Macromolecular carrier with long retention and body-temperature triggered nitric oxide release for corneal alkali burn therapy via leptin-related signaling

Bioinspired Wet Adhesive Proanthocyanidins Microneedles for Ocular Wound Healing

Microneedles have shown considerable potential in treating ocular diseases, yet enhancing their architecture and functionality to improve therapeutic efficacy poses marked challenges. Here, inspired by the antioxidant strategy of blueberries and the wet adhesive mechanism of clingfish, we construct hierarchical and multifunctional microneedles. These microneedles possess both wet adhesive and antioxidant properties, making them highly effective for ocular wound healing. Constructed using polyacrylic acid-N-hydroxysuccinimide-based hydrogel with hexagonal structures, these generated microneedles ensure strong adhesion in wet environments. Furthermore, by incorporating proanthocyanidins (pAc) into the tips, the microneedle is imparted with excellent competence to scavenge reactive oxygen species (ROS). In the rat model of ocular alkali burns, the designed microneedle not only exhibited robust adhesion and desirable antioxidant properties in the moist ocular environment but also facilitated sustained drug release and effective treatment. These results suggest that our bioinspired microneedles with multifunctional properties offer substantial advancement over conventional approaches, positioning them as promising candidates for versatile wound healing applications.

ROS-responsive & scavenging NO nanomedicine for vascular diseases treatment by inhibiting endoplasmic reticulum stress and improving NO bioavailability

Vascular diseases seriously threaten human life and health. Exogenous delivery of nitric oxide (NO) represents an effective approach for maintaining vascular homeostasis during pathological events. However, the overproduction of reactive oxygen species (ROS) at vascular injury sites would react with NO to produce damaging peroxynitrite (ONOO-) species and limit the therapeutic effect of NO. Hence, we design a ROS-responsive NO nanomedicine (t-PBA&NO NP) with ROS scavenging ability to solve the dilemma of NO-based therapy. t-PBA&NO NP targets NO and anti-oxidant ethyl caffeate (ECA) to the injury sites via collagen IV homing peptide. The ROS-triggered ROS depletion and ECA release potently alleviate local oxidative stress via ROS scavenging, endoplasmic reticulum and mitochondrial regulation. It subsequently maximizes vascular modulation effects of NO, without production of harmful compounds, reactive nitrogen species (RNS). Therefore, it significantly increases competitiveness of human umbilical vein endothelial cells (HUVECs) over human aortic smooth muscle cells (HASMCs) both in vitro and in vivo. The strategy proved effective in inducing faster re-endothelialization, inhibiting neointimal formation and restoring vascular homeostasis. The synergy between ROS depletion and NO therapy served as a new inspiration for the treatment of cardiovascular diseases and other ROS-associated illnesses.