S100A12在小鼠脓毒症继发急性肺损伤的表达及功能研究OA

Objective To investigate the expression and function of S100 calcium binding protein A12(S100A12)in sepsis-induced acute lung injury in mice,and to identify potential markers and intervention targets for the treatment of acute lung injury.Methods A total of 48 male C57BL/6 mice were randomly divided into two groups:the cecal ligation and puncture(CLP)group and the sham group(SHAM)group.Two groups of animals were further divided into four subgroups at 4 h,8 h,12 h,and 24 h after the experiment,with 6 animals in each subgroup.The entire length of the cecum in CLP group were ligated,with 3 sterile needle punctures.The SHAM group only underwent laparotomy.Each group of mice was anesthetized at the corresponding time point through intraperitoneal injection of pentobarbital sodium.About 0.5 ml of blood were collected from the mouse heart for preparation of serum.And right lung tissues were collected from the mice.The content of S100A12 protein in mouse serum was detected using the enzyme-linked immunosorbent assay(ELISA)method.The expression level of such mRNA as S100A12,receptor for advanced glycation end products(RAGE),nuclear factor kappa-B(NF-κB)and tumor necrosis factor α(TNF-α)in the right lung of mice was determined using the reverse transcription polymerase chain reaction(RT-PCR)method,And hematoxylin-eosin(HE)staining method was used to observe and obtain histopathologic score of the right lung tissues in mice.Results The mice in CLP group showed signs of congestion and swelling in the lungs,which worsened as the experimental time increased.The lung color tended to be dark red,and there were obvious bleeding spots on the surface of lungs.The lung tissues of the mice in SHAM group were intact,with no obvious bleeding spots on the surface of lungs.The lung color tended to be reddish,with relatively soft tissue texture.There were significant differences between the two groups of mouse specimens.The S100A12 level in the mice serum and lung histopathology score in the CLP group significantly increased at 4 h and reached a peak at 12 h,which were significantly different from the condition in the mice serum in the SHAM group,and the difference was statistically significant(P<0.05).The relative expression level of RAGEmRNA,NF-κB p65 mRNA and TNF-αmRNA in the CLP group was higher than that in the SHAM group,with RAGEmRNA increasing after 8 h of the experiment and reaching its peak value at 12 h.The relative expression level of NF-κB p65 mRNA and TNF-αmRNA significantly increased after 4 h of the experiment,and the difference was statistically significant(P<0.05).Conclusion As sepsis worsens,the lung tissue of mice is damaged,causing significant lung damages.The expression level of S100A12,RAGE,NF-κB and TNF-α will increase,and S100A12 level is positively correlated with inflammatory factors and lung injury,indicating that S100A12 may have a certain relationship with sepsis-induced acute lung injury.