FIGURE 2.

Insulin-containing SF microparticles promote diabetic wound healing. (A) The SEM and cross-sectional views of SF microparticles, insulin-encapsulated SF microparticles, and microparticle-loaded SF. (B) Cumulative FITC–insulin release from microparticle-loaded SF dressings. (C,D) Insulin promoted healing of diabetic wound. After the wounding procedure, the wounds in the control group (Ctrl) were dressed with SF microparticles without insulin; wounds were dressed with the insulin-containing SF microparticles in the insulin group (INS). Wound sizes were recorded on the 1st, 5th, and 11th days after wounding using transparent tracing papers. The unhealed rate of wounds was calculated by Image Pro Plus. Data are shown as mean ± SD. **p < 0.01, n = 5. (E,F) Insulin-containing dressing enhances reepithelialization of diabetic wounds. Reepithelialization was analyzed on the 5th and 11th day of wounding. The migration length of the tongue was calculated by Image Pro Plus. Data are shown as mean ± SD. **p < 0.01, n = 5. (G) Insulin-containing dressing alleviates aberrant angiogenesis of diabetic wounds. Angiogenesis quality of the 5th-day wounds was evaluated by H&E observation. (H–J) Insulin-containing dressing promotes collagen deposition of diabetic wounds. Masson trichrome staining was used to check collagen deposition in the wound. The integrated density and positive area of collagen deposition were calculated, and data are shown as mean ± SD. **p < 0.01, n = 5. (K,L) The thickness of the granular tissue was used as a marker of ECM deposition. Data are shown as mean ± SD. **p < 0.01, n = 5.