Antioxidant Activity of Moringa oleifera Leaf Extract on Testicular Oxidative Stress after Experimentally-induced Cryptorchidism in Male Rats was Optimal at Low Dose

Abstract

The antioxidant properties of Moringa oleifera leaf have been found beneficial in several conditions characterized by oxidative stress. It is widely used for medicinal purposes and its consumption is unregulated. It is also known that standard antioxidant could be prooxidants at doses higher than the recommended. The present study investigated the effects of low and high doses of methanol extract of Moringa oleifera leaf (MEMO) on testicular oxidative stress and histology of cryptorchid rats. Thirty-two male Wistar rats were assigned into four groups. Group A was sham-operated and administered distilled water (p.o), groups B, C and D were bilaterally cryptorchid and orally treated with distilled water, low dose MEMO (200mg/kg) and high dose MEMO (500mg/kg), respectively. After three weeks of treatments, the left testis was obtained, weighed and assessed for histopathological variation while, superoxide dismutase (SOD) and gamma Glutamyl Transferase (GGT) activities were determined in the right testis. Testicular SOD activity reduced while GGT was increased in the cryptorchid compared with the control. Low dose MEMO-treated cryptorchid had increased SOD with reduced GGT activity compared to the untreated cryptorchid rats. At high dose of MEMO, SOD activity was significantly reduced while GGT activity increased. Testicular histology showed distorted cytoarchitecture and degeneration of germ cells in the cryptorchid rats. This was ameliorated in the low dose MEMO-treated group while there was no difference between the testicular cytoarchitecture of untreated cryptorchid and the high dose MEMO-treated rats. Thus, Moringa oleifera leaf extract at low dose ameliorated the disruption of testicular cytoarchitecture while the condition was aggravated by high dose in the experimentally-induced cryptorchid rats.