The clinical pharmacokinetics of ribavirin after a single oral dose of 600 mg ribavirin tablets in healthy Chinese volunteers was studied. A rapid and simple high performance liquid chromatography （HPLC） method was ...The clinical pharmacokinetics of ribavirin after a single oral dose of 600 mg ribavirin tablets in healthy Chinese volunteers was studied. A rapid and simple high performance liquid chromatography （HPLC） method was developed to determine the ribavirin concentration in human plasma. C18 column was used for separation with a column temperature of 25℃, the mobile phase was ultrapure water adjusted to pH 3 with acetic acid at the flow rate of 1 mL/min, and the detection wavelength was set at 207 rim. The linear range of the standard curves was 50.4-2016.0 ng/mL and the lower limit of quantification （LLOQ） was 50.4 ng/mL. The relative recoveries of ribavirin were more than 90% in plasma. The RSD of the intra-day precision was less than 10% and that of inter-day was less than 15%. The pharmacokinetic parameters of ribavirin were calculated by WinNonlin. Results indicated that the two-compartment model was a better model for describing the pharmacokinetics profile of ribavirin than one-compartment model. The AUC0-t was 10807.8 h.ng/mL, the CL/F was 64879.5 mL, and the Cmax was 525.1 ng/mL. These results provided the experimental data for the development of ribavirin dosage form.展开更多
The sinomenine hydrochloride （SH） patch, a topical drug delivery system, was prepared and characterized. The in vitro release was studied according to the paddle-over-disk method in the appendix of Chinese Pharmacop...The sinomenine hydrochloride （SH） patch, a topical drug delivery system, was prepared and characterized. The in vitro release was studied according to the paddle-over-disk method in the appendix of Chinese Pharmacopeia （appendix XD, 2005）. Stability of SH patch was evaluated at accelerated testing conditions （40 ℃, 75% RH）. Pharmacological and pharmacokinetics study were also performed. It was found that the release of SH from patches depended on pH value of the release medium. There were no significant differences between SH patches stored for 6 mon and those stored for 0 mon in the drug content, initial adhesion, lasting stickiness, peeling strength and in vitro release. SH patches exhibited better anti-inflammatory activity as well as analgesic efficacy. More importantly, primary pharmacokinetic parameters of SH patch, such as Cmax and AUC, were much lower than those of SH solution dosed orally. In conclusion, the patch might be a promising delivery system for SH, which bypassed the gastrointestinal tract and was a convenient, efficacious, safe and non-invasive delivery method.展开更多
Clinical drug-drug interactions（DDIs） induced by CYP3A may reduce the exposure and pharmacological activity of CYP3A substrate.Up-regulation of CYP3A mRNA is often used to evaluate inductive effect of test compounds...Clinical drug-drug interactions（DDIs） induced by CYP3A may reduce the exposure and pharmacological activity of CYP3A substrate.Up-regulation of CYP3A mRNA is often used to evaluate inductive effect of test compounds on CYP3A. A quantitative real time PCR assay was developed and validated for the absolute quantification of CYP3A1 and CYP3A2 mRNA.Specific primers of CYP3A1,CYP3A2 and GAPDH（glyceraldehyde-3-phosphate dehydrogenase,as a house-keeping gene） were well designed.The relationship between threshold cycle（Ct） and logarithm of the concentrations of CYP3A1, CYP3A2 and GAPDH was linear ranged from 1 attomol/μL to 1×10~6 attomol/uL with great inter- and intra-assay reproducibility. This method was successfully applied to investigate the time courses of CYP3A1 and CYP3A2 mRNA induction in rat liver after 100 mg/kg dexamethasone（DEX） administration by intraperitoneal（i.p.） injection.The baseline levels of CYP3A1 and CYP3A2 mRNAs were 37.78 attomol/ug（total RNA） and 252.31 attomol/ug（total RNA）,respectively.CYP3A1 and CYP3A2 mRNA values increased gradually to their peak levels（19- and 8- fold vs.baseline） within 24 h and 42 h,respectively,and then returned to their baseline 60 h after DEX administration.展开更多
Novel mixed polymeric micelles formed by biocompatible polymers,mPEG-PLA and Pluronic P105,were fabricated and used as a nanocarrier to solubilize the poorly soluble anesthetic drug propofol.Propofol was added directl...Novel mixed polymeric micelles formed by biocompatible polymers,mPEG-PLA and Pluronic P105,were fabricated and used as a nanocarrier to solubilize the poorly soluble anesthetic drug propofol.Propofol was added directly to an aqueous solution of mPEG-PLA/Pluronic P105 mixed micelles and stirred into a micellar solution.The average particle size and size distribution of micelles were evaluated by the dynamic light scattering technology.Drug loading content,encapsulation efficiency and free drug concentration were determined by using ultracentrifugation and lyophilization.In vitro release characteristic of propofol formulation was investigated by dialysis method.The physical stability of mixed micelles was also assessed under storage condition（4 oC） after six months.Sleep-recovery studies in male Sprague-Dawley rats,at a dose of 10 mg/kg were performed to compare the pharmacodynamic profiles of propofol in mixed micelles with that of commercial lipid emulsion（CLE）.The results indicated that solubilization of propofol in the mixed micelles was more efficient than that in mPEG-PLA alone.Micelles with the optimized composition of mPEG-PLA/Pluronic P105/Propofol（10：4：5,w/w/w） had particle size of about 90 nm with narrow distribution（polydispersity index of about 0.2）.The content of free propofol in the aqueous phase of mixed micelles was significantly lower than that in CLE（P〈0.05）.There was no remarkable differences for particle size,polydispersity index,and free drug concentration when the mix micelles were stored at 4 oC for six months,suggesting that the propofol-loaded mixed micelles were stable for at least six months.The accumulative release of mixed micelles was significantly higher than that of CLE at the corresponding time points,suggesting that quick release rate for mixed micelles might produce favorable pharmacological effect.No significant differences in the unconsciousness time and recovery time of righting reflex were observed between the mixed micelles and CLE（P〉0.05）.In conclusion,the mixed micelle of mPEG-PLA and pluronic copolymer may be a promising candidate for intravenous delivery of propofol in clinic.展开更多
In the present work, we aimed to develop alginate-coated chitosan nanoparticles for oral insulin delivery. The N-[（2-hydroxy- 3-trimethylammonium）propyl] chitosan chloride （HTCC） was synthesized, and the quatemize...In the present work, we aimed to develop alginate-coated chitosan nanoparticles for oral insulin delivery. The N-[（2-hydroxy- 3-trimethylammonium）propyl] chitosan chloride （HTCC） was synthesized, and the quatemized chitosan nanoparticles （HTCC-T NPs） were prepared by ionic gelation of HTCC using tripolyphosphate （TPP）. The alginate-coated quatemized chitosan nanoparticles （HTCC-A NPs） were prepared by coating HTCC-T NPs with alginate （ALG） solution under mild agitation. Particle size, zeta potential, surface morphology, drug loading and entrapment efficiency of HTCC-A NPs were characterized using Zeta-sizer, TEM and HPLC assays. It was found that HTCC-A NPs exhibited uniform spherical particles with the size of （322.2±8.5） nm and positive charges （14.1±0.6） mV. Our data showed that the release behavior of HTCC-A NPs was quite different from that of HTCC-T NPs （without ALG coating） when incubated with various medium at different pH values in vitro, suggesting that ALG coating over the HTCC-T NPs improved the release profile of insulin from the NPs for a successful oral delivery. The ALG coating could also improve the stability of insulin against enzymatic degradation. From circular dichroism spectrum, it was revealed that HTCC-A NPs were capable of maintaining the conformation of insulin. The relative pharmacological bioavailability of HTCC-A NPs was 8.0%±2.5% by intraduodenal administration. The HTCC-A NPs significantly increased （P〈0.05） the relative pharmacological availability （2.2 folds） compared with HTCC-T NPs after oral administration. HTCC-A NPs significantly enhanced the in vivo oral absorption of insulin and exhibited promising potentials for oral delivery.展开更多
Mitochondria are increasingly recognized as important targets for tumor treatment because of their central roles in apoptotic pathways and cellular metabolism. Dichloroacetate （DCA）, a low molecular weight mitochond...Mitochondria are increasingly recognized as important targets for tumor treatment because of their central roles in apoptotic pathways and cellular metabolism. Dichloroacetate （DCA）, a low molecular weight mitochondria-targeting agent, exhibits potential therapeutic effects for tumors. Based on the effects of DCA on tumor cellular metabolism, we carried out this study to investigate the anti-tumor activity of DCA in C6 glioma cells in vitro. The results showed that DCA was able to increase the activity of pyruvate dehydrogenase （PDH）, induce the production of reactive oxygen species （ROS） and reduce the mitochondrial membrane potential （MMP） in C6 ceils in vitro （P〈0.05 or 0.01）, indicating that the anti-tumor effects of DCA in C6 cells could be through the activation of the mitochondrial pathway. In conclusion, mitochondria could be a viable therapeutic target for the treatment of glioma.展开更多
Considering the results of our previous research that conjugated linoleic acid mixture-paclitaxel （CLA-mixture-PTX） possesses anti-tumor activity against melanoma and brain glioma, the purpose of this study was to i...Considering the results of our previous research that conjugated linoleic acid mixture-paclitaxel （CLA-mixture-PTX） possesses anti-tumor activity against melanoma and brain glioma, the purpose of this study was to investigate the potential anti-tumor efficacy of cis-9, trans- 1 1-conjugated linoleic acid-paclitaxel （c9, tl 1-CLA-PTX） and trans- 1 O, cis- 12-conjugated linoleic acid-paclitaxel （tl0, c12-CLA-PTX） on MCF-7 breast cancer cell line in vitro and in vivo. The in vitro cytotoxicity, apoptosis induction effect and cell cycle arresting effect of c9, t1 1-CLA-PTX and t10, c12-CLA-PTX were investigated. The in vitro cellular uptake of c9, tl 1-CLA-PTX and tl0, cl2-CLA-PTX in MCF-7 cells were also analyzed. Besides, the anti-tumor activity of c9, tl 1-CLA-PTX and tl0, cl2-CLA-PTX was evaluated in MCF-7 tumor bearing nude mice in vivo. The in vitro cytotoxicity results showed that the value of ICs0 of the tl 0, c l2-CLA-PTX is （0.17±0.02） μM, compared with that of （1.08±0.15） μM in CLA-mixture-PTX and （6.50±1.20） μM in c9, tl 1-CLA-PTX treatment group （P〈0.01）. Both tl0, cl2-CLA-PTX and c9, t l 1-CLA-PTX increased the percentage of total apoptotic cells compared with that of control （P〈0.01）. And the rank of apoptosis induction efficacy was t 10, c 12-CLA-PTX〉CLA-mixture-PTX〉c9, t 11-CLA-PTX （P〈0.01）. Compared with untreated cells, the tl0, c12-CLA-PTX and c9, tl 1-CLA-PTX arrested cell cycle progression at the S and G2-M phase. The amount of cellular uptake of t 10, c 12-CLA-PTX was significantly higher than that of CLA-mixture-PTX （P〈0.01）, which was significantly higher than that of c9, t1 1-CLA-PTX （P〈0.01）. The rank of in vivo anti-tumor activity was tl0, c12-CLA-PTX〉CLA-mixture-PTX〉 c9, t1 1-CLA-PTX （P〈0.01）. In conclusion, our study demonstrated that both tl0, cl2-CLA-PTX and c9, tl 1-CLA-PTX has significant anti-tumor activity in MCF-7 cell line. And while c9, tl 1-CLA-PTX showed weaker inhibitory effect than CLA-mixture-PTX, stronger inhibitory effect was presented by t10, c12-CLA-PTX, which could be a promising alternative for CLA-mixture-PTX.展开更多
The purpose of this study was to investigate the potential antitumor efficacy of conjugated linoleic acid-paclitaxel （CLA-PTX） on B16-F10 melanoma cell line in vitro and in vivo. The in vitro cytotoxicity, apoptosis...The purpose of this study was to investigate the potential antitumor efficacy of conjugated linoleic acid-paclitaxel （CLA-PTX） on B16-F10 melanoma cell line in vitro and in vivo. The in vitro cytotoxicity, apoptosis and cell cycle of CLA-PTX were investigated. The in vitro cellular uptake of CLA-PTX in B16-F10 cells was also analyzed. The antitumor activity of CLA-PTX was also evaluated in B16-F10 tumor-bearing C57BL6/N mice in vivo. The in vitro cytotoxicity results showed that the IC50 of the CLA-PTX is （4.25±0.43） μM, compared with that of （6.70±0.80） μM in PTX treatment group （P〈0.01）. CLA-PTX increased the percentage of total apoptotic cells compared with that of control and PTX treatment groups （P〈0.01）. Compared with untreated cells, CLA-PTX arrested cell cycle progression at the S phase, whereas PTX caused accumulation of cell at GE-M phase both along with the reduction of the cellular fraction arrested at the G1 phase. The amount of cellular uptake of CLA-PTX was significantly higher than that of PTX （P〈0.01）. The in vivo antitumor activity of CLA-PTX was significantly higher than that of control and PTX treatment groups （P〈0.01 or P〈0.05）. In conclusion, our study demonstrated that CLA-PTX has significant antitumor activity in B 16-F 10 cell line.展开更多
With increasing knowledge of the molecular mechanisms of endogenous RNA interference,systemic delivery of small interfering RNA（siRNA） via targeted nanoparticles has emerged as a potential strategy for cancer gene t...With increasing knowledge of the molecular mechanisms of endogenous RNA interference,systemic delivery of small interfering RNA（siRNA） via targeted nanoparticles has emerged as a potential strategy for cancer gene therapy.In this study,a novel formulation[liposome-protamine-chondroitin sulfate nanoparticles（LPC-NP）]was developed for siRNA delivery by self-assembling with charge-charge interaction.The LPC-NP was further modified by DSPE-PEG_（2000） and DSPE-PEG_（2000）-T7 by the post-insertion method.T7,a transferrin-like seven-amino acid peptide,is a targeting ligand for transferrin receptor-overexpressed MCF-7 breast cancer cells.The particle size and zeta potential of LPC-NP were approximately 90 nm and ＋35 mV,respectively. It was shown that PEG modification could significantly decrease aggregation of LPC-NP in serum,and T7 peptide modified LPC-NP could significantly increase the cellular uptake and the gene-silencing effect of siRNA.In vitro cytotoxicity assay exhibited that significant cell growth inhibition was achieved in MCF-7 cells after the delivery of anti-EGFR siRNA.Our encouraging results suggested that T7-modified LPC-NP might be a promising carrier for RNAi-based tumor therapy.展开更多
A new high-performance liquid chromatography （HPLC） method for the quantitative determination of sitagliptin in rat plasma was developed and validated for pharmacokinetics study. The plasma was spiked with the inter...A new high-performance liquid chromatography （HPLC） method for the quantitative determination of sitagliptin in rat plasma was developed and validated for pharmacokinetics study. The plasma was spiked with the internal standard （hydrocortisone, IS）, treated with sodium hydroxide, and extracted with ethyl acetate. The extracted analyte was injected into an Agilent Zorbax Extend-C18 column （250 mm×4.6 mm, 4 μm） maintained at 30℃ and monitored at 267 nm. The mobile phase consisting of methanol-water （60：40, v/v, containing 10 mM Tris and 10 mM triethylamine） was titrated to pH 9.0 using 1 mol/L hydrochloric acid. The flow rate was 1.0 mL/min. The method showed high specificity. Calibration curves of the peak area ratio of each analyte/IS versus sitagliptin concentration were linear in the range of 0.75-100.0μg/mL （r〉0.9957）. The lower limit of quantification （LLOQ） was 0.75 μg/mL. The intra-day and inter-day coefficient of variation was lower than 10%. The accuracy （relative recovery） at three levels was 105.3% （0.75 μg/mL）, 99.8% （10.0 μg/mL） and 99.0% （100.0 μg/mL）. The extraction recovery was 81.5%, 82.4% and 84.5% at the concentrations of 0.75, 10.0 and 100.0 μg/mL, respectively. The short-term, long-term, freeze-thaw storage stability of plasma samples and the stability of standard solutions were satisfactory. This HPLC method is suitable for determining the concentration of sitagliptin in rat plasma and it was applied to determine the concentration-time profiles of sitagliptin in rat plasma following oral administration of sitagliptin.展开更多
Sorafenib is a novel antitumor drug,which is poorly absorbed in the gastrointestinal tract due to its low solubility in water.To improve the bioavailability of sorafenib,a self-microemulsifying drug delivery system(SM...Sorafenib is a novel antitumor drug,which is poorly absorbed in the gastrointestinal tract due to its low solubility in water.To improve the bioavailability of sorafenib,a self-microemulsifying drug delivery system(SMEDDS) formulation of sorafenib was prepared and its relative bioavailability in rats was evaluated.The blank SMEDDS was prepared from a mixture of ethyl oleate(oil phase,20%,w/w),Cremophol EL(surfactant,48%,w/w),PEG-400(co-surfactant,16%,w/w) and ethanol (co-surfactant,16%,w/w).Sorafenib was subsequently dissolved in the blank SMEDDS to obtain a sorafenib SMEDDS formulation with a final sorafenib concentration at 20 mg/mL.The particle size of the emulsified sorafenib SMEDDS was about 20-25 nm. Compared with sorafenib suspension,the prepared SMEDDS formulation exhibited no effect on the T_(max),but significantly increased the AUC,C_(max) and MRT and decreased the drug clearance.Most importantly,the oral bioavailability based on AUC_(0-72h) increased about 25 times after formulating sorafenib in SMEDDS.We concluded that SMEDDS could be a promising vesicle for the oral delivery of the poorly soluble antitumor drug sorafenib.展开更多
A synthetic diblock copolymer poly（2-ethyl-2-oxazoline）-poly（D,L-lactide） （PEOz-PLA） can self-assemble into micelles with an increased efficiency of drug delivery. However, the interactions of blood-micelles and...A synthetic diblock copolymer poly（2-ethyl-2-oxazoline）-poly（D,L-lactide） （PEOz-PLA） can self-assemble into micelles with an increased efficiency of drug delivery. However, the interactions of blood-micelles and cell-micelles remain unclear. In the present study, we aimed to assess the hemocompatibility and cytocompatibility of PEOz-PLA micelles in order to clarify its potentials as carriers for drug delivery. Blood compatibility of the micelles was evaluated by hemolysis analysis, coagulation test, platelet activation investigation and assessment of their interaction with protein. The results revealed that PEOz-PLA micelles had a favorable blood compatibility. In addition, PEOz-PLA micelles showed a good cytocompatibility through SRB assay, presenting only negligible cytotoxicity when incubated with KBv cells. Taken together, PEOz-PLA micelles could be used as a hemocompatible and cytocompatible drug carrier for intravenous administration.展开更多
Oleanolic acid-loaded solid lipid nanoparticles（OA-SLNs）were prepared by using an improved emulsion-solvent evaporation method.The size,zeta potential,encapsulation efficiency,and loading efficiency of OA-SLNs were...Oleanolic acid-loaded solid lipid nanoparticles（OA-SLNs）were prepared by using an improved emulsion-solvent evaporation method.The size,zeta potential,encapsulation efficiency,and loading efficiency of OA-SLNs were（104.5±11.7）nm, （-25.5±1.8）mV,（94.2±3.9）%,and（4.71±0.15）%,respectively.The morphology was illustrated by TEM as sphere stuffed particles.The XRD and DSC spectra confirmed that the OA molecules were dispersed uniformly into SLN matrixes.The results of in vitro release test suggested that OA was released slowly at a rate of 4.88%per hour from SLN preparation,which was consistent with the Zero-order Released Model.In addition,OA-SLNs were stable in artificial gastric juice and artificial intestinal juice.Together,our results provided new data for the potential application of OA-SLNs in oral administration.展开更多
A simple, rapid and sensitive LC-MS/MS method was developed to quantify erlotinib and its active metabolite, OSI-420, simultaneously in BALB/c nude mice plasma. Erlotinib, OSI-420 and propranolol （internal standard）...A simple, rapid and sensitive LC-MS/MS method was developed to quantify erlotinib and its active metabolite, OSI-420, simultaneously in BALB/c nude mice plasma. Erlotinib, OSI-420 and propranolol （internal standard） were extracted from nude mice plasma samples by liquid-liquid extraction. Separation was achieved on a reversed phase ClS column with a mobile phase of acetonitrile-water （35：65, v/v） containing 5 mM ammonium formate （pH = 3.0）. All compounds were monitored by mass spectrometry with electrospray positive ionization. The lower limit of quantification was 0.5 ng/mL for both erlotinib and OSI-420; accuracy was estimated by relative error, which was in the range from 0.07% to 8.00% for erlotinib and -2.83% to 6.67% for OSI-420; precision was validated by relative standard deviation, which was from 2.28% to 15.12% for erlotinib and from 1.96% to 11.50% for OSI-420. This method was applied to a pharmacokinetic study of BALB/c nude mice following oral administration of erlotinib at 12.5 mg/kg. A 2-compartment model was used to fit the pharmacokinetics of erlotinib and 1-compartment model for the pharmacokinetics of OSI-420. The ratio of the active metabolite to parent drug in mice was greater than previously reported in humans and probably reflects interspecies difference in the rate of conversion of erlotinib to OSI-420.展开更多
文摘The clinical pharmacokinetics of ribavirin after a single oral dose of 600 mg ribavirin tablets in healthy Chinese volunteers was studied. A rapid and simple high performance liquid chromatography （HPLC） method was developed to determine the ribavirin concentration in human plasma. C18 column was used for separation with a column temperature of 25℃, the mobile phase was ultrapure water adjusted to pH 3 with acetic acid at the flow rate of 1 mL/min, and the detection wavelength was set at 207 rim. The linear range of the standard curves was 50.4-2016.0 ng/mL and the lower limit of quantification （LLOQ） was 50.4 ng/mL. The relative recoveries of ribavirin were more than 90% in plasma. The RSD of the intra-day precision was less than 10% and that of inter-day was less than 15%. The pharmacokinetic parameters of ribavirin were calculated by WinNonlin. Results indicated that the two-compartment model was a better model for describing the pharmacokinetics profile of ribavirin than one-compartment model. The AUC0-t was 10807.8 h.ng/mL, the CL/F was 64879.5 mL, and the Cmax was 525.1 ng/mL. These results provided the experimental data for the development of ribavirin dosage form.
文摘The sinomenine hydrochloride （SH） patch, a topical drug delivery system, was prepared and characterized. The in vitro release was studied according to the paddle-over-disk method in the appendix of Chinese Pharmacopeia （appendix XD, 2005）. Stability of SH patch was evaluated at accelerated testing conditions （40 ℃, 75% RH）. Pharmacological and pharmacokinetics study were also performed. It was found that the release of SH from patches depended on pH value of the release medium. There were no significant differences between SH patches stored for 6 mon and those stored for 0 mon in the drug content, initial adhesion, lasting stickiness, peeling strength and in vitro release. SH patches exhibited better anti-inflammatory activity as well as analgesic efficacy. More importantly, primary pharmacokinetic parameters of SH patch, such as Cmax and AUC, were much lower than those of SH solution dosed orally. In conclusion, the patch might be a promising delivery system for SH, which bypassed the gastrointestinal tract and was a convenient, efficacious, safe and non-invasive delivery method.
基金National Integrity Innovational Technology Platform of New Drug and Development(Grant No.2009ZX09301- 010)
文摘Clinical drug-drug interactions（DDIs） induced by CYP3A may reduce the exposure and pharmacological activity of CYP3A substrate.Up-regulation of CYP3A mRNA is often used to evaluate inductive effect of test compounds on CYP3A. A quantitative real time PCR assay was developed and validated for the absolute quantification of CYP3A1 and CYP3A2 mRNA.Specific primers of CYP3A1,CYP3A2 and GAPDH（glyceraldehyde-3-phosphate dehydrogenase,as a house-keeping gene） were well designed.The relationship between threshold cycle（Ct） and logarithm of the concentrations of CYP3A1, CYP3A2 and GAPDH was linear ranged from 1 attomol/μL to 1×10~6 attomol/uL with great inter- and intra-assay reproducibility. This method was successfully applied to investigate the time courses of CYP3A1 and CYP3A2 mRNA induction in rat liver after 100 mg/kg dexamethasone（DEX） administration by intraperitoneal（i.p.） injection.The baseline levels of CYP3A1 and CYP3A2 mRNAs were 37.78 attomol/ug（total RNA） and 252.31 attomol/ug（total RNA）,respectively.CYP3A1 and CYP3A2 mRNA values increased gradually to their peak levels（19- and 8- fold vs.baseline） within 24 h and 42 h,respectively,and then returned to their baseline 60 h after DEX administration.
基金National Development of Significant New Drugs(New Preparation and New Technology,Grant No. 2009zx09310-001)the National Basic Research Program of China (973 program,Grant No. 2009CB930300)
文摘Novel mixed polymeric micelles formed by biocompatible polymers,mPEG-PLA and Pluronic P105,were fabricated and used as a nanocarrier to solubilize the poorly soluble anesthetic drug propofol.Propofol was added directly to an aqueous solution of mPEG-PLA/Pluronic P105 mixed micelles and stirred into a micellar solution.The average particle size and size distribution of micelles were evaluated by the dynamic light scattering technology.Drug loading content,encapsulation efficiency and free drug concentration were determined by using ultracentrifugation and lyophilization.In vitro release characteristic of propofol formulation was investigated by dialysis method.The physical stability of mixed micelles was also assessed under storage condition（4 oC） after six months.Sleep-recovery studies in male Sprague-Dawley rats,at a dose of 10 mg/kg were performed to compare the pharmacodynamic profiles of propofol in mixed micelles with that of commercial lipid emulsion（CLE）.The results indicated that solubilization of propofol in the mixed micelles was more efficient than that in mPEG-PLA alone.Micelles with the optimized composition of mPEG-PLA/Pluronic P105/Propofol（10：4：5,w/w/w） had particle size of about 90 nm with narrow distribution（polydispersity index of about 0.2）.The content of free propofol in the aqueous phase of mixed micelles was significantly lower than that in CLE（P〈0.05）.There was no remarkable differences for particle size,polydispersity index,and free drug concentration when the mix micelles were stored at 4 oC for six months,suggesting that the propofol-loaded mixed micelles were stable for at least six months.The accumulative release of mixed micelles was significantly higher than that of CLE at the corresponding time points,suggesting that quick release rate for mixed micelles might produce favorable pharmacological effect.No significant differences in the unconsciousness time and recovery time of righting reflex were observed between the mixed micelles and CLE（P〉0.05）.In conclusion,the mixed micelle of mPEG-PLA and pluronic copolymer may be a promising candidate for intravenous delivery of propofol in clinic.
基金NSFC projects(Grant No.81273455 and 81072597)grants from Ministry of Education(Grant No.NCET-11-0014 and BM U20110263)the funding support from State Key Laboratory of Long-acting and Targeting Drug Delivery System,LUYE PHARMA
文摘In the present work, we aimed to develop alginate-coated chitosan nanoparticles for oral insulin delivery. The N-[（2-hydroxy- 3-trimethylammonium）propyl] chitosan chloride （HTCC） was synthesized, and the quatemized chitosan nanoparticles （HTCC-T NPs） were prepared by ionic gelation of HTCC using tripolyphosphate （TPP）. The alginate-coated quatemized chitosan nanoparticles （HTCC-A NPs） were prepared by coating HTCC-T NPs with alginate （ALG） solution under mild agitation. Particle size, zeta potential, surface morphology, drug loading and entrapment efficiency of HTCC-A NPs were characterized using Zeta-sizer, TEM and HPLC assays. It was found that HTCC-A NPs exhibited uniform spherical particles with the size of （322.2±8.5） nm and positive charges （14.1±0.6） mV. Our data showed that the release behavior of HTCC-A NPs was quite different from that of HTCC-T NPs （without ALG coating） when incubated with various medium at different pH values in vitro, suggesting that ALG coating over the HTCC-T NPs improved the release profile of insulin from the NPs for a successful oral delivery. The ALG coating could also improve the stability of insulin against enzymatic degradation. From circular dichroism spectrum, it was revealed that HTCC-A NPs were capable of maintaining the conformation of insulin. The relative pharmacological bioavailability of HTCC-A NPs was 8.0%±2.5% by intraduodenal administration. The HTCC-A NPs significantly increased （P〈0.05） the relative pharmacological availability （2.2 folds） compared with HTCC-T NPs after oral administration. HTCC-A NPs significantly enhanced the in vivo oral absorption of insulin and exhibited promising potentials for oral delivery.
基金National Natural Science Foundation of China (Grant No.30873170)the National Basic Research Program of China(973 Program 2007CB935800 and 2009CB930300)
文摘Mitochondria are increasingly recognized as important targets for tumor treatment because of their central roles in apoptotic pathways and cellular metabolism. Dichloroacetate （DCA）, a low molecular weight mitochondria-targeting agent, exhibits potential therapeutic effects for tumors. Based on the effects of DCA on tumor cellular metabolism, we carried out this study to investigate the anti-tumor activity of DCA in C6 glioma cells in vitro. The results showed that DCA was able to increase the activity of pyruvate dehydrogenase （PDH）, induce the production of reactive oxygen species （ROS） and reduce the mitochondrial membrane potential （MMP） in C6 ceils in vitro （P〈0.05 or 0.01）, indicating that the anti-tumor effects of DCA in C6 cells could be through the activation of the mitochondrial pathway. In conclusion, mitochondria could be a viable therapeutic target for the treatment of glioma.
基金National Natural Science Foundation of China (Grant No.81172992)the National Basic Research Program of China (973 Program,Grant No.2013CB932501)Innovation Team of Ministry of Education (Grant No.BMU20110263)
文摘Considering the results of our previous research that conjugated linoleic acid mixture-paclitaxel （CLA-mixture-PTX） possesses anti-tumor activity against melanoma and brain glioma, the purpose of this study was to investigate the potential anti-tumor efficacy of cis-9, trans- 1 1-conjugated linoleic acid-paclitaxel （c9, tl 1-CLA-PTX） and trans- 1 O, cis- 12-conjugated linoleic acid-paclitaxel （tl0, c12-CLA-PTX） on MCF-7 breast cancer cell line in vitro and in vivo. The in vitro cytotoxicity, apoptosis induction effect and cell cycle arresting effect of c9, t1 1-CLA-PTX and t10, c12-CLA-PTX were investigated. The in vitro cellular uptake of c9, tl 1-CLA-PTX and tl0, cl2-CLA-PTX in MCF-7 cells were also analyzed. Besides, the anti-tumor activity of c9, tl 1-CLA-PTX and tl0, cl2-CLA-PTX was evaluated in MCF-7 tumor bearing nude mice in vivo. The in vitro cytotoxicity results showed that the value of ICs0 of the tl 0, c l2-CLA-PTX is （0.17±0.02） μM, compared with that of （1.08±0.15） μM in CLA-mixture-PTX and （6.50±1.20） μM in c9, tl 1-CLA-PTX treatment group （P〈0.01）. Both tl0, cl2-CLA-PTX and c9, t l 1-CLA-PTX increased the percentage of total apoptotic cells compared with that of control （P〈0.01）. And the rank of apoptosis induction efficacy was t 10, c 12-CLA-PTX〉CLA-mixture-PTX〉c9, t 11-CLA-PTX （P〈0.01）. Compared with untreated cells, the tl0, c12-CLA-PTX and c9, tl 1-CLA-PTX arrested cell cycle progression at the S and G2-M phase. The amount of cellular uptake of t 10, c 12-CLA-PTX was significantly higher than that of CLA-mixture-PTX （P〈0.01）, which was significantly higher than that of c9, t1 1-CLA-PTX （P〈0.01）. The rank of in vivo anti-tumor activity was tl0, c12-CLA-PTX〉CLA-mixture-PTX〉 c9, t1 1-CLA-PTX （P〈0.01）. In conclusion, our study demonstrated that both tl0, cl2-CLA-PTX and c9, tl 1-CLA-PTX has significant anti-tumor activity in MCF-7 cell line. And while c9, tl 1-CLA-PTX showed weaker inhibitory effect than CLA-mixture-PTX, stronger inhibitory effect was presented by t10, c12-CLA-PTX, which could be a promising alternative for CLA-mixture-PTX.
基金National Natural Science Foundation of China(Grant No.81172992)the National Basic Research Program of China(973 Program,Grant No.2009CB930300)Innovation Team of Ministry of Education(Grant No.BMU20110263)
文摘The purpose of this study was to investigate the potential antitumor efficacy of conjugated linoleic acid-paclitaxel （CLA-PTX） on B16-F10 melanoma cell line in vitro and in vivo. The in vitro cytotoxicity, apoptosis and cell cycle of CLA-PTX were investigated. The in vitro cellular uptake of CLA-PTX in B16-F10 cells was also analyzed. The antitumor activity of CLA-PTX was also evaluated in B16-F10 tumor-bearing C57BL6/N mice in vivo. The in vitro cytotoxicity results showed that the IC50 of the CLA-PTX is （4.25±0.43） μM, compared with that of （6.70±0.80） μM in PTX treatment group （P〈0.01）. CLA-PTX increased the percentage of total apoptotic cells compared with that of control and PTX treatment groups （P〈0.01）. Compared with untreated cells, CLA-PTX arrested cell cycle progression at the S phase, whereas PTX caused accumulation of cell at GE-M phase both along with the reduction of the cellular fraction arrested at the G1 phase. The amount of cellular uptake of CLA-PTX was significantly higher than that of PTX （P〈0.01）. The in vivo antitumor activity of CLA-PTX was significantly higher than that of control and PTX treatment groups （P〈0.01 or P〈0.05）. In conclusion, our study demonstrated that CLA-PTX has significant antitumor activity in B 16-F 10 cell line.
基金National Basic Research Program of China(973 Program,Grant No.2007CB935800 and 2009CB930300)Beijing Natural Science foundation(Grant No.7112089)
文摘With increasing knowledge of the molecular mechanisms of endogenous RNA interference,systemic delivery of small interfering RNA（siRNA） via targeted nanoparticles has emerged as a potential strategy for cancer gene therapy.In this study,a novel formulation[liposome-protamine-chondroitin sulfate nanoparticles（LPC-NP）]was developed for siRNA delivery by self-assembling with charge-charge interaction.The LPC-NP was further modified by DSPE-PEG_（2000） and DSPE-PEG_（2000）-T7 by the post-insertion method.T7,a transferrin-like seven-amino acid peptide,is a targeting ligand for transferrin receptor-overexpressed MCF-7 breast cancer cells.The particle size and zeta potential of LPC-NP were approximately 90 nm and ＋35 mV,respectively. It was shown that PEG modification could significantly decrease aggregation of LPC-NP in serum,and T7 peptide modified LPC-NP could significantly increase the cellular uptake and the gene-silencing effect of siRNA.In vitro cytotoxicity assay exhibited that significant cell growth inhibition was achieved in MCF-7 cells after the delivery of anti-EGFR siRNA.Our encouraging results suggested that T7-modified LPC-NP might be a promising carrier for RNAi-based tumor therapy.
基金National Integrity Innovational Technology Platform of New Drug and Research and Development (Grant No. 2009ZX09301-010)National Fund for Talent Training in Basic Science
文摘A new high-performance liquid chromatography （HPLC） method for the quantitative determination of sitagliptin in rat plasma was developed and validated for pharmacokinetics study. The plasma was spiked with the internal standard （hydrocortisone, IS）, treated with sodium hydroxide, and extracted with ethyl acetate. The extracted analyte was injected into an Agilent Zorbax Extend-C18 column （250 mm×4.6 mm, 4 μm） maintained at 30℃ and monitored at 267 nm. The mobile phase consisting of methanol-water （60：40, v/v, containing 10 mM Tris and 10 mM triethylamine） was titrated to pH 9.0 using 1 mol/L hydrochloric acid. The flow rate was 1.0 mL/min. The method showed high specificity. Calibration curves of the peak area ratio of each analyte/IS versus sitagliptin concentration were linear in the range of 0.75-100.0μg/mL （r〉0.9957）. The lower limit of quantification （LLOQ） was 0.75 μg/mL. The intra-day and inter-day coefficient of variation was lower than 10%. The accuracy （relative recovery） at three levels was 105.3% （0.75 μg/mL）, 99.8% （10.0 μg/mL） and 99.0% （100.0 μg/mL）. The extraction recovery was 81.5%, 82.4% and 84.5% at the concentrations of 0.75, 10.0 and 100.0 μg/mL, respectively. The short-term, long-term, freeze-thaw storage stability of plasma samples and the stability of standard solutions were satisfactory. This HPLC method is suitable for determining the concentration of sitagliptin in rat plasma and it was applied to determine the concentration-time profiles of sitagliptin in rat plasma following oral administration of sitagliptin.
基金The 973 Project(Grant No.2009CB930300)Scientific and Technological Major Special Project -"Significant Creation of New Drugs"(Grant No.2009ZX09310-001).
文摘Sorafenib is a novel antitumor drug,which is poorly absorbed in the gastrointestinal tract due to its low solubility in water.To improve the bioavailability of sorafenib,a self-microemulsifying drug delivery system(SMEDDS) formulation of sorafenib was prepared and its relative bioavailability in rats was evaluated.The blank SMEDDS was prepared from a mixture of ethyl oleate(oil phase,20%,w/w),Cremophol EL(surfactant,48%,w/w),PEG-400(co-surfactant,16%,w/w) and ethanol (co-surfactant,16%,w/w).Sorafenib was subsequently dissolved in the blank SMEDDS to obtain a sorafenib SMEDDS formulation with a final sorafenib concentration at 20 mg/mL.The particle size of the emulsified sorafenib SMEDDS was about 20-25 nm. Compared with sorafenib suspension,the prepared SMEDDS formulation exhibited no effect on the T_(max),but significantly increased the AUC,C_(max) and MRT and decreased the drug clearance.Most importantly,the oral bioavailability based on AUC_(0-72h) increased about 25 times after formulating sorafenib in SMEDDS.We concluded that SMEDDS could be a promising vesicle for the oral delivery of the poorly soluble antitumor drug sorafenib.
基金National Natural Science Foundation of China(Grant No.81172990)the National Key Science Research Program of China(Grant No.973 Program,2009CB930300)+1 种基金Innovation Team of Ministry of Education(Grant No.BMU20110263)the Open Project Program of State Key Laboratory of Drug Delivery Technology and Pharmacokinetics,Tianjin Institute of Pharmaceutical Research
文摘A synthetic diblock copolymer poly（2-ethyl-2-oxazoline）-poly（D,L-lactide） （PEOz-PLA） can self-assemble into micelles with an increased efficiency of drug delivery. However, the interactions of blood-micelles and cell-micelles remain unclear. In the present study, we aimed to assess the hemocompatibility and cytocompatibility of PEOz-PLA micelles in order to clarify its potentials as carriers for drug delivery. Blood compatibility of the micelles was evaluated by hemolysis analysis, coagulation test, platelet activation investigation and assessment of their interaction with protein. The results revealed that PEOz-PLA micelles had a favorable blood compatibility. In addition, PEOz-PLA micelles showed a good cytocompatibility through SRB assay, presenting only negligible cytotoxicity when incubated with KBv cells. Taken together, PEOz-PLA micelles could be used as a hemocompatible and cytocompatible drug carrier for intravenous administration.
基金National Basic Research Program of China(973 Program Grant No.2009CB930300)National Integrity Innovational Technology Platform of New Drug and Research and Development (Grant No.2009ZX09310-001).
文摘Oleanolic acid-loaded solid lipid nanoparticles（OA-SLNs）were prepared by using an improved emulsion-solvent evaporation method.The size,zeta potential,encapsulation efficiency,and loading efficiency of OA-SLNs were（104.5±11.7）nm, （-25.5±1.8）mV,（94.2±3.9）%,and（4.71±0.15）%,respectively.The morphology was illustrated by TEM as sphere stuffed particles.The XRD and DSC spectra confirmed that the OA molecules were dispersed uniformly into SLN matrixes.The results of in vitro release test suggested that OA was released slowly at a rate of 4.88%per hour from SLN preparation,which was consistent with the Zero-order Released Model.In addition,OA-SLNs were stable in artificial gastric juice and artificial intestinal juice.Together,our results provided new data for the potential application of OA-SLNs in oral administration.
基金National Integrity Innovational Technology Platform of New Drug and Development (Grant No. 2009ZX09301-010)Innovation Team of Ministry of Education (Grant No. BMU20110263)
文摘A simple, rapid and sensitive LC-MS/MS method was developed to quantify erlotinib and its active metabolite, OSI-420, simultaneously in BALB/c nude mice plasma. Erlotinib, OSI-420 and propranolol （internal standard） were extracted from nude mice plasma samples by liquid-liquid extraction. Separation was achieved on a reversed phase ClS column with a mobile phase of acetonitrile-water （35：65, v/v） containing 5 mM ammonium formate （pH = 3.0）. All compounds were monitored by mass spectrometry with electrospray positive ionization. The lower limit of quantification was 0.5 ng/mL for both erlotinib and OSI-420; accuracy was estimated by relative error, which was in the range from 0.07% to 8.00% for erlotinib and -2.83% to 6.67% for OSI-420; precision was validated by relative standard deviation, which was from 2.28% to 15.12% for erlotinib and from 1.96% to 11.50% for OSI-420. This method was applied to a pharmacokinetic study of BALB/c nude mice following oral administration of erlotinib at 12.5 mg/kg. A 2-compartment model was used to fit the pharmacokinetics of erlotinib and 1-compartment model for the pharmacokinetics of OSI-420. The ratio of the active metabolite to parent drug in mice was greater than previously reported in humans and probably reflects interspecies difference in the rate of conversion of erlotinib to OSI-420.
