Xu Kedi1, Yan Ming, Wang Yongping, Yang Yi, Zheng Xiaoxiang. 1. Dept of Biomedical Engineering, Zhejiang University, Key Laboratory of Biomedical Engineering of Ministry of Education, Zheda Road 38, Hangzhou, 310027, Zhejiang, China.
Abstract
OBJECTIVE: Smooth muscle cells (SMCs) death promotes atherosclerotic lesion necrosis and plaque destabilization. We investigated the potential mechanisms of rat SMCs death in response to excess free cholesterol (FC). METHODS AND RESULTS: Rat aortic SMCs were incubated with "water soluble cholesterol" and acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor Sandoz58035 to establish FC-overloading cell model. Disruption of mitochondrial network and endoplasmic reticulum (ER) was observed after 12h incubation by transient transfection. After treated for 24h, enhanced cell death was noted as detected by propidium iodide (PI) staining/flow cytometry (P<0.001 vs. control). SMCs death was associated with markedly decreased mitochondrial transmembrane potential (Deltaphim), as well as upregulation of cellular reactive oxygen species (ROS) and ER stress. We also investigated possible signaling pathways involved in excess FC-initiated cell death and found that unfolded protein response (UPR) was activated, with increased cellular Bax expression and release of mitochondrial cytochrome c. CONCLUSION: Our findings suggested that FC-overloading might trigger SMCs death. Both ER- and mitochondria-based signals might be implicated in these lethal events.
OBJECTIVE: Smooth muscle cells (SMCs) death promotes atherosclerotic lesion necrosis and plaque destabilization. We investigated the potential mechanisms of rat SMCs death in response to excess free cholesterol (FC). METHODS AND RESULTS:Rat aortic SMCs were incubated with "water soluble cholesterol" and acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor Sandoz58035 to establish FC-overloading cell model. Disruption of mitochondrial network and endoplasmic reticulum (ER) was observed after 12h incubation by transient transfection. After treated for 24h, enhanced cell death was noted as detected by propidium iodide (PI) staining/flow cytometry (P<0.001 vs. control). SMCs death was associated with markedly decreased mitochondrial transmembrane potential (Deltaphim), as well as upregulation of cellular reactive oxygen species (ROS) and ER stress. We also investigated possible signaling pathways involved in excess FC-initiated cell death and found that unfolded protein response (UPR) was activated, with increased cellular Bax expression and release of mitochondrial cytochrome c. CONCLUSION: Our findings suggested that FC-overloading might trigger SMCs death. Both ER- and mitochondria-based signals might be implicated in these lethal events.
Authors: Ayce Yesilaltay; Gregoriy A Dokshin; Dolores Busso; Li Wang; Dalia Galiani; Tony Chavarria; Eliza Vasile; Linda Quilaqueo; Juan Andrés Orellana; Dalia Walzer; Ruth Shalgi; Nava Dekel; David F Albertini; Attilio Rigotti; David C Page; Monty Krieger Journal: Proc Natl Acad Sci U S A Date: 2014-11-03 Impact factor: 11.205
Authors: R Bravo-Sagua; A E Rodriguez; J Kuzmicic; T Gutierrez; C Lopez-Crisosto; C Quiroga; J Díaz-Elizondo; M Chiong; T G Gillette; B A Rothermel; S Lavandero Journal: Curr Mol Med Date: 2013-02 Impact factor: 2.222