Histological analysis of rat cutaneous wounds treated with a semi-solid formulation of linseed (Linum usitatissimum L.) oil

The oil linseed of Linum usitatissimum L. (Linaceae) is popularly known as linen. Its chemical composition shows the presence polyunsaturated fatty acids, linolenic (56.6%) and linoleic acid (13.2%), and the monounsaturated fatty acid oleic (17.8%) which are important for the maintenance of normal dermal structure [1, 2]. The purpose of this study was to investigate the effects of a a semi-solid formulation of linseed oil – SSFLO (1%, 5% or 10%) on re-epithelialization of excision wound model. Surgically standardized circular (±78.5mm²) wounds were made on the dorsum of Wistar rat. The animals were divided into five groups (n=6) and treated for 14 days with SSFLO (1%, 5% or 10%), petrolatum jelly (negative control) or commercial emulsion of sunflower oil (positive control). At 14th days the animals were euthanized and the scar tissue was collected for histological and histomorphometric analysis to evaluate re-epithelization, quantification of inflammatory cells, fibroblast cells, blood vessels and collagen density. All animals treated with SSFLO (1% or 5%) or commercial emulsion of sunflower oil (positive control) showed complete re-epithelialisation, against only 33.33% showed by negative control group. In the morphometric evaluation a significant increase (p<0.05) in the number of inflammatory cells in the group treated with 10% SSFLO was observed compared to the ESO control group. Among the remaining variables, there were no significant differences observed. The results clearly demonstrate that locally administered 1% and 5% SSFLO promote a significant re-epithelization during the healing process, and might represent a novel therapeutic approach in cutaneous wounds.

Keywords: Linum usitatissimum, re-epithelialization, cutaneous wounds

References: [1] Joshi K et al. (2006) PLEFA 74:17–21.

[2] Otranto M et al. (2010) WRR 18: 629–636.