Antifertility potentials of metronidazole in male Wistar rats

Male reproductive hormones in patients treated with pretomanid

BACKGROUND:

Pretomanid (Pa) is a nitroimidazole-class drug recently approved by the US Food and Drug Administration and other regulatory authorities as part of a regimen for treating highly drug-resistant pulmonary Mycobacterium tuberculosis infections. Studies in rodents identified the testis as a target organ of concern, which led to monitoring of reproductive hormones in >800 male patients enrolled in four clinical trials of Pa-containing regimens and the HRZE (isoniazid+rifampin+pyrazinamide+ethambutol) control regimen.

METHODS:

Serum hormone levels relevant to male reproductive health – follicle stimulating hormone (FSH), luteinizing hormone (LH), inhibin B (InhB) and total testosterone (T) – from the four clinical trials were summarized numerically and analyzed by repeated-measures modeling.

RESULTS:

Hormone levels generally behaved similarly in Pa-containing and HRZE arms. Relative to baseline, serum T and InhB levels generally increased at the end of treatment and follow-up. FSH and LH levels were variable, but were generally at or below baseline levels by follow-up. Before treatment, many patients were borderline hypogonadal, with T levels near the lower limits of the normal range.

CONCLUSION:

Changes in male hormones in four clinical trials studying patients with TB indicate that Pa-containing treatment was not associated with testicular toxicity but rather led to improvement in the underlying hypogonadism.

Thiamine deficiency and oxidative stress induced by prolonged metronidazole therapy can explain its side effects of neurotoxicity and infertility in experimental animals: Effect of grapefruit co-therapy

We aimed to explore the possible neurotoxicity and infertility mechanisms of prolonged metronidazole (MTZ) use and the effects of antioxidant grapefruit (GP) co-therapy on MTZ-induced complications. Sixty male albino Wistar rats were divided into four groups (n = 15 each). Group I (control group) received 1% dimethyl sulfoxide (27 ml/ kg/day), group II (MTZ group) received MTZ (400 mg/kg/day), group III (MTZ + GP) received MTZ (400 mg/kg/ day) plus GP juice (27 ml/kg/ day) and group IV (GP group) received GP juice (27 ml/kg) for 60 days. Semen analyses were performed. Free testosterone, gonadotrophin (follicle-stimulating hormone (FSH) and luteinizing hormone) and thiamine levels were measured. Samples of cerebellar, testicular and epididymal tissues were used for both colorimetric assays of oxidative stress markers and histopathological examinations. Significant decreases in the sperm count, percent total sperm motility, serum thiamine levels, free testosterone levels and FSH levels were observed in the MTZ and MTZ + GP groups (p < 0.05 for all parameters). Significantly higher oxidative stress levels (p < 0.05) were observed in the cerebellar and testicular tissue homogenates of these groups than in those of the control group, and associated disruptions in the cerebellar, testicular and epididymal structures were apparent compared to those of the control group. Although the GP group showed a significantly higher sperm count and significantly lower oxidative stress than the control group (p < 0.05), with histological similarity to the control group, the GP group exhibited significantly higher prolactin levels and lower free testosterone and FSH levels than the control group (p < 0.05). Oxidative stress and decreased thiamine levels could explain the MTZ-induced neurotoxicity and infertility side effects that aggravated by GP co-administration.

Nitrite-induced testicular toxicity in rats: therapeutic potential of walnut oil

Objective:

To determine the impact of walnut oil on nitrite-induced testicular toxicity in Sprague-Dawley (SD) rats. Available evidence suggests that walnut oil contains high levels of important unsaturated fatty acids including alpha-linolenic acid (ALA) and omega-3; nitrite is a reproductive toxicant that causes the loss of germ cells in the seminiferous tubules and generates oxidative stress in the testes, thus reducing sperm counts and affecting sperm morphology.

Methods:

This study included 24 male and 24 female adult SD rats. The male rats randomly assigned to Group A (controls) were given normal saline 2 ml/kg. The rats in Groups B, C, and D were given 50mg/kg body weight (bwt) of walnut oil, 0.08 mg/kg bwt of nitrite, and 0.08 mg/kg bwt of nitrite + 50 mg/kg of walnut oil respectively for 28 days via gastric gavage. Tested parameters included: testicular histology, sperm parameters, reproductive hormones, fertility, malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione, and catalase (CAT).

Results:

A severe decrease in spermatogenic cell series, hypocellularity, tubular atrophy, decreased sperm quality, and increased MDA levels were observed in the rats given nitrite only when compared to controls. Rats given 50 mg/kg of walnut oil had significant growth of seminiferous epithelium compared to controls. The rats given walnut oil and nitrite had significant growth of seminiferous epithelium, improved sperm quality, and had decreased MDA levels.

Conclusion:

Walnut oil attenuated the deleterious effects of nitrite to the testes, reduced oxidative stress, and promoted spermatogenesis.

Senecio biafrae defeated Tetracycline-Induced Testicular Toxicity in Adult Male Sprague Dawley Rats

Objective

The current study focused on the pro-fertility potential of Senecio biafrae (Sb) extract and vitamin C in Male Sprague Dawley (SD) rats with tetracycline-induced infertility.

Methods

A total of 36 male and 36 female adult SD rats were used for this investigation. The male rats randomly assigned to Group A (controls) were given normal saline 2ml/kg. Rats in Groups B, C, D, E, and F were respectively administered [30 mg/kg of body weight (bwt) of tetracycline], [30 mg/kg bwt of tetracycline + 50 mg/kg of vitamin C], [30 mg/kg bwt of tetracycline + 500 mg/kg bwt of Sb], [30 mg/kg bwt of tetracycline + 50 mg/kg of vitamin C + 500 mg/kg bwt of Sb], and [30 mg/kg bwt of tetracycline reversal] daily for 28 days via gastric gavage. Tested parameters included sperm parameters, hormonal profile, histology, and fertility test.

Results

Significant (p<0.05) increases were seen in sperm quality, hormone profile, organ and body weights of the groups treated with vitamin C, Sb, and tetracycline. There was derangement in sperm quality, hormone profile, and organ and body weight of the animals in group B. Histoarchtecture of the testes showed normal cellular composition in the germinal epithelium with sperm cells in the lumen and normal interstitium in groups A, C, D, and E. Group F showed abnormal spermatogenesis and poor association of spermatogenic cells, however there was depletion in the seminiferous epithelium in the group treated with tetracycline.

Conclusion

Senecio biafrae defeated the deleterious effects of tetracycline on the male reproductive system of rats treated with the drug.

Tribulus terrestris improves metronidazole-induced impaired fertility in the male mice

INTRODUCTION

Fruit extract of Tribulus terrestris (TT) bears aphrodisiac and antioxidative properties. Antimicrobial drug, metronidazole (MTZ) impairs the spermatogenic activity and fertility in males.

OBJECTIVE

Validation of the use of fruit extract of TT as a supplement against MTZ-induced fertility impairment in males.

METHODS

Adult Swiss strain male mice were administered with 500mg/kgBW/day of MTZ for 28 days. Low (100mg/kgBW/day) and high (200mg/kgBW/day) doses of TT were administered simultaneously with MTZ (500mg/kgBW/day) for same duration. All males were cohabited with virgin proestrus females. Vaginal plug formation was observed to calculate the libido index. Cohabited females were sacrificed on fifteenth day of gestation to dissect out the ovaries and uteri. Fertility index, quantal pregnancy, pre-implantation and post-implantation losses were calculated.

RESULTS

MTZ-treated males showed unaltered mating ability, however, the females impregnated by such males exhibited marked alterations in the fertility index, quantal pregnancy and pre- and post-implantation losses. Supplementation with low dose of TT failed to restore such reproductive toxicities exhibited by administration of MTZ. However, the altered reproductive toxicities were reinstated to control values following supplementation with high dose of TT.

CONCLUSION

The fruit extract of TT may emerge as an effective herbal remedy, correcting the drug-induced fertility impairments in males.

Tribulus terrestris ameliorates metronidazole-induced spermatogenic inhibition and testicular oxidative stress in the laboratory mouse

OBJECTIVE

The present study was undertaken to evaluate the protective effects of the fruit extract of Tribulus terrestris (TT) on the metronidazole (MTZ)-induced alterations in spermatogenesis, sperm count, testicular functions, and oxidative stress.

MATERIALS AND METHODS

Thirty adult Swiss strain mice were divided into six groups. Animals of Groups I and II served as untreated and vehicle-treated controls, while that of Groups III and IV were administered with MTZ (500 mg/kg BW/day) and TT (200 mg/kg BW/day) alone for 28 days, respectively. Low (100 mg/kg BW/day) and high (200 mg/kg BW/day) doses of TT along with MTZ (500 mg/kg BW/day) were administered for 28 days in the mice of Groups V and VI, respectively. Twenty four hours after the last treatment, all the animals were euthanized to study the histological changes in the testis and sperm count in the epididymis. Testicular functional markers, lipid peroxidation (LPO) and the activities of antioxidant enzymes, e.g., superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, were also assessed in the mice of all the groups.

RESULTS

Metronidazole caused marked alterations in the testicular weight, spermatogenesis, activities of antioxidant enzymes, lactate dehydrogenase, alkaline phosphatase, and the level of LPO. The epididymal sperm count also declined significantly in MTZ-treated group. These changes were partially restored following co-administration of 500 mg/kg BW/day of MTZ and 100 mg/kg BW/day of TT. However, in the mice co-administered with 500 mg/kg BW/day of MTZ and 200 mg/kg BW/day of TT, the changes reverted back completely, similar to that of the controls.

CONCLUSION

The fruit extract of TT ameliorates the MTZ-induced alterations in the testis.