Fig. 1.

Stearoyl-CoA desaturase-1 (SCD1) knockdown decreases de novo lipogenesis in HepG2 cells. A: SCD1 protein expression was evaluated by Western blotting in HepG2 cells transfected with negative control (Ctrl) or SCD1-targeting small interfering (si) RNA (siSCD1). Protein levels measured by densitometry were normalized against GAPDH and presented relative to negative control. B: HepG2 cells transfected with negative control (Ctrl) or SCD1-targeting siRNA (siSCD1) were incubated with [¹⁴C]acetate. Incorporated radioactivity was measured by thin layer chromatography in total lipids as well as in lipid fractions, including triacylglycerols and diacylglycerols, and presented as counts per minute (CPM) of [¹⁴C]lipids per microgram of total protein. C: the expression of proteins involved in lipid metabolism [precursor and mature sterol receptor element binding protein-1 (SREBP-1), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC)] was evaluated by Western blotting in SCD1-deficient HepG2 cells. Protein levels measured by densitometry were normalized against GAPDH and presented relative to negative control. Each histogram presents the means ± SD of 5 independent experiments. *P < 0.05, **P < 0.002, and ***P < 0.001.