Melatonin prevents and ameliorates lead-induced gonadotoxicity through antioxidative and hormonal mechanisms

We investigated the effects of melatonin on sperm parameters and some biochemical markers in lead-exposed male Wistar rats. Lead (50 mg/kg bw/day) and/or melatonin (4 mg/kg or 10 mg/kg bw/day) was administered for 4 weeks, while 2-week lead exposure was preceded by or followed by 2-week treatment with both doses of melatonin in other groups. Lead reduced glutathione, catalase, adjusted testes weight, semen parameters but did not change malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase, and total antioxidant capacity. Though independent of prolactin, lead-induced gonadotoxicity was both centrally and peripherally mediated, as it reduced gonadotropin-releasing hormone and testosterone levels, while gonadotropin levels did not change significantly probably due to negative feedback by elevated estradiol. However, pre-, simultaneous, or posttreatment of lead-exposed rats with melatonin reduced MDA, SOD, and estradiol but dose-dependently increased other parameters. Conclusively, lead causes male gonadotoxicity through oxidative stress and endocrine mechanisms, and these could be dose-dependently prevented and ameliorated by melatonin.

The Protective Effect of Hydroalcoholic Extract of Zingiber officinale Roscoe (Ginger) on Ethanol-Induced Reproductive Toxicity in Male Rats

This study was conducted to evaluate the prophylactic effect of ginger extract on ethanol-induced reproductive toxicity in male rats. Twenty-eight adult male Sprague-Dawley rats were randomly divided into 4 groups and treated daily for 28 days as follows: control, control-ginger (1 g/kg of body weight [BW]/day by gavage), ethanol group (ethanol 4 g/kg of BW/day by gavage), and ginger-ethanol group. At the end of the experiment, all the rats were sacrificed and their testes were removed and used for measurement of the total homocysteine (tHcy), trace elements, antioxidant enzymes activity, and malondialdehyde (MDA). The results in the ethanol group indicate that ethanol decreased antioxidant enzymes activity and increased MDA and tHcy compared with the control groups ( P < .05). In ginger-ethanol group, ginger improved antioxidant enzymes activity and reduced tHcy and MDA compared to ethanol group ( P < .05). It can be concluded that ginger protects the ethanol-induced testicular damage and improves the hormonal levels, trace elements, antioxidant enzymes activity, and decreases tHcy and MDA.

Melatonin and vitamin C exacerbate Cannabis sativa-induced testicular damage when administered separately but ameliorate it when combined in rats

BACKGROUND

The mechanisms involved in the spermatotoxic effect of Cannabis sativa are inconclusive. The involvement of oxidative stress in male factor infertility has been well documented, and the antioxidative potential of melatonin and vitamin C in many oxidative stress conditions has been well reported. This study sought to investigate whether melatonin and vitamin C will ameliorate C. sativa-induced spermatotoxicity or not.

METHODS

Fifty-five (55) male albino rats (250-300 g) were randomly divided in a blinded fashion into five oral treatment groups as follows: group I (control, n=5) received 1 mL/kg of 10% ethanol for 30 days; groups IIa, IIb, and IIc (n=5 each) received 2 mg/kg C. sativa for 20, 30, and 40 days, respectively; groups IIIa, IIIb, and IIIc (n=5 each) received a combination of 2 mg/kg C. sativa and 4 mg/kg melatonin for 20, 30, and 40 days, respectively; groups IVa, IVb, and IVc (n=5 each) received a combination of 2 mg/kg C. sativa and 1.25 g/kg vitamin C for 20, 30, and 40 days, respectively; group V (n=5) received a combination of 2 mg/kg C. sativa, 4 mg/kg melatonin, and 1.25 g/kg vitamin C for 30 days.

RESULTS

Cannabis treatments reduced the Johnsen score, sperm count, motility, morphology, paired testicular/body weight ratio, and total antioxidant capacity, but increased lactate dehydrogenase activity. In addition, supplementation of cannabis-treated rats with either melatonin or vitamin C exacerbates the effect of cannabis on those parameters, whereas combination of melatonin and vitamin C reversed the trend to the level comparable to control.

CONCLUSIONS

This study further showed the gonadotoxic effect of C. sativa, which could be mediated by oxidative stress. It also showed that melatonin and vitamin C exacerbate C. sativa-induced testicular damage when administered separately but ameliorate it when combined in rats.