FIGURE 4.

human fetal secretome‐poly lactic‐co‐glycolic acid (HFS‐PLGA) promote angiogenesis in the dermal injury of streptozotocin (STZ)‐induced diabetic Rat. (a) Representative picture of dermal injure at 7,14,21 days post‐surgery. Scalebar = 1.5 mm; (b) Semi‐quantification result of the wound area. HFS‐PLGA group significantly reduced wound area compared to the control group. The relative wound area of all groups was measured using image J. ANNOVA test, N = 4 *p < 0.05. (c) Higher blood glucose indicates that the STZ induction is successful. Mann–Whitney U *p < 0.05. (d) Representative picture of Masson trichrome staining on wound tissue sections in all time points. Scalebar = 1 mm; (e, f) Semi‐quantification data based on the color intensity of Masson trichrome staining. HFS‐PLGA treatment promoted re‐epithelization at Day 7 post‐surgery and reduced granulation area at Day 22 post‐surgery. Quantitative data were measured using image J. N = 4, Mann–Whitney U test, *p < 0.05; g Representative picture of immunofluorescent staining of Alpha‐SMA and immunohistochemistry staining result of CD31 result in the wound bed. Scalebar = 100 μm. (h,i) Semi‐quantitative result of alpha‐SMA and CD31 expression in the wound bed. HFS‐PLGA group significantly enhanced alpha‐SMA expression at Days 7 and 14 post‐surgery. CD31 were highly stained at Day 7 post‐surgery in HFS‐PLGA group. N = 4. ANNOVA test, *p < 0.05. (j) Representative picture of immunofluorescent staining of NIMP‐R14 and IL‐1βin the wound bed. HFS‐PLGA treatment suppress NIMP‐R14 and IL‐1βexpression at Day 7 post‐surgery. (J) The quantification results confirmed that HFS‐PLGA particles suppress the NIMP‐R14 and IL‐1βat the Days 7 and 14 post‐injury. N = 4. ANNOVA test, *p < 0.05. Brightness and contrast were adjusted for clear demonstrated contents of the representative pictures