Figures (4)  Tables (5)
    • Figure 1. 

      Metabolic reactions for the biotransformation of monosodium glutamate (MSG) in different body organs.

    • Figure 2. 

      MSG toxic effects on human functions.

    • Figure 3. 

      MSG could lead to metabolic syndrome.

    • Figure 4. 

      Nutraceuticals and natural products protective effect against MSG toxic actions in human functions.

    • Separation
      and extraction
      Chemical synthesisFermentation
      MaterialsWheat
      gluten
      AcrylonitrileSelected
      microorganism,
      carbohydrates
      and ammonia
      Yield ↑×
      Time ↓×
      Purity ↑×
      Cost ↓×
      Environmentally friendly ↑××

      Table 1. 

      The advantages or disadvantages of various methods for producing MSG.

    • DiseasesDosage/daySpeciesEffectsReferences
      ObesityInject MSG (4 mg/g)MiceInduced obesity[18]
      Mixed with 3, 6 and 9 g of MSGWistar ratsIncreased in body weight gain[88]
      S.c. 4 mg/gAdult Wistar ratsInduced obesity[23]
      2.2 ± 1.6 g/dHealthy Chinese adultsInduced overweight[26]
      250 g of MSG for food preparation
      for 10 d
      Families from rural area of ThailandOverweight[27]
      NAFLDS.c. 2 mg/gICR miceInduced obesity and diabetes with steatosis and steatohepatitis resembling human NAFLD and NASH with pre-neoplastic lesions[33]
      Drinking water containing
      0.64 g/L MSG
      Female C57BL/6J miceInduced dyslipidemia and markers of insulin resistance[19]
      Insulin resistantS.c. 4 g/kgNewborn Wistar ratsDeveloped glucose intolerance[20]
      T2DMS.c. 4 mg/gMale DIAR miceObesity, diabetes and macrovesicular steatohepatitis[21]

      Table 2. 

      List of the effect of MSG on metabolic syndrome.

    • DiseasesDosage/dSpeciesEffectsReferences
      Nervous systemS.c 4 mg/gMale Wistar ratsIncreased brain extracellular Glu level and produced hyperexcitability and motor behavior alterations[30]
      3,200 mg/kg/dInduced neurodevelopmental toxicity[9]
      2 mg/g or 4 mg/gMice and ratsCaused acute neuronal necrosis[31]
      I.p.500 mg/kgAdult male Fischer-344 ratsAltered the dopamine content in adult rats[32]
      I. p. 2 g/kgMale Wistar ratsLead to long-term memory impairment[34]
      Mice and ratsExhibited peripheral insulin resistance, cognitive deficits, and a reduction in the total hippocampal volume with decreased neuron count in the DG, CA3, and CA1 subfields.[35]
      Kidneys4 mg/gAdult albino Wistar ratsThe cortex of the kidneys developed variable pathological changes[37]
      3 g/kgMale Wistar ratsProduced hyperfiltration with increased tubular reabsorption of Na, K and water[38]
      2 mg/gWistar male ratsThe renal handling and toxicity mainly related to oxidative stress and metabolism[39]
      3 g/kgMale Wistar ratsOccurred the renal pathologic changes, intrarenal oxidative stress and reduction of nitric oxide excretion[40]

      Table 3. 

      The effect of MSG on nervous system and kidneys.

    • DiseasesDosage/daySpeciesEffectsReferences
      Cardiovascular diseases4 mg/gNewborn ratsResulted in typical adult life MetS and oxidative stress with significant increase in ET-1 and MMP-1 with aortic vasculopathy[41]
      4 g/kgNeonatal Wistar ratsInduced dyslipidemia and oxidative stress[42]
      I.v 1.5 g/kgWistar ratsInduced bradycardia[43]
      Fertility and fetal development60 and 120 mg/kgAdult male ratsSignificant damage to the reproductive system[45]
      6, 17.5 and 60 mg/kgMature male Wistar ratsInduced testicular toxicity and reduce the oxidative stress on testis tissues[46]
      S.c. 4 g/kgMale and female Wistar ratsMale rats were more susceptible to induce metabolic alterations[47]
      0.8, 1.6 and 2.4 mg/kg BW/dayFemale virgin albino ratsSuppressed the female reproductive function by impairing the functions of ovary and uterus[48]
      S.c 4 g/kgPregnant Wistar ratsDecrease in oocyte count and increase the total primordial and atretic follicles[49]
      0.2 g/kgFemale Wistar ratsDecrease in primary follicle count and increased in atretic follicle count[50]
      CancerS.c 400 mg/kgNewborn male Wistar ratsIncreased tumor growth[51]
      S.c 2 mg/gThe pregnant ICR miceHighly susceptible to AOM-induced colorectal carcinogenesis[52]
      Immune systemHuman lymphocytes250, 500, 1,000, 2,000, 4,000 and 8,000 μg/mLShowed genotoxic to the human peripheral blood lymphocytes[55]
      1−100 mMB cellsInduced apoptosis in naïve and memory human B cells[56]
      I.p. 4 mg/gAdult male and female Sprague-Dawley ratsInduced immune derangements[57]
      2 mg/gC57BL/6J male miceImpaired the defense mechanism against invasion of pathogenic microbes[58]
      I.p.4 mg/gMale Wistar ratsTriggered the thymocyte apoptosis[59]
      4 mg/gInduced thymocyte apoptosis[60]
      Newborn miceDestructed the mouse arcuate nucleus[61]
      Miscellaneous ellaneous effects300 mg/kgMale NMRI miceInduced hyperalgesia[63]
      4 mg/gNewborn ratsAffected the thyroid function[64]
      2 mg/gNewborn miceInduced obesity and recognition memory deficits[65]
      MiceExhibited endocrine dysfunctions[66]
      2 or 4 g/kgMale Wistar ratInfluenced cortical excitability[67]
      RatsCaused behavioral deficits[69]
      4 mg/gAdult male Wistar ratsInduced oxidative stress and apoptosis in thymocyte[60]
      0.5% MSG and 1% MSGAPPswe, PSEN1dE9-85Dbo/J transgenic mice and WT miceAccelerated AD-like pathophysiology in a
      mouse model of AD
      [70]
      S.c 3 mg/gPregnant Hannover-Wistar female ratsReduced locomotion[71]
      1.0 g/LWistar Albino ratsIncreased CNS excitability[72]
      3.0 and 3.5 mg/gWistar ratsDecreased motor coordination and the estimated total number of Purkinje cell of rats[73]
      0.05%, 0.1%, 0.2%
      and 0.5%
      Male Wistar ratsInduced pancreatic acinar cells injury[74]
      250, 500, 1,000, 2,000, 4,000 and 8,000 μg/mLHuman lymphocytesInduced genotoxicity[55]
      100 μM, 250 μM, 2.5 mM and 25 mM3T3-L1 preadipocytes cellsChanges in cell proliferation and lipid accumulation[75]
      2.5 gTwo young womenInduced asthma[76]
      SubjectsInduced asthma and make recognition difficult[77]
      75 or 150 mg/kg14 healthy menInduced headache and craniofacial pain[78]
      Induced chronic pain[79]
      1,227 Chinese subjectsIncreased the risk of SDB in Chinese adults[80]
      1,227 Chinese men and womenIndependent BP-increasing effects[81]

      Table 4. 

      MSG-induced miscellanious injuries.

    • Target MSG-induced diseasesCompoundDose or concentrationExperimental modelEffectsReferences
      Metabolic syndromeVitamin D0.2 mcg/kgFemale ratsSuppressed body weight[82]
      Probiotics109 CFU/kgNewborn ratsRecovery of lipid metabolism and prevention of the obesity development[83]
      Pentamethylquercetin5, 10 and 20 mg/kgObese miceAmeliorated obesity phenotypes and improved metabolic disorders[84]
      Quercetin5 mg/kgC57BL/6J miceReduced the hypothalamus damage and the expression of liver RetSat[85]
      n-6/n-3 PUFAsn-6/n-3 fatty acid ratio of 1.2: 1.0Female micePrevented metabolic dysfunction[86]
      Quercetin75 mg/kgMale Wistar ratsNormalized serum lipid and glucose profile[87]
      (p-CIPhSe)210 mg/kgNewborn Wistar ratsReduced hepatotoxicity[89]
      Berberine150 mg/kgNewborn ratsAlleviated postnatal metabolic disorders associated vascular endothelial dysfunction[41]
      Polyphenol-rich extract of Syzygium cumini leaf500 mg/kgObese ratsImproved peripheral insulin sensitivity[90]
      Nervous systemAllium sativum powder200 mg/kgMale Wistar albino ratsAnti-oxidative stress and apoptosis[91]
      Calendula officinalis L. flowers100 and 200 mg/kgAdult female Wistar ratsAntioxidant and anti-inflammatory[92]
      Rosemary extract and/
      or fluoxetine
      50 mg/kgMale Sprague-Dawley ratsAntioxidant and anti-inflammatory[93]
      KidneyZinc oxide nanoparticlesReduced the level of intracellular peroxidation by enhancing antioxidant capacity[95]
      Nigella sativa seeds30 g/kgMale adult albino ratsRebalanced LPO and TAC, antioxidant and cytoprotective activities[96]
      OthersHibiscus sabdariffa extract180 mg/kgAdult ratsReduced oxidative stress and cellular apoptosis[97]
      N-Acetylcysteine500 μMC6 cellsProtected C6 stellate cells[98]

      Table 5. 

      Protective effects of some plants or natural products against various MSG negative health effects.