Protective effect of blueberry anthocyanins in a CCL4-induced liver cell model

This study investigates the protective effects of blueberry anthocyanins against acute liver injury. Cyanidin-3-glucoside, delphinidin-3-rutinoside, and malvidin-3-galactoside, the main monomers among blueberry anthocyanins, play important roles in cell survival and in increasing the level of the main cellular antioxidant. Results of the cell proliferation assay showed that different concentrations of blueberry anthocyanins protected the human embryonic-liver L-02 cells against CCl4-induced injury in a dose-dependent manner. After 48 h of incubation, the anthocyanins protected the human embryonic-liver L-02 cells, with IC50 of 6.2 × mg/L. Cell-clone formation inhibition assay demonstrated that cell clones increased with increased concentration of anthocyanins. Propidium iodide (PI) staining and DNA ploidy analysis showed that anthocyanins can decrease cell cycle in the G1 phase, which leads to a reduced percentage of hypodiploid cells, in a dose-dependent manner. Moreover, annexin V-FITC/PI staining analysis showed a dose-dependent effect of anthocyanins on late-apoptotic and necrotic cells. Western blot assay showed a gradual decrease in caspase-3 protein expression levels with the increase in anthocyanin concentration. These findings support the protective effects of blueberry extract against acute liver injury.