Objective Investigate the relation between decrease of apoptosis caused by delayed preconditioning and expression of SMAC and XIAP.Methods Sprage-Dawleyt rats were divided into four groups: control,sham,I/R and IPC/SWOP.The rats in I/R group underwent ischemia for 1 hour by classic artery ligation and reperfusion for 1 hour.The rats in IPC/SWOP group underwent tree cycles of 5-minute ischemia and 5-minute reperfusion 24 hours prior to the index occlusion.Cell apoptosis was measured by flow cytometry,the activity of caspase-3 was also measured.The expression of SMAC and XIAP in cytosol of myocardial cell was measured by Western blot.Results Cell apoptosis rate,activity of caspase-3 and expression of SMAC significantly increased in I/R as compared with control(P

Objective To simulate local hemodynamic factors at particular arterial positions.Method A combination of high-lipid diet and immuoreactive injury was used to establish a hyperlipemia and atherosclerosis model in rabbit.Serrial sections were analysed by OLYSIA software.Data of caliber at different positions of carotid bifurcation,areas and circumference and thickness of the atherosclerotic plaque at carotid bifurcation were obtained and to establish a geometric model of rabbit carotid artery bifurcation with Gambit software.Wall shear stress distribution of the carotid sinus were analysed by numerical simulation.Result 1) A geometric model of rabbit carotid artery bifurcation was obtained.2) The wall shear stress of the carotid sinus of the atherosclerosis(AS) model group was found to be lower than that of the control group at shear rate 128.5 S~(-1).The lowest wall shear stress of the control was 4.028 times that of the AS model.Conclusion Low wall shear stress is a risk hemodynamic factor in the development of atherosclerotic plaque.

Objective:To investigate the effect of Superfine Cordyceps militarisv Powder on the immune functions of the mice,and to provide basis for improving the utilizable ratio of Cordyceps militaris.Methods:A total of 40 mice were randomly divided into negative control group,low dose (0.166 5 g·kg-1),middle dose (0.333 3 g·kg-1),and high dose (0.999 9 g·kg-1) of Superfine Cordyceps militaris Powder groups,and there were 10 mice in each group.The mice in different doses of Superfine Cordyceps militaris Powder groups were administered with the Superfine Cordyceps militaris Powder for 30 d by intragastric infusion respectively,whereas,the mice in negative control group were administered with the same volume of water for 30 d by intragastric infusion.The body weights,the spleen indexes and thymus indexes of the mice in various groups were measured;the lymphocyte transformation abilities of the mice in various groups were observed by lymphocyte transformation experiment;the levels of delayed-type hypersensitivity reaction of the mice were examined with toe incrassation;the number of antibody forming cells,phagocytic rate and phagocytic index of chicken erythrocytes phagocytized by peritoneal macrophages of the mice were detected.Results:Compared with negative control group,the body weights,the spleen indexes a nd thymus indexes of the mice in different doses of Superfine Cordyceps militaris Powder groups had no significant differences (P>0.05).The lymphocyte transformation abilities of the mice in middle and high doses of Superfine Cordyceps militarisPowder groups were higher than that in negative control group(P<0.05).The levels of delayed-type hypersensitivity reaction of the mice in middle and high doses of Superfine Cordyceps militaris Powder groups were higher than those in low dose of Superfine Cordyceps militaris powder group and negative control group(P<0.05).The numbers of antibody forming cells of the mice in low,middle and high doses of Superfine Cordyceps militaris Powder groups were higher than that in negative control group(P<0.05).The phagocytic rates and phagocytic indexes of chicken erythrocytes phagocytized by peritoneal macrophage of the mice in low,middle and high doses of Superfine Cordyceps militaris Powder groups were higher than that in negative control group(P<0.05).Conclusion:Superfine Cordyceps militaris Powder can strengthen the immune functions of the mice,and the recommended doses are 0.333 3 and 0.999 9 g·kg-1.

This study aimed to characterize and magnetic resonance imaging (MRI) track the mesenchymal stem cells labeled with polylysine-coated superparamagnetic iron oxide (PLL-SPIO). Rat bone marrow derived mesenchymal stem cells (rMSCs) were labeled with 25, 50 and 100 microg/mL PLL-SPIO for 24 hours. The labeling efficiency was assessed by iron content, Prussian blue staining, electron microscopy and in vitro MR imaging. The labeled cells were also analyzed for cytotoxicity and differentiation potential. Electron microscopic observations and Prussian blue staining revealed that 75% -100% of cells were labeled with iron particles. PLL-SPIO did not show any cytotoxicity up to 100 microg/mL concentration. Both 25 microg/mL and 50 microg/mL PLL-SPIO labeled stem cells did not exhibit any significant alterations in the adipo/osteo/chondrogenic differentiation potential compared to unlabeled control cells. The lower concentration of 25 microg/mL iron labeled cells emitted an obvious dark signal in T1W, T2WI and T2 * WI MR image. The novel PLL-SPIO enables to label and track rMSCs for in vitro MRI without cellular alteration. Therefore PLL-SPIO may potentially become a better MR contrast agent especially in tracking the transplanted stem cells and other cells without compromising cell functional quality.
Animals ; Bone Marrow Cells ; Cell Differentiation ; Dextrans ; chemistry ; Magnetic Resonance Imaging ; Magnetite Nanoparticles ; chemistry ; Mesenchymal Stromal Cells ; cytology ; Polylysine ; chemistry ; Rats ; Staining and Labeling

The oral administration of bioactive macromolecular drugs such as proteins, peptides and nucleic acids represents unprecedented challenges from the drug delivery point of view. One key consideration is how to overcome the gastrointestinal tract absorption barrier. Recent studies suggest that microfold cell (M cell), a kind of specialized antigen-sampling epithelial cell which is characterized by a high endocytic rate and low degradation ability, may play an important role in macromolecule oral absorption. The development of an in vitro M cell coculture system and its modified models greatly advanced the study of M cells and the development of oral delivery system for macromolecular drugs. The special structure, function and formation characteristics, and biomarkers of M cell are summarized in this review. The applications of in vitro M cell models in developing oral delivery system ofbioactive macromolecular drugs are discussed.

AIM: To observe the effects of miR-542-5p on the proliferation of rat small intestine crypt epithe-lial IEC-6 cells induced by sphingosine-1-phosphate (S1P).METHODS: Two IEC-6 cell lines (SphK1-IEC-C1 and SphK1-IEC-C2) were established, which expressed sphingosine kinase-1 (SphK1) stably.Radioactive tracer was used to detect SphK1 activity and S1P secretion.The cell proliferation was observed by cell counting and described by drawing growth curve, and the cell cycle analysis was carried out by flow cytometry.The level of miR-542-5p was evaluated by RT-qPCR.RESULTS: Compared with control vector cells without SphK1 cDNA, both SphK1-IEC-C1 and SphK1-IEC-C2 cell lines showed that Sphk1 was elevated, both intracellular and extracellular S1P increased dramatically, the rate of cell growth was faster, the percentage of the cells in S phase increased, and miR-542-5p expression decreased.S1P (0.5~10 μmol/L) led to the decrease in miR-542-5p expression.On the contrary, SphK1 silencing resulted in the increase in miR-542-5p expression in the IEC-6 cells.The miR-542-5p was elevated in SphK1-IEC-C1 cells and SphK1-IEC-C2 cells, which caused the decrease in the percentage of the cells in S phase.The cell growth rate in the above-mentioned 2 cell lines decreased compared with negative control group.CONCLUSION: In IEC-6 cells, S1P promotes proliferation by inhibiting miR-542-5p expression, which induces the cell cycle transferring from G1 phase to S phase.

Objective To optimize the extraction process for the polysaccharide from fermented Cordyceps Sinensis powder with response surface methodology.Methods We selected the factors and levels on the basis of single factor experiment,and then designed the experiment with 3 factors and 3 levels based on the principle of Box-Behnken's design.Results The effect of the factors of extraction temperature,time and solid-liquid ratio on extraction ratio was in decreasing sequence.The optimal extraction technology obtained through the classical analysis was as follows:extraction temperature at 95 ℃,the ratio of solid to liquid being 1 ∶ 21,and extraction for 73 min.Under this condition the theoretical extraction rate was 4.31％ and the actual extraction rate was (4.20 ± 0.1)％.Conclusion The obtained values agree with the predicted values of the mathematic models,and the Box-Behnken experimental design is suitable for optimizing the extraction of the polysaccharide from fermented Cordyceps Sinensis powder.

Fluid shear stress plays a key role in many physiological activities and pathological processes of the cardiovascular diseases. In vivo, endothelial cells (ECs) are constantly exposed to hemodynamic force which can modulate structure and function of ECs. Previous studies have demonstrated that IL-8 protein production in endothelial cells was modulated by fluid shear stress, and IL-8 protein production induced by fluid shear stress was time-dependent. In order to identify the role of intensity of fluid shear stress on IL-8 protein production of human umbilical vein endothelial cells (HUVECs), we had HUVECs exposed to shear stress 2.09, 4.61, 6.19, 8.51, 10.50, 12.59, 14.41, 17.22, 18.32 dyne/cm2 respectively and employed quantitative sandwich enzyme-linked immunosorbent assay (ELISA) to measure the IL-8 protein. Here we show that HUVECs untreated with fluid shear stress secreted very little IL-8 in culture media. The IL-8 protein production induced by shear stress was force intensity-dependent. After HUVECs being subjected to low fluid shear stress (2.09 dyne/cm2) for 5 h or 6 h, IL-8 protein production increased and was nearly 6 times or 7 times over that of HUVECs subjected to high fluid shear stress (18.32 dyne/cm2). The linear regression equations between IL-8 protein production (y) and shear stress (dyne/cm2, x) are y=760.12-36.06x, gamma=-0.978 (for 5 h); y=781.87-36.66x, gamma=-0.980 (for 6 h). This in vitro study demonstrates that the production of IL-8 can be regulated by fluid shear stress, and the production of IL-8 induced by shear stress is not only time-dependent but also force intensity-dependent. These observations suggest that the low fluid shear stress induces much more IL-8 secretion, which may play an important role in the pathogenesis and development of both inflammation and atherosclerosis.
Cells, Cultured ; Endothelial Cells ; cytology ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Humans ; Interleukin-8 ; biosynthesis ; genetics ; Pulsatile Flow ; RNA, Messenger ; biosynthesis ; genetics ; Stress, Mechanical ; Umbilical Veins ; cytology

Interleukin-8 is CXC chemokine that is initially discovered using chemotaxis and the activation of neutrophils and induces the migration and proliferation of smooth muscle cells. Interleukin-8 is a potent angiogenic factor that may play a role in atherosclerosis. To establish the temporal correlation between IL-8 expression and plaque development, we examined the expression during atherosclerosis of hyperlipemia rabbits using immunohistochemistry, ELISA, in situ hybridization. By location of immunohistochemistry, the expression of IL-8 protein increased obviously in intima of hyperlipemia rabbits at 8 and 12 week. Quantitative analysis of the expression of IL-8 Immunohistochemistry indicated that positive area of AS model was 4.48 times and 8.76 times that of control group at 8 and 12 week. The valuation of IOD of AS model was 4.16 times and 4.36 times that of control group at 8 and 12 week. By specific ELISA, the ratio of the IL-8 protein to total protein of AS model was 1.84 times and 2.06 times that of control group at 8 and 12 week. By location of in situ hybridization, positive location was strong in intima of hyperlipemia rabbits at 8 week. We observed the dynamic alteration of interleukin-8 protein and gene expression in atherosclerotic lesions of hyperlipemia rabbits with establishing model. Interleukin-8 protein and gene expression was up-regulation in the development of fatty streaks in hyperlipemia rabbit.
Animals ; Aorta ; metabolism ; Atherosclerosis ; etiology ; metabolism ; Hyperlipidemias ; complications ; Interleukin-8 ; biosynthesis ; genetics ; Male ; RNA, Messenger ; biosynthesis ; genetics ; Rabbits

Fluid shear stress plays an important role in many physiological and pathophysiological processes of the cardiovascular system. It modulates vascular function and structure via stimulating mechanosensitive endothelial cell signal events. Previous studies have identified that the exposure of vascular endothelial cells to fluid mechanical forces can modulate the expressions of many genes, including IL-8 gene. In order to gain an insight into the role of extracellular signal regulated kinase (ERK1/2) signal pathway in the expression of IL-8 mRNA in human umbilical vein endothelial cells (HUVECs) under the stimulation by low shear stress (4.20 dyne/cm2), we employed Western blot to measure phosphorylation of ERK1/2 and used quantitative reversal transcription-polymerase chain reaction (qRT-PCR) to assay the expression of IL-8 mRNA. The results showed: (1) Shear stress could activate ERK1/2 with a rapid, biphasic time course (maximum by 10 min and basal by 2 h); the treatment of HUVECs with Genistein (a highly specific inhibitor of tyrosine protein kinase, TPK) or PD98059 (the inhibitor of mitogen-activated protein/extracellular signal regulated kinase kinase, MEK) culd prevent shear-dependent activation of ERK1/2; (2) When treated with Genistein or PD98059, significant inhibition of IL-8 mRNA expression induced by low shear stress was observed in HUVECs. This in vitro study demonstrates that ERK1/2 plays an important role in IL-8 mRNA expression induced by low shear stress.
Cells, Cultured ; Endothelium, Vascular ; cytology ; metabolism ; Humans ; Interleukin-8 ; biosynthesis ; genetics ; Mitogen-Activated Protein Kinase 1 ; physiology ; Mitogen-Activated Protein Kinase 3 ; physiology ; RNA, Messenger ; biosynthesis ; genetics ; Signal Transduction ; Stress, Mechanical ; Umbilical Veins ; cytology