Efficacy of Topical Folic Acid in the Healing of Deep Second-Degree Burn Wound via Redox Modulation in Rat.

Folic acid, synthetic form of folate, is necessary for synthesis and for repair of DNA. Studies have shown that folic acid enhances the DNA repair capacity of skin fibroblasts following tissue damage. The research objective was to assess the efficacy of topical folic acid on the treatment of second-degree burn wound in a rat model. The second-degree burn wounds were induced on the dorsal skin of Wistar rats. Animals were randomly placed into five groups (n = 5) as follows: (1) non-treatment group, (2) cream base treated group, (3) silver sulfadiazine (SSD) 1% treated group, (4) folic acid 1% cream treated group, and (5) folic acid 4% cream treated group. The healing effects of folic acid were assessed by monitoring the wound contraction rate, measuring the tissue content of hydroxyproline, and conducting a microscopical study of wound healing in experimental groups. For evaluation of antioxidant properties of folic acid, the total antioxidant capacity (TAC) and the amount of reactive oxygen species (ROS) in tissue samples were measured. Our results revealed that topical folic acid 1% and 4% (w/w) significantly (p < 0.05) accelerated wound contraction and re-epithelialization rates, enhanced hydroxyproline content of tissue, and decreased the median time to complete wound closure compared to non-treatment and cream base treated groups. Furthermore, 1% and 4% folic acid creams significantly (p < 0.05) increased the TAC content of skin tissue and suppressed the ROS levels compared to non-treatment and cream base groups. In conclusion, folic acid is capable of accelerating the burn wound healing process possibly via modulating oxidative stress.