Bexarotene Exerts Protective Effects Through Modulation of the Cerebral Vascular Smooth Muscle Cell Phenotypic Transformation by Regulating PPARγ/FLAP/LTB After Subarachnoid Hemorrhage in Rats

• Main Authors: Zhaosi Zhang, Guosheng Zhao, Liu Liu, Junchi He, Rami Darwazeh, Han Liu, Hong Chen, Chao Zhou, Zongduo Guo, Xiaochuan Sun
• Format: Article
• Language: English
• Published: SAGE Publishing 2019-09-01
• Series: Cell Transplantation
• Online Access: https://doi.org/10.1177/0963689719842161
• ISSN: 0963-6897; 1555-3892

Vascular smooth muscle cells (VSMCs) play an important role after a subarachnoid hemorrhage (SAH). The changes in VSMCs following bexarotene treatment after SAH are unknown. In the present study, neurological impairment, decreased cerebral cortical blood flow and transformation of cerebral VSMCs from a contractile to a synthetic phenotype were observed after SAH. Bexarotene reduced neurological impairment, improved cerebral cortical blood flow, inhibited VSMC phenotypic transformation and suppressed the expression of 5-lipoxygenase-activating protein (FLAP) and leukotriene B4 (LTB 4 ), which was partly reversed by GW9662, an inhibitor of peroxisome proliferator-activated receptor gamma (PPARγ). Mechanistically, sh-PPARγ-mediated phenotypic transformation of VSMCs was partially suppressed by MK886, an antagonist of FLAP. Therefore, we conclude that bexarotene reduced neurological impairment, improved cerebral cortical blood flow and inhibited the VSMC phenotypic transformation after SAH, which was achieved by activating PPARγ-mediated inhibition of FLAP/LTB 4 in VSMCs