Combined effects of photobiomodulation and curcumin on mast cells and wound strength in wound healing of streptozotocin-induced diabetes in rats.

We investigated the probable involvement of mast cell degranulation and their numbers in the remodeling step of wound healing in a diabetic ischemic skin wound model treated with photobiomodulation plus curcumin. A total of 108 adult male Wistar rats were randomized into one healthy control and five diabetic groups. Type I diabetes was inflicted in 90 of the 108 rats. After 1 month, an excisional wound was generated in each of the 108 rats. There were one healthy group (group 1) and five diabetic groups as follows: group 2 was the untreated diabetic control group and group 3 rats were treated with sesame oil. Rats in group 4 were treated with photobiomodulation (890 nm, 890 ± 10 nm, 80 Hz, 0.2 J/cm2) and those in group 5 received curcumin dissolved in sesame oil. Group 6 rats were treated with photobiomodulation and curcumin. We conducted stereological and tensiometric tests on days 4, 7, and 15 after treatment. The results indicated that photobiomodulation significantly improved wound strength in the diabetic rats and significantly decreased the total numbers of mast cells. The diabetic control group had significantly reduced tensiometric properties of the healing wounds and a significant increase in the total numbers of mast cells. Photobiomodulation significantly improved the healing process in diabetic animals and significantly decreased the total number of mast cells. The increased numbers of mast cells in the diabetic control group negatively affected tensiometric properties of the ischemic skin wound.