Changes Of NOX4mRNA And AngⅡ Levels During Hepatic Fibrosis And The Effect Of Benazepril On Them

Objective:To investigate the changes of Ang Ⅱ level and NOX4 m RNA expression in rat liver fibrosis induced by CCl4 and the changes of Ang Ⅱ in plasma of chronic hepatitis B and chronic cirrhosis,and to explore the relationship between Ang Ⅱ and NOX4 and the pathogenesis of liver fibrosis and cirrhosis.To study the effect of benazepril on Ang Ⅱ level and NOX4 m RNA expression in rats with hepatic fibrosis.Objective to explore the role of various indexes in liver fibrosis and the possible mechanism of benazepril in anti-fibrosis,and to provide some new ideas for clinical treatment of anti-hepatic fibrosis.Methods:1.Twenty-two 6-week-old SD male rats were randomly divided into three groups: normal control group(n= 6),model group(n=8)and benazepril group(n=8).In addition to the control group,the other two groups were given subcutaneous injection of 40% CCl4 oil,twice a week,the first dose was 5 ml/kg,and the subsequent injection dose was 2 ml/kg.The control group was subcutaneously injected with the same dose of oil.The prophylaxis group was given benazepril 10 mg kg-1 by gavage from the first day of the experiment,and the other two groups were given the same dose of normal saline until the end of the experiment.Three groups of rats were given a normal diet.At the 8th week,6 rats were killed in normal control group,model group and preventive treatment group.Routine HE and Masson trichrome staining were performed on the liver tissue of the rats in each group,and then the pathological changes of the liver in each group were observed under microscope.The concentration of Ang Ⅱ in liver homogenate of each group was determined by ABC-ELISA method and the expression of NOX4 m RNA in liver tissue was detected by RT-PCR.2.Plasma samples were collected from 20 healthy subjects,20 patients with chronic hepatitis B and 20 patients with chronic liver cirrhosis.The levels of Ang Ⅱ in plasma were measured by ELISA method.Results:(1)Pathological features of liver tissue: The structure of hepatic lobule in normal control group was normal.In the model group,part of the hepatic lobule structure became disordered at the 8th week,and the pseudolobules were formed around the hepatic cells by the fibrous septum.The fibrosis degree of the liver tissue in the treatment group was less than that in the model group.(2)The results of Ang Ⅱ measured by ELISA: the concentration of Ang Ⅱ in liver homogenate of the model group(48.625 ±1.357 ng/ml)was significantly higher than that in the control group(23.330±1.606 ng/ml)(P<0.05),and the concentration of Ang Ⅱ in the treatment group was 45.518 ±3.072 ng / ml lower than that in the model group(48.625 ±1.357 ng/ml)(P<0.05).(3)The expression of NOX4 m RNA in the model group was significantly higher than that in the control group(2.03±0.31)(P<0.05),and the expression of NOX4 m RNA in the treatment group was 15.93±5.01)significantly lower than that in the model group(31.78±3.96)(P<0.05).(4)Spearman correlation analysis showed that there was a significant positive correlation between the concentration of Ang Ⅱ in liver homogenate and the expression of NOX4 m RNA in liver tissue of the three groups(r=0.472,P<0.05).(5)Plasma Ang Ⅱ levels in patients with chronic hepatitis B(59.98±12.97 pg/ml)and chronic liver cirrhosis(90.81±28.45 pg/ml)were significantly higher than those in normal controls(21.53±18.27 pg/ml),the difference was statistically significant(P<0.05);The level of plasma Ang Ⅱ in patients with chronic liver cirrhosis(90.81±28.45 pg/ml)was significantly higher than that in patients with chronic hepatitis B(59.98±12.97 pg/ml),and the difference was statistically significant(P<0.05).Conclusions:(1)With the formation of hepatic fibrosis,the level of Ang Ⅱ and the expression of NOX4 m RNA in liver tissue increased.The level of Ang Ⅱ in patients with chronic hepatitis B and chronic liver cirrhosis was higher than that in healthy controls.These results suggest that the occurrence and development of hepatic fibrosis may be related to Ang Ⅱ and NOX4.(2)There was a positive correlation between the expression of NOX4 m RNA and the level of Ang Ⅱ in the process of hepatic fibrosis.(3)It is further confirmed that Benazepril has anti-hepatic fibrosis effect,which may be achieved by inhibiting the level of Ang Ⅱ and further inhibiting the oxidative stress induced by NOX4.