动物造模,急性肺损伤 z-bio 2022-02-12 664

　　Objective To investigate the effect of down-regulation of miR-128-3p on inflammatory response and lung histomorphology in acute lung injury in septic rats.

　　Methods Sixty healthy 3-week-old SD rats were selected and randomly divided into: sham operation group, sepsis model group, blank transfection group and miR-128-3p silence group, with 15 rats in each group. Except for the sham-operated group, rats in each group were treated with cecal ligation and puncture to prepare a rat sepsis model; in the blank transfection group, a blank plasmid was constructed and transfected into rats; in the miR-128-3p silencing group, a lentiviral plasmid was constructed and transfected into large mouse. RT-PCR was used to detect the expression of miR-128-3p to confirm that the interference was successful; the resting ventilation, airway resistance and lung volume changes were detected in each group of rats; ELISA was used to detect the levels of IL-6, TNF-α and iNOS in peripheral serum. Lung epithelial tissue fibrosis and pathological damage were observed by HE staining; the expression of Caspase-3 and Caspase-9 in lung tissue was detected by TUNEL staining combined with Western blotting; TGF-β and α- SMA expression.

　　Results The HE staining results showed that the cells in the miR-128-3p silencing group were evenly distributed, and there were fewer necrotic cells. The results of MASSON staining showed that the lung tissue of the sepsis model group had severe fibrosis and damage, and the degree of fibrosis of the lung tissue of the miR-128-3p silencing group was improved. Compared with the sham operation group, the miR-128-3p expression, airway resistance, IL-6 content level, iNOS content level, TNF-α content level, lung tissue apoptosis rate, cleaved cas3/ The relative expression of Caspase-3, cleaved cas9/Caspase-9, TGF-β protein and α-SMA protein were significantly increased (P<0.05), and the resting ventilation, airway resistance and lung volume were significantly decreased (P<0.05). P<0.05). Compared with the blank transfection group, the expression of miR-128-3p, airway resistance, IL-6 content, iNOS content, TNF-α content, lung tissue apoptosis rate, cleaved cas3 in miR-128-3p silencing group / Caspase-3, cleaved cas9 / Caspase-9, the relative expression of TGF-β protein and the relative expression of α-SMA protein were significantly decreased (P<0.05), and the resting ventilation, airway resistance changes and lung volume changes were significantly increased (P<0.05).

　　Conclusion Down-regulation of miR-128-3p can alleviate acute lung injury in rats with sepsis, and its mechanism may be related to reducing the inflammatory response in rats and inhibiting the apoptosis of lung tissue cells.