Topical fish oil accelerates wound healing in rats with type 2 diabetes mellitus

To observe the effect of topical fish oil on wound healing in rats with type 2 diabetes mellitus (T2DM) and to investigate its mechanism of action.

The T2DM rat model was established on 57 SD rats with a high-fat, high-sugar diet combined with intraperitoneal injection of STZ, and finally, T2DM model was established successfully in 49 rats. Then wound model was inflicted surgically, and the rats were divided into fish oil group (n=17), corn oil group (n=16) and model control group (n=16). Topical medication was applied to each group on the next day after wound modelling. During the intervention period, the wound healing was observed in all rats of each group. After the wound tissue samples were collected on 7 and 14 d after wound modelling, the levels of oxidative stress indexes (MDA, SOD and CAT) and inflammatory factors (TNF-α, IL-1β, IL-6 and IL-10) were detected, and pathological changes and collagen fibril deposition in the dermis were observed with HE and Masson staining. The expression of SIRT1, Nrf2 and NQO1 was measured with Western blotting.

Compared with the corn oil group and the model control group, the fish oil group had significantly improved wound healing rate on 7 and 14 d after modelling (P<0.05), increased collagen fibril deposition, decreased levels of MDA, TNF-α, IL-1β and IL-6 in wound tissue (P<0.05), while increased SOD, CAT and IL-10 levels (P<0.05), and protein levels of SIRT1, Nrf2 and NQO1 in the wound tissue (P<0.05). There were no statistical differences in above indicators between the corn oil group and the model control group (P<0.05).

Topical application of fish oil can effectively promote wound healing in T2DM rats, and the mechanism may be related to its reduction of oxidative stress and inflammation of wound.