High impact information on CYP2B

• There was no significant difference in expression of mEH, CYP2B7, or NADPH OR in smokers compared with nonsmokers [1].
• CYP2B7 expression was evaluated because, although little is known of its substrate specificity, it is expressed at high levels in human lung tissue [1].
• New proteins in the rat CYP2B subfamily: presence in liver microsomes of the constitutive CYP2B3 protein and the phenobarbital-inducible protein product of alternatively spliced CYP2B2 mRNA [2].
• These results demonstrate the existence in rat liver of two new CYP2B proteins: CYP2B3, the major constitutive CYP2B form, and CYP2B2v, which represents a rare case of non-aberrant alternative splicing among xenobiotic-metabolizing P450s [2].
• Inductions of CYP1A1 and CYP2B in hepatocytes cryopreserved with WPEs were similar to those in fresh hepatocytes [3].

Biological context of CYP2B

• Quantitative structure-activity relationships (QSARs) within cytochromes P450 2B (CYP2B) subfamily enzymes: the importance of lipophilicity for binding and metabolism [4].
• Although the linear relationships between lipophilicity and CYP2B-related activity point to a major role for desolvation of the enzyme binding site in the overall interaction, it is noted that there may be an optimal log P value displayed by preferred substrates as shown by parabolic relationships with this lipophilic parameter [4].
• Western blot analyses of scup livers using anti-human CAR antisera revealed the occurrence of a putative CAR homologue in nuclear and cytoplasmic fractions, but no nuclear accumulation of CAR following TCPOBOP treatment, which is a first step regulating the transcriptional activation of CYP2B genes in mouse [5].

Associations of CYP2B with chemical compounds

• The results of qualitative structure-activity relationship (QSAR) analysis are reported for several series of compounds which act as substrates for mammalian CYP2B subfamily enzymes, together with a homologous series of aliphatic primary amines which are known to inhibit CYP2B enzymes [4].
• The mammalian constitutively active receptor (CAR) is a novel ligand-activated transcription factor that participates in controlling the expression of cytochrome P450 2B (CYP2B) genes in response to pharmaceutical agents (phenobarbital) and halogenated aromatic hydrocarbons (ortho-substituted PCBs) [5].

References