Search

Background: Epsin endocytic adaptor proteins are implicated in the progression of atherosclerosis; however, the underlying molecular mechanisms have not yet been fully defined. In this study, we determined how epsins enhance endothelial-to-mesenchymal transition (EndoMT) in atherosclerosis and assessed the efficacy of a therapeutic peptide in a preclinical model of this disease. Methods: Using single-cell RNA sequencing combined with molecular, cellular, and biochemical analyses, we investigated the role of epsins in stimulating EndoMT using knockout in Apoe −/− and lineage tracing/proprotein convertase subtilisin/kexin type 9 serine protease mutant viral-induced atherosclerotic mouse models. The therapeutic efficacy of a synthetic peptide targeting atherosclerotic plaques was then assessed in Apoe −/− mice. Results: Single-cell RNA sequencing and lineage tracing revealed that epsins 1 and 2 promote EndoMT and that the loss of endothelial epsins inhibits EndoMT marker expression and transforming growth factor-β signaling in vitro and in atherosclerotic mice, which is associated with smaller lesions in the Apoe −/− mouse model. Mechanistically, the loss of endothelial cell epsins results in increased fibroblast growth factor receptor-1 expression, which inhibits transforming growth factor-β signaling and EndoMT. Epsins directly bind ubiquitinated fibroblast growth factor receptor-1 through their ubiquitin-interacting motif, which results in endocytosis and degradation of this receptor complex. Consequently, administration of a synthetic ubiquitin-interacting motif–containing peptide atheroma ubiquitin-interacting motif peptide inhibitor significantly attenuates EndoMT and progression of atherosclerosis. Conclusions: We conclude that epsins potentiate EndoMT during atherogenesis by increasing transforming growth factor-β signaling through fibroblast growth factor receptor-1 internalization and degradation. Inhibition of EndoMT by reducing epsin–fibroblast growth factor receptor-1 interaction with a therapeutic peptide may represent a novel treatment strategy for atherosclerosis.

Current clinical applications of protein therapy are largely limited to systemically accessible targets in vascular or extracellular areas. Major obstacles to the widespread application of protein therapeutics in cancer treatment include low membrane permeability and endosomal entrapment. Herein, we report a multistage nanoparticle (NP) strategy for systemic and cytosolic protein delivery to tumor cells, by encapsulating a protein conjugate, tetra-guanidinium (TG)-modified saporin, into tumor microenvironment (TME) pH-responsive polymeric NPs. Upon reaching the tumor site after systemic circulation, the polymeric NPs respond rapidly to the acidic tumor microenvironment and release the TG-saporin conjugates, which penetrate the tumor tissue and enter into tumor cells via TG-mediated cytosolic transportation. The TG-saproin NPs showed potent inhibition of lung cancer cell growth in vitro and in vivo. We expect that this multistage NP delivery strategy with long blood circulation, deep tumor penetration, and efficient cytosolic transport may be applicable to various therapeutic proteins for effective cancer treatment.

This study aimed to explore the effect of ultrasound-stimulated microbubbles (USMBs) on tumor radiosensitivity in esophageal carcinoma (EC). The human EC cell line KYSE-510 and human umbilical vein endothelial cells (HUVECs) were exposed to radiation alone or in combination with USMBs. CCK-8, colony formation, and EdU assays were used to determine cell viability and proliferation. Cell apoptosis was assessed using flow cytometry. Cell migration and invasion were examined by wound healing and transwell assays. Western blotting showed that the protein levels were associated with apoptosis, epithelial–mesenchymal transition (EMT), and angiogenesis. An endothelial tube-forming assay was used to detect the angiogenic activity of HUVECs. Xenograft experiments were used to examine the effect of USMBs on EC radiosensitivity in vivo. The expression of Ki-67 in tumors was detected using immunohistochemistry. USMBs enhanced the suppressive effect of radiation on proliferation, migration, invasion, and EMT, and promoted radiation-induced apoptosis in EC cells in vitro. Angiogenesis in EC was suppressed by radiation and further inhibited by the combination of radiation and USMBs. In vivo experiments revealed that USMBs increased the radiosensitivity of ECs to tumor growth. Collectively, USMBs enhanced the effects of radiotherapy in esophageal carcinoma.

Nanotechnology could improve our understanding of the pathophysiology of atherosclerosis and contribute to the development of novel diagnostic and therapeutic strategies to further reduce the risk of cardiovascular disease. Macrophages have key roles in atherosclerosis progression and, therefore, macrophage-associated pathological processes are important targets for both diagnostic imaging and novel therapies for atherosclerosis. In this Review, we highlight efforts in the past two decades to develop imaging techniques and to therapeutically manipulate macrophages in atherosclerotic plaques with the use of rationally designed nanoparticles. We review the latest progress in nanoparticle-based imaging modalities that can specifically target macrophages. Using novel molecular imaging technology, these modalities enable the identification of advanced atherosclerotic plaques and the assessment of the therapeutic efficacy of medical interventions. Additionally, we provide novel perspectives on how macrophage-targeting nanoparticles can deliver a broad range of therapeutic payloads to atherosclerotic lesions. These nanoparticles can suppress pro-atherogenic macrophage processes, leading to improved resolution of inflammation and stabilization of plaques. Finally, we propose future opportunities for novel diagnostic and therapeutic strategies and provide solutions to challenges in this area for the purpose of accelerating the clinical translation of nanomedicine for the treatment of atherosclerotic vascular disease., In this Review, Tao and colleagues discuss the latest advances in nanoparticle-based imaging and therapeutic approaches targeting macrophages in atherosclerotic plaques, highlight opportunities for novel macrophage-targeting nanomedicines for atherosclerosis diagnosis and treatment, and provide solutions to challenges in this area to accelerate clinical translation., Key points Because macrophages have key roles in atherosclerosis progression, macrophage-mediated pro-atherosclerotic processes are important targets for both diagnostic imaging and novel therapies for atherosclerosis.Nanotechnology is particularly advantageous in its capacity to substantially improve the pharmacokinetic profile and chemical stability of encapsulated diagnostic and therapeutic agents for atherosclerosis management.The rational design of nanoparticle-based imaging agents that can specifically target inflammatory macrophages in atherosclerotic plaques offers diagnostic potential to non-invasively quantify atherosclerosis plaque burden, evaluate the efficacy of medical interventions and serve as surrogate end points.Targeted nanotherapeutics that can modulate plaque macrophage functions by the activation or suppression of specific signalling pathways have shown great promise in preclinical models by improving therapeutic efficacy and reducing off-target and systemic adverse effects.Rapid advances in nanotechnology and bioengineering and an improved understanding of atherosclerotic pathophysiology have accelerated the development of novel nanotherapeutics for atherosclerosis diagnosis and treatment.The success of various nanomedicine-based approaches in preclinical studies of atherosclerosis and their use in human cancer bode well for their future application in the diagnosis and treatment of patients with cardiovascular disease.

Background: Excess cholesterol accumulation in lesional macrophages elicits complex responses in atherosclerosis. Epsins, a family of endocytic adaptors, fuel the progression of atherosclerosis; however, the underlying mechanism and therapeutic potential of targeting Epsins remains unknown. In this study, we determined the role of Epsins in macrophage-mediated metabolic regulation. We then developed an innovative method to therapeutically target macrophage Epsins with specially designed S2P-conjugated lipid nanoparticles, which encapsulate small-interfering RNAs to suppress Epsins. Methods: We used single-cell RNA sequencing with our newly developed algorithm MEBOCOST (Metabolite-mediated Cell Communication Modeling by Single Cell Transcriptome) to study cell-cell communications mediated by metabolites from sender cells and sensor proteins on receiver cells. Biomedical, cellular, and molecular approaches were utilized to investigate the role of macrophage Epsins in regulating lipid metabolism and transport. We performed this study using myeloid-specific Epsin double knockout (LysM-DKO) mice and mice with a genetic reduction of ABCG1 (ATP-binding cassette subfamily G member 1; LysM-DKO-ABCG1 fl/+ ). The nanoparticles targeting lesional macrophages were developed to encapsulate interfering RNAs to treat atherosclerosis. Results: We revealed that Epsins regulate lipid metabolism and transport in atherosclerotic macrophages. Inhibiting Epsins by nanotherapy halts inflammation and accelerates atheroma resolution. Harnessing lesional macrophage-specific nanoparticle delivery of Epsin small-interfering RNAs, we showed that silencing of macrophage Epsins diminished atherosclerotic plaque size and promoted plaque regression. Mechanistically, we demonstrated that Epsins bound to CD36 to facilitate lipid uptake by enhancing CD36 endocytosis and recycling. Conversely, Epsins promoted ABCG1 degradation via lysosomes and hampered ABCG1-mediated cholesterol efflux and reverse cholesterol transport. In a LysM-DKO-ABCG1 fl/+ mouse model, enhanced cholesterol efflux and reverse transport due to Epsin deficiency was suppressed by the reduction of ABCG1. Conclusions: Our findings suggest that targeting Epsins in lesional macrophages may offer therapeutic benefits for advanced atherosclerosis by reducing CD36-mediated lipid uptake and increasing ABCG1-mediated cholesterol efflux.

BACKGROUNDExcess cholesterol accumulation in lesional macrophages elicits complex responses in atherosclerosis. Epsins, a family of endocytic adaptors, fuel the progression of atherosclerosis; however, the underlying mechanism and therapeutic potential of targeting Epsins remains unknown. In this study, we determined the role of Epsins in macrophage-mediated metabolic regulation. We then developed an innovative method to therapeutically-target macrophage Epsins with specially-designed S2P-conjugated lipid nanoparticles (NPs), which encapsulate small interfering RNAs to suppress Epsins.METHODSWe used single cell RNA sequencing (scRNA-seq) with our newly developed algorithm MEBOCOST to study cell-cell communications mediated by metabolites from sender cells and sensor proteins on receiver cells. Biomedical, cellular and molecular approaches were utilized to investigate the role of macrophage Epsins in regulating lipid metabolism and transport. We performed this study using myeloid-specific Epsin double knockout (LysM-DKO) mice and mice with a genetic reduction of ABCG1 (LysM-DKO-ABCG1fl/+). The NPs targeting lesional macrophages were developed to encapsulate interfering RNAs to treat atherosclerosis.RESULTSWe revealed that Epsins regulate lipid metabolism and transport in atherosclerotic macrophages. Inhibiting Epsins by nanotherapy halts inflammation and accelerates atheroma resolution. Harnessing lesional macrophage-specific NP delivery of Epsin siRNAs, we showed that silencing of macrophage Epsins markedly diminished atherosclerotic plaque size and promoted plaque regression. Mechanistically, we demonstrated that Epsins bound to CD36 to facilitate lipid uptake by enhancing CD36 endocytosis and recycling. Conversely, Epsins promoted ABCG1 degradation via lysosomes and hampered ABCG1-mediated cholesterol efflux and reverse cholesterol transport. In a LysM-DKO-ABCG1fl/+ mouse model, enhanced cholesterol efflux and reverse transport due to Epsin deficiency was suppressed by the reduction of ABCG1.CONCLUSIONSOur findings suggest that targeting Epsins in lesional macrophages may offer therapeutic benefits for advanced atherosclerosis by reducing CD36-mediated lipid uptake and increasing ABCG1-mediated cholesterol efflux.Novelty and SignificanceWHAT IS KNOWN?Epsin endocytic adaptor proteins are upregulated in human and mouse atherosclerotic lesionsLesional macrophages internalize lipids primarily through scavenger receptor-mediated endocytosis such as CD36 and SR-AMacrophage-mediated cholesterol efflux and reverse cholesterol transport is crucial to atheroma resolutionWHAT NEW INFORMATION DOES THIS ARTICLE CONTRIBUTE?ScRNA-seq combined with the newly-developed algorithm MEBOCOST reveals that Epsins are involved in macrophage-mediated lipid metabolic regulationMacrophage epsins promote lipid uptake by targeting CD36 endocytosis and membrane recycling via the Epsin ENTH domainEpsins bind ubiquitinated ABCG1—resulting in the endocytosis and lysosomal degradation of this cholesterol transporter, which reduces cholesterol efflux.Macrophage-specific, nanoparticle-mediated RNAi delivery exhibits a therapeutic benefit for the treatment of atherosclerosisAtherosclerotic plaque regression using this nanoparticle delivery platform represents a clinically-relevant approach for the treatment of advance atherosclerosisBRIEF SUMMARYDespite the development of new cholesterol-lowering therapies, including the recently approved PCSK9 small interfering RNA (siRNA) antagonists, patients still face a tremendous risk of developing major acute cardiovascular events resulting from chronic inflammation in the plaque. We employed a novel nanomedicine platform containing a stabilin-2 targeting peptide (S2P) to deliver Epsin-specific siRNAs to lesional macrophages. We discovered that inhibition of these adaptor proteins in lesional macrophages significantly diminished plaque size and necrotic core area, increased fibrous cap thickness, and promoted plaque regression.

Resolving atheroma and hindering their transition to vulnerable atherosclerotic plaque is pivotal in preventing deadly episodes such as heart attacks and strokes. Despite recent advances in the treatment, atherosclerosis remains the root cause of death worldwide. Excess cholesterol accumulation and deposition trigger a complex inflammatory response in atherosclerosis. Our recent studies demonstrate that epsins, a family of endocytic adaptors, are critically responsible for the aforesaid events in atherosclerosis; however, the underlying mechanisms and whether targeting epsins hinders cholesterol uptake, promote cholesterol efflux and reverse transport in macrophages to reduce inflammation and accelerate atheroma resolution remains an open question. To explore the therapeutic intervention by harnessing recent development in nanomedicine, we silenced epsins in lesional macrophages by specific delivery of nanoparticles (NPs) carrying epsin siRNAs. We showed that inhibit epsins significantly diminished atherosclerotic plaque size and promoted plaque regression. Mechanistically, epsins bind to CD36 to facilitate CD36-mediated lipid uptake by enhancing its endocytosis and recycling. Conversely, epsins promote ABCG1 degradation via lysosomes and hamper ABCG1-mediated cholesterol efflux and reverse cholesterol transport. Furthermore, myeloid-specific epsins double knockout mice (LysM-DKO) harboring a genetically reduced ABCG1 level (LysM-DKO-ABCG1 fl/+ ) were generated. In LysM-DKO-ABCG1 fl/+ macrophages, enhanced cholesterol efflux and reverse transport due to epsins deficiency was suppressed. Our findings suggest that targeting epsins in lesional macrophages may offer therapeutic benefits in preventing or treating advanced atherosclerosis.

Funding: This work was supported by the European Research Council (ERC) Starting Grant (ERC-StG-2019-848325 to J. Conde) and the Fundação para a Ciência e a Tecnologia FCT Grant (PTDC/BTM-MAT/4738/2020 to J. Conde). J.S. acknowledges US National Institute of Health (NIH) grants (R01CA200900, R01HL156362 and R01HL159012), the US DoD PRCRP Idea Award with Special Focus (W81XWH1910482), the Lung Cancer Discovery Award from the American Lung Association and the Innovation Discovery Grants award from the Mass General Brigham. H.L., D.Y. and X.Z. were supported by the National Key R&D Program of China (no. 2020YFA0710700), the National Natural Science Foundation of China (nos 21991132, 52003264, 52021002 and 52033010) and the Fundamental Research Funds for the Central Universities (no. WK2060000027). There is growing need for a safe, efficient, specific and non-pathogenic means for delivery of gene therapy materials. Nanomaterials for nucleic acid delivery offer an unprecedented opportunity to overcome these drawbacks; owing to their tunability with diverse physico-chemical properties, they can readily be functionalized with any type of biomolecules/moieties for selective targeting. Nucleic acid therapeutics such as antisense DNA, mRNA, small interfering RNA (siRNA) or microRNA (miRNA) have been widely explored to modulate DNA or RNA expression Strikingly, gene therapies combined with nanoscale delivery systems have broadened the therapeutic and biomedical applications of these molecules, such as bioanalysis, gene silencing, protein replacement and vaccines. Here, we overview how to design smart nucleic acid delivery methods, which provide functionality and efficacy in the layout of molecular diagnostics and therapeutic systems. It is crucial to outline some of the general design considerations of nucleic acid delivery nanoparticles, their extraordinary properties and the structure–function relationships of these nanomaterials with biological systems and diseased cells and tissues. publishersversion published

Ultrasound (US) is reported to improve the delivery efficiency of drugs loading onto large nanoparticles due to the sonoporation effect. Microbubbles (MBs) can be used as contrast agents of US expanding and contracting under low-amplitude US pressure waves. Ultrasound-stimulated microbubbles (USMBs) therapy is a promising option for the treatment of various cancers as a radiosensitizer. However, its role in esophageal squamous cell carcinoma (ESCC) remains unknown. In our study, human ESCC cell lines (KYSE-410, KYSE-1140) were treated with radiation solely, US alone, or radiation in combination with US or USMBs. The migration and invasion abilities of ESCC cells were examined by wound healing and Transwell assays. ESCC cell apoptosis was assessed using flow cytometry analysis and TUNEL assays. The levels of proteins associated with cell apoptosis and angiogenesis were measured by western blot analysis. A tube formation assay was performed to detect the ESCC cell angiogenesis. We found that USMBs at high levels most effectively most efficiently enhanced the effect of radiation, and significant changes in the viability (48%-51%), proliferation (1%), migration (63%-71%), invasion (52%) and cell apoptosis (31%-50%) of ESCC cells were observed compared with the control group in vitro. The ESCC angiogenesis was inhibited by US or radiation treatment and further inhibited by a combination of radiation and US or USMBs. USMBs at high levels most effectively enhanced the inhibitory effect of radiotherapy on ESCC cell apoptosis. Overall, USMBs enhanced the radiosensitivity of esophageal squamous cell carcinoma cells.Graphical abstractUSMBs treatment enhanced the anti-tumor effect of radiation on ESCC cell proliferation, migration, invasion, angiogenesis and apoptosis in vitro.1USMBs enhance the radiation-induced inhibition on ESCC cell growth2USMBs promote the radiation effect on ESCC cell apoptosis3USMBs enhance radiation-caused suppression on ESCC cell migration and invasion4USMBs enhance the suppression of radiation on ESCC angiogenesis[Figure: see text].

Compared to traditional drug delivery systems, DNA nanostructure-based drug delivery systems have several advantages including programmable sequences, precise size and shape, high drug payloads, excellent biocompatibility and biodegradability. To date, a wide range of chemotherapeutic drug-DNA hybrid nanostructures have been developed for anti-tumor therapy. In this review, the constructions of various DNA nanostructures for anticancer drug delivery are firstly summarized. Next, the anticancer drug loading methods for DNA nanostructures are presented. Then, the recent applications of chemotherapeutic drug-DNA hybrid nanostructures for drug delivery are highlighted. In the end, the challenges and opportunities of the chemotherapeutic drug-DNA hybrid nanostructure-based delivery system are discussed. The designs of drug-DNA hybrid systems, including the constructions of nanostructures and the strategies for drug loading, largely influence the efficiency of drug delivery. Recent studies have focused on the development of novel drug-DNA hybrid systems to acquire more precise and efficient therapy for various diseases. A systematic review of the design strategies of chemotherapeutic drug-DNA hybrid nanostructures will benefit the innovation and development of the chemotherapeutic drug-based chemotherapy in clinics.

With the increasing recognition of the diverse roles and significance of oxidative species in the pathogenesis of many diseases, a tremendous amount of work on the development of oxidative-species-responsive materials has been conducted for 1) detecting oxygen metabolites or diagnosis of oxidative-stress-relevant diseases, 2) reducing oxidative stress in the disease sites, and/or 3) delivering therapeutic and diagnostic agents. In this review, we first discuss the distinct features and biological functions of each oxidative species. Then the selectivity and sensitivity of chemical linkers/groups to specific oxidative species and the underlying chemistry of their particular interactions are systematically elucidated. Their potential biomedical applications are also highlighted. We expect that this comprehensive review will provide more insights for the design and development of oxidative-species-selective materials for more effective diagnostic and therapeutic applications.

Innate immune cells recognize and respond to pathogen-associated molecular patterns. In particular, polysaccharides found in the microbial cell wall are potent activators of dendritic cells (DCs). Here, we report a new class of nanocapsules, termed sugar-capsules, entirely composed of polysaccharides derived from the microbial cell wall. We show that sugar-capsules with a flexible polysaccharide shell and a hollow core efficiently drain to lymph nodes and activate DCs. In particular, sugar-capsules composed of mannan (Mann-capsule) carrying mRNA (mRNA) promote strong DC activation, mRNA translation, and antigen presentation on DCs. Mann-capsules elicit robust antigen-specific CD4+ and CD8α+ T-cell responses with antitumor efficacy in vivo. The strategy presented in this study is generally applicable for utilizing pathogen-derived molecular patterns for vaccines and immunotherapies.

Summary Apoptotic cell clearance by macrophages (efferocytosis) promotes resolution signaling pathways, which can be triggered by molecules derived from the phagolysosomal degradation of apoptotic cells. We show here that nucleotides derived from the hydrolysis of apoptotic cell DNA by phagolysosomal DNase2a activate a DNA−PKcs−mTORC2/Rictor pathway that increases Myc to promote non-inflammatory macrophage proliferation. Efferocytosis-induced proliferation expands the pool of resolving macrophages in vitro and in mice, including zymosan-induced peritonitis, dexamethasone-induced thymocyte apoptosis, and atherosclerosis regression. In the dexamethasone-thymus model, hematopoietic Rictor deletion blocked efferocytosing macrophage proliferation, apoptotic cell clearance, and tissue resolution. In atherosclerosis regression, silencing macrophage Rictor or DNase2a blocked efferocyte proliferation, apoptotic cell clearance, and plaque stabilization. In view of previous work showing that other types of apoptotic cell cargo can promote resolution in individual efferocytosing macrophages, the findings here suggest that signaling-triggered apoptotic cell-derived nucleotides can amplify this benefit by increasing the number of these macrophages.

RNA interference (RNAi) is a powerful approach in the treatment of various diseases including cancers. The clinical translation of small interfering RNA (siRNA)-based therapy requires safe and efficient delivery vehicles. Here, we report a siRNA nanogels (NG)-based delivery vehicle, which is driven directly by the intercalation between nucleic acid bis-intercalator and siRNA molecules. The intercalation-based siRNA NG exhibits good physiological stability and can enter cells efficiently via different endocytosis pathways. Furthermore, the siRNA NG can not only silence the target genes in vitro but also significantly inhibit the tumor growth in vivo. Therefore, this study provides an intercalation-based strategy for the development of a siRNA delivery platform for cancer therapy. To the best of our knowledge, this is the first report of the intercalation-driven siRNA NG.

BACKGROUND: To diagnose gastroparesis, it is necessary to assess gastric emptying accurately. This study aims to investigate the role of three-dimensional ultrasonography (3-D US) on the measurement of gastric volume to evaluate gastric accommodation in healthy patients. METHODS: In this study, 21 volunteers, 46 patients with diabetic gastroparesis (DG), and 22 patients with postsurgical gastroparesis (PSG) underwent 3-D US after oral administration of 250 mL gastrointestinal contrast at 2, 30, 60, and 90 min. The volume of the contrast agent in the stomach was then calculated using the virtual organ computer-aided analysis (VOCAL) (Virtual Organ Computer-aided AnaLysis, General Electric Medical Systems, Kretztechnik, Zipf, Austria). RESULTS: In the DG group, the gastric residue volumes at postprandial 60 and 90 min were significantly higher than those in the healthy group (P

The effectivity of cancer immunotherapies is hindered by immunosuppressive tumour microenvironments that are poorly infiltrated by effector T cells and natural killer cells. In infection and autoimmune disease, the recruitment and activation of effector immune cells is coordinated by pro-inflammatory T helper 17 (T

Immunotherapy with immune checkpoint blockade (ICB) has shown limited benefits in hepatocellular carcinoma (HCC) and other cancers, mediated in part by the immunosuppressive tumor microenvironment (TME). As p53 loss of function may play a role in immunosuppression, we herein examine the effects of restoring p53 expression on the immune TME and ICB efficacy. We develop and optimize a CXCR4-targeted mRNA nanoparticle platform to effectively induce p53 expression in HCC models. Using p53-null orthotopic and ectopic models of murine HCC, we find that combining CXCR4-targeted p53 mRNA nanoparticles with anti-PD-1 therapy effectively induces global reprogramming of cellular and molecular components of the immune TME. This effect results in improved anti-tumor effects compared to anti-PD-1 therapy or therapeutic p53 expression alone. Thus, our findings demonstrate the reversal of immunosuppression in HCC by a p53 mRNA nanomedicine when combined with ICB and support the implementation of this strategy for cancer treatment.

Biocompatible nano-antioxidants composed of natural molecules/materials, such as dopamine and melanin, are of great interest for diverse biomedical applications. However, the lack of understanding of the precise structure of these biomaterials and thus the actual dose of effective components impedes their advancement to translation. Herein, a strategy to mimic in situ melanin formation and explore its antioxidative applications is reported, by developing a PEGylated, phenylboronic-acid-protected L-DOPA precursor (PAD) that can self-assemble into well-defined nanoparticles (PADN). Exposure to oxidative species leads to deprotection of phenylboronic acids, transforming PADN to PEG-L-DOPA, which, similar to the biosynthetic pathway of melanin, can be oxidized and polymerized into an antioxidative melanin-like structure. With ultrahigh stability and superior antioxidative activity, the PADN shows remarkable efficacy in prevention and treatment of acute liver injury/failure. Moreover, the in situ structure transformation enables PADN to visualize damaged tissue noninvasively by photoacoustic imaging. Overall, a bioinspired antioxidant with precise structure and site-specific biological activity for theranostics of oxidative stress-related diseases is described.

Oxidative stress, as results of deregulated production and accumulation of reactive oxygen and nitrogen species, is a common hallmark in a multitude of human diseases. Enormous studies have demonstrated that such imbalance of redox homeostasis is implicated in both disease initiation and progress. The development of antioxidants to target overexpressed reactive oxygen and/or nitrogen species, which is referred to as antioxidant therapy, has thus represented an important therapeutic option for the oxidative stress relevant diseases. Over the past decade, antioxidative nanotechnologies have been emerging as an alternative strategy and have shown many unique advantages over conventional antioxidants (such as enzymes and small molecules), owing to their advantageous pharmacokinetics and biodistribution, stable antioxidative activity, and more importantly, intrinsic multiple radicals scavenging properties. This review provides a comprehensive and up-to-date overview on antioxidative nanomaterials in terms of the category, their antioxidative activities and underlying mechanisms, and the potential biomedical applications. In addition, the challenges in this exciting field and future perspectives are also discussed.

With recent advances in polymer chemistry, materials science, and nanotechnology, pH-responsive polymers have a significant impact in a number of diverse fields. Fundamental studies of these polymers are thus highly desirable as they may lead to new insights into the rational design of pH-responsive polymers with specific effects. In this Perspective, we focus on the nanobuffering of pH-responsive polymers (NBPRP). Although researchers have known of such buffering effects for more than a century, for example, in the context of the Henderson-Hasselbalch equation, modern synthesis and analysis routes now enable us to analyze these effects on the nanometer scale. In this way, the NBPRP phenomenon was explicitly defined and described by Gauthier and colleagues in the February issue of ACS Nano. Here, we highlight several potential areas in which the NBPRP could enable innovative classes of biological applications. We expect deeper mechanistic understanding of nanobuffering effects induced by pH-responsive polymers to have a significant impact on the future development and applications of these polymers.

Cisplatin-based chemotherapy is a widely used first-line strategy for numerous cancers. However, drug resistances are often inevitable accompanied by the long-term use of cisplatin in vivo, significantly hampering its therapeutic efficacy and clinical outcomes. Among others, autophagy induction is one of the most common causes of tumor resistance to cisplatin. Herein, a self-assembled nanoprodrug platform was developed with the synergistic effect of cisplatin and RNAi to fight against cisplatin-resistant lung cancer. The nanoprodrug platform consists of three molecular modules, including prodrug complex of Pt(IV)-peptide-bis(pyrene), DSPE-PEG, and cRGD-modified DSPE-PEG. The Pt(IV) is immobilized with peptide via amide bonds, allowing the Pt(IV) to be loaded with a loading efficiency of >95% and rapid-release active platinum ions (Pt(II)) in the presence of glutathione (GSH). Meanwhile, the peptide of the prodrug complex could efficiently deliver Beclin1 siRNA ( Beclin1 is an autophagy initiation factor) to the cytoplasm, thereby leading to autophagy inhibition. In addition, incorporation of DSPE-PEG and cRGD-modified DSPE-PEG molecules improves the biocompatibility and cellular uptake of the nanoprodrug platform. In vivo results also indicate that the nanoprodrug platform significantly inhibits the growth of a cisplatin-resistant tumor on xenograft mice models with a remarkable inhibition rate, up to 84% after intravenous injection.

The direct connection between a photosensitizer and an electron mediator, achieved by a precise arrangement based on chlorosome, provides photosynthetic bacteria the maximum efficiency in solar energy conversion. Herein, this study reports the fabrication of a biomimicking chlorosome for biocatalyzed artificial photosynthesis through self-assembly of simple molecules to functional systems. TCPP/EYx/Rh8–x macromolecules, synthesized through a sequential amidation reaction of porphyrin (TCPP), eosin Y (EY), and [Cp*RhCl2]2, were found to self-assemble into chlorosome-mimicking supramolecular assemblies through noncovalent interactions. Intra- and intermolecular dual channels for enhancing electron transfer were constructed in TCPP/EYx/Rh8–x supramolecular assemblies. In addition, the energy band structure of TCPP/EY4/Rh4 supramolecular assemblies also made a perfect coordination with oxidation and reduction potentials of an electron donor and NAD+, which led to a fast and oriented electron transfer along th...

We have synthesized a PEGylated, phenylboronic acid modified L-DOPA pro-antioxidant (pPAD) that can self-assemble into nanoparticles (pPADN) for the loading of a model glucocorticoid dexamethasone (Dex) through 1,3-diol/phenylboronic acid chemistry and hydrophobic interactions for more effective treatment of inflammation. Upon exposure to ROS, pPADN convert into the active form of L-DOPA, and a cascade of oxidative reactions transform it into antioxidative melanin-like materials. Concomitantly, the structural transformation of pPADN triggers the specific release of Dex, along with the acidic pH of inflammatory tissue. In a rat model of osteoarthritis, Dex-loaded pPADN markedly mitigate synovial inflammation, suppress joint destruction and cartilage matrix degradation, with negligible in vivo toxicity. Moreover, in situ structural transformation makes pPADN suitable for noninvasive monitoring of therapeutic effects as a photoacoustic imaging contrast agent.

Objective: ODC (ornithine decarboxylase)-dependent putrescine synthesis promotes the successive clearance of apoptotic cells (ACs) by macrophages, contributing to inflammation resolution. However, it remains unknown whether ODC is required for other arms of the resolution program. Approach and Results: RNA sequencing of ODC-deficient macrophages exposed to ACs showed increases in mRNAs associated with heightened inflammation and decreases in mRNAs related to resolution and repair compared with WT (wild type) macrophages. In zymosan peritonitis, myeloid ODC deletion led to delayed clearance of neutrophils and a decrease in the proresolving cytokine, IL (interleukin)-10. Nanoparticle-mediated silencing of macrophage ODC in a model of atherosclerosis regression lowered IL-10 expression, decreased efferocytosis, enhanced necrotic core area, and reduced fibrous cap thickness. Mechanistically, ODC deletion lowered basal expression of MerTK (MER tyrosine-protein kinase)—an AC receptor—via a histone methylation–dependent transcriptional mechanism. Owing to lower basal MerTK, subsequent exposure to ACs resulted in lower MerTK-Erk (extracellular signal-regulated kinase) 1/2–dependent IL-10 production. Putrescine treatment of ODC-deficient macrophages restored the expression of both MerTK and AC-induced IL-10. Conclusions: These findings demonstrate that ODC-dependent putrescine synthesis in macrophages maintains a basal level of MerTK expression needed to optimally resolve inflammation upon subsequent AC exposure. Graphic Abstract: A graphic abstract is available for this article.

Aims Recent evidence suggests that ‘vulnerable plaques’, which have received intense attention as underlying mechanism of acute coronary syndromes over the decades, actually rarely rupture and cause clinical events. Superficial plaque erosion has emerged as a growing cause of residual thrombotic complications of atherosclerosis in an era of increased preventive measures including lipid lowering, antihypertensive therapy, and smoking cessation. The mechanisms of plaque erosion remain poorly understood, and we currently lack validated effective diagnostics or therapeutics for superficial erosion. Eroded plaques have a rich extracellular matrix, an intact fibrous cap, sparse lipid, and few mononuclear cells, but do harbour neutrophil extracellular traps (NETs). We recently reported that NETs amplify and propagate the endothelial damage at the site of arterial lesions that recapitulate superficial erosion in mice. We showed that genetic loss of protein arginine deiminase (PAD)-4 function inhibited NETosis and preserved endothelial integrity. The current study used systemic administration of targeted nanoparticles to deliver an agent that limits NETs formation to probe mechanisms of and demonstrate a novel therapeutic approach to plaque erosion that limits endothelial damage. Methods and results We developed Collagen IV-targeted nanoparticles (Col IV NP) to deliver PAD4 inhibitors selectively to regions of endothelial cell sloughing and collagen IV-rich basement membrane exposure. We assessed the binding capability of the targeting ligand in vitro and evaluated Col IV NP targeting to areas of denuded endothelium in vivo in a mouse preparation that recapitulates features of superficial erosion. Delivery of the PAD4 inhibitor GSK484 reduced NET accumulation at sites of intimal injury and preserved endothelial continuity. Conclusions NPs directed to Col IV show selective uptake and delivery of their payload to experimentally eroded regions, illustrating their translational potential. Our results further support the role of PAD4 and NETs in superficial erosion.

Introduction: Superficial plaque erosion has emerged as a growing cause of residual thrombotic complications of atherosclerosis in an era of effective lipid lowering, anti-hypertensive therapy, and smoking cessation. The mechanisms of plaque erosion remain poorly understood, and we currently lack validated effective diagnostics or therapeutics for superficial erosion. Lesions complicated by erosion have a rich extracellular matrix, sparse lipid, and few mononuclear cells, but do harbor neutrophil extracellular traps (NETs). We recently reported that NETs amplify and propagate the endothelial damage at the site of arterial lesions that recapitulate in mice elements of superficial erosion. We previously showed that genetic loss of protein arginine deiminase (PAD)-4 function inhibited NETosis and preserved endothelial integrity. Hypothesis: We hypothesized that Col IV-targeted NPs (Col IV-NPs) can deliver PAD4 inhibitors selectively to regions of EC sloughing and collagen IV-rich basement membrane exposure, and attenuate the amplification, persistence, and propagation of superficial erosion and consequent thrombosis. Methods: We developed Col IV-NPs to deliver PAD4 inhibitors selectively to regions of endothelial cell sloughing and collagen IV-rich basement membrane exposure using our validated experimental preparation that reproduces in mice some of the conditions ascribed to lesions associated with superficial erosion. Results and Conclusions: We first demonstrated the binding of the targeting ligand in vitro and evaluated Col IV NP targeting towards areas of denuded endothelium in vivo in this mouse preparation. Delivery of the PAD4 inhibitor GSK484 as cargo in these nanoparticles reduced NETs release at sites of eroded areas. Compared to non-targeted NPs, Col IV NPs showed a 1.8-fold increased accumulation at regions of endothelial injury (p

Six cationic lipidoid fluorodendrimers are synthesized to construct hybrid lipid–polymer nanoparticles for siRNA delivery. By screening the nanoplatforms including fluorodendrimers with different chemical structures, the optimized nanoparticle NPF13-5 mediates the most efficient silencing of prohibitin 1, inhibition of cell proliferation, and induction of cell apoptosis towards A549 lung adenocarcinoma cells.

Increasing clinical evidence has demonstrated that the deletion or mutation of tumor suppressor genes such as the gene-encoding phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in cancer cells may correlate with an immunosuppressive tumor microenvironment (TME) and poor response or resistance to immune checkpoint blockade (ICB) therapy. It is largely unknown whether the restoration of functional PTEN may modulate the TME and improve the tumor’s sensitivity to ICB therapy. Here, we demonstrate that mRNA delivery by polymeric nanoparticles can effectively induce expression of PTEN in Pten-mutated melanoma cells and Pten-null prostate cancer cells, which in turn induces autophagy and triggers cell death–associated immune activation via release of damage-associated molecular patterns. In vivo results illustrated that PTEN mRNA nanoparticles can reverse the immunosuppressive TME by promoting CD8(+) T cell infiltration of the tumor tissue, enhancing the expression of proinflammatory cytokines, such as interleukin-12, tumor necrosis factor–α, and interferon-γ, and reducing regulatory T cells and myeloid-derived suppressor cells. The combination of PTEN mRNA nanoparticles with an immune checkpoint inhibitor, anti–programmed death–1 antibody, results in a highly potent antitumor effect in a subcutaneous model of Pten-mutated melanoma and an orthotopic model of Pten-null prostate cancer. Moreover, the combinatorial treatment elicits immunological memory in the Pten-null prostate cancer model.

Two-dimensional (2D) nanosheets are characterized by their ultra-thin structure which sets them apart from their bulk materials. Due to this unique 2D structure, they have a high surface-to-volume ratio that can be beneficial for the delivery of various drugs including therapeutic DNAs and RNAs. In addition, various 2D materials exhibit excellent photothermal conversion efficiency when exposed to the near infrared (NIR) light. Therefore, this 2D nanosheet-based photonic nanomedicine has been gaining tremendous attention as both gene delivering vehicles and photothermal agents, which create synergistic effects in the treatment of different diseases. In this review, we briefly provide an overview of the following two parts regarding this type of photonic nanomedicine: (1) mechanism and advantages of nanosheets in gene delivery and photothermal therapy, respectively. (2) mechanism of synergistic effects in nanosheet-mediated combined gene and photothermal therapies and their examples in a few representative nanosheets (e.g., graphene oxide, black phosphorus, and translational metal dichalcogenide). We also expect to provide some deep insights into the possible opportunities associated with the emerging 2D nanosheets for synergistic nanomedicine research.

Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a well-characterized tumour-suppressor gene that is lost or mutated in about half of metastatic castration-resistant prostate cancers and in many other human cancers. The restoration of functional PTEN as a treatment for prostate cancer has, however, proven difficult. Here, we show that PTEN messenger RNA (mRNA) can be reintroduced into PTEN-null prostate cancer cells in vitro and in vivo via its encapsulation in polymer-lipid hybrid nanoparticles coated with a polyethylene glycol shell. The nanoparticles are stable in serum, elicit low toxicity and enable high PTEN mRNA transfection in prostate cancer cells. Moreover, significant inhibition of tumour growth is achieved when delivered systemically in multiple mouse models of prostate cancer. We also show that the restoration of PTEN function in PTEN-null prostate cancer cells inhibits the phosphatidylinositol 3-kinase (PI3K)-AKT pathway and enhances apoptosis. Our findings provide proof-of-principle evidence of the restoration of mRNA-based tumour suppression in vivo.

Loss of function in tumor suppressor genes is commonly associated with the onset/progression of cancer and treatment resistance. The p53 tumor suppressor gene, a master regulator of diverse cellular pathways, is frequently altered in various cancers, for example, in ~36% of hepatocellular carcinomas (HCCs) and ~68% of non-small cell lung cancers (NSCLCs). Current methods for restoration of p53 expression, including small molecules and DNA therapies, have yielded progressive success, but each has formidable drawbacks. Here, a redox-responsive nanoparticle (NP) platform is engineered for effective delivery of p53-encoding synthetic messenger RNA (mRNA). We demonstrate that the synthetic p53-mRNA NPs markedly delay the growth of p53-null HCC and NSCLC cells by inducing cell cycle arrest and apoptosis. We also reveal that p53 restoration markedly improves the sensitivity of these tumor cells to everolimus, a mammalian target of rapamycin (mTOR) inhibitor that failed to show clinical benefits in advanced HCC and NSCLC. Moreover, cotargeting of tumor-suppressing p53 and tumorigenic mTOR signaling pathways results in marked antitumor effects in vitro and in multiple animal models of HCC and NSCLC. Our findings indicate that restoration of tumor suppressors by the synthetic mRNA NP delivery strategy could be combined together with other therapies for potent combinatorial cancer treatment.

Despite the broad antitumor spectrum of cisplatin, its therapeutic efficacy in cancer treatment is compromised by the development of drug resistance in tumor cells and systemic side effects. A close correlation has been drawn between cisplatin resistance in tumor cells and increased levels of intracellular thiol-containing species, especially glutathione (GSH). The construction of a unique nanoparticle (NP) platform composed of poly(disulfide amide) polymers with a high disulfide density for the effective delivery of Pt(IV) prodrugs capable of reversing cisplatin resistance through the disulfide-group-based GSH-scavenging process, as described herein, is a promising route by which to overcome limitations associated with tumor resistance. Following systematic screening, the optimized NPs (referred to as CP5 NPs) showed a small particle size (76.2 nm), high loading of Pt(IV) prodrugs (15.50% Pt), a sharp response to GSH, the rapid release of platinum (Pt) ions, and notable apoptosis of cisplatin-resistant A2780cis cells. CP5 NPs also exhibited long blood circulation and high tumor accumulation after intravenous injection. Moreover, in vivo efficacy and safety results showed that CP5 NPs effectively inhibited the growth of cisplatin-resistant xenograft tumors with an inhibition rate of 83.32% while alleviating serious side effects associated with cisplatin. The GSH-scavenging nanoplatform is therefore a promising route by which to enhance the therapeutic index of Pt drugs used currently in cancer treatment.

Extra domain B of fibronectin (FN-EDB) is upregulated in the extracellular matrix during tissue remodeling and has been postulated as a potential biomarker for atherosclerosis, yet no systematic test for FN-EDB in plaques has been reported. We hypothesized that FN-EDB expression would intensify in advanced plaques. Furthermore, engineering of FN-EDB-targeted nanoparticles (NPs) could enable imaging/diagnosis and local delivery of payloads to plaques. Methods: The amount of FN-EDB in human atherosclerotic and normal arteries (ages: 40 to 85 years) was assessed by histological staining and quantification using an FN-EDB-specific aptide (APTFN-EDB). FN-EDB-specific NPs that could serve as MRI beacons were constructed by immobilizing APTFN-EDB on the NP surface containing DTPA[Gd]. MRI visualized APTFN-EDB-[Gd]NPs administered to atherosclerotic apolipoprotein E-deficient mice in the brachiocephalic arteries. Analysis of the ascending-to-descending thoracic aortas and the aortic roots of the mice permitted quantitation of Gd, FN-EDB, and APTFN-EDB-[Gd]NPs. Cyanine, a model small molecule drug, was used to study the biodistribution and pharmacokinetics of APTFN-EDB-NPs to evaluate their utility for drug delivery. Results: Atherosclerotic tissues had significantly greater FN-EDB-positive areas than normal arteries (P < 0.001). This signal pertained particularly to Type III (P < 0.01), IV (P < 0.01), and V lesions (P < 0.001) rather than Type I and II lesions (AHA classification). FN-EDB expression was positively correlated with macrophage accumulation and neoangiogenesis. Quantitative analysis of T1-weighted images of atherosclerotic mice revealed substantial APTFN-EDB-[Gd]NPs accumulation in plaques compared to control NPs, conventional MRI contrast agent (Gd-DTPA) or accumulation in wild-type C57BL/6J mice. Additionally, the APTFN-EDB-NPs significantly prolonged the blood-circulation time (t1/2: ~ 6 h) of a model drug and increased its accumulation in plaques (6.9-fold higher accumulation vs. free drug). Conclusions: Our findings demonstrate augmented FN-EDB expression in Type III, IV, and V atheromata and that APTFN-EDB-NPs could serve as a platform for identifying and/or delivering agents locally to a subset of atherosclerotic plaques.

Nanotechnology-mediated antioxidative therapy is emerging as a novel strategy for treating a myriad of important diseases through scavenging excessive reactive oxygen and nitrogen species (RONS), a mechanism critical in disease development and progression. However, similar to antioxidative enzymes, currently studied nano-antioxidants have demonstrated scavenging activity to specific RONS, and sufficient antioxidative effects against multiple RONS generated in diseases remain elusive. Here we propose to develop bioinspired melanin nanoparticles (MeNPs) for more potent and safer antioxidative therapy. While melanin is known to function as a potential radical scavenger, its antioxidative mechanisms are far from clear and its applications for the treatment of RONS-associated diseases have yet to be well explored. In this study, we provide for the first time exhaustive characterization of the activities of MeNPs against multiple RONS including O2•−, H2O2, •OH, •NO, and ONOO−, the main toxic RONS generated in diseases. The potential of MeNPs for antioxidative therapy has also been evaluated in vitro and in a rat model of ischemic stroke. In addition to the broad defense against these RONS, MeNPs can also attenuate the RONS-triggered inflammatory responses through suppressing the expression of inflammatory mediators and cytokines. In vivo results further demonstrate that these unique multi-antioxidative, anti-inflammatory and biocompatible features of MeNPs contribute to their effective protection of ischemic brains with negligible side effects.

The present work proposes a unique de-PEGylation strategy for controllable delivery of small interfering RNA (siRNA) using a robust lipid-polymer hybrid nanoparticle (NP) platform. The self-assembled hybrid NPs are composed of a lipid-poly(ethylene glycol) (lipid-PEG) shell and a polymer/cationic lipid solid core, wherein the lipid-PEG molecules can gradually dissociate from NP surface in the presence of serum albumin. The de-PEGylation kinetics of a series of different lipid-PEGs is measured with their respective NPs, and the NP performance is comprehensively investigated in vitro and in vivo. This systematic study reveals that the lipophilic tails of lipid-PEG dictate its dissociation rate from NP surface, determining the uptake by tumor cells and macrophages, pharmacokinetics, biodistribution, and gene silencing efficacy of these hybrid siRNA NPs. Based on our observations, we here propose that lipid-PEGs with long and saturated lipophilic tails might be required for effective siRNA delivery to tumor cells and gene silencing of the lipid-polymer hybrid NPs after systemic administration.

The intrinsic limits of conventional cancer therapies prompted the development and application of various nanotechnologies for more effective and safer cancer treatment, herein referred to as cancer nanomedicine. Considerable technological success has been achieved in this field, but the main obstacles to nanomedicine becoming a new paradigm in cancer therapy stem from the complexities and heterogeneity of tumour biology, an incomplete understanding of nano–bio interactions and the challenges regarding chemistry, manufacturing and controls required for clinical translation and commercialization. This Review highlights the progress, challenges and opportunities in cancer nanomedicine and discusses novel engineering approaches that capitalize on our growing understanding of tumour biology and nano–bio interactions to develop more effective nanotherapeutics for cancer patients.