Advanced Nitric Oxide Generating Nanomedicine for Therapeutic Applications

A molybdenum sulfide based nitric oxide controlled release oral gel for rapid healing of oral mucosal ulcers

Oral mucosal ulcer is the most prevalent oral mucosal lesion, affecting over 25 % of general population. The current treatment regimens lack efficacy in addressing challenges such as wound bleeding, bacterial infection and inflammation on a continuous basis. Hence, a multi-functional oral gel (termed MPCST) with a long-acting duration is designed. It is based on a tannic acid-thioctic acid (TATA) supramolecular hydrogel which absorbs tissue exudate while exhibiting robust tissue adhesion properties. To form MPCST, TATA is loaded with MPCS, which are composed of polydopamine (PDA)-coated molybdenum disulfide (MoS2) nanoflakes (MoS2@PDA) with high photothermal conversion efficiency, nitric oxide (NO) precursor nitroprusside (SNP) and cerium oxide (CeO2) with high reactive oxygen species (ROS) scavenging rate. Upon exposure to 808 nm near-infrared (NIR) irradiation, MPCS rapidly heats up and releases NO to promote angiogenesis, while exhibiting strong ROS scavenging, antibacterial (including oral common Streptococcus mutans), and anti-inflammatory properties. Animal experiments show that the MPCST oral gel, composed of MPCS and TATA hydrogel, exhibits superior therapeutic efficacy compared to the commonly used dexamethasone patch.

Nitric oxide-based multi-synergistic nanomedicine: an emerging therapeutic for anticancer

Gas therapy has emerged as a promising approach for treating cancer, with gases like NO, H2S, and CO showing positive effects. Among these, NO is considered a key gas molecule with significant potential in stopping cancer progression. However, due to its high reactivity and short half-life, delivering NO directly to tumors is crucial for enhancing cancer treatment. NO-driven nanomedicines (NONs) have been developed to effectively deliver NO donors to tumors, showing great progress in recent years. This review provides an overview of the latest advancements in NO-based cancer nanotherapeutics. It discusses the types of NO donors used in current research, the mechanisms of action behind NO therapy for cancer, and the different delivery systems for NO donors in nanotherapeutics. It also explores the potential of combining NO donors with other treatments for enhanced cancer therapy. Finally, it examines the future prospects and challenges of using NONs in clinical settings for cancer treatment.

Nitric Oxide-Photodelivering Materials with Multiple Functionalities: From Rational Design to Therapeutic Applications

The achievement of materials that are able to release therapeutic agents under the control of light stimuli to improve therapeutic efficacy is a significant challenge in health care. Nitric oxide (NO) is one of the most studied molecules in the fascinating realm of biomedical sciences, not only for its crucial role as a gaseous signaling molecule in the human body but also for its great potential as an unconventional therapeutic in a variety of diseases including cancer, bacterial and viral infections, and neurodegeneration. Handling difficulties due to its gaseous nature, reduced region of action due to its short half-life, and strict dependence of the biological effects on its concentration and generation site are critical questions to be solved for appropriate therapeutic uses of NO. Light-activatable NO precursors, namely, NO photodonors (NOPDs), address the above issues since they are stable in the dark and permit in a noninvasive fashion the remote-controlled delivery of NO on demand with great spatiotemporal precision. Engineering biocompatible materials with NOPDs and their combination with additional imaging, therapeutic, and phototherapeutic components leads to intriguing light-responsive multifunctional constructs exhibiting promising potential for biomedical applications. This contribution illustrates the most significant progress made over the last five years in achieving engineered materials including nanoparticles, gels, and thin films, sharing the common feature to deliver NO under the exclusive control of the biocompatible visible/near infrared light inputs. We will highlight the logical design behind the fabrication of these systems, illustrating the potential therapeutic applications with particular emphasis on cancer and bacterial infections.

Neutrophil extracellular traps in wound healing

Wound healing is a complex and orchestrated process that involves hemostasis, inflammation, proliferation, and tissue remodeling. Neutrophil extracellular traps (NETs) are intricate web-like structures released by neutrophils, comprising decondensed chromatin, myeloperoxidase (MPO), and neutrophil elastase (NE), which play vital roles in regulating neutrophil-mediated immune regulation. While NETs contribute to wound healing, excessive activation induced by dysregulated inflammation can hinder the healing process. Understanding the pivotal role of NETs in wound healing and tissue remodeling, as well as their intricate interactions within the wound microenvironment, presents opportunities for innovative wound healing strategies. In this review we discuss the process of NET formation, explore the interactions between NETs and skin cells, and examine therapeutic strategies targeting NETs and drug delivery platforms to accelerate wound healing. Additionally, we discuss current clinical investigations and research challenges towards advancing wound care practices.

A photo-modulated nitric oxide delivering hydrogel for the accelerated healing of biofilm infected chronic wounds

Biofilm infection and impaired healing of chronic wounds are posing tremendous challenges in clinical practice. In this study, we presented a versatile antimicrobial hydrogel capable of delivering nitric oxide (NO) in a controllable manner to dissipate biofilms, eliminate microorganisms, and promote the healing of chronic wounds. This hydrogel was constructed by Schiff-base crosslinking of oxidized dextran and antimicrobial peptide ε-poly-lysine, further encapsulating photothermal nanoparticles bearing NO donor. This hydrogel could continuously and slowly release NO, effectively dissipating biofilms, and promoting the proliferation of mouse fibroblasts and the migration of endothelial cells. Upon exposure to NIR laser irradiation, the hydrogel generated hyperthermia and rapidly released NO, resulting in the efficient elimination of a broad spectrum of drug-resistant Gram-positive/negative bacterial and fungal biofilms through the synergistic effects of NO, photothermal therapy, and the antibacterial peptide. Notably, the hydrogel demonstrated exceptional in vivo therapeutic outcomes in accelerating the healing process of mice diabetic wounds infected with methicillin-resistant Staphylococcus aureus by successfully eliminating biofilm infection, regulating inflammation, and facilitating angiogenesis and collagen deposition. Overall, this proposed hydrogel shows great promise in accommodating the various demands of the complex repair process of chronic wounds infected with biofilms. STATEMENT OF SIGNIFICANCE: The presence of biofilm infections and underlying dysfunctions in the healing process made chronic wound become stuck in the inflammation stage and difficult to heal. This work developed a NIR laser-modulated three-stage NO-releasing versatile antimicrobial hydrogel (DEPN) exhibiting good therapeutic efficacy for chronic wound. This DEPN hydrogel could inherently and slowly released NO to disperse biofilm. Upon NIR laser irradiation, the DEPN hydrogel generated hyperthermia and induced a rapid burst release of NO effectively eliminating a broad spectrum of drug-resistant bacterial and fungal biofilms. Subsequently, the DEPN hydrogel continually release NO slowly to promote the tissue remolding. This DEPN hydrogel displays great potential in treatment of chronic wounds infected with biofilm.

Lignin-Based Visible Light-Triggered Nitric Oxide Nanogenerator for Antibacterial Applications

Nitric oxide (NO) has received growing attention as an effective antibacterial agent with broad-spectrum activity and a low risk of resistance. However, it remains challenging to develop effective, controllable, and biocompatible NO-releasing materials. Here, we report a novel NO nanogenerator (AL-BNN6-PEG) self-assembled by lignin, a UV-absorbing and hydrophobic NO donor (N,N'-disec-butyl-N,N'-dinitroso-1,4-phenylenediamine, BNN6), and PEG-DSPE2000. It was discovered that upon visible light irradiation (450-460 nm), BNN6 can be decomposed by lignin within micellar nanoparticles via a photoinduced electron transfer mechanism in the aqueous medium. Lignin not only served as a sustainable carrier, enhancing the water dispersity of BNN6, but also acted as a biocompatible photosensitizer, triggering BNN6 decomposition with the concomitant release of NO. As a result, the micellar nanoparticles displayed superior antibacterial effects against Gram-negative and Gram-positive bacteria upon visible light illumination. Moreover, MTT assay revealed the negligible cytotoxic effect of the micellar nanoparticles to the mouse fibroblast cells (L929). This research provides more insight into the BNN6 decomposition mechanism and demonstrates a straightforward, effective, and biocompatible strategy for controlled NO-mediated antibacterial applications.

Multifunctional Molecular Hybrids Photoreleasing Nitric Oxide: Advantages, Pitfalls, and Opportunities

The multifaceted role nitric oxide (NO) plays in human physiology and pathophysiology has opened new scenarios in biomedicine by exploiting this free radical as an unconventional therapeutic against important diseases. The difficulties in handling gaseous NO and the strict dependence of the biological effects on its doses and location have made the light-activated NO precursors, namely NO photodonors (NOPDs), very appealing by virtue of their precise spatiotemporal control of NO delivery. The covalent integration of NOPDs and additional functional components within the same molecular skeleton through suitable linkers can lead to an intriguing class of multifunctional photoactivatable molecular hybrids. In this Perspective, we provide an overview of the recent advances in these molecular constructs, emphasizing those merging NO photorelease with targeting, fluorescent reporting, and phototherapeutic functionalities. We will highlight the rational design behind synthesizing these molecular hybrids and critically describe the advantages, drawbacks, and opportunities they offer in biomedical research.

Bionic aggregation-induced emission photosensitizer for enhanced cancer immunotherapy

Cold exposure therapy (CE), as an inexpensive method, has shown great potential in cancer therapy. Exploring the combined anti-tumor mechanism of CE and traditional therapies (such as photodynamic therapy (PDT)) is exciting and promising. Here, a bionic aggregation-induced emission photosensitizer system (named THL) is designed for combined CE to enhance anti-tumor immunotherapy. THL inherits the homologous targeting ability of tumor derived exosomes, promoting the enrichment of THL at the tumor site. Under external illumination, THL generates hydroxyl radicals and superoxide anions through type I PDT. In addition, mice are pretreated with cold exposure, which promotes THL mediated PDT and reactive oxygen species (ROS) generation by reducing the production of ATP and GSH in tumor tissue. This combination therapy increases production of ROS within the tumor, inhibits the growth of distant tumors, recurrent and rechallenged tumors and increases the number of cytotoxic CD8+T cells and memory T cells. Compared to PDT alone, combination therapy shows greater advantages in tumor immunotherapy. The combination therapy strategy provides new ideas for cancer immunotherapy.

Tumor Microenvironment-Activated In Situ Synthesis of Peroxynitrite for Enhanced Chemodynamic Therapy

Chemodynamic therapy (CDT) can induce cancer cell death through hydroxyl radicals (·OH) generated from Fenton or Fenton-like reactions. Compared with traditional therapies, CDT effectively overcomes inevitable drug resistance and exhibits low side effects. However, clinical application still faces challenges, primarily due to insufficient ·OH generation and the short-lifetime of ·OH in vivo. To address these challenges, we developed a peroxynitrite (ONOO-)-based CDT nanodrug (DOX@PMOF) composed of MOF-199, NO donor (PArg), and nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) activator (doxorubicin, DOX). In DOX@PMOF, MOF-199 serves as both a carrier for loading DOX and a source of Cu+ for triggering CDT. Upon uptake by cancer cells, the high concentration of glutathione (GSH) reduces MOF-199 to Cu+, which then reacts with H2O2 to generate ·OH. Moreover, the released DOX upregulates NOX4 expression, leading to the elevated H2O2 level and thereby promoting a high-efficiency Fenton-like reaction for sufficient ·OH generation. Subsequently, PArg generates abundant NO in response to the tumor microenvironment, leading to a cascade of NO and ·OH for the in situ synthesis of ONOO-. ONOO- is more toxic and has a longer lifetime and diffusion distance than ·OH, resulting in a more effective CDT treatment. To further enhance the in vivo therapeutic effect, we coated DOX@PMOF with a homologous cell membrane to form an active tumor-targeting nanodrug (DOX@MPMOF), which has demonstrated the ability to effectively inhibit tumor growth and metastasis while exhibiting good biosafety.

Computer-aided nanodrug discovery: recent progress and future prospects

Nanodrugs, which utilise nanomaterials in disease prevention and therapy, have attracted considerable interest since their initial conceptualisation in the 1990s. Substantial efforts have been made to develop nanodrugs for overcoming the limitations of conventional drugs, such as low targeting efficacy, high dosage and toxicity, and potential drug resistance. Despite the significant progress that has been made in nanodrug discovery, the precise design or screening of nanomaterials with desired biomedical functions prior to experimentation remains a significant challenge. This is particularly the case with regard to personalised precision nanodrugs, which require the simultaneous optimisation of the structures, compositions, and surface functionalities of nanodrugs. The development of powerful computer clusters and algorithms has made it possible to overcome this challenge through in silico methods, which provide a comprehensive understanding of the medical functions of nanodrugs in relation to their physicochemical properties. In addition, machine learning techniques have been widely employed in nanodrug research, significantly accelerating the understanding of bio-nano interactions and the development of nanodrugs. This review will present a summary of the computational advances in nanodrug discovery, focusing on the understanding of how the key interfacial interactions, namely, surface adsorption, supramolecular recognition, surface catalysis, and chemical conversion, affect the therapeutic efficacy of nanodrugs. Furthermore, this review will discuss the challenges and opportunities in computer-aided nanodrug discovery, with particular emphasis on the integrated "computation + machine learning + experimentation" strategy that can potentially accelerate the discovery of precision nanodrugs.

Recent Advancements in Polymeric N-Nitrosamine-Based Nitric Oxide (NO) Donors and their Therapeutic Applications

Nitric oxide (NO), a gasotransmitter, is known for its wide range of effects in vasodilation, cardiac relaxation, and angiogenesis. This diatomic free radical also plays a pivotal role in reducing the risk of platelet aggregation and thrombosis. Furthermore, NO demonstrates promising potential in cancer therapy as well as in antibacterial and antibiofilm activities at higher concentrations. To leverage their biomedical activities, numerous NO donors have been developed. Among these, N-nitrosamines are emerging as a notable class, capable of releasing NO under suitable photoirradiation and finding a broad range of therapeutic applications. This review discusses the design, synthesis, and biological applications of polymeric N-nitrosamines, highlighting their advantages over small molecular NO donors in terms of stability, NO payload, and target-specific delivery. Additionally, various small-molecule N-nitrosamines are explored to provide a comprehensive overview of this burgeoning field. We anticipate that this review will aid in developing next-generation polymeric N-nitrosamines with improved physicochemical properties.

Comprehensive insights into fluorescent probes for the determination nitric oxide for diseases diagnosis

Nitric oxide (NO) plays an important role in multiple physiological processes of the body involved in regulation, such as cardiovascular relaxation, neural homeostasis, and immune regulation, etc. The real-time monitoring of NO is of great significance in the investigation of related disease mechanisms and the evaluation of pharmacodynamics. Fluorescent probes are considered as a highly promising approach for pharmaceutical analysis and bioimaging due to their non-invasive character, real-time detection, and high sensitivity. However, there are still some challenges in the determination of biological nitric oxide with fluorescent probes, such as low anti-interference ability, poor function modifiability, and low organ specificity. Therefore, it would be beneficial to develop a new generation of fluorescent probes for real-time bioimaging of NO in vivo after this systematic summary.

Near Infrared-Triggered Nitric Oxide-Release Nanovesicles with Mild-Photothermal Antibacterial and Immunomodulation for Healing MRSA-Infected Diabetic Wounds

Bacterial infection-induced excessive inflammation is a major obstacle in diabetic wound healing. Nitric oxide (NO) exhibits significant antibacterial activity but is extremely deficient in diabetes. Hence, a near-infrared (NIR)-triggered NO release system is constructed through codelivery of polyarginine (PArg) and gold nanorods (Au) in an NIR-activatable methylene blue (MB) polypeptide-assembled nanovesicle (Au/PEL-PBA-MB/PArg). Upon NIR irradiation, the quenched MB in the nanovesicles is photoactivated to generate more reactive oxygen species (ROS) to oxidize PArg and release NO in an on-demand controlled manner. With the specific bacterial capture of phenylboronic acid (PBA), NO elevated membrane permeability and boosted bacterial vulnerability in the photothermal therapy (PTT) of the Au nanorods, which is displayed by superior mild PTT antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) at temperatures < 49.7 °C in vitro. Moreover, in vivo, the antibacterial nanovesicles greatly suppressed the burst of MRSA-induced excessive inflammation, NO relayed immunomodulated macrophage polarization from M1 to M2, and the excessive inflammatory phase is successfully transferred to the repair phase. In cooperation with angiogenesis by NO, tissue regeneration is accelerated in MRSA-infected diabetic wounds. Therefore, nanoplatform has considerable potential for accelerating the healing of infected diabetic wounds.

Stimuli-Responsive NO Delivery Platforms for Bacterial Infection Treatment

The prevalence of drug-resistant bacterial infections has emerged as a grave threat to clinical treatment and global human health, presenting one of the foremost challenges in medical care. Thus, there is an urgent imperative to develop safe and efficacious novel antimicrobial strategies. Nitric oxide (NO) is a recognized endogenous signaling molecule, which plays a pivotal role in numerous pathological processes. Currently, NO has garnered significant interest as an antibacterial agent due to its capability to eradicate bacteria, disrupt biofilms, and facilitate wound healing, all while circumventing the emergence of drug resistance. However, the inherently unstable characteristic of NO therapeutic gas renders the controlled administration of NO gases exceedingly challenging. Hence, in this review, the current challenge of bacterial infection is discussed; then it is briefly elucidated the antibacterial mechanism of NO and comprehensively delineate the recent advancements in stimulus-responsive NO delivery platforms, along with their merits, obstacles, and prospective avenues for clinical application. This review offers guidance for future advancements in NO-medicated anti-infection therapy is hoped.

Gas Therapy: Generating, Delivery, and Biomedical Applications

Oxygen (O2), nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H2S), and hydrogen (H2) with direct effects, and carbon dioxide (CO2) with complementary effects on the condition of various diseases are known as therapeutic gases. The targeted delivery and in situ generation of these therapeutic gases with controllable release at the site of disease has attracted attention to avoid the risk of gas poisoning and improve their performance in treating various diseases such as cancer therapy, cardiovascular therapy, bone tissue engineering, and wound healing. Stimuli-responsive gas-generating sources and delivery systems based on biomaterials that enable on-demand and controllable release are promising approaches for precise gas therapy. This work highlights current advances in the design and development of new approaches and systems to generate and deliver therapeutic gases at the site of disease with on-demand release behavior. The performance of the delivered gases in various biomedical applications is then discussed.

High-Entropy Ceramics Enhanced Droplet Electricity Generator for Energy Harvesting and Bacterial Detection

The droplet electricity generator (DEG) is a solid-liquid triboelectric nanogenerator with transistor-inspired bulk effect, which is regarded as an effective strategy for raindrop energy harvesting. However, further enhancement of DEG output voltage is necessary to enable its widespread applications. Here, high-entropy ceramics are integrated into the design of DEG intermediate layer for the first time, achieving a high output voltage of 525 V. High-entropy ceramics have colossal dielectric constant, which can help to reduce the triboelectric charge decay for DEG. Furthermore, the effect of factors on DEG output performance when employing high-entropy ceramics as the intermediate layer is extensively analyzed, and the underlying mechanisms and mathematical models are explored. Finally, the enhanced output voltage of DEG not only facilitates faster energy harvesting but also develops a novel method for rapid bacterial detection. This work successfully integrates high-entropy ceramics into DEG design, significantly enhances the output voltage, and offers a novel direction for DEG development.

NIR-Triggered Multifunctional NO Nanoplatform for Conquering Thermal Resistance in Biofilms

Photothermal treatment (PTT) has emerged as a promising avenue for biofilm elimination, yet its potential drawbacks, such as local hyperpyrexia and bacterial heat resistance, have posed challenges. To address these concerns, an innovative nanoplatform (Au@mSiO2-arg/ICG) is devised that integrates phototherapeutic and gas therapeutic functionalities. This multifaceted nanoplatform is composed of mesoporous silica-coated Au nanorods (Au@mSiO2), supplemented with l-arginine (l-arg) and indocyanine green (ICG), and is engineered for mild temperature PTT aimed at biofilm eradication. Au@mSiO2-arg/ICG nanoparticles (NPs) show excellent antibacterial effects through the generation of nitric oxide (NO) gas, heat, and reactive oxygen species (ROS) under 808 nm light irradiation. The ROS generated by ICG initiates a cascade reaction with l-arg, ultimately yielding NO gas molecules. This localized release of NO not only effectively curbs the expression of heat shock proteins 70 mitigating bacterial thermoresistance, but also reduces extracellular polymeric substance allowing better penetration of the therapeutic agents. Furthermore, this nanoplatform achieves an outstanding biofilm elimination rate of over 99% in an abscess model under 808 nm light irradiation (0.8 W·cm-2), thereby establishing its potential as a dependable strategy for NO-enhanced mild PTT and antibacterial photodynamic therapy (aPDT) in clinical settings.

Self-Sulfhydrated, Nitro-Fixed Albumin Nanoparticles as a Potent Therapeutic Agent for the Treatment of Acute Liver Injury

Exogenous polysulfhydryls (R-SH) supplementation and nitric oxide (NO) gas molecules delivery provide essential antioxidant buffering pool components and anti-inflammatory species in cellular defense against injury, respectively. Herein, the intermolecular disulfide bonds in bovine serum albumin (BSA) molecules were reductively cleaved under native and mild conditions to expose multiple sulfhydryl groups (BSA-SH), then sulfhydryl-nitrosylated (R-SNO), and nanoprecipitated to form injectable self-sulfhydrated, nitro-fixed albumin nanoparticles (BSA-SNO NPs), allowing albumin to act as a NO donor reservoir and multiple sulfhydryl group transporter while also preventing unfavorable oxidation and self-cross-linking of polysulfhydryl groups. In two mouse models of ischemia/reperfusion-induced and endotoxin-induced acute liver injury (ALI), a single low dosage of BSA-SNO NPs (S-nitrosothiols: 4 μmol·kg-1) effectively attenuated oxidative stress and systemic inflammation cascades in the upstream pathophysiology of disease progression, thus rescuing dying hepatocytes, regulating host defense, repairing microcirculation, and restoring liver function. By mechanistically upregulating the antioxidative signaling pathway (Nrf-2/HO-1/NOQ1) and inhibiting the inflammatory cytokine storm (NF-κB/p-IκBα/TNF-α/IL-β), BSA-SNO NPs blocked the initiation of the mitochondrial apoptotic signaling pathway (Cyto C/Bcl-2 family/caspase-3) and downregulated the cell pyroptosis pathway (NLRP3/ASC/IL-1β), resulting in an increased survival rate from 26.7 to 73.3%. This self-sulfhydrated, nitro-fixed functionalized BSA nanoformulation proposes a potential drug-free treatment strategy for ALI.

Application of Non-Pharmacologic Therapy in Hair Loss Treatment and Hair Regrowth

Purpose

Alopecia significantly affects the appearance and psychology of patients, and pharmacological therapies and hair transplantation are the main treatments for alopecia, but both have limitations. This review aimed to summarize the non-pharmacological therapies that promote hair growth and regeneration.

Patients and Methods

This is a non-systematic review. Multiple databases was searched with relevant data published between 1997 and 2024. Searching and screening followed the PRISMA guidelines.

Results

Novel therapeutic modalities, such as gas molecules, platelet-rich plasma, laser, and microneedling, can change the microenvironment of hair follicles, activate hair follicle stem cells, and promote hair growth and regeneration.

Conclusion

This paper reviews research on the application of non-pharmacological therapies in alopecia treatment and hair regeneration, with a view to providing an important basis for future research on alopecia treatment and the postoperative treatment of patients after hair transplantation.

Naphthalimide-based light-induced nitric oxide-releasing nanoscale vesicles with visual detection and cytotoxicity studies

The therapeutic potential of nitric oxide (NO) has been receiving increasing interest, but achieving controlled release under physiological conditions remains challenging. Herein, we report a colorimetric and fluorescence responsive naphthalimide-based amphiphilic N-nitroso-based NO donor (Nap-NO) and its NO-releasing behavior. Nap-NO was incorporated into phospholipid nanovesicles to make it biocompatible and water-soluble. Light-induced NO-releasing behavior and emission changes were monitored via UV-vis, colorimetric detection, IR (Infrared) spectroscopy studies, and Griess assay. The Nap-NO donor within the 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)-cholesterol vesicles exhibited a slower release rate, with a significantly extended half-life as compared to the only DOPC vesicles. Incorporating the Nap-NO into alginate hydrogel beads enables a simple, visual detection of NO release through color and emission changes. Bioimaging experiments within the HCT cell line reveal the use of the new NO donor for fluorescent bio-imaging and clearly illustrate their proficiency in killing cancer cells upon NO delivery in the presence of light.

Evaluation of Anticancer Activity of Nucleoside-Nitric Oxide Photo-Donor Hybrids

Herein, we report the synthesis of a new hybrid compound based on a 2'-deoxyuridine nucleoside conjugated with a NO photo-donor moiety (dU-t-NO) via CuAAC click chemistry. Hybrid dU-t-NO, as well as two previously reported 2'-deoxyadenosine based hybrids (dAdo-S-NO and dAdo-t-NO), were evaluated for their cytotoxic and cytostatic activities in selected cancer cell lines. dAdo-S-NO and dAdo-t-NO hybrids displayed higher activity with respect to dU-t-NO. All hybrids showed effective release of NO in the micromolar range. The photochemical behavior of the newly reported hybrid, dU-t-NO, was studied in the RKO colon carcinoma cell line, whereas the dAdo-t-NO hybrid was tested in both colon carcinoma RKO and hepatocarcinoma Hep 3B2.1-7 cell lines to evaluate the potential effect of NO released upon irradiation on cell viability. A customized irradiation apparatus for in vitro experiments was also designed.

Flavor-switchable scaffold for cultured meat with enhanced aromatic properties

Cultured meat is emerging as a new type of food that can provide animal protein in a sustainable way. Many previous studies employed various types of scaffolds to develop cultured meat with similar properties to slaughtered meat. However, important properties such as flavor were not discussed, even though they determine the quality of food. Flavor characteristics vary dramatically depending on the amount and types of amino acids and sugars that produce volatile compounds through the Maillard reaction upon cooking. In this study, a flavor-switchable scaffold is developed to release meaty flavor compounds only upon cooking temperature mimicking the Maillard reaction of slaughtered meat. By introducing a switchable flavor compound (SFC) into a gelatin-based hydrogel, we fabricate a functional scaffold that can enhance the aromatic properties of cultured meat. The temperature-responsive SFC stably remains in the scaffold during the cell culture period and can be released at the cooking temperature. Surprisingly, cultured meat fabricated with this flavor-switchable scaffold exhibits a flavor pattern similar to that of beef. This research suggests a strategy to develop cultured meat with enhanced sensorial characteristics by developing a functional scaffold which can mimic the natural cooking flavors of conventional meat.

Photothermal-controlled NO-releasing Nanogels reverse epithelial-mesenchymal transition and restore immune surveillance against cancer metastasis

Metastasis leads to high mortality among cancer patients. It is a complex, multi-step biological process that involves the dissemination of cancer cells from the primary tumor and their systemic spread throughout the body, primarily through the epithelial-mesenchymal transition (EMT) program and immune evasion mechanisms. It presents a challenge in how to comprehensively treat metastatic cancer cells throughout the entire stage of the metastatic cascade using a simple system. Here, we fabricate a nanogel (HNO-NG) by covalently crosslinking a macromolecular nitric oxide (NO) donor with a photothermal IR780 iodide-containing hyaluronic acid derivative via a click reaction. This enables stable storage and tumor-targeted, photothermia-triggered release of NO to combat tumor metastasis throughout all stages. Upon laser irradiation (HNO-NG+L), the surge in NO production within tumor cells impairs the NF-κB/Snail/RKIP signaling loop that promotes the EMT program through S-nitrosylation, thus inhibiting cell dissemination from the primary tumor. On the other hand, it induces immunogenic cell death (ICD) and thereby augments anti-tumor immunity, which is crucial for killing both the primary tumor and systemically distributed tumor cells. Therefore, HNO-NG+L, by fully leveraging EMT reversal, ICD induction, and the lethal effect of NO, achieved impressive eradication of the primary tumor and significant prevention of lung metastasis in a mouse model of orthotropic 4T1 breast tumor that spontaneously metastasizes to the lungs, extending the NO-based therapeutic approach against tumor metastasis.

Effects of Nitrosyl Iron Complexes with Thiol, Phosphate, and Thiosulfate Ligands on Hemoglobin

Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4-) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4-. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4- efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems.

Fabrication and Optimization of Poly(ε-caprolactone) Microspheres Loaded with S-Nitroso-N-Acetylpenicillamine for Nitric Oxide Delivery

Heart disease is one of the leading causes of death in the United States and throughout the world. While there are different techniques for reducing or preventing the impact of heart disease, nitric oxide (NO) is administered as nitroglycerin for reversing angina or chest pain. Unfortunately, due to its gaseous and short-lived half-life, NO can be difficult to study or even administer. Therefore, controlled delivery of NO is desirable for therapeutic use. In the current study, the goal was to fabricate NO-releasing microspheres (MSs) using a donor molecule, S-Nitroso-N-Acetyl penicillamine, (SNAP), and encapsulating it in poly(ε-caprolactone) (PCL) using a single-emulsion technique that can provide sustained delivery of NO to cells over time without posing any toxicity risks. Optimization of the fabrication process was performed by varying the duration of homogenization (5, 10, and 20 min) and its effect on entrapment efficiency and size. The optimized SNAP-MS had an entrapment efficiency of ˃50%. Furthermore, we developed a modified method for NO detection by using NO microsensors to detect the NO release from SNAP-MSs in real time, showing sustained release behavior. The fabricated SNAP-MSs were tested for biocompatibility with HUVECs (human umbilical vein endothelial cells), which were found to be biocompatible. Lastly, we tested the effect of controlled NO delivery to human induced pluripotent stem-derived cardiomyocytes (hiPSC-CMs) via SNAP-MSs, which showed a significant improvement in the electrophysiological parameters and alleviated anoxic stress.

Photoactivated Gas-Generating Nanocontrast Agents for Long-Term Ultrasonic Imaging-Guided Combined Therapy of Tumors

To date, long-term and continuous ultrasonic imaging for guiding the puncture biopsy remains a challenge. In order to address this issue, a multimodality imaging and therapeutic method was developed in the present study to facilitate long-term ultrasonic and fluorescence imaging-guided precision diagnosis and combined therapy of tumors. In this regard, certain types of photoactivated gas-generating nanocontrast agents (PGNAs), capable of exhibiting both ultrasonic and fluorescence imaging ability along with photothermal and sonodynamic function, were designed and fabricated. The advantages of these fabricated PGNAs were then utilized against tumors in vivo, and high therapeutic efficacy was achieved through long-term ultrasonic imaging-guided treatment. In particular, the as-prepared multifunctional PGNAs were applied successfully for the fluorescence-based determination of patient tumor samples collected through puncture biopsy in clinics, and superior performance was observed compared to the clinically used SonoVue contrast agents that are incapable of specifically distinguishing the tumor in ex vivo tissues.

Stepwise Nitric Oxide Release and Antibacterial Activity of a Nitric Oxide Photodonor Hosted within Cyclodextrin Branched Polymer Nanocarriers

A hydrophobic nitric oxide (NO) photodonor integrating both nitroso and nitro functionalities within its chromophoric skeleton has been synthesized. Excitation of this compound with blue light triggers the release of two NO molecules from the nitroso and the nitro functionalities via a stepwise mechanism. Encapsulation of the NO photodonor within biocompatible neutral, cationic, and anionic β-cyclodextrin branched polymers as suitable carriers leads to supramolecular nanoassemblies, which exhibit the same nature of the photochemical processes but NO photorelease performances enhanced by about 1 order of magnitude when compared with the free guest. Antibacterial tests carried out with methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii demonstrate an effective antibacterial activity exclusively under light activation and point out a differentiated role of the polymeric nanocarriers in determining the outcome of the antibacterial photodynamic action.

Accurate Spatio-Temporal Delivery of Nitric Oxide Facilitates the Programmable Repair of Avascular Dense Connective Tissues Injury

Avascular dense connective tissues (e.g., the annulus fibrosus (AF) rupture, the meniscus tear, and tendons and ligaments injury) repair remains a challenge due to the "biological barrier" that hinders traditional drug permeation and limits self-healing of the injured tissue. Here, accurate delivery of nitric oxide (NO) to penetrate the "AF biological barrier" is achieved thereby enabling programmable AF repair. NO-loaded BioMOFs are synthesized and mixed in a modified polyvinyl alcohol and PCL-composited electrospun fiber membrane with excellent reactive oxygen species-responsive capability (LN@PM). The results show that LN@PM could respond to the high oxidative stress environment at the injured tissue and realize continuous and substantial NO release. Based on low molecular weight and lipophilicity, NO could penetrate through the "biological barrier" for accurate AF drug delivery. Moreover, the dynamic characteristics of the LN@PM reaction can be matched with the pathological microenvironment to initiate programmable tissue repair including sequential remodeling microenvironment, reprogramming the immune environment, and finally promoting tissue regeneration. This tailored programmable treatment strategy that matches the pathological repair process significantly repairs AF, ultimately alleviating intervertebral disc degeneration. This study highlights a promising approach for avascular dense connective tissue treatment through intelligent NO release, effectively overcoming "AF biological barriers" and programmable treatment.

Targeted delivery of anti-osteoporosis therapy: Bisphosphonate-modified nanosystems and composites

Osteoporosis (OP) constitutes a significant health concern that profoundly affects individuals' quality of life. Bisphosphonates, conventional pharmaceuticals widely employed in OP treatment, encounter limitations related to inadequate drug targeting and a short effective duration, thereby compromising their clinical efficacy. The burgeoning field of nanotechnology has witnessed the development and application of diverse functional nanosystems designed for OP treatment. Owing to the bone tissue affinity of bisphosphonates, these nanosystems are modified to address shortcomings associated with traditional drug delivery. In this review, we explore the potential of bisphosphonate-modified nanosystems as a promising strategy for addressing osteoporotic conditions. With functional modification, these nanosystems exhibit a targeted and reversible effect on osteoporotic remodeling, presenting a promising solution to enhance precision in drug delivery. The synthesis methods, physicochemical properties, and in vitro/in vivo performance of bisphosphonate-modified nanosystems are comprehensively examined in this review. Through a thorough analysis of recent advances and accomplishments in this field, we aim to provide insights into the potential applications and future directions of bisphosphonate-modified nanosystems for targeted and reversible osteoporotic remodeling.

Chemodynamic PtMn Nanocubes for Effective Photothermal ROS Storm a Key Anti-Tumor Therapy in-vivo

Background

Chemodynamic therapy (CDT) is a new treatment approach that is triggered by endogenous stimuli in specific intracellular conditions for generating hydroxyl radicals. However, the efficiency of CDT is severely limited by Fenton reaction agents and harsh reaction conditions.

Methods

Bimetallic PtMn nanocubes were rationally designed and simply synthesized through a one-step high-temperature pyrolysis process by controlling both the nucleation process and the subsequent crystal growth stage. The polyethylene glycol was modified to enhance biocompatibility.

Results

Benefiting from the alloying of Pt nanocubes with Mn doping, the structure of the electron cloud has changed, resulting in different degrees of the shift in electron binding energy, resulting in the increasing of Fenton reaction activity. The PtMn nanocubes could catalyze endogenous hydrogen peroxide to toxic hydroxyl radicals in mild acid. Meanwhile, the intrinsic glutathione (GSH) depletion activity of PtMn nanocubes consumed GSH with the assistance of Mn3+/Mn2+. Upon 808 nm laser irradiation, mild temperature due to the surface plasmon resonance effect of Pt metal can also enhance the Fenton reaction.

Conclusion

PtMn nanocubes can not only destroy the antioxidant system via efficient reactive oxygen species generation and continuous GSH consumption but also propose the photothermal effect of noble metal for enhanced Fenton reaction activity.

Applications of nitric oxide-releasing nanomaterials in dermatology: Skin infections and wound healing

Nitric oxide (NO) is produced in most cells in the skin and is an important regulator of essential cutaneous functions, including responses to UV irradiation, microbial defense, wound healing, melanogenesis and epidermal permeability barrier homeostasis. Harnessing the physiological activities of NO for therapeutic use is difficult because the molecule is highly reactive and unstable. A variety of exogenous NO delivery platforms have been developed and evaluated; however, they have limited clinical applications in dermatology due to instability and poor cutaneous penetration. NO-releasing nanomaterials overcome these limitations, providing targeted tissue delivery, and sustained and controlled NO release. This review provides a comprehensive and up-to-date evaluation of the use of NO-releasing nanomaterials in dermatology for the treatment of skin and soft tissue infections and wound healing.

S-Nitrosylated CuS Hybrid Hydrogel Patches with Robust Antibacterial and Repair-Promoting Activity for Infected Wound Healing

Development of wound dressing with robust antibacterial and repair-promoting activity has always been an urgent biomedical task during the past years. The therapeutic effect of current hydrogel dressings containing single bioactive agent like nanoparticle or gas is still unsatisfactory for the treatment of infected wound. Herein, a CuS/NO co-loaded hydrogel (CuS/NO Gel) is proposed, which is constructed by sequential polymerization, reduction, and S-nitrosylation of CuS hybrid hydrogel with disulfide bonds. These CuS/NO Gel patches show good mechanical stability, high photothermal activity and excellent biocompatibility. When being applied to treat infected wound, CuS/NO Gel can not only eliminate infection effectively by the synergistic effect of mild photothermal heating and boosted NO release in infection phase, but also promote vascularization and collagen deposition due to the synchronous supply of Cu ion nutrients and low concentration NO signaling molecules in wound repair phase. Compared to hydrogel dressings with individual active agent (CuS Gel or NO Gel), CuS/NO Gel exhibits better antibacterial and repair-promoting activity both in vitro and in vivo. Therefore, this CuS/NO Gel holds great promise in the future clinical treatment against infected wound.

Collaborative Optimization Design of Self-Powered Sterilizer with Highly Efficient Synergistic Antibacterial Effect

The development of self-powered sterilizers has garnered significant attention in the scientific and engineering fields. However, there remains an urgent need to improve their sterilization efficiency. In this study, we present a self-powered sterilizer with superior antibacterial capability by maximizing the utilization of breakdown discharge generated by a soft-contact freestanding rotary triboelectric nanogenerator (FR-TENG). To achieve this, a collaborative optimization strategy is proposed, encompassing the structural design of the FR-TENG, the implementation of double voltage rectification, and manipulation of the gaseous phase. Through a comprehensive analysis of antibacterial rates and microscopic images, the effectiveness of the self-powered sterilizer against various types of bacteria, including Gram-positive and Gram-negative species, as well as mixed bacteria in natural seawater, is demonstrated. Further investigations into bacterial morphologies and solution compositions reveal that the synergistic effect between electroporation and the generation of reactive oxygen/nitrogen species contributes to efficient sterilization. Additionally, controlled trials and molecular dynamics simulations are conducted to quantitatively elucidate the synergistic antibacterial effect between electroporation and reactive oxygen/nitrogen species. This study highlights the effectiveness of the collaborative optimization strategy in enhancing the sterilization efficiency of self-powered sterilizers while providing valuable insights into the synergistic antibacterial mechanisms of physical and chemical sterilization.

Prepared MW-Immunosensitizers Precisely Release NO to Downregulate HIF-1α Expression and Enhance Immunogenic Cell Death

Microwave thermotherapy (MWTT) has limited its application in the clinic due to its high rate of metastasis and recurrence after treatment. Nitric oxide (NO) is a gaseous molecule that can address the high metastasis and recurrence rates after MWTT by increasing thermal sensitivity, down-regulating the expression of hypoxia-inducible factor-1 (HIF-1), and inducing the immunogenic cell death (ICD). Therefore, GaMOF-Arg is designed, a gallium-based organic skeleton material derivative loaded with L-arginine (L-Arg), and coupled the mitochondria-targeting drug of triphenylphosphine (TPP) on its surface to obtain GaMOF-Arg-TPP (GAT) MW-immunosensitizers. When GAT MW-immunosensitizers are introduced into mice through the tail vein, reactive oxygen species (ROS) are generated and L-Arg is released under MW action. Then, L-Arg reacts with ROS to generate NO, which not only downregulates HIF-1 expression to improve tumor hypoxia exacerbated by MW, but also enhances immune responses by augment calreticulin (CRT) exposure, high mobility group box 1 (HMGB1) release, and T-cell proliferation to achieve prevention of tumor metastasis and recurrence. In addition, NO can induce mitochondria damage to increase their sensitivity to MWTT. This study provides a unique insight into the use of metal-organic framework MW-immunosensitizers to enhance tumor therapy and offers a new way to treat cancer efficiently.

Harnessing anti-inflammatory pathways and macrophage nano delivery to treat inflammatory and fibrotic disorders

Targeting specific organs and cell types using nanotechnology and sophisticated delivery methods has been at the forefront of applicative biomedical sciences lately. Macrophages are an appealing target for immunomodulation by nanodelivery as they are heavily involved in various aspects of many diseases and are highly plastic in their nature. Their continuum of functional "polarization" states has been a research focus for many years yielding a profound understanding of various aspects of these cells. The ability of monocyte-derived macrophages to metamorphose from pro-inflammatory to reparative and consequently to pro-resolving effectors has raised significant interest in its therapeutic potential. Here, we briefly survey macrophages' ontogeny and various polarization phenotypes, highlighting their function in the inflammation-resolution shift. We review their inducing mediators, signaling pathways, and biological programs with emphasis on the nucleic acid sensing-IFN-I axis. We also portray the polarization spectrum of macrophages and the characteristics of their transition between different subtypes. Finally, we highlighted different current drug delivery methods for targeting macrophages with emphasis on nanotargeting that might lead to breakthroughs in the treatment of wound healing, bone regeneration, autoimmune, and fibrotic diseases.

pH/GSH dual responsive nanosystem for nitric oxide generation enhanced type I photodynamic therapy

Tumor hypoxia diminishes the effectiveness of traditional type II photodynamic therapy (PDT) due to oxygen consumption. Type I PDT, which can operate independently of oxygen, is a viable option for treating hypoxic tumors. In this study, we have designed and synthesized JSK@PEG-IR820 NPs that are responsive to the tumor microenvironment (TME) to enhance type I PDT through glutathione (GSH) depletion. Our approach aims to expand the sources of therapeutic benefits by promoting the generation of superoxide radicals (O2-.) while minimizing their consumption. The diisopropyl group within PEG-IR820 serves a dual purpose: it functions as a pH sensor for the disassembly of the NPs to release JSK and enhances intermolecular electron transfer to IR820, facilitating efficient O2-. generation. Simultaneously, the release of JSK leads to GSH depletion, resulting in the generation of nitric oxide (NO). This, in turn, contributes to the formation of highly cytotoxic peroxynitrite (ONOO-.), thereby enhancing the therapeutic efficacy of these NPs. NIR-II fluorescence imaging guided therapy has achieved successful tumor eradication with the assistance of laser therapy.

Nanoplatform-based strategies for enhancing the lethality of current antitumor PDT

Photodynamic therapy (PDT) exhibits great application prospects in future clinical oncology due to its spatiotemporal controllability and good biosafety. However, the antitumor efficacy of PDT is seriously hindered by many factors, including tumor hypoxia, limited light penetration ability, and strong defense mechanisms of tumors. Considering that it is difficult to completely solve the first two problems, enhancing the lethality of antitumor PDT has become a good idea to extend its clinical application. Herein, we summarize the nanoplatform-involved strategies to effectively amplify the tumoricidal capability of current PDT and then discuss the present bottlenecks and prospects of the nanoplatform-based PDT sensitization strategies in tumor therapy. We hope this review will provide some references for others to design high-performance PDT nanoplatforms for tumor therapy.

Nitric oxide-scavenging hyaluronic acid nanoparticles for osteoarthritis treatment

Osteoarthritis (OA) is a degenerative arthritis disease marked by inflammation, pain, and cartilage deterioration. Elevated nitric oxide (NO) levels play a pivotal role in mediating OA-related inflammation and are found in abundance within OA joints. This study introduces a NO-scavenging hyaluronic acid conjugate (HA-NSc) bearing both lubrication and anti-inflammatory properties for the treatment of osteoarthritis. For this, a derivative of o-phenylenediamine (o-PD) with good NO-scavenging capability (NSc) is designed, synthesized and chemically conjugated to HA. Owing to the amphiphilicity, this as-synthesized HA-NSc conjugate formed self-assembled nanoparticles (HA-NSc NPs) under aqueous conditions. When treated with activated murine macrophage RAW 264.7 cells that produce high levels of NO, these nanoparticles effectively reduced intracellular NO concentrations and inflammatory cytokines. In an OA animal model, the HA-NSc NPs significantly alleviated pain and diminished the cartilage damage due to the combined lubricating property of HA and NO-scavenging ability of NSc. Overall, the results from the study suggest HA-NSc NPs as a dual-action therapeutic agent for the treatment of OA by alleviating pain, inflammation, and joint damage, and also positioning the HA-NSc NPs as a promising candidate for innovative treatment of OA.

JS-K Combined with a Melanin-Based Theranostic Agent: A Novel Sequential Delivery Strategy to Enhance the Near-Infrared Fluorescence Imaging of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a 5 year survival rate less than 12%. This malignancy is closely related to the unique tumor microenvironment (TME), which is characterized by a hypovascular and hyperdense extracellular matrix, making it difficult for drugs to permeate the tumor center. Near-infrared fluorescence (NIRF) imaging, which has high sensitivity and resolution, may improve the survival rate of PDAC patients. In this study, we first used JS-K (O2-(2,4-dinitrophenyl) 1-[(4-ethoxycarbonyl) piperazine-1-yl] diazene-1-ium-1,2-diolate) to specifically dilate blood vessels within the TME of PDAC patients and subsequently injected IR820-PEG-MNPs (IPM NPs) to diagnose and treat orthotopic PDAC. We found that JS-K promoted the accumulation of IPM NPs in orthotopic Pan02 tumor-bearing mice and was able to increase the tumor signal-to-background ratio (SBR) in the orthotopic PDAC area by 41.5%. In addition, surgical navigation in orthotopic Pan02 tumor-bearing mice and complete tumor resection based on fluorescence imaging were achieved with a detection sensitivity of 81.0%. Moreover, we verified the feasibility of the combination of laparoscopy and photothermal ablation (PTA) for the treatment of PDAC. Finally, we demonstrated that IPM NPs had greater affinity for human PDAC tissues than for normal pancreatic tissues ex vivo, preliminarily highlighting the potential for clinical translation of these NPs. In conclusion, we developed and validated a novel sequential delivery strategy that promotes the accumulation of nanoagents in the tumor area and can be used for the diagnosis and treatment of PDAC.

Photodynamic Therapy for Eye, Ear, Laryngeal Area, and Nasal and Oral Cavity Diseases: A Review

Photodynamic therapy (PDT) has emerged as a promising modality for the treatment of various diseases. This non-invasive approach utilizes photosensitizing agents and light to selectively target and destroy abnormal cells, providing a valuable alternative to traditional treatments. Research studies have explored the application of PDT in different areas of the head. Research is focusing on a growing number of new developments and treatments for cancer. One of these methods is PDT. Photodynamic therapy is now a revolutionary, progressive method of cancer therapy. A very important feature of PDT is that cells cannot become immune to singlet oxygen. With this therapy, patients can avoid lengthy and costly surgeries. PDT therapy is referred to as a safe and highly selective therapy. These studies collectively highlight the potential of PDT as a valuable therapeutic option in treating the head area. As research in this field progresses, PDT may become increasingly integrated into the clinical management of these conditions, offering a balance between effectiveness and minimal invasiveness.

Rational designed Fe-ZIFs@CoP nanoplatforms for photothermal-enhanced ROS-mediated tumor therapy

Metal-organic frameworks (MOFs), with biocompatible and bio-friendly properties, exhibit intriguing potential for the drug delivery system and imaging-guided synergistic cancer theranostics. Even though tremendous attention has been attracted on MOFs-based therapeutics, which play a crucial role in therapeutic drugs, gene, and biomedical agents delivery of cancer therapy, they are often explored as simple nanocarriers without further "intelligent" functions. Herein, Fe-doped MOFs with CoP nanoparticles loading were rationally designed and synthesized for photothermal enhanced reactive oxygen species (ROS)-mediated treatment. Fe-ZIFs@CoP could generate efficient ROS through the Fenton reaction while depleting glutathione for amplifying oxidative stress. Particularly, due to the photothermal effect of Fe-ZIFs@CoP, the hyperthermia generated by as-synthesized Fe-ZIFs@CoP facilitated the advanced performance of the Fenton effect for a high amount of ROS generation. The promising "all-in-one" synergistic MOFs platform herein reported provides some prospects for future directions in this area.

Engineered Multifunctional Zinc-Organic Framework-Based Aggregation-Induced Emission Nanozyme for Accelerating Spinal Cord Injury Recovery

Functional recovery following a spinal cord injury (SCI) is challenging. Traditional drug therapies focus on the suppression of immune responses; however, strategies for alleviating oxidative stress are lacking. Herein, we developed the zinc-organic framework (Zn@MOF)-based aggregation-induced emission-active nanozymes for accelerating recovery following SCI. A multifunctional Zn@MOF was modified with the aggregation-induced emission-active molecule 2-(4-azidobutyl)-6-(phenyl(4-(1,2,2-triphenylvinyl)phenyl)amino)-1H-phenalene-1,3-dione via a bioorthogonal reaction, and the resulting nanozymes were denoted as Zn@MOF-TPD. These nanozymes gradually released gallic acid and zinc ions (Zn2+) at the SCI site. The released gallic acid, a scavenger of reactive oxygen species (ROS), promoted antioxidation and alleviated inflammation, re-establishing the balance between ROS production and the antioxidant defense system. The released Zn2+ ions inhibited the activity of matrix metalloproteinase 9 (MMP-9) to facilitate the regeneration of neurons via the ROS-mediated NF-κB pathway following secondary SCI. In addition, Zn@MOF-TPD protected neurons and myelin sheaths against trauma, inhibited glial scar formation, and promoted the proliferation and differentiation of neural stem cells, thereby facilitating the repair of neurons and injured spinal cord tissue and promoting functional recovery in rats with contusive SCI. Altogether, this study suggests that Zn@MOF-TPD nanozymes possess a potential for alleviating oxidative stress-mediated pathophysiological damage and promoting motor recovery following SCI.

A Single-Component Dual Donor Enables Ultrasound-Triggered Co-release of Carbon Monoxide and Hydrogen Sulfide

The development of dual gasotransmitter donors can not only provide robust tools to investigate their subtle interplay under pathophysiological conditions but also optimize therapeutic efficacy. While conventional strategies are heavily dependent on multicomponent donors, we herein report an ultrasound-responsive water-soluble copolymer (PSHF) capable of releasing carbon monoxide (CO) and hydrogen sulfide (H2 S) based on single-component sulfur-substituted 3-hydroxyflavone (SHF) derivatives. Interestingly, sulfur substitution can not only greatly improve the ultrasound sensitivity but also enable the co-release of CO/H2 S under mild ultrasound irradiation. The co-release of CO/H2 S gasotransmitters exerts a bactericidal effect against Staphylococcus aureus and demonstrates anti-inflammatory activity in lipopolysaccharide-challenged macrophages. Moreover, the excellent tissue penetration of ultrasound irradiation enables the local release of CO/H2 S in the joints of septic arthritis rats, exhibiting superior therapeutic efficacy without the need for any antibiotics.

All-in-one HN@Cu-MOF nanoparticles with enhanced reactive oxygen species generation and GSH depletion for effective tumor treatment

Non-invasive cancer therapies, especially those based on reactive oxygen species, including photodynamic therapy (PDT), have gained much interest. As emerging photodynamic nanocarriers, metal-organic frameworks (MOFs) based on porphyrin can release reactive oxygen species (ROS) to destroy cancer cells. However, due to the inefficient production of ROS by photosensitizers and the over-expression of glutathione (GSH) in the tumor microenvironment (TME), their therapeutic effect is not satisfactory. Therefore, herein, we developed a multi-functional nanoparticle, HN@Cu-MOF, to enhance the efficacy of PDT. We combined chemical dynamic therapy (CDT) and nitric oxide (NO) therapy by initiating sensitization to PDT and cell apoptosis in the treatment of tumors. The Cu2+-doped MOF reacted with GSH to form Cu+, exhibiting a strong CDT ability to generate hydroxyl radicals (˙OH). The Cu-MOF was coated with HN, which is hyaluronic acid (HA) modified by a nitric oxide donor. HN can target tumor cells over-expressing the CD44 receptor and consume GSH in the cells to release NO. Both cell experiments and in vivo experiments showed an excellent tumor inhibitory effect upon the treatment. Overall, the HN@Cu-MOF nanoparticle-integrated NO gas therapy and CDT with PDT led to a significant enhancement in GSH consumption and a remarkable elevation in ROS production.

Functionalized MoS2-nanosheets with NIR-Triggered nitric oxide delivery and photothermal activities for synergistic antibacterial and regeneration-promoting therapy

Bacterial infection in skin and soft tissue has emerged as a critical concern. Overreliance on antibiotic therapy has led to numerous challenges, including the emergence of multidrug-resistant bacteria and adverse drug reactions. It is imperative to develop non-antibiotic treatment strategies that not only exhibit potent antibacterial properties but also promote rapid wound healing and demonstrate biocompatibility. Herein, a novel multimodal synergistic antibacterial system (SNO-CS@MoS2) was developed. This system employs easily surface-modified thin-layer MoS2 as photothermal agents and loaded with S-nitrosothiol-modified chitosan (SNO-CS) via electrostatic interactions, thus realizing the combination of NO gas therapy and photothermal therapy (PTT). Furthermore, this surface modification renders SNO-CS@MoS2 highly stable and capable of binding with bacteria. Through PTT's thermal energy, SNO-CS@MoS2 rapidly generates massive NO, collaborating with PTT to achieve antibacterial effects. This synergistic therapy can swiftly disrupt the bacterial membrane, causing protein leakage and ATP synthesis function damage, ultimately eliminating bacteria. Notably, after effectively eliminating all bacteria, the residual SNO-CS@MoS2 can create trace NO to promote fibroblast migration, proliferation, and vascular regeneration, thereby accelerating wound healing. This study concluded that SNO-CS@MoS2, a novel multifunctional nanomaterial with outstanding antibacterial characteristics and potential to promote wound healing, has promising applications in infected soft tissue wound treatment.

Smart Magnetic Nanocarriers for Codelivery of Nitric Oxide and Doxorubicin for Enhanced Apoptosis in Cancer Cells

Extremely short half-life therapeutic molecule nitric oxide (NO) plays significant roles in the functioning of various physiological and pathological processes in the human body, whereas doxorubicin hydrochloride (DOX) is a clinically important anticancer drug widely used in cancer chemotherapy. Thus, the intracellular delivery of these therapeutic molecules is tremendously important to achieve their full potential. Herein, we report a novel approach for the development of highly water-dispersible magnetic nanocarriers for codelivery of NO and DOX. Primarily, bifunctional magnetic nanoparticles enriched with carboxyl and thiol groups were prepared by introducing cysteine onto the surface of citrate-functionalized Fe3O4 nanoparticles. DOX was electrostatically conjugated onto the surface of bifunctional nanoparticles via carboxyl moieties, whereas the thiol group was further nitrosated to provide NO-releasing molecules. The developed magnetic nanocarrier exhibited good aqueous colloidal stability, protein resistance behavior, and high encapsulation efficacy for NO (65.5%) and DOX (85%), as well as sustained release characteristics. Moreover, they showed superior cytotoxicity toward cancer (A549 and MCF-7) cells via apoptosis induction over normal (WI26VA4) cells. Specifically, we have developed magnetic nanocarriers having the capability of dual delivery of NO and DOX, which holds great potential for combinatorial cancer treatment.

Overview of the effects and mechanisms of NO and its donors on biofilms

Microbial biofilm is undoubtedly a challenging problem in the food industry. It is closely associated with human health and life, being difficult to remove and antibiotic resistance. Therefore, an alternate method to solve these problems is needed. Nitric oxide (NO) as an antimicrobial agent, has shown great potential to disrupt biofilms. However, the extremely short half-life of NO in vivo (2 s) has facilitated the development of relatively more stable NO donors. Recent studies reported that NO could permeate biofilms, causing damage to cellular biomacromolecules, inducing biofilm dispersion by quorum sensing (QS) pathway and reducing intracellular bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) levels, and significantly improving the bactericidal effect without drug resistance. In this review, biofilm hazards and formation processes are presented, and the characteristics and inhibitory effects of NO donors are carefully discussed, with an emphasis on the possible mechanisms of NO resistance to biofilms and some advanced approaches concerning the remediation of NO donor deficiencies. Moreover, the future perspectives, challenges, and limitations of NO donors were summarized comprehensively. On the whole, this review aims to provide the application prospects of NO and its donors in the food industry and to make reliable choices based on these available research results.

Tumor Microenvironment Activated Photoacoustic-Fluorescence Bimodal Nanoprobe for Precise Chemo-immunotherapy and Immune Response Tracing of Glioblastoma

Synergistic therapy strategy and prognostic monitoring of glioblastoma's immune response to treatment are crucial to optimize patient care and advance clinical outcomes. However, current systemic temozolomide (TMZ) chemotherapy and imaging methods for in vivo tracing of immune responses are inadequate. Herein, we report an all-in-one theranostic nanoprobe (PEG/αCD25-Cy7/TMZ) for precise chemotherapy and real-time immune response tracing of glioblastoma by photoacoustic-fluorescence imaging. The nanoprobe was loaded with TMZ and targeted regulatory T lymphocyte optical dye αCD25-Cy7 encapsulated by glutathione-responsive DSPE-SS-PEG2000. The results showed that the targeted efficiency of the nanoprobe to regulatory T lymphocytes is up to 92.3%. The activation of PEG/αCD25-Cy7/TMZ by glutathione enhanced the precise delivery of TMZ to the tumor microenvironment for local chemotherapy and monitored glioblastoma's boundary by photoacoustic-fluorescence imaging. Immunotherapy with indoleamine 2,3-dioxygenase inhibitors after chemotherapy could promote immunological responses and reduce regulatory T lymphocyte infiltration, which could improve the survival rate. Photoacoustic imaging has in real-time and noninvasively depicted the dynamic process of immune response on a micrometer scale, showing that the infiltration of regulatory T lymphocytes after chemotherapy was up-regulated and would down-regulate after IDO inhibitor treatment. This all-in-one theranostic strategy is a promising method for precisely delivering TMZ and long-term dynamically tracing regulatory T lymphocytes to evaluate the immune response in situ for accurate tumor chemo-immunotherapy.

Near-Infrared-Induced NO-Releasing Photothermal Adhesive Hydrogel with Enhanced Antibacterial Properties

Bacterial infection and the development of antibiotic-resistant bacteria have decreased the effectiveness of traditional antibiotic treatments for wound healing. The design of a multifunctional adhesive hydrogel with antibacterial activity, self-healing properties, and on-demand removability to promote wound healing is highly desirable. In this work, a photothermal cyclodextrin with a NO-releasing moiety has been incorporated within an oxidized sodium alginate conjugated polyacrylamide (OS@PA) hydrogel to get a photothermal NO-releasing GSNOCD-OS@PA hydrogel. Such a multifunctional hydrogel has the unique feature of combined antibacterial activity as a result of a controlled photothermal effect and NO gas release under an 808 near-infrared laser. Because of oxidized sodium alginate (OSA), the hydrogel matrix easily adheres to the skin under twisted and bent states. In vitro cytotoxicity analysis against 3T3 cells showed that the hydrogels OS@PA and GSNOCD-OS@PA are noncytotoxic under laser exposure. The temperature-induced NO release by GSNOCD-OS@PA reached 31.7 mg/L when irradiated with an 808 nm laser for 10 min. The combined photothermal therapy and NO release from GSNOCD-OS@PA effectively reduced viability of both Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) to 3 and 5%, respectively. Importantly, the phototherapeutic NO-releasing platform displayed effective fibroblast proliferation in a cell scratch assay.

GSH-Triggered/Photothermal-Enhanced H2S Signaling Molecule Release for Gas Therapy

Traditional treatment methods for tumors are inefficient and have severe side effects. At present, new therapeutic methods such as phototherapy, chemodynamic therapy, and gasodynamic therapy have been innovatively developed. High concentrations of hydrogen sulfide (H2S) gas exhibit cancer-suppressive effects. Herein, a Prussian blue-loaded tetra-sulfide modified dendritic mesoporous organosilica (PB@DMOS) was rationally constructed with glutathione (GSH)-triggered/photothermal-enhanced H2S signaling molecule release properties for gas therapy. The as-synthesized nanoplatform confined PB nanoparticles in the mesoporous structure of organosilica silica due to electrostatic adsorption. In the case of a GSH overexpressed tumor microenvironment, H2S gas was controllably released. And the temperature increases due to the photothermal effects of PB nanoparticles, further enhancing H2S release. At the same time, PB nanoparticles with excellent hydrogen peroxide catalytic performance also amplified the efficiency of tumor therapy. Thus, a collective nanoplatform with gas therapy/photothermal therapy/catalytic therapy functionalities shows potential promise in terms of efficient tumor therapy.