Expression of angiotensin-converting enzyme 2 in CCL4-induced rat liver fibrosis.
The renin angiotensin system (RAS) plays a major role in liver fibrosis. A novel homologue of angiotensin converting enzyme, ACE2, was identified as a negative regulator of RAS as it degrades Ang II to Ang1-7. We investigated in vivo the expression of ACE2 in liver fibrosis. We evaluated the relationship between biochemical variables and liver tissue expression of ACE2, the correlation between a histological assessment of liver fibrosis and liver tissue expression of ACE2. Male SD rats were randomly divided into a CCL4 group which received injections of CCL4 and the control group which received injections of olive oil. Liver pathology was examined by H&E and Sirius red staining, and real-time PCR was performed to determine the gene expression levels of ACE2 and ACE. Real-time PCR analysis revealed that ACE2 mRNA was higher at the two-, four-, and six-week time points, respectively (p<0.01). Similarly, hepatic ACE mRNA was significantly increased after CCL4 injection. There was a significant correlation between ACE and ACE2 gene expression (r=0.750, P<0.001). ACE2 gene expression strongly correlated with ALT (r=0.669, P<0.0001) and AST levels (r=0.815, P<0.0001). There was a significant correlation between circulating ACE2 and histological scores of liver fibrosis. ACE2 and ACE gene expression correlated with the ISHAK score (r=0.850, P<0.001; r=0.806, P<0.001). There was a significant relationship between ACE2 gene expression and the degree of liver fibrosis. ACE2 plays a crucial role in liver fibrogenesis.
Huang
Qian
Q
Department of Infectious Disease, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, People's Republic of China.
Xie
Qing
Q
Shi
Cui-Cui
CC
Xiang
Xiao-Gang
XG
Lin
Lan-Yi
LY
Gong
Bang-Dong
BD
Zhao
Gang-De
GD
Wang
Hui
H
Jia
Ni-Na
NN
D000085962:Angiotensin-Converting Enzyme 2; D000818:Animals; D015153:Blotting, Western; D002251:Carbon Tetrachloride / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D008103:Liver Cirrhosis / Q000139:chemically induced / Q000235:genetics / Q000378:metabolism*; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000235:genetics / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D002251:Carbon Tetrachloride; D007703:Peptidyl-Dipeptidase A; C000705329:Ace2 protein, rat; D000085962:Angiotensin-Converting Enzyme 2