Correlation between apoptosis rate and expression of Bcl-2, Bax and tumor necrosis factor alpha in diabetic foot ulcer with different disease courses / 中国组织工程研究

ABSTRACT

BACKGROUND: Non-healing of refractory ulcer wounds is found to be associated with imbalance of apoptosis and dysregulation of inflammation. Previous studies have sampled a certain type of tissue in different individuals, but individual differences maybe exist among the study data. There is still no report on the correlation between apoptotic rate, expression levels of Bcl-2, Bax, Bax/Bcl-2 and tumor necrosis factor α (TNF-α) in wound tissue of diabetic foot ulcer with different disease courses. OBJECTIVE: To study the relationship between apoptotic rate and expression levels of Bcl-2, Bax and TNF-α in the wound tissue of diabetic foot ulcer with different disease courses and the mechanism of action. METHODS: Fifteen patients with typical diabetic foot of Wagner grades 2-3 were selected from the Department of Emergency, Chongqing Medical University. The wound tissue was classified as necrotic, transitional and normal tissue using the "4C” method after infection control. The apoptotic rate and levels of Bcl-2, Bax, TNF-α and Bax/Bcl-2 were detected using immunohistochemistry, and the results were statistically analyzed. The study protocol was approved by the Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University, with the approval No. (2019)329. All patients signed an informed consent. RESULTS AND CONCLUSION: The apoptotic rates of normal, transitional and necrotic tissues of diabetic foot were significantly different, which were (16.67±2.48)%, (43.68±2.22)% and (72.12±4.53)%, respectively (P transitional tissue > normal tissue. There was a curve relationship between Bcl-2, Bax, Bax/Bcl-2, TNF-α expression and apoptotic rate. The curvilinear regression analysis indicated that the expression of TNF-α had a highly positive correlation with the expression of Bax and Bax/Bcl-2 and had a highly negative correlation with the expression of Bcl-2. Therefore, apoptotic mechanism and inflammatory reaction are involved in the pathological process of diabetic food ulcer, and the mechanism may be related to the down-regulation of Bcl-2 expression, up-regulation of Bax and TNF-α expression, and increase of Bax/Bcl-2, thereby increasing the apoptotic rate.