龍膽瀉肝湯、茵陳蒿湯及WTTC體外抑制氫氧自由基形成和清除氫氧自由基之活性

Prescriptions of Long Dan Xie Gan Tang, Yin Chen Hao Tang and WTTC Inhibit the Formation of Superoxide Radical and Scavenge Superoxide Radical in Vitro

自由基為正常生物體內常見的活性分子。雖然如此，體內過量的產生自由基將會破壞細胞及組織， 最終可引起許多疾病。本次研究的目的為以xanthine/xanthine oxidase 系統和cytochrome C 還原法來探討龍膽瀉肝湯、茵陳蒿湯及WTTC 水抽物之抑制氫氧自由基形成及清除氫氧自由基的活性。結果顯示上述方劑的水抽物皆具抑制氫氧自由基形成及清除氫氧自由基的能力。其中，在抑制氫氧自由基形成方面，其活性強度由強至弱的順序為WTTC 水抽物（IC50 = 4.02 ± 0.49 mg/ml）＞茵陳蒿水抽物（IC50 = 5.86 ± 0.38 mg/ml）＞龍膽瀉肝湯水抽物（IC50 = 6.52 ± 0.38 mg/ml）。在清除氫氧自由基方面，還是以WTTC 水抽物的能力最佳（IC50 = 0.04 ± 0.004 mg/ml），茵陳蒿湯水抽物次之（IC50 = 0.11 ± 0.02 mg/ml），而龍膽瀉肝湯水抽物最弱（IC50 =0.55 ± 0.18 mg/ml）。總的來說，龍膽瀉肝湯、茵陳蒿湯及WTTC 的水抽物具有不同程度的抗氫氧自由基活性。

Free radicals are reactive molecules that occur normally in organisms. However the excess generation of free radical can cause tissues and cells to be damaged, and might result in several diseases. In this study, the anti-superoxide radical formation and the superoxide radical scavenging activities of the water extract of prescriptions, Long Dan Xie Gan Tang (LDXGT), Yin Chen Hao Tang (YCHT) and WTTC, were evaluated by the xanthine/xanthine oxidase system and the cytochrome C reduction method, respectively. Results demonstrated that the water extract of the prescriptions suppressed superoxide anion formation and scavenged the radical in a dose-dependent manner. The potency on inhibiting the generation of superoxide radical was in the order of WTTC water extract (IC50 = 4.02 ± 0.49 mg/ml) > YCHT water extract (IC50 = 5.86 ± 0.38 mg/ml) > LDXGT water extract (IC50 = 6.52 ± 0.38 mg/ml). The strength of superoxide radical scavenging activity was in the order of WTTC water extract (IC50 = 0.04 ± 0.004 mg/ml) > YCHT water extract (IC50 = 0.11 ± 0.02 mg/ml) > LDXGT water extract (IC50 = 0.55 ± 0.18 mg/ml). In summary, the water extract of prescription LDXGT, YCHT and WTTC exhibit anti-superoxide radical activity in different magnitudes of potency in vitro.