Radix Salvia miltiorrhiza Ameliorates Burn Injuries by Reducing Inflammation and Promoting Wound Healing

Purpose: Radix Salvia miltiorrhiza (RSM), a commonly used medicinal plant, has been reported to have anti-inflammatory effects, but relevant studies on burn injuries are lacking. We investigated the anti-inflammation and wound healing (WH) effects of an aqueous extract of RSM on a burn model in rats.Methods: The effects of RSM were studied by heat-induced burns in rats, treatment with vehicle, Jinwanhong ointment, and RSM (1.5 or 0.75 g/mL). Indicators of burn tissue (BT) were photographed by digital machines and analyzed. The microcirculation in BT was detected by scattered full-frame real-time imaging. Levels of inflammatory mediators and growth factors were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining. Local pathologic changes in BT were observed by hematoxylin-and-eosin (HE) staining. Ultrahigh pressure liquid chromatography-linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap-MS) was used to explore the absorption of RSM in local skin, subcutaneous tissue, muscle tissue, serum, liver tissue, and kidney tissue.Results: RSM treatment could reduce the wound area, increase percent WH, increase blood perfusion in BT, reduce serum levels of interleukin (IL)-6, IL-1, tumor necrosis factor-alpha (TNF-alpha), increase levels of epidermal growth factor (EGF), transforming growth factor (TGF)-I3, and hydroxyproline (Hyp) in serum, and increase protein expression of basic fibroblast growth factor (bFGF), TGF-I31, EGF, and insulin-like growth factor-1 (IGF)-1 in skin tissues. RSM treatment led to micro-absorption in the skin, subcutaneous tissues, and muscle, but not in the blood, liver, or kidney.Conclusion: RSM may promote WH by exerting anti-inflammatory effects, improving local-wound microcirculation, and accelerating the metabolism at the wound surface.