulative outcome of prolonged exposure on the tissue concentrations of either class of pollutant in any ewe tissue. Mean tissue concentrations of phthalate were higher (p < 0.001) in the liver and kidney fat of male compared with female lambs. We suggest that the addition of sewage sludge to pasture is unlikely to cause large increases in tissue concentrations of NP and phthalates in sheep and other animals with broadly similar diets and digestive systems (i.e., domestic ruminants) grazing such pasture.

Smooth muscle actin and vimentin as markers of testis development in the harbour porpoise (Phocoena phocoena)

Testicular development in the harbour porpoise Phocoena phocoena was examined using animals (n = 192) stranded or by-caught off the coast of England, Wales and Scotland. Classification of animals according to their stage of sexual development was undertaken using gonadal morphology and the distribution of cytoskeletal proteins. Smooth muscle actin (SMA) and vimentin proved particularly useful in this respect; SMA was prominent in the myoid peritubular cells of the adult testis, and two stages of peritubular cell SMA expression could be recognized ('absent' or 'incomplete'). The initial appearance of SMA in peritubular cells was associated with significant increases in body length and body weight (P < 0.001), and occurred during the second year of life. Vimentin, which was prominent in prespermatogonia and spermatogonia, sometimes showed a polarized cytoplasmic distribution. This correlated with a developmental stage at which the seminiferous tubule epithelium becomes populated by germ cells (mean age 1.8 years). Several antibodies were tested for their utility as Sertoli cell markers, but none was found to be specific or useful. Nevertheless, immunohistochemical localization of desmin, GATA-4, Ki67 and androgen receptor was possible despite the poor quality of tissue preservation. This study showed that immunohistochemical classification of these individuals provides a robust basis for the recognition of key physiological stages of sexual development in the male harbour porpoise. This may provide an alternative to the estimation of age, body weight and body length in future analyses aimed at detecting possible adverse effects of environmental pollutants on the reproductive potential of wild marine mammals.

The presence of environmental pollutants in the semen of farm animals (bull, ram, goat, and boar)

Organochlorine pesticides and polychlorinated biphenyls are widely used in agriculture and industry, respectively, and may affect male reproduction function. Although several pollutants have been detected in human semen, similar studies in farm animals have not appeared. In the present study, the semen of bulls, rams, goats, and boars was assayed for the organochlorine pesticides hexachlorobenzene (HCB), hexachlorocyclohexane (HCH, alpha-, beta-, and gamma-isomers), dieldrin, and heptachlor epoxide, for DDT-related chemicals (o,p'-DDE, p,p'-DDE, p,p'-DDD, p,p'-DDT), and for the PCBs congeners (PCB-52, -101, -138, -150, and -180). In all species of farm animals, the most frequently detected pollutants were p,p'-DDE (80-100% of samples), HCB (73.9-100%), and gamma-HCH (69.6-100%). Species differences in the concentrations of HCB, alpha-, beta-, and gamma-HCH, dieldrin, p,p'-DDE, p,p'-DDD, and PCBs were noted as well as differences in the concentrations of some isomers of HCH, DDT-related chemicals, and PCB congeners in the same species.