Anti-atherosclerotic activity of catechins depends on their stereoisomerism.

In terms of stereochemistry, catechins are divided into two groups: (-) epi forms (2R, 3R) and (-) forms (2S, 3R). Most of the catechins present in green tea are (-) epi forms (2R, 3R). Under the influence of high temperatures, in anaerobic conditions, as a result of epimerization the proportion of the (-) form (2S, 3R) increases. The data indicate that the presence of thermally modified catechins in the diet more efficiently reduces the development of atherosclerosis in apoE knockout mice than the presence of native catechins. The addition of the thermally modified formulations to the high-fat diet resulted in a reduction of the area of atherosclerotic lesions by about 28% (en face method) and 45% (cross-section method) compared to the group fed the high-fat diet without catechins. Furthermore, the body weight gain and plasma TBARS concentration in mice fed a diet with the addition of catechins depends on the degree of epimerization of catechins and decreases with increasing content of catechins belonging to the (-) form (2S, 3R). Moreover, plasma HDL cholesterol concentration in mice depends on catechins' stereoisomerism and increases along with the increasing content of catechins belonging to the (-) form (2S, 3R).