Cutaneous wound healing in type 2 diabetes db/db mice was impaired with specific changes in proinflammatory cytokine expression.

In db/db mice, cutaneous wound healing was delayed, and excessive wound exudates enlarged the wound. However, the relationship between enlarged wounds and proinflammatory cytokine expression remains unknown. Therefore, we investigated the expression of proinflammatory cytokines Tnf-α and Il-6 in cutaneous wound healing with diabetes. In this study, 12 C57BL/6J mice (wild-type: WT) and 14 db/db mice were subjected to full-thickness wound injuries. Wound healing was assessed until day 14, and wound tissues were harvested on days 7, 9, 11, and 14. The wound areas increased for 4 days, gradually increased until day 9, and stabilized until day 14 in the db/db group, but increased for 3 days, rapidly decreased until day 12, and gradually decreased until day 14 in the WT group. On day 14, the wound area in the db/db group was significantly larger than that in the WT group (p < 0.01). The relative expressions of the Tnf-α and Il-6 in the db/db group were significantly higher than those in the WT group on days 7-14, and on days 11 and 14, respectively (p < 0.05). Our study showed that cutaneous wound healing was delayed with wound expansion and the expression of Tnf-α and Il-6 was high throughout the measurement time points in db/db mice. These abnormal expressions could influence impaired cutaneous wound healing in diabetic mellitus.