The Effects of Monosodium Glutamate and Tannic Acid on Adult Rats

Abstract

BackgroundMonosodium glutamate (MSG) is a widely-used flavor enhancer and stabilizer in ready-made or packaged foods. The excessive use of MSG has been shown to increase oxidative stress in different organ systems and causes glucose metabolism disorders, obesity, and coronary diseases.ObjectivesIn this study, the antioxidant activity of tannic acid was investigated experimentally with respect to its protective effects against overdosed MSG-induced oxidative stress in rats. The study took place in Turkey in August 2013.MethodsFour groups (n = 7) of three- to four-month-old Sprague-Dawley female rats were used in this study. The first group was the control, who were administered saline. The second group received tannic acid (50 mg/kg, 3 days) intraperitoneally (i.p.). The third group received MSG (2 g/kg, 7 days) i.p., and the fourth group received both tannic acid (50 mg/kg, 3 days, pretreatment) and MSG (2 g/kg, 7 days) i.p. The animals were euthanized ten days later. Blood was collected for determining the hematological values and blood glucose levels. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were determined in the brain, liver, and kidney homogenates, and in the erythrocyte hemolysate. Histopathological examination of the brain, liver, and kidneys was conducted through hematoxylin-eosin staining.ResultsThe data showed that the tannic acid treatment statistically decreased the MDA levels in the brain tissues of the group administered MSG and tannic acid (P < 0.001) when compared to the corresponding values of the control group. The SOD activities in the blood hemolysates of the MSG and tannic acid group increased when compared to the corresponding values for the MSG group (P < 0.01). Additionally, we found that pretreatment with tannic acid reduced blood glucose levels in comparison to the levels of the MSG group (P = 0.029). The results of our study show that tannic acid pretreatment in adult rats decreased blood glucose levels and oxidative stress.ConclusionsIn the literature, it was observed that short-term MSG exposure does not cause significant histological changes in the kidneys, liver, or brain cortex. These findings should be re-evaluated in additional long-term studies.

Ameliorative Effect of Graviola (Annona muricata) on Mono Sodium Glutamate-Induced Hepatic Injury in Rats: Antioxidant, Apoptotic, Anti-inflammatory, Lipogenesis Markers, and Histopathological Studies

“…The obtained result was in the same line with [76], who attributed this finding to Graviola's ability to restore body fluids and stimulate erythropoietin [77]. Orally administered MSG led to increased oxidative stress markers, such as MDA, ROS, NO, and H 2 O 2 , and decreased SOD, CAT, GST, and GSH that supported this finding by [9,68,[78][79][80][81] as a result of the exhaustion of SOD and accumulation of H 2 O 2 as a result of ROS formation as a result of MSG. Besides [9], this effect is revealed to MSG lipogenesis characters that consume nicotinamide adenine dinucleotide (NAD) + hydrogen (H) (NADH).…”

Natural product of gambier (Uncaria gambier Roxb) extracts to counter against hepatotoxicity effects due to monosodium glutamate induction in male mice

“…Although MSG was given in very large doses (equivalent to 56 mg was converted to mice's dose compared to our study), but there was not show histopatological changes significantly on the organs. [ 17 ] Interestingly, compared to our study, we had found histological changes in the livers by a dose of 5 mg/20 gBW MSG for 28 days.…”

High-fat diet-induced obesity and impairment of brain neurotransmitter pool

“…Monosodium glutamate (MSG), also called sodium glutamate, is used as a flavor enhancer in the food industry. MSG gives a flavor that is impossible to achieve with other food additives [ 48 , 49 , 50 , 51 ]. The obtained positive correlations between brain glutamate as an excitatory neurotransmitter and most of the obesity-related markers in the current study can be supported through the recent work of Hernández Bautista et al [ 52 ], in which an MSG-induced obesity model was associated with inflammation and impaired leptin levels.…”