Myricetin Induces Apoptosis and Protective Autophagy through Endoplasmic Reticulum Stress in Hepatocellular Carcinoma

Figure 2

Myricetin-mediated ER stress participated in myricetin-induced apoptosis in human hepatocellular carcinoma cells. (a) Morphological changes in SMMC-7721 and Hep3B cells were observed under an inverted light microscope (100×) after treatment with 100 μM myricetin for 24 h. (b). SMMC-7721 and Hep3B cells were incubated with various concentrations of myricetin and tunicamycin (5 µg/ml) for 24 h and the expression of BiP, eIF2α, p-eIF2α, IRE1α, and CHOP was detected by western blotting. (c) SMMC-7721 and Hep3B cells were treated with various concentrations of myricetin for 24 h. Then, the level of intracellular Ca²⁺ was measured using flow cytometry with Fluo-3 AM staining. (d) Control siRNA or CHOP siRNAs were transfected into SMMC-7721 and Hep3B cells. After cells were exposed to vehicle or 100 μM myricetin for 24 h, the protein levels of PARP and CHOP were validated by western blotting. (e) (f). Cells were treated and then harvested for apoptosis detection using Annexin V and PI staining with flow cytometry. Representative data from three independent experiments in triplicate are shown as the mean ± S.D. ^/#, ^/##.

(a)

(b)

(c)

(d)

(e)

(f)