ABSTRACT
Objective: to prepare neogambogic acid nanoliposomes [GNA-NLC] and study its pharmacokinetics [PK] in rats
Study Design: an experimental study
Place and Duration of Study: mudanjiang Medical University, Mudanjiang, China, from January 2016 to October 2017
Methodology: GNA-NLC was prepared by emulsion evaporation-low temperature solidification. The entrapment efficiency, average particle size, and zeta potential were investigated. Male Wistar rats were injected with 1 mg/mL gambogic acid and GNA-NLC into the caudal vein respectively, and the plasma concentration was determined by UPLCMS/MS. The pharmacokinetic parameters of the two agents were compared
Results: GNA-NLC prepared in this study were mostly spherical spheroids with an average particle size of 146.35 +/- 1.72 nm, polydispersity coefficient of 0.26 +/- 0.02, zeta potential of -28.24 +/- 0.13 MV, entrapment efficiency of 84.63%, and drug loading capacity of 4.23%. DSC showed that neogambogic acid nanoparticles had formed and neogambogic acid was amorphous in the matrix. The pharmacokinetics results in rats showed that GNA-NLC plasma concentration was significantly higher than that of common preparation of gambogic acid, with a half-life period of 10.14 +/- 0.03 hours, 4.57 times that of gambogic acid. AUC0 - 24hof gambogic acid in GNA-NLC lipidosome was 58.36 +/- 0.23 [micro]g/h/mL, 4.83 times that of gambogic acid
Conclusion: GNA-NLC can be prepared successfully by emulsion evaporation-low temperature solidification. The method is simple and easy to control. The GNA-NLC has a long cycle, and high blood concentration, sustained release compared with the raw material gambogic acid
ABSTRACT
The use of optimal regulatory sequences for simultaneous expression of the transgenes might play a significant role in engineering plants with increased disease and insect resistance.The plant expression vector pOMS-GUS,which contained the GUS gene under the control of a chimeric promoter based upon the mannopine synthase(mas)promoter and the octopine synthase(ocs)enhancer,was constructed.Used as control,another vector pMAS-GUS,carried the GUS gene driven by only the mas promoter.The two vectors were introduced into tobacco plants by Agrobacterium-mediated transformation.Fluorometric assays for GUS activity and reverse transcription-polymerase chain reaction(RT-PCR)analysis revealed that GUS gene expressed weakly with untreated transgenic tobacco while the level of GUS activity increased steadily after 1 h subjected to wounding.The expression of the mas and ocs/mas promoters was induced a further 1.8-fold and 5.7-fold,respectively.SA(1 mmol/L)or MJ(250 ?mol/L)treatment also caused a large induction of the ocs/mas chimeric promoter;And the application of SA in combination with MJ(1 mmol/LSA & 250 ?mol/L MJ)produced an additive effect that exceeded the wounding response.The results showed that the ocs/mas chimeric promoter is a strong inducible promoter that can be activated by various stresses.The chimeric promoter should have utility in development of disease and insect resistant transgenic crops.