三黃瀉心湯 (San-Huang-Xie-Xin-Tang ; SHXT) 為中國傳統之藥物,其主成分為黃芩、黃蓮、大黃。三黃瀉心湯因其主要成份黃芩所含之 Polyphenols compounds 與大黃所含之 Anthraquinone derivates和黃連所含之 alkaloid compounds 具有自由基清除、抗發炎等作用,故本研究將探討三黃瀉心湯是否可改善內毒素脂多醣體 (Lipopolysaccharides, LPS) 所造成的發炎反應以及對大鼠引起之低血壓及細胞激素釋放之作用。於大鼠之巨噬細胞株 RAW 264.7,LPS (0.1?g/mL)會增加inducible-nitric oxide synthases (iNOS)、cyclooxygenase-2 (COX-2) 及 heme oxygenase (HO) 的表現。蛋白質分析 (Western blotting) 結果顯示三黃瀉心湯 (20 ?g、40 ?g、60 ?g、80 ?g、100??g 及 200 ?g) 可以劑量相關性的抑制 LPS 處理 6小時和 15小時後引起的 iNOS 表現及 LPS 處理15小時後 COX-2 的表現。另外,三黃瀉心湯 (20 ?g、40 ?g、60 ?g、80 ?g 及 100??g) 可以劑量相關性增加 LPS 處理 15小時後 HO-1 的表現。在活體實驗中,由靜脈注射 LPS (10 mg/kg) 於 pentobarbital 麻醉之正常血壓的 Wistar 系大鼠,可引起血壓下降及心跳增加的反應。經靜脈注射三黃瀉心湯 ( 0.3 g/kg ) 30 分鐘後,再投予 LPS (10 mg/kg),可抑制LPS引起的低血壓作用並且可以引起劑量相關之心跳增加及持續性血壓增加反應。另利用酵素免疫法分析老鼠血液中 PGE2、IL-1β、IL-6、TNF-α 之含量,結果顯示,三黃瀉心湯 (0.1 及 0.3 g/kg) 呈現劑量相關性減少 LPS 引起 PGE2、IL-1β、IL-6及TNF-α 之釋放,因此,三黃瀉心湯亦可降低由 LPS 引起相關之發炎反應。基於以上結果,顯示三黃瀉心湯具有抗 LPS 引起之低血壓及發炎作用,其作用機轉包括抑制 iNOS 及 COX-2 之表現並增加 HO-1 的表現,以及抑制細胞激素及 PGE2 的產生,進而具有抗發炎及免疫調節的作用。以上結果可作為未來中西醫整合治療敗血症之參考依據。
San-Huang-Xie-Xin-Tang (SHXT) is a traditional Chinese medicinal formula containing Huang Qui, Huanglian and Dauhuang. Polyphenolic compounds isolated from Huang Qui, anthraquinones derivates isolated from Dauhuang and alkaloid compounds isolated from Huanglian have been shown to exhibit free radical scavenging, anti-inflammatory activities. Endotoxin (LPS)-induced activation of inducible NO synthase (iNOS) has been recognized to increase cytokines, NO and subsequent free radical production, which of them play the predominant roles in sepsis. Pharmacological agents with inducible NO synthase (iNOS) inhibition activity are theoretically considered to be reasonable to inhibit NO production and associated septic shock. In this study, we examined the effects of SHXT on LPS-induced hypotension and associated expression of iNOS, cyclooxygenase-2 (COX-2) protein and heme oxygenase (HO-1) on macrophages. In RAW 264.7 cells, LPS-induced expressions of iNOS and COX-2 were inhibited by pretreatment with SHXT in a dose dependent manner. However, SHXT increased the HO-1 expression in LPS-treated cells. Additionally, SHXT also significantly decreased LPS induced cytokines (IL-1, IL-6, TNF-?, IFN-?) in RAW 264.7 cells. Administrations of LPS decreased the mean arterial pressure and a concomitant increase in heart rate in normotensive rats. However, intravenous infusion of SHXT decreased cytokines (IL-1β, IL-6, TNF-?, IFN-?) and PGE2 plasma level and caused a sustained increase in mean arterial pressure and the maintenance of blood pressure for 3~5 hours. In conclusion, SHXT dose-dependently prevented LPS-induced hypotension, which might be mediated through its inhibition activities on cytokines immunoreactivity and the expression of iNOS and COX-2. On the other hand, SHXT increases the HO-1 expression. Therefore, SHXT may be useful in the prevention and treatment of endotoxin induced hypotension.