Effect of fucoxanthin on expression levels of PCSK9 mRNA in the liver. KK-Ay mice were fed with the AIN-93G diet with or without 0.2% fucoxanthin for 4 weeks. Total RNA was extracted from the liver and processed for quantitative real time PCR analysis as described under “Materials and Methods”. PCSK9 mRNA expression levels are normalized to β-actin levels. Data are presented relative to control group. Each value represents the mean ± standard error (n = 6). Asterisks show significant differences from the control group (** P < 0.01).