Characterization of recombinant CYP2C11: a vitamin D 25-hydroxylase and 24-hydroxylase.
Characterization of recombinant CYP2C11: a vitamin D 25-hydroxylase and 24-hydroxylase.
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DOI：
10.1152/ajpendo.00201.2004
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发表时间：
2005-04
期刊：
影响因子：
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通讯作者：
Mehrdad Rahmaniyan;K. Patrick;N. Bell
中科院分区：
文献类型：
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作者：
Mehrdad Rahmaniyan;K. Patrick;N. Bell
进行研究以进一步表征在杆状病毒感染的昆虫细胞中表达的雄性特异性肝重组微粒体维生素D 25-羟化酶CYP 2C 11，并确定其是否也是维生素D 24-羟化酶。25-和24-羟化酶的活性进行了比较，与其他10个重组肝微粒体细胞色素P-450酶表达的杆状病毒感染的昆虫细胞。其中每种都含有25-羟基化维生素D2、维生素D3、1 α-羟基维生素D2（1alphaOHD 2）和1 α-羟基维生素D3（1alphaOHD 3）。CYP 2C 11对这些底物具有最大的活性，但维生素D3除外，其活性与其他四种酶相同。CYP 2C 11对25-羟基化的作用顺序为1alphaOHD 3> 1alphaOHD 2>维生素D2 >维生素D3。每种重组细胞色素P-450酶24-羟基化1alphaOHD 2。CYP 2C 11活性最高。24-1alphaOHD 3的羟基化非常低，而维生素D3则没有。仅CYP 2C 11 24-羟基化维生素D2。维生素D代谢物的结构，包括24-羟基维生素D2，1，24（S）-二羟基维生素D2和1，24-二羟基维生素D3，通过HPLC和气相色谱保留时间和特征质谱裂解模式进行了确认。在雄性大鼠中，垂体切除术显著降低了体重、肝脏重量、肝脏CYP 2C 11 mRNA表达以及1alphaOHD 2的24-和25-羟基化。CYP 2 J3和CYP 2 R1 mRNA表达无变化。在雄性大鼠肝细胞中，与未培养的细胞相比，培养24 h后，CYP 2C 11 mRNA表达和24-和25-羟基化显著降低。CYP 2 J3和CYP 2 R1的表达增加或没有变化。结论：CYP 2C 11是一种雄性特异性肝微粒体维生素D25-羟化酶，可使维生素D2、维生素D3、1alphaOHD 2和1alphaOHD 3羟化。CYP 2C 11也是一种维生素D 24-羟化酶。
Studies were performed to further characterize the male-specific hepatic recombinant microsomal vitamin D 25-hydroxlase CYP2C11, expressed in baculovirus-infected insect cells, and determine whether it is also a vitamin D 24-hydroxylase. 25- and 24-hydroxylase activities were compared with those of 10 other recombinant hepatic microsomal cytochrome P-450 enzymes expressed in baculovirus-infected insect cells. Each of them 25-hydroxylated vitamin D2, vitamin D3, 1alpha-hydroxyvitamin D2 (1alphaOHD2), and 1alpha-hydroxyvitamin D3 (1alphaOHD3). CYP2C11 had the greatest activity with these substrates, except vitamin D3, which had the same activity as four of the other enzymes. The descending order of 25-hydroxylation by CYP2C11 was 1alphaOHD3 > 1alphaOHD2 > vitamin D2 > vitamin D3. Each of the recombinant cytochrome P-450 enzymes 24-hydroxylated 1alphaOHD2. CYP2C11 had the greatest activity. 24-Hydroxylation of 1alphaOHD3 was very low, and there was none with vitamin D3. Only CYP2C11 24-hydroxylated vitamin D2. Structures of vitamin D metabolites, including 24-hydroxyvitamin D2, 1,24(S)-dihydroxyvitamin D2, and 1,24-dihydroxyvitamin D3, were confirmed by HPLC and gas chromatography retention times and characteristic mass spectrometric fragmentation patterns. In male rats, hypophysectomy significantly reduced body weight, liver weight, hepatic CYP2C11 mRNA expression, and 24- and 25-hydroxylation of 1alphaOHD2. Expression of CYP2J3 and CYP2R1 mRNA did not change. In male rat hepatocytes, CYP2C11 mRNA expression and 24- and 25-hydroxylation were significantly reduced after culture for 24 h compared with uncultured cells. Expression of CYP2J3 and CYP2R1 either increased or did not change. It is concluded that CYP2C11 is a male-specific hepatic microsomal vitamin D 25-hydroxylase that hydroxylates vitamin D2, vitamin D3, 1alphaOHD2, and 1alphaOHD3. CYP2C11 is also a vitamin D 24-hydroxylase.