Karori S M, Ngure R M, Wachira F N, Wanyoko J K, Mwangi J N
Department of Biochemistry and Molecular Biology, Egerton University, PO Box 536, Egerton, Kenya.
Parasitol Int. 2008 Sep;57(3):325-33. doi: 10.1016/j.parint.2008.02.003. Epub 2008 Feb 26.
An in vivo study was carried out to determine the effect of different types of Kenyan tea extracts on male Swiss albino mice infected with Trypanosoma brucei brucei isolate KETRI 2710. The isolate produced a similar clinical picture after a pre-patent period of 5 days post-infection (DPI). Parasitemia levels in the untreated mice and those given different teas developed exponentially at similar rates reaching similar densities at the peak of parasitemia 8 DPI. Between 9 and 13 DPI parasitemia decreased more rapidly in tea treated compared to the untreated mice which indicated that tea lowered parasitemia level. Anaemia indicated by a fall in erythrocyte packed cell volume (PCV) occurred within 4 DPI and remained below the normal levels until the terminal stages of the disease. A significant difference (P<0.05) was observed 11 DPI between the tea treated and the untreated mice indicating that tea enhanced resistance to erythrocyte destruction. Mice treated with tea exhibited significantly (P<0.01) reduced parasite-induced hypoalbuminemia as compared to the untreated. Since albumin is a negative acute phase protein, it shows a decrease during inflammatory conditions and therefore its elevation in the mice given tea in this study clearly demonstrated that tea ameliorated inflammation induced by T. b. brucei. Although green and white teas were superior in most of these characteristics, black tea, which is the principle tea product from Kenya, displayed remarkable properties some even comparable to those of green tea. Interestingly, tea was more efficacious than dexamethasone an established anti-inflammatory drug, demonstrating its therapeutic potential.
开展了一项体内研究,以确定不同类型的肯尼亚茶提取物对感染布氏布氏锥虫分离株KETRI 2710的雄性瑞士白化小鼠的影响。该分离株在感染后5天的潜伏期后产生了相似的临床症状。未治疗小鼠和给予不同茶叶的小鼠的寄生虫血症水平以相似的速率呈指数增长,在感染后8天寄生虫血症达到峰值时密度相似。在感染后9至13天,与未治疗的小鼠相比,接受茶治疗的小鼠的寄生虫血症下降得更快,这表明茶降低了寄生虫血症水平。红细胞压积(PCV)下降表明的贫血在感染后4天内出现,并一直低于正常水平,直到疾病末期。在感染后11天,观察到茶治疗组和未治疗组小鼠之间存在显著差异(P<0.05),这表明茶增强了对红细胞破坏的抵抗力。与未治疗的小鼠相比,用茶治疗的小鼠寄生虫诱导的低白蛋白血症显著降低(P<0.01)。由于白蛋白是一种负急性期蛋白,在炎症状态下会减少,因此在本研究中给予茶的小鼠中其升高清楚地表明茶减轻了布氏布氏锥虫诱导的炎症。尽管绿茶和白茶在这些特性中的大多数方面更具优势,但作为肯尼亚主要茶叶产品的红茶也表现出显著特性,有些甚至与绿茶相当。有趣的是,茶比已确立的抗炎药物地塞米松更有效,证明了其治疗潜力。