Wound healing is interaction of a complex cascade of cellular/biochemical actions leading to restoration of structural and functional integrity with regain of injured tissues strength. This study was aimed at evaluation of application of ethanolic extract of propolis-loaded poly(-lactic-co-glycolic acid) nanoparticles (EEP-PLGA NPs) on wound healing in diabetic rats. Sixty rats were randomized into four groups of 15 rats each: In control group (Control) diabetic wound was treated with normal saline. In Carrier 1 group diabetic wound was treated with PLGA nanoparticles based solution. In Carrier 2 group the diabetic wound was treated with EEP. In Treatment group animals received EEP-PLGA NPs on the wound. Wound size was measured on 7, 14 and 21 days after surgery. The expression of p53, bcl-2, Caspase III, were evaluated using reverse-transcription PCR and Immunohistochemical staining. The Treatment group had significantly reduced the wound size compared to other groups (P = 0.001). histological and morphometric studies, and mean rank of the qualitative studies demonstrated that there was significant difference between Treatment group and other groups (P < .05). Observations demonstrated that ethanolic extract of propolis-loaded PLGA nanoparticles significantly shortened the inflammatory phase and accelerated the cellular proliferation. Accordingly, the animals in Treatment group revealed significantly (P < .05) higher fibroblast distribution/one mm2 of wound area and rapid re epithelialization. The mRNA levels of bcl-2, p53 and caspase III were remarkably (P < .05) higher in Treatment group compared to control and animals. The immunohistochemical analyzes confirmed the RT-PCR findings. EEP-PLGA NPs offered potential advantages in wound healing acceleration and improvement through angiogenesis stimulation, fibroblast proliferation and granulation tissue formation in early days of healing phases, acceleration in diabetic wound repair associated with earlier wound contraction and stability of damaged area by rearrangement of granulation tissue and collagen fibers.
Keywords: PLGA nanoparticles; diabetic wound; propolis; rat.