长链非编码RNA FAM224B对大鼠重症肺炎肺组织的保护作用及机制研究

Long chain noncoding RNA FAM224B protects the lung tissue of rats with severe pneumonia and the underlying mechanism

目的探讨过表达长链非编码RNA(lncRNA)FAM224B对大鼠重症肺炎肺组织的保护作用及机制。方法研究时间为2020年8月至2021年3月,将20只大鼠采用随机数字表法分为肺炎组(重症肺炎模型)和FAM224B组(重症肺炎模型+FAM224B质粒),每组10只。实时定量聚合酶链式反应(qRT-PCR)测定肺组织FAM224B水平,酶联免疫吸附测定法(ELISA)检测肺组织匀浆中肿瘤坏死因子α(TNF-α)、白细胞介素(IL)6、IL-1β水平,生物信息学软件starBase v2预测FAM224B的靶基因,qRT-PCR检测肺组织靶基因的表达,Western blot检测肺组织核因子-κB(NF-κB)信号通路蛋白表达。结果肺炎组、FAM224B组肺组织中FAM224B表达分别为(1.09±0.23)、(10.12±1.52),肺炎组FAM224B表达明显低于FAM224B组(t=15.86,P<0.01)。肺炎组肺组织匀浆中TNF-α、IL-6、IL-1β分别为(41.53±2.46)μg/L、(34.01±2.53)ng/L、(20.92±1.95)μg/L,FAM224B组分别为(21.71±2.25)μg/L、(17.13±3.01)ng/L、(11.97±1.21)μg/L,两组差异均有统计学意义(t=15.94、14.29、13.89,均P<0.01)。FAM224B与miR-34b-5p存在互补结合位点。与肺炎组比较,FAM224B组肺组织中miR-34b-5p表达明显降低(t=15.55,P<0.01),磷酸化核因子-κB亚单位(p-p65)、磷酸化核因子κB抑制蛋白α(p-IKB-α)蛋白表达降低。结论过表达FAM224B通过抑制miR-34b-5p可减轻大鼠重症肺炎肺组织的炎性反应。

Objective To investigate the protective effects of overexpression of long-chain noncoding RNA FAM224B on lung tissue of rats with severe pneumonia and the underlying mechanism.Methods From August 2020 to March 2021,we randomly allocated 20 rats into the pneumonia group(severe pneumonia modeling)and FAM224B group(severe pneumonia modeling+FAM224B plasmid),with 10 rats in each group.We performed a quantitative real-time polymerase chain reaction to detect the level of FAM224B in lung tissue and performed an enzyme-linked immunosorbent assay to detect the levels of tumor necrosis factor-alpha,interleukin-6,and interleukin-1βin lung tissue.We used the software starBase v2.0 to predict the target gene of FAM224B.We performed a quantitative real-time polymerase chain reaction to detect the expression of the target gene in lung tissue and performed a western blot assay to detect the protein expression of the nuclear factor-kappa B signal pathway in lung tissue.Results FAM224B expression was(1.09±0.23)and(10.12±1.52)in the pneumonia and FAM224B groups,respectively.FAM224B expression was significantly lower in the pneumonia group compared with the FAM224B group(t=15.86,P<0.01).The levels of tumor necrosis factor-alpha,interleukin-6,and interleukin-1βwere(41.53±2.46)μg/L,(34.01±2.53)ng/L,(20.92±1.95)μg/L in the pneumonia group and they were(21.71±2.25)μg/L,(17.13±3.01)ng/L,(11.97±1.21)μg/L in the FAM224B group.There were significant differences in the levels of tumor necrosis factor-alpha,interleukin-6,and interleukin-1βbetween the two groups(t=15.94,14.29,13.89,all P<0.01).FAM224B had complementary binding sites with miR-34b-5p.The expression level of miR-34b-5p in lung tissue was significantly lower in the FAM224B group compared with the pneumonia group(t=15.55,P<0.01).The protein expression levels of phosphorylated nuclear factor-κB subunit(p-p65)and phosphorylated inhibitor of kappa B alpha in lung tissue were significantly lower in the FAM224B group compared with the pneumonia group.Conclusion FAM224B overexpression reduces the inflammatory reaction in lung tissue of rats with severe pneumonia through inhibiting miR-34b-5p expression.