The scientific premise rests on a growing appreciation of ferroptosis as a driver of diabetic pathology. Unlike apoptosis, ferroptosis kills cells through runaway lipid peroxidation: reactive oxygen species accumulate, iron metabolism goes awry, and the fatty membranes of cells are oxidized until they rupture. In high-glucose environments resembling diabetic tissue, the researchers showed that human umbilical vein endothelial cells, the workhorses of new blood vessel formation, suffered precisely this fate. Exposure to 33 millimolar glucose for 48 hours reduced cell viability, crippled migration in scratch and Transwell assays, and simplified the vascular networks the cells could form on Matrigel. At the molecular level, the high-glucose conditions suppressed GPX4, the glutathione-dependent enzyme that normally detoxifies lipid peroxides, while raising levels of NCOA4, a mediator of ferritinophagy that liberates iron from storage, and TFR1, the transferrin receptor that imports more iron. The result was a measurable surge in intracellular reactive oxygen species, malondialdehyde, a canonical marker of lipid peroxidation, and free ferrous iron.

Into this pathological picture the team introduced baicalein, a 5,6,7-trihydroxyflavone extracted from the roots of Scutellaria baicalensis, a plant long used in traditional East Asian medicine. The compound’s triple hydroxyl arrangement gives it exceptional antioxidant capacity, allowing it to neutralize reactive oxygen species directly and to chelate ferrous iron into stable complexes that cannot participate in Fenton reactions, the chemistry that converts hydrogen peroxide into the most destructive hydroxyl radicals. In the new experiments, baicalein at 20 micromolar, a concentration shown to be non-toxic up to 100 micromolar, largely restored endothelial viability, migration and tube formation under both high-glucose stress and treatment with RSL-3, a chemical that induces ferroptosis by covalently inactivating GPX4. The drug upregulated GPX4, dampened NCOA4 and TFR1, and pushed down cellular levels of reactive oxygen species, malondialdehyde and free iron, confirming that its protective effect operates specifically through the ferroptosis machinery rather than through some generic stress response.

The mechanistic core of the study lies in the Keap1/NRF2/HIF-1α signaling axis. Under resting conditions, the protein Keap1 binds NRF2, the master transcriptional regulator of antioxidant defense, and tags it for degradation. Oxidative stress normally pries this pair apart, freeing NRF2 to enter the nucleus and activate antioxidant response elements in genes such as GPX4. The researchers found that high glucose or RSL-3 pushed the system the wrong way, elevating Keap1 while suppressing NRF2 and, downstream, HIF-1α, the oxygen-sensing transcription factor that drives vascular endothelial growth factor production and angiogenesis. Molecular docking predicted that baicalein binds the Kelch domain of Keap1 with a favorable energy of minus 8.73 kilocalories per mole, forming hydrogen bonds with residues including VAL-420, VAL-512 and VAL-467. Co-immunoprecipitation then confirmed that baicalein promotes dissociation of the Keap1–NRF2 complex in cells. When the team knocked down NRF2 with lentiviral shRNA, or blocked it pharmacologically with ML385, baicalein’s anti-ferroptotic protection collapsed, GPX4 fell, iron import genes rose, and oxidative markers climbed, demonstrating that NRF2 is essential to the drug’s action and that NRF2 in turn sustains HIF-1α expression through a validated antioxidant response element in the HIF1A enhancer.

Translating this chemistry into a clinically usable dressing required solving a stubborn formulation problem: baicalein is poorly soluble in water, so free drug applied to a wound would never reach therapeutic concentrations. The team’s solution borrows from plant defense chemistry itself. Glycyrrhizic acid, a natural triterpenoid from licorice, self-assembles in aqueous solution into nanofibers that encapsulate baicalein, dramatically enhancing its solubility and enabling sustained release. These nanofibers were then complexed with gelatin and zinc ions at 40 degrees Celsius and gelled overnight, producing a dual physically cross-linked network held together by metal-coordination bonds between zinc and the carboxyl groups of glycyrrhizic acid and by hydrogen bonds between gelatin and the nanofibers. Infrared spectroscopy tracked the structural evolution, showing a broadened, shifted O–H peak at 3267 inverse centimeters indicative of the hydrogen-bonded network and the disappearance of characteristic baicalein-glycyrrhizic acid peaks upon zinc coordination.

Mechanical testing revealed a material well matched to living tissue. Rheology confirmed solid-dominated viscoelasticity, with the storage modulus exceeding the loss modulus across the tested frequency range, and the formulation containing 0.4 percent baicalein-glycyrrhizic acid nanofibers showed the highest storage modulus and greatest critical strain. Uniaxial compression yielded a Young’s modulus of about 33 kilopascals with fracture at 42 percent strain, soft enough to deform with skin, while lap-shear testing on porcine skin recorded an adhesive strength of roughly 62 kilopascals, enough to keep the patch anchored through joint flexion. The hydrogel also proved environmentally responsive. At physiological pH 7.4 it swelled to 186 percent of its dry weight, but at the acidic pH 5.5 characteristic of diabetic wounds, protonation of carboxyl groups compacted the network and limited swelling to 106 percent. Drug release was correspondingly slower in acid, extending baicalein retention exactly where diabetic wounds need it most, although matrix metalloproteinase-9 in simulated wound fluid accelerated degradation, a property that could allow the dressing to yield its payload as it dissolves in the enzyme-rich wound bed.

Safety and antimicrobial performance rounded out the preclinical profile. Live-dead staining and proliferation assays showed the composite hydrogel actually promoted endothelial cell growth, hemolysis rates stayed below the 5 percent safety threshold, and histological examination of heart, liver, spleen, lung and kidney tissue from treated rats revealed no pathological changes. Released baicalein is metabolized locally and systemically by glucuronidation and sulfation and cleared renally, limiting systemic exposure. Against Staphylococcus aureus and Escherichia coli, the two flagship wound pathogens, the components showed only modest activity individually, but the full composite achieved a bactericidal rate exceeding 70 percent against S. aureus, a synergy attributed to baicalein and glycyrrhizic acid disrupting bacterial walls while zinc ions inhibit metabolic enzymes. When cells were challenged with RSL-3, the hydrogel reduced reactive oxygen species, malondialdehyde and ferrous iron more effectively than any other formulation, approaching the performance of Ferrostatin-1, a benchmark ferroptosis inhibitor, and it also blunted hydrogen peroxide-induced apoptosis by activating the PI3K/Akt survival pathway.

The decisive test came in diabetic rats. The team induced diabetes with streptozotocin, excised one-centimeter full-thickness wounds on the animals’ backs, and treated them with phosphate buffer, free baicalein, baicalein-glycyrrhizic acid nanofibers, the gelatin-zinc scaffold without drug, or the complete composite. By day nine the full hydrogel had closed 96.4 percent of wound area, compared with 89.1 percent for the drug-free scaffold, 84.6 percent for the nanofibers alone and 76.5 percent for free baicalein. Hematoxylin and eosin staining showed reduced wound width and complete epithelialization in the composite group, while Masson’s trichrome revealed abundant, well-organized collagen deposition. Immunofluorescence for CD31 and alpha-smooth muscle actin documented a surge in mature new blood vessels, and immunohistochemistry confirmed the molecular signature seen in the dish: GPX4 up, NCOA4 and TFR1 down, Keap1 suppressed, and both NRF2 and HIF-1α elevated. Tumor necrosis factor-alpha levels fell as well, pointing to a calming of the chronic inflammation that normally stalls diabetic repair.

The work, led by Haiting Zou, Qian Tan and colleagues at Nanjing institutions, positions the baicalein-loaded glycyrrhizic acid hydrogel as a multifunctional platform that simultaneously fights infection, quenches oxidative stress, blocks ferroptotic endothelial death and stimulates revascularization, all from a single bio-derived dressing. Compared with earlier baicalein delivery systems built on Schiff-base chemistry, zeolitic imidazolate frameworks or chitosan, the dual-crosslinked supramolecular network offers superior mechanical strength and pH-tuned drug retention. The researchers caution that the findings rest on rodent models and that the Keap1/NRF2/HIF-1α mechanism, while strongly supported by knockdown, inhibitor and docking data, operates within a web of additional pathways including PI3K/Akt-mediated survival signaling. Even so, the strategy of targeting ferroptosis through a self-assembling, plant-inspired biomaterial offers a compelling template for the next generation of intelligent wound dressings, and it underscores how molecules refined by plant evolution over millions of years can be re-engineered, with the help of licorice nanofibers and a dash of zinc, into therapies for one of modern diabetes care’s most intractable problems.

Subject of Research: A supramolecular hydrogel delivering baicalein to inhibit ferroptosis and accelerate diabetic wound healing

Article Title: Bio-inspired supramolecular hydrogel inhibits ferroptosis to accelerate diabetic wound healing

Article References: Zou, H., Chen, J., Huang, Y., Li, J., Yuan, X., Chen, T., Ding, Y., Yang, P., Zheng, D., Chen, G., & Tan, Q. (2026). Bio-inspired supramolecular hydrogel inhibits ferroptosis to accelerate diabetic wound healing. Journal of Advanced Research, 88, 841-853. https://doi.org/10.1016/j.jare.2026.01.024

Image Credits: AI Generated

DOI: Not provided

Keywords: diabetic wounds, ferroptosis, baicalein, glycyrrhizic acid, hydrogel, NRF2, HIF-1α, GPX4, angiogenesis, zinc ions, wound dressing, nanofibers

The scale of the problem is enormous. In 2012 alone, the United States spent nearly 20 billion dollars on chronic wound care, while the United Kingdom reported expenditures of roughly 184 million pounds. Despite that investment, conventional dressings—films, foams, wafers, nanofibers, patches, and standard bandages—continue to fall short. The review catalogues their recurring weaknesses: poor antibacterial efficacy, inadequate mechanical strength, low exudate absorption, insufficient gas permeability, painful removal, and a failure to sustain the moist microenvironment that skin needs to regenerate. Chronic wounds compound the difficulty because they become trapped in a prolonged inflammatory state, failing to progress through the normal sequence of hemostasis, inflammation, proliferation, and remodeling, and they are frequently life-threatening when infection takes hold.

Hydrogels offer a fundamentally different starting point. These three-dimensional hydrophilic polymer networks, built from natural polymers such as alginate, gelatin, and chitosan or synthetic ones like polyvinyl alcohol and polyethylene glycol, can absorb and retain large volumes of water, mimic the extracellular matrix, and support cell proliferation, migration, and angiogenesis. The review distinguishes three structural classes. Physical hydrogels, held together by hydrogen bonds, ionic interactions, and hydrophobic forces, are reversible and stimuli-responsive, making them injectable and ideal for minimally invasive delivery, though they lack mechanical durability. Chemical hydrogels, crosslinked covalently with agents such as genipin or EDC/NHS chemistry, are robust and stable, enabling sustained drug release and long-term implantation, but can carry cytotoxicity risks from crosslinkers. Hybrid hydrogels combine both networks, balancing strength with responsiveness and enabling self-healing, shape-memory, and on-demand drug release at dynamic wound interfaces.

The engineering behind these materials is increasingly sophisticated. The authors describe how the Flory–Rehner theory of polymer swelling provides a quantitative framework for tuning hydrogel expansion to match the viscoelastic properties of native tissue. Crosslinking strategy determines nanoparticle loading, spatial distribution, and release kinetics: free radical polymerization yields tight pore networks that retain nanoparticles and prolong release, while ionic calcium–alginate crosslinking permits faster diffusion and burst release. Surface interactions—electrostatic attraction, hydrogen bonding, hydrophobic association—between nanoparticles and the polymer matrix further shape biological performance. In a particularly promising green-synthesis approach, phytochemicals from medicinal plants rich in flavonoids, phenolics, alkaloids, and terpenoids are being formulated into nanoparticles, dramatically improving their solubility, bioavailability, and controlled delivery thanks to high surface-area-to-volume ratios, then embedded into hydrogels for topical wound application.

Among the nanomaterials reviewed, silver nanoparticles remain the most extensively studied antimicrobial agents. In supramolecular hydrogels, silver complexes with polysaccharide chains to enable prolonged, pH- and temperature-responsive release that eradicates bacterial bioburden while simultaneously suppressing inflammatory cytokines, shifting the wound environment toward resolution and regeneration. Even more striking are dopamine-modified gelatin constructs carrying silver nanoparticles, which combine radical-scavenging antioxidant activity with synergistic antibacterial action under near-infrared irradiation, using photothermal conversion to accelerate healing and enhance epithelial and dermal appendage regeneration. In vivo studies show that silver-loaded hydrogels shorten the inflammatory phase and speed wound closure, performing a dual role as antimicrobial shield and immune modulator.

Copper nanoparticles add another mechanistic dimension. Embedded within methacrylate-modified gelatin networks, they exploit localized surface plasmon resonance under near-infrared light to generate localized heat that intensifies bactericidal activity in situ. Released copper ions disrupt bacterial membranes while also acting as an essential cofactor in angiogenesis, driving fibroblast proliferation and endothelial cell tube formation. Animal studies confirm that copper nanoparticle hydrogels combined with photothermal therapy markedly restrict infection, reduce inflammation, and accelerate granulation and vascularization. Gold nanoparticles, meanwhile, contribute robust surface chemistry and stability as carriers for growth factors and as components of plasmon-enhanced dressings that couple therapy with wound monitoring.

Zinc and cerium bring immunomodulatory and antioxidant firepower. Glycyrrhizic acid hydrogels crosslinked with zinc ions generate an intrinsically immunoregulatory matrix that shifts macrophages from the pro-inflammatory M1 phenotype toward the pro-healing M2 state without any exogenous additives—a decisive advantage in diabetic wounds where persistent M1-driven inflammation blocks repair. Zinc oxide nanoparticles contribute antimicrobial and enzyme-mimetic antioxidative functions that counter oxidative stress. Ceria nanoparticles, often incorporated into cerium-containing bioactive glass within gelatin methacryloyl hydrogels, dynamically scavenge reactive oxygen species through the redox cycling of cerium ions while stimulating endothelial migration and neovascularization, attacking the twin bottlenecks of chronic wounds: infection and inadequate blood vessel formation.

Polydopamine nanoparticles and chitosan-based systems round out the toolkit. Polydopamine serves as adhesive, antioxidant, photothermal agent, and secondary functionalization platform—when hybridized with silver it produces hydrogels that are self-healing, injectable, remoldable, and light-responsive, conforming to irregular wound shapes and allowing painless removal and reapplication. Chitosan’s cationic nature lets it bind directly to anionic bacterial membranes, delivering intrinsic bactericidal, hemostatic, and anti-inflammatory action without external agents, and carboxymethyl chitosan hydrogels crosslinked with nanocellulose can self-heal and dissolve on demand, minimizing scar formation in burn care. The review also highlights structural reinforcement with reduced graphene oxide and cellulose nanocrystals, glucose oxidase-modified hydrogels that release exosomes in response to elevated glucose in diabetic wounds, enzyme-responsive matrices cleaved by overexpressed matrix metalloproteinases, ROS-labile linkers that trigger antioxidant release selectively, and mussel-inspired catechol-functionalized adhesives borrowed from marine biology.

Preclinical outcomes across these platforms are consistently encouraging: accelerated wound closure, decreased microbial burden, enhanced cellular activity, improved collagen deposition, and vascular network formation. But the authors are careful about translation. Remaining barriers include nanoparticle aggregation, dose-dependent cytotoxicity, long-term tissue retention, variability in synthesis reproducibility, sterilization limitations, and regulatory compliance. Looking ahead, they point to the integration of biosensors, artificial intelligence-driven stimulus-responsive delivery, and patient-specific 3D-printed hydrogel platforms tailored to individual wound geometries and biochemistries. The trajectory, they argue, is a shift from passive to proactive wound care—smart, adaptable, multifunctional systems that sense the wound microenvironment and respond in real time.

What makes this review resonate beyond the laboratory is the convergence it documents. Nanotechnology, polymer chemistry, immunology, and biofabrication are no longer parallel tracks; they are being fused into single dressings that kill bacteria, quench oxidative stress, reprogram immune cells, deliver growth factors on cue, and monitor their own performance. For millions of patients whose wounds refuse to heal—and for health systems spending billions managing them—nanoparticle-infused hydrogels represent one of the most credible paths yet from bench to bedside.

Subject of Research: Nanoparticle-infused hydrogel dressings for enhanced wound healing and tissue regeneration

Article Title: Enhancing wound healing with nanoparticle-infused hydrogels: a review of current applications and future prospects

Article References: Enhancing wound healing with nanoparticle-infused hydrogels: a review of current applications and future prospects. (n.d.). https://doi.org/10.1007/s44340-025-00030-1

Image Credits: AI Generated

DOI: 10.1007/s44340-025-00030-1

Keywords: hydrogels, wound healing, nanoparticles, antimicrobial, tissue regeneration, smart wound dressings, stimuli-responsive hydrogels, silver nanoparticles, zinc oxide nanoparticles, ceria nanoparticles, diabetic wounds, nanobiotechnology