Effects of flavan-3-ols on expression of mitochondrial biogenesis-related protein in insulin-resistant 3T3-L1 adipocytes. RT-PCR analysis of mRNA levels of, (a) PGC-1α, (b) NRF1, and (c) Tfam. (d) Western blot analysis of expression of SirT1 and PGC-1α. Fully differentiated 3T3-L1 adipocytes were treated with Dex for 48 h in the presence or absence of flavan-3-ols or rosiglitazone. Con, normal differentiated 3T3-L1 adipocytes; Mod, Dex alone treated differentiated 3T3-L1 adipocytes; Rosi, rosiglitazone; C, catechin; EC, epicatechin; PB7, procyanidin B7; PB6, procyanidin B6; PB3, procyanidin B3; PB1, procyanidin B1. Values are shown as Mean ± SD of three independent triplicate experiments (n = 3). # p < 0.05 and ## p < 0.01 compared with normal differentiated adipocytes; * p < 0.05 and ** p < 0.01 compared with Dex only treated adipocytes.