Monosodium glutamate induced testicular toxicity and the possible ameliorative role of vitamin E or selenium in male rats

Effects of dietary supplementation of grape seed extract in comparison with excessive level of vitamin E on growth performance and antioxidant function of broilers

The present study was carried out to evaluate the effects of dietary vitamin E (VE) or grape seed extract (GSE) on the growth performance and antioxidant function of broilers. Two hundred sixteen broiler chicks were randomly assigned to 3 diets: diet supplemented with oxidized rice bran oil (CN group), CN group with 25 mg/kg VE or 100 mg/kg GSE. Dietary VE or GSE improved the growth performance, reverted the disturbed levels of liver antioxidant enzymes, and reduced liver damage of broilers fed oxidized rice bran oil. The mRNA data showed that supplementation of VE or GSE enhanced the antioxidant capacity of the broiler liver through activation of the Keap1-Nrf2/ARE signaling pathway. The results suggested that VE and GSE can increase weight gain, improve the oxidative status, and alleviate liver injury in broiler chicken fed oxidized rice bran oil.

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 (1 ml/kg BW), group 2: MSG (925 mg/kg BW), group 3: MSG (1850 mg/kg BW), and group 4: MSG (3700 mg/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.

Mitochondrial Differentiation during Spermatogenesis: Lessons from Drosophila melanogaster

Numerous diseases can arise as a consequence of mitochondrial malfunction. Hence, there is a significant focus on studying the role of mitochondria in cancer, ageing, neurodegenerative diseases, and the field of developmental biology. Mitochondria could exist as discrete organelles in the cell; however, they have the ability to fuse, resulting in the formation of interconnected reticular structures. The dynamic changes between these forms correlate with mitochondrial function and mitochondrial health, and consequently, there is a significant scientific interest in uncovering the specific molecular constituents that govern these transitions. Moreover, the specialized mitochondria display a wide array of variable morphologies in their cristae formations. These inner mitochondrial structures are closely associated with the specific functions performed by the mitochondria. In multiple cases, the presence of mitochondrial dysfunction has been linked to male sterility, as it has been observed to cause a range of abnormal spermatogenesis and sperm phenotypes in different species. This review aims to elucidate the dynamic alterations and functions of mitochondria in germ cell development during the spermatogenesis of Drosophila melanogaster.

Disruptive consequences of monosodium glutamate on male reproductive function: A review

Monosodium glutamate (MSG) is one of the most extensively used flavour enhancers worldwide. Although it is widely regarded as a safe food additive with no recommended daily dosage, its over-consumption has been associated with notably pathophysiological events in various tissues and organs of the body. Previous studies have reported of the neuro- cardio- and hepato- toxic effects of its excessive exposure. Moreover, the food additive instigates metabolic dysfunction. It has been established that MSG damages male reproductive accessory organs like prostate glands and epididymis. In addition, it impairs serum enzymatic activities and serum levels of testosterone, gonadotropin-releasing hormone, luteinizing hormone and cholesterol. Reduced sperm count, sperm motility, sperm morphology, and sperm viability, imbalances in male reproductive hormones, alongside alteration in the histoarchitecture of the testes and other male reproductive tissues have also been connected with excessive exposure to MSG. Literature reports affirm the link between the over-consumption of MSG and reproductive organ weight and male sexual behaviour. This review article addresses the multi-systemic effects of exposure to MSG and the possible mechanism of action of the compound with a focus on the negative implications of the food additive on male reproductive functions and the possible role of natural antioxidants in male reproductive functions. carefully selected keywords were used during the literature search to gather credible and up-to-date information about the subject matter.

A Study on the Awareness and Perceptions Regarding Monosodium Glutamate and its Potential Health Effects Amongst the Urban Population of Saudi Arabia

Introduction Monosodium glutamate (MSG), a common global food additive in processed foods, influences flavors and textures due to its chemical complexity and nutritional intricacy. Despite an annual production of 1.9 million tons and historical safety concerns, the multifaceted impact on health, ranging from metabolic disorders to neurological and cardiovascular implications, necessitates ongoing research for informed consumption and balanced dietary practices. Materials and methods This cross-sectional study investigates MSG-associated intricacies among Saudi Arabia's urban population. The research included questionnaire development, translation, and cultural adaptation, and was validated by nutrition experts. A sample size of 420 was calculated for a 95% confidence level. Data collection occurred from September 13 to October 31, 2023, and ethical considerations were ensured. Statistical analysis, including chi-square tests, regression analysis, and SPSS, explored intricacy relationships. Results The MSG intricacy study in Saudi Arabia's urban population, involving 420 respondents, showed statistically significant correlations (P < 0.05) in demographics. The key findings indicate an awareness of the impact of MSG on health, its associations with various conditions, and strong support for its exclusion from foods. Region, gender, age, and social status correlations highlighted diverse perspectives. The Western province showed the highest response rate at 42.61%, prompting regional awareness questions. Gender dynamics showed that 90.47% of the respondents were females, emphasizing potential gender-specific concerns. Concentration among ages 20-30 (61.9%) underscored generational factors. While commendable baseline awareness was noted, 73.09% of the participants believing MSG is harmful prompts further investigation. Emotional responses, including happiness (25.95%) and frustration (18.33%), highlight the complexity of the individuals' experiences, emphasizing the need for tailored communication strategies. Conclusion The MSG intricacy study in Saudi Arabia's urban population reveals insights into knowledge, attitudes, and behaviors, emphasizing the need for nuanced interventions considering regional and emotional differences. The findings underscore health concerns, supporting regulations, and knowledge impact on behavior. This survey serves as a valuable tool for informed public discourse and decision-making in the unique socio-cultural context of urban Saudi Arabia.

The interplay between monosodium glutamate (MSG) consumption and metabolic disorders

Monosodium glutamate (MSG) is one of the most popular food additives in the world and is often ingested with commercially processed foods. It can be described as a sodium salt of glutamic acid with the IUPAC name - Sodium 2-aminopentanedioate and is ionized by water to produce free sodium ions and glutamic acid. MSG use has significantly increased over the past 30 years, its global demand stands huge at over three million metric tons which is worth over $4.5 billion. Asia was responsible for more than three quarter of world MSG consumption with the country China also leading in global consumption as well as production and export to other countries. Prior to year 2020, global demand for MSG increased by almost four percent each year with the highest significant increase in demand for MSG predicted to rise in Thailand, Indonesia, Vietnam and China, followed by Brazil and Nigeria. However, several researches featured in this review has identified MSG consumption as a major contributor to the development and progression of some metabolic disorders such as obesity, which is a risk factor for other metabolic syndromes like hypertension, diabetes mellitus and cancer initiation. The mechanism by which MSG induce obesity involves induction of hypothalamic lesion, hyperlipidemia, oxidative stress, leptin resistance and increased expression of peroxisome proliferator-activated receptors (PPARs) Gamma and Alpha. Similarly for induction of diabetes mellitus, MSG consumption resulted in decreased pancreatic beta cell mass, increased oxidative stress and metabolic rates, reduced glucose and insulin transport to adipose tissue and skeletal muscles, insulin insensitivity, reduced insulin receptors and induced severe hyperinsulinemia. Dietary salt, an active component of MSG is also found to be a major risk factor for high blood pressure (which may lead to hypertension). MSG is used to enhance the taste of tobacco, causing smokers to consume the product in excess and thereby increasing the risk of cancer development. Depending on the amount consumed, MSG has both positive and negative effects. Despite the controversy surrounding MSG's safety and its probable contribution to risk of development and progression of metabolic disorders, its global consumption is still very high. Therefore, this article will sensitize the public on the need for cautious use of MSG in foods and also aid regulatory agencies to further review the daily MSG consumption limit based on metabolic toxicities observed at the varied dosages reported in this review.

Monosodium Glutamate Effect on The Expression of ɑ7nACHR and ɑ4nACHR Subunits in The Testicular Tissue

BACKGROUND

Monosodium glutamate (MSG) is a popular food flavor enhancer, and a glutamate subset that induces different toxicities such as hepatotoxicity, neurotoxicity, reproductive toxicity, and nephrotoxicity. This study was conducted to assess the effects of MSG on the α7 and α4 nicotinic acetylcholine receptor (nACHR) protein subunits expression of adult rat testis and the safety role of vitamin C.

MATERIALS AND METHODS

For this experimental research, 24 rats were haphazardly grouped into four equal groups (n=6) and orally gavaged for 30 days as follows: control group (distilled water gavage), MSG group (3 g/kg/b.w/ day), vitamin C group (150 mg/kg/b.w/day), and MSG+vitamin C group (3 g/kg/b.w/day+150 mg/kg/b.w/day, respectively) that rats of all groups on the 30th day were anesthetized, and the left testes were used for of α4 and α7 nACHR protein subunit evaluation by immunohistochemistry (IHC). Statistical computations were performed using Graph Pad Prism software.

RESULTS

The present study revealed a significant reduction in the expression and optical density (OD) of α7 nACHR and α4 nACHR in the seminiferous tubules and intertubular connective tissue in the MSG group compared to the control group. In the MSG+vitamin C group, the expression and OD of α7 nACHR and α4 nACHR increased in the seminiferous tubules and intertubular connective tissue but this improvement was not significant compared to the MSG group.

CONCLUSION

MSG decreased the expression level of nACHR protein subunits, α7 and α4, in the seminiferous tubules and interstitial testicular tissue. Vitamin C in the MSG+vitamin C group could not significantly improve the expression of α7 and α4 nACHR subunits in testicular tissue. Probably, MSG toxicity can be compensated with higher doses of vitamin C.

Apocynin Ameliorates Monosodium Glutamate Induced Testis Damage by Impaired Blood-Testis Barrier and Oxidative Stress Parameters

BACKGROUND

the aim of this study was to investigate the effects of apocynin (APO) on hormone levels, the blood-testis barrier, and oxidative biomarkers in monosodium glutamate (MSG) induced testicular degeneration.

METHODS

Sprague Dawley male rats (150-200 g; n = 32) were randomly distributed into four groups: control, APO, MSG, and MSG + APO. MSG and MSG + APO groups were administered MSG (120 mg/kg) for 28 days. Moreover, the APO and MSG + APO groups received APO (25 mg/kg) during the last five days of the experiment. All administrations were via oral gavage. Finally, biochemical analyses were performed based on the determination of testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD), as well as light and transmission electron microscopic examinations, assessment of sperm parameters, ZO-1, occludin, NOX-2, and TUNEL immunohistochemistry were evaluated.

RESULTS

MSG increased both the oxidative stress level and apoptosis, decreased cell proliferation, and caused degeneration in testis morphology including in the blood-testis barrier. Administration of apocynin reversed all the deteriorated morphological and biochemical parameters in the MSG + APO group.

CONCLUSIONS

apocynin is considered to prevent testicular degeneration by maintaining the integrity of the blood-testis barrier with balanced hormone and oxidant/antioxidant levels.

Investigation of the Effects of Monosodium Glutamate on the Embryonic Development of the Eye in Chickens

MSG is the most ubiquitous food additive in the food industry. The aim of this report was to investigate the effects of in ovo MSG administration on embryonic chicken eye development using histological and histometric methods. A total of 410 fertilized eggs obtained from Babcock Brown laying hens (Gallus gallus domesticus) were used and divided into 5 groups: I (untreated control), II (vehicle control), III (0.12 mg/g egg MSG), IV (0.6 mg/g egg MSG), and V (1.2 mg/g egg MSG), and injections were performed via the egg yolk. At incubation day 15, 18, and 21, 6 embryos from each group were sacrificed by decapitation and pieces of eye tissue were obtained. In all MSG groups, it was determined that both corneal epithelium thickness and total corneal thickness decreased at incubation time points 15, 18, and 21 days compared with the controls (p < 0.05). The total retinal thickness, thickness of the outer nuclear layer (ONL), inner nuclear layer (INL), ganglion cell layer (GL), and nerve fibre layers (NFL), as well as the number of ganglion cells decreased significantly at incubation days 15, 18, and 21 (p < 0.05), and degenerative changes such as vacuolar degeneration and retinal pigment epithelial detachment were also observed. In conclusion, MSG in ovo administration can affect the cornea and distinct layers of retinal cells.

Testicular Effect of Selenium Nanoparticles on Monosodium Glutamate Induced Alteration in Male Albino Rats

<b>Background and Objective:</b> The flavor enhancer Monosodium Glutamate (MSG) is mostly utilized in Asian and West African cuisines, especially in West African and Asian dishes. However, due to its availability, largely without labeling, in many food products, unintentional overuse of this food additive may occur. The objective of this study was to find out how selenium nanoparticles affected the toxicity of MSG in male albino rats' testicles. <b>Materials and Methods:</b> As 35 Wistar male rats partitioned into 5 groups: G1: Control rats, G2: Received Se-NPs at 0.4 mg kg¹ b.wt., orally, G3: Injected with MSG at a daily dose of 4 g kg¹ b.wt., intraperitoneally (IP), G4: Ingested a daily oral dose of Se-NPs for 7 successive days and on the 7th day, received the first dose of MSG IP 4 g kg¹ b.wt., then received both treatments till the end of the study and G5: Administered a daily oral dose of 4 g kg¹ MSG, followed by Se-NPs at a daily dose of 0.4 mg kg¹ b.wt., the experiment continued for 28 days. Serum testosterone hormone, Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), the levels of serum lipid peroxidation (MDA), reduced Glutathione (GSH), Glutathione Peroxidase (GSH-Px), superoxide dismutase (SOD) and Lactate Dehydrogenase (LDH) were estimated and samples from testis were separated for histological analysis. <b>Results:</b> The MSG treatment induced a significant decline in the values of serum testosterone, FSH, LH, GSH, GSH-Px and SOD. It also increased the values of serum MDA and LDH and spermatic arrest. While, the administration of Se-NPs orally before MSG treatment resulted in a decline in the values of serum MDA and LDH, an elevation in the values of serum GSH, GSH-PX and SOD, testosterone, FSH, LH and reappearance of sperm. <b>Conclusion:</b> The use of Se-NPs as a protector exhibited more improvement in values of estimated hormones and oxidative stress markers than using it as a therapy.

The protective effect of L-carnitine on testosterone synthesis pathway, and spermatogenesis in monosodium glutamate-induced rats

Background

Monosodium glutamate (MSG) is a food ingredient that is increasingly used commercially. MSG leads to oxidative stress, consequently suppressing steroid hormone production that causes defects in male reproductive system. This study aimed to evaluate the effect of L-carnitine as an antioxidant on testicular damage in MSG-induced male rats.

Methods

Sixty adult male Spargue-Dawley rats were randomly divided into six groups of ten as follows: control (water), sham (normal saline), L-carnitine (200 mg/kg b.w), MSG (3 g/kg b.w), MSG + L-carnitine 100 (3 g/kg b.w of MSG and 100 mg/kg b.w of L-carnitine), and MSG + L-carnitine 200 (3 g/kg b.w of MSG and 200 mg/kg b.w of L-carnitine). The treatment was administered by oral gavage for six months. Serum levels of Malondialdehyde (MDA), Total Anti-oxidant Capacity (TAC), LH, FSH, testosterone, and mRNA expressions of Star, Cyp11a1, and Hsd17b3 genes, and histological and stereological changes were assessed.

Results

L-carnitine led to a significant decrease in the level of MDA and a significant rise in the serum levels of TAC, LH, FSH, and mRNA expression of Star and Cyp11a1 compared to the MSG group (p < 0.05). Furthermore, stereological results indicated a significant increment in the number of sexual lineage cells, the total volume of the testis, length, diameter, and volume of seminiferous tubules, the height of the germinal epithelium, sperm count, and sperm motility (p < 0.05) in MSG + L-carnitine 200 compare to MSG group.

Conclusion

The study’s findings demonstrated that L-carnitine due to its anti-oxidant properties, ameliorated the reproductive abnormalities in the male rats exposed to MSG.

MONOSODYUM GLUTAMAT, LEZZET ARTTIRICI MI, ÖLDÜREN LEZZET Mİ?

Monosodium glutamat (MSG) 1800’lü yıllardan beri lezzet artırıcı katkı maddesi olarak, işlenmiş ve paketlenmiş tuzlu veya tatlı gıdalarda kullanılmaktadır. Yapılan birçok çalışma MSG kullanımının çok sayıda yapısal ve fonksiyonel bozukluklara yol açabileceğini ortaya çıkarmıştır. Son yıllarda MSG kullanımının çok artması gıda güvenliği konusunda endişelerinde artmasına neden olmuştur.

Histopathological and biochemical effect of quercetin on monosodium glutamate supplementation-induced testicular toxicity

Background

Despite the wide usage of monosodium glutamate (MSG) as a flavor enhancer in many types of food, it has been reported as a toxic agent to humans and experimental animals. It also adversely influences male fertility. Several research studies attributed detrimental effects of MSG on reproductive organs to oxidative stress. The current study investigated the effects of MSG on testis and the potential role of quercetin in attenuating them.

Results

MSG-treated rats showed a considerable elevation in lipid peroxidation level and reduction in glutathione concentration, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities in the homogenate of testis tissues. Treatment with quercetin in combination with MSG provided significant protection. When QU was used, the toxic side effects were significantly reduced, with a considerable reduction in lipid peroxidation and an increase in SOD and GPx activities, and glutathione concentration.

Conclusions

Quercetin may be used in combination with MSG to improve the histopathological, ultrastructure, oxidative stress, and biochemical parameters of testicular toxicity induced by MSG due to its antioxidant effects.

Graphical abstract

Glutamate - A multifaceted molecule: Endogenous neurotransmitter, controversial food additive, design compound for anti-cancer drugs. A critical appraisal

One of the most widely used flavour enhancers in the food industry is monosodium glutamate (MSG). MSG consumption has been on an upward trend, worrying in terms of potential toxic effects. This review is focused on the long-term toxicity of MSG and the experimental evidence that supports it. The article's primary purpose was to survey recently published data regarding the consumption of MSG within safe limits. The administered doses in animal models are very varied and have given rise to controversy. Also, the paper comprises pathways to lower MSG toxicity and highlight other underexploited biological effects, as anti-cancer potential. The administration of MSG, combined with various compounds, has been shown benefit against toxic effects. Several recent studies have identified a possible mechanism that recommends MSG and some derivatives as potential anti-cancer agents. New anti-cancer compounds based on the glutamic acid structure must be studied and further exploited. International regulations require harmonization of safe doses of MSG based on current scientific studies. Replacing MSG with other umami flavour enhancers may be a safer alternative for human health in the future. The biological consequences of MSG consumption or therapeutical administration have not been fully deciphered yet.

Assessment of Reproductive Toxicity of Hydroethanolic Root Extracts of Caesalpinia benthamiana, Sphenocentrum jollyanum, and Paullinia pinnata

Purpose

Male sexual dysfunction negatively affects an individual's quality of life and thus its of prime public concern, hence the need to boost reproductive abilities in such individuals. This study assessed the effect of hydroethanolic root extracts of Caesalpinia benthamiana (CBRE), Sphenocentrum jollyanum (SJRE), and Paullinia pinnata (PPRE), commonly used as aphrodisiacs in Ghana, using male Sprague-Dawley rats.

Methods

Plasma testosterone, follicle-stimulating hormone, and luteinizing hormone were assayed in grouped rats treated orally with 1 mL/kg normal saline, 50 mg/kg monosodium glutamate (MSG), and 100, 300, or 1000 mg/kg CBRE, SJRE, and PPRE, respectively, for 60 days. Epididymis and testis weights were determined. Semen was assessed on spermatozoa count, motility, and morphology. Malonyladehyde formation in lipid-peroxidation assay and histological examinations were performed to assess pathological changes in testes. Testicular testosterone was also assayed.

Results

While MSG, CBRE, SJRE, and PPRE treatments did not result in significant reduction (p>0.05) in plasma testosterone, there was significant reduction (p≤0.05 -0.0001) in plasma luteinizing hormone, and follicle-stimulating hormone. The combined mean wet weights of epididymides and testes of all treated groups did not vary significantly (p>0.05) from the control. There was significant reduction (p≤0.0001) in sperm motility and count, with significant morphological changes (p≤0.05-0.001), ie, bent necks, tails, and midpieces, and multiple anomalies in the spermatozoa in extract and MSG-treated groups. There was also significant (p≤0.0001) reduction in testicular testosterone among all treatment groups.

Conclusion

Hydroethanolic CBRE, SJRE, and PPRE were found to have detrimental effects on reproductive function with prolonged usage and thus may not be safe to use in healthy males who intend to reproduce.

Effects of monosodium glutamate on testicular structural and functional alterations induced by quinine therapy in rat: An experimental study

BACKGROUND

Quinine (QU) as an anti-malarial drug induces alterations in testicular tissue. Toxic effects of monosodium glutamate (MSG) on the male reproductive system have been recognized.

OBJECTIVE

To investigate the impact of MSG administration on the intensity of gonadotoxicity of QU.

MATERIALS AND METHODS

Sixty eight-wk old Wistar rats weighing 180-200 gr were divided into six groups (n = 10/each): the first group as a control; the second and third groups received low and high doses of MSG (2 & 4 gr/kg i.p.), respectively, for 28 days; the fourth group received QU for seven days (25 mg/kg); and in the fifth and sixth groups, QU was gavaged following the MSG administration (MSG + QU) from day 22 to day 28. Serum testosterone and malondialdehyde (MDA) levels were measured. Testes samples were prepared for tissue MDA levels, histomorphometry, and immunohistochemistry of p53. Sperm analysis was performed on cauda epididymis.

RESULTS

Serum and tissue MDA levels were increased in treated groups compared to the control group. This increment was higher in the MSG + QU groups. The testosterone levels were reduced significantly (p < 0.0001) in all treated groups. In addition, histomorphometric indices and tubular epithelium population were reduced significantly (p < 0.0001) in QU, MSG + QU, and consequently in high-dose MSG, QU, MSG + QU groups. All spermatogenic indices were reduced in the treated groups, particularly in the MSG + QU groups. Sperm motility and viability indices were reduced significantly (p = 0.003) in the MSG + QU groups. Finally, the overexpression of p53 was observed in the MSG + QU groups.

CONCLUSION

The administration of MSG before and during QU therapy may intensify testicular tissue alterations.

Antiapoptotic and antioxidant capacity of phytochemicals from Roselle (Hibiscus sabdariffa) and their potential effects on monosodium glutamate-induced testicular damage in rat

Monosodium glutamate (MSG), common flavor enhancer and feed additive, causes male reproductive dysfunction. However, Roselle tea, popular Hibiscus sabdariffa (HS) beverage, has a controversial effectiveness on male fertility. Therefore, the current study aimed to investigate either the adverse effect of aqueous HS extract (HSE) on the testicle or its potential ameliorative role including some stress markers, biochemical and immunohistochemical expressions in rats subjected to MSG. Here, the animals were divided into four groups that were given distilled water, HSE, MSG, and HSE + MSG respectively via gavage. After 6 weeks from the beginning of experiment, blood samples were collected for hormonal analysis. Additionally, testicular specimens were excised and processed for oxidative/antioxidant parameters determination, histological examination, and immunohistochemical evaluation of Bax and PCNA positive spermatogenic cells. Preliminary phytochemical analyses as well as antioxidant capacity of the HSE were tested. Our results revealed a strong inhibitory activity of the HSE phytochemical constituents against DPPH radical. MSG group revealed a significant decrease of testosterone, LH, FSH, and antioxidant parameters with elevated MDA compared with control and HSE groups. Additionally, an alteration of the testicular histo-architecture was observed among MSG group along with increased Bax and decreased PCNA positive cells. Meanwhile, the HSE showed a potent protective effect against testicular damage as well as oxidative stress induced by MSG. On the whole, our findings provide evidence that HSE can ameliorate MSG-induced testicular toxicity via induction of cell proliferation along with reduction of oxidative stress and cellular apoptosis in adult rat that attributed to the antioxidant and antiapoptotic effects of its phytochemical constituents.

Monosodium glutamate induces memory and hepatic dysfunctions in mice: ameliorative role of Jobelyn® through the augmentation of cellular antioxidant defense machineries

This study investigated the effect of high doses of monosodium glutamate (MSG), a known food additive on hepatic, memory and locomotor functions in mice, and the ameliorative potentials of Jobelyn^® (JB), a unique dietary supplement. Twenty four  male Swiss mice  divided into 4 groups (n = 6) were given MSG (2, 4 and 8 g/kg) or normal saline (10 mL/kg) orally for 14 days. In the intervention study, another set of 30 male Swiss mice distributed into 5 groups (n = 6) received normal saline, MSG (8 g/kg) alone or in combination with JB (5, 10 and 20 mg/kg) orally, for 14 days. Memory and locomotor functions as well as brain oxido-nitrergic stress biomarkers were then assessed in both studies. The hepatic oxido-nitrergic stress biomarkers, liver enzymes functions and histomorphology of the liver were also assessed. MSG (2, 4 and 8 g/kg) produced memory dysfunction, hyperlocomotion, increased malondialdehyde and nitrite levels accompanied by decreased antioxidant status in the brain and hepatic tissues. MSG-treated mice had increased hepatic enzyme activities (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) and distorted cyto-architectural integrity of the liver. These findings further suggest that MSG compromised hepatic functioning, which might also contribute to its neurotoxicity. However, JB (5, 10 and 20 mg/kg, p.o) attenuated the memory deficit, hyperlocomotion, increased oxido-nitrergic stress responses in the brain and hepatic tissues induced by MSG (8 g/kg, p.o). JB also normalized hepatic enzymes activities and histomorphological changes in MSG-treated mice. Taken together, JB mitigated MSG-induced toxicity through mechanisms relating to enhancement of cellular antioxidant-machineries and normalization of hepatic enzymatic functions.

L-Glutamic acid monosodium salt reduces the harmful effect of lithium on the development of Xenopus laevis embryos

Many xenobiotics in the environment affect the human body in various ways. Among those xenobiotics, lithium chloride (Li, LiCl) and monosodium glutamate (L-glutamic acid monosodium salt, MSG) compounds affect the crucial processes of stem cell differentiation, cell proliferation, developmental gene expression, and overall development in animals. In this study, we aimed to examine the developmental effects of exposure to flavor enhancer MSG and LiCI medicament on Xenopus embryos using the frog embryo teratogenesis assay of Xenopus test. To this purpose, Xenopus laevis embryos were exposed to four different concentrations of MSG (120, 500, 750, 1000 mg/dL) and Li (0.02 g/L) alone and in combinations for a period of 96 h, and then normal, abnormal, and death ratios were determined in all exposure groups. Besides, length values of all groups and membrane potentials of fertilized and non-fertilized oocyte groups treated with 120- and 500-mg/dL MSG doses and 0.02-g/L LiCI dose were measured. Treatment with ADI (acceptable daily intake) dose of MSG alone did not lead to a substantial effect on the development of Xenopus laevis embryos. But, exposure to daily doses exceeding the ADI level (500, 750, 1000 mg/dL) caused significant harmful effects. Besides, Li-involving treatments caused dramatic deleterious effects on embryo development. MSG attenuated harmful effects of Li in MSG+Li combined treatments. Membrane potentials of non-fertilized oocytes and fertilized eggs were significantly changed in all groups that their membrane potentials were measured. Extrapolating these results into humans require similarly designed studies conducted on human embryos.

Zinc oxide nanoparticles with green tea extract complex in the pancreas of rats against monosodium glutamate toxicity

OBJECTIVES

Nanotechnology is an exciting field for investigators. Green zinc oxide nanoparticles (ZnO NPs) with Camellia sinensis extract complex are proved to be used in the treatment of the toxicity of monosodium glutamate (MSG) in the liver, kidney, and testis of rats. Therefore, the synthesized complex of green nanoparticles using green tea extract (GTE) was tested against the toxicity of MSG on the pancreas.

METHODS

The glucose and insulin levels were estimated as well as some biochemical parameters for evaluating the antioxidant status of the pancreas tissue. The histopathological change of the pancreas also has been determined.

RESULTS

It indicates the biomedical capability of ZnO NPs/GTE to act as potent antidiabetic through decreasing blood glucose and increasing serum insulin also, inhibition of lipid peroxidation and enhancement of the antioxidant parameters.

CONCLUSIONS

The ZnO NPs/GTE enhanced the pancreatic cell and Langerhans islets as well lowered the sugar levels and stimulated insulin.

Ameliorative Role of Green Tea and Zinc Oxide Nanoparticles Complex Against Monosodium Glutamate-Induced Testicular Toxicity in Male Rats

BACKGROUND AND OBJECTIVE

This study was designed to estimate the long-term effects of zinc oxide nanoparticles/green tea (ZnONPs/GTE) complex against monosodium glutamate (MSG). The antioxidant/oxidative status, testosterone levels, DNA damage, and histopathological changes of testis were evaluated.

METHODS

The rats were divided into eight groups that were treated as follows: saline, the lower dosage of MSG (6.0 mg/kg), the higher dosage of MSG (17.5 mg/Kg), GTE, ZnONPs, ZnONPs/GTE and the last two groups were treated with the lower dosage of MSG or the higher dosage of MSG with ZnONPs/GTE complex. The data showed minimal toxicity in testicular tissue after the administration of ZnONPs.

RESULTS

The MSG treatment in the adult male rats reduced testosterone levels and disrupted testicular histology, which revealed dose-dependence of MSG. Also, ZnONPs induced testicular dysfunction through the interference of antioxidant/oxidant balance and suppression of testosterone levels as well as induction of cellular damage of testis. The combination of ZnONPs with GTE complex significantly protects against MSG or ZnONPs toxicity by decreasing the DNA damage, oxidative stress, and enhancement of antioxidant as well as histological structure of testis.

CONCLUSION

We could recommend using ZnONPs/GTE complex to reduce the toxicity of ZnONPs and MSG on the testis at the cellular and oxidative stress levels.

Testicular protective and antioxidant effects of selenium nanoparticles on Monosodium glutamate-induced testicular structure alterations in male mice

Background

Selenium has a protective antioxidant effect on several tissues. Monosodium glutamate (MSG), MSG has been known as flavor enhancer that influences reversely on male reproductive systems and having a number of side effects, including reproductive toxicity.

Objectives

The current study aims to evaluate the possible ameliorative functions of selenium nanoparticles (SeNPs) on MSG-induced reproductive toxicity.

Materials and methods

In total, 42 male mice included in this study were divided into six groups: control, MSG (LD), MSG (HD), SeNPs, MSG (LD) plus SeNPs and finally MSG (HD) plus SeNPs. Testosterone hormone, tumor necrosis factor-alpha (TNF-α), as well as the antioxidant biomarkers: superoxide dismutase [SOD], glutathione peroxidase [GPx], catalase [CAT] and marker of lipid peroxidation [MDA], were examined. Histological and comet assay variations in the testicular tissues as markers of testicular damage after the MSG administration in two doses (MSG-LD and MSG-HD) either alone or combined with SeNPs.MSG in two doses (LD and HD) genotoxic effects were also evaluated and the ameliorative role of SeNPs on the testicular tissues were recorded.

Results

Results proved that the administration of SeNPs diminished the effect of MSG (LD and HD)-that induced decrease in testosterone hormone levels and elevated oxidative stress markers markedly. SeNPs had a potent antioxidant effect and elevated the antioxidant enzymes significantly and decreased lipid peroxidation markers as compared with MSG either (LD and HD) groups.

Conclusion

It is clear from the data that SeNPs inhibit testicular injury and improve the antioxidant state in male mice.

In vitro genotoxicity assessment of monopotassium glutamate and magnesium diglutamate

Food additives are approved chemicals used for various purposes in foods; to provide nutritional safety, increase flavor, extend shelf life, reduce nutrient losses etc. In this study, the in vitro genotoxic effects of flavor enhancers, Monopotassium glutamate (MPG) and Magnesium diglutamate (MDG) were investigated in human peripheral blood lymphocytes by using chromosome aberrations (CAs), sister chromatid exchanges (SCEs), cytokinesis-block micronucleus cytome (CBMN-Cyt), and comet assays. Four concentrations of MPG (125, 250, 500, and 1000 μg/mL) and MDG (93.75, 187.5, 375, and 750 μg/mL) were used. Both food additives significantly reduced mitotic index and increased the frequency of CAs at high concentrations. MPG and MDG (except 93.75 μg/mL) significantly increased SCEs/Cell in concentration-dependent manner. In the CBMN-Cyt test, both MPG and MDG increased the formation of micronucleus, nuclear buds, and nucleoplasmic bridges compared to control in a concentration-dependent manner. However, these increases were statistically significant at higher concentrations. MPG (at 500 and 1000 μg/mL) and MDG (except 93.75 μg/mL) significantly increased DNA damages observed by comet assay. It is concluded from these results that MPG and MDG have clastogenic, mutagenic, aneugenic, and cytotoxic effects, particularly at high concentrations in human lymphocytes in vitro.

Monosodium Glutamate (MSG)-Induced Male Reproductive Dysfunction: A Mini Review

Reproductive dysfunction is often characterized by malfunction of the reproductive tissues, which may lead to disruption of the synergistic rhythm that should bring about a progression of sexual events and the conception of new life. This may therefore result in the sexual dysfunction and infertility that can be seen in couples having prolonged biological difficulty in reproducing their offspring after having unrestricted sexual intercourse for at least twelve months. Several factors have been implicated in the cause and progression of reproductive dysfunction, including poor nutrition, drug side effects, disease states, and toxicant ingestion. A well-known food additive that has been found to be potent at initiating reproductive anomalies in males is monosodium glutamate (MSG). This regular flavor enhancer is widely used as a taste enhancer in several diets. The different mechanisms by which it may induce reproductive dysfunctions include spermatogenic alteration resulting in a low sperm count, high sperm abnormality, reduced live sperm and decreased sperm pH, oxidative damage (increased lipid peroxidation and reduced antioxidant enzyme activities), histological alteration (blood hemorrhage, distorted germ and Sertoli cells), as well as gonadotropin imbalance (reduced testosterone, luteinizing hormone, and follicle-stimulating hormone concentrations). Therefore, this review discusses various established mechanisms through which MSG may induce reproductive dysfunction and the treatment strategies to ameliorate its toxic effects.

Testicular protective effects of ellagic acid on monosodium glutamate-induced testicular structural alterations in male rats

Ellagic acid (EA) has significant protective and antioxidant effects on several tissues. Monosodium glutamate (MG) is known as a flavor promoter that reversibly influences the male reproductive system. This study aims to assess the ameliorative effect of EA on oxidative stress and testicular damage induced by MG. In total, 48 male rats were included in this study and separated into six groups: control, EA (20 mg/kg), MG (low dose) (17.5 mg/kg), MG (high dose) (60 mg/kg), MG (low dose) combined with EA, and MG (high dose) combined with EA. Testicular antioxidant biomarkers [superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GRx), catalase (CAT), myeloperoxidase (MPO), and xanthine oxidase (XO)] were examined. Testes were examined and scored for histological variation as an indicator of testicular damage following administration of MG alone or in combination with EA. Serum testosterone, inhibin B, 8-hydroxydeoxyguanosine (as a marker of DNA damage), and transmission electron microscope sections of the testis were evaluated, and a comet assay was performed. Results showed that administration of EA combined with MG significantly elevated the levels of enzymatic antioxidants and decreased lipid peroxidation compared with MG treatment alone. EA elevated testosterone hormone levels and thus enhanced male reproductive capacity. It is clear from the data that EA inhibits histological and ultrastructure testicular damage and improves the redox state in male rats.

The Interaction of Zinc Oxide/Green Tea Extract Complex Nanoparticles and its Effect on Monosodium Glutamate Toxicity in Liver of Rats

BACKGROUND

Zinc oxide nanoparticles (ZnO NPs) are increasingly utilized in both industrial and medical applications. Therefore, the study was aimed to investigate the effect of green nanoparticle complex (green tea extract/zinc oxide nanoparticles complex, GTE/ZnO NPs) on oxidative stress induced by monosodium glutamate (MSG) on the liver of rats.

METHODS

Wistar male rats (n=64) weighing between 200-250 g were divided randomly into eight groups: control group was given physiological saline (1 mg/kg), two groups were treated with two different doses of MSG (MSG-LD, MSG-HD; 6 and 17.5 mg/Kg, respectively), GTE was given 1 mg/mL, 5th group was treated with ZnO NPs and 6th group was treated with GTE/ZnO NPs complex while, 7th and 8th groups were treated with MSG-LD + GTE/ZnO NPs complex and MSG-HD + GTE/ZnO NPs complex, respectively. All substances were given orally for 30 consecutive days. At the end of the study, the liver was homogenized for measurement of the oxidative stress status and anti-inflammatory biomarkers as well as histological and transmission alternations.

RESULTS

Results showed that the antioxidant enzymes activity and glutathione level were significantly decreased in MSG groups than control in a dose-dependent manner. Conversely, the malondialdehyde and inflammatory cytokines levels were significantly increased in MSG groups than the control group. The liver indicated no evidence of alteration in oxidative status, anti-inflammatory and morphological parameters in GTE, ZnO NPs and GTE/ZnO NPs complex groups.

CONCLUSION

In conclusion, MSG at both doses caused oxidative stress and inflammation on liver after 28 days of exposure that supported histological analysis and transmission view of hepatic parenchyma. GTE/ZnO NPs act as partial hepato-protective against MSG.

Evaluation of the effects of the green nanoparticles zinc oxide on monosodium glutamate-induced toxicity in the brain of rats

Background

Monosodium glutamate (MSG) is used extensively as a food additive in the diets of many countries around the world.

Aim of the study

Our aim was to determine the effects of green zinc oxide nanoparticles on MSG-induced oxidative damage, neurotransmitter changes, and histopathological alternation in the cerebral cortexes of rats.

Methods

MSG was administered orally at two doses of 6 and 17.5 mg/kg body weight. The higher dose was associated with a significant decline in the activities of superoxide dismutase, catalase, and glutathione peroxidase, as well as the levels of brain-derived neurotrophic factor (BDNF) and glutathione (GSH) in the cerebral cortex of rats.

Results

The administration of zinc oxide nanoparticles/green tea extract (ZnO NPs/GTE) to 17.5 mg/kg MSG-treated rats was associated with significant improvements in all parameters previously shown to be altered by MSG. The higher dose of MSG induced significant histopathological variation in brain tissue. Co-treatment of rats with ZnO NPs/GTE and MSG-HD inhibited the reduction of neurotransmitters and acetylcholinesterase by MSG.

Conclusions

ZnO NPs/GTE have the potential to protect against oxidative stress and neuronal necrosis induced by MSG-HD. ZnO NPs/GTE conferred a greater benefit than the control treatment or ZnO NPs or GTE administered separately.

Evaluation of the Effect of Nanoparticles Zinc Oxide/Camellia sinensis Complex on the Kidney of Rats Treated with Monosodium Glutamate: Antioxidant and Histological Approaches

Background:

Zinc oxide nanoparticles (ZnO NPs) are robustly used biomedicine. Moreover, no study has been conducted to explore the consequence of green synthesis of ZnO NPs with Camellia sinensis (green tea extract, GTE) on kidneys of rats treated with monosodium glutamate (MSG).

Methods:

Therefore, the objective of the research was designed to explore the possible defensive effect of GTE/ZnO NPs against MSG-induced renal stress investigated at redox and histopathological points.

Results:

The levels of urea and creatinine increased as the effect of a high dose of MSG, in addition, the myeloperoxidase and xanthine oxidase activates were elevated significantly with the high dose of MSG. The levels of non-enzymatic antioxidants (uric acid, glutathione, and thiol) were decreased sharply in MSG-treated rats as compared to the normal group.

Conclusion:

The data displayed that GTE/ZnO NPs reduced the effects of MSG significantly by reduction of the level peroxidation and enhancement intracellular antioxidant. These biochemical findings were supported by histopathology evaluation, which showed minor morphological changes in the kidneys of rats.

Effects of monosodium glutamate on apoptosis of germ cells in testicular tissue of adult rat: An experimental study

Background

Monosodium glutamate (MSG) is used as a flavoring and food seasoning. Some studies have reported the oxidative effects of using this substance on various tissues.

Objective

This study has investigated the effects of MSG and the protective effect of vitamin C (vit C) on apoptosis of testicular germ cells and biochemical factors.

Materials and Methods

In this experimental study, 24 adult male Wistar rats were randomly divided into four groups: control (received distilled water), vit C group (150 mg/kg), experimental group 1 (MSG 3 gr/kg), experimental group 2 (MSG 3 gr/kg + vit C 150 mg/kg). The rats were gavaged for 30 days, and then were sacrificed, the right testis was isolated for biochemical examinations for the glutathione, malondialdehyde, and left testis used in histological experiments. Tunnel staining was used to determine the number of apoptotic cells.

Results

The results showed that apoptotic cells in the MSG group had a significant increase compared to the control group (P = 0.001), but the number of these cells in the MSG co-administered with vit C and vit C groups were significantly lower than the MSG group. Germinal epithelial thickness also decreased in MSG group compared to the control group.

Conclusion

MSG can lead to increase apoptotic changes in the germinal epithelial of the testicle, and vit C as an antioxidant can modify the pathological and biochemical changes induced by MSG.

Monosodium glutamate daily oral supplementation: study of its effects on male reproductive system on rat model

Monosodium glutamate (MSG) is widely used in food preparation industry and has been consumed regularly. Previous studies had reported on effects of MSG when given at extremely high dosages, the results are not applicable to human equivalent intake. Therefore, the present study aimed to evaluate the effect of MSG on sperm quality and changes in reproductive organs of adult male rats when taken at average human daily intake (ADI). Twenty-four adult male rats were randomly assigned into three groups; NC (Normal control), MSG60 and MSG120 where MSG was given orally at 60 mg/kg and 120 mg/kg to each respective group. All treatments were conducted for 28 consecutive days. MSG at estimated ADI of 120 mg/kg body weight resulted in a significant drop in sperm quality (p < 0.05) when compared to both control and MSG60 groups. A significant decrease in the weight of reproductive organs was also apparent (p < 0.05). Moreover, oxidative status evaluation showed that treatment of MSG induces oxidative stress in the testis, more severely at a dose of 120 mg/kg body weight. These findings are supported by alterations in the observed histology of reproductive organs. This study shows that an intake dose of 120 mg/kg body weight MSG could cause significant damage to the reproductive system. Abbreviations: MSG: Monosodium glutamate; ADI: average daily intake; PUFA: polyunsaturated fatty acid; FSH: follicle stimulating hormone; LH: luteinizing hormone; TCA: tricarbocylic acid; PF: prostatic fluid.

Mutagenicity comparison of nine bioselenocompounds in three Salmonella typhimurium strains

Selenium (Se) is an essential element in animals but becomes severely toxic when the amount ingested exceeds the adequate intake level. It is known that the toxicological effects of Se are highly dependent on its chemical form. In this study, we evaluated the mutagenicity of nine naturally occurring Se compounds or the so-called bioselenocompounds, including selenite, selenate, selenocyanate, selenomethionine, selenocystine, Se-methylselenocysteine, selenohomolanthionine, N-acetylgalactosamine-type selenosugar, and trimethylselenonium ion, by using the Ames test. Salmonella typhimurium TA98, TA100, and TA1535 were used for the mutagenicity evaluation in the presence or absence of S9 mix, a metabolic activator. Only selenate showed weak mutagenicity even in the absence of S9 mix. None of the bioselenocompounds except selenate exhibited mutagenicity in all the strains tested in the presence or absence of S9 mix. Selenomethionine and selenocystine reduced the number of colonies in all the strains although no other selenoamino acids exerted the same effect. These results indicate that selenate directly or indirectly injures genome. Among the bioselenocompounds tested, selenomethionine and selenocystine show antibacterial activity, but the mechanism is unclear.

The Ameliorating Effect of Sodium Selenite on the Histological Changes and Expression of Caspase-3 in the Testis of Monosodium Glutamate-Treated Rats: Light and Electron Microscopic Study

Monosodium glutamate (MSG) is a commonly used flavor enhancer that may contribute to male infertility. Sodium selenite is inorganic chemical form of selenium (Se). Se is best known as an antioxidant. This study was designed to investigate the possible ameliorating role of sodium selenite against MSG-induced testicular toxicity and histological changes. Forty male albino rats were allocated into four groups. Control group received distilled water, SE group received sodium selenite (0.25 mg/kg/day) dissolved in distilled water orally, MSG group received MSG (6 mg/g/day) dissolved in distilled water orally, and MSG + SE group received both MSG and sodium selenite for 45 days. Testicular samples were prepared for biochemical, light, and electron microscopic studies. Immunohistochemical staining for caspase-3 was done. MSG group demonstrated a significant increase in malondialdehyde level, marked damage of seminiferous tubules with a significant reduction in diameter and height of the lining epithelium. Spermatogenic cells showed disorganization, dark nuclei, reduction in number, and maturation arrest. Vacuolations of interstitial tissue and Leydig cells were also observed. Percent area of fibrosis and caspase-3 immunoexpression was significantly increased. Ultrastructurally, irregular tubular basement membrane and damaged germ cells were found. The spermatogenic, Sertoli, and Leydig cells showed irregular shrunken nuclei, cytoplasmic vacuolations, and swollen mitochondria. MSG + SE group showed much better histological and ultrastructural picture and improvement of the measured biochemical and morphometric parameters. Percent area of caspase-3 immunoexpression was significantly decreased. In conclusion, sodium selenite ameliorated the testicular damaging effect of MSG through reduction of oxidative stress and apoptosis.

Effect of selenium on testicular damage induced by varicocele in adult male Wistar rats

PROJECT

Varicocele is an abnormal tortuosity and distension of the veins of the pampiniform plexus in the spermatic cord. It is the most common surgically correctable cause of male infertility. Several studies have revealed the effects of increased oxidative stress on serum, semen, and testicular tissues in patients with varicocele or in animal models. The aim of this study was to investigate the effects of sodium selenite on testicular damage induced by experimental left varicocele in male Wistar rats.

PROCEDURE

In the present study, the effects of oral administration of sodium selenite (at doses of 0.05, 0.1, 0.2, and 0.4mg/kg bw) were assessed in normal and varicocelized rats.

RESULTS

The varicocelized control rats showed decrease in sperm quality parameters, decreased activity of testes CAT, GPX and SOD, increased levels of MDA, and damage in testicular architecture. Administration of sodium selenite significantly reduced these changes to nearly normal levels, but did not change these parameters in normal rats. Histopathological studies further confirmed the protective effects of sodium selenite on varicocele-induced testicular damage in rats. Administrations of sodium selenite did not change these parameters in normal rats.

CONCLUSIONS

Taken together, the results of this study suggest that sodium selenite treatment may have beneficial effect on the testes of varicocelized rats.

Monosodium glutamate-induced oxidative kidney damage and possible mechanisms: a mini-review

Animal studies suggest that chronic monosodium glutamate (MSG) intake induces kidney damage by oxidative stress. However, the underlying mechanisms are still unclear, despite the growing evidence and consensus that α-ketoglutarate dehydrogenase, glutamate receptors and cystine-glutamate antiporter play an important role in up-regulation of oxidative stress in MSG-induced renal toxicity. This review summaries evidence from studies into MSG-induced renal oxidative damage, possible mechanisms and their importance from a toxicological viewpoint.