Alleviative effect of licorice on copper chloride-induced oxidative stress in the brain: biochemical, histopathological, immunohistochemical, and genotoxic study.

Although copper is an essential micronutrient involved in a variety of biological processes indispensable for sustaining life, it can be toxic when administered in excess. Licorice (Glycyrrhizaglabra) has been used in Chinese folk medicine for the treatment of various disorders. Licorice has the biological capabilities of detoxication, antioxidation, and antiinfection. Here, we test the hypothesis that licorice could ameliorate copper-induced neurotoxic and genotoxic effects in adult male albino rats. For this purpose, 48 adult male albino rats were randomized into five groups: group I (8 rats), untreated control; group II (16 rats), subdivided into; vehicle control IIa (8 rats) which received 1 mL saline twice weekly intraperitoneally for 8 weeks and vehicle control IIb (8 rats) received 0.5 mL distilled water/day orally gavaged for 8 weeks; group III (8 rats), treated with licorice dissolved in 0.5 mL of distilled water, 50 mg/kg b.w./day orally gavaged for 8 weeks; group IV (8 rats), copper chloride (CuCl2) dissolved in 0.5 mL saline, 7 mg/kg b.w. twice weekly intraperitoneal for 8 weeks; and group V (8 rats), CuCl2 + licorice (the same previously mentioned doses) licorice extract were orally given for 10 days before treatment was initiated then followed by CuCl2 intraperitoneally for 8 weeks. We found that CuCl2 exposure significantly increased brain oxidative stress as manifested by elevated malondialdehyde levels, decreased reduced glutathione content, and depressed antioxidant enzyme activities in brain tissues when compared with control groups. This was accompanied by histopathological changes in the form of increased cellularity and swelling of astrocytes that showed dense eosinophilic cytoplasm, pyknotic nuclei, and multiple apoptotic bodies that associated with degenerated neurons with deep eosinophilic cytoplasm. Also, strong Bax immunoreactions in the brain were detected. Furthermore, comet assay results confirmed CuCl2-related oxidative DNA damage. Notably, all these changes were partially ameliorated in rats treated concomitantly with licorice and CuCl2. Our results showed that licorice exerts protective effects against CuCl2-induced neuro- and genotoxicities. These effects may be attributed to the antioxidative property of licorice.

Individual and combined effect of chlorpyrifos and cypermethrin on reproductive system of adult male albino rats.

Commercial mixtures of chlorpyrifos and cypermethrin pesticides are widely used to enhance the toxic effects of cypermethrin on target insects. So, the purpose of the current study was to evaluate the individual and combined toxic effects of chlorpyrifos (CPF) and cypermethrin (CYP) on reproductive system of adult male albino rats. Forty adult male albino rats were randomized into main four groups: group I (control group) included 16 rats, subdivided into negative and positive control; group II (eight rats) received chlorpyrifos 6.75 mg/kg b.w./orally∕daily); group III (eight rats) (received cypermethrin 12.5 mg/kg b.w./orally∕daily); and group IV (eight rats) (received chlorpyrifos and cypermethrin at the same previously mentioned doses). All treatments were given by oral gavage for 12 weeks. We found that single CPF and CYP exposures significantly have adverse effects on reproductive function of adult male albino rats manifested by reduced testicular weight, decreased sperm count, motility and viability, significantly increased percent of morphologically abnormal spermatozoa, and significant increments in sperm DNA fragmentation index (DFI) with respect to control group. Furthermore, serum follicle stimulating hormone, luteinizing hormone, and testosterone levels were decreased significantly compared to control group. This was accompanied with histopathological changes in the testis of rats such as necrosis, degeneration, decreasing number of spermatogenic cells in some seminiferous tubules, edema, congested blood vessels, and exudate in interstitial tissue of the testis. Notably, all these changes were exaggerated in rats treated concomitantly with chlorpyrifos and cypermethrin rendering the mixture more toxic than the additive effects of each compound and causing greater damage on the reproductive system of male albino rats than the individual pesticides.