ABSTRACT
ObjectiveTo investigate the effects of hydroxycamptothecin liposomes （LHCPT） on myocardial fibrosis in rats with heart failure by regulating the sphingosine kinase 1 （SphK1）/sphingosine-1-phosphate （S1P） signaling pathway. MethodsSD rats were divided into control group， model group， hydroxycamptothecin （HCPT） group， LHCPT group， captopril group， and LHCPT+K6PC-5 （SphK1 activator） group， with 12 rats in each group. The heart failure rat models in all groups except the control group were established by intraperitoneal injection of doxorubicin and then the corresponding drugs were given once a day. After four weeks， we applied color Doppler ultrasound to detect left ventricular end systolic diameter （LVESD）， left ventricular end diastolic diameter （LVEDD）， and left ventricular ejection fraction （LVEF） in rats； HE and Masson staining for myocardial pathological damage and myocardial fibrosis in rats， respectively； ELISA method for the levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in rat myocardial tissues； qRT-PCR for the expression of transforming growth factor-β1 （TGF-β1）， type I collagen （Collagen I）， and type Ⅲ collagen （Collagen Ⅲ） in rat myocardial tissues； Western blot for the expression of SphK1 and S1P proteins in rat myocardial tissues. ResultsCompared with the control group， the model group showed severe myocardial pathological damage and myocardial fibrosis， increased LVESD， LVEDD， levels of TNF-α and IL-6， expression of TGF-β1， Collagen I， Collagen Ⅲ， SphK1， S1P and decreased LVEF （P<0.05）. Compared with the model group， the HCPT group， LHCPT group and captopril group showed alleviated myocardial pathological damage and myocardial fibrosis， decreased LVESD， LVEDD， levels of TNF-α and IL-6， expression of TGF-β1， Collagen I， Collagen Ⅲ， SphK1， S1P and increased LVEF （P<0.05）. Compared with the LHCPT group， the LHCPT+K6PC-5 group showed aggravated myocardial pathological damage and myocardial fibrosis， increased LVESD， LVEDD， levels of TNF-α and IL-6， expression of TGF-β1， Collagen I， Collagen Ⅲ， SphK1， S1P and decreased LVEF （P<0.05）. ConclusionLHCPT may inhibit myocardial fibrosis in heart failure rats by inhibiting the SphK1/S1P signaling pathway.
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Objective: To prepare microcapsules for controlled release of 10-hydroxycamptothecin (HCPT), and determine its encapsulation efficiency and drug release profile in vitro. Methods: The microcapsules loaded with HCPT were prepared using a novel coating technology based on the layer-by-layer (LBL) deposition of oppositely charged polylysine (PLL) and alginate (ALG) polyelectrolytes with good biocompatibility onto microcrystal templates. Results: The microcapsules fabricated by this method had visible core-shell structure observed by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM); The entrapment efficiency of the microcapsules was as high as (68.41 ± 0.72)%; The release rate of HCPT decreased as the bilayers increased in vitro. Conclusion: The microcapsules of HCPT prepared by LBL have higher entrapment efficiency and are characterized with controlled drug release, which has potential for future application.
ABSTRACT
<p><b>BACKGROUND</b>Enhanced apoptosis of cytotrophoblasts in early pregnancy is associated with high risk of intrauterine growth retardation and preeclampsia, which are two common pregnant complications. Its etiological factors remain unclear. Cytotrophoblasts share some traits with innate immune cells and may show response to lipopolysaccharide. This study was conducted to demonstrate whether lipopolysaccharide has apoptosis-inducing effects on cytotrophoblast and the role of innate immune reaction in this process.</p><p><b>METHODS</b>Cytotrophoblasts were isolated from early pregnant villous tissues and cultured with serum-free medium. Subsequently, cytotrophoblasts were treated with lipopolysaccharide at the concentrations of 0 (control), 25, 50, 100 and 200 ng/ml for 24 hours. Apoptosis of cytotrophoblasts was determined by light microscopy, Hoechst 33258 DNA staining with a fluorescent microscope, transmission electron microscope and annexin V-fluorescein isothiocyanate-conjugated/propidium iodide (PI) staining with flow cytometry. Then expression of caspase-3 was detected by Western blot. Confocal immunofluorescence technique was used to detect tumor necrosis factor alpha expression in cytotrophoblasts. The levels of tumor necrosis factor alpha in the culture medium were detected by enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>Under light, fluorescence microscope and transmission electron microscope, characteristic alternations of apoptosis in cytotrophoblasts were observed after lipopolysaccharide treatment. Flow cytometry results showed that lipopolysaccharide significantly increased apoptosis indexes of cytotrophoblasts. Significant statistical differences were found in the above groups (P = 0.01). The mean relative densities of bands corresponding to caspase-3 were significantly increased in groups treated with lipopolysaccharide, as compared with the normal control (P < 0.001). Tumor necrosis factor a expression was found to increase in cytotrophoblasts by confocal immunofluorescence technique and in culture medium by enzyme-linked immunosorbent assay after lipopolysaccharide treatment. A positive correlation was found between tumor necrosis factor a expression and apoptosis indexes of cytotrophoblasts (r = 0.747, P < 0.001).</p><p><b>CONCLUSION</b>Apoptosis of cytotrophoblasts could be induced by lipopolysaccharide, in which innate immune reaction is the important mechanism.</p>
Subject(s)
Humans , Apoptosis , Blotting, Western , Cells, Cultured , Dose-Response Relationship, Drug , Flow Cytometry , Immunity, Innate , Lipopolysaccharides , Pharmacology , Microscopy, Confocal , Trophoblasts , Cell Biology , Tumor Necrosis Factor-alpha , PhysiologyABSTRACT
Objective To investigate the expression of peroxisome proliferators-activated receptor ? (PPAR?) in trophoblast and relation between PPAR? ligands and trophoblast invasion.Methods We examined the expression of PPAR? by immunohistochemistry,immunocytochemistry and real time quantitative PCR.We next examined,using the cytotrophoblast culture model,the biological role of PPAR? ligands in vitro.Results PPAR? was mainly localized in the nuclei of villous cytotrophoblast and extravillous cytotrophoblast of cell islands and cell columns.In villous tissue and cultured trophoblast from early first trimester,the level of expression of PPAR? mRNA and protein was 36.0?5.1,13.4?3.1 and 1.35?0.08,1.13?0.11;from late first trimester it was 23.3?5.5,6.1?1.3 and 1.17?0.03,0.86 ?0.05,and the expression of PPAR? was obviously decreased (P