瘦素预处理对机械通气肺损伤大鼠NLRC4炎症小体表达的影响

目的:探讨瘦素预处理对机械通气肺损伤(VILI)大鼠NLRC4炎症小体表达的影响。方法:健康雄性SD大鼠36只，体质量200～250 g，6～8周龄，采用随机数字表法分为3组：对照组、VILI模型组和瘦素组，每组12只。对照组麻醉后气管插管并保留自主呼吸；VILI模型组连接小动物呼吸机行机械通气，潮气量40 ml/kg...

Effect of leptinpre treatment on expression of NLRC4 inflammasome in ventilator-induced lung injury rats

Objective To investigate the effect of leptin pretreatment on the expression of NLRC4 inflammasome in ventilator-induced lung injury(VILI)rats.Methods Thirty-six pathogen-free adult male SD rats,weighting 200-250 g,6-8 weeks old,were divided into three groups using a random number table:control group,VILI model group and leptin group,12 rats in each group.The rats in control group had autonomous respiration with air for four hours after being anesthetized.VILI model group received mechanical ventilation through a small animal ventilator with 40 ml/kg tidal volume for four hours.In leptin group,rats was intraperitoneally injected with 50μg/kg recombinant leptin after tracheal intubation,and received mechanical ventilation with 40 ml/kg tidal volume for four hours.At the end of mechanical ventilation,blood samples were collected from the femoral artery for arterial blood gas analysis,and PaO₂ was recorded.The rats were sacrificed to collect remaining blood and bronchoalveolar lavage fluid(BALF).The levels of interleukin-1β(IL-1β)and IL-18 were detected by enzyme-linked immunosorbent assay.The degree of lung pathological damage was observed after hematoxylin-eosin staining under light microscope,and lung injury score was calculated.The wet/dry weight ratio of right middle lobe was calculated.The expressions of caspase-1 and NLRC4 in right lower lobe were detected by Western blot.Results Compared with control group,the pathological injury score,the wet/dry weight ratio,the concentrations of IL-18 and IL-1βin serum and BALF,the protein expressions of caspase-1 and NLRC4 in lung tissues of VILI model group and leptin group were significantly increased(all P<0.01),and PaO₂ was significantly decreased(P<0.01).Compared with VILI model group,the pathological injury score,the wet/dry weight ratio,the concentrations of IL-18 and IL-1βin serum and BALF,the protein expressions of caspase-1 and NLRC4 in lung tissues of leptin group were decreased(all P<0.05),and PaO₂ was increased(P<0.05).Conclusions Exogenous leptin pretreatment can significantly reduce VILI of rats,the mechanism may be related to inhibiting NLRC4 inflammasome activation and reducing the inflammatory response of lung tissues.