Nanoparticles retard immune cells recruitment in vivo by inhibiting chemokine expression

Enhanced in vivo Stability and Antitumor Efficacy of PEGylated Liposomes of Paclitaxel Palmitate Prodrug

Purpose

The clinical use of paclitaxel (PTX) in cancer treatment is limited by its poor water solubility, significant toxicity, and adverse effects. This study aimed to propose a straightforward and efficient approach to enhance PTX loading and stability, thereby offering insights for targeted therapy against tumors.

Patients and Methods

We synthesized a paclitaxel palmitate (PTX-PA) prodrug by conjugating palmitic acid (PA) to PTX and encapsulating it into liposomal vehicles using a nano delivery system. Subsequently, we investigated the in vitro and in vivo performance as well as the underlying mechanisms of PTX-PA liposomes (PTX-PA-L).

Results

PTX had a remarkable antitumor effect in vivo and significantly decreased the myelosuppressive toxicity of PTX. Moreover, the introduction of PA increased the lipid solubility of PTX, forming a phospholipid bilayer as a membrane stabilizer, prolonging the circulation time of the drug and indirectly increasing the accumulation of liposomes at the tumor site. Our in vivo imaging experiments demonstrated that PTX-PA-L labeled with DiR has greater stability in vivo than blank liposomes and that PTX-PA-L can target drugs to the tumor site and efficiently release PTX to exert antitumor effects. In a mouse model, the concentration of PTX at the tumor site in the PTX-PA-L group was approximately twofold greater than that of Taxol. However, in a nude mouse model, the concentration of PTX at the tumor site in the PTX-PA-L group was only approximately 0.8-fold greater than that of Taxol. Furthermore, the originally observed favorable pharmacodynamics in normal mice were reversed following immunosuppression. This may be caused by differences in esterase distribution and immunity.

Conclusion

This prodrug technology combined with liposomes is a simple and effective therapeutic strategy with promising developmental prospects in tumor-targeted therapy owing to its ability to convert PTX into a long-circulating nano drug with low toxicity, high pharmacodynamics, and good stability in vivo.

Collaboration in Contradiction: Self-Adaptive Synergistic ROS Generation and Scavenge Balancing Strategies Used for the Infected Wounds Treatment

The rational utilization of ROS is key to treating infected wounds. Exogenous ROS can destroy bacterial structures, quickly kill bacteria, and inhibit secondary infections. However, excess ROS at the wound will cause a secondary inflammatory response. Acute infections exacerbate this damage by increasing endogenous ROS, complicating the maintenance of ROS homeostasis. Therefore, regulating the balance of ROS production and scavenging in wounds has emerged as a promising strategy for wound treatment. Conventional ROS balancing platforms are mostly based on the " all for one" strategy of functional superposition and lack self-adaptability and integration. To subvert this conventional strategy, this study proposes a "one for all" self-adaptive integrated photodynamic therapy (PDT)-antioxidant model to actively regulate the ROS balance. A gelatin-hyaluronic acid hydrogel embedded with Se-modified cerium dioxide nanoparticles (Gel-HA-Se@CeO2 NPs) is designed for treating infected wounds. The Se@CeO2 NPs serve both as nanoenzymes and photosensitizers(PS). As nanoenzymes, they exhibit catalase and superoxide dismutase activities, converting hydrogen peroxide and superoxide anions into oxygen. As a PS, it synergizes with oxygen under NIR irradiation to rapidly produce singlet oxygen. Additionally, Se modification enhances the PDT effects by disrupting bacterial antioxidant systems. In vitro and in vivo experiments revealed that the ROS balance platform polarizes M1-type macrophages to M2-type macrophages, altering the wound microenvironment from proinflammatory to prohealing. RNA sequencing revealed that this hydrogel accelerated the reconstruction of the vascular network of the wound by activating the PI3K/AKT pathway and increasing VEGF secretion.This strategy is believed to be beneficial not only for infected wounds but also for treating other conditions that involve the regulation of reactive oxygen species, such as tumors and bacterial infections.

Unravelling the antioxidant behaviour of self-assembly β-Sheet in silk fibroin

Local oxidative stress in diseases or injury severely hinders cell homeostasis and organ regeneration. Antioxidant therapy is an effective strategy for oxidative stress treatment. Biomaterials with good biocompatibility and reactive oxygen species (ROS) scavenging ability are good choices for antioxidant therapeutics. However, there are few natural biomaterials that are identified with both biocompatibility and strong antioxidant activity. Here, we show, for the first time, that silk fibroin (SF) is a strong antioxidant, which can eliminate ROS in both cells and zebrafish. We further demonstrate that the β-sheet structures turn into a random coiled structure when SF is treated with hydrogen peroxide. The content of β-sheet structures can be increased by heating, thus enhancing the antioxidation properties of SF. Therefore, SF can serve as a good antioxidant biomaterial for therapeutics, and its β-sheet structure-based antioxidation mechanism provides a novel theoretical basis, which could be a new cue for more antioxidant biomaterial discovery and identification.

Enhancing Flexible Neural Probe Performance via Platinum Deposition: Impedance Stability under Various Conditions and In Vivo Neural Signal Monitoring

Monitoring neural activity in the central nervous system often utilizes silicon-based microelectromechanical system (MEMS) probes. Despite their effectiveness in monitoring, these probes have a fragility issue, limiting their application across various fields. This study introduces flexible printed circuit board (FPCB) neural probes characterized by robust mechanical and electrical properties. The probes demonstrate low impedance after platinum coating, making them suitable for multiunit recordings in awake animals. This capability allows for the simultaneous monitoring of a large population of neurons in the brain, including cluster data. Additionally, these probes exhibit no fractures, mechanical failures, or electrical issues during repeated-bending tests, both during handling and monitoring. Despite the possibility of using this neural probe for signal measurement in awake animals, simply applying a platinum coating may encounter difficulties in chronic tests and other applications. Furthermore, this suggests that FPCB probes can be advanced by any method and serve as an appropriate type of tailorable neural probes for monitoring neural systems in awake animals.

Construction and Mechanism of IL-15-Based Coactivated Polymeric Micelles for NK Cell Immunotherapy

Natural killer (NK) cells are an important contributor to cancer immunotherapy, but their antitumor efficacy remains suboptimal. While cytokine-based priming shows promise in enhancing NK-cell activity, its clinical translation faces many challenges, including coactivation of multiple cytokines, poor pharmacokinetics, and limited mechanistic understanding. Here, this work develops a polymeric micelle-based IL-15/IL-2 codelivery system (IL-15/2-PEG-PTMC) for NK-cell activation. In vivo studies demonstrate that half-life of IL-15 and IL-2 and the recruitment of NK cell within tumor tissue are significantly increased after PEG-PTMC loading. Coupled with the coactivation effect of IL-15 and IL-2 conferred by this system, it noticeably delays the growth of tumors compared to conventional NK-cell activation approach, that is free IL-15 and IL-2. It is also surprisingly found that cholesterol metabolism is highly involved in the NK cell activation by IL-15/2-PEG-PTMC. Following stimulation with IL-15/2-PEG-PTMC or IL-15, NK cells undergo a series of cholesterol metabolism reprogramming, which elevates the cholesterol levels on NK cell membrane. This in turn promotes the formation of lipid rafts and activates immune synapses, effectively contributing to the enhancement of NK cell's antitumor activity. It is believed that it will open a new avenue for improving the efficacy of NK cell immunotherapy by regulating cholesterol metabolism.

Engineering Immunomodulatory Stents Using Zinc Ion-Lysozyme Nanoparticle Platform for Vascular Remodeling

Rapid endothelialization of cardiovascular materials can enhance the vascular remodeling performance. In this work, we developed a strategy for amyloid-like protein-assembly-mediated interfacial engineering to functionalize a biomimetic nanoparticle coating (BMC). Various groups (e.g., hydroxyl and carboxyl) on the BMC are responsible for chelating Zn2+ ions at the stent interface, similar to the glutathione peroxidase-like enzymes found in vivo. This design could reproduce the release of therapeutic nitric oxide gas (NO) and an aligned microenvironment nearly identical with that of natural vessels. In a rabbit abdominal aorta model, BMC-coated stents promoted vascular healing through rapid endothelialization and the inhibition of intimal hyperplasia in the placement sites at 4, 12, and 24 weeks. Additionally, better anticoagulant activity and immunomodulation in the BMC stents were also confirmed, and vascular healing was mainly dependent on cell signaling through the cyclic guanosine monophosphate-protein kinase G (cGMP-PKG) cascade. Overall, a metal-polypeptide-coated stent was developed on the basis of its detailed molecular mechanism of action in vascular remodeling.

Research Progress of Neutrophil-Mediated Drug Delivery Strategies for Inflammation-Related Disease

As the most abundant white blood cells in humans, neutrophils play a key role in acute and chronic inflammation, suggesting that these cells are a key component of targeted therapies for various inflammation-related diseases. Specific enzyme-responsive or specific ligand-modified polymer nanoparticles are beneficial for improving drug efficacy, reducing toxicity, and enhancing focal site retention. However, there remain significant challenges in biomedical applications of these synthetic polymer nanoparticles, mainly due to their rapid clearance by the reticuloendothelial system. In recent years, biomimetic drug delivery systems such as neutrophils acting directly as drug carriers or neutrophil-membrane-coated nanoparticles have received increasing attention due to the natural advantages of neutrophils. Thus, neutrophil-targeted, neutrophil-assisted, or neutrophil-coated nanoparticles exhibit a prolonged blood circulation time and improved accumulation at the site of inflammation. Despite recent advancements, further clinical research must be performed to evaluate neutrophil-based delivery systems for future biomedical application in the diagnosis and treatment of related inflammatory diseases. In this review, we have summarized new exciting developments and challenges in neutrophil-mediated drug delivery strategies for treating inflammation-related diseases.

Biodegradable polymeric nanoparticles increase risk of cardiovascular diseases by inducing endothelium dysfunction and inflammation

Biodegradable polymers are expected to be an alternative to plastics. Because of its high biocompatibility, poly (lactic-co-glycolic acid) (PLGA) is widely used in medicine. It has been reported that micro-nano plastics can be accumulated in the circulatory system and cause tissue injury. With the increasing environmental exposure of degradable polymer nanoparticles (NPs), the impact of this risk factor on cardiovascular disease deserves attention. Thus, we aim to study the harmful effect of PLGA NPs on the process of vascular stenosis which is a typical pathological feature of cardiovascular diseases. We establish a mouse vascular stenosis model with intravenously injecting of PLGA NPs for 2 weeks. This model leads to a significant narrowing of the left common carotid artery which is characterized by the increasing intima area and focal stenosis. We observe that PLGA NPs accelerate stenosis progression by inducing inflammation and impairing vascular function. It promotes the proliferation of smooth muscle cells and causes abnormal collagen distribution. The combination of wall shear stress and PLGA NPs uptake speed up endothelial cell damage, decrease endothelial permeability and cell migration capacity. Our results suggest that PLGA NPs may pose a risk in cardiovascular stenosis which inspire us to concern the biodegradable polymeric materials in our living especially the clinic applications.

Self-Therapeutic Nanomaterials: Applications in Biology and Medicine

Over past decades, nanotechnology has contributed to the biomedical field in areas including detection, diagnosis, and drug delivery via opto-electronic properties or enhancement of biological effects. Though generally considered inert delivery vehicles, a plethora of past and present evidence demonstrates that nanomaterials also exude unique intrinsic biological activity based on composition, shape, and surface functionalization. These intrinsic biological activities, termed self-therapeutic properties, take several forms, including mediation of cell-cell interactions, modulation of interactions between biomolecules, catalytic amplification of biochemical reactions, and alteration of biological signal transduction events. Moreover, study of biomolecule-nanomaterial interactions offers a promising avenue for uncovering the molecular mechanisms of biology and the evolution of disease. In this review, we observe the historical development, synthesis, and characterization of self-therapeutic nanomaterials. Next, we discuss nanomaterial interactions with biological systems, starting with administration and concluding with elimination. Finally, we apply this materials perspective to advances in intrinsic nanotherapies across the biomedical field, from cancer therapy to treatment of microbial infections and tissue regeneration. We conclude with a description of self-therapeutic nanomaterials in clinical trials and share our perspective on the direction of the field in upcoming years.

Recent advances of natural and bioengineered extracellular vesicles and their application in vascular regeneration

The progression of cardiovascular diseases such as atherosclerosis and myocardial infarction leads to serious vascular injury, highlighting the urgent need for targeted regenerative therapy. Extracellular vesicles (EVs) composed of a lipid bilayer containing nuclear and cytosolic materials are relevant to the progression of cardiovascular diseases. Moreover, EVs can deliver bioactive cargo in pathological cardiovascular and regulate the biological function of recipient cells, such as inflammation, proliferation, angiogenesis and polarization. However, because the targeting and bioactivity of natural EVs are subject to several limitations, bioengineered EVs have achieved wide advancements in biomedicine. Bioengineered EVs involve three main ways to acquire including (i) modification of the EVs after isolation; (ii) modification of producer cells before EVs’ isolation; (iii) synthesize EVs using natural or modified cell membranes, and encapsulating drugs or bioactive molecules into EVs. In this review, we first summarize the cardiovascular injury-related disease and describe the role of different cells and EVs in vascular regeneration. We also discuss the application of bioengineered EVs from different producer cells to cardiovascular diseases. Finally, we summarize the surface modification on EVs which can specifically target abnormal cells in injured vascular.

Nanoparticle Effects on Stress Response Pathways and Nanoparticle-Protein Interactions

Nanoparticles (NPs) are increasingly used in a wide variety of applications and products; however, NPs may affect stress response pathways and interact with proteins in biological systems. This review article will provide an overview of the beneficial and detrimental effects of NPs on stress response pathways with a focus on NP-protein interactions. Depending upon the particular NP, experimental model system, and dose and exposure conditions, the introduction of NPs may have either positive or negative effects. Cellular processes such as the development of oxidative stress, the initiation of the inflammatory response, mitochondrial function, detoxification, and alterations to signaling pathways are all affected by the introduction of NPs. In terms of tissue-specific effects, the local microenvironment can have a profound effect on whether an NP is beneficial or harmful to cells. Interactions of NPs with metal-binding proteins (zinc, copper, iron and calcium) affect both their structure and function. This review will provide insights into the current knowledge of protein-based nanotoxicology and closely examines the targets of specific NPs.

Nano-Enabled Reposition of Proton Pump Inhibitors for TLR Inhibition: Toward A New Targeted Nanotherapy for Acute Lung Injury

Toll-like receptor (TLR) activation in macrophages plays a critical role in the pathogenesis of acute lung injury (ALI). While TLR inhibition is a promising strategy to control the overwhelming inflammation in ALI, there still lacks effective TLR inhibitors for clinical uses to date. A unique class of peptide-coated gold nanoparticles (GNPs) is previously discovered, which effectively inhibited TLR signaling and protected mice from lipopolysaccharide (LPS)-induced ALI. To fast translate such a discovery into potential clinical applicable nanotherapeutics, herein an elegant strategy of "nano-enabled drug repurposing" with "nano-targeting" is introduced to empower the existing drugs for new uses. Combining transcriptome sequencing with Connectivity Map analysis, it is identified that the proton pump inhibitors (PPIs) share similar mechanisms of action to the discovered GNP-based TLR inhibitor. It is confirmed that PPIs (including omeprazole) do inhibit endosomal TLR signaling and inflammatory responses in macrophages and human peripheral blood mononuclear cells, and exhibits anti-inflammatory activity in an LPS-induced ALI mouse model. The omeprazole is then formulated into a nanoform with liposomes to enhance its macrophage targeting ability and the therapeutic efficacy in vivo. This research provides a new translational strategy of nano-enabled drug repurposing to translate bioactive nanoparticles into clinically used drugs and targeted nano-therapeutics for ALI.

Inspirations of Cobalt Oxide Nanoparticle Based Anticancer Therapeutics

Cobalt is essential to the metabolism of all animals due to its key role in cobalamin, also known as vitamin B12, the primary biological reservoir of cobalt as an ultra-trace element. Current cancer treatment strategies, including chemotherapy and radiotherapy, have been seriously restricted by their side effects and low efficiency for a long time, which urges us to develop new technologies for more effective and much safer anticancer therapies. Novel nanotechnologies, based on different kinds of functional nanomaterials, have been proved to act as effective and promising strategies for anticancer treatment. Based on the important biological roles of cobalt, cobalt oxide nanoparticles (NPs) have been widely developed for their attractive biomedical applications, especially their potential for anticancer treatments due to their selective inhibition of cancer cells. Thus, more and more attention has been attracted to the preparation, characterization and anticancer investigation of cobalt oxide nanoparticles in recent years, which is expected to introduce novel anticancer treatment strategies. In this review, we summarize the synthesis methods of cobalt oxide nanoparticles to discuss the advantages and restrictions for their preparation. Moreover, we emphatically discuss the anticancer functions of cobalt oxide nanoparticles as well as their underlying mechanisms to promote the development of cobalt oxide nanoparticles for anticancer treatments, which might finally benefit the current anticancer therapeutics based on functional cobalt oxide nanoparticles.

Engineered bioresponsive nanotherapeutics: recent advances in the treatment of atherosclerosis and ischemic-related disease

Biological stimuli that are present during the pathogenesis of disease have gained considerable interest as a critical element for the design of smart drug delivery systems. Recently, the utilization of biological stimuli-responsive (bioresponsive) nanotheranostic agents to treat atherosclerosis and ischemic-related diseases has demonstrated significant outcomes in preclinical studies. Those diseases share similar hallmarks, including high levels of endogenous reactive oxygen species (ROS), low pH, and high enzyme activity. Interestingly, other relevant biological stimuli such as shear stress, cholesterol, and glutathione have recently been explored as internal stimuli to trigger drug release and some particular actions. In addition, a number of strategies can be proposed to enhance their targeting efficiency, diagnostic properties, and efficacy rate. This review discusses recent advancements in the preclinical studies of bioresponsive nanotherapeutics as diagnostic and therapeutic agents against atherosclerosis and ischemic-related diseases as well as some potential strategies to overcome the current limitations.

Phagocytosis of polymeric nanoparticles aided activation of macrophages to increase atherosclerotic plaques in ApoE-/- mice

The unique physiochemical properties of nanomaterials have been widely used in drug delivery systems and diagnostic contrast agents. The safety issues of biomaterials with exceptional biocompatibility and hemo-compatibility have also received extensive attention at the nanoscale, especially in cardiovascular disease. Therefore, we conducted a study of the effects of poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) on the development of aortic atherosclerotic plaques in ApoE^−/− mice. The particle size of PLGA NPs was 92.69 ± 3.1 nm and the zeta potential were − 31.6 ± 2.8 mV, with good blood compatibility. ApoE^−/− mice were continuously injected with PLGA NPs intravenously for 4 and 12 weeks. Examination of oil red O stained aortic sinuses confirmed that the accumulation of PLGA NPs caused a significantly higher extension of atherosclerotic plaques and increasing the expression of associated inflammatory factors, such as TNF-α and IL-6. The combined exposure of ox-LDL and PLGA NPs accelerated the conversion of macrophages to foam cells. Our results highlight further understanding the interaction between PLGA NPs and the atherosclerotic plaques, which we should consider in future nanomaterial design and pay more attention to the process of using nano-medicines on cardiovascular diseases.

Modulation of Innate Immune Toxicity by Silver Nanoparticle Exposure and the Preventive Effects of Pterostilbene

Silver nanoparticles pose a potential risk to ecosystems and living organisms due to their widespread use in various fields and subsequent gradual release into the environment. Only a few studies have investigated the effects of silver nanoparticles (AgNPs) toxicity on immunological functions. Furthermore, these toxic effects have not been fully explored. Recent studies have indicated that zebrafish are considered a good alternative model for testing toxicity and for evaluating immunological toxicity. Therefore, the purpose of this study was to investigate the toxicity effects of AgNPs on innate immunity using a zebrafish model and to investigate whether the natural compound pterostilbene (PTE) could provide protection against AgNPs-induced immunotoxicity. Wild type and neutrophil- and macrophage-transgenic zebrafish lines were used in the experiments. The results indicated that the exposure to AgNPs induced toxic effects including death, malformation and the innate immune toxicity of zebrafish. In addition, AgNPs affect the number and function of neutrophils and macrophages. The expression of immune-related cytokines and chemokines was also affected. Notably, the addition of PTE could activate immune cells and promote their accumulation in injured areas in zebrafish, thereby reducing the damage caused by AgNPs. In conclusion, AgNPs may induce innate immune toxicity and PTE could ameliorate this toxicity.