Changes in lipolysis and hormone-sensitive lipase expression caused by procyanidins in 3T3-L1 adipocytes

OBJECTIVE: To find out whether lipid stores are influenced by phenolic comp ounds in wine. DESIGN: Differentiated 3T3-L1 cells were treated with catechin, epicatechin or procyanidin extracts with different degrees of polymerization at 150 mu M for different periods of time (0.5-24 h). SUBJECTS: Cell line 3T3-L1. MEASUREMENTS: Cellular viability, glycerol-phosphate dehydrogenase activity , glycerol release in the medium, HSL mRNA levels, triacylglycerols and pro tein. RESULTS: Catechin, epicatechin and procyanidin extracts were not toxic for the 3T3-L1 cells in the conditions assayed. Glycerol-3-phosphate dehydrogen ase activity was markedly decreased by 150 mu M procyanidin extracts. The r elease of glycerol into the medium was increased in 150 mu M procyanidin ex tract-treated cells and reached a plateau after 15h exposure. Procyanidins caused a time-dependent reduction in the HSL mRNA levels. CONCLUSIONS: These results suggest that procyanidins from grape and wine af fect lipid metabolism whilst their monomers (catechin and epicatechin) do n ot. This effect is more pronounced when the degree of polymerization is hig her. Procyanidin extracts cause a time-dependent reduction in the HSL mRNA levels, inhibit triacylglycerol synthesis and also favour triacylglycerol h ydrolysis until the HSL mRNA had reached very low levels.