The Role Of Kaempferol In Acute Liver Failure Model And Endoplasmic Reticulum Stress-induced Hepatocyte Apoptosis

Objective:Acute liver failure is a syndrome that expresses as a large number of liver cell necrosis and severe liver dysfunction.It is caused by viruses,drugs,alcohol and other poisons. Patients progress to hepatic encephalopathy in the short time,and have a high mortality rate. Cell apoptosis induced by endoplasmic reticulum stress plays an important role in acute liver failure.Traditional Chinese Medicine treatment of acute and chronic liver failure have certain curative effect.In this paper,through the study of Chinese medicine extracts of different concentrations of kaempferol acting on acute liver failure in mice models,we observe the pathological changes and liverfunction.In addition,we observe the effect of Kaempferolonhuman normal hepatocyte line 7702 cells under the endoplasmic reticulum stress.We will investigate the effect and mechanism of kaempferol apoptosis in acute liver failure from the endoplasmic reticulum stress areas.From the perspective of endoplasmic reticulum stress,we will explore the effect and mechanismthat kaempferol acting on acute liver failure model and human normal hepatocyte line 7702 cells.Methods:Animal experimental groups werecontrol group,acute liver failure model groupand low、medium and high dose of kaempferol group(including 5mg/kg、10 mg/kg and 20 mg/kg).8 mice in each group.D-Gal N/LPS were injected intraperitoneally to estabilish the the acute liver failure model in male C57 BL / 6 mice.HE staining were tested for liver histology injury,serum ALT and AST levels were detected to reflect the liver function.In order to build up hepatocyte apoptosis model,we used endoplasmic reticulum stress inducer tunicamycin to induce 7702 cells apoptosis.7702 cells were incubated with different concentrations of Kaempferol, including 0.01μmol/L,0.1μmol/L,1μmol/L. Morphological changes were observed by microscope.Cell viability was measured by MTT method.Lactate dehydrogenase(LDH) activity in cell supernatant was determined by LDH assay kit.Apoptosis was measured by flow cytometry.The key protein expression of CHOP, a special apoptosis marker of endoplasmic reticulum stress,was detected by western blot.Results:The experimental results showed that compared with model group,kaempferol intervention group improved the pathological injury of liver tissue,different level significantly reduced in mice serum ALT and AST level.(Serum ALT level:acute liver failure model group,1858.9±515.2IU/L,different kaempferol intervention groups, 186.5±63.1 IU/L、254.9±82.86 IU/L、1413.1±327.1 IU/L,low and medium dose of kaempferol group compared with model group,P<0.01.Serum AST level:acute liver failure model group,1961.4±474.8 IU/L,different kaempferol intervention groups, 326.5±91.2 IU/L、331.9±65.4IU/L、1928.8±256.6 IU/L,low and medium dose of kaempferol group compared with model group,P<0.01).As the concentration rise,the protective effect was weakening.Compared to tunicamycin-induced hepatocyte apoptosis group,low concentrations ofkaempferol(0.01μmol/L,0.1μmol/L,1μmol / L) significantly inhibited the endoplasmic reticulum stress-induced hepatocyte apoptosis.Kaempferol improved cell morphology,increased liver cell survival rate(tunicamycin model group, 80.14 ± 8%; 0.01μmol/L kaempferol intervention group,96.16 ± 10%,0.1μmol/L kaempferol intervention group,91.43 ± 9.1%,1μmol/L kaempferol intervention group, 87.84 ± 6.9%,compared with model group,P<0.01).Reduced the LDH level released from 7702 cells(tunicamycin model group,398.5±30.8U; 0.01μmol /L kaempferol intervention group,89.9±21.4U,0.1μmol / L kaempferol intervention group,95.1±8.9U, 1μmol / L kaempferol intervention group,120.5±24.2,compared with model group,P<0.01).Reduced the 7702 rate of apoptosis(tunicamycin model group,4.58 ± 0.9%;0.01μmol/L kaempferol intervention group,1.18 ± 0.48%,0.1μmol/L kaempferol intervention group,1.97 ± 0.32%,1μmol/L kaempferol intervention group,2.63 ± 0.16%, compared with model group,P<0.01),and significantly reduced the expression of CHOP protein.Conclusion:Endoplasmic reticulum stress is an important way to cause apoptosis in acute liver failure.The role of kaemperol in acute liver failure model may improve the pathological injury of liver tissue and reduced in mice serum ALT and AST level.Low concentrations of kaempferol may inhibit endoplasmic reticulum stress-induced 7702 cells apoptosis by decreased the expression of CHOP,kaempferol may be a new intervention drug to protect liver damage induced by liver disease.