单位:[1]Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, People’s Republic of China医技科室北京市临床医学研究所实验中心首都医科大学附属北京友谊医院[2]Liver Research Center, Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong’an Road, Xicheng District, Beijing 100050, People’s Republic of China临床科室国家中心肝病分中心首都医科大学附属北京友谊医院[3]Beijing Clinical Medicine Institute, Beijing 100050, People’s Republic of China[4]National Clinical Research Center of Digestive Diseases, Beijing 100050, People’s Republic of China首都医科大学附属北京友谊医院
Background and aims Lysyl oxidase-like-1 (LOXL1), a vital cross-linking enzyme in extracellular matrix (ECM) maintenance, promotes fibrosis via enhancement of ECM stability. However, the potential role of LOXL1 in the pathogenesis of nonalcoholic steatohepatitis (NASH) has not been previously studied. Methods We generated Loxl1(fl/fl) mice to selectively delete LOXL1 in hepatic stellate cells (HSCs) (Loxl1(fl/fl)Gfap(cre); Loxl1(fl/fl) as littermate controls) and then examined liver pathology and metabolic profiles in Loxl1(fl/fl)Gfap(cre) fed with either a choline-deficient L-amino acid-defined (CDAA) diet or an isocaloric control diet for 16 weeks. Thereafter, the findings from the animal model were confirmed in 23 patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD). Results LOXL1 was significantly increased in CDAA induced non-obese NASH compared with the control diet, and LOXL1 deficient in HSCs ameliorated CDAA-induced inflammation and fibrosis, with reduced expression of pro-inflammation and pro-fibrogenic genes in the HSCs-specific LOXL1 knockout mice model. Interestingly, LOXL1 deficient in HSCs could attenuate hepatic steatosis and reverse the metabolic disorder by restoring adipose tissue function without altering the effect of hepatic lipogenesis gene expression in non-obese NASH model. More importantly, analyses of serum LOXL1 and leptin levels from NAFLD patients revealed that LOXL1 was positively correlated with histological fibrosis progression, whereas it was inversely correlated with leptin levels, especially in non-obese NAFLD patients. Conclusion LOXL1 may contribute to fibrosis progression in non-obese NAFLD, and HSCs-specific knockout of LOXL1 attenuated liver steatosis, inflammation, fibrosis, , and improved lipid metabolic abnormalities. Hence, LOXL1 inhibition may serve as a new therapeutic strategy for NASH.
基金:
National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [81970524, 81500456]
第一作者单位:[1]Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, People’s Republic of China[3]Beijing Clinical Medicine Institute, Beijing 100050, People’s Republic of China[4]National Clinical Research Center of Digestive Diseases, Beijing 100050, People’s Republic of China
通讯作者:
通讯机构:[2]Liver Research Center, Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong’an Road, Xicheng District, Beijing 100050, People’s Republic of China[3]Beijing Clinical Medicine Institute, Beijing 100050, People’s Republic of China[4]National Clinical Research Center of Digestive Diseases, Beijing 100050, People’s Republic of China