Purpose： To investigate the effects of salvianolic acid B （SAB） on tumor necrosis factor a （TNF-a） induced alterations of cerebral microcirculation with a bone-abrading model. Methods： The influences of cranioto...Purpose： To investigate the effects of salvianolic acid B （SAB） on tumor necrosis factor a （TNF-a） induced alterations of cerebral microcirculation with a bone-abrading model. Methods： The influences of craniotomy model and bone-abrading model on cerebral microcirculation were compared. The bone-abrading method was used to detect the effects of intracerebroventricular application of 40 μg/kg.bw TNF-a on cerebral venular leakage of fluorescein isothiocyanate （FITC）- albulmin and the rolling and adhesion of leukocytes on venules with fluorescence tracer rhodamine 6G, The therapeutical effects of SAB on TNF-a induced microcirculatory alteration were observed, with continuous intravenous injection of 5 mg/kg.h SAB starting at 20 min before or 20 min after TNF-a administration, respectively, The expressions of CDllb/CD18 and CD62L in leukocytes were measured with flow cytometry, Immunohistochemical staining was also used to detect E-selectin and ICAM-1 expression in endothelial cells, Results： Compared with craniotomy method, the bone-abrading method preserved a higher erythrocyte velocity in cerebral venules and more opening capillaries. TNF-a intervention only caused responses of vascular hyperpermeability and leukocyte roiling on venular walls, without leukocyte adhesion and other hemodynamic changes. Pre- or post-SAB treatment attenuated those responses and suppressed the enhanced expressions of CDII b/CDI8 and CD62L in leukocytes and E-selectin and ICAM-I in endothelial cells induced by TNF-a. Conclusions： The pre- and post-applications of SAB during TNF-a stimulation could suppress adhesive molecular expression and subsequently attenuate the increase of cerebral vascular permeability and leukocyte rolling.展开更多
The interaction between BSA and epicatechin was studied using fluorescence quenching titrations combined with trilinear decomposition method and excitation-emission matrix(EEM)fluorescence.The resolved spectra were hi...The interaction between BSA and epicatechin was studied using fluorescence quenching titrations combined with trilinear decomposition method and excitation-emission matrix(EEM)fluorescence.The resolved spectra were highly similar with the actual ones which indicated that the resolved results were reliable.The relevant parameters of the binding process were obtained by quantifying each substance in the complicated mixtures in situ.The quenching was static quenching,epicatechin had a weak interaction with BSA and the binding site was one.The total concentration and the free concentration of quenchers had different effect on the system.The results demonstrated that the method exploited in this article is a useful tool to investigate complicated interactions,avoiding complicated pretreatment and simplify experimental procedure.展开更多
基金This study was supported by the General Program from the Natural Science Foundation of China，Southern Medical University Research Program for Young Scientists Training
文摘Purpose： To investigate the effects of salvianolic acid B （SAB） on tumor necrosis factor a （TNF-a） induced alterations of cerebral microcirculation with a bone-abrading model. Methods： The influences of craniotomy model and bone-abrading model on cerebral microcirculation were compared. The bone-abrading method was used to detect the effects of intracerebroventricular application of 40 μg/kg.bw TNF-a on cerebral venular leakage of fluorescein isothiocyanate （FITC）- albulmin and the rolling and adhesion of leukocytes on venules with fluorescence tracer rhodamine 6G, The therapeutical effects of SAB on TNF-a induced microcirculatory alteration were observed, with continuous intravenous injection of 5 mg/kg.h SAB starting at 20 min before or 20 min after TNF-a administration, respectively, The expressions of CDllb/CD18 and CD62L in leukocytes were measured with flow cytometry, Immunohistochemical staining was also used to detect E-selectin and ICAM-1 expression in endothelial cells, Results： Compared with craniotomy method, the bone-abrading method preserved a higher erythrocyte velocity in cerebral venules and more opening capillaries. TNF-a intervention only caused responses of vascular hyperpermeability and leukocyte roiling on venular walls, without leukocyte adhesion and other hemodynamic changes. Pre- or post-SAB treatment attenuated those responses and suppressed the enhanced expressions of CDII b/CDI8 and CD62L in leukocytes and E-selectin and ICAM-I in endothelial cells induced by TNF-a. Conclusions： The pre- and post-applications of SAB during TNF-a stimulation could suppress adhesive molecular expression and subsequently attenuate the increase of cerebral vascular permeability and leukocyte rolling.
基金financially supported by the National Natural Science Foundation of China(21175041)the National Basic Research Program of China(2012CB910602)
文摘The interaction between BSA and epicatechin was studied using fluorescence quenching titrations combined with trilinear decomposition method and excitation-emission matrix(EEM)fluorescence.The resolved spectra were highly similar with the actual ones which indicated that the resolved results were reliable.The relevant parameters of the binding process were obtained by quantifying each substance in the complicated mixtures in situ.The quenching was static quenching,epicatechin had a weak interaction with BSA and the binding site was one.The total concentration and the free concentration of quenchers had different effect on the system.The results demonstrated that the method exploited in this article is a useful tool to investigate complicated interactions,avoiding complicated pretreatment and simplify experimental procedure.
