Table 3.

Preclinical studies associating MSG exposure with cardiac toxicity

Mode of administration	Species	MSG dosage/day	Duration of administration (days)	MSG effect (vs. control)	Reference
Subcutaneous	Laka-UK mice	4 g/kg 8 g/kg	6	MSG induces dose-dependent oxidative stress in the cardiac tissue by: Significantly increasing lipid peroxidation and xanthine oxidase level in cardiac tissue; Significantly decreasing superoxide dismutase and catalase activities in cardiac tissue.	(Singh & Pushpa, 2005)
Subcutaneous	Newborn Wistar rats	4 g/kg	7 (from day 2 to 14 after birth, on alternate days)	Significantly increases total cholesterol, triglycerides levels and decreases HDL-cholesterol level; Increases serum lactate dehydrogenase, aspartate transaminase, and alanine transaminase activities; Increases malondialdehyde levels and reduce gluthatione, superoxide dismutase, catalase in cardiac tissue.	(Kumar & Bhandari, 2013)
Intraperitoneal	Albino rat (the exact type is not specified)	4 g/kg	9 (three times/week, for three consecutive weeks)	Significantly increases serum glucose, total lipids, triglycerides, total and LDL cholesterol levels and serum nitric oxide; Significantly increases thiobarbituric acid-reactive substances level and decreases in L-ascorbic acid, gluthatione, superoxide dismutase, catalase in cardiac tissue; Histopathological changes in cardiac tissue reported as necrotic lesions.	(Baky, 2009)
Intravenous	Wistar rat	0.5 g/kg 1.5 g/kg	Single administration	In normal rats: decrease in the heart rate (0.5 g/kg); bradycardia (1.5 g/kg); In rats with acute myocardial infarction, MSG 1.5 g/kg, i.v. induced ventricular tachyarrhythmias.	(Liu et al., 2013)