ABSTRACT
Objective@#To evaluate the effect of zinc ions on human umbilical vein endothelial cells biological functions.@*Methods@#The primary human umbilical vein endothelial cells were cultured with the ECM medium, and cells were divided into 8 groups: the control group(routine culture,n=3), 20 μmol/L zinc group(20 μmol/L zinc chloride solution was added into the cell medium, n=3), 40 μmol/L zinc group(40 μmol/L zinc chloride solution was added into the cell medium, n=3),80 μmol/L zinc group(80 μmol/L zinc chloride solution was added into the cell medium, n=3), 100 μmol/L zinc group(100 μmol/L zinc chloride solution was added into the cell medium, n=3), 200 μmol/L zinc group(200 μmol/L zinc chloride solution was added into the cell medium, n=3),300 μmol/L zinc group(300 μmol/L zinc chloride solution was added into the cell medium, n=3), 500 μmol/L zinc group(500 μmol/L zinc chloride solution was added into the cell medium, n=3). The cell proliferation curve was derived from real time cell analysis (RTCA). The viability value was obtained via CCK-8 reagent, and the migration distance was tested by scratch-wound assay while the adhesion function was detected by RTCA.@*Results@#(1)After 18 hours, RTCA showed that the proliferation cell indexes were 4.5±0.6, 3.7±0.4, 3.6±0.3, 2.5±0.4, and 2.5±0.4 in the 20, 40, 80, 100, and 200 μmol/L zinc groups, as compared with 3.5±0.3 in the control group (all P<0.05). Proliferation cell indexes were 0 in both of the 300 μmol/L and 500 μmol/L zinc groups. (2)After 96 hours, the viability were 1.21±0.05, 1.10±0.03, 0.99±0.05, 0.62±0.02, 0.45±0.04, 0.11±0.01, and 0.12±0.06, respectively in the 20, 40, 80, 100, 200, 300, and 500 μmol/L zinc groups, as compared with 0.75±0.05 in the control group (all P<0.05). (3)After 12 hours, the migration distances were (0.56±0.11),(0.96±0.07),(0.49±0.02), and (0.29±0.01)mm in the 20, 40, 80, and 100 μmol/L zinc groups, as compared with (0.24±0.04)mm in the control group (all P<0.05). (4)After 18 hours, the adhesion cell index were 0.40±0.05, 0.31±0.01, 0.38±0.05, and 0.40±0.03 in the 20, 40, 80, and 100 μmol/L zinc groups, as compared with 0.24±0.04 in the control group (all P>0.05).@*Conclusions@#Zinc ions at lower concentration (≤80 μmol/L) can promote proliferation, viability and migration of human umbilical vein endothelial cells, but the adhesion function was not significantly affected by zinc ions. Zinc ions at higher concentration (≥200 μmol/L) can inhibit the cellular function of the human umbilical vein endothelial cells.
ABSTRACT
@#The objectives of this study were to prepare pitavastatin-loaded poly lactic-co-glycolic acid nanoparticles(PLGA), to characterize their pharmaceutical properties, to conduct in vitro drug-release from the nanoparticles, and to observe the effects on the proliferation of endothelial progenitor cells. Both pitavastatin-loaded PLGA and blank PLGA nanoparticles were prepared using emulsion-solvent diffusion method with PLGA being carrier materials. Morphology of the nanoparticles was observed by scanning electron microscopy(SEM), and particle size was analyzed by laser nanometer particle size analyzer. The drug loading and encapsulation efficiency were assayed using high-performance liquid phase. Impact of blank and pitavastatin-loaded nanoparticles on the viability of endothelial progenitor cells was investigated by CCK8 method. Pitavastatin-loaded PLGA nanoparticles exhibited the structure with spherical shape, smooth surface and average diameter of(230. 1±45)nm. The drug loading capacity and encapsulation efficiency were(10. 00±1. 83)% and(35. 54±5. 40)%, respectively. In vitro sustained-release of pitavastatin from the nanoparticles was found. The blank PLGA nanoparticles had no effect on the viability of the endothelial progenitor cells in different concentrations. Compared with pitavastatin group, pitavastatin-loaded nanoparticles(0. 01 μmol/L, 0. 1 μmol/L)had more effects on the proliferation of endothelial progenitor cells. In conclusion, emulsion-solvent diffusion method is applicable in preparation of pitavastatin-loaded PLGA nanoparticles with good shape and sustained-release of interest. Pitavastatin-loaded nanoparticles could significantly improve proliferation of the endothelial progenitor cells.
ABSTRACT
BACKGROUND:The appearance of biodigradable stents brings a new dawn for the fourth coronary intervention revolution. They not only can solve the problem of postoperative acute occlusion of blood vessels, but also can be completely absorbed after a certain time. OBJECTIVE: To summarize the application status of biodegradable coronary stents. METHODS:PubMed, CBM and embase were searched for articles related to biodegradable intravascular stents. RESULTS AND CONCLUSION:Biodegradable polymer stents, biodegradable magnesium stents and biodegradable iron stents are currently the three major research biodegradable stent systems. Numerous clinical trials have demonstrated the long-term safety and reliability of the biological degradation stents, and in the near future they wil replace the existing drug-eluting stents as the primary means of percutaneous coronary intervention. Biodegradable stents currently stil have their limitations, which are reflected in the relationship between mechanical properties and degradation rate and cannot be applied to complicated coronary patients temporarily. It takes 6-12 months to restore normal physiological function of blood vessels, and it can be considered reasonable that degradation of stents is completed in 12-24 months. Poly(lactic-co-glycolic) produced by polylactic acid and polyglycolic acid is currently widely recognized as the stent’s framework. We can get a more appropriate balance between the mechanical properties of the stent and the degradation rate by adjusting the ratio of polylactic acid and polyglycolic acid. This stent not only has good mechanical properties, but also can be completely biodegradable after the restoration of normal function of blood vessels, which has a broad research space.