Objective: To assess the effect of bromelain on different aspects of the wound healing process in type 1 diabetic rats. Method: In this study, 112 streptozocin-diabetic (type 1) male Wistar rats were euthanised; 28 each on days three, five, seven and 15, after a wound incision had been made. To estimate changes in a number of different cellular and tissue elements, histological sections were provided from all wound areas and stained with haematoxylin and eosin. Some 1.056mm2 of total wound area from all specimens were evaluated, by assessment of 4200 microscope photos provided from all histological sections, by stereological methods. A biomechanical test of each wound area was performed with an extensometer to evaluate the work-up to maximum force and maximum stress of the healed wound on day 15. Results: In the experimental groups, bromleain caused significant wound contraction and reduced granulation tissue formation by day 7 (p=0.003); increased neovasculars (new small vessels that appear in the wound area during wound healing) on days three, five and seven (p=0.001); significantly increased fibroblasts on day five but decreased by day seven (p=0.002); and significantly decreased macrophage numbers and epithelium thickness on all days of study (p=0.005). Wound strength significantly increased in experimental groups by day 15. Conclusion: Bromelain has a wide range of therapeutic benefits, but in most studies the mode of its action is not properly understood. It has been proved that bromelain has no major side effects, even after prolonged use. According to the results of this study, bromelain can be used as an effective health supplement to promote and accelerate wound healing indices, reduce inflammation and improve biomechanical parameters in diabetic wounds.

Objective: Many studies have revealed the prominent roles of mast cells in wound healing, including inflammatory reactions, angiogenesis and extracellular matrix reabsorption. In the present study, we aimed to assess the probable therapeutic features of bromelain on wound contraction and mast cell degranulation in wound healing in experimental diabetic animals. Method: Male rats were grouped as control, vehicle and experiment. Skin wounds were generated in all groups. Treatments were applied with distilled water and with bromelain (BR) intraperitoneally in the vehicle and experimental groups, respectively. Following skin wound generation, animals were euthanised on days 3, 5, 7 and 15. We gathered 16,800 microscopic images to count the mast cells and degranulation level (Image J software). The wound contraction index was assessed both microscopically (Image J software) and macroscopically (time-lapse photography). The meshwork evaluation method was used to assess wound healing. Results: Time-lapse photography revealed that the BR significantly (p<0.05) accelerated wound contraction and healing. BR significantly (p<0.05) increased the total number of mast cells in all experimental groups on days 5 and 7. The count of grade III (degranulated) mast cells was reduced significantly (p<0.05) on days 5 and 7 in experimental groups compared to control and vehicle groups. Conclusion: In this study, the rate of wound healing was accelerated considerably following BR administration. In addition, this agent decreased the count of degranulated mast cells, leading to wound contraction and healing.