Masimirembwa C M, Beke M, Hasler J A, Tang B K, Kalow W
Department of Biochemistry, University of Zimbabwe, Harare.
Clin Pharmacol Ther. 1995 Jan;57(1):25-31. doi: 10.1016/0009-9236(95)90262-7.
Caffeine is increasingly used as a biochemical probe for liver function, in cancer epidemiology, and in pharmacogenetics, with its recognized ability to assess the activities of CYP1A2, xanthine oxidase, and N-acetyltransferase-2. The activity of these hepatic enzymes was tested in 45 Shona children from a rural area of Zimbabwe with use of caffeine as a probe. Many of these rural black children had lower indexes of CYP1A2 activity than otherwise on our extensive records; the average value (3.78 +/- 2.9) was significantly (p < 0.001) lower than that of healthy white urban children from Zimbabwe (8.86 +/- 3.36) or from Canada (7.92 +/- 1.88), or that of healthy Canadian adults (5.96 +/- 2.4). A higher CYP1A2 activity in children than in adults is usual. The low CYP1A2 activity of the children from rural Zimbabwe calls for medical studies and suggests a widespread and perhaps serious impairment of certain liver functions. Causes could be parasitic infections with Schistosoma mansoni, causing schistosomiasis, which are endemic, in addition to generally poor nutrition and frequent iodine deficiency. By contrast, the xanthine oxidase activity in rural Shona children was slightly higher than that reported for a healthy Canadian adult population. The N-acetyltransferase activities were comparable in both the rural and urban children and were also similar to those reported in a population study of healthy adult Canadians.
咖啡因越来越多地被用作肝功能、癌症流行病学和药物遗传学方面的生化探针，因其具有评估细胞色素P450 1A2（CYP1A2）、黄嘌呤氧化酶和N - 乙酰转移酶 - 2活性的公认能力。在津巴布韦农村地区的45名绍纳族儿童中，以咖啡因作为探针测试了这些肝脏酶的活性。在我们广泛的记录中，许多这些农村黑人儿童的CYP1A2活性指标低于其他情况；其平均值（3.78±2.9）显著低于（p < 0.001）来自津巴布韦城市的健康白人儿童（8.86±3.36）、来自加拿大的健康白人儿童（7.92±1.88）或加拿大健康成年人（5.96±2.4）。儿童的CYP1A2活性高于成年人是常见的。津巴布韦农村儿童CYP1A2活性低需要进行医学研究，并表明某些肝功能存在广泛且可能严重的损害。原因可能是曼氏血吸虫的寄生虫感染导致血吸虫病，这种病在当地流行，此外还有普遍的营养不良和频繁的碘缺乏。相比之下，绍纳族农村儿童的黄嘌呤氧化酶活性略高于报道的加拿大健康成年人群。农村和城市儿童的N - 乙酰转移酶活性相当，也与加拿大健康成年人的人群研究报告相似。
