(A) Four groups of wounded diabetic mice were treated daily with PBS, HBO, SDF-1α, or HBO+SDF-1α. The fraction of initial wound size was measured daily by digital photography and analyzed with ImageJ for 6 days after wounding. Each point represents the mean of 5 experiments. Diabetic mice treated with SDF-1α+HBO had significantly improved wound healing rates at all time points when compared with PBS-treated controls (*P < 0.001 at days 1–5; **P < 0.05 at day 6). Diabetic mice treated with either HBO or SDF-1α demonstrated significantly improved wound healing over PBS controls at days 2, 3, and 5 (^#P < 0.05). (B) Representative wounds at days 0, 3, and 6 are shown for each group. (C) Trichrome staining of wound tissues at day 6. Collagen was stained as blue. (D) Quantification of collagen content. Data are based on 5 scanned slides in each group at day 6. Data are based on 3 experiments. SDF-1α+HBO–treated mice demonstrated a significant rise in wound vessel density and collagen deposit compared with individual treatments alone (*P < 0.05), while SDF-1α and HBO treatments alone had significant increases compared with PBS control (**P < 0.05) at day 6. (E) Effect of timing in the initiation of SDF-1α+HBO therapy on wound healing in diabetic mice. Wound closure rates were monitored when treatment was started at days 0, 1, 3, and 5 after wounding and compared with the PBS treated group. Early treatment (days 0 and 1) was necessary to achieve increased closure rate.