ABSTRACT
Objective To investigate the uptake mechanism of HepG2.2.15 cells to the nanoparticles co-loaded with syringopicroside and hydroxytyrosol (SH-NPs). Methods The nanoparticles were prepared by using a nanoprecipitation method with mPEG-PLGA as nano-carrier co-loaded with syringopicroside and hydroxytyrosol. The uptake mechanism of HepG2.2.15 cells to SH-NPs was studied by fluorescence microscopy and flow cytometry using fluoresceineisothiocyanate (FITC) as a fluorescent marker. Results With colchicine as the inhibitor, the incubation time ranged from 0.5 to 24 h, the percentage of positive cells increased from 1.9% to 56.4%; When the drug concentration was 125, 250 μg/mL and 500 μg/mL, the positive cell percentages were 4.9%, 3.4% and 3.9%. With chloroquine as the inhibitor; the incubation time ranged from 0.5 to 24 h, the percentage of positive cells increased from 7.4% to 55.4%; When the drug concentration was 125, 250 and 500 μg/mL, the percentage of positive cells was 19.5%, 22.5% and 27.6%. Conclusion Colchicine and chloroquine have an inhibitory effect on HepG2.2.15 cells uptake, and the uptake of SH-NPs in HepG2.2.15 cells was positively correlated with drug concentration and incubation time. It can be concluded that the uptake mechanism of HepG2.2.15 cells to SH-NPs was nonspecific adsorption endocytosis.
ABSTRACT
Four crystalline forms of clopidogrel bisulfate were characterized by analytical techniques. Aiming to research the absorption characteristics of clopidogrel bisulfate polymorphs after taken orally by rat, and to estimate the influence of crystal form to pharmacodynamic action, four crystalline forms of clopidogrel bisulfate were administered intragastrically to rats, and high performance liquid chromatography (HPLC) was used to measure the contents of clopidogrel bisulfate and its metabolite in rat plasma. The metabolite of clopidogrel bisulfate was detected in rat plasma. There were significant deviations among four crystalline forms in the areas under curve of the metabolite of clopidogrel bisulfate. We concluded that the different crystal forms of clopidogrel bisulfate showed different pharmacokinetic characteristics, which might affect pharmacodynamic action.