High concentration of MSG alters antioxidant defence system in lobster cockroach Nauphoeta cinerea (Blattodea: Blaberidae)

Abstract

Objective: Monosodium glutamate (MSG) is a food additive that has been shown to be toxic to rodents at high concentrations. The available studies in Drosophila melanogaster suggest that MSG toxicity depends on concentration and gender, thus the safety of MSG as a food enhancer still requires further investigation. We have documented impaired locomotor activity and altered oxidative stress markers in cockroaches co-exposed to methylmercury and monosodium glutamate (MSG). We herein examined the susceptibility of Nauphoeta cinerea to high and low concentrations (4% and 1%) of MSG, while monitoring the activities of acetylcholinesterase (AChE), as well as markers of oxidative stress and antioxidant activity over 30 days. Results: There was no significant alteration in the parameters assessed at 1% MSG while 4% MSG caused an increase in the activity of reactive oxygen and nitrogen species, with a corresponding reduction in the activities of acetylcholinesterase, glutathione-S-transferase and catalase, suggesting the capacity of MSG to alter redox homeostasis in Nauphoeta cinerea.

Dietary monosodium glutamate altered redox status and dopamine metabolism in lobster cockroach ( Nauphoeta cinerea )

“…The peroxidation of biological membranes can alter the optimal conformation of antioxidant enzymes and thereby interfering with its catalytic activity (Carvalho et al., 2015). This also agrees with the previous report of Afolabi and Olagoke (2020) that increased concentration of MSG brought about elevated TBARS level.…”

Potassium bromate cytotoxicity in the Wister rat model of chronic gastric ulcers: Possible reversal by protocatechuic acid

“…The total protein content of gastric tissues was measured using the Biuret method (Gornall et al., 1949) with slight modification of infusing the Biuret reagent with potassium iodide, to prevent the precipitation of Cu 2+ as cuprous oxide as we have earlier reported (Salami et al, 2018). Malonaldehyde (MDA) levels were estimated colorimetrically as an indicator of lipid peroxidation (Adegoke et al., 2017; Buege and Steven, 1978), Catalase activity was measured as a function of the depletion of hydrogen peroxide (Aebi, 1984; Afolabi & Olagoke, 2020), Sulfhydryl content was assayed according to the method of Ellman, 1959 (Ellman, 1959), Nitric oxide was quantified indirectly as total nitrite (NO 2 − ) using Griess reagent (Ignarro et al., 1987; Salami et al., 2016) and the activity of sodium potassium pump in the gastric tissue was measured as phosphate release during incubation with Adenosine triphosphate (Bewaji et al., 1985; Salami, et al, 2018).…”

The investigation of the effects of monosodium glutamate on healthy rats and rats with STZ‐induced diabetes

“…[9] It was also reported in animal studies that excessive MSG causes oxidative stress, cardiac arrhythmia, neurotoxic, hepatotoxic, neoplastic, [10] kidney tissue toxicity, fibrosis, diabetes, behavioral disorders, and muscle wasting. [2,11] Diabetes mellitus (DM) is a chronic metabolic disease that is characterized by high blood sugar, polyuria, polydipsia, and polyphagia, in which insulin secreted from pancreatic β cells is inadequate to maintain blood glucose homeostasis. [12] Carbohydrates, fats, and proteins cannot be adequately utilized because of insulin deficiency or inadequate effect in DM.…”

“…[ 1 ] MSG is a derivative of glutamate, which is not an essential amino acid. [ 2 ] This molecule was described nearly 100 years ago by Kikunae Ikeda as the fifth taste in addition to sweet, sour, salty, and bitter. MSG, which has a unique taste‐umami, was first used widely in Asia and then in western countries.…”

“…[ 9 ] It was also reported in animal studies that excessive MSG causes oxidative stress, cardiac arrhythmia, neurotoxic, hepatotoxic, neoplastic, [ 10 ] kidney tissue toxicity, fibrosis, diabetes, behavioral disorders, and muscle wasting. [ 2,11 ]…”