Topical administration of pullulan gel accelerates skin tissue regeneration by enhancing collagen synthesis and wound contraction in rats

Here, we have studied the efficacy of pullulan gel on wound healing by performing biochemical, biophysical and histological investigations. A 2 cm(2) open excision wound was made on the dorsum of the rats and topically treated with 500 mu l of pullulan gel. The control group was left untreated. The povidone-iodine (PI) ointment treated animals were considered as positive control. The granulation tissues formed were collected at different time point intervals and used for various biochemical, biophysical and histological analyses. Biochemical analyses revealed that pullulan gel significantly (p <0.001) improved the collagen, hexosamine, protein and DNA content. Biophysical analyses resulted in an increased rate of wound contraction (p < 0.001). The period of epithelialization was shorter (p < 0.001) in pullulan gel treated group (11 days) than control (22 days) and PI group (17 days). Histological evaluation on days 4, 8 and 11 substantiated that pullulan gel treatment improved the wound reepithelialization, dermal regeneration, blood vessels formation and collagen synthesis than in control and PI groups. Interrupted SDS-PAGE of collagen showed an increase in Type III collagen band evident for the healing potential of pullulan gel. Thus, our results strongly prove that pullulan gel could be a potential wound healing agent. (C) 2020 Elsevier B.V. All rights reserved.