Study of the genetic determinants of UGT1A1 inducibility by phenobarbital in cultured human hepatocytes
Study of the genetic determinants of UGT1A1 inducibility by phenobarbital in cultured human hepatocytes
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DOI：
10.1097/01.fpc.0000182784.77630.48
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发表时间：
2006-02-01
影响因子：
2.6
通讯作者：
Strom, Stephen C.
中科院分区：
文献类型：
--
作者：
Ramirez, Jacqueline;Komoroski, Bernard J.;Strom, Stephen C.
UGT1A1由苯巴比妥诱导。我们研究了三种常见的UGT1A1变异是否与UGT1A1诱导性的变异性相关。人肝细胞用2mM苯巴比妥孵育2和6天，然后用5 μ M SN-38（1小时），UGT1A1探针。采用高效液相色谱法测定细胞培养基中SN-38糖醛酸化作用。三个UGT1A1启动子变异[-53(TA) (6 bbb7), - 3156G > A和- 3279T > G]被分型。苯巴比妥处理2天（中位诱导倍数= 1.6，范围1.3 - 2.8,n= 28）和6天（中位诱导倍数= 2.8，范围1.6 - 6.4,n= 16），分别有82%和100%的培养物显著诱导UGT1A1的催化活性。处理2 d后，UGT1A1基础活性与折叠诱导呈负相关（Spearman r= - 0.52, P < 0.005）。相比之下，基础状态和诱导状态下UGT1A1活性高度相关（Spearman r = 0.95, P < 0.0001）。治疗6天后观察到类似的结果。诱导制剂（n= 22）和非诱导制剂（n= 6）的等位基因频率差异无统计学意义（P < 0.05）。折叠诱导与任何变异均无相关性（P < 0.05）。基础活性和诱导活性与- 53(TA) （6 bbbb7）相关（由于与- 53 indel几乎完全连锁，与- 3156G > A相关）（P= 0.001）。与- 3279t>g单核苷酸多态性无相关性（P >0.05）。在- 53的指数影响基础表型，似乎限制肝细胞的能力最大诱导后，苯巴比妥。然而，- 53、- 3156和- 3279位点的变异与UGT1A1诱导性的变异无关。
UGT1A1 is induced by phenobarbital. We investigated whether three common UGT1A1 variants are associated with the variability in UGT1A1 inducibility. Human hepatocytes were incubated with 2mM phenobarbital for 2 and 6 days followed by 5 mu M SN-38 (1 h), a UGT1A1 probe. SN-38 glucuronidation in the cell media was measured by high-performance liquid chromatography. Three UGT1A1 promoter variants [-53(TA) (6 > 7), - 3156G > A and - 3279T > G] were genotyped. Significant induction of UGT1A1 catalytic activity was observed in 82% and 100% of the cultures treated with phenobarbital for 2 days (median fold-induction = 1.6, range 1.3 - 2.8; n= 28) and 6 days (median fold-induction = 2.8, range 1.6 - 6.4; n= 16), respectively. After 2 days of treatment, a negative correlation was observed between the UGT1A1 basal activities and the fold-induction (Spearman r= - 0.52, P < 0.005). By contrast, the UGT1A1 activities in the basal and induced states were highly correlated (Spearman r = 0.95, P < 0.0001). Similar results were observed after 6 days of treatment. The allele frequencies were not significantly different between induced (n= 22) and non-induced preparations (n= 6) (P > 0.05). The fold-induction was not associated with any variants (P > 0.05). The basal and induced activities were correlated with - 53( TA) (6 > 7) (and with - 3156G > A due to almost complete linkage with the - 53 indel) (P= 0.001). No association was found with the - 3279T > G single nucleotide polymorphism (P > 0.05). The indel at - 53 affects the basal phenotype and appears to limit the hepatocyte capability of maximal induction after phenobarbital. However, variants at - 53, - 3156 and - 3279 are not associated with variability in UGT1A1 inducibility.