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Objective:To observe the therapeutic effect of quercetin (QUE) on triggering receptor expressed on myeloid cells (TREM-1) activated macrophage inflammation and lipopolysaccharide (LPS) induced acute lung injury (ALI) in mice, and explore its possible mechanism.Methods:In vitro cell experiment: The primary peritoneal macrophages of mice were collected by intraperitoneal injection of 3% calcium mercaptan acetate. The collected cells were divided into blank control group, dimethylsulfoxide (DMSO) vehicle group, TREM-1 agonist group (10 μg/ml), QUE group (10 μmol/L) and TREM-1 agonist + QUE group (cells were pretreated with 10 μmol/L QUE for 30 min before adding agonist). Enzyme linked immunosorbent assay (ELISA) was used to detect the secretion of interleukin (IL)-1β, tumor necrosis factor (TNF)-α and IL-6 in the culture supernatant of primary macrophages; To observe the effect of QUE on LPS-induced TREM-1 protein levels, macrophages were divided into: normal control group, LPS group (100 ng/ml) and LPS+ QUE treatment group [macrophages were pretreated with 10 μmol/L QUE for 2 hours, and then incubated with LPS (100 ng/ml) for 16 hours]. Western blot was used to detect the expression of TREM-1 protein. In animal experiments: 80 male C57BL/6 mice were randomly divided into 4 groups (20 in each group): normal control group, ALI model group, QUE group and QUE treatment group (LPS+ QUE). In the ALI model group, the ALI model was established by intratracheal injection of 5 mg/kg LPS; The mouse ALI model was established by intratracheal injection of LPS 5 mg/kg in the QUE treatment group, and then intraperitoneal injection of 15 mg/kg QUE. The control group was given the same amount of normal saline intratracheal followed by intraperitoneal injection of DMSO, and the QUE group was given the same amount of normal saline intratracheal followed by intraperitoneal injection of 15 mg/kg QUE. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of lung tissue in each group; Inflammatory cells including IL-1β, TNF- α and IL-6 in bronchoalveolar lavage fluid (BLAF) of mice in each group were counted ; The expression of TREM-1 mRNA and protein in lung tissue of mice in each group was detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) and Western blot. Results:In vitro cell experiment: the secretion of IL-1β, TNF-α and IL-6 in the supernatant of primary macrophages in TREM-1 agonist group was higher than those in DMSO vehicle group, while the secretion of IL-1β, TNF-αand IL-6 in the supernatant of primary macrophages in TREM-1 agonist + QUE group were lower than that of TREM-1 agonist group (all P<0.001). The expression of TREM-1 protein in LPS group was higher than that in control group ( P<0.05), while the expression of TREM-1 protein in LPS + QUE group was lower than that in LPS group ( P<0.05). Animal experiments showed that compared with the control group, the ALI model group had higher lung pathological injury score, more total cells, macrophages and neutrophils in BALF and increased TNF-α, IL-6, IL-1β content (all P<0.001). The above indexes in QUE group were lower than those in ALI model group (all P<0.001). The results of qRT-PCR and Western blot showed that compared with the control group, the expression of TREM-1 mRNA and protein in the lung tissue of ALI model group was increased, while the expression of TREM-1 mRNA and protein in the lung tissue of QUE group was lower than that of ALI model group (all P<0.05). Conclusions:Quercetin can inhibit TREM-1 activation, reduce macrophage inflammatory response and LPS induced acute lung injury in mice.
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Objective To evaluate the effect of sevoflurane postconditioning on microRNA-133a (miR-133a) expression during myocardial ischemia-reperfusion (I/R) in mice.Methods Thirty adult male C57 mice,weighing 20-30 g,were randomized to 3 groups (n =10 each) using a random number table:control group (group C),I/R group,and sevoflurane postconditioning group (group SP).In I/R and SP groups,hearts from adult male C57 mice were exposed and subjected to 30 min of ischemia and 180 min of reperfusion in anesthetized mice according to the method described by Das et al.In group C,only thoracotomy was performed without ligation of the coronary artery.In group SP,2.4％ sevoflurane was inhaled for 5 min starting from the onset of reperfusion to perform sevoflurane postconditioning.At 180 min of reperfusion,blood samples from the femoral vein were collected for determination of serum lactic dehydrogenase (LDH) and creatine kinase (CK) activities using the colorimetric method.The mice were then sacrificed,and myocardial specimens were obtained for determination of myocardial infarct size,miR133a and caspase-9 mRNA expression (by real-time reverse transcriptase polymerase chain reaction),and caspase-9 expression (by Western blot).Results Compared with group C,the serum LDH and CK activities and myocardial infarct size were significantly increased in I/R and SP groups,the expression of miR-133a was significantly down-regulated,and the expression of caspase-9 protein and mRNA was significantly up-regulated in group I/R,and the expression of miR-133a and caspase-9 protein and mRNA was significantly up-regulated in group SP (P＜0.05).Compared with group I/R,the serum LDH and.CK activities and myocardial infarct size were significantly decreased,the expression of miR-133a was significantly up-regulated,and the expression of caspase-9 protein and mRNA was significantly downregulated in group SP (P＜0.05).Conclusion The mechanism by which sevoflurane postconditioning inhibits cell apoptosis during myocardial I/R is related to up-regulation of miR-133a expression in mice.
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Objective The aim of this study is to investigate the correlation between small airway disease and airway hyper-responsiveness,and explore the predicting value of small airway diseases for asthma.Methods Pulmonary function tests and bronchial provocation tests were performed in 249 patients with chronic cough from Sep. 2004 to Sep. 2006.The incidence of small airway disease and airway hyper-responsiveness were observed.Results There were 91 patients with small airway disease,and 103 patients with positive tests for bronchial provocation in total 249 chronic cough patients.The incidence of positive tests for bronchial provocation in 91 patients(73.63%)with small airway disease was significantly higher than that in 158 patients(22.78%)without it,P