Developmental deficits in male rat pups caused by maternal and dietary administration of chlorpyriphos and cypermethrin: Melatonin's mitigating effect.

The ability of melatonin to reduce growth inadequacy induced by parental and nutritional combination administration to chlorpyriphos (Ch) and cypermethrin (Cy) was examined in male albino rats. Oral alimentation was given to gravid dams divided into six groups (n = 10; age: 12 weeks) from the first day of pregnancy to the 21st postnatal day. Distilled water (DW), Soya oil (SYO), and melatonin (MeL) groups were exposed to 2 mL/kg, 2 mL/kg, and 0.5 mg/kg, respectively; the Ch+Cy group was co-exposed to Ch (1.9 mg/kg of LD50) and Cy (7.5 mg/kg of LD50); the MChCy group was preconditioned with MeL (0.5 mg/kg), followed by co-exposure to Ch and Cy; and the ChCyM group was exposed to Ch and Cy and post treated with MeL. Male offspring rats were tested for ontogeny criteria at various points after accouchement. MeL pre- and post-administration reduced the variation in litter size and weight, number of live/dead pups, anogenital distance , crown-rump length, the timing of eye and ear openings, and testicular descent caused by fetal and nutritional co-administration to Ch+Cy in offspring male albino rats. MeL demonstrated preventive promise as a result of its apparent antioxidative capability.

Taurine ameliorated thyroid function in rats co-administered with chlorpyrifos and lead.

Chlorpyrifos is a widely used organophosphate insecticide for domestic, agricultural and industrial purposes. Lead is a toxic heavy metal and it is used for domestic and industrial purposes. Taurine is a semi essential amino acid with bioprotective properties. The aim of this study was to investigate the effects of taurine on thyroid function in Wistar rats co-administered with chlorpyrifos and lead. The rats were divided into 5 groups of 10 rats each. The first two groups were administered with distilled water and soya oil (1 ml/kg) respectively. The other groups received taurine (50 mg/kg), chlorpyrifos + lead [chlorpyrifos (4.25 mg/kg, 1/20 median lethal dose] and lead (233.25 mg/kg, 1/20 median lethal dose) and taurine + chlorpyrifos + lead respectively. The treatments were administered once daily by oral gavage for 16 weeks. The rats were euthanized after the completion of the study and the thyroid function and thyroid histoarchitecture were evaluated. The results revealed that co-administration of chlorpyrifos and lead to the rats induced perturbations in thyroid function and this was manifested by reductions in the concentrations of triiodothyronine and thyroxine, increased thyroid stimulating hormone concentration and degeneration of the follicular epithelia of the thyroid gland. Taurine alleviated the perturbations in thyroid function and improved thyroid gland histoarchitecture. The beneficial effects of taurine may be attributed to its ability to protect the body from toxicity and oxidative stress. Taurine may be useful for prophylaxis against disruptions in thyroid function in animals that are exposed to environmental chlorpyrifos and lead.