Phyllanthus amarus protects against potassium-dichromate pituitary toxicity via the oxidative pathway and improves the gonadotropins in male Wistar rats

Background. Phyllanthus amarus is an antioxidant plant with numerous beneficial biological activities, but scarce information on its neuroprotective role against potassium dichromate (PDC)-induced neurotoxicity. This research investigated the antioxidant effect of aqueous Phyllanthus amarus leaf extract (APALE) on PDC-induced rats. Materials and methods. Fifty male Wistar rats (120-130g) were randomized into five groups (A-E, n=10). Group A: (Control) distilled water; B: 300mg/kg APALE; C: 17mg/kg PDC; D: 17mg/kg PDC + 400mg/kg APALE; E:  17mg/kg PDC + 200mg/kg APALE. Administrations were once daily via an orogastric cannula for 28 consecutive days.  At the end of the experiment, blood samples were obtained for hormonal assay (FSH and LH). The animals were euthanized, and pituitary glands were harvested and homogenized for Superoxide Dismutase (SOD) and Catalase (CAT), Glutathione Reductase (GSH) by x-ray crystallography, Malondialdehyde (MDA) by thiobarbituric acid reacting substances (TBARS) and paraffin embedding sections, for histological and histochemical evaluations. Results. Morphometric analysis revealed that PDC caused a reduction in body and brain weights, volume, and weight of the pituitary gland.  Masson trichrome demonstrates excessive accumulation of collagen fibers on PDC-treated tissues resolved by APALE.  There was a significant increase in MDA in the PDC group and a decrease in the APALE groups compared to the control.  In APALE groups, the SOD, CAT, GSH, and T-Protein levels significantly increased compared to the control group. PDC significantly decreased LH and FSH levels compared to the control. However, APALE restored these changes. Conclusions. APALE demonstrated potent protective activity against PDC-induced pituitary toxicity.