keyword
MENU ▼
Read by QxMD icon Read
search

3A4

keyword
https://www.readbyqxmd.com/read/27925256/pharmacokinetic-drug-drug-interactions-of-tyrosine-kinase-inhibitors-a-focus-on-cytochrome-p450-transporters-and-acid-suppression-therapy
#1
REVIEW
Caroline Gay, Delphine Toulet, Pascal Le Corre
The extensive use of tyrosine kinase inhibitors (TKI's) in hematology and oncology has shown that these drugs have a significant potential for drug-drug interactions. Since these drugs have a rather low therapeutic window, some drug interactions are of particular clinical relevance either on drug toxicity or on patient's response. Significant interactions occur with concomitant use of acid-suppressive therapy leading to a decreased oral bioavailability. However, such interactions are drug dependent according to their solubility pattern and to the duration of action of acid-suppressive therapy, which is coprescribed...
December 7, 2016: Hematological Oncology
https://www.readbyqxmd.com/read/27913846/potent-mutagenicity-of-some-non-planar-tri-and-tetrachlorinated-biphenyls-in-mammalian-cells-human-cyp2e1-being-a-major-activating-enzyme
#2
Yungang Liu, Keqi Hu, Hansi Jia, Guifang Jin, Hansruedi Glatt, Hao Jiang
Polychlorinated biphenyls (PCBs) have been classified as human carcinogens. Mutagenicity of lower chlorinated biphenyls as well as activation of transcription factors by some other congeners may contribute to the carcinogenicity of PCBs. Recently, we reported that human CYP2E1 activates mono- and dichlorobiphenyls to mutagens. However, mutagenicity of other PCBs and the involvement of other CYPs remained unknown. In this study, Chinese hamster V79-derived cell lines genetically engineered for expression of individual human CYP enzymes and a human hepatocyte (L-02) line endogenously expressing various CYPs were used to determine the activities of several tri- and tetrachlorobiphenyls to induce micronuclei and gene mutations...
December 2, 2016: Archives of Toxicology
https://www.readbyqxmd.com/read/27909995/solithromycin-a-novel-fluoroketolide-for-the-treatment-of-community-acquired-bacterial-pneumonia
#3
REVIEW
George G Zhanel, Erika Hartel, Heather Adam, Sheryl Zelenitsky, Michael A Zhanel, Alyssa Golden, Frank Schweizer, Bala Gorityala, Philippe R S Lagacé-Wiens, Andrew J Walkty, Alfred S Gin, Daryl J Hoban, Joseph P Lynch, James A Karlowsky
Solithromycin is a novel fluoroketolide developed in both oral and intravenous formulations to address increasing macrolide resistance in pathogens causing community-acquired bacterial pneumonia (CABP). When compared with its macrolide and ketolide predecessors, solithromycin has several structural modifications which increase its ribosomal binding and reduce its propensity to known macrolide resistance mechanisms. Solithromycin, like telithromycin, affects 50S ribosomal subunit formation and function, as well as causing frame-shift errors during translation...
December 1, 2016: Drugs
https://www.readbyqxmd.com/read/27904973/platelet-reactivity-and-clinical-outcomes-in-patients-using-cyp3a4-metabolized-statins-with-clopidogrel-in-percutaneous-coronary-intervention
#4
Jin Sup Park, Kwang Soo Cha, Hye Won Lee, Jun-Hyok Oh, Jung Hyun Choi, Han Cheol Lee, Taek Jong Hong, Hyo Soo Kim
Statins are primarily metabolized by cytochrome P450 3A4 (CYP3A4), which reduces clopidogrel to its active metabolite. Recent studies suggest that CYP3A4-metabolized statins attenuate clopidogrel's anti-aggregatory effect on platelets. We aimed to assess the impact of concomitant CYP3A4-metabolized statin and clopidogrel use on antiplatelet activity and clinical outcomes in patients undergoing percutaneous coronary intervention (PCI). We enrolled 1187 patients from the HOST-ASSURE trial with platelet reactivity unit (PRU) values at both baseline and 1 month...
November 30, 2016: Heart and Vessels
https://www.readbyqxmd.com/read/27902864/in-vitro-and-in-vivo-metabolic-activation-of-berbamine-to-quinone-methide-intermediate
#5
Yao Sun, Tong Yao, Hui Li, Ying Peng, Jiang Zheng
Berbamine (BBM) is a bisbenzylisoquinoline alkaloid isolated from herbal medicine Berberis amurensis. BBM has been widely used for the treatment of leukemia. Recent studies demonstrated that exposure to BBM can give rise to cytotoxicity. The major objective of this study was to explore the metabolic activation of BBM in vitro and in vivo. Two oxidative metabolites (M1 and M2) and an N-acetylcysteine (NAC) conjugate (M3) were detected in human liver microsomal incubations of BBM supplemented with NAC, and the formation of all metabolites was NADPH dependent...
November 30, 2016: Journal of Biochemical and Molecular Toxicology
https://www.readbyqxmd.com/read/27897366/active-site-crowding-of-p450-3a4-as-a-strategy-to-alter-its-selectivity
#6
Paolo Schiavini, Kin J Cheong, Nicolas Moitessier, Karine Auclair
Substrate promiscuous enzymes are a promising starting point for the development of versatile biocatalysts. In this study, human cytochrome P450 3A4, known for its ability to metabolize hundreds of drugs, was engineered to alter its regio- and stereoselectivity. Rational mutagenesis was used to specifically introduce steric hindrance in the large active site of P450 3A4 and favour oxidation at a more sterically accessible position on the substrate. Hydroxylation of a synthetic precursor of (R)-lisofylline, a compound under investigation for its anti-inflammatory properties, was chosen as a first proof-of-principle application of our protein engineering strategy...
November 29, 2016: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/27896690/elucidating-the-plasma-and-liver-pharmacokinetics-of-simeprevir-in-special-populations-using-physiologically-based-pharmacokinetic-modelling
#7
Jan Snoeys, Maria Beumont, Mario Monshouwer, Sivi Ouwerkerk-Mahadevan
The disposition of simeprevir (SMV) in humans is characterised by cytochrome P450 3A4 metabolism and hepatic uptake by organic anion transporting polypeptide 1B1/3 (OATP1B1/3). This study was designed to investigate SMV plasma and liver exposure upon oral administration in subjects infected with hepatitis C virus (HCV), in subjects of Japanese or Chinese origin, subjects with organ impairment and subjects with OATP genetic polymorphisms, using physiologically based pharmacokinetic modelling. Simulations showed that compared with healthy Caucasian subjects, SMV plasma exposure was 2...
November 29, 2016: Clinical Pharmacokinetics
https://www.readbyqxmd.com/read/27894202/rolapitant-for-the-prevention-of-delayed-nausea-and-vomiting-over-initial-and-repeat-courses-of-emetogenic-chemotherapy
#8
Bernardo Rapoport, Ronwyn van Eeden, Teresa Smit
Introduction Chemotherapy-induced nausea and vomiting (CINV) is a debilitating side effect of many cytotoxic chemotherapy regimens. Although sustained antiemetic control across repeated chemotherapy cycles is important for cancer treatment continuation, few studies have investigated the efficacy of antiemetic prophylaxis over multiple chemotherapy cycles. Areas Covered Here we discuss the use of antiemetic hydroxytryptamine type 3 (5-HT3) receptor and neurokinin (NK)-1 receptor antagonists for prevention of CINV, limiting our review to clinical trials in the context of multiple-cycle chemotherapy, with a focus on the NK-1 receptor antagonist rolapitant...
November 29, 2016: Expert Review of Clinical Pharmacology
https://www.readbyqxmd.com/read/27890698/clementine-juice-has-the-potential-for-drug-interactions-in-vitro-comparison-with-grapefruit-and-mandarin-juice
#9
Dirk Theile, Nicolas Hohmann, Dominik Kiemel, Giuseppe Gattuso, Davide Barreca, Gerd Mikus, Walter Emil Haefeli, Vedat Schwenger, Johanna Weiss
Adverse drug interactions due to grapefruit juice are well known prompting warnings even in drug labels. Similar issues have not been reported for clementines and available data is scarce, despite of genetic descent. We observed substantially increased tacrolimus trough concentrations in a renal transplant patient consuming high clementine amounts and, thus, scrutinised the effects of clementine juice on drug metabolism and drug transporters in vitro and compared it to the effects of mandarin and grapefruit juice...
November 24, 2016: European Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/27853934/evaluation-of-in-vitro-cytochrome-p450-inhibition-and-in-vitro-fate-of-structurally-diverse-n-oxide-metabolites-case-studies-with-clozapine-levofloxacin-roflumilast-voriconazole-and-zopiclone
#10
Poonam Giri, Sneha Naidu, Nirmal Patel, Harilal Patel, Nuggehally R Srinivas
BACKGROUND AND OBJECTIVES: The role of metabolite(s) to elicit potential clinical drug-drug interaction (DDI) via cytochrome P450 enzymes (CYP) is gaining momentum. In this context, the role of N-oxides for in vitro CYP inhibition has not been evaluated. The objectives of this study were: (a) to examine in vitro CYP inhibition of N-oxides of clozapine, levofloxacin, roflumilast, voriconazole and zopiclone in a tiered approach and (b) evaluate in vitro fate of aforementioned N-oxides examined in recombinant CYPs, human microsomes and hepatocytes...
November 16, 2016: European Journal of Drug Metabolism and Pharmacokinetics
https://www.readbyqxmd.com/read/27842484/strong-induction-of-cytochrome-p450-1a-3a-but-not-p450-2b-in-cultured-hepatocytes-from-common-marmosets-and-cynomolgus-monkeys-by-typical-human-p450-inducing-agents
#11
Shotaro Uehara, Yasuhiro Uno, Takako Suzuki, Takashi Inoue, Masahiro Utoh, Erika Sasaki, Hiroshi Yamazaki
BACKGROUND: Common marmosets (Callithrix jacchus) and cynomolgus monkeys (Macaca fascicularis) are used as non-human primate models in preclinical studies for drug development. OBJECTIVE: The assessment of P450 induction in hepatocytes from marmosets and cynomolgus monkeys was performed using typical P450 inducers. METHODS: Induction of cytochrome P450 1-4 family enzymes was analyzed in two lots of cultured hepatocytes from common marmosets and cynomolgus monkeys after 24-h treatment with typical human P450 inducing agents by real-time reverse transcription-polymerase chain reaction...
November 14, 2016: Drug Metabolism Letters
https://www.readbyqxmd.com/read/27822915/analysis-of-the-variable-factors-influencing-tacrolimus-blood-concentration-during-the-switch-from-continuous-intravenous-infusion-to-oral-administration-after-allogeneic-hematopoietic-stem-cell-transplantation
#12
Kimitaka Suetsugu, Hiroaki Ikesue, Toshihiro Miyamoto, Motoaki Shiratsuchi, Nanae Yamamoto-Taguchi, Yuichi Tsuchiya, Kumi Matsukawa, Mayako Uchida, Hiroyuki Watanabe, Koichi Akashi, Satohiro Masuda
The aim of this retrospective study was to identify variable factors affecting tacrolimus blood concentration during the switch from continuous intravenous infusion to twice-daily oral administration in allogeneic hematopoietic stem cell transplant recipients (n = 73). The blood concentration/dose ratio of tacrolimus immediately before the change from continuous infusion (C/Div) was compared with that between 3 and 5 days after the change to oral administration (C/Dpo). Median (C/Dpo)/(C/Div) was 0.21 (range 0...
November 7, 2016: International Journal of Hematology
https://www.readbyqxmd.com/read/27822600/clarithromycin-midazolam-and-digoxin-application-of-pbpk-modeling-to-gain-new-insights-into-drug-drug-interactions-and-co-medication-regimens
#13
Daniel Moj, Nina Hanke, Hannah Britz, Sebastian Frechen, Tobias Kanacher, Thomas Wendl, Walter Emil Haefeli, Thorsten Lehr
Clarithromycin is a substrate and mechanism-based inhibitor of cytochrome P450 (CYP) 3A4 as well as a substrate and competitive inhibitor of P-glycoprotein (P-gp) and organic anion-transporting polypeptides (OATP) 1B1 and 1B3. Administered concomitantly, clarithromycin causes drug-drug interactions (DDI) with the victim drugs midazolam (CYP3A4 substrate) and digoxin (P-gp substrate). The objective of the presented study was to build a physiologically based pharmacokinetic (PBPK) DDI model for clarithromycin, midazolam, and digoxin and to exemplify dosing adjustments under clarithromycin co-treatment...
November 7, 2016: AAPS Journal
https://www.readbyqxmd.com/read/27819189/inhibitory-effects-of-curculigoside-on-human-liver-cytochrome-p450-enzymes
#14
Jixiao Lang, Wei Li, Jingming Zhao, Kaiyou Wang, Dexi Chen
1. Curculigoside possesses numerous pharmacological activities, and however, little data available for the effects of curculigoside on the activity of human liver cytochrome P450 (CYP) enzymes. 2. This study investigates the inhibitory effects of curculigoside on the main human liver CYP isoforms. In this study, the inhibitory effects of curculigoside on the eight human liver CYP isoforms 1A2, 2A6, 2E1, 2D6, 2C9, 2C19, 2C8, and 3A4 were investigated in human liver microsomes. 3. The results indicated that curculigoside could inhibit the activity of CYP1A2, CYP2C8, and CYP3A4, with IC50 values of 15...
November 5, 2016: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/27802299/protective-effects-of-essential-oils-as-natural-antioxidants-against-hepatotoxicity-induced-by-cyclophosphamide-in-mice
#15
Salah A Sheweita, Lobna S El-Hosseiny, Munther A Nashashibi
Clinical application of cyclophosphamide (CP) as an anticancer drug is often limited due to its toxicity. CP is metabolized mainly in the liver by cytochrome P450 system into acrolein which is the proximate toxic metabolite. Many different natural antioxidants were found to alleviate the toxic effects of various toxic agents via different mechanisms. Therefore, the present study aimed at investigating the role of essential oils extracted from fennel, cumin and clove as natural antioxidants in the alleviation of hepatotoxicity induced by CP through assessment of hepatotoxicity biomarkers (AST, ALT, ALP), histopathology of liver tissues as well as other biochemical parameters involved in the metabolism of CP...
2016: PloS One
https://www.readbyqxmd.com/read/27798211/daclatasvir-30-mg-day-is-the-correct-dose-for-patients-taking-atazanavir-cobicistat
#16
E J Smolders, E P H Colbers, C T M M de Kanter, K Velthoven-Graafland, J P H Drenth, D M Burger
BACKGROUND: Atazanavir is boosted with the cytochrome P450 (CYP) 3A4 inhibitor ritonavir. When combined with the CYP3A4 substrate daclatasvir, the daclatasvir dosage should be reduced from 60 to 30 mg once daily. Recently, cobicistat was licensed as a CYP3A booster and used with atazanavir. OBJECTIVES: To determine whether the fixed-dose combination of atazanavir/cobicistat has an influence on daclatasvir pharmacokinetics comparable to that of the separate agents atazanavir and ritonavir...
October 20, 2016: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/27769111/cytochrome-p450-mediated-bioactivation-of-saracatinib
#17
Jiaming Chen, Ying Peng, Jiang Zheng
Saracatinib, is a highly selective Src kinase inhibitor against all Src kinase family members and has demonstrated anti-cancer effects in preclinical models. Unfortunately, it has shown multiple adverse effects during its clinical trials, along with time-dependent inhibition of P450 enzymes. The major objective of this study was to identify reactive metabolites of saracatinib in vitro and in vivo. Four oxidative metabolites (M1-M4) were detected in rat and human liver microsomal incubation systems after exposure to saracatinib...
October 21, 2016: Chemical Research in Toxicology
https://www.readbyqxmd.com/read/27766562/a-physiologically-based-pharmacokinetic-model-to-predict-human-fetal-exposure-for-a-drug-metabolized-by-several-cyp450-pathways
#18
Maïlys De Sousa Mendes, Gabrielle Lui, Yi Zheng, Claire Pressiat, Deborah Hirt, Elodie Valade, Naïm Bouazza, Frantz Foissac, Stephane Blanche, Jean-Marc Treluyer, Saik Urien, Sihem Benaboud
BACKGROUND: Pregnant women and their fetuses are exposed to numerous drugs; however, they are orphan populations with respect to the safety and efficacy of drugs. Therefore, the prediction of maternal and fetal drug exposure prior to administration would be highly useful. METHODS: A physiologically-based pharmacokinetic (PBPK) model for nevirapine, which is metabolized by the cytochrome P450 (CYP) 3A4, 2B6 and 2D6 pathways, was developed to predict maternal and fetal pharmacokinetics (PK)...
October 21, 2016: Clinical Pharmacokinetics
https://www.readbyqxmd.com/read/27761064/human-cytochrome-p450-enzyme-modulation-by-gymnema-sylvestre-a-predictive-safety-evaluation-by-lc-ms-ms
#19
Bera Rammohan, Karmakar Samit, Das Chinmoy, Saha Arup, Kundu Amit, Sarkar Ratul, Karmakar Sanmoy, Adhikari Dipan, Sen Tuhinadri
BACKGROUND: Traditionally GS is used to treat diabetes mellitus. Drug-herb interaction of GS via cytochrome P450 enzyme system by substrate cocktail method using HLM has not been reported. OBJECTIVE: To evaluate the in-vitro modulatory effects of GS extracts (aqueous, methanol, ethyl acetate, chloroform and n-hexane) and deacylgymnemic acid (DGA) on human CYP1A2, 2C8, 2C9, 2D6 and 3A4 activities in HLM. MATERIAL AND METHODS: Probe substrate-based LCMS/MS method was established for all CYPs...
July 2016: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/27756246/identification-of-potential-candidate-genes-for-hypertensive-nephropathy-based-on-gene-expression-profile
#20
Zhi Chen, Hao Wu, Guohua Wang, Ye Feng
BACKGROUND: This study was aimed to explore the molecular mechanisms of hypertensive nephropathy (HTN). METHODS: Gene expression profile of GSE37460, which based on 27 healthy living donor samples (HTN group) and 15 hypertensive nephropathy samples (control group), were downloaded from Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) between two groups were identified. STRING database was used to reveal protein-protein interaction (PPI) network of DEGs, followed by the functional enrichment analysis of the PPI network...
October 18, 2016: BMC Nephrology
keyword
keyword
83670
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"