Tert-butylhydroquinone promotes skin flap survival by inhibiting oxidative stress mediated by the Nrf2/HO-1 signalling pathway

Background and Purpose: Skin flaps are among the most important means of wound repair in clinical settings. However, partial or even total distal necrosis may occur after a flap operation, with severe consequences for both patients and doctors. This study investigated whether tert-butylhydroquinone (TBHQ), a known agonist of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), and an antioxidant, could promote skin flap survival. Experimental Approach: McFarlane skin flap models were established in male Sprague-Dawley rats and then randomly divided into control, low-dose TBHQ, and high-dose TBHQ treatment groups. On postoperative day 7, the survival and blood flow of the skin flaps were assessed. Using flap tissue samples, angiogenesis, inflammation, apoptosis, autophagy, and Nrf2/haem oxygenase 1 (HO-1) signalling pathway activity were measured with immunohistochemical techniques and western blotting. Key Results: TBHQ dose-dependently stimulated the Nrf2/HO-1 signalling pathway, inducing autophagy through the up-regulation of LC3B and beclin 1 and concurrently suppressing p62 expression. Additionally, TBHQ hindered apoptosis by enhancing Bcl-2 expression while inhibiting the expression of Bax. It suppressed inflammation by inhibiting the expression of interleukin 1 beta, interleukin 6, and tumour necrosis factor-alpha and enhanced angiogenesis by promoting the expression of vascular endothelial growth factor. Conclusion and Implications: In summary, TBHQ promoted flap survival in rats by up-regulating the Nrf2/HO-1 signalling pathway. As TBHQ is already widely used as a food additive, it could offer an acceptable means of improving clinical outcomes following skin flap surgery in patients.