Sesamin, a Naturally Occurring Lignan, Inhibits Ligand-Induced Lipogenesis through Interaction with Liver X Receptor Alpha (LXRα) and Pregnane X Receptor (PXR)

Figure 1

Lipid accumulation in differentiated HepaRG cells and transcriptional assays of 3 × LXRE and SREBP-1c reporter activity in HepG2 cells to determine the effects of sesamin (SSM) and T0901317 (T090)-mediated activation of LXRα. (a) Differentiated HepaRG cells were repeatedly exposed to (A) solvent, (B) 10 μM T090, (C) 10 μM T090 + 5 μM SSM, and (D) 10 μM T090 + 10 μM SSM for 14 days. Lipid accumulation was then assessed using Oil Red O staining, which allows the detection of triglycerides and cholesterol esters. HepaRG cells were observed and photographed under a phase‐contrast microscope (original magnification ×400). Oil red O dye was then extracted using isopropanol and quantified with a microplate reader at 510 nm. Values represent the mean ± SE; n = 3; compared with control or T090-treated groups as indicated. HepG2 cells were cotransfected with a LXRα expression plasmid and (b) 3 × LXRE-Luc and (c) SREBP-1c-Luc reporter genes and treated with 20 or 40 μM SSM alone or in combination with 10 μM T090 for 24 h. Data represent the mean ± SE; n = 4; ; compared with control or T090-treated groups as indicated.

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