背景:糖尿病足溃疡(DFU)是糖尿病引起的主要慢性并发症之一,导致严重病例截肢。DFU中细菌感染影响伤口愈合。
方法:选择符合标准的DFU患者,并详细记录临床资料。收集患者足部伤口的脓液和静脉血进行生化分析。通过16SrRNA测序分析患者脓液中细菌菌群的分布,以及DFU与致病变量之间的相关性,用统计学分析的方法分析其功能和免疫功能。然后,关键细菌对炎症的影响,扩散,凋亡,通过ELISA研究了多形核白细胞的焦亡,CCK-8,流式细胞术,RT-qPCR和蛋白质印迹。
结果:临床数据分析显示,Wagner评分与炎症因子水平呈正相关,有很高的CD3+,CD4+,高Wagner评分的DFU患者CD8+水平低。通过阿尔法,β多样性分析和物种组成分析,棒状杆菌在DFU中占很大比例。Logistics回归模型和Person相关性分析表明,混合细菌感染可加重足部溃疡,细菌数量与炎症因子PCT密切相关,PRT,免疫细胞CD8+,和焦亡相关蛋白GSDMD和NLRP3。通过体外实验,棒状杆菌抑制细胞增殖,促进炎症(TNF-α,PCT,CRP),凋亡和焦亡(IL-1β,LDH,IL-18,GSDMD,NLRP3和胱天蛋白酶-3)。
结论:混合细菌感染加剧了DFU进展,其中棒状杆菌占优势,棒状杆菌促进炎症,凋亡和焦亡抑制DFU愈合。
BACKGROUND: Diabetic foot ulcer (DFU) is one of the main chronic complications caused by diabetes, leading to amputation in severe cases. Bacterial infection affects the wound healing in DFU.
METHODS: DFU patients who met the criteria were selected, and the clinical data were recorded in detail. The pus exudate from the patient\'s foot wound and venous blood were collected for biochemical analysis. The distribution of bacterial flora in pus exudates of patients was analyzed by 16S rRNA sequencing, and the correlation between DFU and pathogenic variables, pyroptosis and immunity was analyzed by statistical analysis. Then, the effects of key bacteria on the inflammation, proliferation, apoptosis, and pyroptosis of polymorphonuclear leukocytes were investigated by ELISA, CCK-8, flow cytometry, RT-qPCR and western blot.
RESULTS: Clinical data analysis showed that Wagner score was positively correlated with the level of inflammatory factors, and there was high CD3+, CD4+, and low CD8+ levels in DFU patients with high Wagner score. Through alpha, beta diversity analysis and species composition analysis,
Corynebacterium accounted for a large proportion in DFU. Logistics regression model and Person correlation analysis demonstrated that mixed bacterial infections could aggravate foot ulcer, and the number of bacteria was closely related to inflammatory factors PCT, PRT, immune cells CD8+, and pyroptosis-related proteins GSDMD and NLRP3. Through in vitro experiments,
Corynebacterium inhibited cell proliferation, promoted inflammation (TNF-α, PCT, CRP), apoptosis and pyroptosis (IL-1β, LDH, IL-18, GSDMD, NLRP3, and caspase-3).
CONCLUSIONS: Mixed bacterial infections exacerbate DFU progression with a high predominance of
Corynebacterium, and
Corynebacterium promotes inflammation, apoptosis and pyroptosis to inhibit DFU healing.