Monosodium glutamate genotoxicity in mice

ABSTRACT

The genotoxic effect of monosodium glutamate [MSG] was investigated usingdifferent cytogenetic parameters. Different dose levels were studied rangingfrom 0.8 g/kg b. wt. [amount typically added to food] to 1.6, 3.2 g/kg b.wt. Single intraperitoneal treatment with MSG at the tested concentrationshad no effect with respect to the induction of sister chromatid exchanges[SCEs] in mouse bone-marrow cells. The same doses showed normal percentage of micronucleated polychromatic erythrocytes [PEs] after oral treatment bygavage for seven consecutive days. Marrow toxicity was not observed as indicatedby normal percentage of PEs as compared with that in the untreated mice. With respect to chromosomal aberrations in bone marrow cells, gaps were foundto be the most sensitive type of aberrations induced after oral treatment[gavage and feeding] with the different concentrations of MSG. The percentageof the induced aberrations was found to be nonsignificant after excluding thenumber of metaphases with chromatid and chromosome gaps as compared with thenegative control. In germ cells oral treatment by gavage at the doses of 1.6,3.2 g/kg b. wt. MSG induced significant percentage of chromosomalaberrations [P <0.05] in 1ry spermatocytes after 2 and 3 weeks as comparedwith the negative control. The same result was observed in groups of mice fed0.8 g MSG/kg1 b. wt. 1/day mixed with the diet for 2 and 3 months. Thedoses 1.6, 3.2 g/kg b. wt. MSG induced also significant percentage ofabnormal sperms. Such percentage reached 4.12 +/- 0.1 [P <0.05] and 8.55 +or- 0.76 [P <0.01] compared with 2.38 +/- 0.21 for the negative control. Mitomycin C at 1 mg/kg b. wt. [positive control] induced a much highereffect 13.36 +/- 0.78 [P <0.01]