Experimental Study of Reducing Sepsis-induced Acute Lung Injury by Inhibiting Ferroptosis

KONG Weixuan; YANG Pengjie; WEI Qiyou; ZHU Benben

doi:10.13730/j.issn.2097-2148.2023.12.002

Abstract：Objective To observe the ferroptosis levels and inflammatory indexes in model of mice with acute lung injury(ALI)induced by cecal ligation and puncture(CLP);to observe changes of ferroptosis level and inflammatory markers in mice after liproxstatin-1 intervening ferroptosis.Methods A total of 24 male C57BL/6 mice were randomly divided into Sham operated group,CLP group,Lip-1 group and CLP+Lip-1 group,with 6 mice in each.The Sham oper-ated group and Lip-1 group underwent sham surgery,the CLP group and CLP+Lip-1 group underwent CLP surgery(the animal model of sepsis was established by cecal ligation+puncture);the Lip-1 group and CLP+Lip-1 group were preop-eratively injected intraperitoneally with liproxstatin-1(0.8 mg/kg),and the same volume of saline was injected into the Sham operated and CLP groups;mice were executed 16 h after surgery,and bronchoalveolar lavage fluid(BALF)and lung tissues were collected.Wet to dry weight ratio(W/D)of the left lung lobe of each mouse was measured,hematoxy-lin-eosin(HE)staining was performed to observe the pathological and morphological manifestations of the right upper lobe of the lungs of each group of mice,expressions of total protein concentration,tumour necrosis factor al-pha(TNF-α)and interleukin 6(IL-6)in BALF were de-tected.The protein expressions of glutathione peroxidase 4(GPX4),cyclooxygenase 2(COX-2)and acetyl coen-zyme A synthetase long-chain family 4(ACSL4)were detected in the lung tissues of mice in each group by Western blot.The expressions of malondialdehyde(MDA)and 4-Hydroxynonenal(4-HNE)in mice lung tissues were detected by im-munohistochemistry.The expression of ferric ion was detected by reagant.Results Compared with Sham operated group,W/D of lung tissue in mice of CLP group statistically increased(P＜0.01);pathological sections showed that bronchial wall of CLP group was severely congested,and there were obvious inflammatory cell infiltration,severe alveolar wall congestion,obvious lung fibrosis;expressions of total protein concentration,IL-6 and TNF-α in BALF of CLP group statistically increased(all P＜0.01),the expression of GPX4 decreased,while the expressions of ACSL4,COX-2,MDA,4-HNE and content of iron ion significantly increased(all P＜0.05).Compared with CLP group,W/D of lung tissues in CLP+Lip-1 group significantly decreased(P＜0.01);the pathological sections showed that the CLP+Lip-1 group had bronchial wall congestion and small amount of obvious inflammatory cell infiltration,a few alveolar wall con-gestion,mild pulmonary fibrosis,and the therapeutic effects were remarkable;the expressions of total protein concentra-tion,IL-6 and TNF-α in BALF in CLP+Lip-1 group significantly decreased(all P＜0.01),the expression of GPX4 in-creased,while the expressions of ACSL4,COX-2,MDA,4-HNE and content of iron ion significantly decreased(all P＜0.05).Conclusion Ferroptosis is involved in sepsis-induced ALI,and inhibition of ferroptosis can play a certain role in the treatment of sepsis-induced ALI.