Microenvironment-responsive, multimodulated herbal polysaccharide hydrogel for diabetic foot ulcer healing

Diabetic ulcers (DUs) usually suffer from severe infections, persistent inflammation, and excessive oxidative stress during the healing process, which led to the microenvironmental alternation and severely impede DU healing, resulting in a delayed wound healing. Therefore, it is particularly important to develop a medical dressing that can address these problems simultaneously. To this end, self-healing composite hydrogels were prepared in this study utilizing Bletilla striata polysaccharide (BSP) and Berberine (BER) with borax via borate ester bond. The chemical and mechanical properties of the BSP/BER hydrogels were characterized, and their wound healing performance was investigated in vivo and in vitro. The results showed that the BSP/BER hydrogel significantly accelerated wound healing in DU mice with the healing rate of 94.90 ± 1.81% on the 14th day by using BSP/BER5, and this outstanding performance was achieved by the multi-targeted biological functions of antibacterial, anti-inflammatory and antioxidant, which provided favorable microenvironment for orderly recovery of the wound. Aside from exhibiting the antibacterial rate of over 90% against both Escherichia coli and Staphylococcus aureus, the BSP/BER5 hydrogel could significantly reduce NO levels 4.544 ± 0.32 µmol/L to exert its anti-inflammatory effects. Additionally, it demonstrated a hemolysis rate and promotes cell migration capabilities at (34.92 ± 1.66%). With the above features, the developed BSP/BER hydrogel in this study could be the potential dressing for clinical treatment of DU wound.