ABSTRACT
AIM:To explore the role of sphingosine 1-phosphate (S1P) in the dysfunction of vascular endo-thelial cells exposed to high glucose.METHODS: In human aortic endothelial cells cultured under high-glucose ( 22 mmol/L glucose) medium, nitric oxide ( NO) level, polymorphonuclear neutrophil-endothelial cell adhesion rate, protein level of intercellular adhesion molecule-1 ( ICAM-1) , migration of endothelial cells and Akt/endothelial nitric oxide syn-thase ( eNOS) pathway activation were observed after S1P, sphingosine kinase-1 inhibitor and/or Akt inhibitor treatments. RESULTS:S1P decreased NO level, increased polymorphonuclear neutrophil adhesive rate, enhanced ICAM-1 protein level, and inhibited migration of endothelial cells and activation of Akt/eNOS pathway in endothelial cells cultured under high-glucose condition.Sphingosine kinase-1 inhibitor, which reduced S1P content, significantly improved the above endo-thelial cell function indexes and restored the activation of Akt/eNOS pathway.CONCLUSION: S1P promoted high glu-cose-induced dysfunction of endothelial cells probably by inhibiting the activation of Akt/eNOS signal pathway.Targeting S1P is expected to become one of potential treatment strategies to reduce endothelial cell dysfunction.
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In order to establish an efficient and low-cost production procedure of recombinant glycerol kinase (r-GK), we expressed the r-GK gene at high level in E. coli by induction with lactose on a large-scale fermentation of 300L. The results showed that the biomass concentration reached OD600 of 42 and the expression of r-GK in E. coli accounted for about 30% of total soluble protein. The cell-free extract was processed by selective thermo-denaturation and then purified with Ni sepharose FF column chromatography. Finally, highly purified r-GK was obtained and its purity reached 97% by using analysis on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), polyacrylamide gel electrophoresis (PAGE) and gradient polyacrylamide gel electrophoresis (Gradient PAGE). Further identification study showed that the molecular weight of r-GK was 120kDa with two subunit of 58kDa. Contaminants of NADH oxidase and catalase were not detected in the sample pool of r-GK. The purified r-GK was able to retain about 85% of its initial activity at 4 degrees C for 30 days. After lyophilized, it can retain 93% of its initial activity at 4 degrees C for one year.
Subject(s)
Escherichia coli , Genetics , Metabolism , Fermentation , Glycerol Kinase , Genetics , Recombinant Proteins , GeneticsABSTRACT
OBJECTIVE:To study the effect of different dosage of grassleaf sweetflag rhizome on central nervous system.METHODS:The effects of different dosage of grassleaf sweetflag rhizome on the hours of sleep and hypoxia live time of mice were observed,and the effects of which on water contents of brain tissues,apoptosis,endothelin(ET),malonaldehyde(MDA),erythrocuprein(SOD),glutathione peroxidase(GSH-Px),etc.in rats with cerebral ischemia were observed as well.RESULTS:Compared with the control group,different dosage of grassleaf sweetflag rhizome could shorten the sleeping time of mice and prolong the live time of hypoxia mice;high dosage of grassleaf sweetflag rhizome could remarkably decrease the water content of brain tissue and MDA level and inhibit the apoptosis of brain tissue cells while increase the activity of SOD and GSH-Px.CONCLUSION:High dosage of grassleaf sweetflag rhizome has the strongest protective effects to central nervous system,the effects of middle and low dosage of grassleaf sweetflag rhizome are lower than that of the high dosage.
ABSTRACT
Objective: To determine the contents of ?-Asarone and ?-Asarone in Xing Nao nasal drops. Methods: HPLC was used with ODS C18 column (150mm?4.6mm, 5?m). Methanol mixture : water being 6 : 4 and Patassium biphoepate 1.4 and Dodecyl Sulphonic acid sodium salt 1.2g in 1000mL mixture served as mobile phase, detection wavelength at 257nm and flow rate being 1.0mL/min. Results: The mean recovery was 99.38 %(RSD=2.25 %) for ?-Asarone and 96.59 %(RSD=2.16) for ?-Asarone. Conclusion: this method is simple,rapid and accurate.