CYP2J subfamily cytochrome P450s in the gastrointestinal tract: expression, localization, and potential functional significance.
CYP2J subfamily cytochrome P450s in the gastrointestinal tract: expression, localization, and potential functional significance.
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DOI：
10.1124/mol.51.6.931
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发表时间：
1997-06
影响因子：
3.6
通讯作者：
D. Zeldin;J. Foley;S. Goldsworthy;M. E. Cook;J. Boyle;Jixiang Ma;C. Moomaw;K. Tomer;C. Steenbergen;Shu Wu
中科院分区：
文献类型：
--
作者：
D. Zeldin;J. Foley;S. Goldsworthy;M. E. Cook;J. Boyle;Jixiang Ma;C. Moomaw;K. Tomer;C. Steenbergen;Shu Wu
我们的实验室最近描述了一种新的人类细胞色素P450花生四烯酸环氧化酶（CYP2J2）和相应的大鼠同源物（CYP2J3），两者都在肝外组织中表达。从人和大鼠肠道制备的RNA的Northern分析表明，CYP2J2和CYP2J3 mrna主要在小肠和结肠中表达。相比之下，使用针对重组CYP2J2的多克隆抗体进行免疫印迹研究显示，CYP2J蛋白在整个胃肠道中表达。用抗cyp2j2 IgG和亲和素-生物素-过氧化物酶检测对福尔马林固定、石蜡包埋的肠道切片进行免疫组化染色，发现自主神经节神经细胞、上皮细胞、肠平滑肌细胞和血管内皮中存在高水平的CYP2J蛋白。使用cyp2j2特异性反义RNA探针原位杂交证实了这种免疫反应性的分布。从人空肠制备的微粒体组分催化花生四烯酸的nadph依赖性代谢为环氧二十碳三烯酸作为主要反应产物。通过气相色谱/质谱法首次记录了人类空肠中环氧二碳三烯酸的存在，为肠道细胞色素P450在体内环氧化花生四烯酸提供了直接证据。我们得出结论，人和大鼠肠道中含有一种花生四烯酸环氧化酶，属于CYP2J亚家族，定位于自主神经节细胞、上皮细胞、平滑肌细胞和血管内皮。除了已知的对肠血管张力的影响外，我们推测CYP2J产物可能参与肠神经肽的释放、肠蠕动的控制和/或肠液/电解质运输的调节。
Our laboratory recently described a new human cytochrome P450 arachidonic acid epoxygenase (CYP2J2) and the corresponding rat homologue (CYP2J3), both of which were expressed in extrahepatic tissues. Northern analysis of RNA prepared from the human and rat intestine demonstrated that CYP2J2 and CYP2J3 mRNAs were expressed primarily in the small intestine and colon. In contrast, immunoblotting studies using a polyclonal antibody raised against recombinant CYP2J2 showed that CYP2J proteins were expressed throughout the gastrointestinal tract. Immunohistochemical staining of formalin-fixed, paraffin-embedded intestinal sections using anti-CYP2J2 IgG and avidin-biotin-peroxidase detection revealed that CYP2J proteins were present at high levels in nerve cells of autonomic ganglia, epithelial cells, intestinal smooth muscle cells, and vascular endothelium. The distribution of this immunoreactivity was confirmed by in situ hybridization using a CYP2J2-specific antisense RNA probe. Microsomal fractions prepared from human jejunum catalyzed the NADPH-dependent metabolism of arachidonic acid to epoxyeicosatrienoic acids as the principal reaction products. Direct evidence for the in vivo epoxidation of arachidonic acid by intestinal cytochrome P450 was provided by documenting, for the first time, the presence of epoxyeicosatrienoic acids in human jejunum by gas chromatography/mass spectrometry. We conclude that human and rat intestine contain an arachidonic acid epoxygenase belonging to the CYP2J subfamily that is localized to autonomic ganglion cells, epithelial cells, smooth muscle cells, and vascular endothelium. In addition to the known effects on intestinal vascular tone, we speculate that CYP2J products may be involved in the release of intestinal neuropeptides, control of intestinal motility, and/or modulation of intestinal fluid/electrolyte transport.