Influence of topical administration of n‐3 and n‐6 essential and n‐9 nonessential fatty acids on the healing of cutaneous wounds

TLDR

In skin injury, an inflammatory response followed by tissue formation occurs, and poly‑ and monounsaturated fatty acids modulate these inflammatory processes. The study examined whether topical linolenic (n‑3), linoleic (n‑6), and oleic (n‑9) fatty acids influence the healing of surgically induced skin wounds. Oleic acid (n‑9) accelerated wound closure and suppressed nitric‑oxide production, linoleic acid (n‑6) modestly improved closure with a transient nitric‑oxide peak, whereas linolenic acid (n‑3) delayed healing, induced an early nitric‑oxide surge and later extracellular‑matrix deposition, indicating fatty acids have distinct therapeutic potentials for cutaneous repair.

Abstract

Injury triggers a series of physiological events at the wound site. These include an inflammatory response that is established shortly after the injury, which is then followed by an intense formation of tissue over a period of days. Poly‐ and monounsaturated fatty acids exert major functions on the inflammatory responses, either in the form of phospholipids anchored in the cell membrane or as soluble lipoic mediators. We present evidence that linolenic (n‐3), linoleic (n‐6), and oleic (n‐9) fatty acids can modulate the closure of surgically induced skin wounds. We found that n‐9 fatty acids induced faster wound closure when compared to n‐3, n‐6, and control. In addition, n‐9 fatty acids strongly inhibited the production of nitric oxide at the wound site. A mild improvement on wound closure was observed in the n‐6 fatty acid‐treated animals concurrent with a peak in nitric oxide production at 48 hours postsurgery. N‐3 fatty acid treatment significantly delayed wound closure. Furthermore, we showed that n‐3 fatty acid induced a peak in nitric oxide at 3 hours postsurgery and an intense deposition of extracellular matrix after 5 days of treatment. Thus, our results suggest a relevant role and potential therapeutic implication for fatty acids on skin wound healing.