Results 21 to 30 of about 4,522 (127)

CYP3A Activity in End-of-Life Cancer Patients Measured by 4β-Hydroxycholesterol/cholesterol Ratio, in Men and Women. [PDF]

Cancers (Basel), 2021
More than 50% of all drugs are metabolized by the cytochrome P450 3A enzyme (CYP3A). The aim of this study was to investigate if the CYP3A activity, measured by the endogenous marker 4β-hydroxycholesterol/cholesterol ratio (4β-OHC/C), is changed during ...
Bergström H, Helde Frankling M, Klasson C, Lövgren Sandblom A, Diczfalusy U, Björkhem-Bergman L.   +5 more
europepmc   +2 more sources

Plasma 4β-Hydroxycholesterol Predicts Ribociclib CYP3A-Mediated Metabolism, but Not Plasma Exposure, in Patients with Primary Brain Cancer. [PDF]

Cancers (Basel)
Background/Objectives: This study aimed to evaluate the potential utility of plasma 4β-hydroxycholesterol (4β-OHC) as an endogenous biomarker of hepatic CYP3A activity for predicting ribociclib metabolism and systemic pharmacokinetics in patients with ...
Wickramasinghe C, Bao X, Jiang Y, Jiang J, Yue Y, Sanai N, Li J.   +6 more
europepmc   +2 more sources

Comparative performance of oral midazolam clearance and plasma 4β-hydroxycholesterol to explain interindividual variability in tacrolimus clearance. [PDF]

Br J Clin Pharmacol, 2016
We compared the CYP3A4 metrics weight-corrected midazolam apparent oral clearance (MDZ Cl/F/W) and plasma 4β-hydroxycholesterol/cholesterol (4β-OHC/C) as they relate to tacrolimus (TAC) Cl/F/W in renal transplant recipients.status ...
Vanhove T, de Jonge H, de Loor H, Annaert P, Diczfalusy U, Kuypers DR.   +5 more
europepmc   +2 more sources

PHENOTYPING CYP3A4/5 USING AN ENDOGENOUS BIOMARKER IN CHILDREN WITH DOWN SYNDROME [PDF]

Bulletin of Pharmaceutical Sciences. Assiut University, 2020
Background: Down syndrome (DS); a common chromosomal abnormality in humans can affect multiple organ systems. DS individuals usually use a wide range of medications.
Lateef Khan, Alaa Khedr, Fuad Almaweri, Jumana AlAama, Ahmed Ali, Zoheir Damanhouri   +5 more
doaj   +1 more source

Elevated 4β-hydroxycholesterol/cholesterol ratio in anorexia nervosa patients. [PDF]

Pharmacol Res Perspect, 2018
Recent studies have shown that the cytochrome P450 (CYP) 3A phenotype marker 4β‐hydroxycholesterol/cholesterol (4βOHC/C) ratio is negatively correlated with body weight in healthy volunteers, and that obese patients have lower 4βOHC levels than healthy ...
Hole K, Heiberg PL, Gjestad C, Mehus LL, Rø Ø, Molden E.   +5 more
europepmc   +2 more sources

4β-hydroxycholesterol as an endogenous CYP3A marker in cancer patients treated with taxanes. [PDF]

Br J Clin Pharmacol, 2015
Aim Taxanes are anti-cancer agents used to treat several types of solid tumours. They are metabolized by cytochrome P450 (CYP) 3A, displaying a large pharmacokinetic (PK) variability.
de Graan AJ, Sparreboom A, de Bruijn P, de Jonge E, van der Holt B, Wiemer EA, Verweij J, Mathijssen RH, van Schaik RH.   +8 more
europepmc   +2 more sources

Sensitive UHPLC-MS/MS quantification method for 4β- and 4α-hydroxycholesterol in plasma for accurate CYP3A phenotyping

Journal of Lipid Research, 2022
4β-Hydroxycholesterol (4β-OHC) is formed by Cytochrome P450 (CYP)3A and has drawn attention as an endogenous phenotyping probe for CYP3A activity. However, 4β-OHC is also increased by cholesterol autooxidation occurring in vitro due to dysregulated ...
Yosuke Suzuki, Ayako Oda, Jun Negami, Daiki Toyama, Ryota Tanaka, Hiroyuki Ono, Tadasuke Ando, Toshitaka Shin, Hiromitsu Mimata, Hiroki Itoh, Keiko Ohno   +10 more
doaj   +1 more source

Application of Virtual Twin PBPK Models in Individuals with Obesity via CYP3A4 Phenotyping Using Endogenous Biomarker Data. [PDF]

Clin Pharmacol Ther
Plasma 4β‐hydroxycholesterol (4β‐OHC) normalized for the levels of its parent cholesterol (4β‐OHC/C) is an endogenous biomarker for hepatic CYP3A4. This study evaluated CYP3A4 activity longitudinally in individuals while their obesity status was changing. 4β‐OHC/C was measured pre‐surgery (n = 54) and 2 years after Roux‐en‐Y gastric bypass (n = 30) and
Izat N, Kangne H, Jansson-Löfmark R, Hertel JK, Rostami-Hodjegan A, Robertsen I, Galetin A.   +6 more
europepmc   +2 more sources

Correlations between 4β-hydroxycholesterol and hepatic and intestinal CYP3A4: protein expression, microsomal ex vivo activity, and in vivo activity in patients with a wide body weight range. [PDF]

Eur J Clin Pharmacol, 2022
PURPOSE: Variability in cytochrome P450 3A4 (CYP3A4) metabolism is mainly caused by non-genetic factors, hence providing a need for accurate phenotype biomarkers.
Eide Kvitne K, Hole K, Krogstad V, Wollmann BM, Wegler C, Johnson LK, Hertel JK, Artursson P, Karlsson C, Andersson S, Andersson TB, Sandbu R, Hjelmesæth J, Skovlund E, Christensen H, Jansson-Löfmark R, Åsberg A, Molden E, Robertsen I.   +18 more
europepmc   +2 more sources

Pretransplant 4β-hydroxycholesterol does not predict tacrolimus exposure or dose requirements during the first days after kidney transplantation. [PDF]

Br J Clin Pharmacol, 2017
The CYP3A metric 4β-hydroxycholesterol (4βOHC) has been shown to correlate with tacrolimus steady-state apparent oral clearance (CL/F). Recently, pretransplant 4βOHC was shown not to predict tacrolimus CL/F after transplantation in a cohort of renal ...
Vanhove T, Hasan M, Annaert P, Oswald S, Kuypers DRJ.   +4 more
europepmc   +2 more sources