PURPOSE: Compelling evidence supports the presence of P450 enzymes (CYPs) in the central nervous system (CNS). However, little information is available on the localization and function of CYPs in the drug-resistant epileptic brain. We have evaluated the pattern of expression of the specific enzyme CYP3A4 and studied its co-localization with MDR1. We also determined whether an association exists between CYP3A4 expression and cell survival. METHODS: Brain specimens were obtained from eight patients undergoing resection to relieve drug-resistant seizures or to remove a cavernous angioma. Each specimen was partitioned for either immunostaining or primary culture of human endothelial cells and astrocytes. Immunostaining was performed using anti-CYP3A4, MDR1, GFAP, or NeuN antibodies. High performance liquid chromatography-ultraviolet (HPLC-UV) analysis was used to quantify carbamazepine (CBZ) metabolism by these cells. CYP3A4 expression was correlated to DAPI) condensation, a marker of cell viability. Human embryonic kidney (HEK) cells were transfected with 4',6-diamidino-2-phenylindole (CYP3A4 to further evaluate the link between CYP3A4 levels, CBZ metabolism, and cell viability. KEY FINDINGS: CYP3A4 was expressed by blood-brain barrier (BBB) endothelial cells and by the majority of neurons (75 ± 10%). Fluorescent immunostaining showed coexpression of CYP3A4 and MDR1 in endothelial cells and neurons. CYP3A4 expression inversely correlated with DAPI nuclear condensation. CYP3A4 overexpression in HEK cells conferred resistance to cytotoxic levels of carbamazepine. CYP3A4 levels positively correlated with the amount of CBZ metabolized. SIGNIFICANCE: CYP3A4 brain expression is not only associated with drug metabolism but may also represent a cytoprotective mechanism. Coexpression of CYP3A4 and MDR1 may be involved in cell survival in the diseased brain. Wiley Periodicals, Inc.
PURPOSE: Compelling evidence supports the presence of P450 enzymes (CYPs) in the central nervous system (CNS). However, little information is available on the localization and function of CYPs in the drug-resistant epileptic brain. We have evaluated the pattern of expression of the specific enzyme CYP3A4 and studied its co-localization with MDR1. We also determined whether an association exists between CYP3A4 expression and cell survival. METHODS: Brain specimens were obtained from eight patients undergoing resection to relieve drug-resistant seizures or to remove a cavernous angioma. Each specimen was partitioned for either immunostaining or primary culture of human endothelial cells and astrocytes. Immunostaining was performed using anti-CYP3A4, MDR1, GFAP, or NeuN antibodies. High performance liquid chromatography-ultraviolet (HPLC-UV) analysis was used to quantify carbamazepine (CBZ) metabolism by these cells. CYP3A4 expression was correlated to DAPI) condensation, a marker of cell viability. Humanembryonic kidney (HEK) cells were transfected with 4',6-diamidino-2-phenylindole (CYP3A4 to further evaluate the link between CYP3A4 levels, CBZ metabolism, and cell viability. KEY FINDINGS:CYP3A4 was expressed by blood-brain barrier (BBB) endothelial cells and by the majority of neurons (75 ± 10%). Fluorescent immunostaining showed coexpression of CYP3A4 and MDR1 in endothelial cells and neurons. CYP3A4 expression inversely correlated with DAPI nuclear condensation. CYP3A4 overexpression in HEK cells conferred resistance to cytotoxic levels of carbamazepine. CYP3A4 levels positively correlated with the amount of CBZ metabolized. SIGNIFICANCE: CYP3A4 brain expression is not only associated with drug metabolism but may also represent a cytoprotective mechanism. Coexpression of CYP3A4 and MDR1 may be involved in cell survival in the diseased brain. Wiley Periodicals, Inc.
Authors: W Xie; J L Barwick; M Downes; B Blumberg; C M Simon; M C Nelson; B A Neuschwander-Tetri; E M Brunt; P S Guzelian; R M Evans Journal: Nature Date: 2000-07-27 Impact factor: 49.962
Authors: Petra Bittigau; Marco Sifringer; Kerstin Genz; Ellen Reith; Dana Pospischil; Suresh Govindarajalu; Mark Dzietko; Stefanie Pesditschek; Ingrid Mai; Krikor Dikranian; John W Olney; Chrysanthy Ikonomidou Journal: Proc Natl Acad Sci U S A Date: 2002-11-04 Impact factor: 11.205
Authors: S M Dombrowski; S Y Desai; M Marroni; L Cucullo; K Goodrich; W Bingaman; M R Mayberg; L Bengez; D Janigro Journal: Epilepsia Date: 2001-12 Impact factor: 5.864
Authors: Shailesh Y Desai; Matteo Marroni; Luca Cucullo; Ljiljana Krizanac-Bengez; Marc R Mayberg; Mohammed T Hossain; Gerald G Grant; Damir Janigro Journal: Endothelium Date: 2002
Authors: M Marroni; M L Agrawal; K Kight; K L Hallene; M Hossain; L Cucullo; K Signorelli; S Namura; W Bingaman; D Janigro Journal: Neuroscience Date: 2003 Impact factor: 3.590
Authors: Hassan R Dhaini; Dafydd G Thomas; Thomas J Giordano; Timothy D Johnson; J Sybil Biermann; Kirsten Leu; Paul F Hollenberg; Laurence H Baker Journal: J Clin Oncol Date: 2003-07-01 Impact factor: 44.544
Authors: A Palmini; I Najm; G Avanzini; T Babb; R Guerrini; N Foldvary-Schaefer; G Jackson; H O Lüders; R Prayson; R Spreafico; H V Vinters Journal: Neurology Date: 2004-03-23 Impact factor: 9.910
Authors: Mark E Schmidt; Peter de Boer; Randolph Andrews; Martine Neyens; Stefaan Rossenu; Demiana William Falteos; Erik Mannaert Journal: Psychopharmacology (Berl) Date: 2012-07-07 Impact factor: 4.530
Authors: Anika M S Hartz; Anton Pekcec; Emma L B Soldner; Yu Zhong; Juli Schlichtiger; Bjoern Bauer Journal: Mol Pharm Date: 2017-03-02 Impact factor: 4.939
Authors: Christopher A Palmiotti; Shikha Prasad; Pooja Naik; Kaisar M D Abul; Ravi K Sajja; Anilkumar H Achyuta; Luca Cucullo Journal: Pharm Res Date: 2014-08-07 Impact factor: 4.200