In vivo wound-healing and antioxidant activity of aqueous extract of Roylea elegans leaves against physically induced burn model in Wistar albino rats

Roylea elegans Wall. ex Benth. is a lemon-scented hoary shrub belonging to the mint family (Lamiaceae). Traditionally, a local tribe of the Himalayan region uses leaves for scabs and skin infections. The aerial parts and leaves are widely used to cure various skin ailments. The plant is well known for two furanoid diterpenes, royeleganin and royelegafuran. The aqueous extract of Roylea elegans (AERE) leaves was investigated for wound-healing effects in rats using a physically induced burn model by assessing different parameters. Animals were divided into four groups (six rats in each group). Group I animals were considered as disease control and topically given base cream. Group II was considered as standard control and treated topically with Framycetin sulphate cream (1% w/w). Group III and IV animals were treated topically with creams containing 5 or 10% of AERE, respectively. Several parameters such as wound contraction rate, epithelialization period, and enzymatic and non-enzymatic antioxidant markers along with pro- and anti-inflammatory cytokines were studied followed by histopathological studies. The animals treated with AERE cream exhibited significant declination in the wound area and increased collagen content as compared to the disease control group. The results showed that the lower dose (5%) of AERE produced a significant decrease in the epithelialization period, wound contraction rate, and collagen content. Increased levels of cytokine production may be one of the mechanisms in accelerating the wound-healing process. The study established the traditional claim as an antioxidant and wound-healing potential of Roylea elegans by promoting the accelerated wound-healing activity against the physically induced burn model.