Abstract 626: Vascular Endothelial HSP60 and Von Willebrand Factor Induction Are Both Involved in Promoting Fatty-Streak Formation in ApoE Null Mice
Objectives: This study was designed to determine the murine atherosclerosis in ApoE null mice with inducible expression of human heat shock protein 60 (hHSP60) in vascular endothelium.
Background: Autoimmunity to HSP60 may be involved in eliciting early atherosclerotic lesions. Most classical risk factors of atherosclerosis were previously shown in cell culture models to induce HSP60 expression in vascular ECs and in vivo particularly at regions predilected to lesions. However, it has not been demonstrated directly in an animal model whether HSP60 induction in ECs are capable of influencing lesion formation.
Methods: We developed ApoE-/-::Cdh5-CreERT2::G-Lox-HSP60 triple Tg mouse model with tamoxifen-induced hHSP60 expression in ECs. Eight week-old triple TG mice were fed by tamoxifen citrate-contained chow for 2 weeks, followed by high fat chow (HF) for additional 4 and 8 weeks before sacrificed for oil red staining for fatty streaks and IHC staining.
Results: In tamoxifen-fed triple Tg mouse, vascular EC expression of hHSP60 increased fatty-streak formation and increased the severity of lesions in comparison with uninduced triple Tg or wildtype ApoE mouse. In triple Tg mouse, we found tamoxifen strongly induced HSP60 expression in ECs of the lesions and to a lesser degree in ECs of veins and other arterial regions not predilected to lesions. Concomitant VWF induction at ECs and subendothelial regions was observed at areas with increased HSP60 expression.
Conclusions: hHSP60 induction at vascular ECs accelerates fatty-steak formation in ApoE null mice that may involve increasing local VWF expression.
Author Disclosures: T. Chen: None. M. Chen: None. T. Chen: None. S. Liu: None. C. Hsu: None. K.M. Lin: None.
- © 2015 by American Heart Association, Inc.