黃芩 ? 對肺癌細胞株 H441 之界面活性劑蛋白質 A 基因表現的影響

1. 黃芩?對肺癌細胞株H441之界面活性劑蛋白質A基因表現的影響黃芩?對肺癌細胞株H441之界面活性劑蛋白質A基因表現的影響 • 面活性劑蛋白質A是肺部界面活性劑含量最豐富的一種界面活性劑蛋白質，主要是由第二型肺泡細胞所分泌，含量約總界面活性劑蛋白質的百分之五十，可降低肺泡的表面張力以利於氣體的交換是肺泡產生功能的重要因子。臨床上，呼吸窘迫症候群是早產兒發生的主要症狀。該現象的發生乃因界面活性劑分泌不足之緣故。而現今臨床用藥之醣質性皮質類固醇及外生性界面活性劑，均會造成早產兒日後腦部生長及發育上不成熟及病變等副作用。本研究選用中草藥中，具安胎作用之黃芩生藥主成分之一的黃芩苷(Baicalin)為測試的藥物，對肺癌細胞株H441之界面活性劑蛋白質A進行時間性及劑量性分析的體外試驗。由反轉錄-聚合脢連鎖反應及西方墨點法分析的結果顯示，界面活性劑蛋白質A的表現量確實能隨著黃芩苷處理的時間及劑量的增加而增加，在150 nM的黃芩苷處理48小時時，達最高的表現量。在互補去氧核醣核酸減除法的分析結果可得知，黃芩苷是藉由增加細胞色素C氧化酶及類導換素促進蛋白的表現量來提高腺核苷三磷酸的形成，使得蛋白質磷酸化作用旺盛，終至界面活性劑蛋白質A從第二型肺泡細胞的分泌增加，或藉由調控轉錄機制來增加界面活性劑蛋白質A基因的表現量。

2. Effects of Baicalin on the gene expression of surfactant protein A (SP-A) in lung adenocarcinoma cell line H441 • Surfactant protein A (SP-A) is the most abundant surfactant protein component of pulmonary surfactant, constituting about 50% of the total surfactant protein. SP-A is a material secreted by the alveolar type II cell that reduces surface tension at the alveolar air-liquid interface. It is an important role on the function of the alveolus.Respiratory Distress Syndrome (RDS) is major cause of morbidity in preterm neonates, which results from a deficiency of pulmonary surfactant. Maternal glucocorticoid (ex: Dexamethasone) and exogenous surfactant (ex: Surrata and Exosurf) therapy decreased the incidence of death and RDS, but the treatments glucocorticoid and exogenous surfactant have an adverse effect on the brain development of the premature infant.Analysis of SP-A gene expression using RT-PCR, cDNA subtraction, Western Blotting and 2D in this study. The result of H441 cell culture assayed with RT-PCR and Western blot showed that the gene expression of SP-A was increased when treating with Baicalin (one of the major components of Scutellariae Radix) in time and dosage model. The maximal gene expression of SP-A is exhibited at 150 nM baicalin treated for 48 hours when cDNA subtraction analysis performed. The result shown that treated with baicalin increased copper-zinc superoxide dismutase and cytochrome C oxidase expression and transducin-like enhancer of split 1, which resulted in the elevation of ATP level in the cell, the SP-A secretion thereby increased consistently.