RESUMEN
Objective To optimize the preparation technology of transcription activator (TAT) and polyethylene glycols (PEG) co-modified tilianin-loaded composite phospholipid liposome (TAT & PEG tilianin CPL, T&PTCPL) and investigate its protective effect on cardiomyocytes. Methods The composite phospholipid liposome was prepared by thin film-ultrasonic method. A three- factor, three-level Box-Behnken experimental design was employed. The weight ratio of total phospholipid to tilianin (X1), the concentration of DSPE-PEG2000-TAT (X2), and hydration volume (X3) were observed. The encapsulation efficiency (Y1), particle size (Y2), and polydispersion coefficient (Y3) were evaluated to optimize optimal formula. In addition, hypoxia/reoxygenation model was established with Na2S2O4 in H9C2 cells. Superoxide dismutase (SOD) activity, malonaldehyde (MDA) level and release of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) were assessed to evaluate the effect of T&PTCPL, meanwhile, the in vitro release rate (dynamic dialysis method) and absorption rate of tilianin and T&PTCPL in Caco-2 cell were examined. Results The optimal formula was as following: X1 = 20, X2 = 1.7%, and X3 = 3.2 mL; The encapsulation efficiency was (86.62 ± 2.51)%, particle size was (149.7 ± 8.2) nm and PDI was 0.15 ± 0.05. Compared with model group, T&PTCPL and tilianin groups increased SOD activity, inhibited level of MDA, LDH and CK-MB leakage (P < 0.05), and the effect of T&PTCPL group was better than tilianin group, meanwhile, T&PTCPL was completely released at 48 h, with a cumulative release of 88.65%, and Caco-2 cells had better absorption of T&PTCPL. Conclusion The Box-Behnken design is suitable for optimizing the formulation of T&PTCPL, and the observed responses are in close agreement with the predicted values of the mathematic models; Moreover, T&PTCPL shows a better sustained release effect in vitro release, which promots the absorption of tilianin in Caco-2 cells and suggests that T&PTCPL may have protective effect on myocardial ischemia reperfusion injury.
RESUMEN
OBJECTIVE: To investigate the brain pharmacokinetics of co-modified liposomes of α-cobrotoxin in rats after intranasal administration. METHODS: DSPE-PEG2000-Pep1 and DSPE-PEG2000-Pep2 were synthesized by Michael addition reaction. And their structures were verified by proton nuclear magnetic resonance spectroscopy (1H-NMR) and infrared spectroscopy (FTIR). Pep2(Pep1)-αCT-LP was prepared by the method of thin-film hydration and post-inserting, then its morphology, particle size, and Zeta potential were investigated. The encapsulation efficiency of liposomes was determined by ultrafiltration centrifugal method. The concentrations of αCT-LP, Pep1-αCT-LP, Pep2-αCT-LP, and Pep2(Pep1)-αCT-LP in periaqueductal gray (PAG) after intranasal administration were measured by microdialysis and the pharmacokinetical parameters were analyzed by PKSolver software. RESULTS: The structures of DSPE-PEG2000-Pep1 and DSPE-PEG2000-Pep2 were proved by 1H-NMR and FTIR. The prepared Pep2(Pep1)-αCT-LP was nearly spherical with uniform size, the mean particle size was (115.8±1.86) nm, and the Zeta potential was (-13.77±0.75) mV. Besides, the encapsulation efficiency was (32.75±1.12)%. The RESULTS ofin vivo test demonstrated that the αCT concentrations in PAG after intranasal administration of Pep2(Pep1)-αCT-LP were significantly increased compared with the groups of αCT-LP, Pep1-αCT-LP and Pep2-αCT-LP(P<0.05). Theρmax, tmax, and AUC0→∞ were (244.72±3.15) ng·mL-1, (88.01±4.19) min, (89 199.02±1 922.99) ng·min·mL-1, respectively. CONCLUSION: Pep2(Pep1)-αCT-LP can significantly increase the concentrations of αCT in periaqueductal gray, which provides a promising method for development of polypeptide agents for brain-targeting.