Tubeimoside­1 induces apoptosis in human glioma U251 cells by suppressing PI3K/Akt­mediated signaling pathways.

Tubeimoside-1 (TBMS1), a traditional Chinese herb extracted from Bolbostemma paniculatum (Maxim.), induces apoptosis in a number of human cancer cell lines. TBMS1 has been reported to induce apoptosis in human glioma cells, however the mechanism remains to be elucidated. The present study explored TBMS1­induced PI3K/Akt­related pathways in human glioma cells. The human glioma U251 and the human astrocyte (HA) cell lines were treated with various concentrations of TBMS1. MTT assays were conducted to analyze cell viability. Cell cycle distribution and the rate of apoptosis were assessed using flow cytometry. BrdU incorporation and Hoechst 33342 staining were performed to analyze the cell cycle and apoptosis, respectively. Western blotting was performed to investigate protein expression levels. The results demonstrated that TBMS1 reduced cell viability in human glioma cells U251 by suppressing Akt phosphorylation. Subsequently, TBMS1 inhibited DNA synthesis and induced G2/M phase arrest by targeting the PI3K/Akt/p21 and the cyclin­dependent kinase 1/cyclin B1 signaling cascades. In addition, TBMS1 triggered apoptosis via the PI3K/Akt­mediated Bcl­2 signaling pathway. These results demonstrated that TBMS1 prevented the progression of gliomas via the PI3K/Akt­dependent pathway, which provided a theoretical basis for in vivo studies to use TBMS1 as potential therapy for the prevention of cancer.

[Absorption, distribution, metabolism, excretion and toxicity of biologics and its application in pharmacokinetic modeling].

Recently, more and more attentions of drug development are placed to macromolecules, such as monoclonal antibodies, proteins, etc. It has become one of the most promising areas in drug research and development in 21st Century. In terms of the structure and the ADMET (absorption, distribution, metabolism, excretion and toxicity), macromolecules is different from small molecule drugs, which lead to a distinct modeling strategy. The characterization of biologics ADMET processes and its application in the PK model selection of macromolecules are reviewed in this paper.

Transcriptional Regulation of CYP3A4/2B6/2C9 Mediated via Nuclear Receptor PXR by Helicid and Its Metabolites.

Objective. This study aims at establishing and validating an in vitro system to screen drug inducers of CYPs mediated via hPXR, as well as studying transcriptional regulation of CYPs mediated via hPXR by helicid and its two metabolites. Methods. Cloning the nuclear receptor hPXR and the promoters of CYP3A4, CYP2B6, CYP2C9, and inserting the trans-element to the upstream of firefly luciferase reporter gene of the pGL4.17 vectors, then cotransfecting the report vectors and hPXR expression plasmid to HepG2 cell line. After 24 hours, the transfected cells were treated with helicid (0.004, 0.04, and 0.4 µmol/L) and its metabolite I and metabolite II (0.0004, 0.004, and 0.04 µmol/L) for 48 h, while rifampin (10 µmol/L) was included as the positive control and 0.1% DMSO as the negative control group. Cells were lysized and luciferase activity was determined using a dual luciferase reporter assay kit. Results. Helicid and its metabolites did not significantly increase promoter activities of CYP3A4, CYP2B6, and CYP2C9 in HepG2 cells transfected with PXR expression plasmid (P > 0.05). Conclusion. PXR-expressed CYP3A4, CYP2B6, and CYP2C9 dual luciferase reporter gene platforms were successfully established, and helicid and its metabolites I, II do not significantly induce the transcription of CYP3A4, CYP2B6, and CYP2C9.

Influence of ORM1 polymorphisms on the maintenance stable warfarin dosage.

PURPOSE: ORM1 is a plasma drug binding protein. Its polymorphism rs17650 (S>F) has been reported to be an important factor affecting the binding ability and effect of antiretroviral protease inhibitors. The aim of this study was to determine whether the ORM1 rs17650 polymorphism also influences warfarin therapy. METHODS: A total of 191 Chinese patients with steady-dose warfarin therapy were enrolled in this study. The patients were studied for warfarin maintenance dose, the ORM1 rs17650 polymorphism, and two polymorphisms previously demonstrated to affect warfarin response [CYP2C9 rs1057910 (3) and VKORC1 rs7294 (-1639 G>A)]. RESULTS: Warfarin dose was partially correlated with the VKORC1 rs7294, CYP2C9 rs1057910 and ORM1 rs17650 polymorphisms. Patients carrying the wild-type of these three genes (n = 96) took a mean dose of 3.0 ± 1.1 mg warfarin, which was significantly higher than that taken by the 52 S patients (2.7 ± 0.7) and 11 S S patients (2.5 ± 0.6 mg) (p = 0.048). CONCLUSION: We identified ORM1 as another polymorphic gene affecting warfarin dose requirements. ORM1 S carriers require lower maintenance doses to achieve and maintain an optimal level of anticoagulation.

An indirect sandwich ELISA for the determination of agkisacutacin in human serum: application to pharmacokinetic study in Chinese healthy volunteers.

The platelet receptor glycoprotein Ib-IX-V complex (GPIb-IX-V) plays a dominant role in the first step of platelet adhesion and arterial thrombus formation. Agkisacutacin, a C-type lectin-like protein (CLP) from Agkistrodon acutus venom, had been previously identified as an antagonist of platelet aggregation and a membrane glycoprotein Ib-binding protein (GPIb-bp). For the analysis of pharmacokinetics of agkisacutacin, an indirect sandwich enzyme-linked immunosorbent assay (ELISA) was established and validated to quantify agkisacutacin in human serum. The method was precise and accurate over the entire linear range of 1.0 and 1000 pg/mL with a lower limit of quantification of 1.0 pg/mL. The intra- and inter-assay coefficient of variation ranged from 0.7 to 4.2% and 1.1 to 4.1%, respectively. Recovery obtained from the accuracy test, using three concentration levels, varied between 96.1 and 110.6%, confirming the assay's reliability. The long-term study showed agkisacutacin was stable at -70 °C up to 46 days. This ELISA was first used to assess the pharmacokinetics of agkisacutacin in healthy volunteers. The characteristics of pharmacokinetic showed that agkisacutacin could rapidly combine with GPIb and slowly dissociate from GPIb-bound form in the body.

Development and validation of a simple and sensitive liquid chromatography-tandem mass spectrometry method for quantifying trimetazidine in human plasma.

1. A simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for quantifying trimetazidine in human plasma was developed and validated. Sample preparation was based on deproteinating with acetonitrile. 2. Chromatography was performed on a C18 analytical column (5 mum; 150 x 2.1 mm i.d.) and the retention times for trimetazidine and cetirizine (used as the internal standard) were 1.8 and 3.0 min, respectively. The ionization was optimized using an electrospray ionization source and enhanced selectivity was achieved using tandem mass spectrometry. The calibration curve ranged from 0.1 to 200 ng/mL. The inter-day precision, accuracy and the relative standard deviation (RSD) were all < 15%. The analyte was shown to be stable over the time-scale of the entire procedure. 3. The robustness of the method was demonstrated by the good reproducibility of the results obtained during the analysis of clinical samples.

Sensitive determination of 20(S)-protopanaxadiol in rat plasma using HPLC-APCI-MS: application of pharmacokinetic study in rats.

20(S)-Protopanaxadiol (PPD), the main metabolite of protopanoxadiol type ginsenosides (e.g. Rg3 and Rh2), is a very promising anti-cancer drug candidate. To evaluate the pharmacokinetic property of PPD, we reported a reliable, sensitive and simple method utilizing liquid chromatography (HPLC)-atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) to determine PPD. PPD and the internal standard, panoxadiol (PD) were extracted from plasma with acetic ether, separated on a C18 reverse column, and then analyzed by APCI-MS. Targeting fragment ion at m/z 425 for both PPD and PD was monitored in selected-ion monitoring (SIM) mode. PPD can be quantitatively determined at the concentration as low as 1 ng/mL using 200 microL plasma. And the sensitive method showed excellent linearity over a range from 1 to 1000 ng/mL, high recovery, accuracy and precision at the concentrations of 2.5, 100.0 and 1000.0 ng/mL, respectively. The method was successfully applied to pharmacokinetic study of PPD in rats. Pharmacokinetic parameters were calculated and absolute bioavailability of PPD was 36.8+/-12.4%, at least ten times higher than that of Rg3 and Rh2, indicating its good absorption in gastrointestinal tract. It was further suggested that PPD be a promising anti-cancer candidate and probably responsible for the observed pharmacological activity of Rg3 and Rh2.

Gender difference regarding schizandrin pharmacokinetics in rats.

The difference in the pharmacokinetics of schizandrin (SZ) in male and female rats was studied. SZ concentrations in the plasma were determined after the intragastric (i.g) administration of 10 mg/kg and the intravenous (i.v) administration of 5 mg/kg in male and female rats, respectively. It was found that the plasma concentrations of SZ in female rats were significantly higher than those in male rats. Drug absolute bioavailability, based on the area under curve (AUC(0-tn)), in female rats was roughly 20 times of that in male rats. The terminate half-life (T(1/2)) in male rats was shorter than that in female rats. These results demonstrate the existence of marked gender differences for SZ in rats.

Pharmacokinetics of rosuvastatin when coadministered with rifampicin in healthy males: a randomized, single-blind, placebo-controlled, crossover study.

BACKGROUND: Rifampicin (rifampin) has been reported to have drug-drug interaction with several 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors due to its ability to influence the function of cytochrome P450 enzymes or transporters. Rosuvastatin is absorbed from the blood into the liver by organic anion transporting polypeptide 1B1 and is then metabolized by cytochrome P450 isozyme 2C9. OBJECTIVE: The aim of this study was to examine the effect of rifampicin on the pharmacokinetics of rosuvastatin. METHODS: This was a randomized, single-blind, placebo-controlled, crossover study, with a 4-week washout period. Healthy male volunteers were treated for 6 days with rifampicin 450 mg or placebo once daily. On days 0 and 7, a single oral dose of rosuvastatin 20 mg was administered. Plasma concentrations of rosuvastatin were measured by liquid chromatography-tandem mass spectrometry. RESULTS: A total of 18 healthy Chinese male volunteers (mean [SD] age, 21 [2] years; weight, 62 [7] kg; and body mass index was within the normal range [22.0-24.0 kg/m2]) were included in the study. The plasma concentrations of rosuvastatin were not significantly changed by pretreatment with rifampicin, although there was considerable interindividual variation in the plasma concentration of rosuvastatin. During the rifampicin phase, the AUC(0-infinity) of rosuvastatin decreased in 10 and increased in 8 of the 18 subjects. In 3 of the 8 subjects, the AUC(0-infinity) of rosuvastatin during the rifampicin phase was > or = 50% compared with the placebo phase; and only 1 increased by more than double (183%). Of those in the decreased group (n = 10), the AUC(0-infinity) values were decreased by >50% in 3 subjects and were not decreased by >30% in the remaining 7 subjects. The mean AUC(0-infinity) of rosuvastatin was 95.8% (110.4 [41.4] vs 115.3 [30.9] ng/mL . h(-1)) of the corresponding value during the placebo phase (P = NS). There was no statistically significant difference in either C(max) or t(1/2) of rosuvastatin between the rifampicin-treated and placebo groups (18.5 [6.3] vs 16.5 [5.5] ng/mL; 12.8 [3.0] vs 13.3 [2.8] h). The oral clearance of rosuvastatin was not significantly affected by rifampicin pretreatment either (0.4 [0.3] vs 0.3 [0.2] L . h; P = 0.072). CONCLUSION: The pharmacokinetics of rosuvastatin were not significantly changed by coadministration of rifampicin in this small group of healthy male volunteers.

Globalization of quantitative pharmacology: first international symposium of quantitative pharmacology in drug development and regulation.

The First International Symposium on Quantitative Pharmacology in Drug Development and Regulatory Sciences was held this past October in Nanjing, China, marking the first time scientists from around the globe gathered to discuss topics related to quantitative pharmacology in the Far East. With the recent trend toward global drug development and clinical trials in nontraditional countries, China has been regarded by many as the next frontier for the pharmaceutical industry. Quantitative pharmacology embraces all phases of pharmaceutical research and development, providing a mechanism to bridge decision making from one phase of development to the next, and it facilitates multidisciplinary partnerships through the assembly of both data and models that describe complex biological, biopharmaceutic, and clinical settings. Efforts in China are at an early stage, but it is clear that Chinese scientists embrace the discipline and are keen to promote this methodology in the registration of new drugs in China. While challenges exist, they represent an exciting area of future collaboration.

[Enzyme kinetics of schizandrin metabolism and sex differences in rat liver microsomes].

To study the enzyme kinetics of schizandrin metabolism in different gender in rat liver microsomes, liver microsomes were prepared from male or female rats. Schizandrin was incubated with rat liver microsomes. Schizandrin and its metabolites were isolated and identified by HPLC-UV method. Vmax, Km and Cl(int) of schizandrin in male and female rat liver microsomes were (21.88 +/- 2.30) and (0.61 +/- 0.07) micromol x L(-1) x min(-1) x mg(-1) (protein), (389.00 +/- 46.26) and (72.64 +/- 13.61) micromol x L(-1), (0.0563 +/- 0.0007) and (0.0084 +/- 0.0008) min x mg(-1) (protein), respectively. The major metabolites of schizandrin in female and male rat liver microsomes were 7,8-dihydroxy-schizandrin (M1) and 7, 8-dihydroxy-2-demethyl schizandrin (M2b), respectively. Ketoconazole, quinidine, and orphenadrine had different level effects on schizandrin metabolism in both male and female rat liver microsomes, and cimetidine still had some inhibitory effect in male liver microsomes. CYP3A and CYP2C11 may be the main P450 enzymes in schizandrin metabolism and their difference in rat liver microsomes may be the main reason for the sex difference of metabolic enzyme kinetics and metabolites of schizandrin in rats.

[Pharmacokinetics of triptolide in Beagle dogs].

The aim of this paper is to develop and validate a rapid and sensitive LC-APCI/MS method for the determination of triptolide (TP) in plasma and to study the pharmacokinetic properties of TP in Beagle dogs. Sample preparation consisted of liquid-liquid extraction of interests. with ethyl acetate from dog plasma. The analytes and internal standard prednisolone were well separated on a Zorbax Extend-C18 analytical column. Plasma TP was detected by selected-ion monitoring (SIM) of LC-APCI/MS as its deprotonated molecular ions [M - H] - at m/z 358.9. Pharmacokinetic studies were undertaken in dogs following an iv dose of 0.05 mg x kg(-1) of TP or an ig dose of 0.05, 0.08, 0.1 mg x kg(-1), separately. The pharmacokinetic parameters were calculated by DAS software. Calibration curves were linear over the concentration range of 1 - 200 ng x mL(-1) of TP with the within- and between-batch precisions less than 10%. The within and between-batch accuracy was 95.0% to 105.0%. Recovery of LC-MS method for TP in plasma was over 75%. The T1/2beta was (2.5 +/- 0.8) h after intravenous administration of TP at the dose of 0.05 mg x kg(-1). There were no significant differences in T(max), T1/2 alpha and T1/2 beta among the three ig dosage groups. AUC and C(max) increased proportionally with doses. The absolute bioavailability of TP after ig administration of 0.05 mg x kg(-1) was (75 +/- 17)%. The LC-MS method for determination of triptolide in dog plasma was sensitive and rapid. It was showed that the elimination of triptolide was rapid. The absolute bioavailability of triptolide given orally was high.

Determination of ginsenoside Rd in dog plasma by liquid chromatography-mass spectrometry after solid-phase extraction and its application in dog pharmacokinetics studies.

A sensitive liquid chromatography-mass spectrometric (LC/MS) method for the quantification of ginsenoside Rd in dog plasma was developed and validated after solid-phase extraction (SPE). Chromatographic separation was achieved on a reversed-phase Cromosil C(18) column with the mobile phase of acetonitrile-ammonium chloride (500 micromol/L) and step gradient elution resulted in a total run time of about 5.5 min. The analytes were detected by using an electrospray negative ionization mass spectrometry in the selected ion monitoring (SIM) mode. A good linear relationship was obtained in the concentration range studied (0.005-2.500 microg/mL) (r=0.9998). Lower limit of quantification (LLOQ) was 5 ng/mL by using 500 microL plasma sample. Average recoveries ranged from 70.71 to 75.89% in plasma at the concentrations of 0.010, 0.100 and 2.500 microg/mL. Intra- and inter-day relative standard deviations were 8.49-11.71 and 5.71-16.48%, respectively. This method was successfully applied to the pharmacokinetic studies on dogs. The absolute bioavailability of Rd in dogs was 0.26%.

Quantitative determination of ginsenoside Rh2 in rat biosamples by liquid chromatography electrospray ionization mass spectrometry.

Ginsenoside Rh2 is a "hot" natural compound with great potential as a new anti-cancer drug based on abundant pharmacological experiments. However, no systemic pharmacokinetic study of Rh2 was reported because current analysis methods could not fully meet the requirements. Thus, we developed a simple LC/MS method with highly improved sensitivities for the determination of Rh2 in rat plasma, bile, urine, feces and most tissues. The tissues and feces were firstly homogenized mechanically using buffer and methanol as the media, respectively. Plasma, bile, urine and tissue homogenates were extracted with diethyl ether for sample preparation. Feces homogenates were directly deproteinized with acetonitrile. The subsequent analysis procedures were performed on a Shimadzu LCMS2010A system (electrospray ionization single quadrupole mass analyzer), with an ODS column (150 mm x 2.0-mm i.d., 5 microm) plus a C18 guard column for separation and ammonium chloride (500 micromol) as mobile phase additive. The proportions of mobile phase were changed timely according to gradient programs. Chlorinated adducts of molecular ions [M + Cl]- of Rh2 at m/z 657.35 and internal standard digitoxin at m/z 799.55 were monitored in selective ion monitoring mode of negative ions. The method was validated to be accurate, precise and rugged with good linearity in all matrices, according to the FDA guidelines. The lower limits of quantitation in rat plasma, urine and feces were 0.2, 0.2 and 20 ng/mL respectively. Stability studies were also performed, indicating that there were no stability-related problems in the analytical procedure of Rh2. The proposed method was successfully applied to the preclinical pharmacokinetic research of Rh2 in rats, including plasma kinetics, tissue distribution and excretion studies.

Pharmacokinetic and pharmacodynamic population modeling of orally administered rabeprazole in healthy Chinese volunteers by the NONMEM method.

The pharmacokinetic-pharmacodynamic (PK-PD) relationship of the proton pump inhibitor rabeprazole in healthy Chinese volunteers was characterized via a population approach. Healthy Chinese male volunteers were enrolled in the clinical trial. Subjects were divided into three groups by their CYP2C19 genotype. Serum concentrations of rabeprazole were determined using high performance liquid chromatography (HPLC). The intragastric pH values were monitored simultaneously. Data analysis was performed using nonlinear mixed-effects modeling as implemented in the NONMEM software package. The final PK-PD model incorporated a one-compartment PK model with one-order absorption from the gastroenteric trace, first-order elimination pathway with one fixed-effect genotype modeling, and a full sigmoidal Emax PD model (X +/- SE: E0 = 2.30 +/- 0.189; Emax = 7.32 +/- 0.662; EC50 = 51.3 +/- 2.142 ng/ml; Hill coefficient = 5.00 +/- 0.556). The time profiles for concentration and pH value, as well as the concentration-pH value relationship of rabeprazole in healthy Chinese volunteers were well described by the developed population PK-PD model.

PK-PD modeling of irbesartan in healthy Chinese adult volunteers under non-steady-state conditions.

The purpose of this study was to construct a pharmacokinetic/pharmacodynamic model (PK-PD model) of irbesartan in healthy Chinese adult volunteers under non-steady-state conditions and provide relevant PK/PD parameters for use in clinical practice. Thirty-six healthy Chinese adult male volunteers received 150 or 300 mg irbesartan orally in tablet form (2 groups; n = 18 per group). Plasma concentrations were determined by HPLC and pharmacological effects, including effects on systolic (SBP) and diastolic blood pressure (DBP) were measured simultaneously. The experimental data were quantitatively analyzed according to the PK-PD model construct. PK/PD parameters were calculated. Blood pressure remained almost unchanged at an irbesartan dose of 150 mg under non-steady-state conditions. After a single dose of 300 mg, the pharmacokinetic profiles of irbesartan conformed to a two-compartment model. There were hysteresis loops between drug effects and plasma concentrations. The relationship between effects and effect compartment concentrations (Ce) could be represented by the sigmoid-Emax model. The Emax values for the inhibitory effects on SBP and DBP of irbesartan were 14.8 +/- 1.5 and 9.8 +/- 2.1 mmHg respectively, the EC50 values were 0.29 +/- 0.11 and 0.18 +/- 0.07 microg x ml(-1), while the K(eo) values were 0.62 +/- 0.09 and 0.68 +/- 0.07 h(-1), respectively. The PK-PD model of irbesartan was developed in healthy Chinese adult male volunteers, and may provide a more rational basis for dosage individualization.

Pharmacokinetic and pharmacodynamic interaction between irbesartan and hydrochlorothiazide in renal hypertensive dogs.

Combined irbesartan/hydrochlorothiazide (HCTZ) formulations are often used clinically. Pharmacokinetic-pharmacodynamic (PK/PD) modeling was applied to investigate the pharmacokinetic and pharmacodynamic interaction between irbesartan and HCTZ in renal hypertensive dogs at non-steady-state and steady-state. The renal hypertensive dogs were treated with oral irbesartan alone, or HCTZ alone, or the combination of irbesartan and HCTZ for 8 days. Blood pressure and plasma concentrations were measured and pharmacokinetic-pharmacodynamic parameters were analyzed. Irbesartan showed a two-compartment model pharmacokinetic profile. The concentration-time course of irbesartan was not changed by HCTZ, but irbesartan increased the peak plasma concentration and area under the curve of HCTZ at steady-state. HCTZ had no blood pressure lowering effect at non-steady-state. Irbesartan plus HCTZ had greater blood pressure lowering action than irbesartan alone. HCTZ increased actions of irbesartan. Hysteresis loops were found between effect and plasma concentrations of irbesartan after a single dose. However, hysteresis loops disappeared at steady state with more rapid realization of maximum concentration and effects. The relationship between effects and effect-compartment concentrations of the drugs was represented by a sigmoid Emax model. The results suggest synergistic pharmacodynamic interaction between irbesartan and HCTZ in renal hypertensive dogs and some differences of pharmacokinetic-pharmacodynamic properties between irbesartan and irbesartan/HCTZ combinations at non-steady-state and steady state.

Development of a HPLC-MS assay for ginsenoside Rh2, a new anti-tumor substance from natural product and its pharacokinetic study in dogs.

To develop a HPLC-MS method of determining ginsenoside Rh2 in dog plasma based on solid-phase extraction for pharmacokinetic studies. Six dogs were randomly assigned to two groups, either given 0.1 mg/kg dose intravenously or 1 mg/kg dose through oral gavage. Analysis using high performance liquid chromatography (HPLC) with ODS column, followed by detection with electrospray ionization(ESI) mass spectrometry(MS) in negative ion mode with 500 microM ammonium chloride in the mobile phase. The assays were validated over the concentration range of 2.0-1250.0 ng/ml in dog plasma. The intra- and inter- day precision were less than 10% in terms of RSD. The overall recovery was more than 80%. The validated assay was suitable for pharmacokinetic studies of ginsenoside Rh2 and the observed oral bioavailabilities of Rh2 were 17.6% and 24.8% for male and female dogs respectively.

Pharmacokinetic and pharmacodynamic of irbesartan in renal hypertensive dogs under non-steady-state and steady-state conditions.

The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of irbesartan in renal hypertensive dogs under non-steady-state and steady-state conditions using pharmacokinetic-pharmacodynamic (PK/PD) modeling. Drugs were administered intragastrically to renal hypertensive dogs, plasma drug concentration was determined by HPLC method and Pharmacologic effects, including SBP, DBP, dp/dtmax and LVSP, were measured simultaneously. AT II, Aldosterone (ALD) and Endothelin (ET) were also used as measurement of effect. The PK and PD data were quantitatively analyzed according to the PK/PD model theory. The pharmacokinetic profiles of irbesartan conformed to a two-compartment open model. There was hysteresis loops between effects and plasma concentrations under non-steady-state condition. The relationship between effects and effect compartment concentrations (Ce) could be represented by the Sigmoid-Emax model. The Hysteresis loops disappeared under steady-state condition with more rapidly attainment of maximum concentration and effect. There were certain difference of pharmacokinetic and pharmacodynamic properties between non-steady-state and steady-state condition.

Adeno-associated virus mediated interferon-gamma inhibits the progression of hepatic fibrosis in vitro and in vivo.

AIM: To investigate the effects of adeno-associated virus (AAV) mediated expression of human interferon-gamma for gene therapy in experimental hepatic fibrosis in vitro and in vivo. METHODS: We constructed the recombinant AAV encoding human INF-gamma (rAAV- INF-gamma) and took the primary rat hepatic stellate cells and carbon tetrachloride induced rats as the experimental hepatic fibrosis model in vitro and in vivo. Immunocytochemistry analysis was used to reveal the expression of alpha-SMA, the marker protein expressed in hepatic stellate cells. The mRNA expression of TGF-beta, TIMP-1, and MMP-13 were analyzed by RT-PCR method. In vivo study, the hydroxyproline content in liver and serum AST, ALT were also detected. RESULTS: In vitro study, AAV vector could mediated efficient expression of human INF-gamma, which inhibit the activation of hepatic stellate cells, decrease the expression of alpha-SMA and mRNA of TIMP-1, TGF-beta, with the MMP-13 unchanged. In vivo study, the histological examination revealed that rAAV- INF-gamma could inhibit the progression of the hepatic fibrosis. In the rAAV-INF-gamma induced group, the hydroxyproline content and serum AST, ALT level were decreased to 177+/-28 microg/g wet liver, 668.5+/-140.0, 458.4+/-123.5 U/L, compare with the fibrosis control group 236+/-31 microg/g wet liver, 1 019.1+/-276.3, 770.5+/-154.3 U/L, respectively (P<0.01). mRNA expression of TIMP-1 in the rAAV-INF-gamma induced rat liver was decreased while no significant change was observed in TGF-beta and MMP-13. CONCLUSION: All these results indicated that rAAV-INF-gamma has potential effects for gene therapy of hepatic fibrosis, which could inhibit the progression of hepatic fibrosis.