Attenuation of endoplasmic reticulum stress using the chemical chaperone 4-phenylbutyric acid prevents cardiac fibrosis induced by isoproterenol

作者：Ayala Pedro; Montenegro Jose; Vivar Raul; Letelier Alan; Aranguiz Urroz Pablo; Copaja Miguel; Pivet Deisy; Humeres Claudio; Troncoso Rodrigo; Miguel Vicencio Jose; Lavandero Sergio; Diaz Araya Guillermo^*

来源：Experimental and Molecular Pathology, 2012, 92(1): 97-104.

DOI：10.1016/j.yexmp.2011.10.012

• 4-Phenylbutyric acid
• Endoplasmic reticulum stress
• Heart
• Isoproterenol
• Fibrosis

Increasing evidence indicates that endoplasmic reticulum (ER) stress is involved in various diseases. In the human heart, ischemia/reperfusion has been correlated to ER stress, and several markers of the unfolded protein response (UPR) participate during cardiac remodeling and fibrosis. Here, we used isoproterenol (ISO) injection as a model for in vivo cardiac fibrosis. ISO induced significant cardiomyocyte loss and collagen deposition in the damaged areas of the endocardium. These responses were accompanied by an increase in the protein levels of the lumina! ER chaperones RIP and PDI, as well as an increase in the UPR effector CHOP. The use of the chemical chaperone 4-phenylbutyric acid (4-PBA) prevented the activation of the UPR, the increase in luminal chaperones and also, leads to decreased collagen deposition, cardiomyocyte loss into the damaged zones. Our results suggest that cardiac damage and fibrosis induced in vivo by the beta-adrenergic agonist ISO are tightly related to ER stress signaling pathways, and that increasing the ER luminal folding capacity with exogenously administrated 4-PBA is a powerful strategy for preventing the development of cardiac fibrosis. Additionally, 4-PBA might prevent the loss of cardiomyocytes. Our data suggests that the attenuation of ER stress pathways with pharmacological compounds such as the chemical chaperone 4-PBA can prevent the development of cardiac fibrosis and adverse remodeling.

• 出版日期2012-2