生物3D打印丹酚酸B-海藻酸钠-明胶皮肤支架促进糖尿病大鼠创面愈合OA北大核心CSTPCD

Objective:To investigate the therapeutic effect of 3D bioprinted salvianolic acid B(SAB)-sodium alginate-gelatin skin scaffold on diabetic rat wounds.Methods:The 0％,0.5％,1.0％and 1.5％of bioinks were prepared according to the percentage of SAB in the total weight of sodium alginate and gelatin.Skin scaffolds with different types were produced by biological 3D printing technology.The microstructure was observed by scanning electron microscopy,and the concentration of SAB in vitro was determined by high-performance liquid chromatography.Skin scaffolds were used to treat wounds in type 2 diabetic rats that were divided into the control group,the vaseline gauze group,and the skin scaffold groups(0％SAB,0.5％SAB,1.0％SAB,1.5％SAB groups).The healing and exudation of the wounds were observed on day 7 and 14.Meanwhile,the wound tissues wete taken for HE and Masson staining,as well as for reactive oxygen species(ROS)detection,and the levels of superoxide dismutase(SOD),glutathione peroxidase(GSH-PX),catalase(CAT)and malondialdehyde(MDA)were detected.Results:Skin scaffolds in the four groups showed a mesh-like 3D structure with uniform pore distribution.The cumulative release of SAB increased gradually over time.General observations showed that wounds healed well in each group and healed better in 1.0％SAB group than in other groups.On day 7,ROS Levels were lower in the 1.0％SAB group than in other groups(P＜0.05).On day 14,ROS levels were lower in the 1.0％SAB group than in all groups except the 1.5％SAB group(P＜0.01),and there was no significant difference in ROS levels between the 1.0％SAB group and the 1.5％SAB group(P=0.136).On day 7,the levels of SOD,GSH-PX and CAT were higher in the 1.0％SAB group than in other groups(P＜0.05),MDA level was lower in the 1.0％SAB group than in the control group,vaseline gauze group and 0％SAB group(P＜0.05).On day 14,the levels of SOD,GSH-PX and CAT were higher in the 1.0％SAB group than in the control group,vasolin gauze group and the 0％SAB group(P＜0.05),MDA level was lower in the 1.0％SAB group than in the control group and vaseline gauze group(P＜0.05).HE staining showed that the wounds were well repaired in each group and more new tissues were formed in the 1.0％SAB group than in other groups.Masson staining showed that on day 7 and 14,collagen deposition in the 0.5％,1.0％,1.5％SAB groups was more than that in other groups(P＜0.05).Conclusion:The 1.0％SAB-sodium alginate-gelatin skin scaffold on the day 7 and 14 may not only inhibits the generation of ROS and upregulates the expression of various antioxidant enzymes,thereby inhibiting oxidative stress response in wound tissues,but also promotes collagen deposition,ultimately enhancing wound healing in diabetic rat.