The effect of methionine supplementation of the AIN-93G semi-synthetic diet on the levels of homocysteine and lipids in experimental rats.

OBJECTIVES: The studies were carried out on 36 growing albino Wistar rats. PARTICIPANTS/MEASUREMENTS: The animals were randomly divided into six equinumerous groups (six rats per group), and were fed six different diets for 42 days. The control group (I) was fed with AIN-93G semi-synthetic diet, whereas groups II-VI were fed with AIN-93G semi-synthetic diet supplemented with: 2, 4, 8, 16 and 32 g of methionine/kg diet, respectively. There were assessed enzymatically, in rats' blood serum, the contents of homocysteine, total cholesterol, HDL fraction and triacyloglicerols. In addition, the LDL+VLDL cholesterol content was calculated. RESULTS: The methionine content of the diet was found to be highly positively correlated with the homocysteine content (r = 0.981) and negatively correlated with the triacylglycerols content (r = -0.916) of the experimental animals' blood serum. CONCLUSION: In the blood serum of rats fed the highest-methionine diet (32 g methionine/kg diet), the homocysteine content was significantly higher, as were the levels of total cholesterol and its HDL fraction, while the triacylglycerols content was lower as compared to the values obtained for rats fed other diet types.