Lysosomal cysteine peptidase cathepsin L protects against cardiac hypertrophy through blocking AKT/GSK3beta signaling.
The lysosomal cysteine peptidase cathepsin L (CTSL) is an important lysosomal proteinase involved in a variety of cellular functions including intracellular protein turnover, epidermal homeostasis, and hair development. Deficiency of CTSL in mice results in a progressive dilated cardiomyopathy. In the present study, we tested the hypothesis that cardiac overexpression of human CTSL in the murine heart would protect against cardiac hypertrophy in vivo. The effects of constitutive human CTSL expression on cardiac hypertrophy were investigated using in vitro and in vivo models. Cardiac hypertrophy was produced by aortic banding (AB) in CTSL transgenic mice and control animals. The extent of cardiac hypertrophy was quantitated by two-dimensional and M-mode echocardiography as well as by molecular and pathological analyses of heart samples. Constitutive overexpression of human CTSL in the murine heart attenuated the hypertrophic response, markedly reduced apoptosis, and fibrosis. Cardiac function was also preserved in hearts with increased CTSL levels in response to hypertrophic stimuli. These beneficial effects were associated with attenuation of the Akt/GSK3beta signaling cascade. Our in vitro studies further confirmed that CTSL expression in cardiomyocytes blunts cardiac hypertrophy through blocking of Akt/GSK3beta signaling. The study indicates that CTSL improves cardiac function and inhibits cardiac hypertrophy, inflammation, and fibrosis through blocking Akt/GSK3beta signaling.
Tang
Qizhu
Q
Cardiovascular Research Institute of Wuhan University and Department of Cardiology, Renmin Hospital of Wuhan University, People's Republic of China. qizhu.tang@ymail.com
Cai
Jun
J
Shen
Difei
D
Bian
Zhouyan
Z
Yan
Ling
L
Wang
You-Xin
YX
Lan
Jie
J
Zhuang
Guo-Qing
GQ
Ma
Wen-Zhan
WZ
Wang
Wei
W
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000235:genetics / Q000502:physiology; D009320:Atrial Natriuretic Factor / Q000235:genetics; D015153:Blotting, Western; D006332:Cardiomegaly / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D020169:Caspases / Q000378:metabolism; D056668:Cathepsin L; D002403:Cathepsins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D004452:Echocardiography / Q000379:methods; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism*; D000071679:Glycogen Synthase Kinase 3 beta; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*
D000804:Angiotensin II; D009320:Atrial Natriuretic Factor; C000605506:GSK3B protein, human; D000071679:Glycogen Synthase Kinase 3 beta; C000605507:Gsk3b protein, mouse; C000605508:Gsk3b protein, rat; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3; D002403:Cathepsins; D020169:Caspases; D003546:Cysteine Endopeptidases; C534281:CTSL protein, human; D056668:Cathepsin L; C534278:Ctsl protein, mouse; C534280:Ctsl protein, rat