Wound healing in diabetic mice with soluble microneedle-loaded platelet-rich plasma lysate: a preliminary study / 中国输血杂志

ABSTRACT

【Objective】 To prepare microneedles(MNs) loaded with platelet-rich plasma lysate (PL) using Carboxymethyl chitosan (CMCS), and explore the prospect of PL MNs in the treatment of diabetic wounds. 【Methods】 CMCS was used as the basic material, and an appropriate amount of polyvinylpyrrolidone (PVPK-60) was added to prepare needle materials of different concentrations, and the optimal concentration was determined by investigating the needle formation rate, morphological characteristics and mechanical properties, and the growth factor activity in PL MNs was investigated. The diabetic mice were randomly divided into four groups after the back wound was made, the control group did not do any treatment, the PL smear group was treated with PL smearing, the blank MNs group was treated with MNs without PL, and the PL MNs group was treated with PL microneedles. The effect of PL MNs in wound healing in diabetic mice was evaluated through body observation, H&E staining and immunohistochemistry results. 【Results】 When PVPK60 was 40 mg/mL, the needle formation rate was 100%, the array was complete, the needle body was full, and the needle was sharp. According to the results of mechanical-displacement curve and weight pressure change experiment, the prepared PL MNs have good mechanical strength. The results of growth factor analysis indicated that the content of vascular endothelial growth factor (VEGF) in PL was (625±35) pg/mL, and the content of platelet-derived growth factor-BB (PDGF-BB) was (18 741±1 287) pg/mL. After making the MNs, the VEGF content was (183±2) pg/mL, and the PDGF-BB content was (8049±1157) pg/mL. Although the concentration of growth factors decreased, growth factor activity was still preserved.The results of wound healing experiments in diabetic mice showed that the PL MNs group had better healing, and the wound healing rate was different from that of three groups (P<0.01). The results of H&E staining showed that the PL MNs group had fewer inflammatory cell infiltrates and bleeding spots. The number of fibroblasts and new microvascular in the control group was worse than that in the PL MNs group and the PL smear group. The results of immunohistochemistry indicated that the expression of pro-inflammatory factor IL-6 decreased, while anti-inflammatory factor TGF-β and angiogenesis index CD31 increased in the PL MNs group, which were significantly different from those in the other three groups (P<0.01). 【Conclusion】 The PL MNs prepared in this experiment have good mechanical properties, which has a positive effect on the wound healing of diabetic mice, and provides a new idea for diabetic wound healing.