Changes in Hsp90 expression determine the effects of cyclosporine A on the NO pathway in rat myocardium

FEBS Letters

Rodella, Luigi¹  Bianchi, Rossella¹  Dessy, Chantal²  Rezzani, Rita¹  Daneau, Géraldine²  Feron, Olivier² 

[1] Division of Human Anatomy, Department of Biomedical Sciences and Biotechnology, University of Brescia, Brescia, Italy;Unit of Pharmacology and Therapeutics (UCL-FATH 5349), University of Louvain Medical School, 53 Avenue E. Mounier, Brussels, Belgium

关键词: Cyclosporine;    Nitric oxide;    Akt;    Hsp90;    Calcineurin;   

DOI  :  10.1016/S0014-5793(03)00898-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Cyclosporine A (CsA) is associated with the development of cardiovascular toxicity in transplant patients but can exert myocardial protection against ischemia/reperfusion damages. We examined in a rat model of chronic CsA administration whether subtle variations in the NO pathway could account for these opposite effects. CsA treatment rapidly led to an increase in myocardial Hsp90 expression promoting the recruitment of Akt and calcineurin, thereby promoting eNOS activation through Ser1177 phosphorylation and Thr495 dephosphorylation, respectively. This was associated with an increase in myocardial VEGF expression and led to anti-apoptotic effects in isolated cardiac myocytes. Upon longer CsA exposure, cardiac toxicity developed, as documented by the infiltration of connective tissue and the increase in iNOS expression. These later effects were associated with a dramatic decrease in the abundance and scaffold function of Hsp90, thereby unraveling the key role of Hsp90 in governing CsA effects.

【 授权许可】

Unknown