Sustained Releasable Copper and Zinc Biogenic Ions Co-Assembled in Metal-Organic Frameworks Reinforced Bacterial Eradication and Wound Mitigation in Diabetic Mice

Metal ion formulations for diabetic wound healing: Mechanisms and therapeutic potential

Metals are vital in human physiology, which not only act as enzyme catalysts in the processes of superoxide dismutase and glucose phosphorylation, but also affect the redox process, osmotic adjustment, metabolism and neural signals. However, metal imbalances can lead to diseases such as diabetes, which is marked by chronic hyperglycemia and affects wound healing. The hyperglycemic milieu of diabetes impairs wound healing, posing significant challenges to patient quality of life. Wound healing encompasses a complex cascade of hemostasis, inflammation, proliferation, and remodeling phases, which are susceptible to disruption in hyperglycemic conditions. In recent decades, metals have emerged as critical facilitators of wound repair by enhancing antimicrobial properties (e.g., iron and silver), providing angiogenic stimulation (copper), promoting antioxidant activity and growth factor synthesis (zinc), and supporting wound closure (calcium and magnesium). Consequently, research has pivoted towards the development of metal ion-based therapeutics, including innovative formulations such as nano-hydrogels, nano-microneedle dressings, and microneedle patches. Prepared by combining macromolecular materials such as chitosan, hyaluronic acid and sodium alginate with metals, aiming at improving the management of diabetic wounds. This review delineates the roles of key metals in human physiology and evaluates the application of metal ions in diabetic wound management strategies.

Enhancing antibacterial properties by regulating valence configurations of copper: a focus on Cu-carboxyl chelates

Optimizing the antibacterial effectiveness of copper ions while reducing environmental and cellular toxicity is essential for public health. A copper chelate, named PAI-Cu, is skillfully created using a specially designed carboxyl copolymer (a combination of acrylic and itaconic acids) with copper ions. PAI-Cu demonstrates a broad-spectrum antibacterial capability both in vitro and in vivo, without causing obvious cytotoxic effects. When compared to free copper ions, PAI-Cu displays markedly enhanced antibacterial potency, being about 35 times more effective against Escherichia coli and 16 times more effective against Staphylococcus aureus. Moreover, Gaussian and ab initio molecular dynamics (AIMD) analyses reveal that Cu+ ions can remain stable in the carboxyl compound's aqueous environment. Thus, the superior antibacterial performance of PAI-Cu largely stems from its modulation of copper ions between mono- and divalent states within the Cu-carboxyl chelates, especially via the carboxyl ligand. This modulation leads to the generation of reactive oxygen species (˙OH), which is pivotal in bacterial eradication. This research offers a cost-effective strategy for amplifying the antibacterial properties of Cu ions, paving new paths for utilizing copper ions in advanced antibacterial applications.

Carbomer Hydrogel Composed of Cu2O and Hematoporphyrin Monomethyl Ether Promotes the Healing of Infected Wounds

Infectious wounds pose a significant challenge in the field of wound healing primarily due to persistent inflammation and the emergence of antibiotic-resistant bacteria. To combat these issues, the development of an effective wound dressing that can prevent infection and promote healing is of the utmost importance. Photodynamic therapy (PDT) has emerged as a promising noninvasive treatment strategy for tackling antibiotic-resistant bacteria. A biodegradable photosensitizer called hematoporphyrin monomethyl ether (HMME) has shown potential in generating reactive oxygen species (ROS) upon laser activation to combat bacteria. However, the insolubility of HMME limits its antibacterial efficacy and its ability to facilitate skin healing. To overcome these limitations, we have synthesized a compound hydrogel by combining carbomer, HMME, and Cu2O nanoparticles. This compound hydrogel exhibits enhanced antimicrobial ability and excellent biocompatibility and promotes angiogenesis, which is crucial for the healing of skin defects. By integrating the benefits of HMME, Cu2O nanoparticles, and the gel-forming properties of carbomer, this compound hydrogel shows great potential as an effective wound dressing material. In summary, the compound hydrogel developed in this study offers a promising solution for infectious wounds by addressing the challenges of infection prevention and promoting skin healing. This innovative approach utilizing PDT and the unique properties of the compound hydrogel could significantly improve the outcomes of wound healing in clinical settings.

Exogeneous metal ions as therapeutic agents in cardiovascular disease and their delivery strategies

Metal ions participate in many metabolic processes in the human body, and their homeostasis is crucial for life. In cardiovascular diseases (CVDs), the equilibriums of metal ions are frequently interrupted, which are related to a variety of disturbances of physiological processes leading to abnormal cardiac functions. Exogenous supplement of metal ions has the potential to work as therapeutic strategies for the treatment of CVDs. Compared with other therapeutic drugs, metal ions possess broad availability, good stability and safety and diverse drug delivery strategies. The delivery strategies of metal ions are important to exert their therapeutic effects and reduce the potential toxic side effects for cardiovascular applications, which are also receiving increasing attention. Controllable local delivery strategies for metal ions based on various biomaterials are constantly being designed. In this review, we comprehensively summarized the positive roles of metal ions in the treatment of CVDs from three aspects: protecting cells from oxidative stress, inducing angiogenesis, and adjusting the functions of ion channels. In addition, we introduced the transferability of metal ions in vascular reconstruction and cardiac tissue repair, as well as the currently available engineered strategies for the precise delivery of metal ions, such as integrated with nanoparticles, hydrogels and scaffolds.