BACKGROUND Acute lung injury(ALI)is a common and life-threatening complication of severe acute pancreatitis(SAP).There are currently limited effective treatment options for SAP and associated ALI.Calycosin(Cal),a bioa...BACKGROUND Acute lung injury(ALI)is a common and life-threatening complication of severe acute pancreatitis(SAP).There are currently limited effective treatment options for SAP and associated ALI.Calycosin(Cal),a bioactive constituent extracted from the medicinal herb Radix Astragali exhibits potent anti-inflammatory properties,but its effect on SAP and associated ALI has yet to be determined.AIM To identify the roles of Cal in SAP-ALI and the underlying mechanism.METHODS SAP was induced via two intraperitoneal injections of L-arg(4 g/kg)and Cal(25 or 50 mg/kg)were injected 1 h prior to the first L-arg challenge.Mice were sacrificed 72 h after the induction of SAP and associated ALI was examined histologically and biochemically.An in vitro model of lipopolysaccharide(LPS)-induced ALI was established using A549 cells.Immunofluorescence analysis and western blot were evaluated in cells.Molecular docking analyses were conducted to examine the interaction of Cal with HMGB1.RESULTS Cal treatment substantially reduced the serum amylase levels and alleviated histopathological injury associated with SAP and ALI.Neutrophil infiltration and lung tissue levels of neutrophil mediator myeloperoxidase were reduced in line with protective effects of Cal against ALI in SAP.Cal treatment also attenuated the serum levels and mRNA expression of pro-inflammatory cytokines tumor necrosis factor-α,interleukin-6,IL-1β,HMGB1 and chemokine(CXC motif)ligand 1 in lung tissue.Immunofluorescence and western blot analyses showed that Cal treatment markedly suppressed the expression of HMGB1 and phosphorylated nuclear factor-kappa B(NF-κB)p65 in lung tissues and an in vitro model of LPSinduced ALI in A549 cells suggesting a role for HGMB1 in the pathogenesis of ALI.Furthermore,molecular docking analysis provided evidence for the direct interaction of Cal with HGMB1.CONCLUSION Cal protects mice against L-arg-induced SAP and associated ALI by attenuating local and systemic neutrophil infiltration and inflammatory response via inhibition of HGMB1 and the NF-κB signaling pathway.展开更多
Objective： The mechanisms by which lipopolysaccharide （LPS） pretreatment induces cardioprotection following ischaemia/reperfusion （I/R） have not been fully elucidated. We hypothesized that activation of phosphoin...Objective： The mechanisms by which lipopolysaccharide （LPS） pretreatment induces cardioprotection following ischaemia/reperfusion （I/R） have not been fully elucidated. We hypothesized that activation of phosphoinositide 3-kinase （PI3K）/Akt and high mobility group box 1 （HMGBxl） signaling plays an important role in LPS-induced cardioprotection. Methods： In in vivo experiments, age- and weight- matched male C57BL/10Sc wild type mice were pretreated with LPS before ligation of the left anterior descending coronary followed by reperfusion. Infarction size was examined by triphenyltetrazolium chloride （TTC） staining. Akt, phospho-Akt, and HMGBxl were assessed by immunoblotting with appropriate primary antibodies. In situ cardiac myocyte apop- tosis was examined by the TdT-mediated dUTP nick-end labeling （TUNEL） assay. In an in vitro study, rat cardiac myoblasts （H9c2） were subdivided into two groups, and only one was pretreated with LPS. After pretreatment, the cells were transferred into a hypoxic chamber under 0.5% 02. Levels of HMGBxl were assessed by immunoblot. Results： In the in vivo experiment, pretreatment with LPS reduced the at risk infarct size by 70.6% and the left ventricle infarct size by 64.93% respectively. Pretreatment with LPS also reduced cardiac myocytes apoptosis by 39.1% after ischemia and reperfusion. The mechanisms of LPS induced cardioprotection involved increasing PI3K/Akt activity and decreasing expression of HMGBxl. In the in vitro study, pretreatment with LPS reduced the level of HMGBxl in H9c2 cell cytoplasm following hypoxia. Conclusion： The results suggest that the cardioprotection following I/R induced by LPS pretreatment involves PI3K/Akt and HMGBxl pathways.展开更多
文摘BACKGROUND Acute lung injury(ALI)is a common and life-threatening complication of severe acute pancreatitis(SAP).There are currently limited effective treatment options for SAP and associated ALI.Calycosin(Cal),a bioactive constituent extracted from the medicinal herb Radix Astragali exhibits potent anti-inflammatory properties,but its effect on SAP and associated ALI has yet to be determined.AIM To identify the roles of Cal in SAP-ALI and the underlying mechanism.METHODS SAP was induced via two intraperitoneal injections of L-arg(4 g/kg)and Cal(25 or 50 mg/kg)were injected 1 h prior to the first L-arg challenge.Mice were sacrificed 72 h after the induction of SAP and associated ALI was examined histologically and biochemically.An in vitro model of lipopolysaccharide(LPS)-induced ALI was established using A549 cells.Immunofluorescence analysis and western blot were evaluated in cells.Molecular docking analyses were conducted to examine the interaction of Cal with HMGB1.RESULTS Cal treatment substantially reduced the serum amylase levels and alleviated histopathological injury associated with SAP and ALI.Neutrophil infiltration and lung tissue levels of neutrophil mediator myeloperoxidase were reduced in line with protective effects of Cal against ALI in SAP.Cal treatment also attenuated the serum levels and mRNA expression of pro-inflammatory cytokines tumor necrosis factor-α,interleukin-6,IL-1β,HMGB1 and chemokine(CXC motif)ligand 1 in lung tissue.Immunofluorescence and western blot analyses showed that Cal treatment markedly suppressed the expression of HMGB1 and phosphorylated nuclear factor-kappa B(NF-κB)p65 in lung tissues and an in vitro model of LPSinduced ALI in A549 cells suggesting a role for HGMB1 in the pathogenesis of ALI.Furthermore,molecular docking analysis provided evidence for the direct interaction of Cal with HGMB1.CONCLUSION Cal protects mice against L-arg-induced SAP and associated ALI by attenuating local and systemic neutrophil infiltration and inflammatory response via inhibition of HGMB1 and the NF-κB signaling pathway.
文摘Objective： The mechanisms by which lipopolysaccharide （LPS） pretreatment induces cardioprotection following ischaemia/reperfusion （I/R） have not been fully elucidated. We hypothesized that activation of phosphoinositide 3-kinase （PI3K）/Akt and high mobility group box 1 （HMGBxl） signaling plays an important role in LPS-induced cardioprotection. Methods： In in vivo experiments, age- and weight- matched male C57BL/10Sc wild type mice were pretreated with LPS before ligation of the left anterior descending coronary followed by reperfusion. Infarction size was examined by triphenyltetrazolium chloride （TTC） staining. Akt, phospho-Akt, and HMGBxl were assessed by immunoblotting with appropriate primary antibodies. In situ cardiac myocyte apop- tosis was examined by the TdT-mediated dUTP nick-end labeling （TUNEL） assay. In an in vitro study, rat cardiac myoblasts （H9c2） were subdivided into two groups, and only one was pretreated with LPS. After pretreatment, the cells were transferred into a hypoxic chamber under 0.5% 02. Levels of HMGBxl were assessed by immunoblot. Results： In the in vivo experiment, pretreatment with LPS reduced the at risk infarct size by 70.6% and the left ventricle infarct size by 64.93% respectively. Pretreatment with LPS also reduced cardiac myocytes apoptosis by 39.1% after ischemia and reperfusion. The mechanisms of LPS induced cardioprotection involved increasing PI3K/Akt activity and decreasing expression of HMGBxl. In the in vitro study, pretreatment with LPS reduced the level of HMGBxl in H9c2 cell cytoplasm following hypoxia. Conclusion： The results suggest that the cardioprotection following I/R induced by LPS pretreatment involves PI3K/Akt and HMGBxl pathways.
