Toxicity of monosodium glutamate on liver and body weight with the protective effect of tannic acid in adult male rats

Abstract

One of the food additives that are used extensively in the food industry is monosodium glutamate which has a flavor enhancer that is considered a doubleedged sword on human health. Tannic acid (TA) is a natural antioxidant that works against many toxic substances. The current study aimed to evaluate the toxicity of MSG on rat liver with a possible protective role of TA. Forty adult male albino rats were used. They were divided into 4 equal groups, 10 rats each. Group, I was the control group, Group II received TA (100 mg/kg) by oral gavage, Group III received MSG (2 g/kg) by oral gavage and Group IV received (TA and MSG) by oral gavage for 4weeks. At the end of the study, biochemical analysis was done and revealed that Group III showed a significant increase in the body weight and significant elevation in the serum levels of ALT and AST enzymes compared to group I with p > 0.001. While, there was a non-significant difference in relative liver weight with p> 0.05. Histopathological examination revealed that group III showed a severe complete loss in hepatic architecture such as congestion and dilatation in the blood vessels with different cellular changes such as necrosis and apoptosis as compared to group I. All these deleterious effects of MSG were greatly ameliorated by TA administration in group IV as compared to group III.

Potential Defence Mechanisms Triggered by Monosodium Glutamate Sub-Chronic Consumption in Two-Year-Old Wistar Rats

“…Also, several studies administered MSG in doses between 2 and 8 g, similar to those that had been given in our research to groups 3 and 4. Increased levels of both enzymes were observed compared to their Control group: 2 g/kg bw/day, for 4 weeks [25,29] and 2.4 g/kg bw/day, for 8 weeks [33]; 4 g/kg bw/day, for 14 days [62]; 5 g/kg bw/day, for 30 days [35]; 8 g/kg corp, for 14 days [63]. Some stud-ies mentioned above used different products, especially natural ones, to counterbalance MSG toxicity.…”

“…The potential toxicity of MSG has been evaluated mainly through preclinical studies. The reported side effects of MSG included (but were not limited to) hepatotoxicity, nephrotoxicity, reproductive system toxicity, cardiotoxicity, neurotoxicity [25][26][27][28][29][30][31]. It has been demonstrated that administration of MSG resulted in histological alterations and impairment in biochemical and metabolic markers such as aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total or direct bilirubin [32,33], cholesterol, triglycerides, creatinine [34] and urea [35].…”

“…4.2.6. Hepatic Histological Modifications Produced by MSG in Rats Reported in the Scientific Literature Scientific studies evaluating MSG toxicity on liver tissue reported several histological modifications following MSG administration, compared to the Control group, as follows: periportal hepatic necrosis associated with mononuclear cell infiltration and single-cell necrosis (2.4 g/kg bw of MSG, for 8 weeks) [33]; moderate atrophied, degeneration in the hepatocytes, marked necrosis, diffuse Kupffer cell proliferation in between some hepatocytes and surrounding the portal area (5 mg/kg bw of MSG, for 4 weeks) [37]; cytoplasmic fatty vacuolation and necrosis of the centrilobular hepatocytes, and fatty vacuolation of the interlobular hepatocytes was observed at a higher dose (5 mg/kg bw/day and 15 mg/kg bw/day of MSG, respectively, for 4 weeks) [26]; vacuolated cytoplasm, highly acidophilic cytoplasm, pyknosis, prominent Kupffer cells and dilated blood sinusoids (2 g/kg bw MSG, for 4 weeks) [25]; hepatocytes cell injury: hydropic degeneration, congested sinusoidal vessels and bi-nucleation (97 mg/kg bw MSG, for 6 weeks) [43]; dilatation of portal vein branches, vacuolar cytoplasmic degeneration of hepatocytes and inflammatory cell infiltrate within the liver lobule (120 mg/kg bw/day of MSG, for 3 months) [44]; marked dilatation of hepatic sinusoids, hepatocyte vacuolation with infiltration of inflammatory cells and small fragmented pyknotic nuclei and apoptotic hepatocytes (4 mg/kg bw/day of MSG, for 7 days) [42].…”

Effect of monosodium glutamate on hepatotoxicity and nephrotoxicity: A mini review

“…Additionally, a recent study found that consuming 2, 4, or 8 g/kg bw of MSG for 14 days enhanced the liver's cytoarchitectural integrity and hepatic enzyme activity alanine transaminase (ALT), aspartate transaminase (AST), and alanine phosphatase (ALP) [29]. In another study reported that 4 weeks of exposure to 2 g/kg bw of MSG significantly damaged the hepatic tissues, causing congestion, dilated blood vessels, and a variety of cellular alterations, including necrosis, apoptosis, polymorphism, and prominent kupffer cells [30]. According to a study, pregnant women and their foetuses who received a 1 g/5 mL/kg bw MSG supplement from day 0 to day 20 of gestation had lower superoxide dismutase (SOD) and glutathione(GSH) activity in addition to higher levels of TNF-and NO in their liver tissue [31].…”

Fenugreek Seed Extract Mitigates MSG-Induced Uterine Dysfunction in Rats through Enhanced Antioxidative Defense Mechanisms

“…Based on numerous scientific research reviews and experiments, MSG has a variety of harmful effects on various organ systems in animal models. (Husarova and Ostatnikov, 2013;Das and Ghosh, 2010;Das and Ghosh, 2011;Okediran et al, 2014;Eweka et al, 2011;Miskowiak and Partyka, 2000;Collison et al, 2012;Alao et al, 2010;Kasozi et al, 2018;Kouzuki et al, 2019;Morita et al, 2021;Lima CB, 2013;Atef and El-moris, 2019;Mohamed et al, 2021).…”