Figure 3: Effect of berberine on human preadipocyte differentiation. Cells differentiated in the absence or presence of different concentrations of berberine over 16 days. The degree of differentiation was determined by Oil-Red-O staining. (a) Photomicrographs representing cells maintained in different concentrations of berberine: (A) control, (B) 0.1 μM berberine, (C) 1 μM berberine, (D) 10 μM berberine, ×100. (b) Absorbance value representing the mean ± SEM of the three separate experiments in six replicates. * , comparison between berberine-treated groups and control group, , comparison among berberine-treated groups.