Histopathological and immunohistochemical studies on the influence of orally administration monosodium glutamate, a food additive dependent on time in vivo
The Journal of Basic and Applied Zoology volume 83, Article number: 59 (2022)
Monosodium glutamate is a widely used flavor enhancer/food additive in meat, fish, milk and cheese or vegetable origins. Our present study aimed to assess the effect of utilization monosodium glutamate on the cardiac, splenic, hepatic and renal organs in mice. Thirty animals were divided into three groups: control group; glutamate 10 treated groups and glutamate 15 treated group. The experimental period was two successive weeks.
Oral administrations of monosodium glutamate for 10 days induced moderate histopathological changes in cardiac, splenic, hepatic and renal tissues and also resulted in significant increase of the nuclear factor-kB expression depend on time of administration as compared to the control group, while treatment with monosodium glutamate for 14 days resulted in severe histopathological changes as well as highly significant increase of the nuclear factor-kB expression as compared to the control group.
It could be concluded that oral administration of monosodium glutamate induced histopathological alterations, and cytotoxicity in cardiac, splenic, hepatic and renal tissues dependent on time.
Monosodium glutamate, the salt of glutamic acid which is a common food additive, is widely used as a preservative or palatability (Ali et al., 2014). It consists of the sodium salt of glutamic acid (Eweka, 2007), of glutamic acid (78%), sodium and water (22%) (Samuels, 1999) and is metabolized in the liver (Garattiini, 2000). In nature, glutamate (Glutamic acid) is considered as one of the most common amino acids and is the main component of many proteins and peptides of most tissues (Aisha, 2014; Wu, 2010). In the human body, glutamate has an essential role in metabolism (Aisha, 2014), cell signaling, anti-oxidative responses and immunity (Wu, 2010). The main sources of glutamic acid are all meats, poultry, fish, eggs, dairy products, tomato and some protein-rich plant foods, hydrolyzed protein such as yeast extract and many fermented or aged foods, including soy sauce and fermented bean paste (Burrin & Stoll, 2009). Many prepared foods use glutamate in the form of monosodium glutamate as an additive (Berkes & Wossner, 2003). Monosodium glutamate is recorded on food labels as a “Flavoring” and has the ability to ameliorate the meals palatability and induce positive appetite and gain of weight. It is usually used in many food products such as noodles, flavored potato chips, many food snacks, soups, frozen foods and stuffed chicken (Eweka, 2007). In addition, it is mostly used in the home, fast foods, restaurant and food industries.
It is known that consumption of dietary monosodium glutamate resulted in different unwanted effects such as sweating, muscle pain, fatigue, headache, neuropathy, ventricular arrhythmia, abdominal discomfort, skin reactions and asthma in human (Geha et al., 2000). Similarly, it also induces pathologies in the liver tissues (Eweka et al., 2011), testis of rat (Igwebuike et al., 2011) and ovaries of female mice (Das & Ghosh, 2011; Mustafa et al., 2015) and female rats (Bojanic et al., 2009). In addition to, monosodium glutamate, induced histopathological alteration on the retina of rabbit as recorded by Ali et al. (2012).
The U.S. Food and Drug Administration considers MSG safe, while the European Union’s Food Safety Authority determines an intake of 30 mg/kg body weight per day as safe (Peng et al., 2018). However, administration of monosodium glutamate at a low concentration of 5 mg/kg of body weight for 28 days caused hepatotoxic (Egbuonu et al., 2009) and renal toxicity at dose of 4 mg/kg of body weight (Ragab, 2018) as evidences by histological, immunohistochemical and ultrastructure studies. In addition, Ebaid and Tag (2012) also found that rat administrated with 4 mg/kg of monosodium glutamate for 14 days showed severe spleen damage. Likewise, Hassan et al. (2014) reported toxicity of monosodium glutamate when administration to rats at a dose 3 g/kg body weight (1/5 LD50) daily for 8 weeks in thymic and splenic tissues after prolonged consumption. Diab and Hamza (2016) also recorded the toxic influences of monosodium glutamate in the function of liver tissue in rats. They reported that administration of monosodium glutamate at a dose of 60 mg/kg for 4 weeks resulted in the elevation of hepatic enzymes and lipid profile such as cholesterol, triglycerides. Likewise, Kumbhare et al. (2015) stated that monosodium glutamate at the dose 3 mg/kg body weight induced conspicuous pathological lesions in the liver tissue when it was administrated orally for 45 successive days. Neurotoxicity (hazards to the structure of cerebellar cortex, Purkinje cell layer with necrotic widely spaced cells) of monosodium glutamate was also evaluated by Aidaros et al. (2019). Therefore, the aim of our paper was designed to study the influence of monosodium glutamate administration on cardiac, splenic, hepatic, and renal tissues of male Swiss albino mice using histopathological and immunohistochemical studies.
Thirty animals were divided into three groups: The first group served as control and were treated orally with distilled water (1 ml/kg.bw), the second group (Glutamate 10 treated group) were orally administrated with monosodium glutamate at dose 4 mg/kg body weight for 10 days according to Ragab (2018), and the third group (Glutamate 14 treated group) were orally administrated with monosodium glutamate at dose 4 mg/kg body weight for 14 days according to Ragab (2018). At the end of the experimental, the animals were euthanized after 24 h of the last dose by decapitation by administering an intraperitoneal injection of sodium pentobarbital (50 mg /kg) and dissection and cardiac, splenic, hepatic and renal tissues were freshly collected and immediately fixed into 10% formalin for histopathological and immunohistochemistry examination.
Monosodium glutamate was obtained from Shanghai Bio Life Science & Technology Co., Ltd. (China) while others chemicals were obtained from Sigma-Aldrich (St. Louis, MO, USA).
Animals and ethics
Animals were obtained from the animal house of the National Organization for Drug Control and Research (NODCAR) in Giza, Egypt. In this study, thirty male Swiss albino mice aged 9–12 weeks and weighing 25–30 g were used. Animals were provided with a standard marketable diet pellets and water that Ad-labium reserved in cages of plastic for 7 days to be acclimatized to laboratory condition before treatment. All animals were grouped and housed according to the guidelines of the institutional animal's ethics committee of NODCAR. All male Swiss albino mice were grouped and housed according to the guidelines of the institutional animal’s ethics committee of NODCAR. All experimental procedures were conducted in accordance with the ethical standards and were approved by the Institutional Animal Care and Use Committee (IACUC) at National Organization for Drug Control and Research (NODCAR), (approval no. NODCAR/III/41/2019).
After 48 h of fixation in 10% formalin, the cardiac, splenic, hepatic and renal were washed, dehydrated in ascending grades of alcohol, cleared in xylene and embedded in paraffin wax. Five-micron-thick paraffin sections were prepared, mounted on clean slides and stained with Ehrlich's hematoxylin–eosin for histological study (Bancroft & Gamble, 2002).
NF-κB (nuclear factor-kB) immunostaining was carried out on the heart, spleen, liver and kidney tissues with PBS containing 113 0.05 M EDTA followed by 4% paraformaldehyde. 5-μm sections were incubated with blocking reagent, primary antibody anti-NF-κB (17) in the presence of 10% rabbit serum overnight at 4 °C, followed by biotin-conjugated goat anti-rabbit Ig, avidin-linked HRP complex and 3,3'-diaminobenzidine as substrate. For quantification measurement, slides were counterstained with hematoxylin, followed by dehydration, examination under a light microscope. The intensity of brown color indicator for cell immunopositivity was observed (Soria-Valles et al., 2015). Ten readings were obtained in each specimen using Leica Qwin 500 image analyzer the computer system (England) in the faculty of medicine, Cairo University.
The experimental data were analyzed using analysis of variance (ANOVA) with GraphPad Prism (version5.00 for Windows), GraphPad Software (CA, USA). P < 0.01 is considered to be significant. All calculated data are expressed as mean ± standard deviation (SD).
Histopathological examination of cardiac tissues
Microscopically examinations of cardiac tissues from control mice revealed normal arrangement of longitudinal cardiac myocytes with a centrally arranged nucleus. On the other hand, histopathological examination of cardiac tissues in male Swiss albino mice treated with monosodium glutamate for 10 and 14 days, respectively, revealed variable degrees of alterations in response to the time of the treatment and compared to control as follows: Cardiac sections from mice treated with monosodium glutamate for 10 days showed moderate pathological lesions, areas of cardiomyocyte display homogenous cytoplasm and pyknotic nuclei as well as marked congested dilated blood vessels and mild inflammatory cells aggregations in interstitial tissues and perivascular. Other areas revealed degenerated splitting fragmentation cardiac muscular fibers with widening interstitial tissues compared with control treated group. Animals treated with monosodium glutamate for 14 days showed severe degenerated changes. Severe degenerated atrophied fiber with pyknotic nuclei, edema, marked congested dilated blood vessels with ulcerated wall; widening interstitial tissues together with inflammatory cells aggregations in interstitial tissues and perivascular were seen (Fig. 1).
Histopathological examination of splenic tissue
Microscopic examination of splenic sections from normal mice revealed normal splenic architecture with normal appearance of white pulp and red pulp. White pulp is formed of a large number of lymphocytes surrounding the central arteries and red pulp is formed of reticular cells, red blood cells, lymphocytes, macrophage, and some plasma cells. On contrast, splenic sections from animal orally administrated with monosodium glutamate showed variable degrees of alterations dependent on time. Ten-day treatment revealed ill-defined spleen architecture, degenerated white pulp and red pulp together with lost and loosely cells accompanied with scattered giant cells compared to the control group. While severe degenerative changes in white pulp and red pulp as ill-defined lymphoid follicle with large necrotic foci by darkly stained cells accompanied with edema, diffused degenerated lymphoid cells were shown in splenic sections from mice treated with monosodium glutamate for 14 days (Fig. 2).
Histopathological examination of hepatic tissue
Examination of H & E hepatic sections from control mice showed normal appearing of hepatocyte that radiated from central vein and separated by sinusoids. However, liver sections from mice administrated monosodium glutamate for 10 days showed moderate pathological changes as moderate dilated, central vein, and vacuolar degenerative hepatocyte together with mild to moderate inflammatory cells aggregation in perivascular, in sinusoids compared to control group, while treatment with monosodium glutamate for 14 days showed severe degenerative changes compared to control group. Prominent areas of marked vacuolar degenerative hepatocyte with pyknotic nuclei, severe dilated, congested portal veins andmoderate dilated bile ducts together with dense inflammatory cells aggregation in hepatic tissues and in perivascular (Fig. 3).
Histopathological examination of renal tissue
Histopathological examination of renal sections in non-treated mice revealed normal histological architecture with normal glomerular tuft, Bowman's space and renal tubules. On the other hand, light microscopically examination of renal sections treated with monosodium glutamate for 10 and 14 days showed revealed variable degrees of alterations in response to the time of the treatment and compared to control. Treatment with monosodium glutamate for 10 days resulted in mild to moderate shrunken in glomerular tuft, narrow Bowman’s space and degenerated of some renal tubules with pyknotic nuclei together with mild to moderate aggregation of inflammatory cells and interstitial hemorrhage compared to control group, while loss of normal architecture, severe atrophied vacuolated glomerular tuft, with wide narrow Bowman’s space, and scattered marked to moderate aggregation of inflammatory cells were seen in renal sections from animals treated with monosodium glutamate for 14 days. Most renal tubules revealed severe degenerative change in their epithelial cell lining with pyknotic nuclei, and other remaining tubules revealed hyaline casts in their lumen (Fig. 4c).
Immunohistochemical analysis (Nuclear factor κB)
Cardiac, splenic, hepatic and renal section staining with Nuclear factor κB staining showed moderate increase in the NF κB level in animals treated with monosodium glutamate for 10 days compared to control group, while the treatment with monosodium glutamate for 14 days induced marked and highly significant raising in Nuclear factor κB level as evidenced by appearance of brown color compared to control group (Fig. 5) (Table 1).
Our investigation aimed to evaluate the effect of oral administration of monosodium glutamate on cardiac, splenic, hepatic and renal of male Swiss albino mice dependent on time using histopathological and immunohistochemistry studies. The experiment period extended for 14 successive days our study revealed that oral administration of monosodium glutamate resulted in histopathological alterations, and increased activity of NF κB, in all examined tissues, dependent on time of administration these were in agreement with (Ebaid & Tag, 2012; Tawfik and Al-Badr, 2012; AL-Mosaibih, 2013). These observed alterations in all examined tissues of animals treated with monosodium glutamate could be attributed to the presence of glutamate receptors on tissues. Glutamate is considered as the predominant excitatory neurotransmitters in in peripheral neural and non-neural tissues (Gill & Pulido, 2005). Likewise, Kalariti et al. (2005), Gill et al., (2007, 2008) stated that glutamate receptors have an important role in the pathophysiology of different organ systems and pathophysiology of syndromes and diseases such as epilepsy, stroke, schizophrenia, addiction, depression, anxiety, Alzheimer’s, Huntington’s, Parkinson’s, brain injury and heart diseases.
Another reason for tissues damage observed in our study could be attributed to elevation of free radical species, oxidative stress, lipid peroxidation, malondialdehyde and to reduction antioxidant enzymes as superoxide dismutase, catalase and glutathione peroxidase activities (Mohamed et al., 2022; Bhattacharya et al., 2011; Kumar & Bhandari, 2013; Hamza and AL-Harbi 2014; Mustafa et al., 2015; Diab & Hamza, 2016). It is well known that oxidative stress leads to activation of nuclear factor-jB (NF-jB) signaling pathway which is crucial for the regulation of many genes involved in inflammatory responses, such as tumor necrosis factor-a (TNF-a), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and caspase family of proteases leading eventually to cell death (Chen et al., 2012; Tugcu et al., 2010).
El-Shenawy and Al-Eisa (2010) and Diab and Hamza (2016), who found that administration of monosodium glutamate resulted in an increased superoxide radical production and other reactive oxygen species thereby induce oxidative stress in the hepatic tissues (Inuwa et al. 2011; Diab & Hamza, 2016). Increase levels of triglycerides, low-density lipoprotein cholesterol and volatile low-density lipoprotein cholesterol and decreasing high-density lipoprotein cholesterol was proposed as the cause of coronary heart disease (Kumar & Bhandari, 2013; Al-Harbi et al., 2014; Diab & Hamza, 2016). Diab et al. (2016) and El-Shenawy et al. (2010) stated that elevated levels of aspartate transaminase, alanine transaminase and lactate dehydrogenase enzyme activities and lipid profile as cholesterol, triglycerides levels could be the reason of the hepatocellular damage induced by monosodium glutamate.
Moreover, our result supported and explained by work done by Mohamed et al. (2022), who stated that administration of monosodium glutamate for 30 days and 60 days instigated a conspicuous expansion in AST and ALT and noticed a reduction in both all-out protein and albumin substance, these could be credited to the creation of oxidative stress that damage liver cells (El-Gharabawy et al., 2019).
Our present study indicated that oral administration of monosodium glutamate resulted in pathological lesions in the cardiac, splenic, hepatic and renal tissues as indicated by the microscopically examination. It also caused increase in the expression of level of NF κB in examined tissues.
Availability of data and materials
Aidaros, A. E. E., Ibrahim, A. A. S., Mohammed, H. O., & Hassan, N. H. (2019). Effect of monosodium glutamate on the cerebellar c0rtex of male albino rat and protective role of vitamin c. Zagazig University Medical Journals, 25(2), 250–260.
Aisha, D. A. (2014). Monosodium glutamate induced testicular lesions in rats (histological study). Middle East Fertility Society Journal, 19, 274–280.
Ali, H. S., El-Gohary, A. A., Metwally, F.G., Sabra, N.M., & El Sayed, A. A. (2012). Mono sodium glutamate-induced damage in rabbit retina: electroretinographic and histologic studies. Global Journal of Pharmacology, 6(3), 148–159. ISSN: 1992-0075.
Ali, A. A., El-Seify, G. H., El Haroun, H. M., & Mona Abd El-Mawla, M. S. (2014). Effect of monosodium glutamate on the ovaries of adult female albino rats and the possible protective role of green tea. Menoufia Medical Journal, 27, 793–800.
AL-Mosaibih, M A. (2013). Effects of monosodium glutamate and acrylamide on the liver tissue of adult wistar rats. Life Science Journal, 10(2s), 35–42. ISSN: 1097-8135. http://www.lifesciencesite.com.
Al-Harbi, M. S., El-Shenawy, N. S., & Al-Weail, N. O. S. (2014). Effect of monosodium glutamate on oxidative damage in male mice: modulatory of Vitamin C. Advances in Food Sciences, 36(4), 167–176.
Bancroft, J., & Gamble, M. (2002). Theory and practice of histological techniques (5th ed.). Churchil Livingstone.
Berkes, E. A., & Wossner, K. M. (2003). Monosodium glutamate. In D. D. Metcafe, H. A. Sampson, & R. A. Simon (Eds.), Food allergy: Adverse reactions to food and food additives (pp. 343–350).
Bhattacharya, T., Bhakta, A., & Ghosh, S. K. (2011). Long term effect of m0nosodium glutamate in liver of albino mice after neo-natal exposure. Nepal Medical College Journal, 13, 11–16.
Bojanic, V., Bojanic, Z., Najman, S., Savic, T., Jakovl-jevic, V., Najman, S., & Jancic, S. (2009). Diltiazem Prevention of toxic effects of monosodium glutamate on ovaries in rats. General Physiology and Biophysics, 28, 149–154.
Burrin, D. G., & Stoll, B. (2009). Metabolic fate and function of dietary glutamate in the gut. The American Journal of Clinical Nutrition, 90, 850–856.
Chen, J., Fok, K. L., Chen, H., Zhang, X. H., Xu, W. M., & Chan, H. C. (2012). Cryptorchidism-induced CFTR down-regulation results in disruption of testicular tight junctions through up-regulation of NF-jB/COX-2/PGE2. Human Reproduction, 27, 2585–2597.
Das, R. S., & Ghosh, S. K. (2011). Long term effects in ovaries of the adult mice following exposure to Monosodium glutamate during neonatal life. A histological study. Nepal Medical College Journal, 13(2), 77–83.
Diab, A.E.-A., & Hamza, R. Z. (2016). Monosodium glutamate induced hepatotoxicity and the possible mitigating effect of vitamin c and propolis. Journal of Advances in Medical and Pharmaceutical Sciences, 7(4), 1–10.
Egbuonu, A. C. C., Obidoa, O., Ezeokonkwo, C. A., Ezeanyika, L. U. S., & Ejikeme, P. M. (2009). Hepatotoxic effects of low dose oral administration of monosodium glutamate in male albino rats. African Journal of Biotechnology, 8(13), 3031–3035.
Ebaid, H., & Tag, H. (2012). Monosodium glutamate toxic effect on spleen structure and potentiality of recovery in adult albino rats. Egyptian Academic Journal Biological Science, 4(1), 1–8.
El-Shenawy, N. S., & Al-Eisa, R. A. (2010). Mechanism of organophosphorus insecticide chlorpyrifos toxicity in isolated rat hepatocytes. Egyptian Society of Clinical Toxicology Journal, 43, 87–112.
El-Gharabawy, R. M., Ahmed, A. S., & Al-Adhadh, Th. I. (2019). Ameliorating effect of Moringa against liver and kidney injury induced by monosodium glutamate. Annual Research & Review in Biology, 33(3), 1–10.
Eweka, A. O., Igibgbi, P. S., & Ucheya, R. E. (2011). Histo-chemical studies of the effects of Monosodium Glutamate on the liver of Adults Wistar Rats. Annal of Medical & Health Sciences Research, 1(1), 21–29.
Eweka, O. (2007). Histological studies of the effects of monosodium glutamate on the kidney of adult Wistar rats. International Journal of Health, 6(2), 1–6.
Garattiini, S. (2000). Glutamic acid, twenty years later. Journal of Nutrition, 130, 9018–9019.
Geha, R. S., Beiser, A., Ren, C., Patterson, R., Grammar, L. C., Ditto, A. M., & Harris, K. E. (2000). Review of allergic reaction to monosodium glutamate and outcome of a multicenter double blind placebo-controlled study. Journal of Nutrition, 130(4), 1032S-1038S.
Gill, S., Barker, M., & Pulido, O. (2008). Neuroexcitatory targets in the female reproductive system of the non-human prinates (Macca fascicularis). Toxicologic Pathology, 36, 478–484.
Gill, S., & Pulido, O. (2005). Glutamate receptors in peripheral tissues. Distribution, and implications for toxicology. Glutamate receptors in peripheral tissue: Excitatory transmission outside the CNS. Kluwer Academic.
Gill, S., Veinot, J., Kavanagh, M., & Pulido, O. (2007). Human heart glutamate receptors—Implications for toxicology, food safety, and drug discovery. Toxicologic Pathology, 35, 411–417.
Hamza, R. Z., & AL-Harbi, M. S. (2014). Monosodium glutamate induced testicular toxicity and the possible ameliorative role of vitamin E or selenium in male rats. Toxicology Reports, 1, 1037–1045.
Hassan, Z. A., Arafa, M. H., Soliman, W. I., Atteia, H. H., & Al-Saeed, H. F. (2014). The effects of monosodium glutamate on thymic and splenic immune functions and role of recovery (biochemical and histological study). Journal of Cytology and Histology, 5, 283.
Igwebuike, U. M., Ochiohu, I. S., Ihedinihu, B. C., Ikokide, J. E., & Idika, I. K. (2011). The effects of oral administration of monosodium glutamate (msg) on the testicular morphology and cauda epididymal sperm reserves of young and adult male rats. Veterinarski Arhiv., 81(4), 525–534.
Inuwa, H. M., Aina, V. O., Gabi, B., Aim, O. I., & Jaafaru, L. (2011). Determination of nephrotoxicity and hepatoxicity of monosodium glutamate (MSG) Consumption. British Journal of Pharmacology and Toxicology, 2(3), 148–153.
Kumar, P., & Bhandari, U. (2013). Protective effect of Trigonella foenum-graecum Linn. on monosodium glutamate-induced dyslipidemia and oxidative stress in rats. Indian Journal of Pharmacology, 45(2), 136–140.
Kalariti, N., Pissimissis, N., & Koutsilieris, M. (2005). The glutamatergic system outside the CNS and in cancer biology. Expert Opinion on Investigational Drugs, 14, 1487–1496.
Kumbhare, V., Gajbe, U., Singh, B. R., Reddy, A. K., & Shukla, S. (2015). Histological & histochmical changes in liver of adult rats treated with monosodium glutamate: A light microscopic study. World Journal of Pharmacy and Pharmaceutical Sciences., 4(04), 2278–4357.
Mohamed, M. A. E., El-Nahrawy, W. A. M., Zaher, A. M. E., & Amer, A. S. (2022). Therapeutic role of nanocurcumin versus monosodium glutamate toxicity. Egyptian Academic Journal of Biological Sciences, B. Zoology, 14(1), 55–65.
Mustafa, S. J., Salih, T. A., Yasseen, H. A., Marouf, B. H., & Mohammed, A. I. (2015). Effect of Monosodium glutamate on mice ovaries and the possible protective role of Vitamin C. Annalos of Applied Bio-SCience, 2(4), 101–105.
Peng, Q., Huo, D., Ma, C., Jiang, S., Wang, L., & Zhang, J. (2018). Monosodium glutamate induces limited modulation in gut microbiota. Journal of Functional Foods, 49, 493–500.
Ragab, E. E. (2018). The possible protective effect of vitamin C on monosodium glutamate induced renal toxicity in male albino rats. Egyption Journal Histology, 41, 386–396.
Samuels, S. (1999). The toxicity/safety of MSG: A study in suppression of information. Account Research, 6(4), 259–310.
Soria-Valles, C., Osorio, F. G., Gutiérrez-Fernández, A., De Los Angeles, A., Bueno, C., Menéndez, P., Martín-Subero, J. I., Daley, G. Q., Freije, J. M., & López-Otín, C. (2015). NF-kB activation impairs somatic cell reprogramming in ageing. Nature Cell Biology, 17, 1004–1013.
Tawfik, M. S., & Al-Badr, N. (2012). Adverse effects of monosodium glutamate on liver and kidney functions in adult rats and potential protective effect of vitamins C and E. Food and Nutrition Sciences, 3, 651–659.
Tugcu, V., Gedikbasi, A., Mutlu, B., Güner, E., Uhri, M., Andican, G., Ozbek, E., & Tasci, A. I. (2010). Increased testicular 8-hydroxy-20-deoxyguanosine (8-OHdG) and inducible nitric oxide synthetase (iNOS) and nuclear factor jB (NF-jB) expressions in experimental rat varicocele. Archivio Italiano Di Urologia e Andrologia, 82, 148–153.
Wu, G. (2010). Functional amino acids in growth, reproduction and health. Advances in Nutrition, 1, 31–37.
The author thanks, greatly honors, and expresses deep gratitude to the Egyptian Drug Authority Operations and Control Sector (Previously National Organization for Drug Control and Research (NODCAR), Cairo, Egypt, for providing their laboratory to carry out this study.
No funding was received from any person or organization for this study.
Ethics approval and consent to participate
All experimental procedures were conducted in accordance with the ethical standards and were approved by the Institutional Animal Care and Use Committee (IACUC) at National Organization for Drug Control and Research (NODCAR) (approval no. NODCAR/III/41/2019).
Consent for publication
The author declares that he/she has no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Hamad, S.R. Histopathological and immunohistochemical studies on the influence of orally administration monosodium glutamate, a food additive dependent on time in vivo. JoBAZ 83, 59 (2022). https://doi.org/10.1186/s41936-022-00322-6