Role and mechanism of FIRRE in LPS-induced acute lung injury
Objective To explore the role and mechanism of FIRRE in lipopolysaccharide(LPS)induced acute lung injury(ALI).Methods The study was conducted at Binzhou Medical University Hospital from June 2020 to May 2022.Part Ⅰ:The role of FIRRE in LPS-induced A549 cell injury.A549 cells were divided into a control group,a low molecular weight heparin calcium(LMWH)group,a LPS group,and a LPS+LMWH group,which were treat by normal saline,5 IU/ml LMWH,10 mg/L LPS,and 10 mg/L LPS+5 IU/ml LMWH for 24 h.The cell activity of each group was detected by CCK-8,the expressions of interleukin(IL)-6,IL-10,and tumor necrosis factor(TNF)-α were detected by enzyme-linked immunosorbent assay(ELISA),and the relative expression of FIRRE gene was detected by real-time quantitative PCR.Part Ⅱ:The role of FIRRE in LPS-induced ALI in C57BL/6J mice.Twenty-four healthy and clean SPF grade male C57BL/6J mice(body weight 25-30 g,6-8 weeks old)were randomly divided into 3 groups.The control group was injected with equal volume of normal saline,the ALI group was injected with 5 mg/kg LPS to induce ALI,and the LMWH group was intraperitoneally injected with 5 mg/kg LPS+5 AXa IU/kg LMWH.The changes of hair color,reaction ability,and resistance to external environment were evaluated at 6 h and 12 h after LPS injection.HE staining was used to observe the degree of lung tissue injury,and the lung injury score was calculated.Blood samples were collected from the abdominal main vein,and the expressions of IL-6 and IL-10 in serum were detected by ELISA.The levels of IL-6 and IL-10 in bronchoalveolar lavage fluid(BALF)were detected by ELISA.The relative expression of FIRRE gene was detected by RT-PCR.One-way analysis of variance,LSD-t test,and Dunnett-t test were used.Results Part Ⅰ:The activity of A549 cells in the LPS group was lower than that in the control group,and the activity of A549 cells in the LPS+LMWH group was higher than that in the LPS group,with a statistically significant difference among multiple groups(F=44.25,P＜0.05).The levels of IL-6,IL-10,and TNF-α in the LPS group and LPS+LMWH group were higher than those in the control group and LMWH group,and the levels of IL-6,IL-10,and TNF-α in the LPS+LMWH group were lower than those in the LPS group(all P＜0.05).The expression levels of FIRRE in A549 cells of the LPS group and LPS+LMWH group were higher than that of the control group,and that of the LPS+LMWH group was lower than that of the LPS group,with a statistically significant difference among multiple groups(F=242.23,P＜0.001).Part Ⅱ:The reaction ability and resistance to external environment of the mice in the ALI group and LMWH group were lower than those in the control group.At 6 h and 12 h after LPS injection,in the ALI group,HE staining of lung tissue sections showed a large number of inflammatory cell infiltration in the alveolar cavity,alveolar collapse,The lung injury score was 4.The inflammatory injury of lung tissue sections showed by HE staining in the LMWH group was lower than that in the ALI group.The levels of IL-6 and IL-10 in serum and BALF in the ALI group were higher than those in the control group(all P＜0.05),and the levels of IL-6 and IL-10 in serum and BALF in the LMWH group were lower than those in the ALI group(all P＜0.05).The FIRRE expressions in the ALI group and LMWH group were higher than that in the control group,and the expression in the LMWH group was lower than that in the ALI group,with statistically significant differences among multiple groups(F=7.23 and 6.51,both P＜0.05).Conclusions Part Ⅰ:LMWH may reduce LPS-induced injury of A549 cells by inhibiting the expression of FIRRE gene and down-regulating the levels of inflammatory factors.Part Ⅱ:LMWH may reduce LPS-induced ALI in C57BL/6J mice by inhibiting the expression of FIRRE gene and down-regulating the levels of inflammatory factors.
万方数据
维普
