Wang Yuyu, Huang Jianjiang, Zhang Fang, Shen Keli, Qiu Bin
Department of Critical Care Medicine, Shengzhou People's Hospital, the First Affiliated Hospital of Zhejiang University Shengzhou Branch, Shengzhou, Zhejiang, China.
Growth Factors. 2023 Oct;41(4):210-220. doi: 10.1080/08977194.2023.2259497. Epub 2023 Oct 19.
To observe the mechanism of IGFBP2 knock-down in improving lung fibrosis and inflammation through STAT3 pathway in rats with severe pneumonia.
First, SP rat model was established. Then rats were divided into the Control group, the SP group, the SP + Lv-vector shRNA group, the SP + Lv-IGFBP2 shRNA group, the SP + Lv-vector group, and the SP + Lv-IGFBP2 group. The mRNA and protein levels of IGFBP2, NOS, CD206 and Arg 1 were detected by RT-qPCR and Western blot. IHC was used to check the positive expression of IGFBP2 and MCP1. A fully automated blood gas analyzer was used to detected PaCO, CO content, PaO2 and SaO2. HE and Masson staining were performed to observe the lung tissue injury and collagen deposition of rats in each group. ELISA assays were used to calculate the levels of inflammatory factors IL-1β, IL-6, TNF-α, IL-4, and IL-10. Flow cytometry was conducted to acquire the ratio of M1-type AMs and M2-type AMs.
Compared with the Control group, IGFBP2, iNOS, CD206, and Arg1 mRNA and protein expression levels, IGFBP2 and MCP1 positive expressions, PaCO, p-STAT3/STAT3, p-JAK2/JAK2, IL-1β, IL-6, and TNF-α levels, the number of AMs and neutrophils, the proportion of M1 type AMs and the expressions of α-SMA, Collagen-I, Collagen III, and Fibronectin were significantly increased in SP rats < 0.05), while PaCO, CO, and SaO, IL-4 and IL-10 levels, and the proportion of M2 type AMs decreased ( < 0.05). However, the knockdown of IGFBP2 reversed the above index trends.
Knock-down of IGFBP2 ameliorated lung injury in SP rats, inhibited inflammation and pulmonary fibrosis, and promoted M2-type transformation of AMs by activating the STAT3 pathway.
观察敲低IGFBP2通过STAT3通路改善重症肺炎大鼠肺纤维化和炎症的机制。
首先，建立SP大鼠模型。然后将大鼠分为对照组、SP组、SP + Lv-载体shRNA组、SP + Lv-IGFBP2 shRNA组、SP + Lv-载体组和SP + Lv-IGFBP2组。采用RT-qPCR和Western blot检测IGFBP2、NOS、CD206和Arg 1的mRNA和蛋白水平。免疫组化法检测IGFBP2和MCP1的阳性表达。使用全自动血气分析仪检测PaCO、CO含量、PaO2和SaO2。进行HE和Masson染色以观察各组大鼠肺组织损伤和胶原沉积情况。采用ELISA法计算炎症因子IL-1β、IL-6、TNF-α、IL-4和IL-10的水平。通过流式细胞术获取M1型AMs和M2型AMs的比例。
与对照组相比，SP大鼠中IGFBP2、iNOS、CD206和Arg1的mRNA和蛋白表达水平、IGFBP2和MCP1阳性表达、PaCO、p-STAT3/STAT3、p-JAK2/JAK2、IL-1β、IL-6和TNF-α水平、AMs和中性粒细胞数量、M1型AMs比例以及α-SMA、Collagen-I、Collagen III和Fibronectin的表达均显著升高（P < 0.05），而PaCO、CO和SaO、IL-4和IL-10水平以及M2型AMs比例降低（P < 0.05）。然而，敲低IGFBP2逆转了上述指标趋势。
敲低IGFBP2可改善SP大鼠的肺损伤，抑制炎症和肺纤维化，并通过激活STAT3通路促进AMs向M2型转化。
