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1.
Int J Oncol ; 53(2): 791-800, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29845233

ABSTRACT

Matrine, one of the main alkaloid components extracted from the traditional Chinese herb, Sophora flavescens Ait, has various pharmacological effects, and has been reported to exert antitumor activity in melanoma. In the current study, the molecular mechanisms underlying the inhibitory effects of matrine were investigated in melanoma cell line. It was initially confirmed that matrine inhibited proliferation, invasion and induced apoptosis in human A375 and SK-MEL-2 melanoma cell lines in vitro. Subsequently, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis demonstrated that the expression of microRNA (miR)-19b-3p was significantly increased in melanoma cells and was downregulated by treatment with matrine. Furthermore, downregulated miR-19b-3p exerted effects similar to 500 µg/ml matrine on cell proliferation, invasion and apoptosis. Phosphatase and tensin homolog (PTEN) mRNA was identified as a direct target of miR-19b-3p through bioinformatics analysis and a dual-luciferase reporter assay. Additionally, western blotting and RT-qPCR analysis demonstrated that the expression of PTEN protein and mRNA were increased by the treatment with matrine. Furthermore, silencing of PTEN expression reversed the effects of matrine and miR-19b-3p downregulation in A375 and SK-MEL-2 cells. Taken together, the results indicated that matrine may suppress cell proliferation and invasion and induce cell apoptosis partially via miR-19b-3p targeting of PTEN.


Subject(s)
Alkaloids/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Melanoma/genetics , MicroRNAs/genetics , PTEN Phosphohydrolase/genetics , Quinolizines/pharmacology , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Humans , Melanoma/metabolism , Neoplasm Invasiveness , PTEN Phosphohydrolase/metabolism , Matrines
2.
J Cell Biochem ; 119(4): 3440-3450, 2018 04.
Article in English | MEDLINE | ID: mdl-29143976

ABSTRACT

In performing our experiment, impaired autophagy increased hepatocellular damage during the reperfusion period. It was demonstrated by the effect of blocking autophagy using bafilomycin A1 or knocking Atg5 gene out reduces the anti-apoptotic effect of Stat3. Here we focus on the role of signal transducer and activator of transcription 3 (Stat3) in regulating autophagy to alleviate hepatic IRI. We found that Stat3 was up-regulated during hepatic IRI and was associated with an activation of the autophagic signaling pathway. This increased Stat3 expression, which was allied with high autophagic activity, alleviated liver damage to IR, an effect which was abrogated by Stat3 epletion as demonstrated in both in vivo and in vitro methods. The levels of Atg5 protein were decreased when Stat3 was inhibited by HO 3867 or siStat3. We conclude that Stat3 appeared to exert a pivotal role in hepatic IRI, by activating autophagy to alleviate hepatic IRI, and Atg5 was required for this process. The identification of this novel pathway, that links expression levels of Stat3 with Atg5-mediated autophagy, may provide new insights for the generation of novel protective therapies directed against hepatic IRI.


Subject(s)
Autophagy-Related Protein 5/metabolism , Autophagy/physiology , Liver/metabolism , Liver/pathology , STAT3 Transcription Factor/metabolism , Animals , Apoptosis/genetics , Apoptosis/physiology , Autophagy/genetics , Blotting, Western , Cell Line , Cell Survival/genetics , Cell Survival/physiology , Disease Models, Animal , Immunohistochemistry , Male , Mice , Mice, Inbred C57BL , Microscopy, Confocal , Microscopy, Electron, Transmission , Reperfusion Injury/genetics , Reperfusion Injury/metabolism , Signal Transduction/genetics , Signal Transduction/physiology
3.
Curr Drug Metab ; 17(7): 721-8, 2016.
Article in English | MEDLINE | ID: mdl-27174459

ABSTRACT

BACKGROUND: It was reported that phenytoin can prevent early post traumatic seizures. The present study aims to establish a population pharmacokinetic (PPK) model of oral phenytoin in patients with intracranial tumor during the early periods, the first week, of post-craniotomy to optimize phenytoin dosage regimen. METHODS: Sixty-two patients with intracranial tumor were genotyped for CYP2C9 and CYP2C19 by real time PCR (TaqMan probe), and subsequently their phenytoin dosage regimens were designed according to the results of previous literature. A total of 123 plasma concentrations of oral phenytoin during the early periods of post-craniotomy, patient demographics, clinical biochemical indicators and drug combination were collected. A PPK model was performed using the nonlinear mixed effects model (NONMEM) program. RESULTS: The final PPK model equations of oral phenytoin were found to be as follows: for patients with CYP2C9 *1/*1, Vmax=22.66.(BWT/60.96)0.454(mg/h) and Km; =4.03 (mg/L); for patients with CYP2C9*1/*3, Vmax = 16.65.(BWT / 60.96 )0.454(mg/h) and Km =5.96 (mg/L). The PPK model was proved to be stable and effective by bootstrap method. Clinical individualized dosage regimens of additional 50 patients were designed by above PPK model. Concentrations on the morning of Day 7 (D7 concentrations) of 56% (28/50) of these patients were within the therapeutic range (10.20mg/L), which demonstrated better improvement than that of 37.1% of above 62 patients. CONCLUSION: The final PPK model of oral phenytoin may be helpful to design phenytoin individualized dosage regimen at the early stage of post-craniotomy when characteristics of patients meet these of subpopulation in the study.


Subject(s)
Anticonvulsants/pharmacokinetics , Models, Biological , Neoplasms/metabolism , Phenytoin/pharmacokinetics , Adult , Aged , Anticonvulsants/blood , Anticonvulsants/therapeutic use , Asian People/genetics , Craniotomy , Cytochrome P-450 CYP2C19/genetics , Cytochrome P-450 CYP2C19/metabolism , Cytochrome P-450 CYP2C9/genetics , Cytochrome P-450 CYP2C9/metabolism , Female , Genotype , Humans , Male , Middle Aged , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/surgery , Phenytoin/blood , Phenytoin/therapeutic use , Postoperative Period , Seizures/genetics , Seizures/metabolism , Seizures/prevention & control , Young Adult
4.
Transl Lung Cancer Res ; 4(5): 598-604, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26629428

ABSTRACT

BACKGROUND: With the widespread use of general health examinations, the detection rate of pulmonary nodules has increased; however, locating the pulmonary nodules is still a challenge. METHODS: We reviewed cases that underwent computed tomography (CT)-guided coil localization followed by real-time digital subtraction angiography (DSA)-guided accurate resection of solitary pulmonary nodules (SPNs) using video-assisted thoracoscopic surgery (VATS) at our hospital, and we evaluated the clinical value. From September 2011 to October 2014, 116 cases with SPNs were treated in our unit. The lesion was preoperatively localized using coil placement under CT guidance, and the patients were subsequently transferred to the hybrid operating room. VATS wedge resection with real-time DSA guidance was performed, and further processing was conducted in accordance with the intraoperative pathological diagnosis for these lesions. RESULTS: Coil localization, which averaged 15.30±3.20 min, was successful in all patients (100%), while VATS wedge resection took 24.20±12.10 min and lobectomy or segmentectomy took 88.8±36 min. The pathological results revealed malignant lesions in 61 cases and benign lesions in 55 cases. CONCLUSIONS: Preoperative CT-guided coil localization for SPNs had a high accuracy with no serious complications. Following real-time DSA-guided VATS resection, the lesions could be accurately removed with a cutting edge distance of >2 cm to the lesion, which may help diagnose and treat the SPN simultaneously.

5.
J Ethnopharmacol ; 151(1): 287-91, 2014.
Article in English | MEDLINE | ID: mdl-24269776

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: San-Huang formula is a popular traditional Chinese medicine (TCM) preparation to replenish Qi, resolve phlegm, dissipate blood stasis, and therapy metabolic syndrome in China. Metabolic syndrome, which is accompanied by Qi and blood stasis, mainly arises from spleen deficiency in essence. There is limited information available for differences of pharmacokinetic properties of San-Huang formula between normal and metabolic syndrome rats. The present study was conducted to compare the pharmacokinetics of berberine as well as palmatine in normal and metabolic syndrome rats following oral administration of San-Huang formula extract. MATERIALS AND METHODS: The animals were orally administered with San-Huang formula extract with the equivalent dose of 60.4 and 12.5mg/kg for berberine and palmatine, respectively. The blood samples were collected according to the time schedule. The concentrations of berberine and palmatine in rat plasma were determined by LC-ESI/MS. Various pharmacokinetic parameters were estimated from the plasma concentration versus time data using non-compartmental methods. RESULTS: It was found that AUC0-t, Cmax, Vd and CL of berberine and palmatine in metabolic syndrome rats were significantly different (P<0.05) from normal rats. CONCLUSIONS: The results indicated that berberine and palmatine have higher uptake and slower elimination in the rats with metabolic syndrome, which suggests that the rate and extent of drug metabolism were altered in metabolic syndrome rats.


Subject(s)
Berberine Alkaloids/pharmacokinetics , Berberine/pharmacokinetics , Metabolic Syndrome/metabolism , Administration, Oral , Animals , Area Under Curve , Drugs, Chinese Herbal/chemistry , Half-Life , Male , Molecular Structure , Random Allocation , Rats
6.
Eur J Drug Metab Pharmacokinet ; 37(4): 271-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22446981

ABSTRACT

To set up a population pharmacokinetic (PPK) model of cyclosporine A (CsA) in Chinese allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients to provide reference for individualized medication in clinical practice. 281 trough plasma concentrations of CsA and covariates such as demographics, clinical laboratory values and coadministration were retrospectively collected from 73 allo-HSCT patients. Population modeling was performed using general model of NONMEM expressed by differential equation. Hematocrit (HCT), plasma albumin (ALB) level, and coadministration of itraconazole (ITR) were found to significantly affect the clearance of CsA (CL, L/h). The final model formula was: CL = 28.2 × [1 - 0.0263 × (HCT - 26.62)] × [1 - 0.0289 × (ALB - 37.63)] × [1 - 0.146 × ITR] (L/h); V = 1,080 (L); K (a) = 1.28 (h⁻¹); F = 0.711. The interindividual variabilities for CL, V and F were 21.4, 41.5 and 6.07 %, respectively. The residual error was 0.00422 mg/L. The PPK model was validated to be effective and stable by bootstrap method. Clinical applications showed there was a good linear correlation between the predicted concentrations and the observed (y = 1.0095x + 0.0082, r = 0.9309, p < 0.0001). The PPK final model of CsA in Chinese allo-HSCT patients can be established using the NONMEM program which can be applied in clinical allo-HSCT practice when characteristics of patients fit in with those of subpopulation in the study.


Subject(s)
Cyclosporine/pharmacokinetics , Hematopoietic Stem Cell Transplantation , Immunosuppressive Agents/pharmacokinetics , Adolescent , Adult , Asian People , Female , Humans , Itraconazole/pharmacology , Male , Middle Aged , Models, Biological , Retrospective Studies , Transplantation, Homologous
7.
Clin Chim Acta ; 413(7-8): 683-90, 2012 Apr 11.
Article in English | MEDLINE | ID: mdl-22227166

ABSTRACT

BACKGROUND: This study aimed to evaluate the effect of UGT1A8*2, SLCO1B3 T334G, ABCC2 C-24T and ABCG2 C421A polymorphisms on the pharmacokinetics (PKs) of mycophenolic acid (MPA) and its phenolic glucuronide (MPAG) in healthy Chinese volunteers and in stable renal transplant patients. METHODS: The data were extracted from comparative bioavailability studies conducted in 42 healthy individuals and 37 renal transplant patients. A complete PK profile was obtained over 48 h for healthy volunteers and over 12h for the transplant patients. The MPA/MPAG plasma concentrations were measured by HPLC. The genotypes were determined using either the Taqman probe technique or direct sequencing. A multivariate analysis was used to assess the effect of the genotypes (UGT1A8*2, SLCO1B3 T334G, ABCC2 C-24T and ABCG2 C421A) and other covariates (age, weight, height, calculated creatinine clearance, serum albumin, haemoglobin and drug comedication) on the AUC(4-12) and AUC(0-12) for MPA and MPAG in the healthy volunteers and patients. RESULTS: In the healthy volunteers, the dose-adjusted geometric means (GM) of the MPA AUC(4-12) in individuals with the SLCO1B3 334T allele were 30.4% lower than those values in the 334G homozygote carriers (P<0.05); in the transplant patients, the steroid dose was associated with a negative effect on the AUC of MPAG (P<0.03) and weight was associated with a negative effect on the AUC for MPA in the healthy volunteers and patients (P<0.03). No other significant effect of genotype or of the other studied variables on AUC(4-12) or AUC(0-12) of MPA/MPAG was found in the healthy volunteers or patients. CONCLUSIONS: The PKs of MPA is affected by the SLCO1B3 polymorphism in healthy Chinese individuals. The absence of an effect of SLCO1B3 polymorphisms in transplant patients may be due to the co-administration of cyclosporine (CsA). Concomitant steroid dose and weight are two important covariates of the AUC of MPA and MPAG, which should be taken into account in clinical use. Further confirmatory in vivo studies are needed.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Glucuronides/pharmacokinetics , Glucuronosyltransferase/genetics , Immunosuppressive Agents/pharmacokinetics , Multidrug Resistance-Associated Proteins/genetics , Mycophenolic Acid/pharmacokinetics , Neoplasm Proteins/genetics , Organic Anion Transporters, Sodium-Independent/genetics , Polymorphism, Single Nucleotide , ATP Binding Cassette Transporter, Subfamily G, Member 2 , Area Under Curve , Base Sequence , Case-Control Studies , China , DNA Primers , Female , Humans , Male , Multidrug Resistance-Associated Protein 2 , Reverse Transcriptase Polymerase Chain Reaction , Solute Carrier Organic Anion Transporter Family Member 1B3
8.
J Agric Food Chem ; 59(11): 6312-8, 2011 Jun 08.
Article in English | MEDLINE | ID: mdl-21524054

ABSTRACT

Ginsenoside Rb1, a known phytoestrogen, is a major pharmacologically active component in ginseng. The present study was designed to investigate the effect of ginsenoside Rb1 on fetal bovine serum (FBS)-induced proliferation and tumor necrosis factor-α (TNF-α)-evoked inflammatory responses in cultured rat aortic vascular smooth muscle cells (VSMCs). The data showed that Rb1 potently inhibited VSMC proliferation and cell growth induced by 5% FBS. These inhibitory effects were associated with G(1) cell cycle arrest and down-regulation of cell cycle proteins. Treatment with Rb1 reduced FBS-induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. Furthermore, TNF-α-evoked inflammatory responses were inhibited by Rb1. Reporter gene assay indicated that Rb1 could transactivate ERß especially. Moreover, Rb1-mediated inhibition of VSMCs proliferation was greatly blocked by transfection of ERß siRNA. These results suggest that Rb1 inhibits FBS-induced proliferation and TNF-α-evoked inflammatory responses in VSMCs. The findings presented here highlight the possible therapeutic use of Rb1 in cardiovascular disease.


Subject(s)
Aorta/cytology , Cell Proliferation/drug effects , Down-Regulation/drug effects , Ginsenosides/pharmacology , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/immunology , Plant Extracts/pharmacology , Animals , Aorta/drug effects , Aorta/immunology , Cell Cycle/drug effects , Cells, Cultured , Female , Myocytes, Smooth Muscle/cytology , Rats , Rats, Sprague-Dawley
9.
Acta Pharmacol Sin ; 31(6): 753-8, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20523346

ABSTRACT

AIM: To establish a population pharmacokinetic (PPK) model of digoxin in older Chinese patients to provide a reference for individual medication in clinical practice. METHODS: Serum concentrations of digoxin and clinically related data including gender, age, weight (WT), serum creatinine (Cr), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), albumin (ALB), and co-administration were retrospectively collected from 119 older patients taking digoxin orally for more than 7 d. NONMEM software was used to get PPK parameter values, to set up a final model, and to assess the models in clinical practice. RESULTS: Spironolactone (SPI), WT, and Cr markedly affected the clearance rate of digoxin. The final model formula is Cl/F=5.9x[1-0.412 x SPI] x [1-0.0101x(WT-62.9)] x [1-0.0012x(Cr-126.8)] (L/h); Ka=1.63 (h(-1)); V(d)/F=550 (L). The population estimates for Cl/F and V(d)/F were 5.9 L/h and 550 L, respectively. The interindividual variabilities (CV) were 49.0% for Cl/F and 94.3% for V(d)/F. The residual variability (SD) between observed and predicted concentrations was 0.365 microg/L. The difference between the objective function value and the primitive function value was less than 3.84 (P>0.05) by intra-validation. Clinical applications indicated that the percent of difference between the predicted concentrations estimated by the PPK final model and the observed concentrations were -4.3%-+25%. Correlation analysis displayed that there was a linear correlation between observed and predicted values (y=1.35x+0.39, r=0.9639, P<0.0001). CONCLUSION: The PPK final model of digoxin in older Chinese patients can be established using the NONMEM software, which can be applied in clinical practice.


Subject(s)
Anti-Arrhythmia Agents/pharmacokinetics , Digoxin/pharmacokinetics , Heart Failure/drug therapy , Aged , Aged, 80 and over , Anti-Arrhythmia Agents/blood , Anti-Arrhythmia Agents/therapeutic use , Asian People , Computer Simulation , Digoxin/blood , Digoxin/therapeutic use , Female , Humans , Male , Metabolic Clearance Rate , Middle Aged , Models, Biological , Regression Analysis , Retrospective Studies , Software
10.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(15-16): 1185-9, 2010 May 01.
Article in English | MEDLINE | ID: mdl-20356808

ABSTRACT

A simple and sensitive high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method has been developed and validated for simultaneous quantification of five local anesthetics in human plasma: procaine, lidocaine, ropivacaine, tetracaine and bupivacaine. In an ice-water bath, 500 microL plasma sample, containing 100 microg/mL neostigmine methylsulfate as anticholinesterase, was spiked with carbamazepine as internal standard and alkalized by sodium hydroxide. Liquid-liquid extraction with ethyl ether was used for plasma sample preparation. The chromatographic separation was achieved on a Kromosil ODS C18 column with a mobile phase consisting of 30 mM potassium dihydrogen phosphate buffer (0.16% triethylamine, pH adjusted to 4.9 with phosphoric acid) and acetonitrile (63/37, v/v). The detection was performed simultaneously at wavelengths of 210 and 290 nm. The chromatographic analysis time was 13 min per sample. The calibration curves of all five analytes were linear between 0.05 and 5.0 microg/mL (r(2) > or = 0.998). Precision ranged from 1.4% to 7.9% and accuracy was between 91.7% and 106.5%. The validated method is applicable for simultaneous determination of procaine, lidocaine, ropivacaine, tetracaine and bupivacaine for therapeutic drug monitoring and pharmacokinetic study.


Subject(s)
Amides/blood , Bupivacaine/blood , Chromatography, High Pressure Liquid/methods , Lidocaine/blood , Procaine/blood , Tetracaine/blood , Amides/pharmacokinetics , Drug Stability , Humans , Least-Squares Analysis , Lidocaine/pharmacokinetics , Reproducibility of Results , Ropivacaine , Sensitivity and Specificity , Tetracaine/pharmacokinetics
11.
Br J Clin Pharmacol ; 68(1): 47-60, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19660003

ABSTRACT

AIMS: This study was aimed at determining the population pharmacokinetics of sirolimus and identifying factors that explain pharmacokinetic variability in de novo Chinese adult renal transplant patients. METHODS: Data were retrospectively extracted from a formal multicentre clinical trial, which was originally designed to evaluate the safety and efficacy of cyclosporin dose reduction and cyclosporin elimination in patients receiving sirolimus. All patients received 12-month treatment, i.e. induction therapy with cyclosporin, sirolimus and corticosteroids during the first 3 months followed by either cyclosporin dose reduction or cyclosporin discontinuation thereafter. Eight-hundred and four sirolimus trough blood concentrations (C(0)) from 112 patients were used to develop a population pharmacokinetic model using the NONMEM program. A one-compartment model with first-order absorption and elimination was selected as the base model. The influence of demographic characteristics, biochemical and haematological indices, cyclosporin daily dose, cyclosporin C(0) as well as other commonly used co-medications were explored. RESULTS: The typical values with interindividual variability for apparent clearance (CL/F) and apparent volume of distribution (V/F) were 10.1 l h(-1) (23.8%) and 3670 l (56.7%), respectively. The residual variability was 29.9%. CL/F decreased significantly with silymarin or glycyrrhizin co-therapy in hepatically impaired patients, and with increasing total cholesterol levels or cyclosporin C(0). Moreover, CL/F increased nonlinearly with increasing sirolimus daily dose. The median parameter estimates from a nonparametric bootstrap procedure were comparable and within 5% of the estimates from NONMEM. CONCLUSIONS: These results provide important information for clinicians to optimize sirolimus regimens in Chinese renal transplant patients.


Subject(s)
Graft Rejection/prevention & control , Immunosuppressive Agents/pharmacokinetics , Kidney Transplantation , Sirolimus/pharmacokinetics , Adolescent , Adrenal Cortex Hormones/administration & dosage , Adult , Aged , Aged, 80 and over , Asian People/ethnology , Cyclosporine/administration & dosage , Drug Therapy, Combination , Female , Humans , Immunosuppressive Agents/administration & dosage , Male , Middle Aged , Retrospective Studies , Sirolimus/administration & dosage , Young Adult
12.
Yao Xue Xue Bao ; 41(9): 893-8, 2006 Sep.
Article in Chinese | MEDLINE | ID: mdl-17111840

ABSTRACT

AIM: To develop limited sampling strategy (LSS) for estimation of C(max) and AUC(0-t) and assessing the bioequivalence of two pioglitazone hydrochloride (PGT) preparations. METHODS: Healthy subjects (n = 20), enrolled in a bioequivalence study, were received 30 mg PGT po of reference or test formulation. The plasma concentration of PGT was determined by the validated HPLC method. A multiple linear regression analysis of the Cmax and AUC(0-t) against the PGT concentration for the reference formulation was carried out to develop LSS models to estimate these parameters. The models were internally validated by the Jackknife method and externally validated using simulated sets generated by Monte Carlo method. The best model was employed to assess bioequivalence of the two PGT formulations. RESULTS: The linear relationship between pharmacokinetics parameters and single concentration point was poor. Several models for these parameters estimation met the predefined criteria (r2 > 0.9). The Jackknife validation procedure revealed that LSS models based on two sampling times (C1, C2.5 and C1.5, C2.5 for C(max); C1.5, C9 and C2.5, C9 for AUC(0-t) predict accurately. Mean prediction errors (MPE) were less than 3%, and mean absolute prediction error (MAE) were less than 9%. The prediction error (PE) beyond 20% was less than 5% of total samples. Model external validation by Monte Carlo simulated data indicated that the most informative sampling combinations were C1.5, C2.5 for C(max), and C1.5, C9 for AUC(0-t), respectively. MPE and MAE of the proposed models were less than 5% , and 9% respectively. The PE beyond 20% was less than 5% of the total. Bioequivalence assessment of the two PGT formulations, based on the best LSS models, provided results similar to those obtained using all the observed concentration-time data points, and indicated that the two PGT formulations were bioequivalent. CONCLUSION: The LSS method for bioequivalence assessment of PGT formulations was established and proved to be applicable and accurate. Thus, it could be considered appropriate for PGT bioequivalence study with inexpensive cost of sampling acquisition and analysis. Key words: pioglitazone hydrochloride; limited sampling strategy; Monte Carlo simulation; bioequivalence


Subject(s)
Hypoglycemic Agents/pharmacokinetics , Thiazolidinediones/pharmacokinetics , Administration, Oral , Adult , Area Under Curve , Chromatography, High Pressure Liquid , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/blood , Male , Models, Biological , Monte Carlo Method , Pioglitazone , Sample Size , Therapeutic Equivalency , Thiazolidinediones/administration & dosage , Thiazolidinediones/blood
13.
Pharmazie ; 61(1): 18-20, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16454200

ABSTRACT

A specific and accurate reversed-phase HPLC with UV detection was developed for the assay of atorvastatin in beagle dog plasma. Indomethacin was used as the internal standard. Atorvastatin was extracted by protein precipitation, the extracts were injected into a Kromasil C8 column (150 mm x 4.6 mm, 5 microm) with UV wavelength set at 270 nm. The mobile phase consisted of acetonitrile:0.1 mol/L ammonium acetate buffer (pH 4.0) (65:35% v/v) at a flow rate of 1.0 ml/min. The column was at ambient temperature (25 degrees C). The injection volume was 25 microl. The blank plasma did not interfere with the determination of atorvastatin and indomethacin. A good linear relationship was obtained between the peak area ratio of atorvastatin to indomethacin and the concentration of atorvastatin over the range of 0.05 to 2.5 microg/mL. The limit of quantification was 25 ng/mL, the limit of detection was 8 ng/ml. The total chromatographic analysis time was within 9 min. The method is accurate, precise and fast for the assay of atorvastatin in plasma following oral administration of an atorvastatin SMEDDS to healthy beagle dogs.


Subject(s)
Heptanoic Acids/administration & dosage , Heptanoic Acids/pharmacokinetics , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacokinetics , Pyrroles/administration & dosage , Pyrroles/pharmacokinetics , Animals , Atorvastatin , Chromatography, High Pressure Liquid , Dogs , Drug Delivery Systems , Emulsions , Indicators and Reagents , Male , Reproducibility of Results , Spectrophotometry, Ultraviolet
14.
Yao Xue Xue Bao ; 40(11): 982-7, 2005 Nov.
Article in Chinese | MEDLINE | ID: mdl-16499080

ABSTRACT

AIM: To prepare self-microemulsifying drug delivery system (SMEDDS) containing atorvastatin,and decrease its size to improve the solubility in the stomach. And to study the effect of the resultant microemulsion in reducing the presystemic clearance in the gastrointestinal mucosa and hepatic first-pass metabolism, improving the oral bioavailability, and reducing side effect and expenditure. METHODS: Pseudoternary phase diagrams were used to evaluate the self-microemulsification existence area. The HPLC analyses in vitro and in vivo were set up. Solubility in various vehicles was determined. The self-microemulsification efficiency was assessed, such as self-microemulsification time, stability, particle size and zeta potential. SMEDDS containing atorvastatin, non-ionic surfactant and lipid were prepared. Droplet size/distributions and zeta potential of the resultant microemulsion were determined. Photos were taken with transmission electron microscope. Oral bioavailability was studied on prepared SMEDDS hard capsules and compared with that of the conventional tablet in Beagle dogs in vivo. RESULTS: The optimal formulations had wide microemulsion existent field and had good self-microemulsifying efficiency. Droplet size was within 100 nm and showed Gaussian distribution. After oral administration of SMEDDS capsules and the conventional tablet to fasted Beagle dogs, the Cmax from SMEDDS was greater than that of the conventional tablet. AUC from zero to 24 h of SMEDDS was about 1.5-fold higher than that of the conventional tablet. Oral bioavailability of atorvastatin SMEDDS was greater than that of the conventional tablet. CONCLUSION: The results indicated the potential use of SMEDDS for the delivery of atorvastatin to increase its oral bioavailability.


Subject(s)
Drug Delivery Systems , Heptanoic Acids/pharmacokinetics , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacokinetics , Polyethylene Glycols/chemistry , Pyrroles/pharmacokinetics , Administration, Oral , Animals , Area Under Curve , Atorvastatin , Biological Availability , Dogs , Emulsions , Glycerol/analogs & derivatives , Glycerol/chemistry , Heptanoic Acids/administration & dosage , Heptanoic Acids/blood , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/blood , Male , Particle Size , Pyrroles/administration & dosage , Pyrroles/blood , Solubility
15.
Yao Xue Xue Bao ; 39(12): 971-4, 2004 Dec.
Article in Chinese | MEDLINE | ID: mdl-15813023

ABSTRACT

AIM: To determine the relationship between C3435T mutation in exon 26 of the human multidrug resistant 1 gene and cyclosporine (CsA) pharmacokinetic (PK) parameters among healthy Chinese volunteers by nonlinear mixed effect model (NONMEM). METHODS: Twenty healthy subjects were given orally a single dose of 500 mg CsA in microemulsion solution. Blood CsA concentrations were measured with HPLC and the genotype for the C3435T polymorphism of MDR1 gene was determined with the PCR and restriction fragment length polymorphism. The results were further confirmed by sequencing. NONMEM was performed to assess the effect of genotype on CsA PK profile. RESULTS: MDR1 C3435T genotype was identified as the best predictor of CsA systemic exposure. The relative bioavailability of CsA was 40% higher in subjects who carried at least one 3435C allele compared to that of TT type individuals in the study population. CONCLUSION: The MDR1 C3435T genotype offers a potential basis of mechanism to explain inter-subject differences in CsA oral bioavailability.


Subject(s)
Cyclosporine/pharmacokinetics , Genes, MDR/genetics , Mouth/metabolism , Polymorphism, Genetic , Administration, Oral , Adult , Biological Availability , Cyclosporine/administration & dosage , Exons , Genetics, Population , Genotype , Humans , Male
16.
Ai Zheng ; 21(8): 828-32, 2002 Aug.
Article in Chinese | MEDLINE | ID: mdl-12478886

ABSTRACT

BACKGROUND & OBJECTIVE: Boanmycin (BAM), a single A6 component of the bleomycin complex, is effective against a panel of cancers in clinical trials. Chemotactic peptide can activate and attract leukocytes and macrophages that may interfere with the process of tumor growth, invasion, and metastasis. This study was designed to investigate the antitumor activity of BAM in combination with chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine(fMLP). METHODS: Cytotoxicity of BAM and fMLP to tumor cells was determined by MTT assay, particularly in presence of macrophages. Therapeutic effect was evaluated by using the model of subcutaneously transplanted hepatoma 22 in mice. RESULTS: In vitro experiment showed that BAM and fMLP had no synergism in cytotoxicity to tumor cells. However, in the presence of macrophages, BAM at concentrations of 10, 30, and 100 micrograms/ml in combination with fMLP 20 micrograms/ml displayed synergistic effect in cytotoxicity. In all in vivo experiments, fMLP administered peritumorally 3 times at the dose of 1 mg/mouse showed no significant growth inhibition. Three settings of BAM and fMLP combination included: (1) BAM, administered peritumorally x 3, was started 24 h after tumor inoculation. BAM (0.5 mg/kg) alone and BAM-fMLP combination inhibited the growth of hepatoma 22 by 26.6% and 64.7%, respectively (P < 0.05, CDI = 0.36) on day 13. (2) BAM, administered i.p. x 3, was started 24 h after tumor inoculation. The tumor growth in BAM (1 mg/kg) group was faster than that in BAM-fMLP combination group. On day 14, BAM (1 mg/kg) alone and BAM-fMLP combination suppressed the tumor growth by 11% and 70.6%, respectively (P < 0.05, CDI = 0.42). (3) BAM, administered i.p. x 3, was started 96 h after tumor inoculation. The tumor growth in BAM (1 mg/kg) group was faster than that in BAM-fMLP combination group. On day 13, BAM (1 mg/kg) alone and BAM-fMLP combination suppressed the tumor growth by 38.2% and 77.1%, respectively (P < 0.05, CDI = 0.51). As shown in all in vivo experimental settings, antitumor effect of BAM in combination with fMLP was much more potent than that of BAM alone. CONCLUSION: This experiment shows that chemotactic peptide fMLP may enhance the antitumor effect of BAM and the enhancement may need the participation of macrophages. Chemotactic modulation may play a role in cancer chemotherapy.


Subject(s)
Antineoplastic Agents/pharmacology , Bleomycin/analogs & derivatives , Bleomycin/pharmacology , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Animals , Body Weight/drug effects , Dose-Response Relationship, Drug , Drug Synergism , Male , Mice , Neoplasm Transplantation , Neoplasms, Experimental/pathology , Neoplasms, Experimental/prevention & control , Time Factors , Tumor Cells, Cultured/drug effects
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