Molecular evidence for cytochrome P450 2E1 expressed in human brain

We have carried out polymerase chain reaction (PCR) to investigate if cytochrome P450 2E1 (CYP2E1) is expressed in human brain. A 1.4 kb DNA fragment was clearly amplified using recombinant phage DNAs, isolated from human brain cDNA library, as PCR templates. This DNA fragment was successively subjected to Southern blot analysis, nested PCR and DNA sequencing and finally its internal structure turned out to be exactly same as the previously reported liver CYP2E1. No deletions or insertions were identified. And there was no alternative RNA splicing event between these two tissues. Our results are indicative of the fact that CYP2E1 is actually expressed in human brain although its level is extremely low. Results strongly support the hypothesis that CYP2E1 has to be related to brain toxicity in any means and should facilitate the understanding of the function of CYP2E1 in the brain.