Chung J G, Wu L T, Chu C B, Jan J Y, Ho C C, Tsou M F, Lu H F, Chen G W, Lin J G, Wang T F
Department of Microbiology, China Medical College, Taichung, Taiwan, Republic of China.
Food Chem Toxicol. 1999 Apr;37(4):319-26. doi: 10.1016/s0278-6915(99)00016-2.
Berberine was used to determine inhibition of arylamine N-acetyltransferase (NAT) activity in human bladder tumour cells. The NAT activity was measured by HPLC assaying for the amounts of N-acetyl-2-aminofluorene (AAF) and N-acetyl-p-aminobenzoic acid (N-Ac-PABA) and remaining 2-aminofluorene (AF) and p-aminobenzoic acid (PABA). Two assay systems were performed, one with cellular cytosols, the other with intact bladder tumour cell suspensions. The NAT activity in human bladder tumour cells was inhibited by berberine in a dose-dependent manner, that is, the higher the concentration of berberine, the higher the inhibition of NAT activity. The values of apparent Km and Vmax calculated from cytosol NAT and intact cells were also decreased by berberine. This report is the first demonstration to show berberine did affect human bladder tumour cell NAT activity.
小檗碱用于测定其对人膀胱肿瘤细胞中芳胺N - 乙酰转移酶（NAT）活性的抑制作用。通过高效液相色谱法测定N - 乙酰 - 2 - 氨基芴（AAF）和N - 乙酰 - 对氨基苯甲酸（N - Ac - PABA）的量以及剩余的2 - 氨基芴（AF）和对氨基苯甲酸（PABA）来测量NAT活性。进行了两种测定系统，一种是细胞胞质溶胶，另一种是完整的膀胱肿瘤细胞悬液。小檗碱以剂量依赖性方式抑制人膀胱肿瘤细胞中的NAT活性，即小檗碱浓度越高，对NAT活性的抑制作用越强。从小檗碱处理的胞质溶胶NAT和完整细胞计算出的表观Km和Vmax值也降低。本报告首次证明小檗碱确实会影响人膀胱肿瘤细胞的NAT活性。
