Silver nanoparticles and silver ions cause inflammatory response through induction of cell necrosis and the release of mitochondria in vivo and in vitro

Bacteriostatic, silver-doped, zirconia-based thin coatings for temporary fixation devices tuning stem cells' expression of adhesion-relevant genes and proteins

Temporary fixation devices must support bone healing, be easily removed without bone tissue overgrowth, and reduce the risk of infection. To match these needs, mechanically and chemically stable thin coatings, based on a zirconia matrix doped with silver (ZrO2-Ag), were sputtered on Ti6Al4V. Coatings with two silver concentrations were produced: a low (0.2 % at Ag) concentration (AL) for bacteriostatic effect and a high (0.5 % at Ag) concentration (AH) for antibacterial properties. Surfaces were characterized for silver content and release, mechanical adhesion, morphology, roughness, wettability, and surface zeta potential, reporting high stability and a continuous Ag release over 28 days. Direct cytocompatibility was shown for human mesenchymal stem cells (hMSC), while antibacterial properties were verified towards Staphylococcus aureus. Results revealed non-toxic and anti-adhesion effects of AL that were deeply investigated towards hMSC by a multi-omics approach. Transcriptomics revealed a down-regulation of cadherins- and integrins-related genes involved in the cell-to-cell and cell-to-substrate adhesion, whereas proteomics confirmed a reduced expression of adhesion proteins (Talin and Ras homolog family member A - RhoA). The OMICS profiles were matched by bioinformatics analysis, confirming a cluster of preserved biological functions strongly related to the cells' adhesion but not to apoptosis. Therefore, AL is a good candidate for bone temporary fixation devices, not interfering with bone healing (cytocompatible), avoiding bone adhesion on the implant surface, and being bacteriostatic.

Biosynthesized Calcium Peroxide Nanoparticles as a Multifunctional Platform for Liver Cancer Therapy

To overcome the limitations associated with chemically synthesized nanoparticles in cancer therapy, researchers have increasingly focused on developing nanoparticles with superior biocompatibility and prolonged tumor retention using biosynthetic methods. In this study, we first identified the presence of calcium peroxide nanoparticles (CaO2 NPs) in the blood of individuals who had ingested calcium gluconate. Furthermore, the dropwise addition of calcium gluconate to human serum resulted in the spontaneous self-assembly of CaO2 NPs. Next, following tail vein injection of fluorescently labeled CaO2 NPs into subcutaneous tumor-bearing nude mice, we observed that the nanoparticles exhibited prolonged accumulation at the tumor sites compared to other organs through visible-light imaging. Immunofluorescence staining demonstrated that CaO2 NPs co-localized with vesicular transport-associated proteins, such as PV-1 and Caveolin-1, as well as the albumin-binding-associated protein SPARC, suggesting that their transport from tumor blood vessels to the tumor site is mediated by Caveolin-1- and SPARC-dependent active transport pathways. Additionally, the analysis of various organs in normal mice injected with CaO2 NPs at concentrations significantly higher than the experimental dose showed no apparent organ damage. Hemolysis assays indicated that hemolysis occurred only at calcium concentrations of 300 µg/mL, whereas the experimental concentration remained well below this threshold with no detectable hemolytic activity. In a subcutaneous tumor-bearing nude mouse model, treatment with docetaxel-loaded CaO2 NPs showed a 68.5% reduction in tumor volume compared to free docetaxel (DTX) alone. These novel biosynthetic CaO2 NPs demonstrated excellent biocompatibility, prolonged retention at the tumor site, safety, and drug-loading capability.

Engagement of specific intracellular pathways in the inflammation-based reprotoxicity effect of small-size silver nanoparticles on spermatogonia and spermatocytes invitro cell models

Male infertility is a serious ongoing problem, whose causes have not yet been clearly identified. However, since human exposure to silver nanoparticles (AgNPs) has recently increased due to their beneficial properties, the present study aimed to determine the impact of small-size AgNPs on mouse spermatogonia (GC-1 spg) and spermatocytes [GC-2 spd(ts)] in vitro models as well as the ability of these nanostructures to induce inflammation. The results showed a significant dose- and time-dependent decrease in the metabolic activity in both cell models, which was correlated with an increase in the intracellular ROS level. Moreover, increased activity of caspase-9 and -3, together with enhanced expression of CASP3 and p(S15)-p53 proteins, was detected. Further studies indicated a decrease in ΔΨm after the AgNP-treatment, which proves induction of apoptosis with engagement of an intrinsic pathway. The PARP1 protein expression, the activity and protein expression of antioxidant enzymes, the GSH level, and the increased level of p-ERK1/2 indicate not only the engagement of DNA damage but also the occurrence of oxidative stress. The small-size AgNPs were able to induce inflammation, proved by increased protein expression of NF-κB, p-IκBα, and NLRP3, which indicate damage to spermatogonia and spermatocyte cells. Moreover, the PGC-1α/PPARγ and NRF2/Keap1 pathways were engaged in the observed effect. The spermatogonial cells were characterized by a stronger inflammation-based response to AgNPs, which may be correlated with the TNFα/TRAF2-based pathway. Summarizing, the obtained results prove that AgNPs impair the function of testis-derived cells by inducing the redox imbalance and inflammation process; therefore, these NPs should be carefully implemented in the human environment.

Size and Surface Properties of Functionalized Organosilica Particles Impact Cell-Particle Interactions Including Mitochondrial Activity

Understanding of the interactions between macrophages and multifunctional nanoparticles is important for development of novel macrophage-based immunotherapies. Here, we investigated the effects of fluorescent thiol-organosilica particle size and surface properties on cell-particle interactions, including mitochondrial activity, using the mouse macrophage cell line J774A.1. Three different sizes of thiol-organosilica particles (150, 400, and 680 nm in diameter) containing fluorescein (OS/F150, OS/F400, and OS/F680) and particles surface functionalized with polyethylenimine (PEI) (OS/F150PEI, OS/F400PEI, and OS/F680PEI) were prepared. Flow cytometric analysis, time-lapse imaging, and single-cell analysis of particle uptake and mitochondrial activity of J774A.1 cells demonstrated variations in uptake and kinetics depending on the particle size and surface as well as on each individual cell. Cells treated with OS/F150 and OS/F150PEI showed higher uptake and mitochondrial activity than those treated with other particles. The interaction between endosomes and mitochondria was observed using 3D fluorescent imaging and was characterized by the involvement of iron transport into mitochondria by iron-containing proteins adsorbed on the particle surface. Scanning electron microscopy of the cells treated with the particles revealed alterations in cell membrane morphology, depending on particle size and surface. We performed correlative light and electron microscopy combined with time-lapse and 3D imaging to develop an integrated correlation analysis of particle uptake, mitochondrial activity, and cell membrane morphology in single macrophages. These cell-specific characteristics of macrophages against functional particles and their evaluation methods are crucial for understanding the immunological functions of individual macrophages and developing novel immunotherapies.

Advances in the Toxicity Assessment of Silver Nanoparticles Derived from a Sphagnum fallax Extract for Monolayers and Spheroids

The production of nanomaterials through environmentally friendly methods is a top priority in the sustainable development of nanotechnology. This paper presents data on the synthesis of silver nanoparticles using an aqueous extract of Sphagnum fallax moss at room temperature. The morphology, stability, and size of the nanoparticles were analyzed using various techniques, including transmission electron microscopy, Doppler laser velocimetry, and UV-vis spectroscopy. In addition, Fourier transform infrared spectroscopy was used to analyze the presence of moss metabolites on the surface of nanomaterials. The effects of different concentrations of citrate-stabilized and moss extract-stabilized silver nanoparticles on cell viability, necrosis induction, and cell impedance were compared. The internalization of silver nanoparticles into both monolayers and three-dimensional cells spheroids was evaluated using dark-field microscopy and hyperspectral imaging. An eco-friendly method for the synthesis of silver nanoparticles at room temperature is proposed, which makes it possible to obtain spherical nanoparticles of 20-30 nm in size with high bioavailability and that have potential applications in various areas of human life.

Silver nanoparticles induced synaptic degeneration via Ca2+/CaMKII signal and Drp1-dependent mitochondrial disorder in HT22 cells

Silver nanoparticles (AgNPs) have been widely used in biomedicine and cosmetics, increasing their potential risks in neurotoxicity. But the involved molecular mechanism remains unclear. This study aims to explore molecular events related to AgNPs-induced neuronal damage by RNA-seq, and elucidate the role of Ca2+/CaMKII signal and Drp1-dependent mitochondrial disorder in HT22 cells synaptic degeneration induced by AgNPs. This study found that cell viabilities were decreased by AgNPs in a dose/time-dependent manner. AgNPs also increased protein expression of PINK1, Parkin, synaptophysin, and inhibited PGC-1α, MAP2 and APP protein expression, indicating AgNPs-induced synaptic degeneration involved in disturbance of mitophagy and mitochondrial biogenesis in HT22 cells. Moreover, inhibition of AgNPs-induced Ca2+/CaMKII activation and Drp1/ROS rescued mitophagy disturbance and synaptic degeneration in HT22 cells by reserving aforementioned protein express changes except for PGC-1α and APP protein. Thus, AgNPs-induced synaptic degeneration was mediated by Ca2+/CaMKII signal and Drp1-dependent mitochondrial disorder in HT22 cells, and mitophagy is the sensitive to the mechanism. Our study will provide in-depth molecular mechanism data for neurotoxic evaluation and biomedical application of AgNPs.

Effect of titanium implants along with silver ions and tetracycline on type I interferon-beta expression during implant-related infections in co-culture and mouse model

Type I interferon-beta (IFN-β) is a crucial component of innate and adaptive immune systems inside the host. The formation of bacterial biofilms on medical implants can lead to inflammatory diseases and implant failure. Biofilms elicit IFN-β production inside the host that, in turn, restrict bacterial growth. Biofilms pose strong antibiotic resistance, whereas surface modification of medical implants with antibacterial agents may demonstrate strong antimicrobial effects. Most of the previous investigations were focused on determining the antibacterial activities of implant surfaces modified with antibacterial agents. The present study, for the first time, measured antibacterial activities and IFN-β expression of titanium surfaces along with silver or tetracycline inside co-culture and mouse models. A periodontal pathogen: Aggregatibacter actinomycetemcomitans reported to induce strong inflammation, was used for infection. Silver and tetracycline were added to the titanium surface using the heat evaporation method. Macrophages showed reduced compatibility on titanium surfaces with silver, and IFN-β expression inside cultured cells significantly decreased. Macrophages showed compatibility on implant surfaces with tetracycline, but IFN-β production significantly decreased inside seeded cells. The decrease in IFN-β production inside macrophages cultured on implant surfaces with silver and tetracycline was not related to the downregulation of Ifn-β gene. Bacterial infection significantly upregulated mRNA expression levels of Isg15, Mx1, Mx2, Irf-3, Irf-7, Tlr-2, Tnf-α, Cxcl-1, and Il-6 genes. Notably, mRNA expression levels of Mx1, Irf7, Tlr2, Tnf-α, Cxcl1, and Il-6 genes inside macrophages significantly downregulated on implant surfaces with silver or tetracycline. Titanium with tetracycline showed higher antibacterial activities than silver. The in vivo evaluation of IFN-β expression around implants was measured inside transgenic mice constitutive for IFN-β expression. Of note, the non-invasive in vivo imaging revealed a significant decrease in IFN-β expression around subcutaneous implants with silver compared to titanium and titanium with tetracycline in sterile or infected situations. The histology of peri-implant tissue interfaces around infected implants with silver showed a thick interface with a significantly higher accumulation of inflammatory cells. Titanium implants with silver and tetracycline remained antibacterial in mice. Findings from this study unequivocally indicate that implant surfaces with silver decrease IFN-β expression, a crucial component of host immunity.

Insights into the toxicological effects of nanomaterials on atherosclerosis: mechanisms involved and influence factors

Atherosclerosis is one of the most common types of cardiovascular disease and is driven by lipid accumulation and chronic inflammation in the arteries, which leads to stenosis and thrombosis. Researchers have been working to design multifunctional nanomedicines with the ability to target, diagnose, and treat atherosclerosis, but recent studies have also identified that nanomaterials can cause atherosclerosis. Therefore, this review aims to outline the molecular mechanisms and physicochemical properties of nanomaterials that promote atherosclerosis. By analyzing the toxicological effects of nanomaterials on cells involved in the pathogenesis of atherosclerosis such as vascular endothelial cells, vascular smooth muscle cells and immune cells, we aim to provide new perspectives for the prevention and treatment of atherosclerosis, and raise awareness of nanotoxicology to advance the clinical translation and sustainable development of nanomaterials.

Structural parameters of nanoparticles affecting their toxicity for biomedical applications: a review

Rapidly growing interest in using nanoparticles (NPs) for biomedical applications has increased concerns about their safety and toxicity. In comparison with bulk materials, NPs are more chemically active and toxic due to the greater surface area and small size. Understanding the NPs' mechanism of toxicity, together with the factors influencing their behavior in biological environments, can help researchers to design NPs with reduced side effects and improved performance. After overviewing the classification and properties of NPs, this review article discusses their biomedical applications in molecular imaging and cell therapy, gene transfer, tissue engineering, targeted drug delivery, Anti-SARS-CoV-2 vaccines, cancer treatment, wound healing, and anti-bacterial applications. There are different mechanisms of toxicity of NPs, and their toxicity and behaviors depend on various factors, which are elaborated on in this article. More specifically, the mechanism of toxicity and their interactions with living components are discussed by considering the impact of different physiochemical parameters such as size, shape, structure, agglomeration state, surface charge, wettability, dose, and substance type. The toxicity of polymeric, silica-based, carbon-based, and metallic-based NPs (including plasmonic alloy NPs) have been considered separately.

Photo-Activable Organosilver Nanosystem Facilitates Synergistic Cancer Theranostics

Anticancer drug development is important for human health, yet it remains a tremendous challenge. Photodynamic therapy (PDT), which induces cancer cell apoptosis via light-triggered production of reactive oxygen species, is a promising method. However, it has minimal efficacy in subcellular targeting, hypoxic microenvironments, and deep-seated malignancies. Here, we constructed a breast cancer photo-activable theranostic nanosystem through the rational design of a synthetic lysosomal-targeted molecule with multifunctions as aggregation-induced near-infrared (NIR) emission, a photosensitizer (PDT), and organosilver (chemotherapy) for NIR imaging and synergistic cancer therapy. The synthetic molecule could self-assemble into nanoparticles (TPIMBS NPs) and be stabilized with amphiphilic block copolymers for enhanced accumulation in tumor sites through passive targeting while reducing the leakage in normal tissues. Through photochemical internalization, TPIMBS NPs preferentially concentrated in the lysosomes of cancer cells and generated reactive oxygen species (ROS) upon light irradiation, resulting in lysosomal rupture and release of PSs to the cytosol, which led to cell apoptosis. Further, the photoinduced release of Ag⁺ from TPIMBS NPs could act as chemotherapy, significantly improving the overall therapeutic efficacy by synergistic effects with PDT. This research sheds fresh light on the creation of effective cancer treatments.

Naringenin attenuates inflammation, apoptosis, and ferroptosis in silver nanoparticle-induced lung injury through a mechanism associated with Nrf2/HO-1 axis: In vitro and in vivo studies

With the wide application of silver nanoparticles (AgNPs), their potential damage to human health needs to be investigated. Lung is one of the main target organs after inhalation of AgNPs. Naringenin has been reported to have anti-inflammatory and anti-oxidative properties. This study aims to evaluate the protective effects of naringenin against AgNPs-induced lung injury and determine the underlying mechanism. In in vivo experiments, AgNPs were intratracheally instilled into ICR mice (l mg/kg) to establish a lung injury model. These mice were then treated with naringenin by oral gavage (25, 50, 100 mg/kg) for three days. Naringenin treatment decreased the levels of white blood cells, neutrophils, and lymphocytes in the blood, ameliorated lung injury, suppressed the release of pro-inflammatory cytokines, normalized ferroptotic markers and prevented oxidative stress with elevating Nrf2 and HO-1 protein expressions in lung. In in vitro experiments, BEAS-2B cells were firstly treated with AgNPs (320 μg/mL) and then naringenin (25, 50, and 100 μM), respectively. Naringenin attenuated AgNPs-induced oxidative stress and inflammatory response. Moreover, naringenin attenuated AgNPs-induced apoptosis with modulated low BAX, CytC, cleaved Caspase9, cleaved Caspase3 but high Bcl2. Furthermore, naringenin effectively decreased ferroptotic markers and increased the protein expressions of Nrf2 and HO-1, as well as increased the nuclear translocation of Nrf2. Importantly, the anti-apoptotic and anti-ferroptotic effects of naringenin in BEAS-2B cells were found to be at least partially Nrf2-dependent. These results indicated that naringenin exerted anti-inflammation, anti-apoptosis, and anti-ferroptosis effects and protected against AgNPs-induced lung injury at least partly via activating Nrf2/HO-1 signaling pathway.

Protective effects of silver nanoparticles in isoproterenol-induced myocardial infarction in rats

Background

Silver nanoparticles (AgNPs) are widely used in the medical field, including cardiovascular. However, limited research has investigated the effect of AgNPs on the protection of myocardial infarction (MI).

Objectives

Isoproterenol (Iso)-induced MI and the cardiac protection offered by AgNPs were investigated in the present study. Additionally, we characterized the profile of Ag in the form of nanoparticles.

Methods

Twenty-four male Wistar rats were randomly divided into four groups as follows: normal, Iso, Iso + AgNO3, and Iso + AgNP groups. AgNPs and silver ion (AgNO3) were administered intraperitoneally at 2.5 mg/kg BW for 14 days. Iso induction was performed using two doses of 85 mg/kg BW given subcutaneously on days 13 and 14. Blood and cardiac tissue samples were taken 24 h after the last dose of Iso and checked for Creatine Kinase-MB (CK-MB), lactate dehydrogenase in plasma along with oxidative stress parameters, mitochondria biogenesis markers, and inflammation representative genes in cardiac tissue. Additionally, we analyzed the histopathological features in cardiac tissue.

Results

The silver was confirmed in the form of nanoparticles by its size at intervals of 8.72-37.84 nm. Both AgNO3 and AgNPs showed similar cardioprotective effects, as shown by the decrease in biochemical markers of cardiac toxicity, namely, CK-MB. Additionally, AgNPs group have better efficacy compared with AgNO3 group in ameliorating Iso-mediated oxidative stress production, as evidenced by the significant decrease in malondialdehyde level and increased superoxide dismutase activity (P < 0.0001 and P < 0.01, respectively) in cardiac tissue compared with the Iso group. Mechanistically, AgNPs, but not AgNO3, enhanced the expression levels of mitochondrial transcription factor A and peroxisome proliferator-activated receptor-gamma coactivator 1-alpha in post-MI heart and reduced the protein expression of nuclear factor-kappa B (NF-κB) assessed by western blot analysis. Furthermore, these results were confirmed with the histopathological evaluation of cardiac tissue. Nevertheless, pretreatment with either AgNO3 or AgNPs improved the aspartate aminotransferase level.

Conclusion

These results suggested that AgNPs have more superior cardioprotective effect compared with AgNO3 against Iso-induced MI, at least in part through amelioration of NF-κB expression level induced by oxidative stress overproduction.

Enhanced silver nanoparticle-induced pulmonary inflammation in a metabolic syndrome mouse model and resolvin D1 treatment

BACKGROUND

Metabolic syndrome (MetS) exacerbates susceptibility to inhalation exposures such as particulate air pollution, however, the mechanisms responsible remain unelucidated. Previously, we determined a MetS mouse model exhibited exacerbated pulmonary inflammation 24 h following AgNP exposure compared to a healthy mouse model. This enhanced response corresponded with reduction of distinct resolution mediators. We hypothesized silver nanoparticle (AgNP) exposure in MetS results in sustained pulmonary inflammation. Further, we hypothesized treatment with resolvin D1 (RvD1) will reduce exacerbations in AgNP-induced inflammation due to MetS.

RESULTS

To evaluate these hypotheses, healthy and MetS mouse models were exposed to vehicle (control) or AgNPs and a day later, treated with resolvin D1 (RvD1) or vehicle (control) via oropharyngeal aspiration. Pulmonary lung toxicity was evaluated at 3-, 7-, 14-, and 21-days following AgNP exposure. MetS mice exposed to AgNPs and receiving vehicle treatment, demonstrated exacerbated pulmonary inflammatory responses compared to healthy mice. In the AgNP exposed mice receiving RvD1, pulmonary inflammatory response in MetS was reduced to levels comparable to healthy mice exposed to AgNPs. This included decreases in neutrophil influx and inflammatory cytokines, as well as elevated anti-inflammatory cytokines.

CONCLUSIONS

Inefficient resolution may contribute to enhancements in MetS susceptibility to AgNP exposure causing an increased pulmonary inflammatory response. Treatments utilizing specific resolution mediators may be beneficial to individuals suffering MetS following inhalation exposures.

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.

LncRNA MEG3 ameliorates NiO nanoparticles-induced pulmonary inflammatory damage via suppressing the p38 mitogen activated protein kinases pathway

The lung inflammatory damage could result from the nickel oxide nanoparticles (NiO NPs), in which the underlying mechanism is still unclear. This article explored the roles of long noncoding RNA maternally expressed gene 3 (lncRNA MEG3) and p38 mitogen activated protein kinases (p38 MAPK) pathway in pulmonary inflammatory injury induced by NiO NPs. Wistar rats were treated with NiO NPs suspensions (0.015, 0.06, and 0.24 mg/kg) by intratracheal instillation twice-weekly for 9 weeks. Meanwhile, A549 cells were treated with NiO NPs suspensions (25, 50, and 100 μg/ml) for 24 h. It can be concluded that the NiO NPs did trigger pulmonary inflammatory damage, which was confirmed by the histopathological examination, abnormal changes of inflammatory cells and inflammatory cytokines (IL-1β, IL-6, TGF-β1, TNF-α, IFN-γ, IL-10, CXCL-1 and CXCL-2) in bronchoalveolar lavage fluid (BALF), pulmonary tissue and cell culture supernatant. Furthermore, NiO NPs activated the p38 MAPK pathway and downregulated MEG3 in vivo and in vitro. However, p38 MAPK pathway inhibitor (10 μM SB203580) reversed the alterations in the expression levels of inflammatory cytokines induced by NiO NPs. Meanwhile, over-expressed MEG3 significantly suppressed NiO NPs-induced p38 MAPK pathway activation and inflammatory cytokines changes. Overall, the above results proved that over-expression of lncRNA MEG3 reduced NiO NPs-induced inflammatory damage by preventing the activation of p38 MAPK pathway.

NiONP-Induced Oxidative Stress and Mitochondrial Impairment in an In Vitro Pulmonary Vascular Cell Model Mimicking Endothelial Dysfunction

The development and use of nanomaterials, especially of nickel oxide nanoparticles (NiONPs), is expected to provide many benefits but also has raised concerns about the potential human health risks. Inhaled NPs are known to exert deleterious cardiovascular side effects, including pulmonary hypertension. Consequently, patients with pulmonary hypertension (PH) could be at increased risk for morbidity. The objective of this study was to compare the toxic effects of NiONPs on human pulmonary artery endothelial cells (HPAEC) under physiological and pathological conditions. The study was conducted with an in vitro model mimicking the endothelial dysfunction observed in PH. HPAEC were cultured under physiological (static and normoxic) or pathological (20% cycle stretch and hypoxia) conditions and exposed to NiONPs (0.5–5 μg/cm²) for 4 or 24 h. The following endpoints were studied: (i) ROS production using CM-H₂DCF-DA and MitoSOX probes, (ii) nitrite production by the Griess reaction, (iii) IL-6 secretion by ELISA, (iv) calcium signaling with a Fluo-4 AM probe, and (v) mitochondrial dysfunction with TMRM and MitoTracker probes. Our results evidenced that under pathological conditions, ROS and nitrite production, IL-6 secretions, calcium signaling, and mitochondria alterations increased compared to physiological conditions. Human exposure to NiONPs may be associated with adverse effects in vulnerable populations with cardiovascular risks.

Disruption of pulmonary resolution mediators contribute to exacerbated silver nanoparticle-induced acute inflammation in a metabolic syndrome mouse model

Pre-existing conditions modulate sensitivity to numerous xenobiotic exposures such as air pollution. Specifically, individuals suffering from metabolic syndrome (MetS) demonstrate enhanced acute inflammatory responses following particulate matter inhalation. The mechanisms associated with these exacerbated inflammatory responses are unknown, impairing interventional strategies and our understanding of susceptible populations. We hypothesize MetS-associated lipid dysregulation influences mediators of inflammatory resolution signaling contributing to increased acute pulmonary toxicity. To evaluate this hypothesis, healthy and MetS mouse models were treated with either 18-hydroxy eicosapentaenoic acid (18-HEPE), 14-hydroxy docosahexaenoic acid (14-HDHA), 17-hydroxy docosahexaenoic acid (17-HDHA), or saline (control) via intraperitoneal injection prior to oropharyngeal aspiration of silver nanoparticles (AgNP). In mice receiving saline treatment, AgNP exposure resulted in an acute pulmonary inflammatory response that was exacerbated in MetS mice. A targeted lipid assessment demonstrated 18-HEPE, 14-HDHA, and 17-HDHA treatments altered lung levels of specialized pro-resolving lipid mediators (SPMs). 14-HDHA and 17-HDHA treatments more efficiently reduced the exacerbated acute inflammatory response in AgNP exposed MetS mice as compared to 18-HEPE. This included decreased neutrophilic influx, diminished induction of inflammatory cytokines/chemokines, and reduced alterations in SPMs. Examination of SPM receptors determined baseline reductions in MetS mice compared to healthy as well as decreases due to AgNP exposure. Overall, these results demonstrate AgNP exposure disrupts inflammatory resolution, specifically 14-HDHA and 17-HDHA derived SPMs, in MetS contributing to exacerbated acute inflammatory responses. Our findings identify a potential mechanism responsible for enhanced susceptibility in MetS that can be targeted for interventional therapeutic approaches.

Nanocomposite Biopolymer Arboblend V2 Nature AgNPs

Due to the pressing problems of today’s world, regarding both the finding of new, environmentally friendly materials which have the potential to replace classic ones, and the need to limit the accelerated spread of bacteria in hospitals, offices and other types of spaces, many researchers have chosen to develop their work in this field. Thus, biopolymeric materials have evolved so much that they are gradually becoming able to remove fossil-based plastics from major industries, which are harmful to the environment and implicitly to human health. The biopolymer employed in the present study, Arboblend V2 Nature with silver nanoparticle content (AgNP) meets both aspects mentioned above. The main purpose of the paper is to replace several parts and products in operation which exhibit antibacterial action, preventing the colonization and proliferation of bacteria (Streptococcus pyogenes and Staphylococcus aureus, by using the submerged cultivation method), but also the possibility of degradation in different environments. The biopolymer characterization followed the thermal behavior of the samples, their structure and morphology through specific analyses, such as TGA (thermogravimetric analysis), DSC (differential scanning calorimetry), SEM (scanning electron microscopy) and XRD (X-ray diffraction). The obtained results offer the possibility of use of said biocomposite material in the medical field because of its antibacterial characteristics that have proved to be positive, and, therefore, suitable for such applications. The thermal degradation and the structure of the material highlighted the possibility of employing it in good conditions at temperatures up to 200 °C. Two types of samples were used for thermal analysis: first, in the form of granules coated with silver nanoparticles, and second, test specimen cut from the sample obtained by injection molding from the coated granules with silver nanoparticles.

Potential biomarkers and targets of mitochondrial dynamics

Mitochondrial dysfunction contributes to the imbalance of cellular homeostasis and the development of diseases, which is regulated by mitochondria-associated factors. The present review aims to explore the process of the mitochondrial quality control system as a new source of the potential diagnostic biomarkers and/or therapeutic targets for diseases, including mitophagy, mitochondrial dynamics, interactions between mitochondria and other organelles (lipid droplets, endoplasmic reticulum, endosomes, and lysosomes), as well as the regulation and posttranscriptional modifications of mitochondrial DNA/RNA (mtDNA/mtRNA). The direct and indirect influencing factors were especially illustrated in understanding the interactions among regulators of mitochondrial dynamics. In addition, mtDNA/mtRNAs and proteomic profiles of mitochondria in various lung diseases were also discussed as an example. Thus, alternations of mitochondria-associated regulators can be a new category of biomarkers and targets for disease diagnosis and therapy.

Effects of Silver Nanoparticles on Proliferation and Apoptosis in Granulosa Cells of Chicken Preovulatory Follicles: An In Vitro Study

The continuous development of poultry production related to the growing demand for eggs and chicken meat makes it necessary to use modern technologies. An answer to this demand may be the use of nanotechnology in poultry farming. One of the promising nanomaterials in this field are silver nanoparticles (AgNPs), which are used as disinfectants, reducing microbial pollution and the amounts of greenhouse gases released. This study aimed to evaluate the effect of AgNPs on the proliferation and apoptosis process in the granulosa cells of chicken preovulatory follicles. The in vitro culture experiment revealed that both 13 nm and 50 nm AgNPs inhibited the proliferation of the granulosa cells. However, a faster action was observed in 50 nm AgNPs than in 13 nm ones. A size-dependent effect of AgNP was also demonstrated for the caspase-3 activity. AgNPs 13 nm in size increased the caspase-3 activity in granulosa cells, while 50 nm AgNPs did not exert an effect, which may indicate the induction of distinct cell death pathways by AgNPs. In conclusion, our study reveals that AgNPs in vitro inhibit granulosa cell proliferation and stimulate their apoptosis. These results suggest that AgNPs may disrupt the final stage of preovulatory follicle maturation and ovulation.

BTK Promotes Atherosclerosis by Regulating Oxidative Stress, Mitochondrial Injury, and ER Stress of Macrophages

Atherosclerosis (AS) is a chronic metabolic disease in arterial walls, characterized by lipid deposition and persistent aseptic inflammation. AS is regarded as the basis of a variety of cardiovascular and cerebrovascular diseases. It is widely acknowledged that macrophages would become foam cells after internalizing lipoprotein particles, which is an initial factor in atherogenesis. Here, we showed the influences of Bruton's tyrosine kinase (BTK) in macrophage-mediated AS and how BTK regulates the inflammatory responses of macrophages in AS. Our bioinformatic results suggested that BTK was a potential hub gene, which is closely related to oxidative stress, ER stress, and inflammation in macrophage-induced AS. Moreover, we found that BTK knockdown could restrain ox-LDL-induced NK-κB signaling activation in macrophages and repressed M1 polarization. The mechanistic studies revealed that oxidative stress, mitochondrial injury, and ER stress in macrophages were also suppressed by BTK knockdown. Furthermore, we found that sh-BTK adenovirus injection could alleviate the severity of AS in ApoE-/- mice induced by a high-fat diet in vivo. Our study suggested that BTK promoted ox-LDL-induced ER stress, oxidative stress, and inflammatory responses in macrophages, and it may be a potential therapeutic target in AS.

PAMAM dendrimers with dual-conjugated vancomycin and Ag-nanoparticles do not induce bacterial resistance and kill vancomycin-resistant Staphylococci

The effective life-time of new antimicrobials until the appearance of the first resistant strains is steadily decreasing, which discourages incentives for commercialization required for clinical translation and application. Therefore, development of new antimicrobials should not only focus on better and better killing of antimicrobial-resistant strains, but as a paradigm shift on developing antimicrobials that prevent induction of resistance. Heterofunctionalized, poly-(amido-amine) (PAMAM) dendrimers with amide-conjugated vancomycin (Van) and incorporated Ag nanoparticles (AgNP) showed a 6-7 log reduction in colony-forming-units of a vancomycin-resistant Staphylococcus aureus strain in vitro, while not inducing resistance in a vancomycin-susceptible strain. Healing of a superficial wound in mice infected with the vancomycin-resistant S. aureus was significantly faster and more effective by irrigation with low-dose, dual-conjugated Van-PAMAM-AgNP dendrimer suspension than by irrigation with vancomycin in solution or a PAMAM-AgNP dendrimer suspension. Herewith, dual-conjugation of vancomycin together with AgNPs in heterofunctionalized PAMAM dendrimers fulfills the need for new, prolonged life-time antimicrobials killing resistant pathogens without inducing resistance in susceptible strains. Important for clinical translation, this better use of antibiotics can be achieved with currently approved and clinically applied antibiotics, provided suitable for amide-conjugation.

Current understanding of nanoparticle toxicity mechanisms and interactions with biological systems

Nanotechnology is an emerging science involving the manipulation of matter on the nanometer scale.