Aldose reductase induced by hyperosmotic stress mediates cardiomyocyte apoptosis - Differential effects of sorbitol and mannitol

Galvez, AS; Ulloa, JA; Chiong M.; Criollo, A; Eisner V.; Barros, LF; Lavandero S.

Abstract

Cells adapt to hyperosmotic conditions by several mechanisms, including accumulation of sorbitol via induction of the polyol pathway. Failure to adapt to osmotic stress can result in apoptotic cell death. In the present study, we assessed the role of aldose reductase, the key enzyme of the polyol pathway, in cardiac myocyte apoptosis. Hyperosmotic stress, elicited by exposure of cultured rat cardiac myocytes to the nonpermeant solutes sorbitol and mannitol, caused identical cell shrinkage and adaptive hexose uptake stimulation. In contrast, only sorbitol induced the polyol pathway and triggered stress pathways as well as apoptosis-related signaling events. Sorbitol resulted in activation of the extracellular signal-regulated kinase (ERK), p54 c-Jun N-terminal kinase (JNK), and protein kinase B. Furthermore, sorbitol treatment resulting in induction and activation of aldose reductase, decreased expression of the antiapoptotic protein Bcl-xL, increased DNA fragmentation, and glutathione depletion. Apoptosis was attenuated by aldose reductase inhibition with zopolrestat and also by glutathione replenishment with N-acetylcysteine. In conclusion, our data show that hypertonic shrinkage of cardiac myocytes alone is not sufficient to induce cardiac myocyte apoptosis. Hyperosmolarity-induced cell death is sensitive to the nature of the osmolyte and requires induction of aldose reductase as well as a decrease in intracellular glutathione levels.

Más información

Título según WOS: Aldose reductase induced by hyperosmotic stress mediates cardiomyocyte apoptosis - Differential effects of sorbitol and mannitol
Título según SCOPUS: Aldose reductase induced by hyperosmotic stress mediates cardiomyocyte apoptosis. Differential effects of sorbitol and mannitol
Título de la Revista: JOURNAL OF BIOLOGICAL CHEMISTRY
Volumen: 278
Número: 40
Editorial: AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
Fecha de publicación: 2003
Página de inicio: 38484
Página final: 38494
Idioma: English
URL: http://www.jbc.org/cgi/doi/10.1074/jbc.M211824200
DOI:

10.1074/jbc.M211824200

Notas: ISI, SCOPUS