Monosodium Glutamate Consumption Research Articles

Correction to “Association Between Monosodium Glutamate Consumption with Changes in Gut Microbiota and Related Metabolic Dysbiosis—A Systematic Review“

Correction to “Association Between Monosodium Glutamate Consumption with Changes in Gut Microbiota and Related Metabolic Dysbiosis—A Systematic Review“

Discovery of N-succinyl-L-isoleucine as a novel taste enhancer via multisensory techniques and molecular simulations

As awareness of health implications associated with dietary habits elevates alongside an increase in living standards, the trend toward minimizing sodium chloride and monosodium glutamate consumption has gained prominence. This study explored a novel taste enhancer, N-succinyl-L-isoleucine (N-Suc-Ile), focusing on its synthesis, taste-enhancing effects, and taste-enhancing mechanism. The synthesis of N-Suc-Ile was achieved through enzymatic catalysis employing food-grade enzymes in an aqueous environment, achieving yielding 30.22 %. Quantitative descriptive analysis revealed that the addition of N-Suc-Ile significantly enhanced the intensities of umami (13.11–37.70 %), saltiness (11.11–38.10 %), and kokumi (12.73–49.10 %) in a concentration-dependent manner (0.25–1 mg/L). Furthermore, time-intensity results showed that the durations of both umami and saltiness were prolonged by 46.88 % and 50 %, respectively, with the addition of 1 mg/L N-Suc-Ile. Analysis using sigmoid curves further validated N-Suc-Ile's synergistic effects in enhancing umami and saltiness. Molecular docking and dynamic simulation indicated that N-Suc-Ile bound effectively and stably to taste receptors, enhancing the sensations of umami, saltiness, and kokumi. These findings underscored the potential of N-Suc-Ile as a taste enhancer, suggesting its application could ensure the taste of food products while aligning with health-conscious consumer preferences.

Reevaluating the Legal Status of Monosodium Glutamate Consumption: The Indonesian Ulema Council’s Fatwas and Maqāṣid al-Sharī’ah

This article examines the consistency of the MUI Fatwa regarding Monosodium Glutamate (MSG) from a Maqāṣid al-Sharī’ah standpoint. The legal issue addressed in this research arises from the ongoing debate regarding the consumption of MSG. The Indonesian Ulema Council (MUI) has issued a fatwa declaring that MSG consumption is permissible (halal), provided that it is produced from halal ingredients and is processed, packaged, marketed, distributed, and served in compliance with Islamic law. However, numerous studies have highlighted the adverse effects associated with MSG consumption. This research employs a normative-empirical approach to Islamic law. The primary normative data consists of the MUI fatwa concerning flavoring products, specifically monosodium glutamate, which contains amino acids, as well as various sources discussing Maqāṣid al-Sharī’ah. The primary empirical data is derived from interviews with MUI board members regarding their perspectives on the relevant fatwa. Additionally, non-legal sources, including scientific literature on MSG, are utilized. Through this methodological approach, the research yielded several key findings. Although the MUI has declared MSG consumption as halal, individuals must still adhere to the safety guidelines established by the WHO and the Indonesian Ministry of Health. The MUI further advises against excessive or prolonged consumption of MSG due to its harmful effects on one’s well-being, including the soul, mind, reproductive system, beliefs, and property, all of which Islamic law mandates to be safeguarded. Consequently, the research concludes that the MUI fatwa, along with the explanations provided by its members, aligns closely with the principles of Maqāṣid al-Sharī’ah, as the prevention of harm takes precedence over the pursuit of benefits.

Urinary metabolic profile and its predictive indexes after MSG consumption in rat.

Monosodium glutamate (MSG) is a widely used food additive with conflicting evidence regarding its potential effects on human health, with proposed relevance for obesity and metabolic syndrome (MetS) or chronic kidney disease. As being able to accurately quantify the MSG dietary intake would help clarify the open issues, we constructed a predictive formula to estimate the daily intake of MSG in a rat model based on the urinary metabolic profile. Adult male Wistar rats were divided into groups receiving different daily amounts of MSG in drinking water (0.5, 1.5, and 3.0 g%), no MSG, and MSG withdrawal after 3.0% MSG treatment for 4 weeks. We then analyzed 24-hour urine samples for chemistries and metabolites using 1H NMR spectrometry and observed a strong correlation between urine pH, sodium, bicarbonate, alpha-ketoglutarate, citrate, fumarate, glutamate, methylamine, N-methyl-4-pyridone-3-carboxamide, succinate, and taurine and the daily MSG intake. Following the multiple linear regression analysis a simple formula model based on urinary Na+, citrate, and glutamate was most accurate and could be validated for estimating daily MSG intake. In conclusion, we propose that the daily MSG intake correlates with urinary metabolites in a rat model and that this new tool for monitoring the impact of MSG on health measures.

The Role of Vitamin C on ATPases Activities in Monosodium Glutamate-Induced Oxidative Stress in Rat Striatum and Cerebellum.

Monosodium glutamate (MSG) is a silent excitotoxin used as a flavour enhancer but exerts serious health hazards to consumers. MSG plays a role in neuronal function as the dominant excitatory neurotransmitter. It is transferred into the blood and ultimately increases brain glutamate levels, causing functional disruptions notably via oxidative stress. The study evaluated the toxic effect of high consumption of MSG and the modulatory role of vitamin C on ATPase activities in the striatum and cerebellum of male Wistar rats for five weeks. Rats were grouped into four (A-D): group A was fed with rat's show only; Group B was fed with diet containing 15% MSG; Group C was treated with vitamin C (200mg/kg b.wgt orally in 0.9% saline solution) only for 3weeks; and group D rats were fed with MSG and vitamin C. The findings show that MSG does not affect body and cerebellum weights but increases striatal weight. MSG increases the malondialdehyde (MDA) level and significantly decreases catalase (CAT) and superoxide dismutase (SOD) activities and glutathione (GSH) levels. MSG significantly impaired striatal and cerebellar ATPases activities (Na+/K+-, Ca2+-, Mg2+- and total ATPases). Vitamin C treatment abolishes MSG-induced oxidative stress and improves ATPase activities. The findings show that vitamin C has beneficial effects in improving the functions of membrane-bound ATPases against MSG toxicity in rat's striatum and cerebellum.

A Review of the effects of Monosodium Glutamate on Gut health

Monosodium Glutamate (MSG), constitutes a few of the most commonly encountered additives in processed foodstuffs. Its use has grown throughout the years, and consumers are able to recognise it in a wide variety of processed products, as well as ingredients at any stall or grocery shop. Several investigations have challenged its long-term safety, despite the fact it is usually acknowledged as safe by organisations that oversee food safety. The present review details the impact of MSG on gut health and other complications. Increased MSG consumption, and its potential effects on the gastrointestinal system involving glutamatergic neuronal transmission, inflammatory mediators, and gut microbiota have been reviewed in this article. This narrative review has been performed from January 2023 to June 2023 using the literature obtained from databases like Scopus, PubMed, and other databases of The National Library of Medicine, USA. This review may provide further insights into safety issues related to MSG and its use as a food additive or ingredient.

Investigation of monosodium glutamate content in flavors, seasonings, and sauces from local markets in Turkey.

Monosodium glutamate (MSG) is a flavor-enhancing compound used to elevate the flavor profiles of various foods. This flavor enhancer is the sodium salt of L-glutamic acid and is widely used in foods, such as flavorings, seasonings, sauces, and instant soups. The potential health effects of MSG consumption, particularly the health issues that excessive consumption could lead to, have been the focus of social concerns. It is stated that excessive consumption of MSG can cause cardiovascular diseases, obesity and diabetes, kidney damage, hypertension, anxiety, and memory impairment. The maximum permissible amount of MSG in foods is set at 10 g/kg according to the Turkish Food Codex. The aim of this study is to develop an appropriate method for analyzing the MSG content within the various food samples like flavorings, seasonings, and spices sold in Turkish local markets. The validation parameters of the developed method were examined and it was found that the developed method corresponds to the recommended values. The limit of detection and the limit of quantitation values were calculated as 4.78 ng/mL and 15.93 ng/mL, respectively. Recovery % was determined to be 100.96% in intra-day and 132.22% in inter-day analyses for the precision of the method. The results compared to the values specified in the Turkish Food Codex Food Additives Regulation and samples that purportedly did not contain MSG on their labels were found to contain MSG.

REPRODUCTIVE PERFORMANCE OF MICE ADMINISTERED VARIED CONCENTRATIONS OF MONOSODIUM GLUTAMATE

The impact of varied concentrations of monosodium glutamate (MSG) - a food additive, on the reproductive performance of mice was evaluated using 96 mice -28 males and 68 females, divided into four groups (n = 7 males and 17 females per treatment). Group I received no MSG, group 2 received I mg, group 3 received 2 mg, and group 4 received 4 Ing per gm body weight of 40% aqueous solution of MSG every 48 hrs for six weeks, constituting treatment groups A, B, C, and D. After the sixth week, 15 female mice selected from each treatment were randomly allotted to three male mice of corresponding treatment for multiple mating for 48 hrs. The female mice from each treatment group were monitored through gestation after confirmation of copulation using plug as an index of mating. The conception rate and gestation length increased while the mean live weight of pups decreased with increase in the concentrations of MSG administered. Compared with the weights of pups from the control, the weight of pups from mice in treatment groups B and C decreased by 10.66 and 26%, respectively. The conception rate and the average number of pups decreased significantly (P<0.05) at 2mg of MSG/g BW compared to the control and those administered I mg of MSG/g B W. The gestation length increased significantly (P<0.05) at 21ng of MSG/g BW (treatment C). Dead pups were recorded from mice administered 2mg of MSG/g B W. The result also showed that female mice administered 4mg of MSG/g BW did not give birth. The study revealed that high levels of MSG had adverse effect on the reproductive processes in the laboratory animal. The consumption of MSG, though a flavour enhancer food additive, should be reconsidered taking into account its potential adverse effects on reproductive processes.

Inimical effects of Monosodium Glutamate on various systems

The study of the mechanisms of the effect of various food additives on the human and animal organism is one of the most pressing problems today. physicians, toxicologists, physiologists are aimed at studying the mechanisms of the toxic effect of food additives, as well as studying reactions in response to their ingestion. Monosodium glutamate intentionally added to food in order to keep certain properties or to extend shelf life of the food and to enhance the flavors of it. it is the most common food additive which is used in various countries. Monosodium glutamate is made up of nutritionally indispensable amino acids. This study is aimed to shed light on the available research, which had been carried out on animal and human models regarding possible effects of monosodium glutamate. This review showed that monosodium glutamate was associated with adverse side-effects on various systems of human body like obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects. Available review showed that increased consumption of monosodium glutamate may be associated with harmful health effects.

Association between monosodium glutamate consumption with changes in gut microbiota and related metabolic dysbiosis-A systematic review.

Monosodium glutamate (MSG) is used as a common food additive in some foods. However, based on our search and knowledge, no comprehensive study discussed the effect of MSG on the human gut microbiome. In this study, the effects of MSG on the gut microbiome, liver, and kidney were performed. Data were collected from databases including PubMed, Scopus, Web of Science, and ScienceDirect using the search strategy and keywords. Finally, 14 eligible studies were selected for systematic review. This study provides a new perspective on the effects of MSG on the gut flora, shedding light on the potential relationship between MSG intake and human health.

H Hepatoprotective Activity of Piper crocatum (Ruiz &Pav.) Leaves Against Monosodium Glutamate -Induced Hepatotoxicity in Rats

Monosodium glutamate (MSG) is widely used as additive in food. Excess consumption of MSG was reported to cause oxidative stress on liver resulted increased production of reactive oxygen species (ROS). Without proper treatment, it can induce liver injury and fatal hepatic diseases, including cirrhosis. Red betel (Piper crocatum Ruis and Pav.) is one of Indonesia’s medicinal plants that has been known to exhibit antioxidant activity. The current study evaluated hepatoprotective effect of red betel leaves extract (RBLE) towards liver injury. Animals (n=5 per group) were randomly divided into five groups as follows: Group 1, control (distilled water); group 2, negative control, receive 7 mg/kg bw of MSG; group 3, receive oral 7g/kg b.w of MSG plus 200 mg/kg bw RBLE; group 4, receive oral 7g/kg b.w of MSG plus 400 mg/kg b.w RBLE and group 5, receive oral 7g/kg b.w of MSG plus 600 mg/kg b.w RBLE. The rats were sacrificed on twenty-ninth day of the experiment. Measuring serum levels of aspartate aminotransferase (AST) and alanin aminotransferase (ALT) was done. Histopathological examination of liver was performed by calculated necrosis cell percentage. RBLE treatment (200 mg/kg b.w) decrease alanin aminotransferase and aspartate aminotransferase demonstrated increased compare to negative control. The histological findings revealed RBLE treatment were also able to decrease necrosis cells percentage. The study was able to demonstrate that RBLE treatment could decrease necrotic cell percentage. Low concentration of RBLE (200 mg/kg b.w) exhibit best anti-inflammatory properties and had the lowest ALT enzyme and increased live cell percentage by shifting cell death pathway from necrosis to apoptosis, and these indicating its antioxidant properties. These results could be used as a baseline in the purification of red betel bioactive components to be used for liver injury medication.
 Key words: Antioxidant, hepatoprotective, histopathology, liver enzymes, MSG, red betel.

The Effect of a High Monosodium Glutamate Diet in Inducing Changes in Microbiota Diversity and Kidney Pathology in Hamsters Infected with Opisthorchis viverrini

OBJECTIVE: To investigate the effect of a combination of a high dose of monosodium glutamate (MSG) and chronic Opisthorchis viverrini (O. viverrini) infection on kidney pathology and microbiota changes compared to either factor alone.METHODS: Forty male golden hamsters were divided into four groups (10 hamsters per group): non-infected hamsters fed with standard diet (NC), O. viverrini infected hamsters fed with standard diet (OV), non-infected hamsters fed with high doses of MSG in drinking water (MS), and O. viverrini infected hamsters fed with high doses of MSG in drinking water (OM). After 8 months, fecal samples were collected, DNA extracted and subjected to 16S-rRNA sequencing analysis to determine microbial diversity. Kidneys were also collected for histopathological study.RESULTS: Kidney histopathology showed tubular damages and tubular fibrosis were significantly prominent in the OM group, which showed higher pathology changes than in the OV group or MS groups. Next generation sequencing indicated that the levels of Firmicutes to Bacteroides ratio decreased in the OV group (0.28), MS group (0.43) and OM group (0.43) respectively when compared to control group (0.52). In genus levels, Methanobrevibacter, Ruminococcus_1, Escherichia Shigella, Bacteroides, Akkermansia and Oligella were abundance in the OM group.CONCLUSION: The changing of gut microbiota distribution and kidney pathology changes were more severe in the cases of O. viverrini infection together with MSG consumption. This study provides a first step towards focusing on diet and parasitic infections.

Hematological changes, oxidative stress assessment, and dysregulation of aquaporin-3 channel, prolactin, and oxytocin receptors in kidneys of lactating Wistar rats treated with monosodium glutamate.

High consumption of locally produced delicacies could expose nursing mothers to high monosodium glutamate (MSG) levels, frequently used as a necessary condiment in low-income countries. Thus, this study evaluated some novel preliminary changes in renal hormonal receptors, the aquaporin-3 channel, oxidative stress markers, and hematological indices induced by monosodium glutamate in lactating rats. Post-parturition, twenty-four (24) lactating Wistar rats were divided into four (4) groups of six rats each (n = 6). Oral administration of distilled water and MSG started three (3) days postpartum as follows: group 1: distilled water (1ml/kg BW), group 2: MSG (925mg/kg BW), group 3: MSG (1850mg/kg BW), and group 4: MSG (3700mg/kg BW). At the end of the experiment, which lasted fourteen (14) days, animals were sacrificed and samples of blood and tissues were obtained for biochemical analysis. MSG administration significantly (p < 0.05) increased ROS and MDA, with a significant (p < 0.05) decrease in kidney antioxidants. Serum creatinine, total, conjugated, and unconjugated bilirubin significantly (p < 0.05) increased with MSG administration. The prolactin receptor was significantly reduced (p < 0.05), while the oxytocin receptor and aquaporin-3 channel were significantly (p < 0.05) increased in the MSG-administered groups. There were significant (p < 0.05) changes in the hematological indices of the MSG-administered animals. Thus, the findings of this study suggest that high MSG consumption causes hematological alterations and may alter renal function via increased ROS production and dysregulation of the AQP-3 channel, prolactin, and oxytocin receptors in the kidneys of lactating Wistar rats.

Preliminary monosodium glutamate-induced changes in mammary gland receptors and gene expression, water channel, oxidative stress, and some lactogenic biomarkers in lactating rats

BackgroundChanges induced by monosodium glutamate (MSG) can negatively impact milk production and secretion, among other adverse effects. This study aimed to investigate the effects of MSG consumption on receptor gene expression and quantification of hormones and receptors, as well as oxidative stress biomarkers and other lactogenic parameters in lactating animals. Twenty-four female Wistar rats, nine weeks of age, were randomly assigned to four groups, each containing six rats, at parturition. The rats in groups II, III, and IV were given varying doses of monosodium glutamate (MSG); while, group I was given distilled water and served as the control. The experimental period lasted two (2) weeks.ResultsThe groups administered with MSG showed a significant decrease in mammary PRLR gene expression (p < 0.05), as well as a marked reduction (p < 0.05) in mammary PRLR, OXT receptor, AQP-3, brain antioxidant enzymes (SOD, GPx, and CAT), and pituitary SOD compared to the control group (p < 0.05). Furthermore, there was a significant increase (p < 0.05) in reactive oxygen species levels in the serum and mammary gland homogenates, erythrocyte osmotic fragility, and elevated (p < 0.05) brain and pituitary MDA levels in the MSG-administered groups compared to the control group. Daily milk yields were significantly decreased (p < 0.05) in the MSG-administered groups between days 10 and 14 of lactation.ConclusionThe findings of this study suggest that prolonged consumption of MSG could interfere with lactation-associated functions via increased ROS production, reduced antioxidants, decreased AQP-3, mammary prolactin and oxytocin receptors, and prolactin receptor mRNA in lactating Wistar rats.Graphical

Hepatoprotective Effects of Dayak Onion (Eleutherine palmifolia) Extract on SGOT and SGPT Enzyme Activity in Mice (Mus musculus) Following Chronic Dose Administration of Monosodium Glutamate

This study aimed to explore the liver-protecting properties of Dayak onion (Eleutherine palmifolia) extract in mice exposed to chronic doses of monosodium glutamate (MSG). The research involved 25 male mice, each about 11 weeks old and weighing around 20 grams. These mice were divided into five groups for different treatments. The control group (C-) received only a harmless substance, while the positive control group (C+) was given MSG at 4 mg per gram of body weight. The three treatment groups (T1, T2, and T3) received the same amount of MSG along with varying doses of Dayak onion extract: 30, 60, and 120 mg per kilogram of body weight, respectively. The experiment ran for 52 days. On the 53rd day, the researchers humanely euthanized the mice and collected blood samples directly from their hearts. This blood was used to measure the activity of two important liver enzymes: SGOT and SGPT. The results showed a significant difference in enzyme activity between the MSG-only group and the control group. Interestingly, in the groups treated with Dayak onion extract, the enzyme activity decreased as the extract dose increased. This suggests that the extract was counteracting the harmful effects of MSG on the liver. The researchers concluded that Dayak onion extract demonstrated protective effects on the liver in mice exposed to chronic doses of MSG. The most effective dose of Dayak onion extract was found to be 120 mg per kilogram of body weight. This study provides valuable insights into the potential of Dayak onion extract as a natural remedy for liver damage caused by MSG consumption, opening avenues for further research in this area.

In silico and in vivo analysis of the relationship between ADHD and social isolation in pups rat model: Implication of redox mechanisms, and the neuroprotective impact of Punicalagin

Attention deficit hyperactivity disorder (ADHD) has high incidence rate among children which may be due to excessive monosodium glutamate (MSG) consumption and social isolation (SI). AimWe aimed to explore the relationships between MSG, SI, and ADHD development and to evaluate the neuroprotective potential of Punicalagin (PUN). MethodsEighty male rat pups randomly distributed into eight groups. Group I is the control, and Group II is socially engaged rats treated with PUN. Groups III to VII were exposed to ADHD-inducing factors: Group III to SI, Group IV to MSG, and Group V to both SI and MSG. Furthermore, Groups VI to VIII were the same Groups III to V but additionally received PUN treatment. Key findingsExposure to MSG and/or SI led to pronounced behavioral anomalies, histological changes and indicative of ADHD-like symptoms in rat pups which is accompanied by inhibition of the nuclear factor erythroid 2-related factor 2 (Nrf2)/Heme-oxygenase 1 (HO-1)/Glutathione (GSH) pathway, decline of the brain-derived neurotrophic factor (BDNF) expression and activation of the Toll-like receptor 4 (TLR4)/Nuclear factor kappa B (NF-kB)/NLR Family Pyrin Domain Containing 3 (NLRP3) pathway. This resulted in elevated inflammatory biomarker levels, neuronal apoptosis, and disrupted neurotransmitter equilibrium. Meanwhile, pretreatment with PUN protected against all the previous alterations. SignificanceWe established compelling associations between MSG consumption, SI, and ADHD progression. Moreover, we proved that PUN is a promising neuroprotective agent against all risk factors of ADHD.

Sungkai Leaf Extract (Peronema canescens Jack) Reduces MDA Levels and Increases IL-10 Levels in MSG-Induced Wistar Rats

The addition of Monosodium Glutamate (MSG) to ready-to-eat food can change eating habits, coupled with a lack of activity which can have an impact on health. MSG as a trigger for increased reactive oxygen species (ROS), causing systemic damage, the impact of excessive MSG consumption can be reduced by modifying the diet to contain high sources of antioxidants. Sungkai leaf extract can be an alternative as a natural antioxidant. Sungkai leaf extract antioxidants are expected to neutralize ROS thereby repairing cell damage. Objective: This study aims to determine how giving sungkai leaf extract affects MDA and IL-10 levels in MSG-induced mice. Method: Experimental research with a Randomized Post test only control group design. The total sample was 24 male Wistar rats divided into 4 groups. KN healthy mice, K(-) were given 1g MSG/rat, P1 was given 1g MSG/rat and 28mg sungkai leaf extract/rat, P2 was given 1g MSG/rat and 56mg sungkai leaf extract/rat. Results: The average results showed a decrease in MDA levels and an increase in IL-10 levels after treatment for 21 days, the One way Anova test followed by Post hoc LSD showed that each treatment group was significantly different from the control group where the MDA level in group P2 was 0, 07mg/ml ± 0.01 experienced a significant decrease compared to the KN group 0.07mg/ml ± 0.01 while IL-10 levels experienced a significant increase in the P1 group 130.10pg/ml ± 13.29 when compared to the KN group 60.43pg/ml ±17.40. Conclusion: Sungkai leaf extract (Penonema Canescens Jack) was able to reduce MDA levels at a dose of 56 mg/mouse in mice injected with 1gr MSG/rat and experienced a significant increase in IL-10 levels with a dose of 28 mg sungkai leaf extract/rat injected with 1gr MSG/rat.

Exploring diet-induced promoter hypomethylation and PDK4 overexpression: implications for type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by limited metabolic flexibility in the body. Such limitation implicates the pyruvate dehydrogenase kinase 4 (PDK4) gene Poor nutrition, frequently observed among Southeast Asians usually involves excessive intakes of carbohydrates and monosodium glutamate (MSG), that have been frequently linked to an increased risk of T2DM. The 14-week study aimed to assess the effects of high-carbohydrate (HC), high-MSG (HMSG), and a combination of high-carbohydrate and high-MSG (HCHMSG) diets on the development of T2DM using male mice. To assess the effects, the male mice were divided into four groups: control (C), HC, HMSG, and HCHMSG for 14weeks. After 14weeks, both the HC and HCHMSG groups showed signs of T2DM (168.83 ± 32.33; 156.42 ± 32.46). The blood samples from the HMSG, HC, and HCHMSG groups (57.67 ± 2.882; 49.22 ± 7.36; 48.9 ± 6.43) as well as skeletal muscle samples from the HMSG, HC, and HCHMSG groups (57.78 ± 8.54; 42.13 ± 7.25; 37.57 ± 10.42) exhibited a gradual hypomethylation. The HC groups particularly displayed significant PDK4 gene expression in skeletal muscle. A progressive overexpression of the PDK4 gene was observed as well in the HMSG, HCHMSG, and HC groups (2.03 ± 3.097; 3.21 ± 2.94; 5.86 ± 2.54). These findings suggest that T2DM can be induced by high-carbohydrate and high-MSG diets. However, the sole consumption of high MSG did not lead to the development of T2DM. Further research should focus on conducting long-term studies to fully comprehend the impact of a high MSG diet on individuals with pre-existing T2DM.

Protective Effects of Melatonin on Hepatic Injury Due to Chronic Monosodium Glutamate Consumption in Adult Female Rats

In the present study, it was aimed to investigate the effects of Monosodium Glutamate (MSG) consumption on rat liver and the possible antioxidant and anti-inflammatory effects of melatoninin protecting against MSG-induced hepatic damage. Thirty two adult female rats were randomly divided into 4 groups. For 30 days, MSG (2g/kg/day) or melatonin (4mg/kg/day) was given daily in drinking water or both melatonin and MSG were given simultaneously at the same doses, while normal drinking water was given to the control group. Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST) levels were investigated in the serum of rats decapitated at the end of the experiment. In liver sections, Hematoxylin-Eosin (H-E), Sirius red, Periodic Acid Schiff (PAS) staining for histopathological damage examination, Nuclear Factor-kappa B (NF-κB), smooth muscle a-actin [alpha-Smooth Muscle Actin (a-SMA)], NADPH Oxidase (NOX-2), Transforming Growth Factor (TGF)-β1, SMAD2, SMAD7 immunohistochemistry were applied. At the end of the experiment, % body weight change in MSG group rats was high, and serum ALT and AST levels were increased compared to control group, while these levels weredecreased with melatonin administration. In addition, vacuolization in hepatocytes, dilatation in sinusoids, increase in Kupffer cells andinflammatory cell foci were detected in the MSG group. When melatonin wasadded to MSG, decreased hepatocyte glycogen content and SMAD7 immunoreactivity with increased a-SMA were observed along with improvements in NF-kB, NOX-2, TGF-β1, SMAD2 immunoreactivity. Our findings suggest that melatonin, with its antioxidant and anti-inflammatory effects, may be a potential agent to prevent liver damage that can be caused by MSG in the diet.

Monosodium Glutamate Intake and Risk Assessment in China Nationwide, and a Comparative Analysis Worldwide.

The sixth Total Diet Study (TDS) of China included a countrywide study to assess the health effects of MSG (monosodium glutamate). MSG detection, consumption analysis, and risk assessment were conducted on 168 samples from seven food categories of the most typical Chinese daily diet. The highest value of MSG in the daily diet of the Chinese population was 8.63 g/kg. An MSG intake of 17.63 mg/kg bw/d for the general population of China was obtained from content measurements combined with food consumption, while the data from the apparent consumption survey alone gave 40.20 mg/kg bw/d. The apparent consumption did not consider the loss of MSG during food cooking, resulting in an overestimate. To offer a global perspective, MSG content, food category contributions, and ingestion levels across nations were summarized and thoroughly investigated. A realistic, logical, and precise risk assessment protocol for MSG daily intake was developed in this article.