The possible protective effect of vitamin C on monosodium glutamate induced renal toxicity in male albino rats

Abstract

Introduction: Monosodium glutamate (MSG) is widely used as a food additive to improve the taste of food. Despite its taste stimulation and appetite enhancement, some reports indicated that MSG is toxic and induce an oxidative stress. Vitamin C (ascorbic acid) is a natural antioxidant that prevents the excess production of free radicals. Aim of the work: Our aim was to study the toxicological effect of MSG on the renal cortex of adult male albino rats and to evaluate the possible role of ascorbic acid as a protective agent. Materials and methods: Forty adult albino rats were divided equally into four groups. Group I was the control group; group II received ascorbic acid intraperitonial injection (500 mg/kg/day) for 4 weeks; group III rats were intraperitonial injected with monosodium glutamate (4mg/kg/day) for 4 weeks; and in group IV, rats were injected intraperitonially with ascorbic acid (500 mg/kg/day) for one week then followed by 4 weeks treated with monosodium glutamate and ascorbic acid as the same previous dose. At the end of the experiment, specimens from the kidney were taken and prepared for HandE, immunohistochemical stain and electron microscopic studies. Results: MSG induced degenerative changes in renal tubules as destruction in epithelial cell, loss of the brush border, exfoliated cellular debris in lumen of some tubules. Interstitial cells infiltration and blood vessels congestion were also noticed. There were signs of apoptosis as well as significant increase in caspase 3 antibodies expression. These changes were ameliorated by protective using of the ascorbic acid. Conclusion: MSG caused an apparent kidney injury on the histological, immumohistochemical and ultrastructure level. The ascorbic acid can ameliorate these effects.