Enhanced Platelet Aggregation, Hyperinsulinemia and Low Testosterone Level in Monosodium Glutamate Obese Rats

The aim of this study was to assess the effect of obesity induced by high fat diet and monosodium glutamate (MSG) on platelet aggregation, hematologic parameters, plasma insulin and testosterone in adult male rats. Male rats were distributed into 3 groups: Control group, receiving control diet. High fat diet (HFD) -induced obesity group, receiving high fat diet. Monosodium glutamate (MSG) - treated group, receiving control diet and MSG in a dose of 150 mg/Kg b.w. daily by gavage. The HFD and MSG- obese rats showed increased values of final body weight (BW), body mass index (BMI) and Lee index as well as the percentage gain of these parameters compared with their matching controls. Erythrocyte count, hemoglobin content, the total and differential leukocyte count, the platelet count and the platelet indices (mean platelet volume, and platelet distribution width) were not significantly changed in the different studied groups compared to their matched control group. However, ADP-induced platelet aggregation was significantly increased in the MSG-obese rats as compared to either control rats or HFD-obese rats. Radioimmunoassay measurement revealed significant increase in plasma insulin level in MSG-obese group compared to their matched control group. In contrast, plasma testosterone level was significantly decreased in MSG-obese group compared to their matched control and HFD-obese groups. A significant positive correlation was displayed between BMI and ADP-induced platelet aggregation in the studied rats. Moreover, a positive correlation was observed between plasma insulin level and ADP-induced platelet aggregation in MSG-obese rats. Ingestion of MSG in adult male rats produced platelet hyperaggregation, hyperinsulinemia, hypoandrogenemia and hence could be responsible for the initiation of atherothrombosis. These findings raise a concern about the safety of MSG use