Monosodium glutamate (MSG) is a food additive with a wide range of biological effects but its high dose and
long period of using can cause a toxic effect on liver. Taurine is a derivative that produces antioxidant in many tissues
including liver. The current research concerned with biochemical, histopathological and ultra structural changes in rats
liver treated with MSG and throw light on the possible ameliorative effect of taurine – 150 male albino rats were divided
into five group each containing 30 rats (controls, taurine, MSG, therapeutic and protective group). Serum AST, ALT, ALP
and bilirubin (direct and total) were measured, as well as histopathological and ultrastructural changes in liver tissues were
examined in all groups. The rats received MSG orally in a dose 400 mg/Kg. B. wt for 8 weeks (MSG group), while taurine
induced orally in a daily dose at 1000 mg/Kg. B. wt alone (Taurine group) or after MSG (therapeutic) or before MSG
(protective) for the same period, in addition to frank control group received orally 2 ml saline per day during the
experiment. The results showed marked and gradual increase in the serum levels of AST, ALT, ALP and bilirubin (direct
and total) in MSG group as compared to control group. The histopathological structure of the same group showed hepatic
and local hemorrage as well as necrosis of hepatocytes with pyknotic nuclei after 4 weeks of the treatment, while after 8
weeks portal edema, thickening in wall of bile duct and portal infiltration were observed. Ultra structure examination in
the same group after 8 weeks showed hyaline degeneration; rough endoplasmic reticulum with irregular nuclear
membrane and cytoplasm rich in glycogen granules, Interestingly, the results showed a significant restore of hepatic injury
as evidenced by attenuation of hepatocellular enzyme and bilirubin release and reduction of hepatocyte necrosis and then
portal infiltration in therapeutic group reduction of hepatocyte necrosis and then portal infiltration therapeutic group.
While complete normalization in plasma ALT, AST, ALK and bilirubin levels with complete restore of histological and
ultra structural arrangement of hepatocyte were observed in protective group.
In conclusion, the results confirm the hepatotoxic effect of MSG and improve the hepatoprotective effect of taurine,
especially when it administrated as a protective substance than therapeutic. Also, we advice to add a suitable dose of
taurine to any food containing MSG as a food additive.