Biomaterials for immunomodulation in wound healing

Diabetic Foot Ulcers: Pathophysiology, Immune Dysregulation, and Emerging Therapeutic Strategies

Diabetic foot ulcers (DFUs) are among the most common and debilitating complications of diabetes mellitus (DM), affecting approximately 15-25% of patients and contributing to over 85% of non-traumatic amputations. DFUs impose a substantial clinical and economic burden due to high recurrence rates, prolonged wound care, and frequent hospitalizations, accounting for billions in healthcare costs worldwide. The multifactorial pathophysiology of DFUs involves peripheral neuropathy, peripheral arterial disease, chronic inflammation, and impaired tissue regeneration. Recent studies underscore the importance of immune dysregulation-specifically macrophage polarization imbalance, regulatory T cell dysfunction, and neutrophil impairment-as central mechanisms in wound chronicity. These immune disruptions sustain a pro-inflammatory environment dominated by cytokines, such as TNF-α, IL-1β, and IL-6, which impair angiogenesis and delay repair. This review provides an updated synthesis of DFU pathogenesis, emphasizing immune dysfunction and its therapeutic implications. We examine emerging strategies in immunomodulation, regenerative medicine, and AI-based wound technologies, including SGLT2 inhibitors, biologics, stem cell therapies, and smart dressing systems. These approaches hold promise for accelerating healing, reducing amputation risk, and personalizing future DFU care.

Kinsenoside-Loaded Microneedle Accelerates Diabetic Wound Healing by Reprogramming Macrophage Metabolism via Inhibiting IRE1α/XBP1 Signaling Axis

Continuously bacterial infection, undue oxidative stress, and inflammatory responses in the skin tissue microenvironment determine the delayed healing outcome of diabetic wounds, which remain a tough clinical challenge and need multifaceted therapeutic strategies. In this work, HA-ADH/HA-QA-ALD-based hydrogel microneedle (HAQA-MN) with antimicrobial and antioxidative activities incorporating kinsenoside (KD) coated with macrophage membrane (M-KD) targeting inflammation relief is developed to improve the cutaneous micro-niche. KD is observed to trigger trimethylamine N-oxide-irritated proinflammatory macrophages repolarization from M1 state to anti-inflammatory M2 phenotype, and the underlying mechanism is due to drug-induced IRE1α/XBP1/HIF-1α pathway suppression, accompanied by diminution of glycolysis and enhancement of oxidative phosphorylation, resulting in proinflammatory cascade inhibition and anti-inflammatory signaling enhancement. The hydrazone cross-linked HAQA-MN possesses favorable biocompatibility, self-healing, controlled release of M-KD and excellent mechanical properties. Moreover, the MN patch remarkedly restrains the survival of E. coli and S. aureus and eliminates hydrogen peroxide to preserve cellular viability. Notably, M-KD@HAQA-MN array effectively ameliorates cutaneous inflammation and oxidative stress and facilitate angiogenesis and collagen deposition, thereby accelerating tissue regeneration of diabetic mice with a full-thickness skin defect model. Collectively, this study highlights a multifunctional MN platform as a promising candidate in clinical application for the treatment of diabetic wounds.

Advancement of Nanomaterials- and Biomaterials-Based Technologies for Wound Healing and Tissue Regenerative Applications

Patients and healthcare systems face significant social and financial challenges due to the increasing number of individuals with chronic external and internal wounds that fail to heal. The complexity of the healing process remains a serious health concern, despite the effectiveness of conventional wound dressings in promoting healing. Recent advancements in materials science and fabrication techniques have led to the development of innovative dressings that enhance wound healing. To further expedite the healing process, novel approaches such as nanoparticles, 3D-printed wound dressings, and biomolecule-infused dressings have emerged, along with cell-based methods. Additionally, gene therapy technologies are being harnessed to generate stem cell derivatives that are more functional, selective, and responsive than their natural counterparts. This review highlights the significant potential of biomaterials, nanoparticles, 3D bioprinting, and gene- and cell-based therapies in wound healing. However, it also underscores the necessity for further research to address the existing challenges and integrate these strategies into standard clinical practice.

Update on the Study of Angiogenesis in Surgical Wounds in Patients with Childhood Obesity

Background: Angiogenesis, the formation of new blood vessels from pre-existing ones, plays a pivotal role in wound healing, particularly in surgical contexts. Methods and results: However, this process can be significantly impaired in patients with childhood obesity, resulting in delayed healing and additional complications. The biological process of wound healing is complex, involving angiogenesis, cell proliferation, inflammation, and tissue remodeling. This review aims to explore recent advancements in research on angiogenesis in surgical wounds in patients with childhood obesity, with a focus on growth factors, inflammation, microcirculation, and innovative therapeutic strategies. Conclusions: It highlights therapeutic approaches such as the administration of growth factors and the application of biomaterials to enhance angiogenesis.

Empirical use, phytochemical, and pharmacological effects in wound healing activities of compounds in Diospyros leaves: A review of traditional medicine for potential new plant-derived drugs

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing extracts' activity is increasingly being studied in the field of traditional medicine. Among medicinal plants, Diospyros is known to have healing effects on wounds, along with activities such as anti-biofilm, anti-inflammatory, antibacterial, antioxidant, and regulation of the immune system. However, the current use of the leaves could be more optimal, and the scientific basis needs to be improved.

AIM OF THIS REVIEW

This review aimed to critically examine the literature on the traditional use and bioactive metabolites of several Diospyros species, demonstrating the significant potential in wound healing, antibacterial, anti-biofilm, regulatory effect on the immune system, anti-inflammatory, and antioxidant activities. The critical analysis was conducted to provide robust perspectives and recommendations for future studies on the use of Diospyros potential resources of wound healing material, including related activities.

MATERIALS AND METHODS

Exploratory studies on Diospyros species over the past 20 years were examined, with a focus on general information, practical use, secondary metabolite, and pharmacological activities related to wound healing. Data were meticulously collected from scientific databases including Scopus, ScienceDirect, Web of Science, Taylor & Francis, Google Scholar, PubMed as well as various botanical and biodiversity sources. Furthermore, manual searches were conducted to ensure comprehensive coverage. Reference manager software was used to manage articles and remove duplicates, then the gathered data were summarized and verified, ensuring the thoroughness and validity of the review process.

RESULTS

The results showed that Diospyros leaves have great potential to be harnessed as herbal medications, evidenced by both scientific findings and community uses. Various substances, including flavonoids, coumarins, tannins, terpenoids, steroids, lignans, quinones, and secoiridoids were identified. Chemical compound investigations in both in vivo and in vitro studies of Diospyros leaves reported wound healing activity, as well as antibacterial, anti-inflammatory, anti-biofilm, antioxidant, and immunomodulatory properties.

CONCLUSION

The review highlights the traditional uses and bioactive metabolites of Diospyros species in wound healing, identifying various beneficial compounds such as flavonoids and tannins. These compounds demonstrate various therapeutic effects, including antibacterial, anti-biofilm, anti-inflammatory, antioxidant, and immunomodulatory activities. Diospyros leaf extracts have a favorable safety profile, but further studies, including in vivo investigations and clinical trials, are necessary to confirm their efficacy and safety for clinical applications. Diospyros leaf extracts have significant potential for the development of wound healing substances due to the wide range of bioactivities targeting various stages of wound healing.

Trends in protein derived materials for wound care applications

Natural resource based polymers, especially those derived from proteins, have attracted significant attention for their potential utilization in advanced wound care applications. Protein based wound care materials provide superior biocompatibility, biodegradability, and other functionalities compared to conventional dressings. The effectiveness of various fabrication techniques, such as electrospinning, phase separation, self-assembly, and ball milling, is examined in the context of developing protein-based materials for wound healing. These methods produce a wide range of forms, including hydrogels, scaffolds, sponges, films, and bioinspired nanomaterials, each designed for specific types of wounds and different stages of healing. This review presents a comprehensive analysis of recent research that investigates the transformation of proteins into materials for wound healing applications. Our focus is on essential proteins, such as keratin, collagen, gelatin, silk, zein, and albumin, and we emphasize their distinct traits and roles in wound care management. Protein-based wound care materials show promising potential in biomedical engineering, offering improved healing capabilities and reduced risks of infection. It is crucial to explore the potential use of these materials in clinical settings while also addressing the challenges that may arise from their commercialization in the future.

A microenvironment-adaptive GelMA-ODex@RRHD hydrogel for responsive release of H2S in promoted chronic diabetic wound repair

Chronic diabetic wounds present significant treatment challenges due to their complex microenvironment, often leading to suboptimal healing outcomes. Hydrogen sulfide (H2S), a crucial gaseous signaling molecule, has shown great potential in modulating inflammation, oxidative stress and extracellular matrix remodeling, which are essential for effective wound healing. However, conventional H2S delivery systems lack the adaptability required to meet the dynamic demands of different healing stages, thereby limiting their therapeutic efficacy. To address this, we developed an injectable, ROS-responsive H2S donor system integrated within a gelatin methacryloyl (GelMA) hydrogel matrix, forming a double-network hydrogel (GelMA-ODex@RRHD). The injectability of this hydrogel allows for minimally invasive application, conforming closely to wound contours and ensuring uniform distribution. The incorporation of oxidatively modified dextran derivatives (ODex) not only preserves biocompatibility but also enables the chemical attachment of ROS-responsive H2S donors. The GelMA-ODex@RRHD hydrogel releases H2S in response to oxidative stress, optimizing the environment for cell growth, modulating macrophage polarization and supporting vascular regeneration. This innovative material effectively suppresses inflammation during the initial phase, promotes tissue regeneration in the proliferative phase and facilitates controlled matrix remodeling in later stages, ultimately enhancing wound closure and functional recovery. The H2S released by GelMA-ODex@RRHD not only expedited the process of wound healing but also improved the biomechanical characteristics of newborn skin in diabetic mice, particularly in terms of stiffness and elasticity. This enhancement resulted in the skin quality being more similar to normal skin during the wound healing process. By aligning therapeutic delivery with the natural healing process, this approach offers a promising pathway toward more effective and personalized treatments for chronic diabetic wounds.

Wound Closure Promotion by Leucine-Based Pseudo-Proteins: An In Vitro Study

Our research explores leucine-based pseudo-proteins (LPPs) for advanced wound dressings, focusing on their effects on wound healing in an in vitro model. We assessed three types of LPP films for their ability to enhance wound closure rates and modulate cytokine production. They all significantly improved wound closure compared to traditional methods, with the 8L6 and copolymer films showing the most pronounced effects. Notably, the latter exhibited an optimal cytokine profile: an initial burst of pro-inflammatory TNF-α, followed by a controlled release of IL-6 during the proliferative phase and a significant increase in anti-inflammatory IL-10 during remodeling. This balanced cytokine response suggests that the copolymer film not only accelerates wound closure but also supports a well-regulated healing process, potentially reducing fibrosis and abnormal scarring, underscoring the potential of copolymer LPPs as advanced wound dressing materials. Future research will aim to elucidate the specific signaling pathways activated by the copolymer LPP to better understand its mechanism of action. Overall, LPP films offer a promising approach to improving wound care and could lead to more effective treatments for complex wounds.