Protective effect of earthworm active ingredients against endoplasmic reticulum stress induced L-02 hepatocyte apoptosis / 中国中药杂志

This study focused on the protective effect of earthworm active ingredients (EWAs) on hepatocyte apoptosis induced by endoplasmic reticulum stress (ERS) in L-02 cells. The L-02 cells were cultured in vitro. The cell viability was measured with CCK-8, the apoptosis of L-02 cells was detected by flow cytometry, and the relevant protein and mRNA expressions were detected by Western blot and qPCR. According to the findings, tunicamycin (TM) could obviously reduce the survival rate of L-02 cells in a time-dependent and dose-dependent manner. Compared with normal group, the apoptosis rate in model group was significantly increased (<0.05 or <0.01). The protein and mRNA expressions of ERS-related signal molecules, such as GRP78, PERK, eLF2α, ATF4, CHOP and Bax, were significantly up-regulated (<0.05 or <0.01), while Bcl-2 was significantly down-regulated (<0.05 or <0.01). After the administration with different concentrations of EWAs, compared with model group, EWAs could significantly increase the survival rate ofL-02 hepatocyte and decrease the cell apoptosis rates. It could also reduce the protein and mRNA expressions of ERS-related signal molecules, such as GRP78, PERK, eLF2α, ATF4, CHOP and Bax, in a dose-dependent manner (<0.05 or <0.01) and increased the protein and mRNA expressions of Bcl-2(<0.05 or <0.01). These results showed that EWAs had a significantly protective effect on hepatocyte apoptosis induced by ERS in L-02 cells. Its mechanism may be related to the down-regulation of mRNA and protein expressions of GRP78, PERK, ATF4, eLF2α, CHOP and Bax, and the up-regulation, the relief of ERS and the promotion of the proliferation of impaired L-02 cells.

Protective effect of earthworm active ingredients against endoplasmic reticulum stress-induced acute liver injury in mice / 中国中药杂志

To study the protective effect of earthworm active ingredients(EWAs) against endoplasmic reticulum stress(ERS)-induced acute liver injury in mice. The model of liver injury was induced through intraperitoneal injection of 10%CCl4. Serum glutamic-pyruvic transaminase(ALT), glutamic-oxaloacetic transaminase(AST), superoxide dismutase(SOD) and glutathione peroxidase(GSH-PX) activity and malondialdehyde(MDA) concentration were detected by colorimetric method. Histological examination was performed through hematoxylin-eosin staining and light microscopy, and apoptosis was detected using terminal transferase dUTP nick end labeling. The expressions of ERS related proteins, including glucose regulated protein 78(GRP78), protein kinase R-like ER kinase(PERK), eukaryotic transcription initiation factor 2α(eIF2α), active transcription factor-4(ATF4) and CCAAT/enhancer binding homologous protein(CHOP), were measured by immunohistochemistry and Western blot. According to the results, compared with the model group,serological indexes in the high, middle and low doses of EWAs were significantly improved (P<0.05 or P<0.01), the extent of liver lesion was decreased and the degree of injury was significantly reduced, and that the liver index and the spleen index of mice were significantly changed(P<0.05 or P<0.01). In liver tissue, the expressions of GRP78 and CHOP were significantly decreased(P<0.05 or P<0.01). The protein expressions of GRP78, CHOP and its upstream signaling pathway PERK-eIF2-ATF4 were significantly decreased in each dose group(P<0.05 or P<0.01). In summary, EWAs has a significant protective effect on ERS-induced acute liver injury, and its mechanism may be correlated with the inhibition of oxidative stress and ERS, and down-regulation of ERS marker protein CHOP expression, andinhibition of apoptosis.