Bioactive electrospun nanoyarn-constructed textile dressing patches delivering Chinese herbal compound for accelerated diabetic wound healing

The treatment of tenacious diabetic wounds still remains an enormous challenge in clinics, originated from the complicated pathological microenvironment of wound sites. Therefore, it's urgently required to develop one type of innovative dressing patch with appropriate microstructure and multifunctions to regulate the pathological microenvironment and promote the regeneration of diabetic wounds. In this study, novel gelatin (Gel)/poly (L-lactic acid) (PLLA) nanofibrous yarns loading with or without Salvia miltiorrhiza Bunge-Radix Puerariae herbal compound (SRHC) are fabricated by using our modified electrospinning strategy, which are further interlaced into nanofibrous woven fabrics respectively, serving as biofunctional dressing patches for potential diabetic wound treatment application. The actual photographs and SEM images confirm that all the different nanofibrous textiles with or without SRHC exhibited a uniform interwoven structure of warp and weft, and the internal nanofibers present bead-free morphology and uniaxially oriented structure along the longitudinal axis of nanofibrous yarns. Moreover, all the different nanofibrous woven fabrics are demonstrated to possess strong mechanical properties and great surface wettability. The in vitro cell characterization shows that the addition of SRHC can significantly promote the attachment and proliferation of human dermal fibroblasts (HDFs), and also dramatically inhibit the secretion levels of proinflammatory factors of M1 macrophages. The in vivo diabetic mouse full-thickness skin model experiments reveal that the as-developed SRHC-loaded Gel/PLLA nanofibrous textile shows the best performances referring to short wound healing time (100 % wound closure after 18 days of treatment) and high-quality regeneration (i.e., enhance collagen deposition, improve re-epithelialization and neovascularization, and increase hair follicles), which assuredly finds great interests serving as an innovative dressing patch for the treatment of hard-to-heal diabetic wounds.