Effect of Topical H1-antihistamine on the level of Transforming growth factor beta (TGF-β) and Collagen of Acute wound in animal model

Imbalance of collagen synthesis and degradation causes formation of abnormal scarring leading to hypertrophic scar or keloid. Previous studies have shown that applying antihistamines could reduce the level of dermal collagen. However, no data whether topical antihistamine could be used as preventative therapy for abnormal scar formation. The aim of this study was to assess whether the application of topical antihistamine in acute wounds could affect the level of transforming growth factor beta (TGF-β), a regulator of wound healing process, and collagen in wound healing phase in order to suppress the keloid formation. A randomized post-test only control group design study was conducted. Twenty-four acute wounds on Rattus novergicus rats were randomized divided into control and treatment groups. The animals of treatment group received daily topical antihistamine consisting 1% diphenhydramine hydrochloride and 0.1% zinc acetate. The full-thickness skin tissue from each rat were taken on day 5 and 21 and were subjected to ELISA test to measure the levels of TGF-β and collagen. Our data found that in the treatment group, the level of collagen decreased significantly over time (1623.61ng/mL on day 5 to 755.15ng/mL on day 21, p=0.001). Similarly, the level of TGF-β also decreased although was not statistically significant (p=0.766). In contrast, the levels of TGF-β level and collagen in the control group increased significantly from day 5 to day 21, p=0.003 and p=0.001, respectively. The level of TGF-β in treatment group was significantly higher compared to the control group p=0.001 on day 21 while the level of collagen had no different between treatment and control group (p=0.124). In conclusion, our data suggest that topical antihistamine reduced the levels of TGF-β and collagen at the end of the proliferation phase or the beginning of the remodeling phase. Further study is warrant to elucidate the effect of antihistamine on other would healing markers or parameters.