Hydrogen peroxide-activatable polymeric prodrug of curcumin for ultrasound imaging and therapy of acute liver failure

Dual-ROS Sensitive Moieties Conjugate Inhibits Curcumin Oxidative Degradation for Colitis Precise Therapy

Curcumin, a natural bioactive polyphenol with diverse molecular targets, is well known for its anti-oxidation and anti-inflammatory potential. However, curcumin exhibits low solubility (<1 µg mL-1), poor tissue-targeting ability, and rapid oxidative degradation, resulting in poor bioavailability and stability for inflammatory therapy. Here, poly(diselenide-oxalate-curcumin) nanoparticle (SeOC-NP) with dual-reactive oxygen species (ROS) sensitive chemical moieties (diselenide and peroxalate ester bonds) is fabricated by a one-step synthetic strategy. The results confirmed that dual-ROS sensitive chemical moieties endowed SeOC-NP with the ability of targeted delivery of curcumin and significantly suppress oxidative degradation of curcumin for high-efficiency inflammatory therapy. In detail, the degradation amount of curcumin for SeOC is about 4-fold lower than that of free curcumin in an oxidative microenvironment. As a result, SeOC-NP significantly enhanced the antioxidant activity and anti-inflammatory efficacy of curcumin in vitro analysis by scavenging intracellular ROS and suppressing the secretion of nitric oxide and pro-inflammatory cytokines. In mouse colitis models, orally administered SeOC-NP can remarkably alleviate the symptoms of IBD and maintain the homeostasis of gut microbiota. This work provided a simple and effective strategy to fabricate ROS-responsive micellar and enhance the oxidation stability of medicine for precise therapeutic inflammation.

Sequential Rocket-Mode Bioactivating Ticagrelor Prodrug Nanoplatform Combining Light-Switchable Diphtherin Transgene System for Breast Cancer Metastasis Inhibition

The increased risk of breast cancer metastasis is closely linked to the effects of platelets. Our previously light-switchable diphtheria toxin A fragment (DTA) gene system, known as the LightOn system, has demonstrated significant therapeutic potential; it lacks antimetastatic capabilities. In this study, we devised an innovative system by combining cell membrane fusion liposomes (CML) loaded with the light-switchable transgene DTA (pDTA) and a ticagrelor (Tig) prodrug. This innovative system, named the sequential rocket-mode bioactivating drug delivery system (pDTA-Tig@CML), aims to achieve targeted pDTA delivery while concurrently inhibiting platelet activity through the sequential release of Tig triggered by reactive oxygen species with the tumor microenvironment. In vitro investigations have indicated that pDTA-Tig@CML, with its ability to sequentially release Tig and pDTA, effectively suppresses platelet activity, resulting in improved therapeutic outcomes and the mitigation of platelet driven metastasis in breast cancer. Furthermore, pDTA-Tig@CML exhibits enhanced tumor aggregation and successfully restrains tumor growth and metastasis. It also reduces the levels of ADP, ATP, TGF-β, and P-selectin both in vitro and in vivo, underscoring the advantages of combining the bioactivating Tig prodrug nanoplatform with the LightOn system. Consequently, pDTA-Tig@CML emerges as a promising light-switchable DTA transgene system, offering a novel bioactivating prodrug platform for breast cancer treatment.

From liver fibrosis to hepatocarcinogenesis: Role of excessive liver H2O2 and targeting nanotherapeutics

Liver fibrosis and hepatocellular carcinoma (HCC) have been worldwide threats nowadays. Liver fibrosis is reversible in early stages but will develop precancerosis of HCC in cirrhotic stage. In pathological liver, excessive H₂O₂ is generated and accumulated, which impacts the functionality of hepatocytes, Kupffer cells (KCs) and hepatic stellate cells (HSCs), leading to genesis of fibrosis and HCC. H₂O₂ accumulation is associated with overproduction of superoxide anion (O₂^•−) and abolished antioxidant enzyme systems. Plenty of therapeutics focused on H₂O₂ have shown satisfactory effects against liver fibrosis or HCC in different ways. This review summarized the reasons of liver H₂O₂ accumulation, and the role of H₂O₂ in genesis of liver fibrosis and HCC. Additionally, nanotherapeutics targeting H₂O₂ were summarized for further consideration of antifibrotic or antitumor therapy.

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Liver fibrosis and HCC are closely related because ROS induced liver damage and inflammation, especially over-cumulated H₂O₂.

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Excess H₂O₂ diffusion in pathological liver was due to increased metabolic rate and diminished cellular antioxidant systems.

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Freely diffused H₂O₂ damaged liver-specific cells, thereby leading to fibrogenesis and hepatocarcinogenesis.

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Nanotherapeutics targeting H₂O₂ are summarized for treatment of liver fibrosis and HCC, and also challenges are proposed.

Hydrogen-Bonds Mediated Nanomedicine: Design, Synthesis and Applications

Among the various challenges in medicine, diagnosis, complete cure and healing of cancers remain difficult given the heterogeneity and complexity of such disease. Differing from conventional platforms with often unsatisfactory theranostic capabilities, the contribution of supramolecular interactions, such as hydrogen-bonds (H-bonds), to cancer nanotheranostics opens new perspectives for the design of biomedical materials, exhibiting remarkable properties and easier processability. Thanks to their dynamic characteristics, a feature generally observed for non-covalent interactions, H-bonding (macro)molecules can be used as supramolecular motifs for yielding drug- and diagnostic carriers that possess attractive features, arising from the combination of assembled nanoplatforms and the responsiveness of H-bonds. Thus H-bonded nanomedicine provides a rich toolbox that is useful to fulfill biomedical needs with unique advantages in early-stage diagnosis and therapy, demonstrating the promising potential in clinical translations and applications. We here summarize the design and synthetic routes towards H-bonded nanomedicines, focus on the growing understanding of the structure-function relationship for efficient cancer treatment. We propose a guidance for designing new H-bonded intelligent theranostic agents, to inspire more successful explorations of cancer nanotheranostics and finally to promote potential clinical translations. This article is protected by copyright. All rights reserved.

Engineered EGCG-Containing Biomimetic Nanoassemblies as Effective Delivery Platform for Enhanced Cancer Therapy

Nano-based immunotherapy of therapeutic biomolecules is attractive but tremendously hampered by the poor delivery efficiency. This study reports a novel delivery system of fluorinated-coordinative-epigallocatechin gallate (EGCG), referring as FEGCG/Zn, through the integration of fluorination and zinc ions (Zn²⁺ ) into EGCG. The robust therapeutics of FEGCG/Zn are measured in terms of the regulating effect on programmed cell death ligand 1 (PD-L1), the effective delivery of diverse biomolecules, and the hitchhiking ability using living cells. Taking small interfering RNA of PD-L1 (siPD-L1) and erythrocytes as an example, the fabricated biomimetic system achieves excellent siPD-L1 delivery and further improves siPD-L1 accumulation in tumors. Finally, the combination of FEGCG/Zn and siPD-L1 promotes antitumor immunotherapy through alleviation of T cells exhaustion by regulating PD-L1 expression in tumor cells. The results demonstrate that FEGCG/Zn substantially regulates PD-L1 expression and improves immune-biomolecule delivery by forming biomimetic nanoassemblies, offering a versatile platform for cancer immunotherapy.

Light-triggered Structural Modulation of Nanofibrous Meshes to Promote Deep Penetration of Cultured Cells

Although nanofibrous meshes are considered promising cultivation beds for maintaining cell differentiation, three-dimensional (3D) cultivation is not possible because their nanoporous structures impede cell infiltration. To facilitate transverse cell migration across nanofibrous meshes, we prepared electrospun nanofibers with structures that varied in response to red laser light. Polyoxalate (POX), composed of oxalate linkers and oligomeric caprolactone, was synthesized and electrospun into fibrous meshes with a photosensitizer (chlorin e6: Ce6). These meshes exhibited morphological and chemical changes upon laser irradiation, and mass erosion rates of the meshes were faster after laser irradiation. Cell cultivation on POX meshes revealed that red laser effectively facilitated traverse migration of the cells without affecting cell viability. We envision the use of light-triggered change of meshes to promote the migration of cells during 3D matrix cultivation. This article is protected by copyright. All rights reserved.

Harnessing reactive oxygen/nitrogen species and inflammation: Nanodrugs for liver injury

Overall, 12% of the global population (800 million) suffers from liver disease, which causes 2 million deaths every year. Liver injury involving characteristic reactive oxygen/nitrogen species (RONS) and inflammation plays a key role in progression of liver disease. As a key metabolic organ of the human body, the liver is susceptible to injury from various sources, including COVID-19 infection. Owing to unique structural features and functions of the liver, most current antioxidants and anti-inflammatory drugs are limited against liver injury. However, the characteristics of the liver could be utilized in the development of nanodrugs to achieve specific enrichment in the liver and consequently targeted treatment. Nanodrugs have shown significant potential in eliminating RONS and regulating inflammation, presenting an attractive therapeutic tool for liver disease through controlling liver injury. Therefore, the main aim of the current review is to provide a comprehensive summary of the latest developments contributing to our understanding of the mechanisms underlying nanodrugs in the treatment of liver injury via harnessing RONS and inflammation. Meanwhile, the prospects of nanodrugs for liver injury therapy are systematically discussed, which provides a sound platform for novel therapeutic insights and inspiration for design of nanodrugs to treat liver disease.

Nanotheranostics for the Management of Hepatic Ischemia-Reperfusion Injury

Hepatic ischemia-reperfusion injury (IRI), in which an insufficient oxygen supply followed by reperfusion leads to an inflammatory network and oxidative stress in disease tissue to cause cell death, always occurs after liver transplantations and sections. Although pharmacological treatments favorably prevent or protect the liver against experimental IRI, there have been few successes in clinical applications for patient benefits because of the incomprehension of complicated IRI-induced signaling events as well as short blood circulation time, poor solubility, and severe side reactions of most antioxidants and anti-inflammatory drugs. Nanomaterials can achieve targeted delivery and controllable release of contrast agents and therapeutic drugs in desired hepatic IRI regions for enhanced imaging sensitivity and improved therapeutic effects, emerging as novel alternative approaches for hepatic IRI diagnosis and therapy. In this review, the application of nanotechnology is summarized in the management of hepatic IRI, including nanomaterial-assisted hepatic IRI diagnosis, nanoparticulate systems-mediated remission of reactive oxygen species-induced tissue injury, and nanoparticle-based targeted drug delivery systems for the alleviation of IRI-related inflammation. The current challenges and future perspectives of these nanoenabled strategies for hepatic IRI treatment are also discussed.

Redox Responsive Copolyoxalate Smart Polymers for Inflammation and Other Aging-Associated Diseases

Polyoxalate (POx) and copolyoxalate (CPOx) smart polymers are topics of interest the field of inflammation. This is due to their drug delivery ability and their potential to target reactive oxygen species (ROS) and to accommodate small molecules such as curcumin, vanilline, and p-Hydroxybenzyl alcohol. Their biocompatibility, ultra-size tunable characteristics and bioimaging features are remarkable. In this review we discuss the genesis and concept of oxylate smart polymer-based particles and a few innovative systemic delivery methods that is designed to counteract the inflammation and other aging-associated diseases (AADs). First, we introduce the ROS and its role in human physiology. Second, we discuss the polymers and methods of incorporating small molecule in oxalate backbone and its drug delivery application. Finally, we revealed some novel proof of concepts which were proven effective in disease models and discussed the challenges of oxylate polymers.

Nanotechnology for Hepatocellular Carcinoma: From Surveillance, Diagnosis to Management

Hepatocellular carcinoma (HCC) remains the fourth leading cause of cancer-related death worldwide. However, the clinical diagnosis and treatment modalities are still relatively limited, which urgently require the development of new effective technologies. Recently, nanotechnology has gained extensive attention in HCC surveillance, imaging and pathological diagnosis, and therapeutic strategies. Typically, nanomedicines have been focused on early HCC diagnosis and precise treatment of advanced HCC, which has developed and improved a variety of new technologies and agents for future clinical practice. Furthermore, strategies of facilitating drug release and delivery in current treatment processes such as ablation, systematic therapy, transcatheter arterial chemoembolization, molecular targeted therapy, and immune-modulating therapy have also been studied widely. This review summarizes the recent advances in this area according to current clinical HCC guidelines: 1) Nanoparticle-based HCC surveillance; 2) Nanotechnology for HCC diagnosis; 3) Therapeutic advances for HCC Management; 4) Limitations of applications in nanotechnology for HCC; 5) Conclusions and perspectives. Although there are still many limitations and difficulties to overcome, the investigations of nanomedicines are believed to show potential applications in clinical practice.

Stimulus-cleavable chemistry in the field of controlled drug delivery

This review comprehensively summarises stimulus-cleavable linkers from various research areas and their cleavage mechanisms, thus provides an insightful guideline to extend their potential applications to controlled drug release from nanomaterials.

Applications of Nanobiomaterials in the Therapy and Imaging of Acute Liver Failure

This review focuses on the therapeutic mechanisms, targeting strategies of various nanomaterials in acute liver failure, and recent advances of diverse nanomaterials for acute liver failure therapy, diagnosis, and imaging. This review provides an outlook on the applications of nanomaterials, especially on the new horizons in acute liver failure therapy, and inspires broader interests across various disciplines. Acute liver failure (ALF), a fatal clinical disease featured with overwhelming hepatocyte necrosis, is a grand challenge in global health. However, a satisfactory therapeutic option for curing ALF is still absent, other than liver transplantation. Nanobiomaterials are currently being developed for the diagnosis and treatment of ALF. The liver can sequester most of nanoparticles from blood circulation, which becomes an intrinsic superiority for nanobiomaterials targeting hepatic diseases. Nanobiomaterials can enhance the bioavailability of free drugs, thereby significantly improving the therapeutic effects in ALF. Nanobiomaterials can also increase the liver accumulation of therapeutic agents and enable more effective targeting of the liver or specific liver cells. In addition, stimuli-responsive, optical, or magnetic nanomaterials exhibit great potential in the therapeutical, diagnostic, and imaging applications in ALF. Therefore, therapeutic agents in combination with nanobiomaterials increase the specificity of ALF therapy, diminish adverse systemic effects, and offer a multifunctional theranostic platform. Nanobiomaterial holds excellent significance and prospects in ALF theranostics. In this review, we summarize the therapeutic mechanisms and targeting strategies of various nanobiomaterials in ALF. We highlight recent developments of diverse nanomedicines for ALF therapy, diagnosis, and imaging. Furthermore, the challenges and future perspectives in the theranostics of ALF are also discussed.

Dexamethasone-loaded H2O2-activatable anti-inflammatory nanoparticles for on-demand therapy of inflammatory respiratory diseases

Asthma is a common airway inflammatory disorder, characterized by increased infiltration of leukocytes and bronchoconstriction. Dexamethasone (DEX) has been widely used in the treatment of allergic asthma. However, long-term and frequent use of DEX has side effects. We therefore reasoned that if drug carriers have intrinsic anti-inflammatory and anti-asthmatic activity and synergize with drug payloads, a low dose of DEX could exert sufficient therapeutic effects. In this study, we developed DEX-loaded H₂O₂-activatable boronate maltodextrin (DEX-BM) nanoparticles. DEX-BM nanoparticles released DEX in a H₂O₂-triggered manner and remarkably suppressed the expression of pro-inflammatory cytokines in activated macrophages and lung epithelial cells. In the studies of a murine allergic asthma model, DEX-BM nanoparticles (5 mg/kg) effectively inhibited the inflammatory cell infiltration and airway inflammation than equivalent DEX and BM nanoparticles without noticeable side effects. We anticipate that DEX-BM nanoparticles hold great potential as therapeutic agents for various airway inflammatory diseases.

Curcuminoids encapsulated liposome nanoparticles as a blue light emitting diode induced photodynamic therapeutic system for cancer treatment

Unlike normal cells, cancer cells mutate to thrive in exaggerated levels of reactive oxygen species (ROS). This potentially makes them more susceptible to small molecule-induced oxidative stress. The intracellular ROS increase in cancer cells is a potential area under investigation for the development of cancer therapeutics targeting cancer cells. Visible photons of 430-490 nm wavelengths from a blue-light emitting diode (BLED) encompass the visible region of the spectrum known to induce ROS in cancer cells. Curcuminoids (CUR) naturally occurring photosensitizers sensitized by the blue wavelength of the visible light, well known for its potent anti-inflammatory and anticancer activity. Poor solubility and bioavailability, of the compound of the small molecule CUR restrict the therapeutic potential and limits CUR to be used as a photosensitizer. Here, our research group reports the use of small molecules CUR, encapsulated in liposome nanocarriers (LIP-CUR) coupled with blue light-emitting diode (BLED) induced photodynamic therapy (BLED-PDT). In A549 cancer cells in vitro, LIP-CUR coupled with BLED initiated BLED-PDT and triggered ¹O₂, ultimately resulting in caspase-3 activated apoptotic cell death. The combination of a non-cytotoxic dose of small molecule CUR co-treated with BLED to trigger BLED-PDT could be translated and be developed as a novel strategy for the treatment of cancer.

H2O2-responsive nano-prodrug for podophyllotoxin delivery

The tumor microenvironment is different from that of normal tissue; therefore, the development of a prodrug that retains its efficacy in the tumor microenvironment can be useful in enhancing the anticancer properties of podophyllotoxin. An innovative podophyllotoxin prodrug (POD-PEG) was designed by linking podophyllotoxin to poly(ethylene glycol)(n) monomethacrylate with a H2O2-responsive oxalate ester bond. POD-PEG can self-assemble into stable nanoparticles (POD-PEG NPs). In vitro experiments demonstrated that the POD-PEG NPs can be activated by hydrogen peroxide resulting in podophyllotoxin release and are highly toxic against colon carcinoma CT26 cells. In vivo biodistribution studies demonstrate that PEGylated POD-PEG NPs are capable of prolonging blood circulation. Intravenous injection of POD-PEG NPs into CT26 tumor-bearing Balb/c mice resulted in a significantly enhanced therapeutic efficacy against tumors, with no significant systemic toxicity. Therefore, this H2O2-responsive prodrug delivery system exhibits good biosafety and provides a novel strategy for the development of drug delivery systems.

Recent Advances on Reactive Oxygen Species-Responsive Delivery and Diagnosis System

Reactive oxygen species (ROS) play crucial roles in biological metabolism and intercellular signaling. However, ROS level is dramatically elevated due to abnormal metabolism during multiple pathologies, including neurodegenerative diseases, diabetes, cancer, and premature aging. By taking advantage of the discrepancy of ROS levels between normal and diseased tissues, a variety of ROS-sensitive moieties or linkers have been developed to design ROS-responsive systems for the site-specific delivery of drugs and genes. In this review, we summarized the ROS-responsive chemical structures, mechanisms, and delivery systems, focusing on their current advances for precise drug/gene delivery. In particular, ROS-responsive nanocarriers, prodrugs, and supramolecular hydrogels are summarized in terms of their application for drug/gene delivery, and common strategies to elevate or diminish cellular ROS concentrations, as well as the recent development of ROS-related imaging probes were also discussed.