Ameliorating effects of stevia extract combined with green-synthesized silver nanoparticles coated with soy soluble polysaccharide on diabetic wounds in the rat model

Abstract

The use of silver nanoparticles (AgNPs) as a new treatment for diabetic wound (DW) healing is limited due to cytotoxicity. This study evaluated the potential of a green approach using Stevia extract (SE) to synthesize AgNPs coated with Soy Soluble Polysaccharides (SSPS-gAgNPs) to accelerate the wound healing treatment. The SSPS-gAgNPs were characterized by TEM, XRD, DLS, and FTIR techniques. The cytotoxic effect was evaluated using the MTT assay. The effect of SSPS-gAgNPs and SE on in vivo DW healing and MMP9, TIMP-1and bFGF mRNA expression was evaluated. In day 14 post wounding, wound area (mm) was decreased in presence of alone SSPS-gAgNPs (65.93±4.39; P=0.000) or SE (73.31±8.56; P=0.000) alone or a of combination SSPS-gAgNPs / SE (45.93±8.14; P=0.000) in compassion with untreated control (107±8.72). In addition, collagen deposition percentage was significantly higher in SSPS-gAgNPs/ SE combination (%47.05± 3.070) than alone SSPS-gAgNPs (%36.55± 3.20; P˂0.01) or SE (%21.47±2.74; P˂0.0001). While, the lymphocyte number per area (mm2) was decreased in response to SSPS-gAgNPs/ SE combination (78.33±9.50) compared with alone SSPS-gAgNPs SE combination (143.3±11.72; P˂0.01). A combination of SSPS-gAgNPs/ SE has shown greater effect on increasing the expression of b-FGF and TIMP-1 expression and reducing MMP9 expression than alone SSPS-gAgNPs or SE. Taken together, the findings reveal that SSPS-gAgNPs combined with SE have considerable ability to accelerate healing of the DW. Therefore, this combination may be an alternative therapy to improve the outcomes of DW.