Skip to main content
. 2021 Sep 28;22(6):1381. doi: 10.3892/etm.2021.10817

Figure 3.

Figure 3

C21 increases the half-life of LDLR mRNA and reduced the secretion of PCSK9 protein. (A) C21 increased the half-life of LDLR mRNA. (B) After treatment for 2 h, C21 dose-dependently promoted the phosphorylation of ERK protein. PMA (5 ng/ml) was used as a positive control. (C-F) The ERK activation inhibitor U0126 counteracted the effects of C21 on LDLR protein, LDL uptake and half-life of LDLR mRNA in HepG2 cells. (G) C21 had little effect on the half-life of PCSK9 mRNA. (H and I) C21 decreased the secretion of PCSK9 protein into cell culture medium. BBR (40 µM) was used as a positive control. Results are presented as the means ± standard error of the mean, n≥5. *P<0.05, **P<0.01, ***P<0.001 vs. vehicle control by one-way ANOVA (Dunnett's multiple comparisons test). C21, euphornin L; LDL, Low density lipoprotein; LDLR, LDL receptor; PMA, phorbol 12-myristate 13-acetate; p-, phosphorylated; t-, total; PCSK9, Proprotein convertase subtilisin/kexin type 9; (c) PCSK9, PCSK9 protein in whole cell lysates; (m) PCSK9, PCSK9 protein in cell culture medium; BBR, berberine.