氢对重度烧伤大鼠肺损伤时细胞焦亡的影响

Effect of hydrogen on cell pyroptosis during lung injury in severely burned rats

目的评价氢对重度烧伤大鼠肺损伤时细胞焦亡的影响。方法清洁级健康成年雄性SD大鼠48只,体质量200~230 g,6~7周龄,采用随机数字表法分为4组(n=12):假手术组(SH组)、假手术+氢气组(SH+H_(2)组)、烧伤组(B组)和烧伤+氢气组(B+H_(2)组)。B组和B+H_(2)组制备大鼠背部(约40%全身体表面积)Ⅲ度烧伤模型,SH组和SH+H_(2)组大鼠仅背部脱毛用烫头以皮温接触。于烧伤后1和6 h时,SH+H_(2)组和B+H_(2)组大鼠分别在此环境中吸入2%氢气1 h。于烧伤后12和24 h时处死大鼠取肺组织,HE染色并评估肺损伤病理学评分,采用ELISA法测定肺组织IL-1和IL-18含量,采用Western blot法检测肺组织NOD样受体热蛋白结构域相关蛋白3(NLRP3)、caspase-1和Gasdermin D蛋白(GSDMD)的表达。结果与SH组比较,B组烧伤后12和24 h时肺损伤病理学评分升高(P<0.05);与B组比较,B+H_(2)组烧伤后12和24 h时肺损伤病理学评分降低(P<0.05);与SH组比较,B组和B+H_(2)组烧伤后12和24 h时肺组织IL-1β和IL-18含量升高,NLRP3、caspase-1和GSDMD表达上调(P<0.05);与B组比较,B+H_(2)组烧伤后12和24 h时肺组织IL-1β和IL-18含量降低,NLRP3、caspase-1和GSDMD表达下调(P<0.05)。结论氢减轻重度烧伤大鼠肺损伤的机制可能与抑制细胞焦亡有关。

Objective To evaluate the effect of hydrogen on cell pyroptosis during lung injury in severely burned rats.Methods Forty-eight clean-grade healthy adult male Sprague-Dawley rats,weighing 200-230 g,aged 6-7 weeks,were divided into 4 groups(n=12 each)by the random number table method:sham operation group(SH group),sham operation+hydrogen group(SH+H_(2)group),burn group(B group)and burn+hydrogen group(B+H_(2)group).In group B and group B+H_(2),theⅢdegree burn model of the back(about 40%of the total body surface area)was prepared in anesthetized animals.The back was shaved and then subjected to a perm at skin temperature in group SH and group SH+H_(2).Rats were exposed to 2%hydrogen for 1 h starting from 1 and 6 h after burn in SH+H_(2)group and B+H_(2)group,respectively.At 12 and 24 h after burn,the rats were sacrificed and lung tissues were obtained for examination of pathological changes which were scored and for determination of the contents of interleukin-1beta(IL-1β)and IL-18 in lung tissues(by enzyme-linked immunosorbent assay)and expression of NOD-like receptor thermal protein domain associated protein 3(NLRP3),caspase-1 and Gasdermin D protein(GSDMD)in lung tissues(by Western blot).Results Compared with SH group,the pathological scores were significantly increased at 12 and 24 h after burn in group B(P<0.05).The pathological scores were significantly decreased at 12 and 24 h after burn in group B+H_(2)as compared with group B(P<0.05).Compared with SH group,the contents of IL-1βand IL-18 in lung tissues were significantly increased at 12 and 24 h after burn,and the expression of NLRP3,caspase-1 and GSDMD was up-regulated in B and B+H_(2)groups(P<0.05).Compared with group B,the contents of IL-1βand IL-18 in lung tissues were significantly decreased at 12 and 24 h after burn,and the expression of NLRP3,caspase-1 and GSDMD was down-regulated in group B+H_(2)(P<0.05).Conclusions The mechanism by which hydrogen attenuates lung injury may be related to inhibition of cell pyroptosis in severely burned rats.