The Significance Of IL-6,GATA-6 And GATA-6 Methylation In Pulmonary Tissues Of Rats With Pulmonary Arterial Hypertension

Objective:The significance of IL-6,GATA-6 and GATA-6 methylation in pulmonary tissues during the course of pulmonary hypertension was studied by MCT induction in rats.Methods:54 adult male SD rats were randomly divided into the solvent control group（group A,n=18）,the sham operation control group（group B,n=18）,and the MCT group（group C,n=18）.The rats in group C were given 1%MCT by intraperitoneal injection of60mg/kg,the rats in group A were given the same amount of 2:8 anhydrous ethanol normal saline,and the rats in group B were given abdominal puncture only.At the three time points of day 7（T₁）,day 14（T₂）and day 21（T₃）after modeling,separately for each set of 6 rats right ventricular pressure,right ventricular hypertrophy index detection,HE staining of lung tissue to observe pathological changes of lung,immunohistochemical method to detect lung tissue in the expression of GATA-6,IL-6,Real-time PCR detection of lung tissue GATA-6 expression level,Western Blot detection of lung tissue IL-6protein expression levels,methylation PCR detection GATA-6 degree of methylation in the lung tissue.Results:Group C compared with group A and group B in the rat in T_1-3right ventricular average pressure and right ventricular hypertrophy index significantly higher in group C（P<0.05）and average T_1-3-3 right ventricular pressure and right ventricular hypertrophy index increasing change and peaked in T₃（P<0.05）,group A compared with group B right ventricular average pressure and right ventricular hypertrophy index difference had no statistical significance（P>0.05）.Immunohistochemical results of IL-6 showed that the expression of IL-6 in lung tissues of group C was significantly increased at T_1-3-3 compared with that of group A and group B（P<0.05）,and the expression of IL-6 in lung tissues of group C was significantly increased at T₃ and reached the highest level（P<0.05）,while the expression of IL-6 in lung tissues of group A and group B was not statistically significant（P>0.05）.Immunohistochemical results of GATA-6 showed that the expression of GATA-6 in lung tissues of group C was significantly decreased at T_1-3（P<0.05）,and the expression of GATA-6 in lung tissues of group C was significantly decreased at T₃ and reached the lowest peak（P<0.05）,while the expression of GATA-6 in lung tissues of group A and group B was not statistically significant（P>0.05）.Western Blot results showed that the expression of IL-6 in lung tissues of group C was significantly increased in T_1-3-3 compared with group A and group B（P<0.05）,and the expression of IL-6 in lung tissues of group C was significantly increased in T₃ and reached the highest level（P<0.05）.The expression difference of IL-6 in lung tissues of group A and group B was not statistically significant（P>0.05）.Real-time PCR results showed that the expression of GATA-6 in lung tissues of group C was significantly lower than that of group A and group B（P<0.05）;the expression of GATA-6 in lung tissues of group C was significantly lower than that of group T₃ and reached the minimum peak（P<0.05）;the expression of GATA-6in lung tissues of group A and group B was not statistically significant（P>0.05）.GATA-6methylation results showed that compared with group A and group B,GATA-6methylation level in lung tissues of group C was significantly increased at T_1-3（P<0.05）,and the methylation level of GATA-6 in group C was increased and reached the peak at T₃（P<0.05）,while the methylation level of GATA-6 in group A and group B was not statistically significant（P<0.05）.Correlation analysis results showed that there was a significant negative correlation between IL-6 and GATA-6 in group C（r=-0.887,P=0.000）.There was a significant positive correlation between IL-6 and GATA-6methylation in group C（r=0.944,P=0.000）.There was a significant negative correlation between GATA-6 and GATA-6 methylation in group C（r=-0.922,P=0.000）.Conclusion:1.The expression of IL-6 was significantly increased,the expression of GATA-6 was significantly decreased,and the methylation of GATA-6 was significantly increased in pulmonary hypertension rats.2.The relationship between IL-6、GATA-6and methylation of GATA-6 may play a role in the pathogenesis of pulmonary hypertension in rats.3.It was speculated that high methylation of GATA-6 induced by IL-6 might be one of the reasons for the decrease of GATA-6 expression in the formation of pulmonary hypertension in rats...