title: In vitro evaluation of cytochrome P450 induction and the inhibition potential of mitragynine, a stimulant alkaloid.
abstract: CYP450 enzymes are key determinants in drug toxicities, reduced pharmacological effect and adverse drug reactions. Mitragynine, an euphoric compound was evaluated for its effects on the expression of mRNAs encoding CYP1A2, CYP2D6 and CYP3A4 and protein expression and resultant enzymatic activity. The mRNA and protein expression of CYP450 isoforms were carried out using an optimized multiplex qRT-PCR assay and Western blot analysis. CYP1A2 and CYP3A4 enzyme activities were evaluated using P450-Glo™ assays. The effects of mitragynine on human CYP3A4 protein expression were determined using an optimized hCYP3A4-HepG2 cell-based assay. An in silico computational method to predict the binding conformation of mitragynine to the active site of the CYP3A4 enzyme was performed and further validated using in vitro CYP3A4 inhibition assays. Mitragynine was found to induce mRNA and protein expression of CYP1A2. For the highest concentration of 25 μM, induction of mRNA was approximately 70% that of the positive control and was consistent with the increased CYP1A2 enzymatic activity. Thus, mitragynine is a significant in vitro CYP1A2 inducer. However, it appeared to be a weak CYP3A4 inducer at the transcriptional level and a weak CYP3A4 enzyme inhibitor. It is therefore, unlikely to have any significant clinical effects on CYP3A4 activity.
authors.affiliation: Malaysian Institute of Pharmaceuticals & Nutraceuticals, Ministry of Science, Technology & Innovation (MOSTI), Pulau Pinang, Malaysia.
authors.forename: Ee Lin
authors.initials: EL
authors.lastname: Lim
authors.forename: Tiong Chai
authors.initials: TC
authors.lastname: Seah
authors.forename: Xue Fen
authors.initials: XF
authors.lastname: Koe
authors.forename: Habibah Abdul
authors.initials: HA
authors.lastname: Wahab
authors.forename: Mohd Ilham
authors.initials: MI
authors.lastname: Adenan
authors.forename: Mohd Fadzly Amar
authors.initials: MF
authors.lastname: Jamil
authors.forename: Mohamed Isa Abdul
authors.initials: MI
authors.lastname: Majid
authors.forename: Mei Lan
authors.initials: ML
authors.lastname: Tan
mesh_terms: D019388:Cytochrome P-450 CYP1A2 / Q000096:biosynthesis* / Q000235:genetics; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics / Q000378:metabolism*; D051544:Cytochrome P-450 CYP3A / Q000096:biosynthesis* / Q000235:genetics; D065692:Cytochrome P-450 CYP3A Inhibitors; D004790:Enzyme Induction / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D056945:Hep G2 Cells; D006801:Humans; D008874:Midazolam / Q000378:metabolism; D062105:Molecular Docking Simulation; D012333:RNA, Messenger / Q000378:metabolism; D046948:Secologanin Tryptamine Alkaloids / Q000494:pharmacology*; D013739:Testosterone / Q000378:metabolism
chemical_list: D065692:Cytochrome P-450 CYP3A Inhibitors; D004791:Enzyme Inhibitors; D012333:RNA, Messenger; D046948:Secologanin Tryptamine Alkaloids; D013739:Testosterone; C504573:CYP1A2 protein, human; D019388:Cytochrome P-450 CYP1A2; D019389:Cytochrome P-450 CYP2D6; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; C001801:mitragynine; D008874:Midazolam