Department of Pharmaceutical Chemistry and Pharmacognosy, School of Pharmacy, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
Phytother Res. 2013 Dec;27(12):1805-9. doi: 10.1002/ptr.4948. Epub 2013 Feb 11.
In Ethiopian traditional medicine, the leaves of Otostegia integrifolia Benth. are used for the treatment of several diseases including malaria. In an ongoing search for effective, safe and cheap antimalarial agents from plants, the 80% methanol leaf extract O. integrifolia was tested for its in vivo antimalarial activity, in a 4-day suppressive assay against Plasmodium berghei. Activity-guided fractionation of this extract which showed potent antiplasmodial activity resulted in the isolation of a labdane diterpenoid identified as otostegindiol. Otostegindiol displayed a significant (P < 0.001) antimalarial activity at doses of 25, 50 and 100 mg/kg with chemosuppression values of 50.13, 65.58 and 73.16%, respectively. Acute toxicity studies revealed that the crude extract possesses no toxicity in mice up to a maximum dose of 5000 mg/kg suggesting the relative safety of the plant when administered orally. The results of the present study indicate that otostegindiol is among the antimalarial principles in this medicinal plant, and further support claims for the traditional medicinal use of the plant for the treatment of malaria.
在埃塞俄比亚传统医学中，Ostegia integrifolia Benth 的叶子被用于治疗疟疾等多种疾病。在寻找有效、安全、廉价的植物抗疟药物的过程中，80%甲醇叶提取物 O. integrifolia 被用于 4 天抑制性抗疟实验，以检测其体内抗疟活性。对显示出强烈抗疟活性的这种提取物进行活性导向分离，得到了一种被鉴定为 otostegindiol 的裂环二萜。Otostegindiol 在 25、50 和 100mg/kg 剂量下表现出显著的抗疟活性（P<0.001），化学抑制值分别为 50.13%、65.58%和 73.16%。急性毒性研究表明，粗提取物在高达 5000mg/kg 的剂量下对小鼠没有毒性，这表明该植物口服给药时相对安全。本研究结果表明，otostegindiol 是该药用植物中的抗疟成分之一，进一步支持了该植物用于治疗疟疾的传统药用用途的说法。
