Red and blue LED light increases the survival rate of random skin flaps in rats after MRSA infection.

Abstract

Skin flap transplantation is a conventional wound repair method in plastic and reconstructive surgery, but infection and ischemia are common complications. Photobiomodulation (PBM) therapy has shown promise for various medical problems, including wound repair processes, due to its capability to accelerate angiogenesis and relieve inflammation. This study investigated the effect of red and blue light on the survival of random skin flaps in methicillin-resistant Staphylococcus aureus (MRSA)-infected Sprague Dawley (SD) rats. Forty male SD rats were divided into control and light-emitting diode-red and blue light-treated (LED-RBL) groups at a ratio of 1:1 and a McFarland flap procedure was performed, which was subsequently infected with MRSA strains. After 7 days, the appearance and survival of the flaps were evaluated. The microvascular density was determined by hematoxylin and eosin (HE) staining. The expression levels of vascular endothelial growth factor (VEGF), hypoxia inducible factor 1α (HIF-1α), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (normally expressed as AKT) were detected by immunohistochemistry. The flap survival rate and microvascular density in the LED-RBL group were significantly higher than those in the control group (P < 0.05). In addition, the VEGF, HIF1-α, PI3K, and AKT levels were significantly higher in the LED-RBL group compared to the control group (P < 0.05). Red and blue light increased the survival area of the infected flap in rats by promoting angiogenesis, relieving oxidative stress, and reducing bacterial loads, indicating that PBM therapy is a convenient, simple, analgesic, and safe treatment intervention in promoting the survival rate of transplanted flaps after wound repair surgery.