Intensive Care Unit, The Fourth People's Hospital of Qinghai Province, Xining, Qinghai 810000, P.R. China.
Intensive Care Unit, The Fourth People's Hospital of Qinghai Province, Xining, Qinghai 810000, P.R. China.
Int J Mol Med. 2021 Dec;48(6). doi: 10.3892/ijmm.2021.5050. Epub 2021 Oct 19.
Matrix metalloproteinase (MMP)‑9 is associated with the severity of ventilator‑associated pneumonia (VAP), while an rs1056629 SNP located in the 3'‑untranslated region (UTR) of MMP‑9 affects the microRNA (miRNA/miR)‑491‑mediated regulation of MMP‑9 expression. In the present study, the effect of rs1056629 on the development of VAP in patients with chronic obstructive pulmonary disease (COPD) was investigated. Patients with COPD were enrolled in the study and their genotypes of rs1056629 (CC, CA or AA) were determined. ELISA was used to analyze the levels of TNF‑α and IL‑6 in the monocytes of patients with COPD carrying differential genotypes of rs1056629. Reverse transcription‑quantitative PCR was carried out to evaluate the expression of miR‑491 and MMP‑9 mRNA in the different groups of patients with COPD. Luciferase assay was used to confirm the inhibitory role of miR‑491 in MMP‑9 expression. Western blot analysis was carried out to assess the expression of MMP‑9 protein in A549 and H1299 cells transfected with miR‑491 mimics. The risk and severity of VAP were significantly elevated in patients with COPD carrying the CC and AC genotypes of rs1056629. Although there was no difference in the expression of miR‑491 in patients carrying different genotypes of rs1056629, the expression levels of TNF‑α, IL‑6 and MMP‑9 were increased in patients with COPD carrying the CC and AC genotypes of rs1056629. The results of luciferase assay revealed that miR‑491 inhibited the expression of MMP‑9 through direct binding to the 3'UTR of MMP‑9. Transfection of miR‑491 mimics into A549 and H1299 cells markedly suppressed the expression of MMP‑9 in a concentration‑dependent manner. On the whole, the findings of the present study confirm that the CC and AC genotypes of rs1056629 increase the risk of developing VAP in patients with COPD by increasing the expression of MMP‑9.
基质金属蛋白酶（MMP）-9 与呼吸机相关性肺炎（VAP）的严重程度相关，而 MMP-9 3'非翻译区（UTR）中的 rs1056629 单核苷酸多态性（SNP）影响 miRNA（miRNA/miR）-491 对 MMP-9 表达的调节。本研究探讨了 rs1056629 对慢性阻塞性肺疾病（COPD）患者 VAP 发展的影响。招募了 COPD 患者，并确定了他们 rs1056629（CC、CA 或 AA）的基因型。采用 ELISA 法分析了携带不同 rs1056629 基因型的 COPD 患者单核细胞中 TNF-α和 IL-6 的水平。采用逆转录-定量 PCR 评估了不同 COPD 患者组 miR-491 和 MMP-9 mRNA 的表达。采用荧光素酶报告基因实验证实了 miR-491 对 MMP-9 表达的抑制作用。采用 Western blot 分析评估了转染 miR-491 模拟物的 A549 和 H1299 细胞中 MMP-9 蛋白的表达。携带 rs1056629 CC 和 AC 基因型的 COPD 患者的 VAP 风险和严重程度显著升高。尽管携带不同 rs1056629 基因型的患者 miR-491 的表达无差异，但携带 rs1056629 CC 和 AC 基因型的 COPD 患者的 TNF-α、IL-6 和 MMP-9 表达水平升高。荧光素酶报告基因实验结果显示，miR-491 通过与 MMP-9 的 3'UTR 直接结合抑制 MMP-9 的表达。miR-491 模拟物转染 A549 和 H1299 细胞后，MMP-9 的表达呈浓度依赖性显著下调。综上所述，本研究结果证实，rs1056629 的 CC 和 AC 基因型通过增加 MMP-9 的表达，增加了 COPD 患者发生 VAP 的风险。
