Role of Ca²⁺ in the effects of shear stress and TNF-α on caveolin-1 expression

Issue title: Selected Papers from the First Seminar on “Medical Engineering and Therapy”, 27–28 April 2004, Nancy, France

Article type: Research Article

Authors: Fawzi-Grancher, S. | Sun, R.J.^; | Traoré, Mariama | Stoltz, J.F. | Muller, S.^;

Affiliations: Cell and Tissue Engineering and Mechanics, LEMTA-UMR CNRS 7563, Faculté de Médecine Plateau de Brabois, 54500 Vandoeuvre lès Nancy, France | Research Institute of Clinical Medical Sciences, China–Japan Friendship Hospital, 100029 Beijing, China

Note: [] Present address: Department of Life Sciences, National Natural Science Foundation of China, 100085 Beijing, China.

Note: [] Corresponding author: Dr. Sylvaine Muller, Mécanique et Ingénierie Cellulaire et Tissulaire, UMR CNRS 7563 (LEMTA), Faculté de Medecine – B.P. 184, 54500 Vandoeuvre lès Nancy cedex, France. Tel.: +33 0 3 83 68 34 74; Fax: +33 0 3 83 68 34 59; E-mail: mullers@medecine.uhp-nancy.fr.

Abstract: The aim of this work was to study the influences of Ca2+ (medium free calcium, with BAPTA, with 100 mM Ca2+, 100 mM Ca2++10 μM ionomycin) on the expression of caveolin-1 (structural protein of caveolae) of endothelial cells (ECs) submitted to mechanical forces (shear stress) or biochemical stimulation (TNF-α). We found that shear stress enhanced the caveolin-1 expression. Simultaneously, the caveolin-1 expression is dependant on [Ca2+]i: [Ca2+]free medium+100 μM BAPTA<[Ca2+]free medium<[Ca2+]100 mM<[Ca2+]100 mM+10 μM ionomycin. In contrast, TNF-α induced a decrease of caveolin-1 in the cells, whatever the [Ca2+]i. These results suggest that there could be a synergistic effect between shear stress and Ca2+ on caveolin-1 expression but an inflammatory stimulation (TNF-α) induces a down regulation of caveolin-1 expression.

Keywords: Caveolin-1, Ca[TeX:] $^{2+}$, endothelial cell, TNF-α, shear stress, 3D fluorescence microscopy

Journal: Clinical Hemorheology and Microcirculation, vol. 33, no. 3, pp. 253-261, 2005