Effects of Rhodiola imbricata on Dermal Wound Healing

Abstract

Rhodiola imbricata (Crassulaceae) is a perennial herb growing at high-altitude (4000 - 5000 m) in the western Himalayas. The present study was aimed at investigating the healing efficacy of R. imbricata rhizome ethanol extract using a rat excision wound model. The extract was found to be rich in polyphenols. The extract treated wounds were found to heal much faster as indicated by the improved rate of wound contraction and decreased time taken for epithelialization (11.33 vs. 18.33 days in the untreated group). The extract treatment increased cellular proliferation and collagen synthesis at the wound site, as evidenced by the increases in DNA, protein, hydroxyproline and hexosamine contents in comparison to a positive control treated with povidone-iodine ointment. These results were also supported by histological examinations. Furthermore, the treatment also caused an increase in antioxidant and a decrease in lipid peroxide levels in the granulation tissue. The results suggest that R. imbricata rhizome ethanol extract possesses a significant wound healing activity.

Abbreviations

DNA: deoxyribonucleic acid

FCR: Folin-Ciocalteu reagent

GSH: glutathione reduced

IL-6: interleukin-6

LPO: lipid peroxide

TNF-α: tumor necrosis factor-α

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