Role of TIPE2 in endotoxin-induced acute lung injury in mice / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the role of tumour necrosis factor-α-induced protein 8-like 2 (TIPE2) in the acute lung injury (ALI) induced by endotoxin in mice.Methods:Forty SPF healthy adult male BALB/c mice, aged 6-8 weeks, weighing 20-25 g, were divided into 4 groups ( n=10 each) using a random number table method: vehicle plasmid group (VP group), vehicle plasmid plus ALI group (VP+ ALI group), TIPE2 adeno-associated virus overexpression group (T group) and TIPE2 adeno-associated virus overexpression plus ALI group (T+ ALI group). The mice in VP and VP+ ALI groups were injected with empty adeno-associated virus, while the mice in T and T+ ALI groups were intratracheally given adeno-associated virus carrying TIPE interference sequence.Three weeks later, the model of endotoxin-induced ALI was established.Lipopolysaccharide (LPS) 5 mg/kg was intratracheally given in VP+ ALI and T+ ALI groups, and the equal volume of phosphate buffered saline (PBS) was given in VP and T groups.Blood samples were obtained from the abdominal aorta at 24 h after injection of LPS for blood gas analysis, oxygenation index (OI) was calculated, and tumor necrosis factor-alpha (TNF-α) in serum were detected by enzyme-linked immunosorbent assay.The animals were then sacrificed, and lung tissues were removed for examination of pathological changes which were scored after haematoxylin and eosin staining, for calculation of the wet/dry weight ratio (W/D ratio) and for determination of myeloperoxidase (MPO) activity and the expression of TIPE2, phosphorylated c-Jun N-terminal kinase (p-JNK) and nuclear factor kappa B(NF-κB) (by Western blot). Results:Compared with VP group, the lung injury score, W/D ratio, MPO activity and concentration of serum TNF-α were significantly increased, PaO 2 and OI were decreased, expression of TIPE2 was down-regulated and expression of p-JNK and NF-κB was up-regulated in VP+ ALI group ( P<0.05). Compared with VP+ ALI group, the lung injury score, W/D ratio, MPO activity and concentration of serum TNF-α were significantly decreased, PaO 2 and OI were increased, expression of TIPE2 was up-regulated and expression of p-JNK and NF-κB was down-regulated in T+ ALI group ( P<0.05). Conclusion:The down-regulation of TIPE2 expression is involved in the process of ALI induced by endotoxin in mice.