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Objective:To explore the changes of blood viscosity in high-intensity alternating magnetic field and the mechanisms.Methods:Five adult sheep were randomly selected and the blood samples were placed in highintensity alternating magnetic field.Before and after exposure,the blood samples were taken and divided into 2 groups:a control group and a magnetic field group.The blood rheology and transmission electron microscopy (TEM) were performed.Results:Compared to the control group,the high shear viscosity of whole blood was decreased in the magnetic field group (P＜0.05);the whole blood low shear viscosity and plasma viscosity were also decreased (both P＜0.01).TEM showed the changes in red blood cell morphology and the double concave disc curvature.The radian of double concave disc and cell volume in the magnetic field group was larger than those in the control group.Conclusion:The high intensity alternating magnetic field may affect the distribution of surface charge and molecular current in blood cells,which in turn decrease the aggregation of cells and the blood viscosity.
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Th17 cells were identified as an independent lineage of CD4+ T cells that secrete a distinctive set of immunoregulatory cytokines, which play an important role in the pathogenesis of a diverse group of immune-mediated diseases. Recent data in humans and mice trials suggest that as the hallmark cytokine of Th17 cells, IL-17 involved in the inducement and the inflammation of allergy, such as asthma. IL-17 induces chemokine IL-8, and prominently recruits neutrophils in the airways in severe asthma exacerbations and may contribute to airway gland hypersecretion, bronchial hyper-reactivity and airway wall remodelling in asthma. Given the strong association between excessive Th17 activity and human diseases, new therapeutic approaches targeting Th17 cells are highly promising, but the potential clinical application need further investigation.
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BACKGROUND: It is reported that ceramide signal pathway may play an important role in the apoptosis of vascular endothelial cell and then lead to the progress of atherosclerosis, such as the formation of foam cells and the proliferation of smooth muscular cells.OBJECTIVE: To study the changes of the sphingomylinase activity and ceramide content in aorta of rabbits with experimental atherosclerosis and investigate the regulative effects and mechanism of emodin on them as compared with positive fenofibrate.DESIGN: Completely randomized controlled design.SETTING: Laboratory of Pharmacology & Toxicology, School of Pharmaceutical Science of Sun Yat-sen University.MATERIALS: The experiment was completed at the Laboratory of Pharmacology & Toxicology, School of Pharmaceutical Science of Sun Yat-sen University from July to December 2003. Totally 48 New Zealand male rabbits were selected. Forty animal models of atherosclerosis were made with high cholesterol feed, and the other 8 rabbits were selected as the normal controls. Model animals were divided randomly into model group, 5 mg/kg emodin group, 10 mg/kg emodin group, 20 mg/kg emodin group and 25mg/kg fenofibrate group with 8 in each group.METHODS: At the seventh weeks of model duplication, 5 mg/kg, 10 mg/kg and 20 mg/kg emodin were perfused in rabbits of emodin groups respectively, and 25 mg/kg fenofibrate was perfused in rabbits of fenofibrate group. Emodin and fenofibrate were diluted or suspensed with 2 mL saline once per day respectively. Rabbits in normal control group and model group were administrated with the same volume of saline for 4 weeks. The rabbits were raised separately and were fed with 135-150 g food per day.MAIN OUTCOME MEASURES: [1] The area of the lipid plaque in aortal intima; [2] the content of serum TC and TG; [3] SOD activity and MDA content; [4] SMase activity and CER content in aorta.RESULTS: Totally 48 rabbits entered the final analysis. [1] Area of the lipid plaque: Area of the lipid plaque was (48.87±15.5) % in the model group, which was larger than that in each emodin group (P ＜ 0.05 or 0.01),especially larger than that in the 10 mg/kg emodin group (22.19±12.9)%while that in the fenofibrate group was similar to that in the model group (P ＞ 0.05). [2] Content of serum TC and TG: The anrtal intima of control was smooth. Content of serum TC and TG in each emodin group were similar to those in the model group (P ＞ 0.05), but those in the 25 mg/kg fenofibrate group were lower than those in the model group (P ＜ 0.05). [3]Content of SOD and MDA in plasma: SOD activity of rabbits in each emodin group was higher than that in the model group (P ＜ 0.05, P ＜ 0.01),but the MDA activity in the 10 mg/kg and 20 mg/kg emodin group was lower than that in the model group (P ＜ 0.05). The MDA activity in the25 mg/kg fenofibrate group was similar to that in the model group (P ＞ 0.05).[4] Content of SMase and CER: Those in the model group were higher than those in the normal control group, but those in the 5, 10 and 20 mg/kg emodin groups were lower than those in the model group; those in the 25 mg/kgfenofibrate group were similar to those in the model group (P ＞ 0.05). [5]Analysis of correlation: Content of SMase was in positive relation with blood cholesterol (r=0.542, P ＜ 0.01), in positive relation with blood MDA (r=0.789, P ＞ 0.01), and in negative relation with blood SOD(r=-0.936, P ＞ 0.01); content of CER was in positive relation with blood cholesterol (r=0.433, P ＞ 0.05), in positive relation with blood MDA (r=0.673, P ＞ 0.01), and in negative relation with blood SOD (r=-0.876, P ＞ 0.01).CONCLUSION: The study finds that emodin, despite its insignificant effects on decreasing TG or TC, can protect vascular endothelial cells and reduce the area of lipid-laden plague of aortal intima by antioxidation, inhibition of the sphingomyelinase activity and reduction of the content of ceramide. It is suggested that moderate dosage of emodin employed in the study may be most appropriate to atherosclerosis treatment.
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Aim To find out the relationship between muscarinic receptor and reactive oxygen species (ROS) and the probable differences between the four muscarinic receptor subtypes. Methods We transfected the plasmid encoding muscarinic receptor (including subtypes: M_1, M_2, M_3 and M_4) into PC12 cells. Then PC12 cells were exposed to hydrogen peroxide (H_2O_2), carbachol and other inhibitors such as atropine, LY294002 and PD98059. Results The results showed that activation of muscarinic receptor by carbachol protected PC12-M_1, PC12-M_2,PC12-M_3 and PC12-M_4 cells from apoptosis induced by H_2O_2. There was no statistical difference in the protective effect between these four muscarinic receptor subtypes. By using the inhibitors, we found that atropine and LY294002 blocked the protective effect of activation of muscarinic receptor on apoptosis induced by H_2O_2. Conclusion Activation of muscarinic receptor retarded the apoptosis induced by H_2O_2. There was no difference between the four muscarinic receptor subtypes. The protective effect was mainly mediated by the activation of muscarinic receptor and phosphatidylinositol-3 kinase (PI3K).
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AIM: To Screen and identify differentially expressed genes that involved in apoptosis model in rat cerebellar granule neurons (CGNs).METHODS: The rat cerebellar granule neurons were isolated and primarily cultured. Fluorescent differential display RT-PCR (FDD RT-PCR) was performed to screen differentially expressed ESTs in the apoptosis model of primarily cultured rat CGNs. ESTs were subcloned into pGEM-T EasyTM vector and then sequenced. Alignment assay in non-redunant database was applied for encoding information. Reverse Northern blotting was used to appraise the results from DDRT-PCR.RESULTS: 164 pieces of differentially expressed ESTs were obtained by FDDRT-PCR. 17 of them were subcloned and sequenced. 5 ESTs of 17 were confirmed to be positive results by reverse Northern blotting. CONCLUSION: DD-PCR is a rapid, simple-operation and sensitive method for screening differentially expressed genes, which would contribute to the molecular mechanisms of apoptosis/survive of CGNs.
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AIM: To study the changes of the sphingomylinase activity and ceramide content in rabbit aorta of experimental atherosclerosis and investigate the effects of emodin on them. METHODS: The qualified rabbits were fed with food containing 1% cholesterol and 5% lard for 10 weeks to establish the animal models. The concentration of cholesterol (TC) was assayed by a enzyme method. Trace-fast-test method was used to test the activity of superoxide dismutase (SOD) and motified-BAMuGuoFu methods was employed to assay the content of myocardial malondialdehyde (MDA). Radiolabeled-enzyme-tracing was used to detect the activity of the sphingomyelinase,and thin-layered scanning was conducted to analyze the content of the ceramide in aorta. RESULTS: The ceramide content in aorta and the sphingomyelinase activity were markedly increased in the rabbits with experimental atherosclerosis. The increase was positively correlated with the content of TC and MDA and negatively correlated with the activity of SOD in blood. Compared to the model animals, emodin at concentration of 5 mg?kg -1 , 10 mg?kg -1 and 20 mg?kg -1 respectively reduced the area of plague on endothelium in rabbit's aortic artery and elevated the activity of SOD (P
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AIM: To clone the full-length of 75A EST. METHODS: After the extraction of total RNA from primary cultured rat cerebellar granule cell of 7DIV in the medium containing 25 mmol/L KCl, T_4 DNA ligase-mediated 5' RACE was used to retrieve 5' unknown sequence of 75A EST, and the first round 5' RACE PCR product was subcloned into pGEM-T easy vector for sequence and homogeneous analysis. RESULTS: The first round of 5' RACE produce a 2.5 kb band, and 75A EST was identified to be partial sequence of Neuron-derived orphan receptor (Nor1) gene. After two more rounds RACE, we firstly cloned the full-length of Nor-1 cDNA. CONCLUSION: T_4 DNA ligase mediated 5' RACE is an efficient method to retrieve information about the 5' termini of mRNAs, and lay a foundation for further study which role Nor1 play in the cerebellar granule cell differentiation or survive.