Effect of rutin and quercitrin on the trafficking of NPC1 protein between the ER and the Golgi. The fibroblasts derived from a healthy donor (WT), patient 1 (P1), patient 2 (P2), patient 3 (P3), and patient 4 (P4) were treated for 24 h with rutin (10 mM) or quercitrin (10 mM). The cellular lysates were immunoprecipitated with anti-NPC1 and further treated or not treated with endo H. The immunoprecipitates were subjected to SDS-PAGE for NPC1 analysis (A). The ratio of the complex (NPC-c) versus mannose-rich (NPC-h) forms of the NPC1 protein were depicted and the values were normalized to the untreated group (B). Ordinary one-way ANOVA, ns p > 0.05 versus untreated group, S.E.M., and n = 3.