Locationally activated PRP via an injectable dual-network hydrogel for endometrial regeneration

Enhancing the effectiveness of platelet-rich plasma (PRP) for endometrial regeneration is challenging, due to its limited mechanical properties and burst release of growth factors. Here, we proposed an injectable interpenetrating dual-network hydrogel that can locationally activate PRP within the uterine cavity, sustained release growth factors and further address the insufficient therapeutic efficacy. Locational activation of PRP is achieved using the dual-network hydrogel. The phenylboronic acid (PBA) modified methacrylated hyaluronic acid (HAMA) dispersion chelates Ca²⁺ by carboxy groups and polyphenol groups, and in situ crosslinked with PRP-loaded polyvinyl alcohol (PVA) dispersion by dynamic borate ester bonds thus establishing the soft hydrogel. Subsequently, in situ photo-crosslinking technology is employed to enhance the mechanical performance of hydrogels by initiating free radical polymerization of carbon-carbon double bonds to form a dense network. The PRP-hydrogel significantly promoted the endometrial cell proliferation, exhibited strong pro-angiogenic effects, and down-regulated the expression of collagen deposition genes by inhibiting the TGF-β1-SMAD2/3 pathway in vitro. In vivo experiments using a rat intrauterine adhesion (IUA) model showed that the PRP-hydrogel significantly promoted endometrial regeneration and restored uterine functionality. Furthermore, rats treated with the PRP-hydrogel displayed an increase in the number of embryos, litter size, and birth rate, which was similar to normal rats. Overall, this injectable interpenetrating dual-network hydrogel, capable of locational activation of PRP, suggests a new therapeutic approach for endometrial repair.