Stereospecific effects of catechin isomers on insulin induced lipogenesis in 3T3‐L1 cells

We studied the influence of (+)- and (-)-catechin contained in green tea on insulin induced lipogenesis in 3T3-L1 cells. In 14 days of culture with insulin, the intracellular triglyceride concentration and the activities of glycerophosphate dehydrogenase, a marker of adipose conversion, increased. The addition of 0.02 mg/ml (+)-isomer stimulated the accumulation of triglyceride induced by insulin, but the addition of the same concentration of (-)-isomer inhibited lipogenesis. The activities of glycerophosphate dehydrogenase were changed by (+)- and (-)-catechin in the same direction as the corresponding changes in triglyceride accumulation. These data suggest a biological significance of catechins, with opposite effects on lipid metabolism depending on the isomer.