Adenosine A2A receptor agonists promote more rapid wound healing than recombinant human platelet-derived growth factor (becaplermin gel)

Animal studies of the topical application of adenosine A(2A) receptor agonists show that it promotes wound closure. To further confirm the efficacy of adenosine A(2A) receptor agonists as promoters of wound healing, we compared the effect of MRE0094, a novel selective adenosine A(2A) receptor agonist, to CGS-21680, a reference selective adenosine A(2A) receptor agonist, as well as to recombinant human platelet-derived growth factor (0.01% Becaplermin gel), an agent currently used to promote healing of diabetic ulcers, on wound closure in healthy BALB/C mice. Wounds (similar to12 mm diameter) were created on the dorsum of mice (two per mouse) and then treated daily with vehicle, 0.01% Becaplermin gel, or different doses of the adenosine A(2A) receptor agonists. The wound margins were traced onto plastic sheets, and the wound areas were digitized, quantitated, and compared. We found that application of MRE0094 (1 mug/wound and 10 A mug/wound) and CGS-21680 (1 mug/wound and 5 mug/wound) achieved 50% wound closure significantly more rapidly than control application (day 1.9, 1.9, 3.5, 3.2, respectively, versus control day 4, p < 0.05 ANOVA). Surprisingly, neither higher nor lower concentrations of CGS-21680 affected the rate of wound closure, as compared to control. In contrast, Becaplermin gel did not increase the rate at which wounds closed (50% closure by day 7.2, p = NS versus control). These data confirm our prior observations that adenosine A(2A) receptor agonists promote wound closure, and they suggest that these agents may be as effective if not more effective than Becaplermin gel for the treatment of poorly healing wounds.