铜绿假单胞菌感染的糖尿病足患者创面肉芽组织中自噬相关蛋白的表达

Autophagy-related protein expressions in wound granulation tissues from diabetic foot patients infected with Pseudomonas aeruginosa

目的观察铜绿假单胞菌（Pseudomonas aeruginosa，PA）感染的糖尿病足患者创面肉芽组织中自噬相关蛋白LC3及Beclin-1的表达水平，初步探讨糖尿病状态下铜绿假单胞菌多重耐药性与自噬相关蛋白表达水平的关系。 方法选取2015年4月至2016年3月在天津医科大学代谢病医院足病科住院治疗的PA感染的糖尿病足患者（DF组）共31例。以同时期在天津武警医院烧伤科住院治疗的PA感染的足部烧伤患者为非糖尿病对照组（CON组）共19例。取2组患者足部创面肉芽组织，应用免疫组化检测LC3及Beclin-1的表达，免疫荧光双染检测巨噬细胞内LC3的表达。结果与CON组相比，DF组患者创面肉芽组织中LC3及Beclin-1表达明显减弱（1.75±0.36对2.44±0.33，0.75±0.22对1.46±0.21，均P〈0.01），且巨噬细胞内LC3表达减弱。与CON组相比，DF组多重耐药铜绿假单胞菌（Multi-drug resistant pseudomonas aeruginosa，MDRPA）的检出率较高（48.4%对5.3%，P〈0.01）；在DF组中，与非MDRPA组相比，MDRPA组患者肉芽组织中LC3及Beclin-1表达明显减弱（1.62±0.08对1.91±0.13，0.62±0.11对0.89±0.14，均P〈0.01）。结论PA感染的糖尿病足患者创面肉芽组织中自噬相关蛋白LC3及Beclin-1表达下降，且MDRPA感染的糖尿病足患者中表达更低，糖尿病足患者铜绿假单胞菌多重耐药性可能与自噬相关蛋白表达水平减弱有关。

Objective To observe LC3 and Beclin-1 protein expressions in granulation tissues of diabetic foot（DF）patients infected with Pseudomonas aeruginosa（PA）, and to explore the relationship between the multi-drug resistance of pseudomonas aeruginosa and autophagy-related protein expressions in diabetes mellitus. Methods Thirty-one DF inpatients infected with PA in Tianjin Metabolic Diseases Hospital from April 2015 to March 2016 were enrolled（DF group）and 19 inpatients with foot burn infected with PA in Tianjin Armed Police Hospital at the same period were enrolled as non-diabetic control group（CON）. Immunohistochemistry was used to determine the expressions of LC3 and Beclin-1 in wound granulation tissues taken from these patients. The expression of LC3 in macrophages was detected by an immunofluorescence double staining method.Results Compared with CON group, the expressions of LC3 and Beclin-1 in DF group were significantly decreased（1.75±0.36 vs 2.44±0.33, 0.75±0.22 vs 1.46±0.21, both P〈0.01）, and the expression of LC3 in macrophages were also decreased. Compared with CON group, higher percentage of the detection rate of multi-drug resistant pseudomonas aeruginosa（MDRPA）was found in DF group（48.4% vs 5.3%, P〈0.01）. In DF group, LC3 and Beclin-1 expressions in granulation tissues of MDRPA group were lower than those of Non-MDRPA group（1.62±0.08 vs 1.91±0.13, 0.62±0.11 vs 0.89±0.14, both P〈0.01）.Conclusions The LC3 and Beclin-1 expressions in wound granulation tissues of DF patients infected with PA are decreased compared with control patients, especially in DF patients infected with MDRPA. The multi-drug resistance of pseudomonas aeruginosa in diabetic foot infection is related to reduced autophagy-related protein expression levels.