Is CYP1A1 induction always related to AHR signaling pathway

摘要: Humans are daily subjected to ever increasing amounts of exogenous compounds. Some them capable inducing cytochrome P450s, a process that allows the cell adapt changes in its chemical environment. One most widely CYP studied is CYP1A1 because it metabolises large number xenobiotics cytotoxic and/or mutagenic derivatives. To date, results from literature indicate induction does not only involve classical activation cascade Ah receptor, e.g. binding ligand AhR, heterodimerisation with Arnt protein, constitution complex XRE responsive element and subsequent gene activation. Indeed, some do activate expression spite their inability compete TCDD for AhR. Other signaling pathways must therefore also be considered. Firstly, inducer compounds could very weak AhR ligands or may metabolized into form which turn receptor. A second hypothesis would these molecules act through other cascades. At this time, two seem implicated. concerns RARs signal transduction pathway, as already described retinoic acid. The tyrosine kinase activation, but precise relationship between CYPA1 remains yet established. For moment there still black box needs investigated.