Selenium-loaded cellulose film derived from Styela clava tunic accelerates the healing process of cutaneous wounds in streptozotocin-induced diabetic Sprague-Dawley rats.

PURPOSE: Aims of this study is to evaluate the therapeutic effects and toxicity of Se-loaded cellulose film originated from Styela clava tunic (SeSCTF) on cutaneous wounds during diabetic conditions. MATERIALS AND METHODS: Alterations in skin regeneration, angiogenesis and toxicity were examined using streptozotocine (STZ)-induced diabetic Sprague Dawley® (SD) rats with surgical skin wounds after application of SeSCTF for 12 days. RESULTS: SCTF showed high tensile strength (1.64 MPa), low elongation (28.59%), low water vapor transmission rate (WVTR) and outstanding porous structure. Although SeSCTF application did not induce any significant alterations in glucose concentration or toxicity, wound morphology was rapidly recovered in the SeSCTF treated group relative to the gauze (GZ) and SCTF treated group. Moreover, recovery of re-epithelization, wound contraction and number of blood vessel was observed in SeSCTF treated groups when compared with all other groups. Furthermore, the SeSCTF treated group showed complete recovery of key protein expressions of the downstream signaling pathway of vascular endothelial growth factor (VEGF), angiopoietin-2/1 (Ang-2/1), the signaling pathway of insulin receptors and anti-oxidative status. CONCLUSIONS: Overall, the results of this study suggest that SeSCTF accelerates the healing process of cutaneous wounds in STZ-induced diabetic SD rats through stimulation of angiogenesis and the glucose receptor signaling pathway.

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 (SCT­CM), freeze-dried SCT­CM (FSCT­CM) and sodium alginate-supplemented SCT­CM (ASCT­CM) on skin regeneration and angiogenesis using Sprague-Dawley (SD) rats. FSCT­CM 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 FSCT­CM-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 FSCT­CM-treated group. Furthermore, the expression level of collagen-1 and the signaling pathway of transforming growth factor (TGF)-ß1 were significantly stimulated by the topical application of FSCT­CM. However, no signs of toxicity were detected in the livers or kidneys of the three SCT­CM-treated groups. Overall, our data indicate that the FSCT­CM 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.

Bacterial cellulose membrane produced by Acetobacter sp. A10 for burn wound dressing applications.

Bacteria cellulose membranes (BCM) are used for wound dressings, bone grafts, tissue engineering, artificial vessels, and dental implants because of their high tensile strength, crystallinity and water holding ability. In this study, the effects of BCM application for 15 days on healing of burn wounds were investigated based on evaluation of skin regeneration and angiogenesis in burn injury skin of Sprague-Dawley (SD) rats. BCM showed a randomly organized fibrils network, 12.13 MPa tensile strength, 12.53% strain, 17.63% crystallinity, 90.2% gel fraction and 112.14 g × m(2)/h highest water vapor transmission rate (WVTR) although their swelling ratio was enhanced to 350% within 24h. In SD rats with burned skin, the skin severity score was lower in the BCM treated group than the gauze (GZ) group at all time points, while the epidermis and dermis thickness and number of blood vessels was greater in the BCM treated group. Furthermore, a significant decrease in the number of infiltrated mast cells and in vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) expression was observed in the BCM treated group at day 10 and 15. Moreover, a significant high level in collagen expression was observed in the BCM treated group at day 5 compared with GZ treated group, while low level was detected in the same group at day 10 and 15. However, the level of metabolic enzymes representing liver and kidney toxicity in the serum of BCM treated rats was maintained at levels consistent with GZ treated rats. Overall, BCM may accelerate the process of wound healing in burn injury skin of SD rats through regulation of angiogenesis and connective tissue formation as well as not induce any specific toxicity against the liver and kidney.