Guo Jian-You, Huo Hai-Ru, Zhao Bao-Sheng, Liu Hong-Bin, Li Lan-Fang, Ma Yue-Ying, Guo Shu-Ying, Jiang Ting-Liang
Tang Center for Herbal Medicine Research, Institute of Chinese Materia Medica, China Academy of Traditional Chinese Medicine, Beijing 100700, China.
Eur J Pharmacol. 2006 May 10;537(1-3):174-80. doi: 10.1016/j.ejphar.2006.03.002. Epub 2006 Mar 10.
Cinnamaldehyde is a principle compound isolated from Guizhi-Tang, which is a famous traditional Chinese medical formula used to treat influenza, common cold and other pyretic conditions. The aim of the present study was to investigate the effects of cinnamaldehyde on expression and activity of cyclooxygenase (COX) and prostaglandin E(2) (PGE(2)) in rat cerebral microvascular endothelial cells (RCMEC). RCMEC were cultured, and identified by immunohistochemistry for von Willebrand factor in cytoplasm of the cells. Then cells were incubated in M199 medium containing interleukin (IL)-1beta in the presence or absence of cinnamaldehyde. After incubation, the medium was collected and the amount of PGE(2) was measured by enzyme-linked immunosorbent assay (ELISA). The cells were harvested, mRNA expression and activity of COX were analyzed by real-time reverse transcription-polymerase chain reaction (RT-PCR) with SYBR Green dye and ELISA respectively. Positive immunostaining for von Willebrand factor was present diffusely in the cytoplasm of >95% RCMEC. IL-1beta increased the mRNA expression and activity of COX-2, and production of PGE(2) in a dose- and time-dependent manner in RCMEC, while mRNA and activity of COX-1 were not significantly altered. Cinnamaldehyde significantly decreased IL-1beta-induced COX-2 activity and PGE(2) production in a dose-dependent manner, while it showed no inhibitory effect on IL-1beta-induced COX-2 mRNA expression in cultured RCMEC. In conclusion, cinnamaldehyde reduces IL-1beta-induced COX-2 activity, but not IL-1beta-induced COX-2 mRNA expression, and consequently inhibits production of PGE(2) in cultured RCMEC.
肉桂醛是从桂枝汤中分离出的主要化合物，桂枝汤是一种著名的用于治疗流感、普通感冒和其他发热病症的传统中药方剂。本研究的目的是探讨肉桂醛对大鼠脑微血管内皮细胞（RCMEC）中环氧化酶（COX）和前列腺素E2（PGE2）表达及活性的影响。培养RCMEC，并通过免疫组织化学法检测细胞胞质中血管性血友病因子（von Willebrand factor）进行鉴定。然后将细胞在含有白细胞介素（IL）-1β的M199培养基中培养，同时设置有无肉桂醛的条件。培养后，收集培养基，采用酶联免疫吸附测定（ELISA）法检测PGE2的含量。收获细胞，分别采用SYBR Green染料实时逆转录-聚合酶链反应（RT-PCR）和ELISA法分析COX的mRNA表达及活性。超过95%的RCMEC胞质中弥漫性存在血管性血友病因子的阳性免疫染色。IL-1β以剂量和时间依赖性方式增加RCMEC中COX-2的mRNA表达、活性以及PGE2的产生，而COX-1的mRNA和活性未发生显著改变。肉桂醛以剂量依赖性方式显著降低IL-1β诱导的COX-2活性和PGE2产生，而对培养的RCMEC中IL-1β诱导的COX-2 mRNA表达无抑制作用。总之，肉桂醛降低IL-1β诱导的COX-2活性，但不降低IL-1β诱导的COX-2 mRNA表达，从而抑制培养的RCMEC中PGE2的产生。
