Kukongviriyapan Upa, Luangaram Saowanee, Leekhaosoong Krissadarut, Kukongviriyapan Veerapol, Preeprame Srisomporn
Department of Physiology, Faculty of Medicine, Khon Kaen University, Thailand.
Biol Pharm Bull. 2007 Apr;30(4):661-6. doi: 10.1248/bpb.30.661.
Phytochemicals contained in dietary plants provide a variety of health benefits and may reduce the risk of cardiovascular diseases. The aqueous extracts from three popular Thai dietary and herbal plants, Cratoxylum formosum, Syzygium gratum, and Limnophila aromatica, were investigated for the antioxidant and vascular protective activities in the in vitro and in vivo models. The free radical scavenging and antioxidant activities of plant extracts were evaluated in vitro by the 1,1-diphenyl-2-picrylhydrazyl assay, the ferric reducing antioxidant power assay, the intracellular antioxidant activity in rat peritoneal macrophages by dihydrofluorescein assay, and the inhibition of nitric oxide (NO) production in RAW 264.7 macrophages. In an animal model of oxidative stress and vascular dysfunction, male Sprague-Dawley rats were orally administered with aqueous plant extracts (1 g/kg/d) or N-acetylcysteine (NAC; 300 mg/kg/d) as a control for 6 d. On day four, all animals except the normal control group, were administered with phenylhydrazine (PHZ) intraperitoneally. It was demonstrated that the plant extracts possessed high free radical scavenging and antioxidant activities. PHZ induced severe hemolysis and hemodynamic disturbances and treatment with the extracts and NAC significantly improved the hemodynamic status. Vascular responsiveness to bradykinin, acetylcholine, and phenylephrine in PHZ-control rats was markedly impaired, and the plant extracts or NAC largely restored the vascular responses. Moreover, the plant extracts prevented loss of blood reduced glutathione and suppressed formation of plasma malondialdehyde, plasma NO metabolites and blood superoxide anion. It was concluded that the plant extracts possess antioxidants and have potential roles in protection of vascular dysfunction.
食用植物中含有的植物化学物质具有多种健康益处，可能会降低心血管疾病的风险。对三种常见的泰国食用和草药植物——台湾黄牛木、锡兰蒲桃和芳香水蓑衣的水提取物，在体外和体内模型中进行了抗氧化和血管保护活性研究。通过1,1-二苯基-2-苦基肼测定法、铁还原抗氧化能力测定法、用二氢荧光素测定法评估大鼠腹腔巨噬细胞内抗氧化活性以及抑制RAW 264.7巨噬细胞中一氧化氮（NO）的产生，在体外评估了植物提取物的自由基清除和抗氧化活性。在氧化应激和血管功能障碍的动物模型中，雄性斯普拉格-道利大鼠口服植物水提取物（1克/千克/天）或N-乙酰半胱氨酸（NAC；300毫克/千克/天）作为对照，持续6天。在第4天，除正常对照组外，所有动物腹腔注射苯肼（PHZ）。结果表明，植物提取物具有较高的自由基清除和抗氧化活性。PHZ诱导严重溶血和血流动力学紊乱，提取物和NAC治疗显著改善了血流动力学状态。PHZ处理的大鼠对缓激肽、乙酰胆碱和去氧肾上腺素的血管反应明显受损，植物提取物或NAC在很大程度上恢复了血管反应。此外，植物提取物可防止血液中还原型谷胱甘肽的流失，并抑制血浆丙二醛、血浆NO代谢产物和血液超氧阴离子的形成。得出的结论是，植物提取物具有抗氧化剂作用，在保护血管功能障碍方面具有潜在作用。
