Celosia argentea Linn. leaf extract improves wound healing in a rat burn wound model

Celosia argentea (CA) is used in traditional medicine for sores, ulcers, and skin eruptions. The present study was aimed at investigating the healing efficacy of CA extract in an ointment formulated (10 % w/w) as an alcohol extract of CA using a rat burn wound model. Wound closure occurred earlier in the treated rats (15 days vs. 30 in the untreated group; p < 0.05). Granulation tissue collected on every fifth day of healing showed an increase in collagen and hexosamine content at a faster rate in the treated wounds. This correlated with the accelerated wound closure observed in the treated groups. To probe the cellular basis of this effect, we investigated the effect of this extract on two major cellular responses; cell proliferation and cell motility, in two key cell lineages, fibroblasts and keratinocytes. CA was not toxic at concentrations of < 3 microg/ml in fibroblasts and < 30 microg/ml in keratinocytes. The alcohol extract promoted cell motility and proliferation of primary dermal fibroblasts at 0.1-1.0 microg/ml but did not alter these responses in primary keratinocytes. In an initial examination of molecular mechanisms, we found that the CA extract did not alter fibroblast and keratinocyte responses to the wound repair-associated epidermal growth factor receptor ligands. In short, we demonstrate a salutary action of the CA extract on wound healing, and suggest that this may be due to mitogenic and motogenic promotion of dermal fibroblasts.