To explore the expression of the TGF-β1 of diabetic foot wound granulation tissue treated by negative pressure wound therapy(NPWT), which with mild or moderate peripheral artery disease.

Forty three patients at Bethune International Peace Hospital of People′s Liberation Army with diabetic foot ulcers from January 2014 to February 2018 were enrolled in this study and divided into moderate ischemia group [23 cases, 0.5≤ankle-brachial index (ABI)<0.7] and mild ischemia group (20 cases, 0.7≤ABI<0.9) according to the ABI. Granulation tissue biopsies were taken before and 14 days after treatment, which were all divided into three parts: one part were preserved in 4% paraformaldehyde at 4 ℃ for immunohistochemical staining when all specimens collected; the other two parts were transferred in liquid nitrogen to the laboratory immediately and preserved in refrigerator at -80 ℃ for Western blotting and Real-time PCR respectively. Date were compared with independent sample t test.

Immunohistochemical staining showed that optical density of TGF-β1 after 14 days treatment in both moderate and mild ischemia group were higher than those before treatment, the differences were statistically significant (with P values below 0.05), with the increase in mild ischemia group (63.09±10.96)% more significant than moderate ischemia group[(38.71±12.78)%], the difference was statistically significant (t=-6.66, P<0.05). Western blotting showed those the expression of TGF-β1 protein after 14 days treatment were higher than that before treatment in both moderate and mild ischemia group, the differences were statistically significant (with P values below 0.05), compared with the increase in mild ischemia group (50.31±25.64)%, the degree of change in the mild ischemic group [(85.44±27.78)%] was significant, the difference was statistically significant (t=-4.31, P<0.05). Real-time PCR showed that the expression of TGF-β1 gene after 14 days treatment were higher than those before treatment in both moderate and mild ischemia group, the differences were statistically significant (with P values below 0.05). Compared with the change amplitude of the moderate ischemic groups [(73.85±41.22)%], the increase the mild ischemic group [(129.78±36.71)%] was significant, the difference was statistically significant (t=-4.67, P<0.05).

NPWT can promote the expression of TGF-β1 in granulation tissue of diabetic patients with mild and moderate ischemic wounds, moreover, the promotion of TGF-β1 expression in granulation tissue of diabetic foot with mild ischemic wound is better than that of moderate ischemic wound.