This Article Full Text Full Text (PDF) Data Supplement All Versions of this Article: 26/8/1791    most recent 01.ATV.0000228824.01604.63v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Helske, S. Articles by Kovanen, P. T. Search for Related Content PubMed PubMed Citation Articles by Helske, S. Articles by Kovanen, P. T. Related Collections Pathophysiology Valvular heart disease Other Vascular biology

(Arteriosclerosis, Thrombosis, and Vascular Biology. 2006;26:1791.)
© 2006 American Heart Association, Inc.

Vascular Biology

Increased Expression of Elastolytic Cathepsins S, K, and V and Their Inhibitor Cystatin C in Stenotic Aortic Valves

Satu Helske; Suvi Syväranta; Ken A. Lindstedt; Jani Lappalainen; Katariina Öörni; Mikko I. Mäyränpää; Jyri Lommi; Heikki Turto; Kalervo Werkkala; Markku Kupari; Petri T. Kovanen

From the Wihuri Research Institute (S.H., S.S., K.A.L., J.L., K.O., M.I.M., P.T.K.), Helsinki, Finland; and Division of Cardiology, Department of Medicine (J.L., H.T., M.K.) and Division of Cardiothoracic Surgery, Department of Surgery (K.W.), Helsinki University Central Hospital, Helsinki, Finland.

Correspondence to Petri Kovanen, Wihuri Research Institute, Kalliolinnantie 4, FIN-00140 Helsinki, Finland. E-mail petri.kovanen{at}wri.fi

Objective— To investigate the possible role of elastolytic cathepsins S, K, and V and their endogenous inhibitor cystatin C in adverse extracellular matrix remodeling of stenotic aortic valves.

Methods and Results— Stenotic aortic valves were collected at valve replacement surgery and control valves at cardiac transplantations. The expression of cathepsins S, K, and V and cystatin C was studied by conventional and real-time polymerase chain reaction and by immunohistochemistry. Total cathepsin activity in the aortic valves was quantified by a fluorometric microassay. When compared with control valves, stenotic valves showed increased mRNA expression of cathepsins S, K, and V (P<0.05 for each) and a higher total cathepsin activity (P<0.001). In stenotic valves, cystatin C mRNA was increased (P<0.05), and cystatin C protein was found particularly in areas with infiltrates of inflammatory cells. Both cathepsin S and cystatin C were present in bony areas of the valves, whereas cathepsin V localized to endothelial cells in areas rich of neovascularization. Incubation of thin sections of aortic valves with cathepsins S, K, and V resulted in severe disruption of elastin fibers, and this cathepsin effect could be blocked by adding cystatin C to the incubation system.

Conclusions— Stenotic aortic valves show increased expression and activity of elastolytic cathepsins S, K, and V. These cathepsins may accelerate the destruction of aortic valvular extracellular matrix, so promoting the progression of aortic stenosis.

Here, we demonstrate increased expression and activity of the elastolytic cathepsins S, K, and V and their endogenous inhibitor cystatin C in stenotic aortic valves. These findings suggest that these cathepsins may participate in the adverse remodeling of the valves and accelerate the progression of aortic stenosis.

Key Words: aortic stenosis • cathepsin • cystatin C • elastin • heart valves

This article has been cited by other articles:

				M. Novinec, R. N. Grass, W. J. Stark, V. Turk, A. Baici, and B. Lenarcic Interaction between Human Cathepsins K, L, and S and Elastins: MECHANISM OF ELASTINOLYSIS AND INHIBITION BY MACROMOLECULAR INHIBITORS J. Biol. Chem., March 16, 2007; 282(11): 7893 - 7902. [Abstract] [Full Text] [PDF]