Fig. 9

Effect of IIAEK on fluorescently labelled cholesterol uptake in Caco-2 cells with knockdown of human cadherin 17 (CDH17). Caco-2 cells were cultured in 6-well plates for 14 days post-confluence. CDH 17 (20 nM) or negative control siRNA (20 nM) was introduced into the cells for 72 h. After 72 h of introduction, the cells were reintroduced with these siRNAs for 72 h. Subsequently, the cells were treated with serum-free medium containing 2 mM IIAEK (Ile-Ile-Ala-Glu-Lys) or the vehicle for 24 h. After removing the medium, the cells were incubated with a serum-free medium containing fluorescently labeled cholesterol (NBD-cholesterol) micelle for 1 h. After incubation, the cells were washed and cultivated to measure the fluorescent intensity of NBD-cholesterol. (a) CDH 17 mRNA levels. (b) Effect of IIAEK on NBD-cholesterol uptake in Caco-2 cells introduced with negative control siRNA. (c) Effect of IIAEK on NBD-cholesterol uptake in Caco-2 cells introduced with CDH17 siRNA. (a–c) n = 3/group. Data are presented as mean ± standard error of the mean (SEM). Statistical significance was calculated using an unpaired Student’s t-test. Asterisks indicate significant differences between the experimental groups (* p < 0.05).