Effects of different cellulose membranes regenerated from Styela clava tunics on wound healing.

The aim of this study was to investigate the therapeutic effects of three different cellulose membranes (CMs) manufactured from Styela clava tunics (SCTs) on the healing of cutaneous wounds. We examined the physical properties and therapeutic effects of three CMs regenerated from SCTs (referred to as SCT‑ CMs), including normal CM (SCT‑CM), freeze-dried SCT‑CM (FSCT‑CM) and sodium alginate-supplemented SCT‑CM (ASCT‑CM) on skin regeneration and angiogenesis using Sprague-Dawley (SD) rats. FSCT‑CM exhibited an outstanding interlayered structure, a high tensile strength (1.64 MPa), low elongation (28.59%) and a low water vapor transmission rate (WVTR) compared with the other SCT-CMs, although the fluid uptake rate was maintained at a medium level. In the SD rats with surgically wounded skin, the wound area and score of wound edge were lower in the FSCT‑CM-treated group than in the gauze (GZ)-treated group on days 3-6 and 12-14. In addition, a significant attenuation in the histopathological changes was observed in the FSCT‑CM-treated group. Furthermore, the expression level of collagen-1 and the signaling pathway of transforming growth factor (TGF)-β1 were significantly stimulated by the topical application of FSCT‑CM. However, no signs of toxicity were detected in the livers or kidneys of the three SCT‑CM-treated groups. Overall, our data indicate that the FSCT‑CM may accelerate the process of wound healing in the surgically wounded skin of SD rats through the regulation of angiogenesis and connective tissue formation without inducing any specific toxicity.