ABSTRACT
Objective@#To examine the regulatory effect of ginsenoside Rg1 (G-Rg1) on endoplasmic reticulum stress and its effect on hepatocellular apoptosis in carbon tetrachloride (CCl4)-induced acute liver failure (ALF).@*Methods@#Forty healthy, adult male C57/BL mice were randomly divided into normal saline control (NS) group, G-Rg1 blank control (G-Rg1) group, CCl4 model (CCl4) group, and G-Rg1 preventive treatment (CCl4+G-Rg1) group, and an ALF mouse model was established by CCl4 induction. Blood and liver specimens were collected from all mice upon sacrifice at 12 hours post-intraperitoneal injection. Serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST) and total bilirubin (TBil) levels were determined using commercial test kits. The mRNA expression of glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP) was measured using real-time PCR. The protein expression of GRP78, CHOP, caspase12, and caspase3 were measured by Western blot. Histological changes in the liver were assessed by hematoxylin-eosin staining, and the expression of GRP78 and caspase3 was detected by immunohistochemistry. Hepatocyte apoptosis was determined using terminal transferase dUTP nick end labeling. Quantitative data were analyzed using one-way ANOVA, and subsequent pairwise comparisons were performed using the LSD-t method.@*Results@#Serum ALT, AST, and TBil levels in the CCl4+G-Rg1 group were significantly reduced compared with those in the CCl4 group (ALT: 691.30 ± 108.06 U/L vs 980.66 ± 110.29 U/L, F = 365.07, P < 0.05; AST: 195.40 ± 15.41 U/L vs 319.44 ± 89.32 U/L, F = 115.64, P < 0.05; TBil: 1.09 ± 0.11 mg/dl vs 1.56 ± 0.12 mg/dl, F = 211.29, P < 0.05). The relative mRNA expression of GRP78 and CHOP was significantly lower in the CCl4 + G-Rg1 group than in the CCl4 group (P < 0.05). The relative protein expression of caspase3, GRP78, caspase12, and CHOP was significantly reduced to different extents in the CCl4+G-Rg1 group compared with those in the CCl4 group (P < 0.05). The CCl4 + G-Rg1 group showed reduced liver tissue degeneration and necrosis compared with the CCl4 group. Furthermore, the CCl4+G-Rg1 group showed significantly fewer brown granules in the liver than the CCl4 group (P < 0.05), indicating that G-Rg1 preventive treatment reduced CCl4-induced hepatocyte apoptosis.@*Conclusion@#G-Rg1 prophylaxis can inhibit inflammation and reduce hepatocyte necrosis and apoptosis during CCl4-induced ALF. Its mechanism may involve the suppression of endoplasmic reticulum stress-related signaling molecules to alleviate hepatocyte endoplasmic reticulum stress and apoptosis. The results of this study suggest that G-Rg1 may inhibit liver inflammation and hepatocyte apoptosis through multiple targets to protect liver function.
ABSTRACT
<p><b>OBJECTIVE</b>To observe the effect of Rgl treatment on prognosis of alcoholic hepatitis using a rat model.</p><p><b>METHODS</b>Female Sprague-Dawley rats were radomly divided into four groups:unmodeled control, untreated model, Rgl-treated model, and dexamethasone (DXM)-treated model. The model groups were generated by intragastric injection of alcohol. The unmodeled control group was given an equal dosage of normal saline by the same route. After model establishment, the Rg1 treatment group and the DXM treatment group were administered a 120-hour treatment of Rgl or DXM; the unmodeled controls were administered normal saline on the same schedule. All rats were then fasted for 120 hours and venous blood samples were collected for detection of serum aspartate aminotransferase (AST), alanine transaminase (ALT), total bilirubin (TBil), albumin (Alb), tumor necrosis factor-alpha (TNFat) and interleukin 6 (IL-6). Markers of liver inflammation were measured by immunohistochemistry, western blotting, and real-time quantitative reverse transcription PCR. Fat and apoptosis indices were assessed by hematoxylin-eosin staining and TUNEL assay, respectively. The t-test and F test were used for statistical analyses.</p><p><b>RESULTS</b>The model group showed remarkably more liver steatosis (over one-third of the tissue) than the unmodeled control group, indicating proper establishment of alcoholic liver disease in the modeled rats. The AST, ALT, TBil, and IL-6 levels were significantly higher in the untreated model group than in the Rgl-treated group and the DXM-treated group. The values were significantly different between the Rg1-treated group and the DXM-treated group:ALT, 69.19+/-8.00 U/L vs.102.88+/-5.16 U/L; TBil, 0.36+/-0.07 µmol/L vs.1.20+/-0.18 µmol/L; IL-6, 126.50+/-6.50 U/ml vs.169.19+/-7.68 U/ml; TNFa, 268.31+/-13.19 µg/L vs.318.94+/-7.87 µg/L (all P less than 0.05). Expression of caspase3 and caspase8 was significantly higher in the model group than in the Rgltreated group and the DXM-treated group (both P<0.05). The apoptosis index was significantly lower in the Rgltreated group and the DXM-treated group than in the model group (both P<0.05). The mRNA and protein expression of caspase3, caspase8 and NF-kB were significantly lower in the Rgl-treated group and the DXM-treated group than in the model group (allP less than 0.05), and the levels of all were significantly lower in the Rgl-treated group cornered to the DXM-treated group (all P<0.05). Conehision In rats with alcoholic hepatitis, Rg1 can significantly relieve pathological injury, improve liver function by blocking the apoptotic pathway, and inhibit release of inflammatory cytokines.</p>