Background: Frostbite injury creates an ischemic, hypoxic, and acidic microenvironment that often triggers severe oxidative stress and inflammation. Current therapeutic approaches are limited by low drug delivery efficiency and an inability to adequately regulate multiple pathological pathways. Although oxyresveratrol (OR) exhibits excellent antioxidant and anti-inflammatory activities, its application is hampered by poor aqueous solubility and low stability. Methods: We constructed Oxyresveratrol@Zeolitic Imidazolate Framework-8 nanoparticles (OR@ZIF-8) and further embedded them in a sodium hyaluronate (HA) matrix to form an OR@ZIF-8@HA composite hydrogel. The physicochemical properties and pH-responsive drug release behavior of the system were characterized. Its antioxidant activity, ability to promote cell migration, and capacity to modulate macrophage polarization were evaluated in cellular assays. The therapeutic efficacy was further investigated using a mouse frostbite model, with wound repair analyzed via histological staining. Results: The OR@ZIF-8 nanoparticles achieved a cumulative release rate of 75.46 ± 3.68% under acidic conditions within 36 h. In vitro experiments demonstrated that the formulation significantly scavenged TNF-α and IL-6, by 161.85 ± 19.43% and 125.37 ± 12.65%, respectively, and increased the level of IL-10 by 44.97 ± 4.57%. In a scratch assay, it promoted wound healing, achieving a closure rate of 97.55 ± 2.77% after 36 h. In vivo studies revealed that the OR@ZIF-8@HA treatment group achieved a wound healing rate of 96.14 ± 4.12% on day 14. Conclusions: The OR@ZIF-8@HA composite hydrogel effectively overcomes the limitations of OR application via intelligent pH-responsive delivery. Through synergistic multi-mechanistic actions, it significantly accelerates frostbite wound healing, offering a novel and efficient therapeutic strategy for frostbite management.
Objective: To systematically evaluate the potential of Saussurea involucrata cultures (SICs) against high-altitude illness under hypobaric hypoxia and establish a progressive experimental evidence chain covering acute hypoxia tolerance enhancement and acute/chronic hypoxic injury protection. Methods: A tiered experimental strategy was employed. Key findings were derived from primary rat models of acute (5500 m, 8 h) and chronic intermittent (5500 m, 8 h/d, 4–8 weeks) hypobaric hypoxia. A mouse acute tolerance model (10,000 m lethality, closed-system endurance) provided supplementary verification. Comprehensive analyses included survival, hemorheology, multi-organ function, and core mechanistic indicators of endothelial function and oxidative stress. Diamox, Rhodiola, and Compound Danshen Dripping Pills served as positive controls. Normoxic/hypoxic blank groups served as negative controls. Results: SICs significantly enhanced acute hypoxia tolerance in mice. In the rat models, SICs demonstrated dose-dependent and selective regulation of the endothelial–oxidative stress/hemorheology axis. Specifically, it downregulated endothelin-1, upregulated nitric oxide, enhanced total antioxidant capacity, and improved chronic hypoxia-induced blood hyperviscosity. Medium doses showed consistent optimal efficacy. SICs had limited effects on macroscopic organ remodeling. Conclusions: The core protective effect of SICs lies in enhancing hypoxic tolerance and selectively modulating the interconnected pathways of endothelial function, oxidative stress, and microcirculatory health. This mechanistic profile supports its potential as a preventive or early adjuvant intervention for high-altitude illness, providing a systematic preclinical foundation for translational development.