Publication
Total Flavones ofRhododendron simsiiPlanch Flower Protect against Cerebral Ischemia-Reperfusion Injury via the Mechanism of Cystathionine-γ-Lyase-Produced H2S
Publisher:
Hindawi Limited
Date:
31-05-2018
DOI:
10.1155/2018/8903849
Abstract: Total flavones of Rhododendron simsii Planch flower (TFR) have a significant protective effect against cerebral ischemia-reperfusion injury. However, its mechanism is unclear. This study investigated the protection of TFR against cerebral ischemia-reperfusion injury via cystathionine- γ -lyase- (CSE-) produced H 2 S mechanism. CSE -/- mice and CSE-siRNA-transfected rat were used. Relaxation of cerebral basilar artery (CBA), H 2 S, and CSE mRNA were measured. TFR significantly inhibited cerebral ischemia-reperfusion-induced abnormal neurological symptom and cerebral infarct in the normal rats and the CSE +/+ mice, but not in the CSE -/- mice, and the inhibition was markedly attenuated in CSE-siRNA-transfected rat TFR elicited a significant vasorelaxation in rat CBA, and the relaxation was markedly attenuated by removal of endothelium or CSE-siRNA transfection or coapplication of NO synthase inhibitor L-NAME and PGI 2 synthase inhibitor Indo. CSE inhibitor PPG drastically inhibited TFR-evoked vasodilatation resistant to L-NAME and Indo in endothelium-intact rat CBA. TFR significantly increased CSE mRNA expression in rat CBA endothelial cells and H 2 S production in rat endothelium-intact CBA. The increase of H 2 S production resistant to L-NAME and Indo was abolished by PPG. Our data indicate that TFR has a protective effect against the cerebral ischemia-reperfusion injury via CSE-produced H 2 S and endothelial NO and/or PGI 2 to relax the cerebral artery.