Lin J G, Chung J G, Wu L T, Chen G W, Chang H L, Wang T F
Institute of Chinese Medical Science, China Medical College, Taichung, Taiwan.
Am J Chin Med. 1999;27(2):265-75. doi: 10.1142/S0192415X99000306.
Berberine was used to determine loss of viable cells and inhibition of arylamine Nacetyltransferase (NAT) activity in a human colon tumor (adenocarcinoma) cell line. The viable cells were determined by trypan blue exclusion under a light microscope. The NAT activity was measured by high performance liquid chromatography for the amounts of N-acetyl-2-aminofluorene (AAF), N-acetyl-p-aminobenzoic acid (N-Ac-PABA), and the remaining 2-aminofluorene (AF) and p-aminobenzoic acid (PABA). The viability and NAT activity in a human colon tumor cell line was inhibited by berberine in a dose-dependent manner, i.e., the higher the concentration of berberine, the higher the inhibition of NAT activity and cell death. The NAT activities measured in the intact human colon tumor cells were decreased over 50% by AAF and NAc-PABA production from acetylation of AF and PABA. The apparent values of Kmoff and Vmax of NAT from colon tumor cells were also inhibited by berberine in cytosols and in intact cells. This report is the first to show that berberine did affect human colon tumor cell NAT activity.
小檗碱用于测定人结肠肿瘤（腺癌）细胞系中活细胞的损失以及芳胺N - 乙酰转移酶（NAT）活性的抑制情况。活细胞通过在光学显微镜下用台盼蓝拒染法测定。NAT活性通过高效液相色谱法测量N - 乙酰 - 2 - 氨基芴（AAF）、N - 乙酰 - 对氨基苯甲酸（N - Ac - PABA）以及剩余的2 - 氨基芴（AF）和对氨基苯甲酸（PABA）的量来确定。小檗碱以剂量依赖方式抑制人结肠肿瘤细胞系中的细胞活力和NAT活性，即小檗碱浓度越高，对NAT活性的抑制和细胞死亡程度越高。通过AF和PABA乙酰化产生的AAF和N - Ac - PABA，使完整人结肠肿瘤细胞中测得的NAT活性降低超过50%。小檗碱在细胞溶质和完整细胞中也抑制了结肠肿瘤细胞NAT的Kmoff和Vmax表观值。本报告首次表明小檗碱确实会影响人结肠肿瘤细胞的NAT活性。
