Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
1.
Cancer Med ; 12(15): 15983-15997, 2023 08.
Article in English | MEDLINE | ID: mdl-37334877

ABSTRACT

OBJECTIVE: To date, no direct comparisons have compared the effectiveness of all ALK inhibitors (ALKis) against ALK-positive non-small cell lung cancer (NSCLC). The aim of the present study was to investigate the efficacy and safety of ALKis in ALK-positive NSCLC. METHODS: The effectiveness of ALKis was evaluated by assessing progression-free survival (PFS), overall survival (OS), overall response rate (ORR), and PFS with baseline brain metastasis (BM). The serious adverse events (SAEs: Grade ≥ 3) and adverse events (AEs) leading to discontinuation were pooled to evaluate safety. We conducted an indirect treatment comparison between all ALKis by using a Bayesian model. RESULTS: Twelve eligible trials including seven treatments were identified. All of the ALKis improved PFS and ORR relative to chemotherapy. Consistent with alectinib, brigatinib, lorlatinib, and ensartinib showed significant differences versus crizotinib and ceritinib. Lorlatinib seemed to prolong PFS compared with alectinib (0.64, 0.37 to 1.07), brigatinib (0.56, 0.3 to 1.05), and ensartinib (0.53, 0.28 to 1.02). No significant difference was found among them in OS except for alectinib versus crizotinib. Moreover, alectinib was significantly more effective than crizotinib (1.54, 1.02 to 2.5) in achieving the best ORR. Subgroup analyses based on BM indicated that PFS was dramatically lengthened by lorlatinib. Compared with other ALKis, alectinib notably reduced the rate of SAEs. There was no striking difference between discontinuation for AEs, except for ceritinib versus crizotinib. The ranking of validity showed that lorlatinib had the longest PFS (98.32%) and PFS with BM (85.84%) and the highest ORR (77.01%). The rank of probabilities showed that alectinib had the potentially best safety in terms of SAEs (97.85%), and ceritinib had less discontinuation (95.45%). CONCLUSION: Alectinib was the first choice for patients with ALK-positive NSCLC and even for those with BM, whereas lorlatinib was the second choice. Long-term follow-up and prospective studies are warranted to compare ALKis and to verify our conclusions directly.


Subject(s)
Brain Neoplasms , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Crizotinib/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Network Meta-Analysis , Bayes Theorem , Anaplastic Lymphoma Kinase/genetics , Protein Kinase Inhibitors/adverse effects , Brain Neoplasms/secondary , Carbazoles/therapeutic use
2.
J Colloid Interface Sci ; 608(Pt 1): 720-734, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34628328

ABSTRACT

HYPOTHESIS: Alkyltrimethoxysilane (ATMS) is among most widely used silane coupling agents. These commercially available, reasonably priced chemicals are often utilized to improve the compatibility of inorganic surfaces with organic coatings. With three hydrolysable moieties, ATMS is an outstanding candidate for solving the hydrophilicity, moisture sensitivity and high cost of silica aerogels. However, ATMS has a non-hydrolysable alkyl chain that undergoes cyclization reactions. The alkyl chain prevents ATMS from being incorporated in aerogel structures. Polyvinyltrimethoxysilane (PVTMS) is a silica precursor that offers two types of crosslinking to the final aerogel product. This strong doubly-crosslinked network can potentially suppress the cyclization reactions of ATMS and include it in aerogel structure. EXPERIMENTS: PVTMS was used with ATMS having different alkyl lengths (3-16 carbons) and loadings (25 or 50 wt%) as the silica precursors. Acid and base catalysts were used to perform hydrolysis and condensation reactions on the mixture and ATMS:PVTMS aerogels were obtained via supercritical drying. FINDINGS: The incorporation of ATMS in the aerogels was approved by different characterization methods. Results showed that ATMS:PVTMS aerogels possess hydrophobicity (θ âˆ¼ 130°), moisture resistance, varying surface area (44-916 m2·g-1), meso/microporous structure and thermal insulation properties (λ âˆ¼ 0.03 W·m-1K-1). These samples also showed excellent performance in oil and organic solvent adsorption.


Subject(s)
Silicon Dioxide , Adsorption , Gels , Hydrophobic and Hydrophilic Interactions , Solvents
5.
Psychiatr Danub ; 32(1): 46-54, 2020.
Article in English | MEDLINE | ID: mdl-32303029

ABSTRACT

BACKGROUND: Patients with schizophrenia exhibit a higher mortality rate compared with the general population. This mortality has been attributed predominantly by the high risk of type 2 diabetes mellitus in the patients. We aimed to assess the inherent risk of glucose metabolism abnormalities in first-episode drug-naive schizophrenia. SUBJECTS AND METHODS: We searched English database (PubMed, EMBASE, MEDLINE, Cochrane Library databases) and Chinese database (Wan Fang Data, CBM disc, VIP, and CNKI) from their inception until Jul 2018 for case-control studies examining glucose metabolism abnormalities. Measurements, such as fasting plasma glucose levels, fasting plasma insulin levels, insulin resistance and HbA1c levels in first-episode antipsychotic-naive patients were used to test for prediabetes. Standardized/weighted mean differences and 95% confidence intervals were calculated and analyzed. RESULTS: 19 studies (13 in English and 6 in Chinese) consisting of 1065 patients and 873 controls were included. Fasting plasma glucose levels (95% CI; 0.02 to 0.29; P=0.03), 2 h plasma glucose levels after an OGTT (95% CI; 0.63 to 1.2; P<0.00001), fasting plasma insulin levels (95% CI; 0.33 to 0.73; P<0.00001), insulin resistance (95% CI; 0.29 to 0.6; P<0.00001) in patients with first-episode schizophrenia were significant elevated. There was no significant difference in HbA1c level (95% CI; -0.34 to 0.18; P=0.54) in patients with first-episode schizophrenia compared with controls. CONCLUSIONS: This meta-analysis showed that glucose metabolism was impaired in patients with first-episode schizophrenia. Higher quality studies with larger samples are warranted to confirm these findings.


Subject(s)
Glucose/metabolism , Schizophrenia/metabolism , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/metabolism , Humans , Insulin/blood , Insulin/metabolism , Schizophrenia/blood , Schizophrenia/complications , Schizophrenia/drug therapy
6.
EMBO Rep ; 20(9): e47892, 2019 09.
Article in English | MEDLINE | ID: mdl-31318145

ABSTRACT

The conversion of skeletal muscle fiber from fast twitch to slow-twitch is important for sustained and tonic contractile events, maintenance of energy homeostasis, and the alleviation of fatigue. Skeletal muscle remodeling is effectively induced by endurance or aerobic exercise, which also generates several tricarboxylic acid (TCA) cycle intermediates, including succinate. However, whether succinate regulates muscle fiber-type transitions remains unclear. Here, we found that dietary succinate supplementation increased endurance exercise ability, myosin heavy chain I expression, aerobic enzyme activity, oxygen consumption, and mitochondrial biogenesis in mouse skeletal muscle. By contrast, succinate decreased lactate dehydrogenase activity, lactate production, and myosin heavy chain IIb expression. Further, by using pharmacological or genetic loss-of-function models generated by phospholipase Cß antagonists, SUNCR1 global knockout, or SUNCR1 gastrocnemius-specific knockdown, we found that the effects of succinate on skeletal muscle fiber-type remodeling are mediated by SUNCR1 and its downstream calcium/NFAT signaling pathway. In summary, our results demonstrate succinate induces transition of skeletal muscle fiber via SUNCR1 signaling pathway. These findings suggest the potential beneficial use of succinate-based compounds in both athletic and sedentary populations.


Subject(s)
Muscle Fibers, Skeletal/drug effects , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/metabolism , Succinic Acid/pharmacology , Animals , Citric Acid Cycle/drug effects , Male , Mice , Mice, Inbred C57BL , Muscle Contraction/drug effects , Muscle Fatigue/drug effects , Muscle, Skeletal/drug effects , Myosin Heavy Chains/metabolism , Oxygen Consumption/drug effects , Signal Transduction/drug effects
7.
Mol Med Rep ; 16(5): 7361-7366, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28944867

ABSTRACT

It is well known that endurance training is effective to attenuate skeletal muscle atrophy. Succinate is a typical TCA metabolite, of which exercise could dramatically increase the content. The present study aimed to investigate the effect of succinate on protein synthesis in skeletal muscle, and try to delineate the underlying mechanism. The in vitro study revealed that succinate dose­dependently increased protein synthesis in C2C12 myotube along with the enhancement of phosphorylation levels of AKT Serine/Threonine Kinase 1(Akt), mammalian target of rapamycin, S6, eukaryotic translation initiation factor 4E, 4E binding protein 1 and forkhead box O (FoxO) 3a. Furthermore, it was demonstrated that 20 mM succinate markedly increased [Ca2+]i. Then, the phospho­extracellular regulated kinase (Erk), ­Akt level and the crosstalk between Erk and Akt were elevated in response to succinate. Notably, the Erk antagonist (U0126) or mTOR inhibitor (rapamycin) abolished the effect of succinate on protein synthesis. The in vivo study verified that succinate dose­dependently increased the protein synthesis, in addition to phosphorylation levels of Erk, Akt and FoxO3a in gastrocnemius muscle. In summary, these findings demonstrated that succinate promoted skeletal muscle protein deposition via Erk/Akt signaling pathway.


Subject(s)
MAP Kinase Signaling System/drug effects , Protein Biosynthesis/drug effects , Succinic Acid/pharmacology , Animals , Butadienes/pharmacology , Calcium/analysis , Cell Line , Forkhead Transcription Factors/metabolism , Immunoprecipitation , Male , Mice , Mice, Inbred C57BL , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/antagonists & inhibitors , Mitogen-Activated Protein Kinase 3/metabolism , Muscle, Skeletal/cytology , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Nitriles/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Sirolimus/pharmacology , TOR Serine-Threonine Kinases/metabolism
8.
Chem Biol Interact ; 264: 10-15, 2017 Feb 25.
Article in English | MEDLINE | ID: mdl-28087463

ABSTRACT

Cytochrome P450 2D6 (CYP2D6) is an important member of the cytochrome P450 enzyme superfamily. We recently identified 22 novel variants in the Chinese population using PCR and bidirectional sequencing methods. The aim of this study is to characterize the enzymatic activity of these variants and their effects on the metabolism of the antimuscarinic drug tolterodine in vitro. A baculovirus-mediated expression system was used to express wild-type CYP2D6 and 24 variants (CYP2D6*2, CYP2D6*10, and 22 novel CYP2D6 variants) at high levels. The insect microsomes expressing CYP2D6 proteins were incubated with 0.1-50 µM tolterodine at 37 °C for 30 min and the metabolites were analyzed by high-performance liquid chromatography-tandem mass spectrometry system. Of the 24 CYP2D6 variants tested, 2 variants (CYP2D6*92 and CYP2D6*96) were found to be catalytically inactive, 4 variants (CYP2D6*94, F164L, F219S and D336N) exhibited markedly increased intrinsic clearance values (Vmax/Km) compared with the wild-type (from 66.34 to 99.79%), whereas 4 variants (CYP2D6*10, *93, *95 and E215K) exhibited significantly decreased values (from 49.02 to 98.50%). This is the first report of all these rare alleles for tolterodine metabolism and these findings suggest that more attention should be paid to subjects carrying these infrequent CYP2D6 alleles when administering tolterodine in the clinic.


Subject(s)
Cytochrome P-450 CYP2D6/genetics , Cytochrome P-450 CYP2D6/metabolism , Muscarinic Antagonists/metabolism , Polymorphism, Genetic , Tolterodine Tartrate/metabolism , Alleles , Animals , Asian People/genetics , China , Cytochrome P-450 CYP2D6/chemistry , Humans , Insecta , Microsomes/metabolism , Models, Molecular
9.
Eur J Drug Metab Pharmacokinet ; 42(2): 261-268, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27207674

ABSTRACT

BACKGROUND AND OBJECTIVES: Atomoxetine is the first non-stimulant drug to be approved for the treatment of ADHD, while the effect of myricetin on the pharmacokinetic of atomoxetine in rats or human is still unknown. The present work was to study the impact of myricetin on the metabolism of atomoxetine both in vivo and in vitro. METHODS: Twenty healthy male Sprague-Dawley rats were randomly divided into four groups: A (control group), B (100 mg/kg myricetin), C (50 mg/kg myricetin), and D (25 mg/kg myricetin). A single dose of atomoxetine (10 mg/kg) was administrated half an hour later. In addition, human and rat liver microsomes were performed to determine the effect of myricetin on the metabolism of atomoxetine in vitro. RESULTS: Group B, C, D all increased the C max and AUC of atomoxetine, but decreased the C max and AUC of 4-hydroxyatomoxetine. Moreover, myricetin showed inhibitory effect on human and rat microsomes, the IC50 of myricetin was 8.651 and 35.45 µmol/L, respectively. CONCLUSIONS: Our study showed that myricetin could significantly inhibit the formation of atomoxetine metabolite both in vivo and in vitro. It is recommended that the effect of myricetin on the metabolism of atomoxetine should be noted and atomoxetine plasma concentration should be monitored.


Subject(s)
Atomoxetine Hydrochloride/pharmacokinetics , Flavonoids/pharmacology , Microsomes, Liver/metabolism , Phenols/pharmacokinetics , Propylamines/pharmacokinetics , Adrenergic Uptake Inhibitors/administration & dosage , Adrenergic Uptake Inhibitors/pharmacology , Animals , Area Under Curve , Atomoxetine Hydrochloride/administration & dosage , Dose-Response Relationship, Drug , Drug Interactions , Flavonoids/administration & dosage , Humans , Inhibitory Concentration 50 , Male , Rats , Rats, Sprague-Dawley
10.
Pharmacology ; 98(3-4): 124-33, 2016.
Article in English | MEDLINE | ID: mdl-27251229

ABSTRACT

The objective of this study was to assess the catalytic activity of 22 novel CYP2D6 allelic variants (2D6*87-*98, R25Q, F164L, E215K, F219S, V327M, D336N, V342M, R344Q, R440C and R497C) to olanzapine in vitro. Their protein products expressed in Spodoptera frugiperda 21 (Sf21) insect cells were incubated with olanzapine 100-2,000 µmol/l for 30 min. The kinetic parameters of Km, Vmax and intrinsic clearance were determined by 2-hydroxymethylolanzapine, the metabolite of olanzapine mediated by CYP2D6, using ultra-performance liquid chromatography tandem mass spectrometry. Results showed that the kinetic parameters of 2 alleles, CYP2D6*92 and 2D6*96, could not be detected; 17 allelic variants, CYP2D6*87-*88, 2D6*90-*91, 2D6*93-*95, 2D6*97, R25Q, F164L, E215K, F219S, V327M, V342M, R344Q, R440C and R497C, significantly reduced the intrinsic clearance of olanzapine; 2 variants, CYP2D6*89 and 2D6*98, increased the intrinsic clearance of olanzapine; no difference was found in intrinsic clearance of D336N. Furthermore, 6 alleles, CYP2D6*87, 2D6*88, 2D6*91, 2D6*93, 2D6*97 and R497C, exhibited higher Km values in a range of 120.80-217.56% relative to wild-type CYP2D6*1. The research demonstrated the metabolic phenotype of the 22 novel CYP2D6 variants for olanzapine that were different from probe drugs we used previously and might provide beneficial information to the personalized medicine of olanzapine.


Subject(s)
Antipsychotic Agents/metabolism , Asian People/genetics , Benzodiazepines/metabolism , Cytochrome P-450 CYP2D6/genetics , Genetic Variation/genetics , Population Surveillance , Dose-Response Relationship, Drug , Humans , Olanzapine , Polymorphism, Genetic/genetics , Population Surveillance/methods
11.
Can J Physiol Pharmacol ; 94(8): 895-9, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27203132

ABSTRACT

Cytochrome P450 enzyme 2D6 (CYP2D6) is an important member of the cytochrome P450 enzyme superfamily, with more than 100 CYP2D6 allelic variants being previously reported. The aim of this study was to assess the catalytic characteristics of 25 alleles (CYP2D6.1 and 24 CYP2D6 variants) and their effects on the metabolism of propafenone in vitro. Twenty-five CYP2D6 alleles were expressing in 21 Spodoptera frugiperda (Sf) insect cells, and each variant was evaluated using propafenone as the substrate. Reactions were performed at 37 °C with 1-100 µmol/L propafenone for 30 min. After termination, the product 5-OH-propafenone was extracted and used for signal collection by ultra-performance liquid chromatography (UPLC). Compared with wild type CYP2D6.1, the intrinsic clearance (Vmax and Km) values of all variants were significantly altered. Three variants (CYP2D6.87, CYP2D6.90, CYP2D6.F219S) exhibited markedly increased intrinsic clearance values (129% to 165%), whereas 21 variants exhibited significantly decreased values (16% to 85%) due to increased Km and (or) decreased Vmax values. These results indicated that the majority of tested alleles had significantly altered catalytic activity towards propafenone hydroxylation in this expression system. Attention should be paid to subjects carrying these rare alleles when treated with propafenone.


Subject(s)
Alleles , Anti-Arrhythmia Agents/metabolism , Asian People/genetics , Cytochrome P-450 CYP2D6/genetics , Pharmacogenomic Variants/genetics , Propafenone/metabolism , Animals , Humans , Insecta , Microsomes/metabolism
12.
Pharm Biol ; 54(11): 2475-2479, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27097346

ABSTRACT

CONTEXT: Amitriptyline (AT), one of the tricyclic antidepressants, is still widely used for the treatment of the depression and control of anxiety states and panic disorders in the developing countries. OBJECTIVE: This study evaluates the catalytic activities of CYP2D6*1, CYP2D6*2, CYP2D6*10 and 22 novel alleles in Han Chinese population and their effects on the N-demethylation of AT in vitro. MATERIALS AND METHODS: CYP2D6*1 and 24 CYP2D6 allelic variants were highly expressed in insect cells, and all variants were characterized using AT as a substrate. Reactions were performed at 37 °C with 10-1000 µM substrate for 30 min. We established a HPLC method to quantify the levels of nortriptyline (NT). The kinetic parameters Km, Vmax and intrinsic clearance (Vmax/Km) of NT were calculated. RESULTS: Among the 24 CYP2D6 variants, all variants exhibited decreased intrinsic clearance values compared with wild-type CYP2D6.1. Kinetic parameters of two CYP2D6 variants (CYP2D6*92, *96) could not be determined because of absent enzyme activities. CONCLUSIONS: The comprehensive in vitro assessment of CYP2D6 variants provides significant insight into allele-specific activity towards AT in vivo.


Subject(s)
Amitriptyline/metabolism , Antidepressive Agents, Tricyclic/metabolism , Cytochrome P-450 CYP2D6/genetics , Alleles , Asian People , China/ethnology , Chromatography, High Pressure Liquid , Cytochrome P-450 CYP2D6/physiology , Dealkylation , Genetic Variation , Humans
13.
J Pharm Pharmacol ; 68(6): 819-25, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27109434

ABSTRACT

OBJECTIVES: This study aimed to assess the catalytic characteristics of 24 CYP2D6 allelic isoforms found in Chinese Han population on the metabolism of tamoxifen in vitro. METHODS: Recombinant CYP2D6 microsomes of distinguished genotypes were used to characterize the corresponding enzyme activity towards tamoxifen. About 5-2500 µm tamoxifen was incubated for 30 min at 37 °C. Using high-performance liquid chromatography to detect the products, the kinetic parameters Km , Vmax and intrinsic clearance (Vmax /Km ) of N-desmethyltamoxifen were determined. KEY FINDINGS: Of the 24 tested allelic variants, the differences of intrinsic clearance value were shown as follows: CYP2D6.89 was much higher than wild-type CYP2D6.1, 2 allelic isoforms (CYP2D6.88 and D336N) exhibited similar intrinsic clearance values as the wild-type enzyme, two variants displayed weak or no activity, while the rest 19 variants showed significantly reduced intrinsic clearance values ranging from 7.46 to 81.11%. CONCLUSION: The comprehensive assessment of CYP2D6 variants provides significant insights into allele-specific activity towards tamoxifen in vitro, suggesting that most of the carriers of these alleles might be paid more attention when using CYP2D6-mediated drugs clinically.


Subject(s)
Cytochrome P-450 CYP2D6/metabolism , Pharmacogenomic Variants , Asian People/genetics , Biotransformation , Catalysis , Chromatography, High Pressure Liquid , Cytochrome P-450 CYP2D6/genetics , Dealkylation , Genotype , Humans , Kinetics , Microsomes/enzymology , Phenotype , Recombinant Proteins/metabolism , Substrate Specificity , Tamoxifen/analogs & derivatives , Tamoxifen/metabolism
14.
Xenobiotica ; 46(5): 439-44, 2016.
Article in English | MEDLINE | ID: mdl-26391142

ABSTRACT

1. The objective of this study were to investigate the effect of orally administered resveratrol on the pharmacokinetics of aripiprazole (APZ) in rat, and the inhibitory effects of resveratrol on APZ dehydrogenation activity in liver microsomes and human cytochrome P450 3A4 and 2D6. 2. Twenty-five healthy male Sprague-Dawley rats were randomly divided into five groups: A (control group), B (multiple dose of 200 mg/kg resveratrol), C (multiple dose of 100 mg/kg resveratrol), D (a single dose of 200 mg/kg resveratrol) and E (a single dose of 100 mg/kg resveratrol). A single dose of 3 mg/kg APZ administered orally 30 min after administration of resveratrol. In addition, CYP2D6*1, CYP3A4*1, human and rat liver microsomes were performed to determine the effect of resveratrol on the metabolism of APZ in vitro. 3. The multiple dose of 200 or 100 mg/kg resveratrol significantly increased the AUC and Cmax of APZ. The resveratrol also obviously decreased the CL, but without any significant difference on t1/2 in vivo. On the other hand, resveratrol showed inhibitory effect on CYP3A4*1, CYP2D6*1, human and rat microsomes, the IC50 of resveratrol was 6.771, 87.87, 45.11 and 35.59 µmol l(-1), respectively. 4. Those results indicated more attention should be paid when APZ was administrated combined with resveratrol.


Subject(s)
Aripiprazole/pharmacokinetics , Cytochrome P-450 CYP2D6/metabolism , Cytochrome P-450 CYP3A/metabolism , Drug Interactions , Microsomes, Liver/drug effects , Stilbenes/pharmacokinetics , Animals , Antipsychotic Agents/pharmacokinetics , Area Under Curve , Chromatography, Liquid , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacokinetics , Humans , Inhibitory Concentration 50 , Male , Microsomes, Liver/metabolism , Rats , Rats, Sprague-Dawley , Resveratrol , Tandem Mass Spectrometry
15.
Xenobiotica ; 46(5): 424-9, 2016.
Article in English | MEDLINE | ID: mdl-26406933

ABSTRACT

1. CYP2D6 is an important member of the cytochrome P450 (CYP450) enzyme superfamily, we recently identified 22 CYP2D6 alleles in the Han Chinese population. The aim of this study was to assess the catalytic activities of these allelic isoforms and their effects on the metabolism of venlafaxine in vitro. 2. The wild-type and 24 CYP2D6 variants were expressed in insect cells, and each variant was characterized using venlafaxine as the substrate. Reactions were performed at 37 °C with 5-500 µM substrate (three variants was adjusted to 1000 µM) for 50 min. By using high-performance liquid chromatography to detect the products, the kinetic parameters Km, Vmax, and intrinsic clearance (Vmax/Km) of O-desmethylvenlafaxine were determined. 3. Among the 22 CYP2D6 variants, the intrinsic clearance (Vmax/Km) values of all variants were significantly decreased (from 0.2% to 84.5%) compared with wild-type CYP2D6*1. In addition, the kinetic parameters of two CYP2D6 variants could not be detected because they have no detectable enzyme activity. 4. The comprehensive in vitro assessment of CYP2D6 variants provides significant insights into allele-specific activity towards venlafaxine in vivo.


Subject(s)
Cytochrome P-450 CYP2D6/genetics , Genetic Variation , Venlafaxine Hydrochloride/metabolism , Alleles , Animals , Catalysis , Cells, Cultured , China , Chromatography, High Pressure Liquid , Desvenlafaxine Succinate/chemistry , Dose-Response Relationship, Drug , Humans , Insecta/cytology , Microsomes/enzymology , Pharmacogenetics , Polymorphism, Genetic , Protein Isoforms , Temperature , Venlafaxine Hydrochloride/administration & dosage
16.
Pharmacology ; 97(1-2): 78-83, 2016.
Article in English | MEDLINE | ID: mdl-26666748

ABSTRACT

OBJECTIVE: The aim of this article was to assess the catalytic activities of 24 cytochrome P450 2D6 (CYP2D6) variants found in the Chinese population toward atomoxetine in vitro as well as CYP2D6.1. METHODS: In this study, the co-expression enzyme of human recombinant CYPOR, CYPb5, and CYP2D6.1 or other CYP2D6 variants with the baculovirus-mediated insect cells (Sf21) was used to study the catalytic activities of 24 CYP2D6 variants toward atomoxetine metabolism. The metabolite of atomoxetine (4-hydroxyatomoxetine) was detected by ultra-high performance liquid chromatography-mass spectrometry method. RESULTS: The intrinsic clearance (Vmax/Km) values of most variants were significantly altered when compared with CYP2D6.1. CYP2D6.94, CYP2D6.D336N, CYP2D6.R440C exhibited marked increased values 172, 126, 121% respectively. CYP2D6.89 and CYP2D6.98 exhibited similar catalytic activity as the wild type, whereas 17 variants exhibited significantly decreased values (from 5 to 87%) due to increase Km and/or decrease Vmax values. However, CYP2D6.92 and CYP2D6.96 showed no or few activity because of producing nothing. CONCLUSIONS: Our results suggest that most of these newly found variants exhibit significantly changed catalytic activities compared with the wild type. And these findings provide valuable information for the growth and development of personalized medicine in China.


Subject(s)
Atomoxetine Hydrochloride/pharmacokinetics , Cytochrome P-450 CYP2D6/genetics , Animals , Asian People , China , Chromatography, High Pressure Liquid , Genotype , Humans , Mass Spectrometry , Phenols/metabolism , Propylamines/metabolism , Sf9 Cells
17.
Eur J Drug Metab Pharmacokinet ; 41(6): 759-765, 2016 Dec.
Article in English | MEDLINE | ID: mdl-26542054

ABSTRACT

BACKGROUND AND OBJECTIVES: Hemangeol, approved for the treatment of proliferative infantile hemangiomas requiring systemic therapy, is metabolized by cytochrome P450 2D6 (CYP2D6), which is a highly polymorphic enzyme that metabolizes a large number of drugs. More than 100 CYP2D6 allelic variants have been reported so far, including 22 novel variants that discovered in our lab in the Chinese population. Our study aimed to probe the enzymatic activity of these variants toward hemangeol in vitro with recombinant microsomes that expressed in sf21 insect cells using a baculovirus-mediated expression system. METHODS: The wild-type CYP2D6.1 and other variants (CYP2D6.2, CYP2D6.10 and 22 novel CYP2D6 variants) were incubated with 1-200 µM hemangeol for 50 min at 37 °C. Then the products were extracted, and signal detection was performed by high-performance liquid chromatography with fluorescence detector. RESULTS: All of the variants exhibited changed apparent Michaelis-Menten constant (Km) or maximum velocity of the reaction (V max) values compared with that of wild-type protein. The intrinsic clearances (V max /Km) were significantly decreased by 0.37 to 42.74 %. However, CYP2D6.92 and CYP2D6.96 showed no or minimal enzymatic activity as no concentration of 4'-hydroxypropranolol was detected. CONCLUSIONS: The comprehensive in vitro assessment of CYP2D6 variants provides significant insights into allele-specific activity towards hemangeol in vivo.


Subject(s)
Adrenergic beta-Antagonists/metabolism , Angiogenesis Inhibitors/metabolism , Cytochrome P-450 CYP2D6/genetics , Mutation , Polymorphism, Genetic , Propranolol/metabolism , Vasodilator Agents/metabolism , Alleles , Animals , Asian People , Biocatalysis , Biotransformation , China , Cytochrome P-450 CYP2D6/metabolism , Genetic Association Studies , Humans , Hydroxylation , Microsomes/enzymology , Microsomes/metabolism , Polymorphism, Single Nucleotide , Recombinant Proteins/metabolism , Sf9 Cells , Spodoptera , Substrate Specificity
18.
Pharmacology ; 96(3-4): 118-23, 2015.
Article in English | MEDLINE | ID: mdl-26202346

ABSTRACT

OBJECTIVE: This study was conducted to investigate the effects of orally administered apigenin on the pharmacokinetics of venlafaxine (VEN) in rats and on the metabolism of VEN in human and rat liver microsomes in vitro. METHODS: Ten healthy male SD rats were randomly divided into 2 groups: A group (control group), B group (a single dose of 250 mg/kg apigenin). A single dose of 20 mg/kg VEN was administered orally 30 min after administration of apigenin (250 mg/kg). VEN plasma levels were measured by HPLC with fluorescence detection, and pharmacokinetic parameters were calculated by DAS 3.0 software. RESULTS: The single dose of 250 mg/kg apigenin significantly increased the AUC0-t of VEN by 40.9% (p < 0.05) and obviously increased the peak plasma concentration (Cmax) of VEN (p < 0.05). Furthermore, apigenin showed inhibitory effect on human and rat microsomes and the IC50 of apigenin was 58.37 and 25.73 µmol/l, respectively. CONCLUSIONS: Our results indicated that an intake of apigenin could increase VEN plasma levels and some of its pharmacokinetic parameters (AUC, Tmax). Thus, more attention should be paid when VEN was administrated combined with apigenin.


Subject(s)
Antidepressive Agents, Second-Generation/pharmacokinetics , Apigenin/pharmacology , Venlafaxine Hydrochloride/pharmacokinetics , Animals , Area Under Curve , Drug Interactions , Half-Life , Humans , In Vitro Techniques , Male , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Rats , Rats, Sprague-Dawley , Venlafaxine Hydrochloride/antagonists & inhibitors
19.
Article in English | MEDLINE | ID: mdl-26094207

ABSTRACT

In this work, a simple, sensitive and fast ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantitative determination of vortioxetine in rat plasma. Plasma samples were processed with a protein precipitation. The separation was achieved by an Acquity UPLC BEH C18 column (2.1mm×50mm, 1.7µm) column with a gradient mobile phase consisting of 0.1% formic acid in water and acetonitrile. Detection was carried out using positive-ion electrospray tandem mass spectrometry via multiple reaction monitoring (MRM). The validated method had an excellent linearity in the range of 0.05-20ng/mL (R(2)>0.997) with a lower limit of quantification (0.05ng/mL). The extraction recovery was in the range of 78.3-88.4% for vortioxetine and 80.3% for carbamazepine (internal standard, IS). The intra- and inter-day precision was below 8.5% and accuracy was from -11.2% to 9.5%. No notable matrix effect and astaticism was observed for vortioxetine. The method has been successfully applied to a pharmacokinetic study of vortioxetine in rats for the first time, which provides the basis for the further development and application of vortioxetine.


Subject(s)
Chromatography, High Pressure Liquid/methods , Piperazines/blood , Piperazines/pharmacokinetics , Sulfides/blood , Sulfides/pharmacokinetics , Tandem Mass Spectrometry/methods , Animals , Linear Models , Male , Piperazines/chemistry , Rats , Rats, Sprague-Dawley , Reproducibility of Results , Sensitivity and Specificity , Sulfides/chemistry , Vortioxetine
20.
Drug Dev Ind Pharm ; 41(8): 1363-7, 2015.
Article in English | MEDLINE | ID: mdl-25144335

ABSTRACT

CYP2C9 is an important member of the cytochrome P450 enzyme superfamily, and 57 cytochrome P450 2C9 alleles have been previously reported. To examine the enzymatic activity of the CYP2C9 alleles, kinetic parameters for 4'-hydroxyflurbiprofen were determined using recombinant human P450s CYP2C9 microsomes from insect cells Sf21 carrying wild-type CYP2C9*1 and other variants. The results showed that the enzyme activity of most of the variants decreased comparing with the wild type as the previous studies reported, while the enzyme activity of some of them increased, which were not in accordance with the previous researches. Of the 36 tested CYP2C9 allelic isoforms, two variants (CYP2C9*53 and CYP2C9*56) showed a higher intrinsic clearance value than the wild-type protein, especially for CYP2C9*56, exhibited much higher intrinsic clearance (197.3%) relative to wild-type CYP2C9*1, while the remaining 33 CYP2C9 allelic isoforms exhibited significantly decreased clearance values (from 0.6 to 83.8%) compared to CYP2C9*1. This study provided the most comprehensive data on the enzymatic activities of all reported CYP2C9 variants in the Chinese population with regard to the commonly used non-steroidal anti-inflammatory drug, flurbiprofen (FP). The results indicated that most of the tested rare alleles decreased the catalytic activity of CYP2C9 variants toward FP hydroxylation in vitro. This is the first report of all these rare alleles for FP metabolism providing fundamental data for further clinical studies on CYP2C9 alleles for FP metabolism in vivo.


Subject(s)
Cytochrome P-450 CYP2C9/genetics , Cytochrome P-450 CYP2C9/metabolism , Flurbiprofen/metabolism , Polymorphism, Genetic/physiology , Animals , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Humans , Insecta
SELECTION OF CITATIONS
SEARCH DETAIL
...