Animals ; Cations ; chemistry ; Chitin ; administration & dosage ; analogs & derivatives ; chemistry ; Chitosan ; DNA ; administration & dosage ; Gene Transfer Techniques ; Genetic Therapy ; Liposomes ; administration & dosage ; chemistry ; Polylysine ; administration & dosage ; chemistry

OBJECTIVE: To compare the efficiency of intra-arterial, intraportal, and intravenous administration of cationic lipid emulsion/DNA complex, as used for gene transfer to rat liver. MATERIALS AND METHODS: DNA-carrier complex for the in-vivo experiment was prepared by mixing DNA and a cationic lipid emulsion. According to the administration route used (intra-arterial, intraportal, or intravenous), the animals were assigned to one of three groups. The heart, lung, liver, spleen and kidneys were removed and assayed for total protein and luciferase concentration. RESULTS: The cationic lipid emulsion/DNA complex used successfully transfected the various organs via the different administration routes employed. Luciferase activity in each organ of untreated animals was negligible. Liver luciferase values were significantly higher in the groups in which intra-arterial or intraportal administration was used. CONCLUSION: The intra-arterial or intraportal administration of cationic lipid emulsion/DNA complex is superior to intravenous administration and allows selective gene transfer to the liver.
Animal ; Catheterization ; Cations/*administration & dosage ; Comparative Study ; DNA/*administration & dosage/genetics ; Emulsions/administration & dosage ; Gene Transfer Techniques ; Injections, Intra-Arterial ; Injections, Intravenous ; Lipids/*administration & dosage/genetics ; Liver/*metabolism ; Rats ; Rats, Sprague-Dawley

The efficiency and safe range of Lipofectamine2000 (LF2000)/bcl-xl applied in human keratocytes, the optimal ratio of LF2000/bcl-xl and the bcl-xl gene expression in human keratocytes were investiaged. By using trypan-blue staining, the effects of LF2000 and bcl-xl on the survival rate of the cultured human keratocytes were measured respectively. By using semi-quantitative RT-PCR, the efficiency and the expression of LF2000-mediated bcl-xl transfection into keratocytes were examined. The results showed that the survival rate of human keratocytes had no signficant change in the presence of LF2000 (20 microg/ml) or bcl-xl (10 microg/ml) for 24 h. LF2000 could effectively mediate the transfection of exogenous gene bcl-xl into human keratocytes. The best transfection efficiency could be obtained when the ratio of bcl-xl/LF2000 was 1:8. One day after transfection, the positive cells for bcl-xl could be detectable, and the positive rate reached the peak-on the posttransfection day 3 (48.3%), then gradually decreased. Fifteen days after transfection, there were few positive cells. It was suggested that LF2000 could effectively transfer the exogenous gene bcl-xl into human keratocytes without obvious toxicity during a concentration range. LF2000/bcl-xl may be likely to play an important role in gene therapy of human keratocytes.
Cations/administration & dosage ; Cornea/cytology ; Gene Therapy ; Keratinocytes/cytology ; Keratinocytes/*metabolism ; Liposomes ; Transfection ; bcl-X Protein/biosynthesis ; bcl-X Protein/*genetics

AIMTo construct a liposomal liver targeting delivery system by adding soybean-derived sterylglucoside (SG) to the cationic liposomes.

METHODSThe physico-chemical properties of SG modified cationic lipsomes were investigated using fluorescein sodium (FS) as a model drug, as well as the interaction of SG modified liposomes with HepG2 2. 2. 15 cells in the point of involvement of asialoglycoprotein receptor (ASGP-R) mediated transfection. Liver targeting of modified cationic liposomes were also investigated using liver perfusing technique, and hepatocytes and non-hepatocytes were separated and examined after perfusing.

RESULTSAll the formula yielded high incorporation efficiency (83.12% - 91.74%), small particle size (93.0 - 124.4 nm). The zeta potential of blank liposomes all showed positive values. The transfection efficiency of FS entrapped in SG-liposomes with HepG2 2.2. 15 was significantly higher than that of liposomes without modification. The transfection of SG-liposomes were reduced significantly by the 20/30 mmol galactose as a competitor of ASGP-R. All the cationic liposomes showed high level of liver uptake of FS. Compared with the uptake of non-hepatocytes of each respectively, only SG/Brij-35 liposomes showed difference in FS uptake by hepatocytes (P < 0.05).

CONCLUSIONIt showed that SG/Brij-35 modified cationic liposomes are potentially useful drug carrier to liver but may be affected by different modification.

Animals ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cations ; pharmacokinetics ; Cell Line, Tumor ; Cholestenes ; administration & dosage ; pharmacokinetics ; Drug Delivery Systems ; Galactose ; pharmacology ; Humans ; Liposomes ; Liver ; metabolism ; Liver Neoplasms ; metabolism ; pathology ; Male ; Particle Size ; Polyethylene Glycols ; administration & dosage ; pharmacokinetics ; Rats ; Transfection

AIMTo prepare lung targeting azithromycin cationic liposomes and to observe its tissue distribution in mice.

METHODSThe azithromycin cationic liposomes were prepared by thin film method with freeze-thawing steps. HPLC method was established and validated for the determination of azithromycin in tissues of mice.

RESULTSThe particle size of the liposomes was 6.582 microm with zeta potential of +19.5 mV. The entrapment efficiency was more than 75%. The liposomes was stable in 6 months stored at 4 degrees C. The release in vitro was characterized by Higuchi equation. Azithromycin liposomes and free azithromycin solution were injected intravenously at a dose of 80 mg x kg(-1) to mice. Compared with solution, liposomes were characterized by slower clearance, increased half-life and the AUC increased by 7.4 fold in lung.

CONCLUSIONThin film method with freeze-thawing steps could increase the entrapment efficiency and increase the particle size of azithromycin liposomes. After modification of lipid membrane with stearylamine, the cationic liposomes were prepared. The azithromycin concentration and AUC increased in lung after iv administration to mice of the cationic liposomes. This offered a good information for preparing liposomes targeting on the lung.

Animals ; Anti-Bacterial Agents ; administration & dosage ; chemistry ; pharmacokinetics ; Area Under Curve ; Azithromycin ; administration & dosage ; chemistry ; pharmacokinetics ; Cations ; Drug Carriers ; Drug Compounding ; methods ; Drug Delivery Systems ; Female ; Liposomes ; Lung ; metabolism ; Male ; Mice ; Particle Size ; Tissue Distribution

Despite recent advances in conventional therapeutic approaches for cancer, the efficacy of chemotherapy for cancer is limited due to the drug resistance and toxic side effects during treatment. To overcome drug resistance, higher doses of the toxic chemotherapy drugs are frequently administered, thus leading to even severe adverse side effects, which have limited their clinical application. Cationic liposome as a novel non-viral carrier for co-delivery of gene and chemotherapy drugs in cancer gene therapy has already attracted more and more attention in recent years. Most importantly, this combined strategy can generate a significant synergistic effect, which can silence the related gene expression and increase the concentration of the intracellular chemotherapy drugs. This approach allows the use of a much lower dose of the chemotherapy drugs to achieve same therapeutic effect, which may have the potential for overcoming some major limitations of the conventional chemotherapy. In conclusion, co-delivery of gene and chemotherapy drugs with cationic liposome delivery system will play a vital role in the future and especially could be a promising clinical treatment for drug-resistant tumors.
Animals ; Antineoplastic Combined Chemotherapy Protocols ; administration & dosage ; therapeutic use ; Cations ; Cell Line, Tumor ; DNA ; administration & dosage ; genetics ; Drug Carriers ; Drug Delivery Systems ; Gene Transfer Techniques ; Genetic Therapy ; methods ; Humans ; Liposomes ; administration & dosage ; chemistry ; Neoplasms ; therapy ; RNA, Small Interfering ; administration & dosage ; genetics

The purpose of study was to investigate the feasibility of the application of cationic propyl gallate (C-PG) as inducer of platelet aggregation for evaluating the platelet function of single-donor plateletpheresis and identifying the incidence of defective platelet function among donors. Experiments were as follows: 3 healthy volunteers' platelet aggregation induced by 100-300 micromol/L C-PG was determined by LG-PABER analyzer to observe the effect of C-PG concentration on platelet aggregation; 30 healthy volunteers' platelet aggregation before and 24 hours after administration of 200-400 mg acetylsalicylic acid (ASA) was examined after induction by 200 micromol/L C-PG for determining the cut-off value to discriminate platelet dysfunction donors; the platelet aggregation of 483 platelet donors was detected and the activated plasma clotting time (APCT) of donors who have deficiency in platelet aggregation was examined for investigating the incidence of defective platelet function among donors. The results showed that platelets were activated by C-PG induction in a dose dependent manner, when concentration of C-PG reached 200 micromol/L, the percentage of platelet aggregation was highest. It significantly decreased after 24 hours with ASA than that before the administration (P < 0.001), especially in 180 seconds induced by C-PG. If cut-off point was fixed on the platelet aggregation < 20% in 180 seconds, donors of platelet dysfunction can be selected effectively. 25 of defective platelet aggregation function among 483 donors were detected, and 11 out of 25 platelet dysfunction donors had the deficiency in procoagulant activity with prolonged APCT. It is concluded that C-PG as inducer of platelet aggregation is feasible to screen the platelet function of donors. Five percent of platelet donors has function defect examined by C-PG as inducer of platelet aggregation.
Antioxidants ; chemistry ; pharmacology ; Aspirin ; administration & dosage ; Blood Donors ; Blood Platelets ; cytology ; drug effects ; physiology ; Cations ; chemistry ; Humans ; Platelet Activation ; drug effects ; Platelet Aggregation ; drug effects ; Platelet Aggregation Inhibitors ; administration & dosage ; Platelet Function Tests ; Platelet Transfusion ; Propyl Gallate ; administration & dosage ; chemistry ; Whole Blood Coagulation Time