Effect of ADHI on hepatic stellate cell activation and liver fibrosis in mice.

The relationship between alcohol dehydrogenase (ADH) and liver fibrosis has been studied, but the mechanism of ADH involvement in liver fibrosis remains unclear. The aim of the present study was to explore the role of ADHI, the classical liver ADH, in hepatic stellate cell (HSC) activation and the effect of 4-methylpyrazole (4-MP), an ADH inhibitor, on liver fibrosis induced by carbon tetrachloride (CCl4) in mice. The results showed that overexpression of ADHI significantly increases proliferation, migration, adhesion and invasion rates of HSC-T6 cells as compared with controls. When HSC-T6 cells were activated by ethanol, TGF-ß1 or LPS, the expression of ADHI was elevated significantly (P < 0.05). Overexpression of ADHI significantly increased the levels of COL1A1 and α-SMA, markers of HSC activation. Moreover, the expression of COL1A1 and α-SMA was decreased significantly by transfection of ADHI siRNA (P < 0.01). In a liver fibrosis mouse model ADH activity increased significantly and was highest in the 3rd week. The activity of ADH in the liver was correlated with its activity in the serum (P < 0.05). 4-MP significantly decreased ADH activity and ameliorated liver injury, and ADH activity was positively correlated with the Ishak score of liver fibrosis. In conclusion, ADHI plays an important role in the activation of HSC, and inhibition of ADH ameliorates liver fibrosis in mice.

The CYP2E1 inhibitor Q11 ameliorates LPS-induced sepsis in mice by suppressing oxidative stress and NLRP3 activation.

Sepsis is an infection-induced, multi-organ system failure with a pathophysiology related to inflammation and oxidative stress. Increasing evidence indicates that cytochrome P450 2E1 (CYP2E1) is involved in the incidence and development of inflammatory diseases. However, a role for CYP2E1 in lipopolysaccharide (LPS)-induced sepsis has not been completely explored. Here we use Cyp2e1 knockout (cyp2e1-/-) mice to determine if CYP2E1 could be a therapeutic target for sepsis. We also evaluated the ability of Q11, a new specific CYP2E1 inhibitor, to prevent and ameliorate LPS-induced sepsis in mice and in LPS-treated J774A.1 and RAW264.7 cells. Cyp2e1 deletion significantly reduced hypothermia, multi-organ dysfunction and histological abnormalities in LPS-treated mice; consistent with this finding, the CYP2E1 inhibitor Q11 significantly prolonged the survival time of septic mice and ameliorated multi-organ injury induced by LPS. CYP2E1 activity in liver correlated with indicators of multi-organ injury, such as the level of lactate dehydrogenase (LDH) and blood urea nitrogen (BUN) (P < 0.05). Q11 significantly suppressed the expression of NLRP3 in tissues after LPS injection; in vitro studies revealed that activation of NLRP3 signaling and increase of ROS was attenuated by Q11 in LPS-stimulated macrophages, which was reflected by reduced expression of caspase-1 and formation of ASC specks. Overall, our results indicate that Q11 improves the survival of mice with LPS-induced sepsis and attenuates sepsis-induced multiple-organ injury, suggesting that CYP2E1 could be a therapeutic target for sepsis.

Effects of Gene Polymorphisms, Metabolic Activity, and Content of Alcohol Dehydrogenase and Acetaldehyde Dehydrogenases on Prognosis of Hepatocellular Carcinoma Patients.

BACKGROUND: Alcohol dehydrogenase and acetaldehyde dehydrogenases have been associated with hepatocellular carcinoma, but how alcohol dehydrogenase and acetaldehyde dehydrogenases alter the prognosis of hepatocellular carcinoma have not been completely elucidated. METHODS: Metabolic activities, gene polymorphisms, and content of alcohol dehydrogenase and acetaldehyde dehydrogenases were determined in 68 fibrotic livers from hepatocellular carcinoma patients. These characteristics were then correlated with clinical features and prognosis in these patients. RESULTS: The median survival time of the ALDH-high activity group (727 days) was increased by 128% compared with that of ALDH-low activity group (319 days), and there was a significant negative correlation between the activity of acetaldehyde dehydrogenases and the level of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. There was no difference in survival time between ALDH2-high and ALDH2-low expression group, though the activity of acetaldehyde dehydrogenases had correlation with the content of ALDH2 (r = 0.6887, P < .001). Mutation at ALDH2rs671 significantly decreased both the activity and content of acetalde- hyde dehydrogenases, but the polymorphism had no relationship with progression of hepatocellular carcinoma patients. In addition, the activity and 3 polymorphisms of alcohol dehydrogenase had no effect on overall survival. Mutation at ADH1Crs698 significantly decreased both the activity and content of alcohol dehydrogenase (P < .05), mutation at ADH1C rs2241894 had an inverse effect, and mutation at ADH1B rs1229984 increased activity but did not affect content. The activity of alcohol dehydrogenase had a moderate cor- relation with the content of ADH1A and ADH1C in livers (P < .05). CONCLUSION: Low activity of acetaldehyde dehydrogenases in livers correlates with poor prognosis and clinical progression in hepatocel- lular carcinoma patients, and both gene polymorphisms and content influence its metabolic activity.