Studies on effect of monosodium glutamate (MSG) on various fractions of lipids and certain carbohydrate metabolic enzymes in liver and blood of adult male mice.

Monosodium glutamate (MSG) was administered subcutaneously to adult male mice for 6 days at dose levels of 2, 4, and 8 mg/g body wt. Dose levels above 4 mg/g body wt. showed significant increase in content of liver total lipids, phospholipids, triglycerides and free fatty acids, 31 days after the last injection. Blood glutamate level was significantly increased in all the groups but blood glutamine was increased in 4 and 8 mg/g body wt. groups (Groups III and IV) only. Blood pyruvate and glucose was significantly increased whereas liver glycogen and blood lactate was decreased in group III and IV. Activity of lactate dehydrogenase was significantly reduced both in serum and liver but the activity of glucose-6-phosphate dehydrogenase was significantly increased in RBC and liver at dose levels of 4 and 8 mg/g body wt. All these observations are suggestive of the fact that carbohydrate metabolism is shifted towards lipogenesis and hence leads to hyperlipidemia.