Silica nanoparticles induce lung inflammation in mice via ROS/PARP/TRPM2 signaling-mediated lysosome impairment and autophagy dysfunction

LC3B-regulated autophagy mitigates zinc oxide nanoparticle-induced epithelial cell dysfunction and acute lung injury

Zinc oxide nanoparticles (ZnONPs) are widely utilized across various industries, raising concerns about their potential toxicity, especially in the respiratory system. This study explores the role of autophagy, regulated by microtubule-associated protein 1A/1B-light chain 3B (LC3B), in ZnONPs-induced toxicity using both in vivo (LC3B knockout mice) and in vitro (BEAS-2B cells) models. Our findings demonstrate that LC3B-regulated autophagy mitigates ZnONPs-induced epithelial cell dysfunction and acute lung injury. In the absence of LC3B, oxidative stress, inflammation, and intracellular zinc accumulation are exacerbated, resulting in mitochondrial dysfunction and epithelial cell death. In vitro, LC3B knockdown disrupted zinc ion transporter expression and impaired mitophagic flux in BEAS-2B cells. Treatment with zinc ion chelators alleviated these toxic effects, confirming that free zinc ions play a critical role in driving ZnONPs toxicity. These findings highlight that targeting autophagy and maintaining zinc homeostasis could offer therapeutic strategies to reduce ZnONPs-induced lung damage.

Quercetin Protects against Silicon dioxide Particles-induced spleen ZBP1-Mediated PANoptosis by regulating the Nrf2/Drp1/mtDNA axis

Silicon dioxide particles (SiO2) are a widely used novel material, and SiO2 that enter the body can accumulate in the spleen and cause spleen injury. Quercetin (Que) has a strong antioxidant activity and can also regulate and improve immune function, but whether Que can improve SiO2-induced spleen injury and its underlying mechanism remain to be explored. Herein, we established a C57BL/6 mice model with SiO2 exposure (10 mg/kg) and treated with Que (25 mg/kg). We also cultured CTLL-2 cells for in vitro experiments. Studies in vivo and in vitro showed that SiO2 exposure caused oxidative stress and mitochondrial dynamics disorder, which led to decrease of mitochondrial membrane potential (ΔΨm) and mitochondrial DNA (mtDNA) leakage. mtDNA was recognized by Z-DNA binding protein 1 (ZBP1) in the cytoplasm and increased the expression of ZBP1. This process further promoted the assembly of the ZBP1-mediated PANoptosome, which subsequently induced PANoptosis. Interestingly, supplementation with Que significantly reversed these changes. Specifically, Que mitigated spleen ZBP-1 mediated PANoptosis through preventing mtDNA leakage via regulating nuclear factor erythroid 2-related factor 2/reactive oxygen species/dynamin-related protein 1 (Nrf2/ROS/Drp1) axis. This study enriches the understanding of the toxicological mechanisms of SiO2 and provides evidence for the protective effects of Que against SiO2-induced splenic toxicity.

Review on the role of autophagy in the toxicity of nanoparticles and the signaling pathways involved

As the development of nanotechnology, the application of nanoproducts and the advancement of nanomedicine, the contact of nanoparticles (NPs) with human body is becoming increasingly prevalent. This escalation elevates the risk of NPs exposure for workers, consumers, researchers, and both aquatic and terrestrial organisms throughout the production, usage, and disposal stages. Consequently, evaluating nanotoxicity remains critically important, though standardized assessment criteria are still lacking. The diverse and complex properties of NPs further complicate the understanding of their toxicological mechanisms. Autophagy, a fundamental cellular process, exhibits dual functions-both pro-survival and pro-death. This review offers an updated perspective on the dual roles of autophagy in nanotoxicity and examines the factors influencing autophagic responses. However, no definitive framework exists for predicting NPs-induced autophagy. Beyond the conventional autophagy pathways, the review highlights specific transcription factors activated by NPs and explores metabolic reprogramming. Particular attention is given to NPs-induced selective autophagy, including mitophagy, ER-phagy, ferritinophagy, lysophagy, and lipophagy. Additionally, the review investigates autophagy's involvement in NPs-mediated biological processes such as ferroptosis, inflammation, macrophage polarization, epithelial-mesenchymal transition, tumor cell proliferation and drug resistance, as well as liver and kidney injury, neurotoxicity, and other diseases. In summary, this review presents a novel update on selective autophagy-mediated nanotoxicity and elucidates the broader interactions of autophagy in NPs-induced biological processes. Collectively, these insights offer valuable strategies for mitigating nanotoxicity through autophagy modulation and advancing the development of NPs in biomedical applications.

Short- and long-term pathologic responses to quartz are induced by nearly free silanols formed during crystal fracturing

BACKGROUND

Inhalation of respirable crystalline silica particles, including quartz, is associated with an increased risk of developing pathologies, including persistent lung inflammation, fibrosis, cancer, and systemic autoimmunity. We demonstrated that the nearly free silanols (NFS) generated upon quartz fracturing trigger the early molecular events determining quartz toxicity. Here, we address the involvement of NFS in driving short- and long-term pathogenic responses, including lung inflammation, fibrosis, cancer, and autoimmunity in multiple mouse models.

RESULTS

In vivo pulmonary responses to as-grown NFS-poor quartz (gQ) and fractured NFS-rich quartz (gQ-f) of synthetic origin were compared to two NFS-rich reference quartz dusts (Min-U-Sil 5, mQ-f). Acute and persistent inflammation, as well as fibrosis, were assessed 3 and 60 days, respectively, after administering one dose of particles (2 mg) via oropharyngeal aspiration (o.p.a.) to C57BL/6 mice. The carcinogenic potential was assessed in a co-carcinogenicity study using A/J mice, which were pre-treated with 3-methylcholanthrene (3-MC) and administered four doses of quartz particles (4 × 1 mg, o.p.a.), then sacrificed after 10 months. Autoimmunity was evaluated in autoimmune-prone 129/Sv mice 4 months after particle administration (2 × 1.25 mg, o.p.a). Mice exposed to NFS-rich quartz exhibited a strong acute lung inflammatory response, characterized by pro-inflammatory cytokine release and leukocyte accumulation, which persisted for up to 60 days. No inflammatory effect was observed in mice treated with NFS-poor gQ. Fibrosis onset (i.e., increased levels of pro-fibrotic factors, hydroxyproline, and collagen) was prominent in mice exposed to NFS-rich but not to NFS-poor quartz. Additionally, lung cancer development (tumour numbers) and autoimmune responses (elevated IgG and anti-dsDNA autoantibody levels) were only observed after exposure to NFS-rich quartz.

CONCLUSIONS

Collectively, the results indicate that NFS, which occur upon fracturing of quartz particles, play a crucial role in the short- and long-term local and systemic responses to quartz. The assessment of NFS on amorphous or crystalline silica particles may help create a predictive model of silica pathogenicity.

Localization of silica nanoparticles to lysosome causes lysosomal dysfunction in JEG-3 cells

Nanoparticles have useful functions due to the characteristics conferred on them by an increase in their specific surface area, and they have already been put into practical use in products in various industrial fields. Although exposure to nanoparticles in daily life is unavoidable for pregnant women, studies that evaluate the toxicity of nanoparticles in pregnant women are lacking. To redress this, we have focused on the placenta and have previously revealed that nanoparticles can show placental toxicity. However, there is still little knowledge regarding the behavior of nanoparticles within placental cells, which would enable us to understand their mode of action. Here, we tried to clarify the intracellular localization of silica nanoparticles in placental cells and how this affects placental toxicity. We analyzed the uptake of silica nanoparticles with a diameter of 10 nm (nSP10) into JEG-3 cells, a human choriocarcinoma cell line. Flow cytometry analysis showed that nSP10 labelled with red fluorescence were taken up into JEG-3 cells, and that pre-treatment with the endocytosis inhibitor cytochalasin D inhibited their uptake, suggesting that nSP10 are taken up into JEG-3 cells by the endocytic pathway. Moreover, confocal microscopy revealed that nSP10 are prominently localized in lysosomes. Staining with LysoTracker showed that nSP10 treatment increased the acidic compartment of JEG-3 cells, suggesting lysosome accumulation and swelling. These results indicate that nSP10 taken into placental cells are transferred to lysosomes and may cause lysosomal dysfunction.

Antimicrobial Feature of Nanoparticles in the Antibiotic Resistance Era: From Mechanism to Application

The growth of nanoscale sciences enables us to define and design new methods and materials for a better life. Health and disease prevention are the main issues in the human lifespan. Some nanoparticles (NPs) have antimicrobial properties that make them useful in many applications. In recent years, NPs have been used as antibiotics to overcome drug resistance or as drug carriers with antimicrobial features. They can also serve as antimicrobial coatings for implants in different body areas. The antimicrobial feature of NPs is based on different mechanisms. For example, the oxidative functions of NPs can inhibit nucleic acid replication and destroy the microbial cell membrane as well as interfere with their cellular functions and biochemical cycles. On the other hand, NPs can disrupt the pathogens' lifecycle by interrupting vital points of their life, such as virus uncoating and entry into human cells. Many types of NPs have been tested by different scientists for these purposes. Silver, gold, copper, and titanium have shown the most ability to inhibit and remove pathogens inside and outside the body. In this review, the authors endeavor to comprehensively describe the antimicrobial features of NPs and their applications for different biomedical goals.

Toxicity study of silica nanoparticles following 94-day repeated oral administration in Sprague Dawley rats

This study was designed to investigate the toxic response of Sprague Dawley (SD) rats following oral administration of different doses of silica nanoparticles (SiNPs) for 94 consecutive days, as well as the recovery after 30 days of withdrawal. Rats were orally administered SiNPs at dosages of 0, 125, 250, and 500 mg/kg /day once a day for 94 continuous days. By the end of the study, there were no fatalities in any of the experimental animals that received SiNPs orally. Under the tested doses, no adverse effects related to SiNPs treatment were observed in a comprehensive assessment of several dimensions, including clinical signs, body weight changes, food consumption, hematological parameters, blood biochemical indices, urinalysis, organ weights and coefficients, and gross and histopathology. Based on the current study results, the No Observed Adverse Effect Level (NOAEL) for repeated oral administration of SiNPs in rats for 94 consecutive days was designated as 500 mg/kg/day.

Unexpected Inhibitory Role of Silica Nanoparticles on Lung Cancer Development by Promoting M1 Polarization of Macrophages

Introduction

Inhalation exposure to silica nanoparticles (SiNPs) is frequently inevitable in modern times. Although the impact of SiNPs on the ecological niche of the lungs has been extensively explored, the role and mechanism of SiNPs in the microenvironment of lung tumors remain elusive.

Methods

In this investigation, Lewis lung carcinoma (LLC) was implanted into the left lung in situ after 28 days of intratracheal SiNPs injection into the lungs of mice. This study evaluates the effects of SiNPs on the tumor immune microenvironment both in vitro and in vivo. Our findings indicate that SiNPs can suppress lung cancer by modulating the immune microenvironment of tumors.

Results

SiNPs treatment promotes macrophage M1 polarization by activating both NF-κB pathway and glycolytic mechanisms. This phenomenon may be associated with lung inflammation and fluctuation in the pre-metastatic and metastatic microenvironments induced by SiNPs exposure in mice. Additionally, we have shown for the first time that SiNPs have an inhibitory effect on lung carcinogenesis and its progression.

Conclusion

This study uniquely demonstrates that SiNPs suppress lung cancer by promoting M1 polarization of macrophages in the immune microenvironment of lung tumors. Our findings are critical in exploring the interaction between SiNPs and lung cancer.

Late-onset major depressive disorder: exploring the therapeutic potential of enhancing cerebral brain-derived neurotrophic factor expression through targeted microRNA delivery

Major depressive disorder (MDD) is a severe psychiatric condition that significantly impacts the overall quality of life. Although MDD can occur across all age groups, it is notably prevalent among older individuals, with the aggravating circumstance that the clinical condition is frequently overlooked and undertreated. Furthermore, older adults often encounter resistance to standard treatments, experience adverse events, and face challenges associated with polypharmacy. Given that late-life MDD is associated with heightened rates of disability and mortality, as well as imposing a significant economic and logistical burden on healthcare systems, it becomes imperative to explore novel therapeutic approaches. These could serve as either supplements to standard guidelines or alternatives for non-responsive patients, potentially enhancing the management of geriatric MDD patients. This review aims to delve into the potential of microRNAs targeting Brain-Derived Neurotrophic Factor (BDNF). In MDD, a significant decrease in both central and peripheral BDNF has been well-documented, raising implications for therapy response. Notably, BDNF appears to be a key player in the intricate interplay between microRNA-induced neuroplasticity deficits and neuroinflammation, both processes deeply implicated in the onset and progression of the disease. Special emphasis is placed on delivery methods, with a comprehensive comparison of the strengths and weaknesses of each proposed approach. Our hypothesis proposes that employing multiple microRNAs concurrently, with the ability to directly influence BDNF and activate closely associated pathways, may represent the most promising strategy. Regarding vehicles, although the perfect nanoparticle remains elusive, considering the trade-offs, liposomes emerge as the most suitable option.

Lysosomal dysfunction-derived autophagy impairment of gingival epithelial cells in diabetes-associated periodontitis with altered protein acetylation

Diabetes-associated periodontitis (DP) presents severe inflammation and resistance to periodontal conventional treatment, presenting a significant challenge in clinical management. In this study, we investigated the underlying mechanism driving the hyperinflammatory response in gingival epithelial cells (GECs) of DP patients. Our findings indicate that lysosomal dysfunction under high glucose conditions leads to the blockage of autophagy flux, exacerbating inflammatory response in GECs. Single-cell RNA sequencing and immunohistochemistry analyses of clinical gingival epithelia revealed dysregulation in the lysosome pathway characterized by reduced levels of lysosome-associated membrane glycoprotein 2 (LAMP2) and V-type proton ATPase 16 kDa proteolipid subunit c (ATP6V0C) in subjects with DP. In vitro stimulation of human gingival epithelial cells (HGECs) with a hyperglycemic microenvironment showed elevated release of proinflammatory cytokines, compromised lysosomal acidity and blocked autophagy. Moreover, HGECs with deficiency in ATP6V0C demonstrated impaired autophagy and heightened inflammatory response, mirroring the effects of high glucose stimulation. Proteomic analysis of acetylation modifications identified altered acetylation levels in 28 autophagy-lysosome pathway-related proteins and 37 sites in HGECs subjected to high glucose stimulation or siATP6V0C. Overall, our finding highlights the pivotal role of lysosome impairment in autophagy obstruction in DP and suggests a potential impact of altered acetylation of relevant proteins on the interplay between lysosome dysfunction and autophagy blockage. These insights may pave the way for the development of effective therapeutic strategies against DP.

Understanding the role of swirling flow in dry powder inhalers: Implications for design considerations and pulmonary delivery

Dry powder inhalers (DPIs) are widely employed to treat respiratory diseases, offering numerous advantages such as high dose capacity and stable formulations. However, they usually face challenges in achieving sufficient pulmonary drug delivery and minimizing excessive oropharyngeal deposition. This review provides a new viewpoint to address these challenges by focusing on the role of swirling flow, a crucial yet under-researched aspect that induces strong turbulence. In the review, we comprehensively discuss both key classic designs (tangential inlet, swirling chamber, grid mesh, and mouthpiece) and innovative designs in inhalers, exploring how the induced swirling flow initiates powder dispersion and promotes delivery efficiency. Valuable design considerations to effectively coordinate inhalers with formulations and patients are also provided. It is highlighted that the delicate manipulation of swirling flow is essential to maximize benefits. By emphasizing the role of swirling flow and its potential application, this review offers promising insights for advancing DPI technology and optimizing therapeutic outcomes in inhaled therapy.

Immunological properties of silica nanoparticles: a structure-activity relationship study

Silica nanoparticles are increasingly considered for drug delivery applications. These applications require an understanding of their biocompatibility, including their interactions with the immune system. However, systematic studies for silica nanoparticle immunological safety profiles are lacking. To fill this gap, we conducted an in vitro study investigating various aspects of silica nanoparticles' interactions with blood and immune cells. Four types of silica nanoparticles with variations in size and porosity were studied. These included nonporous Stöber silica nanoparticles with average diameters of approximately 50 and 100 nm (SNP50 and SNP100), mesoporous silica nanoparticles of approximately 100 nm (Meso100), and hollow mesoporous silica nanoparticles of approximately 100 nm (HMSNP100) in diameter, respectively. The hematological compatibility was assessed using hemolysis, complement activation, platelet aggregation, and plasma coagulation assays. The effects of nanoparticles on immune cell function were studied using in vitro phagocytosis, chemotaxis, natural killer cell cytotoxicity, leukocyte proliferation, human lymphocyte activation, colony-forming unit granulocyte-macrophage, and leukocyte procoagulant activity assays. The in vitro findings suggest that at high concentrations, corresponding to the in vivo human dose of 40 mg/kg, silica nanoparticles demonstrated an array of immunotoxic effects that depended on their physicochemical properties. However, all types of silica nanoparticles studied were not immunotoxic at concentrations corresponding to lower doses (≤ 8 mg/kg) comparable to that of nanocarriers in other nanomedicines currently used in the clinic. These findings are promising for using silica nanoparticles for the systemic delivery of bioactive and imaging agents.

Silica nanoparticles triggered epithelial ferroptosis via miR-21-5p/GCLM signaling to contribute to fibrogenesis in the lungs

The toxicity of silica nanoparticles (SiNPs) to lung is known. We previously demonstrated that exposure to SiNPs promoted pulmonary impairments, but the precise pathogenesis remains elucidated. Ferroptosis has now been identified as a unique form of oxidative cell death, but whether it participated in SiNPs-induced lung injury remains unclear. In this work, we established a rat model with sub-chronic inhalation exposure of SiNPs via intratracheal instillation, and conducted histopathological examination, iron detection, and ferroptosis-related lipid peroxidation and protein assays. Moreover, we evaluated the effect of SiNPs on epithelial ferroptosis, possible mechanisms using in vitro-cultured human bronchial epithelial cells (16HBE), and also assessed the ensuing impact on fibroblast activation for fibrogenesis. Consequently, fibrotic lesions occurred in the rat lungs, concomitantly by enhanced lipid peroxidation, iron overload, and ferroptosis. Consistently, the in vitro data showed SiNPs triggered oxidative stress and caused the accumulation of lipid peroxides, resulting in ferroptosis. Importantly, the mechanistic investigation revealed miR-21-5p as a key player in the epithelial ferroptotic process induced by SiNPs via targeting GCLM for GSH depletion. Of note, ferrostatin-1 could greatly suppress ferroptosis and alleviate epithelial injury and ensuing fibroblast activation by SiNPs. In conclusion, our findings first revealed SiNPs triggered epithelial ferroptosis through miR-21-5p/GCLM signaling and thereby promoted fibroblast activation for fibrotic lesions, and highlighted the therapeutic potential of inhibiting ferroptosis against lung impairments upon SiNPs exposure.

Targeting TRPs in autophagy regulation and human diseases

Transient receptor potential channels (TRPs) are widely recognized as a group of ion channels involved in various sensory perceptions, such as temperature, taste, pressure, and vision. While macroautophagy (hereafter referred to as autophagy) is primarily regulated by core machinery, the ion exchange mediated by TRPs between intracellular and extracellular compartments, as well as within organelles and the cytoplasm, plays a crucial role in autophagy regulation as an important signaling transduction mechanism. Moreover, certain TRPs can directly interact with autophagy regulatory proteins to participate in autophagy regulation. In this article, we provide an in-depth review of the current understanding of the regulatory mechanisms of autophagy, with a specific focus on TRPs. Furthermore, we highlight the potential prospects for drug development targeting TRPs in autophagy for the treatment of human diseases.

Advancements in Nanoporous Materials for Biomedical Imaging and Diagnostics

This review explores the latest advancements in nanoporous materials and their applications in biomedical imaging and diagnostics. Nanoporous materials possess unique structural features, including high surface area, tunable pore size, and versatile surface chemistry, making them highly promising platforms for a range of biomedical applications. This review begins by providing an overview of the various types of nanoporous materials, including mesoporous silica nanoparticles, metal-organic frameworks, carbon-based materials, and nanoporous gold. The synthesis method for each material, their current research trends, and prospects are discussed in detail. Furthermore, this review delves into the functionalization and surface modification techniques employed to tailor nanoporous materials for specific biomedical imaging applications. This section covers chemical functionalization, bioconjugation strategies, and surface coating and encapsulation methods. Additionally, this review examines the diverse biomedical imaging techniques enabled by nanoporous materials, such as fluorescence imaging, magnetic resonance imaging (MRI), computed tomography (CT) imaging, ultrasound imaging, and multimodal imaging. The mechanisms underlying these imaging techniques, their diagnostic applications, and their efficacy in clinical settings are thoroughly explored. Through an extensive analysis of recent research findings and emerging trends, this review underscores the transformative potential of nanoporous materials in advancing biomedical imaging and diagnostics. The integration of interdisciplinary approaches, innovative synthesis techniques, and functionalization strategies offers promising avenues for the development of next-generation imaging agents and diagnostic tools with enhanced sensitivity, specificity, and biocompatibility.

Silicon dioxide nanoparticles induce anxiety-like behavior in a size-specific manner via the microbiota-gut-brain axis

The impacts of silicon dioxide nanoparticles (SiO2-NPs) on human health have attracted increasing interest due to their widespread utilization in medicine and food additives. However, the size-dependent effects of SiO2-NPs on brain health remain sparse. Herein we investigated alterations in behavioral patterns, the gut microbiota, inflammation and oxidative stress of mice after a 12-week exposure to SiO2-NPs with either small size (NP-S) or large size (NP-L). A more pronounced deleterious effect of NP-S was found on anxiety-like behavior in mice relative to NP-L. We also found that SiO2-NPs exposure induced inflammation and oxidative stress in the colon, hippocampus and cortex of mice in a size-specific manner. Correlation network analysis revealed potential links between anxiety-like behavior and SiO2-NPs-induced shifts in the gut microbiota including Parvibacter, Faecalibaculum, Gordonibacter and Ileibacterium. Furthermore, anxiety-like behavior caused by SiO2-NPs exposure exhibited correlations with decreased levels of hippocampal IL-10 and cortex Nqo1 as well as increased levels of intestinal Acox1 and hippocampal TNF-α. Therefore, our findings suggest that exposure to SiO2-NPs promoted anxiety-like behavior through the mediation of interplay between the gut and the brain, and SiO2-NPs of smaller size may generate a more adverse effect on brain health.

All Roads Lead to Rome: Comparing Nanoparticle- and Small Molecule-Driven Cell Autophagy

Autophagy, vital for removing cellular waste, is triggered differently by small molecules and nanoparticles. Small molecules, like rapamycin, non-selectively activate autophagy by inhibiting the mTOR pathway, which is essential for cell regulation. This can clear damaged components but may cause cytotoxicity with prolonged use. Nanoparticles, however, induce autophagy, often causing oxidative stress, through broader cellular interactions and can lead to a targeted form known as "xenophagy." Their impact varies with their properties but can be harnessed therapeutically. In this review, the autophagy induced by nanoparticles is explored and small molecules across four dimensions: the mechanisms behind autophagy induction, the outcomes of such induction, the toxicological effects on cellular autophagy, and the therapeutic potential of employing autophagy triggered by nanoparticles or small molecules. Although small molecules and nanoparticles each induce autophagy through different pathways and lead to diverse effects, both represent invaluable tools in cell biology, nanomedicine, and drug discovery, offering unique insights and therapeutic opportunities.

Current Advances in Nanomaterials Affecting Functions and Morphology of Platelets

Nanomaterials have been extensively used in the biomedical field due to their unique physical and chemical properties. They promise wide applications in the diagnosis, prevention, and treatment of diseases. Nanodrugs are generally transported to target tissues or organs by coupling targeting molecules or enhanced permeability and retention effect (EPR) passively. As intravenous injection is the most common means of administration of nanomedicine, the transport process inevitably involves the interactions between nanoparticles (NPs) and blood cells. Platelets are known to not only play a critical role in normal coagulation by performing adhesion, aggregation, release, and contraction functions, but also be associated with pathological thrombosis, tumor metastasis, inflammation, and immune reactions, making it necessary to investigate the effects of NPs on platelet function during transport, particularly the way in which their physical and chemical properties determine their interaction with platelets and the underlying mechanisms by which they activate and induce platelet aggregation. However, such data are lacking. This review is intended to summarize the effects of NPs on platelet activation, aggregation, release, and apoptosis, as well as their effects on membrane proteins and morphology in order to shed light on such key issues as how to reduce their adverse reactions in the blood system, which should be taken into consideration in NP engineering.

Research Progress on Micro(nano)plastic-Induced Programmed Cell Death Associated with Disease Risks

Due to their robust migration capabilities, slow degradation, and propensity for adsorbing environmental pollutants, micro(nano)plastics (MNPs) are pervasive across diverse ecosystems. They infiltrate various organisms within different food chains through multiple pathways including inhalation and dermal contact, and pose a significant environmental challenge in the 21st century. Research indicates that MNPs pose health threats to a broad range of organisms, including humans. Currently, extensive detection data and studies using experimental animals and in vitro cell culture indicate that MNPs can trigger various forms of programmed cell death (PCD) and can induce various diseases. This review provides a comprehensive and systematic analysis of different MNP-induced PCD processes, including pyroptosis, ferroptosis, autophagy, necroptosis, and apoptosis, based on recent research findings and focuses on elucidating the links between PCD and diseases. Additionally, targeted therapeutic interventions for these diseases are described. This review provides original insights into the opportunities and challenges posed by current research findings. This review evaluates ways to mitigate various diseases resulting from cell death patterns. Moreover, this paper enhances the understanding of the biohazards associated with MNPs by providing a systematic reference for subsequent toxicological research and health risk mitigation efforts.

Realistic Nanoplastics Induced Pulmonary Damage via the Crosstalk of Ferritinophagy and Mitochondrial Dysfunction

The smaller size fraction of plastics may be more substantially existing and detrimental than larger-sized particles. However, reports on nanoplastics (NPs), especially their airborne occurrences and potential health hazards to the respiratory system, are scarce. Previous studies limit the understanding of their real respiratory effects, since sphere-type polystyrene (PS) nanoparticles differ from NPs occurring in nature with respect to their physicochemical properties. Here, we employ a mechanical breakdown method, producing NPs directly from bulk plastic, preserving NP properties in nature. We report that among four relatively high abundance NP materials PS, polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polyethylene (PE) with a size of 100 nm, PVC induced slightly more severe lung toxicity profiles compared to the other plastics. The lung cytotoxicity of NPs is higher than that of commercial PS NPs and comparable to natural particles silicon dioxide (SiO2) and anatase titanium dioxide (TiO2). Mechanistically, BH3-interacting domain death agonist (Bid) transactivation-mediated mitochondrial dysfunction and nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy or ferroptosis are likely common mechanisms of NPs regardless of their chemical composition. This study provides relatively comprehensive data for evaluating the risk of atmospheric NPs to lung health.

ROS-mediated NRF2/p-ERK1/2 signaling-involved mitophagy contributes to macrophages activation induced by CdTe quantum dots

Cadmium telluride (CdTe) quantum dots (QDs) have garnered significant attention for tumor imaging due to their exceptional properties. However, there remains a need for further investigation into their potential toxicity mechanisms and corresponding enhancements. Herein, CdTe QDs were observed to accumulate in mouse liver, leading to a remarkable overproduction of IL-1β and IL-6. Additionally, there was evidence of macrophage infiltration and activation following exposure to 12.5 μmol/kg body weight of QDs. To elucidate the underlying mechanism of macrophage activation, CdTe QDs functionalized with 3-mercaptopropionic acid (MPA) were utilized. In vitro experiments revealed that 1.0 μM MPA-CdTe QDs activated PINK1-dependent mitophagy in RAW264.7 macrophages. Critically, the autophagic flux remained unimpeded, as demonstrated by the absence of p62 accumulation, LC3 turnover assay results, and successful fusion of autophagosomes with lysosomes. Mechanically, QDs increased reactive oxygen species (ROS) and mitoROS by damaging both mitochondria and lysosomes. ROS, in turn, inhibited NRF2, resulting in the phosphorylation of ERK1/2 and subsequent activation of mitophagy. Notably, 1.0 μM QDs disrupted lysosomes but autophagic flux was not impaired. Eventually, the involvement of the ROS-NRF2-ERK1/2 pathway-mediated mitophagy in the increase of IL-1β and IL-6 in macrophages was confirmed using Trolox, MitoTEMPO, ML385, specific siRNAs, and lentivirus-based interventions. This study innovatively revealed the pro-inflammatory rather than anti-inflammatory role of mitophagy in nanotoxicology, shedding new light on the mechanisms of mitochondrial disorders induced by QDs and identifying several molecular targets to comprehend the toxicological mechanisms of CdTe QDs.

Comprehensive pulmonary metabolic responses to silica nanoparticles exposure in Fisher 344 rats

Silica nanoparticles (SiNPs) could induce adverse pulmonary effects, but the mechanism was not clear enough. Metabolomics is a sensitive and high-throughput approach that could investigate the intrinsic causes of adverse health effects caused by SiNPs. The current investigation represented the first in vivo metabolomics study examining the chronic pulmonary toxicity of SiNPs at a low dosage, mimicking real human exposure situation. The recovery process after the cessation of exposure was also taken into consideration. Fisher 344 rats were treated with either saline or SiNPs for 6 months. Half of the animals in each group received an additional six-month period for recovery. The findings indicated that chronic low-level exposure to SiNPs resulted in notable alterations in pulmonary metabolism of amino acids, lipids, carbohydrates, and nucleotides. SiNPs exerted an impact on various metabolites and metabolic pathways which are linked to oxidative stress, inflammation and tumorigenesis. These included but were not limited to L-carnitine, spermidine, taurine, xanthine, and glutathione metabolism. The metabolic alterations caused by SiNPs exhibited a degree of reversibility. However, the interference of SiNPs on two metabolic pathways related to tumorigenesis was observed to persist after a recovery period. The two metabolic pathways are glycerophospholipid metabolism as well as phenylalanine, tyrosine and tryptophan biosynthesis. This study elucidated the metabolic alterations induced by chronic low-level exposure to SiNPs and presented novel evidence of the chronic pulmonary toxicity and carcinogenicity of SiNPs, from a metabolomic perspective.

TRPM2-dependent autophagy inhibition exacerbates oxidative stress-induced CXCL16 secretion by keratinocytes in vitiligo

Vitiligo is a depigmented skin disease due to the destruction of melanocytes. Under oxidative stress, keratinocyte-derived chemokine C-X-C motif ligand 16 (CXCL16) plays a critical role in recruiting CD8+ T cells, which kill melanocytes. Autophagy serves as a protective cell survival mechanism and impairment of autophagy has been linked to increased secretion of the proinflammatory cytokines. However, the role of autophagy in the secretion of CXCL16 under oxidative stress has not been investigated. Herein, we initially found that autophagy was suppressed in both keratinocytes of vitiligo lesions and keratinocytes exposed to oxidative stress in vitro. Autophagy inhibition also promoted CXCL16 secretion. Furthermore, upregulated transient receptor potential cation channel subfamily M member 2 (TRPM2) functioned as an upstream oxidative stress sensor to inhibit autophagy. Moreover, TRPM2-mediated Ca2+ influx activated calpain to shear autophagy related 5 (Atg5) and Atg12-Atg5 conjugate formation was blocked to inhibit autophagy under oxidative stress. More importantly, Atg5 downregulation enhanced the binding of interferon regulatory factor 3 (IRF3) to the CXCL16 promoter region by activating Tank-binding kinase 1 (TBK1), thus promoting CXCL16 secretion. These findings suggested that TRPM2-restrained autophagy promotes CXCL16 secretion via the Atg5-TBK1-IRF3 signaling pathway under oxidative stress. Inhibition of TRPM2 may serve as a potential target for the treatment of vitiligo. © 2024 The Pathological Society of Great Britain and Ireland.

Silica nanoparticles in medicine: overcoming pathologies through advanced drug delivery, diagnostics, and therapeutic strategies

Over the last decades, silica nanoparticles (SiNPs) have been studied for their applications in biomedicine as an alternative used for conventional diagnostics and treatments. Since their properties can be modified and adjusted for the desired use, they have many different potential applications in medicine: they can be used in diagnosis because of their ability to be loaded with dyes and their increased selectivity and sensitivity, which can improve the quality of the diagnostic process. SiNPs can be functionalized by targeting ligands or molecules to detect certain cellular processes or biomarkers with better precision. Targeted delivery is another fundamental use of SiNPs. They could be used as drug delivery systems (DDS) since their structure allows the loading of therapeutic agents or other compounds, and studies have demonstrated their biocompatibility. When SiNPs are used as DDS, the drug's toxicity and the off-target effects are reduced significantly, and they can be used to treat conditions like cancer and neurological diseases and even aid in regenerative processes, such as wound healing or bone repair. However, safety concerns must be considered before SiNPs can be used extensively in clinical practice because NPs can cause toxicity in certain conditions and accumulate at undesired locations. Therefore, an overview of the potential applications that SiNPs could have in medicine, as well as their safety concerns, will be covered in this review paper.

Multi-omics analysis of lung tissue metabolome and proteome reveals the therapeutic effect of Shegan Mahuang Decoction against asthma in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Shegan Mahuang Decoction (SMD) is a classic traditional Chinese medicine (TCM) formula for asthma treatment, but the anti-asthma mechanism of SMD is still not fully studied.

AIMS OF THE STUDY

In this study, we established an ovalbumin (OVA)-induced asthma rat model and treated it with SMD to observe its anti-asthma effect and explore the related mechanism.

MATERIALS AND METHODS

We evaluated the anti-inflammatory effect of SMD via testing the levels of immunoglobulin E (IgE), C-reactive protein (CRP), interleukin-4 (IL-4), interleukin-6 (IL-6) in serum and performing the hematoxylin-eosin (H&E) staining of lung tissue slices. We analyzed the variations of metabolites and proteins in the lung tissue of different groups using liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics and TMT-based proteomics approaches. The metabolic biomarkers and differentially expressed proteins (DEPs) were picked, and the related signal transduction pathways were also investigated. In addition, the key proteins on the signaling pathway were validated through western blotting (WB) experiment to reveal the anti-asthma mechanism of SMD.

RESULTS

The results showed that the SMD could significantly reduce the serum levels of IgE, CRP, IL-4, and IL-6 and attenuate the OVA-induced pathological changes in lung tissue. A total of 34 metabolic biomarkers and 84 DEPs were screened from rat lung tissue, which were mainly associated with lipid metabolism, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, the excessive production of reactive oxygen species (ROS), and lysosome pathway. Besides, SMD could inhibit the myeloid differentiation factor 88 (MyD88)/inhibitor of kappa B kinase (IKK)/nuclear factor-kappa B (NF-κB) signaling pathway to exhibit anti-inflammatory activities.

CONCLUSIONS

SMD exhibited a therapeutic effect on asthma, which possibly be exerted by inhibiting the MyD88/IKK/NF-κB signaling pathway.

State of the Art of Silica Nanoparticles: An Overview on Biodistribution and Preclinical Toxicity Studies

Over the past few years, nanoparticles have drawn particular attention in designing and developing drug delivery systems due to their distinctive advantages like improved pharmacokinetics, reduced toxicity, and specificity. Along with other successful nanosystems, silica nanoparticles (SNPs) have shown promising effects for therapeutic and diagnostic purposes. These nanoparticles are of great significance owing to their modifiable surface with various ligands, tunable particle size, and large surface area. The rate and extent of degradation and clearance of SNPs depend on factors such as size, shape, porosity, and surface modification, which directly lead to varying toxic mechanisms. Despite SNPs' enormous potential for clinical and pharmaceutical applications, safety concerns have hindered their translation into the clinic. This review discusses the biodistribution, toxicity, and clearance of SNPs and the formulation-related factors that ultimately influence clinical efficacy and safety for treatment. A holistic view of SNP safety will be beneficial for developing an enabling SNP-based drug product.

Advanced oxidation protein products attenuate the autophagy-lysosome pathway in ovarian granulosa cells by modulating the ROS-dependent mTOR-TFEB pathway

Oxidative stress dysfunction has recently been found to be involved in the pathogenesis of premature ovarian insufficiency (POI). Previously, we found that advanced oxidation protein products (AOPPs) in plasma were elevated in women with POI and had an adverse effect on granulosa cell proliferation. However, the mechanism underlying the effects of AOPPs on autophagy-lysosome pathway regulation in granulosa cells remains unclear. In this study, the effect of AOPPs on autophagy and lysosomal biogenesis and the underlying mechanisms were explored by a series of in vitro experiments in KGN and COV434 cell lines. AOPP-treated rat models were employed to determine the negative effect of AOPPs on the autophagy-lysosome systems in vivo. We found that increased AOPP levels activated the mammalian target of rapamycin (mTOR) pathway, and inhibited the autophagic response and lysosomal biogenesis in KGN and COV434 cells. Furthermore, scavenging of reactive oxygen species (ROS) with N-acetylcysteine and blockade of the mTOR pathway with rapamycin or via starvation alleviated the AOPP-induced inhibitory effects on autophagy and lysosomal biogenesis, suggesting that these effects of AOPPs are ROS-mTOR dependent. The protein expression and nuclear translocation of transcription factor EB (TFEB), the key regulator of lysosomal and autophagic function, were also impaired by the AOPP-activated ROS-mTOR pathway. In addition, TFEB overexpression attenuated the AOPP-induced impairment of autophagic flux and lysosomal biogenesis in KGN and COV434 cells. Chronic AOPP stimulation in vivo also impaired autophagy and lysosomal biogenesis in granulosa cells of rat ovaries. The results highlight that AOPPs lead to impairment of autophagic flux and lysosomal biogenesis via ROS-mTOR-TFEB signaling in granulosa cells and participate in the pathogenesis of POI.

Advances in the study of silica nanoparticles in lung diseases

Silicon dioxide nanoparticles (SiNPs) are one of the major forms of silicon dioxide and are composed of the most-abundant compounds on earth. Based on their excellent properties, SiNPs are widely used in food production, synthetic processes, medical diagnostics, drug delivery, and other fields. The mass production and wide application of SiNPs increases the risk of human exposure to SiNPs. In the workplace and environment, SiNPs mainly enter the human body through the respiratory tract and reach the lungs; therefore, the lungs are the most important and most toxicologically affected target organ of SiNPs. An increasing number of studies have shown that SiNP exposure can cause severe lung toxicity. However, studies on the toxicity of SiNPs in ex vivo and in vivo settings are still in the exploratory phase. The molecular mechanisms underlying the lung toxicity of SiNPs are varied and not yet fully understood. As a result, this review summarizes the possible mechanisms of SiNP-induced lung toxicity, such as oxidative stress, endoplasmic reticulum stress, mitochondrial damage, and cell death. Moreover, this study provides a summary of the progression of diseases caused by SiNPs, thereby establishing a theoretical basis for future studies on the mechanisms of SiNP-induced lung toxicity.

Silica Nanoparticle Exposure Implicates β-Amyloid (1-42) Inbound and the Accelerating Alzheimer's Disease Progression in Mice Overexpressing Mutated Forms of Human Amyloid Precursor Protein and Presenilin 1 Genes

The increasing nanoparticle (NP) applications in the biomedical field have become an emerging concern regarding human health. NP exposure may play a role in the accelerating Alzheimer's disease (AD) progression; however, the etiology of this disorder is complex and remains largely unclear. Here, we identified that intravenous injection of silica NPs (SiNPs) caused the blood-brain barrier breakdown via downregulating tight junction-related gene expressions. Meanwhile, SiNPs upregulate the transport receptor for advanced glycation end products (RAGE) that govern the β-amyloid (Aβ) influx to the brain; however, low-density lipoprotein receptor-related protein 1 (LRP1) that controls the efflux of Aβ from the brain was not affected. Consequently, an increase in Aβ burden in the brain of SiNP-challenged APP/PS1 mice was found. Intriguingly, plasma apolipoprotein E (ApoE) adsorbed on the surface of SiNPs partially relieves this effect. Using ApoE knockout (ApoE-/-) mice, we confirmed that SiNPs covered with serum without ApoE showed further elevated AD symptoms. Together, this study offered a compilation of data to support the potential risk factors of NP exposure and AD pathology.

Prolonged cough and dyspnea following a single episode of intense silica exposure

Long term exposure to silica at worksites can cause silicosis. This typically has two radiographic forms, simple silicosis and complicated or conglomerate silicosis. Patients with acute silicosis have rapid progression of disease with fulminant respiratory failure over months rather than years. The patient described in this case report had a one-time 4 to 5-h exposure to silica and sand dust at work when his mask malfunctioned. He developed cough and shortness of breath. During his initial clinic visit he had significant cough. His chest examination was clear without crackles or wheezes. His pulmonary function tests were within normal limits. His chest x-ray was clear. Both symptoms, especially the cough, persisted over the next 6+ months even after treatment with oral corticosteroids and inhaled corticosteroids and long-acting beta agonists. Consequently, this patient developed severe cough following a one-time exposure to silica particulates. Laboratory studies have demonstrated that silica exposure can cause reactive oxygen species which potentially could have activated transient receptor potential vanilloid 1 channels in the afferent sensory nerves in his bronchial epithelium. This could cause sustained cough for more than 6 months. His symptoms improved but did not resolve with corticosteroid treatment. Therefore, this case demonstrates that acute silica exposure can cause sustained airway symptoms in healthy workers.

Intratracheal administration of cross-linked water-soluble acrylic acid polymer is associated with inducible bronchi-related lymphoid tissue formation and allergic inflammation

In a Japanese chemical factory, lung diseases such as pneumoconiosis have been reported among workers handling cross-linked water-soluble acrylic acid polymers (CWAAP). Our previous study reported that a single intratracheal administration of CWAAP induces acute inflammation and fibrosis. In this study, we investigated the effects of multiple intratracheal administrations of CWAAP on inflammatory responses and pulmonary fibrosis along with inducible bronchus-associated lymphoid tissues (iBALT) formation, which is involved in allergic inflammation. Male F344 rats (190-200 g) received single or multiple intratracheal administrations of phosphate-buffered saline (PBS) or CWAAP. To assess inflammatory responses and pulmonary fibrosis, immunohistochemical and histological staining was performed. CD68, CD163, CD169, TGF-β, and collagen I positive cells/areas in the lungs of the CWAAP-group rats were significantly increased than those in the PBS group. Furthermore, the number of iBALT structures, CD4 + T cells, along with CD19, PAX5, IL-4, GATA-3, T-bet, and IgE-positive cells in the terminal bronchioles and blood vessels of the lungs were significantly increased in the CWAAP group. Moreover, pulmonary fibrosis, iBALT formation, and levels of specific IgG were significantly increased in rats who received multiple intratracheal administrations of CWAAP compared to those with single intratracheal administration. Multiple intratracheal administrations of CWAAP potentiated the classical fibrotic pathway (M2 macrophage-TGF-β-collagen I) more potently than single intratracheal administration. Furthermore, it was possible that iBALT was formed around terminal bronchioles and blood vessels and the number of immune cells was increased, resulting in enhanced allergic inflammation and pulmonary fibrosis.

Enhanced Sensitivity of A549 Cells to Doxorubicin with WS2 and WSe2 Nanosheets via the Induction of Autophagy

The excellent physicochemical properties of two-dimensional transition-metal dichalcogenides (2D TMDCs) such as WS2 and WSe2 provide potential benefits for biomedical applications, such as drug delivery, photothermal therapy, and bioimaging. WS2 and WSe2 have recently been used as chemosensitizers; however, the detailed molecular basis underlying WS2- and WSe2-induced sensitization remains elusive. Our recent findings showed that 2D TMDCs with different thicknesses and different element compositions induced autophagy in normal human bronchial epithelial cells and mouse alveolar macrophages at sublethal concentrations. Here, we explored the mechanism by which WS2 and WSe2 act as sensitizers to increase lung cancer cell susceptibility to chemotherapeutic agents. The results showed that WS2 and WSe2 enhanced autophagy flux in A549 lung cancer cells at sublethal concentrations without causing significant cell death. Through the autophagy-specific RT2 Profiler PCR Array, we identified the genes significantly affected by WS2 and WSe2 treatment. Furthermore, the key genes that play central roles in regulating autophagy were identified by constructing a molecular interaction network. A mechanism investigation uncovered that WS2 and WSe2 activated autophagy-related signaling pathways by interacting with different cell surface proteins or cytoplasmic proteins. By utilizing this mechanism, the efficacy of the chemotherapeutic agent doxorubicin was enhanced by WS2 and WSe2 pre-treatment in A549 lung cancer cells. This study revealed a feature of WS2 and WSe2 in cancer therapy, in which they eliminate the resistance of A549 lung cancer cells against doxorubicin, at least partially, by inducing autophagy.

Crucial physicochemical factors mediating mitochondrial toxicity of nanoparticles at noncytotoxic concentration

Nanomaterials have been extensively applied in multiple industries, among which silver nanoparticles (AgNPs), silicon dioxide nanoparticles (SiNPs), and gold nanoparticles (AuNPs) have become representative of widely consumed NPs. Limited knowledge is available regarding the subcellular responses of NPs with different physicochemical properties, i.e. material type and size, under the noncytotoxic concentrations. Macrophages are important sensitive cells exposed to NPs, and mitochondria are sensitive organelles that respond at the subcellular level. Herein, we found that sublethal concentrations of AgNPs and SiNPs, not AuNPs, decreased the mitochondrial membrane potential (MMP) and tubular mitochondria, and further resulted in an increase of ROS level and a decrease of ATP generation. AgNPs and SiNPs can also disturb mitochondrial dynamics manifested as increasing Mfn2 expression and decreasing Drp1 expression. Further assessments for mitochondrial function showed that AgNPs and SiNPs exposure led to a decrease in the gene expressions related to complex I (Ndufa8 and Ndufs2), complex III (Uqcrc2 and Uqcrfs1), complex IV (Cox6b1), and activity of complex I, suggesting their potential roles in impairing cellular respiration. In terms of the effects of NPs with different sizes, stronger toxicity was observed in smaller-sized nanoparticles. Among the above mitochondrial changes, we identified that ROS, ATP, MMP, tubular mitochondria, and expression of Drp1 were relatively sensitive indicators in subcellular response to NPs. With the above sensitive indicators, the comparison of heterogeneity between material type and size of the NPs showed that material type occupied a main influence on subcellular mitochondrial effects. Our finding provided important data on the potential subcellular risks of NPs, and indicated the vital role of material type for a better understanding of the nanomaterial biological safety.

Silica nanoparticles induce ferroptosis of HUVECs by triggering NCOA4-mediated ferritinophagy

Silica nanoparticles (SiNPs) have been widely used in electronics, chemistry, and biomedicine. Human exposure to SiNPs and possible health effects have attracted much attention. The potential cardiovascular toxicity of SiNPs and their related mechanisms are still unclear. Therefore, in this study, we investigated the toxic effects of SiNPs on human umbilical vein endothelial cells (HUVECs). We found that SiNPs could induce HUVECs ferroptosis. The results showed that the level of intracellular divalent iron and lipid peroxidation increased, and mitochondrial cristae decreased. In addition, the pretreatment of the iron chelator deferoxamine mesylate (DFO) could alleviate the ferroptosis of cells. Interestingly, pretreatment of 3-methyladenine (3-MA), an autophagy/PI3K inhibitor could partially inhibit autophagy and reduce ferroptosis, which indicated that autophagy played an important role in cell ferroptosis. Additionally, after knocking down nuclear receptor coactivator 4 (NCOA4), Ferritin Heavy Chain 1 (FTH1) expression was up-regulated, and the levels of divalent iron and lipid peroxidation decreased, which suggested that NCOA4 mediated the ferroptosis of HUVECs induced by SiNPs. In conclusion, this study shows that SiNPs can induce cardiovascular toxicity in which there is ferroptosis. NCOA4-mediated ferritinophagy and resultant ferroptosis by SiNPs may play an important role. This study provides a new theoretical strategy for the treatment and prevention of cardiovascular diseases in the future.

ALKBH5 mediates silica particles-induced pulmonary inflammation through increased m6A modification of Slamf7 and autophagy dysfunction

Silica particles are commonly encountered in natural and industrial activities. Long-term environmental exposure to silica can result in silicosis, which is characterized by chronic inflammation and abnormal tissue repair in lung. To uncover the role of m6A modification in silica-induced pulmonary inflammation, we conducted this study using established mouse and macrophage models. In this study, the aerodynamic diameter of silica particles was approximately 1-2 µm. We demonstrated that silica exposure in mice caused pulmonary inflammation and increased global m6A modification levels, the downregulation of alkB homolog 5 (ALKBH5) might contribute to this alteration. Besides, we found that F4/80, a macrophage-specific biomarker, was co-expressed with ALKBH5 through dual immunofluorescent staining. In vitro studies using MeRIP assays suggested that Slamf7 was a target gene regulated by m6A modification, and specific inhibition of ALKBH5 increased Slamf7 expression. Mechanistically, ALKBH5 promoted m6A modification of Slamf7, which decreased Slamf7 mRNA stability in an m6A-dependent manner, ultimately regulating Slamf7 expression. In addition, silica exposure activated PI3K/AKT and induced macrophage autophagy. Inhibition of Slamf7 promoted autophagy, reduced the secretion of pro-inflammatory cytokines, and improved silica-induced pulmonary inflammation. In summary, ALKBH5 can regulate silica-induced pulmonary inflammation by modulating Slamf7 m6A modification and affecting the function of macrophage autophagy.

Bioinformatics-driven discovery of silica nanoparticles induces apoptosis and renal damage via the unfolded protein response in NRK-52E cells and rat kidney

Silica nanoparticles (SiNPs) are nanomaterials with widespread applications in drug delivery and disease diagnosis. Despite their utility, SiNPs can cause chronic kidney disease, hindering their clinical translation. The molecular mechanisms underlying SiNP-induced renal toxicity are complex and require further investigation. To address this challenge, we employed bioinformatics tools to predict the potential mechanisms underlying renal damage caused by SiNPs. We identified 1627 upregulated differentially expressed genes (DEGs) and 1334 downregulated DEGs. Functional enrichment analysis and protein-protein interaction network revealed that SiNP-induced renal damage is associated with apoptosis. Subsequently, we verified that SiNPs induced apoptosis in an in vitro model of NRK-52E cells via the unfolded protein response (UPR) in a dose-dependent manner. Furthermore, in an in vivo rat model, high-dose SiNP administration via tracheal drip caused hyalinization of the renal tubules, renal interstitial lymphocytic infiltration, and collagen fiber accumulation. Concurrently, we observed an increase in UPR-related protein levels at the onset of renal damage. Thus, our study confirmed that SiNPs induce apoptosis and renal damage through the UPR, adding to the theoretical understanding of SiNP-related kidney damage and offering a potential target for preventing and treating kidney injuries in SiNP clinical applications.

Adverse effects of exposure to fine particles and ultrafine particles in the environment on different organs of organisms

Particulate pollution is a global risk factor that seriously threatens human health. Fine particles (FPs) and ultrafine particles (UFPs) have small particle diameters and large specific surface areas, which can easily adsorb metals, microorganisms and other pollutants. FPs and UFPs can enter the human body in multiple ways and can be easily and quickly absorbed by the cells, tissues and organs. In the body, the particles can induce oxidative stress, inflammatory response and apoptosis, furthermore causing great adverse effects. Epidemiological studies mainly take the population as the research object to study the distribution of diseases and health conditions in a specific population and to focus on the identification of influencing factors. However, the mechanism by which a substance harms the health of organisms is mainly demonstrated through toxicological studies. Combining epidemiological studies with toxicological studies will provide a more systematic and comprehensive understanding of the impact of PM on the health of organisms. In this review, the sources, compositions, and morphologies of FPs and UFPs are briefly introduced in the first part. The effects and action mechanisms of exposure to FPs and UFPs on the heart, lungs, brain, liver, spleen, kidneys, pancreas, gastrointestinal tract, joints and reproductive system are systematically summarized. In addition, challenges are further pointed out at the end of the paper. This work provides useful theoretical guidance and a strong experimental foundation for investigating and preventing the adverse effects of FPs and UFPs on human health.

Autophagy-mediated nanomaterials for tumor therapy

Autophagy is a lysosomal self-degradation pathway that plays an important protective role in maintaining intracellular environment. Deregulation of autophagy is related to several diseases, including cancer, infection, neurodegeneration, aging, and heart disease. In this review, we will summarize recent advances in autophagy-mediated nanomaterials for tumor therapy. Firstly, the autophagy signaling pathway for tumor therapy will be reviewed, including oxidative stress, mammalian target of rapamycin (mTOR) signaling and autophagy-associated genes pathway. Based on that, many autophagy-mediated nanomaterials have been developed and applied in tumor therapy. According to the different structure of nanomaterials, we will review and evaluate these autophagy-mediated nanomaterials' therapeutic efficacy and potential clinical application.

Prospects and hazards of silica nanoparticles: Biological impacts and implicated mechanisms

With the thrive of nanotechnology, silica nanoparticles (SiNPs) have been extensively adopted in the agriculture, food, cosmetic, and even biomedical industries. Due to the mass production and use, SiNPs inevitably entered the environment, resulting in ecological toxicity and even posing a threat to human health. Although considerable investigations have been conducted to assess the toxicity of SiNPs, the correlation between SiNPs exposure and consequent health risks remains ambiguous. Since the biological impacts of SiNPs can differ from their design and application, the toxicity assessment for SiNPs may be extremely difficult. This review discussed the application of SiNPs in different fields, especially their biomedical use, and documented their potential release pathways into the environment. Meanwhile, the current process of assessing SiNPs-related toxicity on various model organisms and cell lines was also detailed, thus estimating the health threats posed by SiNPs exposure. Finally, the potential toxic mechanisms of SiNPs were also elaborated based on results obtained from both in vivo and in vitro trials. This review generally summarizes the biological effects of SiNPs, which will build up a comprehensive perspective of the application and toxicity of SiNPs.

Unmasking the complex roles of hypocalcemia in cancer, COVID-19, and sepsis: Engineered nanodelivery and diagnosis

Calcium (Ca2+) homeostasis is essential for maintaining physiological processes in the body. Disruptions in Ca2+ signaling can lead to various pathological conditions including inflammation, fibrosis, impaired immune function, and accelerated senescence. Hypocalcemia, a common symptom in diseases such as acute respiratory distress syndrome (ARDS), cancer, septic shock, and COVID-19, can have both potential protective and detrimental effects. This article explores the multifaceted role of Ca2+ dysregulation in inflammation, fibrosis, impaired immune function, and accelerated senescence, contributing to disease severity. Targeting Ca2+ signaling pathways may provide opportunities to develop novel therapeutics for age-related diseases and combat viral infections. However, the role of Ca2+ in viral infections is complex, and evidence suggests that hypocalcemia may have a protective effect against certain viruses, while changes in Ca2+ homeostasis can influence susceptibility to viral infections. The effectiveness and safety of Ca2+ supplements in COVID-19 patients remain a subject of ongoing research and debate. Further investigations are needed to understand the intricate interplay between Ca2+ signaling and disease pathogenesis.

Clinical Efficacy of Ulinastatin Combined with Azithromycin in the Treatment of Severe Pneumonia in Children and the Effects on Inflammatory Cytokines and Oxidative Stress: A Retrospective Cohort Study

Purpose

This retrospective cohort study aimed to evaluate the clinical efficacy of ulinastatin (UTI) and azithromycin (AZM) combination therapy in treating severe pneumonia in children and its impact on inflammatory cytokines and oxidative stress.

Patients and Methods

This retrospective cohort study was conducted from January 1, 2019, to January 1, 2021, involving pediatric patients diagnosed with severe mycoplasma pneumonia (SMPP). The pediatric patients were divided into two groups: those receiving UTI and AZM combination therapy (treatment group) and those receiving azithromycin alone (control group). We compared the two groups regarding clinical data, disease outcomes, inflammatory cytokines, and oxidative stress levels.

Results

Baseline characteristics did not significantly differ between the two groups. UTI, in combination with AZM, significantly improved blood oxygen levels, inflammatory infection markers, and relevant clinical symptoms in patients with SMPP on the 3rd day of treatment. Additionally, it significantly reduced the levels of inflammatory cytokines TNF-a, IL-6, IL-1β, and IL-10, as well as oxidative stress markers GSH and SOD.

Conclusion

Combining UTI and AZM can rapidly alleviate clinical symptoms and effectively control the progression of patients with SMPP. Therefore, this treatment approach deserves consideration for clinical promotion and utilization.

Disturbing cytoskeleton by engineered nanomaterials for enhanced cancer therapeutics

Cytoskeleton plays a significant role in the shape change, migration, movement, adhesion, cytokinesis, and phagocytosis of tumor cells. In clinical practice, some anti-cancer drugs achieve cytoskeletal therapeutic effects by acting on different cytoskeletal protein components. However, in the absence of cell-specific targeting, unnecessary cytoskeletal recombination in organisms would be disastrous, which would also bring about severe side effects during anticancer process. Nanomedicine have been proven to be superior to some small molecule drugs in cancer treatment due to better stability and targeting, and lower side effects. Therefore, this review summarized the recent developments of various nanomaterials disturbing cytoskeleton for enhanced cancer therapeutics, including carbon, noble metals, metal oxides, black phosphorus, calcium, silicon, polymers, peptides, and metal-organic frameworks, etc. A comprehensive analysis of the characteristics of cytoskeleton therapy as well as the future prospects and challenges towards clinical application were also discussed. We aim to drive on this emerging topic through refreshing perspectives based on our own work and what we have also learnt from others. This review will help researchers quickly understand relevant cytoskeletal therapeutic information to further advance the development of cancer nanomedicine.

Autophagy regulation by inorganic, organic, and organic/inorganic hybrid nanoparticles: Organelle damage, regulation factors, and potential pathways

The rapid development of nanotechnology requires a more thorough understanding of the potential health effects caused by nanoparticles (NPs). As a programmed cell death, autophagy is one of the biological effects induced by NPs, which maintain intracellular homeostasis by degrading damaged organelles and removing aggregates of defective proteins through lysosomes. Currently, autophagy has been shown to be associated with the development of several diseases. A significant number of research have demonstrated that most NPs can regulate autophagy, and their regulation of autophagy is divided into induction and blockade. Studying the autophagy regulation by NPs will facilitate a more comprehensive understanding of the toxicity of NPs. In this review, we will illustrate the effects of different types of NPs on autophagy, including inorganic NPs, organic NPs, and organic/inorganic hybrid NPs. The potential mechanisms by which NPs regulate autophagy are highlighted, including organelle damage, oxidative stress, inducible factors, and multiple signaling pathways. In addition, we list the factors influencing NPs-regulated autophagy. This review may provide basic information for the safety assessment of NPs.

Trpm2 deficiency in microglia attenuates neuroinflammation during epileptogenesis by upregulating autophagy via the AMPK/mTOR pathway

Epilepsy is one of the most common neurological disorders. Neuroinflammation involving the activation of microglia and astrocytes constitutes an important and common mechanism in epileptogenesis. Transient receptor potential melastatin 2 (TRPM2) is a calcium-permeable, non-selective cation channel that plays pathological roles in various inflammation-related diseases. Our previous study demonstrated that Trpm2 knockout exhibits therapeutic effects on pilocarpine-induced glial activation and neuroinflammation. However, whether TRPM2 in microglia and astrocytes plays a common pathogenic role in this process and the underlying molecular mechanisms remained undetermined. Here, we demonstrate a previously unknown role for microglial TRPM2 in epileptogenesis. Trpm2 knockout in microglia attenuated kainic acid (KA)-induced glial activation, inflammatory cytokines production and hippocampal paroxysmal discharges, whereas Trpm2 knockout in astrocytes exhibited no significant effects. Furthermore, we discovered that these therapeutic effects were mediated by upregulated autophagy via the adenosine monophosphate activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway in microglia. Thus, our findings highlight an important deleterious role of microglial TRPM2 in temporal lobe epilepsy.

Autophagy inhibitors for cancer therapy: Small molecules and nanomedicines

Autophagy is a conserved process in which the cytosolic materials are degraded and eventually recycled for cellular metabolism to maintain homeostasis. The dichotomous role of autophagy in pathogenesis is complicated. Accumulating reports have suggested that cytoprotective autophagy is responsible for tumor growth and progression. Autophagy inhibitors, such as chloroquine (CQ) and hydroxychloroquine (HCQ), are promising for treating malignancies or overcoming drug resistance in chemotherapy. With the rapid development of nanotechnology, nanomaterials also show autophagy-inhibitory effects or are reported as the carriers delivering autophagy inhibitors. In this review, we summarize the small-molecule compounds and nanomaterials inhibiting autophagic flux as well as the mechanisms involved. The nanocarrier-based drug delivery systems for autophagy inhibitors and their distinct advantages are also described. The progress of autophagy inhibitors for clinical applications is finally introduced, and their future perspectives are discussed.

Interplay of Oxidative Stress, Inflammation, and Autophagy in RAW 264.7 Murine Macrophage Cell Line Challenged with Si/SiO2 Quantum Dots

Quantum dots (QDs) with photostable fluorescence are recommended for imaging applications; however, their effect on living cells is incompletely understood. We aimed to elucidate the RAW 264.7 murine macrophage cell line's response to the Si/SiO₂ QDs challenge. Cells were exposed to 5 and 15 μg/mL Si/SiO₂ QDs for 6 h, 12 h, and 24 h. Cell metabolic activity and viability were assessed by MTT, live/dead, and dye-exclusion assays. Oxidative stress and membrane integrity were assessed by anion superoxide, malondialdehyde, and lactate dehydrogenase activity evaluations. Antioxidative enzyme activities were analyzed by kinetic spectrophotometric methods. Cytokines were analyzed with an antibody-based magnetic bead assay, PGE2 was assessed by ELISA, and Nrf-2, Bcl-2, Beclin 1, and the HSPs were analyzed by western blot. Autophagy levels were highlighted by fluorescence microscopy. The average IC50 dose for 6, 12, and 24 h was 16.1 ± 0.7 μg/mL. Although glutathione S-transferase and catalase were still upregulated after 24 h, superoxide dismutase was inhibited, which together allowed the gradual increase of malondialdehyde, anion superoxide, nitric oxide, and the loss of membrane integrity. G-CSF, IL-6, TNF-α, MIP-1β, MCP-1, Nrf-2, PGE2, and RANTES levels, as well as autophagy processes, were increased at all time intervals, as opposed to caspase 1 activity, COX-2, HSP60, and HSP70, which were only upregulated at the 6-h exposure interval. These results underscore that Si/SiO₂ QDs possess significant immunotoxic effects on the RAW 264.7 macrophage cell line and stress the importance of developing effective strategies to mitigate their adverse impact.

Multi-locus deletion mutation induced by silver nanoparticles: Role of lysosomal-autophagy dysfunction

Due to the rapid production growth and a wide range of applications, safety concerns are being raised about the genotoxic properties of silver nanoparticles (AgNPs). In this research, we found AgNPs induced a size-dependent genotoxicity via lysosomal-autophagy dysfunction in human-hamster hybrid (A_L) cells. Compared with 25 nm and 75 nm particles, 5 nm AgNPs could accentuate the genotoxic responses, including DNA double-strand breaks (DSBs) and multi-locus deletion mutation, which could be significantly enhanced by autophagy inhibitors 3-methyl adenine (3-MA), Bafilomycin A1 (BFA), and cathepsin inhibitors, respectively. The autophagy dysfunction was closely related to the accumulation of 5 nm AgNPs in the lysosomes and the interruption of lysosome-autophagosome fusion. With lysosomal protective agent 3-O-Methylsphingomyelin (3-O-M) and endocytosis inhibitor wortmannin, the reactivation of lysosomal function and the recovery of autophagy significantly attenuated AgNP-induced genotoxicity. Our data provide clear evidence to illustrate the role of subcellular targets in the genotoxicity of AgNPs in mammalian cells, which laid the basis for better understanding the health risk of AgNPs and their related products.

TRPM2 Mediates Hepatic Ischemia-Reperfusion Injury via Ca2+-Induced Mitochondrial Lipid Peroxidation through Increasing ALOX12 Expression

Hepatic ischemia-reperfusion (IR) injury is a serious clinical problem that complicates liver resection and transplantation. Despite recent advances in understanding of the pathophysiology of hepatic IR injury, effective interventions and therapeutics are still lacking. Here, we examined the role of transient receptor potential melastatin 2 (TRPM2), a Ca²⁺-permeable, non-selective cation channel, in mediating hepatic IR injury. Our data showed that TRPM2 deficiency attenuated IR-induced liver dysfunction, inflammation, and cell death in mice. Moreover, RNA sequencing analysis indicated that TRPM2-induced IR injury occurs via ferroptosis-related pathways. Consistently, as a ferroptosis inducer, (1S,3R)-RSL3 treatment induced mitochondrial dysfunction in hepatocytes and a TRPM2 inhibitor suppressed this. Interestingly, TRPM2-mediated calcium influx caused mitochondrial calcium accumulation via the mitochondrial Ca²⁺-selective uniporter and increased the expression level of arachidonate 12-lipoxygenase (ALOX12), which results in mitochondrial lipid peroxidation during hepatic IR injury. Furthermore, hepatic IR injury-induced ferroptosis was obviously relieved by a TRPM2 inhibitor or calcium depletion, both in vitro and in vivo. Collectively, these findings demonstrate a crucial role for TRPM2-mediated ferroptosis in hepatic IR injury via increased Ca²⁺-induced ALOX12 expression, indicating that pharmacological inhibition of TRPM2 may provide an effective therapeutic strategy for hepatic IR injury-related diseases, such as during liver resection and transplantation.

Lung inflammation perturbation by engineered nanoparticles

In recent years, the unique and diverse physicochemical properties of nanoparticles have brought about their wide use in many fields; however, it is necessary to better understand the possible human health risks caused by their release in the environment. Although the adverse health effects of nanoparticles have been proposed and are still being clarified, their effects on lung health have not been fully studied. In this review, we focus on the latest research progress on the pulmonary toxic effects of nanoparticles, and we summarized their disturbance of the pulmonary inflammatory response. First, the activation of lung inflammation by nanoparticles was reviewed. Second, we discussed how further exposure to nanoparticles aggravated the ongoing lung inflammation. Third, we summarized the inhibition of the ongoing lung inflammation by nanoparticles loaded with anti-inflammatory drugs. Forth, we introduced how the physicochemical properties of nanoparticles affect the related pulmonary inflammatory disturbance. Finally, we discussed the main gaps in current research and the challenges and countermeasures in future research.

Silica nanoparticles induce pulmonary damage in rats via VEGFC/D-VEGFR3 signaling-mediated lymphangiogenesis and remodeling

Silica nanoparticles (SiNPs) are widely used as drug carriers for improving drug delivery and retention. The lungs are highly sensitive to the toxicity of SiNPs entering the respiratory tract. Furthermore, pulmonary lymphangiogenesis, which is the growth of lymphatic vessels observed during multiple pulmonary diseases, plays a vital role in promoting the lymphatic transport of silica in the lungs. However, more research is required on the effects of SiNPs on pulmonary lymphangiogenesis. We investigated the effect of SiNP-induced pulmonary toxicity on lymphatic vessel formation in rats and evaluated the toxicity and possible molecular mechanisms of 20-nm SiNPs. Saline containing 3.0, 6.0, and 12.0mg/kg of SiNPs was instilled intrathecally into female Wistar rats once a day for five days, then sacrificed on day seven. Lung histopathology, pulmonary permeability, pulmonary lymphatic vessel density changes, and the ultrastructure of the lymph trunk were investigated using light microscopy, spectrophotometry, immunofluorescence, and transmission electron microscopy. CD45 expression in lung tissues was determined using immunohistochemical staining, and protein expression in the lung and lymph trunk was quantified using western blotting. We observed increased pulmonary inflammation and permeability, lymphatic endothelial cell damage, pulmonary lymphangiogenesis, and remodeling with increasing SiNP concentration. Moreover, SiNPs activated the VEGFC/D-VEGFR3 signaling pathway in the lung and lymphatic vessel tissues. SiNPs caused pulmonary damage, increased permeability and resulted in inflammation-associated lymphangiogenesis and remodeling by activating VEGFC/D-VEGFR3 signaling. Our findings provide evidence for SiNP-induced pulmonary damage and a new perspective for the prevention and treatment of occupational exposure to SiNPs. DATA AVAILABILITY: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.