Expression Of Deleted In Malignant Brain Tumors 1 Protein In Acute Respiratory Distress Syndrome RATs Caused By Sepsis

Objectives Acute Respiratory Distress Syndrome(ARDS)is a severe form of respiratory failure with high mortality.However,there is a lack of effective biomarkers to assist in the early diagnosis,condition evaluation and treatment monitoring of ARDS.This project plans to establish a septic ARDS rat model through CLP,observe the expression changes of DMBT1 and ARDS related markers,and explore the possible mechanism of DMBT1,in order to provide experimental basis for DMBT1 as a biomarker for the early diagnosis,severity evaluation and treatment target of ARDS.Methods Fifty-six healthy male Wistar rats aged 6 to 8 weeks were used to establish septic ARDS model by CLP as the research object,and were divided into normal control group(Con group),Sham group(Sham group)and cecal ligation and perforation group(CLP group).The rats were sampled at 6h,12 h and 24 h after CLP and sham operation,and the general conditions of rats were observed,the wet-dry weight ratio of lung was measured,the pathological morphology of lung tissues was observed by HE staining,and the concentrations of DMBT1,IL-6,IL-10,SP-A and VEGF in serum were detected by ELISA.Expression of DMBT1,SP-A,VEGF,IL-6,IL-10 protein and m RNA in lung tissue were respectively detected by Western blot and q RT-PCR.Pearson correlation analysis was used to analyze the relationship between serum DMBT1 and the concentrations of IL-6,IL-10,SP-A and VEGF.Results 1 Rats general performance: rats in Con group were normally active and responsive,while rats in the Sham group had no significant changes after surgery compared with the Con group.After 6h~8h,the rats in CLP group gradually developed cyanotic limbs,respiratory distress,decreased activity,erect hair,slow response to stimulation,abdominal distension and other symptoms.2 Wet and dry weight ratio: Compared with Con group,lung wet/dry weight ratio of Sham group had no significant change,CLP group gradually increased at 6h,12 h and 24 h postoperatively,and significantly increased at 12 h and 24 h postoperatively compared with Con group(P<0.05).3.Lung tissue HE staining: In the Con group,the alveolar structure was intact and clear,while in the Sham group,the lung interstitium was slightly widened,and there was no bleeding and exudation in the alveolar cavity.CLP group showed alveolar structural damage,alveolar membrane thickening and destruction,alveolar fusion,a large number of inflammatory cell infiltration,pink fluid and a large number of red blood cells in the alveolar cavity.4 ELISA concentration change results: DMBT1 and SP-A,VEGF,IL-6,IL-10 in CLP group showed A similar trend of serum concentration change,with the aggravation of clinical symptoms at 6h,12 h,24h after surgery,showing an increasing trend.DMBT1 increased significantly in the early 6 hours after treatment(P<0.05).5 q RTPCR detected changes of m RNA expression: there were no significant changes in the m RNA expression of the five markers in the lung tissues of the Sham group when compared to the Con group.The expression changes of the five markers increased in the CLP group with increasing treatment time,and the DMBT1 m RNA 6h expression levels were 2 times higher than the Con group,the expression level was higher than other indicators.6 Western-Blot analysis results: compared with Con group,there was no significant change in the expression of DMBT-1,SP-A,VEGF biomarkers of protein level in Sham group.In the CLP group,the expression of DMBT1,SP-A,and VEGF proteins was increased at 6h,12 h,and 24 h,and the multiple increase of DMBT1 was higher than that of SP-A and VEGF.7 Relative analysis of DMBT1 and other indicators: there was no correlation between serum DMBT1 and IL-6(r=0.562),IL-10(r=-0.123),SP-A(r=0.020),VEGF(r=-0.476),and lung injury scores(r=-0.014)in Con group rats(P>0.05).There was positive correlation between serum DMBT1 and IL-10(r=0.833),lung injury scores(r=0.892)in CLP group rats at 6h(P<0.05).There was positive correlation between serum DMBT1 and IL-10(r=0.842),SP-A(r=0.897),VEGF(r=0.925),and lung injury scores(r=0.943)in CLP group rats at 24h(P<0.05).Conclusions 1 Cecal ligation and puncture successfully constructed septic ARDS rat model.2 DMBT1 may be a biomarker for early diagnosis and severity assessment of ARDS.3 DMBT1 may be involved in the pathogenesis of ARDS by affecting inflammatory reactions,permeability of alveolar epithelium and capillary,and surfactant activity.Figure 11;Table 12;Reference 135...