Lysosomal nanotoxicity: Impact of nanomedicines on lysosomal function

Nanodiamonds Interact with Primary Human Macrophages and Dendritic Cells Evoking a Vigorous Interferon Response

Nanodiamonds (NDs) display several attractive features rendering them useful for medical applications such as drug delivery. However, the interactions between NDs and the immune system remain poorly understood. Here, we investigated amino-, carboxyl-, and poly(ethylene glycol) (PEG)-terminated NDs with respect to primary human immune cells. We applied cytometry by time-of-flight (CyToF) to assess the impact on peripheral blood mononuclear cells at the single-cell level, and observed an expansion of plasmacytoid dendritic cells (pDCs) which are critically involved in antiviral responses. Subsequent experiments demonstrated that the NDs were actively internalized, leading to a vigorous type I interferon response involving endosomal Toll-like receptors. ND-NH2 and ND-COOH were more potent than ND-PEG, as evidenced by using TLR reporter cell lines. Computational studies demonstrated that NDs interacted with the ligand-binding domains of TLR7 and TLR9 with high affinity though this was less pronounced for ND-PEG. NDs with varying surface functionalities were also readily taken up by macrophages. To gain further insight, we performed RNA sequencing of a monocyte-like cell line exposed to NDs, and found that the phagosome maturation pathway was significantly affected. Indeed, evidence for lysosomal hyperacidification was obtained in dendritic cells and macrophages exposed to NDs. Moreover, using a reporter cell line, NDs were found to impinge on autophagic flux. However, NDs did not affect viability of any of the cell types studied. This study has shown that NDs subvert dendritic cells leading to an antiviral-like immune response. This has implications not only for drug delivery but also for anticancer vaccines using NDs.

Catalase-encapsulated matrix metalloproteinase-9 responsive nanogels for modulation of inflammatory response and treatment of neutrophilic asthma

Asthma is a chronic disease with typical pathological features such as airflow limitation, airway inflammation and remodeling. Of these, neutrophilic asthma is considered to be the more severe and corticosteroid-resistant subtype of asthma. Increasing evidence suggests that patients with neutrophilic asthma often accompany with dysbiosis of the internal microbiota, where the increased abundance of non-typeable Haemophilus influenzae (NTHi) is closely related to the neutrophilic asthma phenotype. Furthermore, emerging evidence suggests that reactive oxygen species (ROS) are pivotal in the pathogenesis of neutrophilic asthma. In this study, matrix metalloproteinase-9 (MMP-9)-responsive, catalase-loaded nanogels (M-CAT-NGs) were synthesized, which was composed of MMP-9-sensitive peptide (VPMS), arginine-grafted chitosan and maleimide (CS-Arg-Mal), catalase (CAT), sodium citrate (SC) and ε-poly(L-lysine) (ε-PLL). The M-CAT-NGs showed potent antimicrobial effects and exerted excellent therapeutic effects in the presence of MMP-9 by causing VPMS rupture and responsive release of CAT. In vitro experiments revealed that M-CAT-NGs effectively inhibited the proliferation of NTHi, Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli), while also demonstrating the capacity to modulate the inflammatory response induced by lipopolysaccharide (LPS) and hydrogen peroxide (H2O2) stimulation. In vivo experiments demonstrated that nebulized inhalation of M-CAT-NGs was effective in reducing airway hyperresponsiveness (AHR), alleviating inflammation, downregulating the expression level of ROS in the lung tissues, thus enabling the effective management of neutrophilic asthma. Thus, the development of M-CAT-NGs has shown strong potential for the clinical management of neutrophilic asthma by modulating the inflammatory response.

DNA Nanostructures for Rational Regulation of Cellular Organelles

DNA nanotechnology has revolutionized materials science and biomedicine by enabling precise manipulation of matter at the nanoscale. DNA nanostructures (DNs) in particular represent a promising frontier for targeted therapeutics. Engineered DNs offer unprecedented molecular programmability, biocompatibility, and structural versatility, making them ideal candidates for advanced drug delivery, organelle regulation, and cellular function modulation. This Perspective explores the emerging role of DNs in modulating cellular behavior through organelle-targeted interventions. We highlight current advances in nuclear, mitochondrial, and lysosomal targeting, showcasing applications ranging from gene delivery to cancer therapeutics. For instance, DNs have enabled precision mitochondrial disruption in cancer cells, lysosomal pH modulation to enhance gene silencing, and nuclear delivery of gene-editing templates. While DNs hold immense promise for advancing nanomedicine, outstanding challenges include optimizing biological interactions and addressing safety concerns. This Perspective highlights the current potential of DNs for rational control of targeted organelles, which could lead to novel therapeutic strategies and advancement of precision nanomedicines in the future.

Nanoparticle-Mediated Embryotoxicity: Mechanisms of Chemical Toxicity and Implications for Biological Development

Nanoparticles, defined by their nanoscale dimensions and unique physicochemical properties, are widely utilized in healthcare, electronics, environmental sciences, and consumer products. However, increasing evidence of their potential embryotoxic effects during pregnancy underscores the need for a molecular-level understanding of their interactions during embryonic development. Nanoparticles such as titanium dioxide, silver, cerium oxide, copper oxide, and quantum dots can cross the placental barrier and interfere with crucial developmental processes. At the molecular level, they disrupt signaling pathways like Wnt and Hedgehog, induce oxidative stress and inflammation, and cause genotoxic effects, all critical during sensitive phases, such as organogenesis. Furthermore, these nanoparticles interact directly with cellular components, including DNA, proteins, and lipids, impairing cellular function and viability. Innovative strategies to mitigate nanoparticle toxicity, such as surface modifications and incorporation of biocompatible coatings, are discussed as potential solutions to reduce adverse molecular interactions. Various laboratory animal models used to investigate nanoparticle-induced embryotoxicity are evaluated for their efficacy and limitations, providing insights into their applicability for understanding these effects. This Account examines the molecular mechanisms by which nanoparticles compromise embryonic development and emphasizes the importance of designing safer nanoparticles to minimize maternal-fetal exposure risks, particularly in biomedical applications.

Robust Acid-Responsive AILE Luminescence Effect Nanoparticle for Drug Release Monitoring and Induction of Apoptosis in Cancer Cells

Through the PFOEP-SO3(-) + multidrug molecules constructed nanoparticle (NP) experiments and validated by molecular simulation docking experiments, we propose a molecular interaction principle for inducing aggregation-induced locally excited emission (AILE) luminescence from fluorenone (FO)-based conjugated polymers (CPs). Based on this molecular interaction mechanism, we constructed a NP built by π-π stacking. The NPs demonstrate facile synthesis, robust stability, and high drug-loading efficiency, enabling tumor-specific drug release in acidic lysosomal environments (pH 3.8-4.7) to minimize off-target toxicity. Concurrently, the PFOEPA NPs exhibit pH-dependent fluorescence enhancement: drug incorporation induces structural reorganization into a "sandwich" configuration, amplifying fluorescence with a blue shift under neutral/alkaline conditions, while acidic-triggered protonation collapse disrupts NPs. Moreover, it can be used as an indicator for monitoring drug release, as it is accompanied by changes in fluorescence during the drug release process. This NP possesses multiple functions and is expected to serve as an effective pH-responsive drug delivery system.

Mechanistic Insights into Sphingomyelin Nanoemulsions as Drug Delivery Systems for Non-Small Cell Lung Cancer Therapy

Sphingomyelin nanoemulsions (SNs) are promising drug delivery systems with potential for treating challenging tumors, including non-small cell lung cancer (NSCLC), which has a poor prognosis and a 5-year survival rate below 5%. Understanding the toxicity mechanisms and intracellular behavior of SNs is crucial for optimizing their therapeutic application. This study aims to investigate the interaction between SNs and A549 lung adenocarcinoma cells, focusing on their cytotoxic effects and mechanisms of cellular toxicity. SNs were synthesized and characterized for size, surface charge, and stability. A549 cells were treated with varying concentrations of SNs, and cellular uptake pathways were assessed using inhibitors of energy-dependent processes. Cytotoxicity was evaluated through an alamarBlue assay to determine the IC50 value after 24 h. Mechanisms of toxicity, including lysosomal and mitochondrial involvement, were examined using co-localization studies, mitochondrial membrane potential assays, and markers of apoptosis. SNs exhibited rapid cellular uptake via energy-dependent pathways. The IC50 concentration for A549 cells was 0.89 ± 0.15 mg/mL, suggesting favorable cytocompatibility compared to other nanocarriers. At IC50, SNs induced apoptosis characterized by lysosomal damage, mitochondrial membrane permeabilization, and the release of apoptotic factors. These effects disrupted autophagic flux and contributed to cell death, demonstrating potential for overcoming drug resistance. Resveratrol-loaded SNs showed enhanced cytotoxicity, supporting their application as targeted drug delivery vehicles. This study highlights the potential of SNs as efficient drug delivery systems for NSCLC therapy, offering insights into their cellular interactions and toxicity mechanisms. These findings pave the way for the rational design of SN-based therapeutic platforms for cancer and other mitochondria-related diseases.

Geometrically constrained cytoskeletal reorganisation modulates DNA nanostructures uptake

DNA nanostructures (DNs) have gained popularity in various biomedical applications due to their unique properties, including structural programmability, ease of synthesis and functionalization, and low cytotoxicity. Effective utilization of DNs in biomedical applications requires a fundamental understanding of their interactions with living cells and the mechanics of cellular uptake. Current knowledge primarily focuses on how the physicochemical properties of DNs, such as mass, shape, size, and surface functionalization, affect uptake efficacy. However, the role of cellular mechanics and morphology in DN uptake remains largely unexplored. In this work, we show that cells subjected to geometric constraints remodel their actin cytoskeleton, resulting in differential mechanical force generation that facilitates DN uptake. The length, number, and orientation of F-actin fibers are influenced by these constraints, leading to distinct mechanophenotypes. Overall, DN uptake is governed by F-actin forces arising from filament reorganisation under geometric constraints. These results underscore the importance of actin dynamics in the cellular uptake of DNs and suggest that leveraging geometric constraints to induce specific cell morphology adaptations could enhance the uptake of therapeutically designed DNs.

Investigation of oral toxicity of WS2 nanosheets to mouse intestine: Pathological injury, trace element balance, lipid profile changes, and autophagy

The success of graphene oxides has gained extensive research interests in developing novel 2D nanomaterials (NMs). WS2 nanosheets (NSs) are novel transition metal-based 2D NMs, but their toxicity is unclear. In this study, we investigated the oral toxicity of WS2 NSs to mouse intestines. Male mice were administrated with vehicles, 1, 10, or 100 mg/kg NSs via intragastric route, once a day, for 5 days. The results indicate that the NSs did not induce pathological or ultrastructural changes in intestines. There were minimal changes of trace elements that the exposure did not induce W accumulation, and only Co levels were dose-dependently increased. Lipid droplets were observed in all groups of mice, but lipidomics data indicate that WS2 NSs only significantly decreased four lipid species, all belonging to phosphatidylcholine (PC). The levels of proteins regulating autophagic lipolysis, namely, LC3, lysosomal associated membrane protein 2 (LAMP2) and perilipin 2 (PLIN2), were increased, but it was only statistically significantly different for LC3. The results of this study suggest that repeated intragastric exposure to WS2 NSs only induced minimal influences on pathological injury, trace element balance, autophagy, and lipid profiles in mouse intestines, indicating relatively high biocompatibility of WS2 NSs to mouse intestine via oral route.

Cationic and anionic PLGA-cholesterol hybrid nanoparticles as promising platforms to enhance the trypanocidal efficacy of benznidazole and drug delivery in Trypanosoma cruzi-infected cells

Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi, remains a significant global health challenge. Currently, benznidazole (BNZ) is the primary treatment in many countries. However, this drug is limited by low bioavailability, significant host toxicity, and reduced efficacy in chronic disease phase. Additionally, cases of parasite resistance to treatment and low efficacy in in chronic disease phase have been reported. In this context, nanotechnology formulations for intracellular drug delivery have emerged as a promising alternative to improve the pharmacological properties of BNZ. In this study, we developed and evaluated cationic and anionic PLGA-cholesterol hybrid nanoparticles (HNPs) as innovative drug delivery systems for BNZ. These HNPs, functionalized with polyethyleneimine, were synthesized using a composition-dependent self-assembly method, yielding stable nanosystems with tuneable physicochemical properties. Furthermore, four release kinetic models were applied and Peppas-Sahlin demonstrated the best fit. In vitro assays confirmed the biocompatibility of HNPs with cardiomyoblasts at tested concentrations and revealed significantly enhanced trypanocidal activity against intracellular amastigotes compared to free BNZ. Transmission electron microscopy and fluorescence microscopy analyses highlighted effective nanoparticle internalization, with superior performance trypanocidal observed in anionic HNPs, which can be attributed to the residence of cationic in endo/lysosomal vesicles. Taken together, our results demonstrate the successful development of HNPs, underscoring their potential as a promising platform for the intracellular delivery of therapeutic agents.

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.

Mitophagy and its regulatory mechanisms in the biological effects of nanomaterials

Mitophagy is a selective cellular process critical for the removal of damaged mitochondria. It is essential in regulating mitochondrial number, ensuring mitochondrial functionality, and maintaining cellular equilibrium, ultimately influencing cell destiny. Numerous pathologies, such as neurodegenerative diseases, cardiovascular disorders, cancers, and various other conditions, are associated with mitochondrial dysfunctions. Thus, a detailed exploration of the regulatory mechanisms of mitophagy is pivotal for enhancing our understanding and for the discovery of novel preventive and therapeutic options for these diseases. Nanomaterials have become integral in biomedicine and various other sectors, offering advanced solutions for medical uses including biological imaging, drug delivery, and disease diagnostics and therapy. Mitophagy is vital in managing the cellular effects elicited by nanomaterials. This review provides a comprehensive analysis of the molecular mechanisms underpinning mitophagy, underscoring its significant influence on the biological responses of cells to nanomaterials. Nanoparticles can initiate mitophagy via various pathways, among which the PINK1-Parkin pathway is critical for cellular defense against nanomaterial-induced damage by promoting mitophagy. The role of mitophagy in biological effects was induced by nanomaterials, which are associated with alterations in Ca2+ levels, the production of reactive oxygen species, endoplasmic reticulum stress, and lysosomal damage.

Advances in drug-induced liver injury research: in vitro models, mechanisms, omics and gene modulation techniques

Drug-induced liver injury (DILI) refers to drug-mediated damage to the structure and function of the liver, ranging from mild elevation of liver enzymes to severe hepatic insufficiency, and in some cases, progressing to liver failure. The mechanisms and clinical symptoms of DILI are diverse due to the varying combination of drugs, making clinical treatment and prevention complex. DILI has significant public health implications and is the primary reason for post-marketing drug withdrawals. The search for reliable preclinical models and validated biomarkers to predict and investigate DILI can contribute to a more comprehensive understanding of adverse effects and drug safety. In this review, we examine the progress of research on DILI, enumerate in vitro models with potential benefits, and highlight cellular molecular perturbations that may serve as biomarkers. Additionally, we discuss omics approaches frequently used to gather comprehensive datasets on molecular events in response to drug exposure. Finally, three commonly used gene modulation techniques are described, highlighting their application in identifying causal relationships in DILI. Altogether, this review provides a thorough overview of ongoing work and approaches in the field of DILI.

Peptide-coated DNA nanostructures as a platform for control of lysosomal function in cells

DNA nanotechnology is a rapidly growing field that provides exciting tools for biomedical applications. Targeting lysosomal functions with nanomaterials, such as DNA nanostructures (DNs), represents a rational and systematic way to control cell functionality. Here we present a versatile DNA nanostructure-based platform that can modulate a number of cellular functions depending on the concentration and surface decoration of the nanostructure. Utilizing different peptides for surface functionalization of DNs, we were able to rationally modulate lysosomal activity, which in turn translated into the control of cellular function, ranging from changes in cell morphology to modulation of immune signaling and cell death. Low concentrations of decalysine peptide-coated DNs induced lysosomal acidification, altering the metabolic activity of susceptible cells. In contrast, DNs coated with an aurein-bearing peptide promoted lysosomal alkalization, triggering STING activation. High concentrations of decalysine peptide-coated DNs caused lysosomal swelling, loss of cell-cell contacts, and morphological changes without inducing cell death. Conversely, high concentrations of aurein-coated DNs led to lysosomal rupture and mitochondrial damage, resulting in significant cytotoxicity. Our study holds promise for the rational design of a new generation of versatile DNA-based nanoplatforms that can be used in various biomedical applications, like the development of combinatorial anti-cancer platforms, efficient systems for endolysosomal escape, and nanoplatforms modulating lysosomal pH.

Black phosphorus nanosheets induce autophagy dysfunction by a size- and surface modification-related impairment of lysosomes in macrophages

The widespread application of black phosphorus nanosheets (BPNSs) raises concerns about their potential impact on human health. Although that the autophagy-inducing properties of BPNSs in cancer cells are documented, their effects on macrophages-key components of the immune system and the mechanisms involved remain obscure, especially in terms of the influences of BPNS the size and surface modifications on the autophagic process. This study investigated the effects of bare BPNSs and PEGylated BPNSs (BP-PEG) on macrophage autophagy and its underlying mechanisms by comprehensive biochemical analyses. The results indicated that both BPNSs and BP-PEG are internalized by RAW264.7 cells through phagocytosis and caveolin-dependent endocytosis, leading to lysosomal accumulation. The internalized BPNSs induced mitochondrial dysfunction, which subsequently elevated the NAD+/NADH ratio and activated the SIRT-1 pathway, initiating autophagy. However, BPNSs disrupted the autophagic flux by impairing autolysosome formation, leading to apoptosis in a size-dependent manner. In contrast, BP-PEG preserved lysosomal integrity, maintaining autophagic activity and cell viability. These findings deepen our understanding of the influence of nanosheet size and surface modifications on macrophage autophagy, contributing to the formulation of regulatory guidelines to minimize the potential adverse effects and health risks associated with BPNS utilization in various applications.

Impact of mechanical cues on key cell functions and cell-nanoparticle interactions

In recent years, it has been recognized that mechanical forces play an important regulative role in living organisms and possess a direct impact on crucial cell functions, ranging from cell growth to maintenance of tissue homeostasis. Advancements in mechanobiology have revealed the profound impact of mechanical signals on diverse cellular responses that are cell type specific. Notably, numerous studies have elucidated the pivotal role of different mechanical cues as regulatory factors influencing various cellular processes, including cell spreading, locomotion, differentiation, and proliferation. Given these insights, it is unsurprising that the responses of cells regulated by physical forces are intricately linked to the modulation of nanoparticle uptake kinetics and processing. This complex interplay underscores the significance of understanding the mechanical microenvironment in shaping cellular behaviors and, consequently, influencing how cells interact with and process nanoparticles. Nevertheless, our knowledge on how localized physical forces affect the internalization and processing of nanoparticles by cells remains rather limited. A significant gap exists in the literature concerning a systematic analysis of how mechanical cues might bias the interactions between nanoparticles and cells. Hence, our aim in this review is to provide a comprehensive and critical analysis of the existing knowledge regarding the influence of mechanical cues on the complicated dynamics of cell-nanoparticle interactions. By addressing this gap, we would like to contribute to a detailed understanding of the role that mechanical forces play in shaping the complex interplay between cells and nanoparticles.

Comparative time-dependent proteomics reveal the tolerance of cancer cells to magnetic iron oxide nanoparticles

Cancer is one of the most challenging diseases in the world. Recently, iron oxide nanoparticles (IONPs) are emerging materials with rapid development and high application value, and have shown great potential on tumor therapy due to their unique magnetic and biocompatible properties. However, some data hint us that IONPs were toxic to normal cells and vital organs. Thus, more data on biosafety evaluation is urgently needed. In this study, we compared the effects of silicon-coated IONPs (Si-IONPs) on two cell types: the tumor cells (Hela) and the normal cells (HEK293T, as 293 T for short), compared differences of protein composition, allocation and physical characteristics between these two cells. The major findings of our study pointed out that 293 T cells death occurred more significant than that of Hela cells after Si-IONPs treatment, and the rate and content of endocytosis of Si-IONPs in 293 T cells was more prominent than in Hela cells. Our results also showed Si-IONPs significant promoted the production of reactive oxygen species and disturbed pathways related to oxidative stress, iron homeostasis, apoptosis and ferroptosis in both two types of cells, however, Hela cells recovered from these disturbances more easily than 293 T. In conclusion, compared with Hela cells, IONPs are more likely to induce 293 T cells death and Hela cells have their own unique mechanisms to defense invaders, reminding scientists that future in vivo and in vitro studies of nanoparticles need to be cautious, and more safety data are needed for further clinical treatment.

In vitro evaluation of physicochemical-dependent effects of polymeric nanoparticles on their cellular uptake and co-localization using pulmonary calu-3 cell lines

OBJECTIVE

The study evaluated physicochemical properties of eight different polymeric nanoparticles (NPs) and their interaction with lung barrier and their suitability for pulmonary drug delivery.

METHODS

Eight physiochemically different NPs were fabricated from Poly lactic-co-glycolic acid (PLGA, PL) and Poly glycerol adipate-co-ω-pentadecalactone (PGA-co-PDL, PG) via emulsification-solvent evaporation. Pulmonary barrier integrity was investigated in vitro using Calu-3 under air-liquid interface. NPs internalization was investigated using a group of pharmacological inhibitors with subsequent microscopic visual confirmation.

RESULTS

Eight NPs were successfully formulated from two polymers using emulsion-solvent evaporation; 200, 500 and 800 nm, negatively-charged and positively-charged. All different NPs did not alter tight junctions and PG NPs showed similar behavior to PL NPs, indicating its suitability for pulmonary drug delivery. Active endocytosis uptake mechanisms with physicochemical dependent manner were observed. In addition, NPs internalization and co-localization with lysosomes were visually confirmed indicating their vesicular transport.

CONCLUSION

PG and PL NPs had shown no or low harmful effects on the barrier integrity, and with effective internalization and vesicular transport, thus, prospectively can be designed for pulmonary delivery applications.

Nanotheranostics in cancer lymph node metastasis: The long road ahead

Lymph node metastasis (LNM) significantly impacts the prognosis of cancer patients. Despite significant advancements in diagnostic techniques and treatment modalities, clinical challenges continue to persist in the realm of LNM. These include difficulties in early diagnosis, limited treatment efficacy, and potential side effects and injuries associated with treatment. Nanotheranostics, a field within nanotechnology, seamlessly integrates diagnostic and therapeutic functionalities. Its primary goal is to provide precise and effective disease diagnosis and treatment simultaneously. The development of nanotheranostics for LNM offers a promising solution for the stratified management of patients with LNM and promotes the advancement of personalized medicine. This review introduces the mechanisms of LNM and challenges in its diagnosis and treatment. Furthermore, it demonstrates the advantages and development potential of nanotheranostics, focuses on the challenges nanotheranostics face in its application, and provides an outlook on future trends. We consider nanotheranostics a promising strategy to improve clinical effectiveness and efficiency as well as the prognosis of cancer patients with LNM.

Strategies and Progress of Raman Technologies for Cellular Uptake Analysis of the Drug Delivery Systems

Nanoparticle (NP)-based drug delivery systems have the potential to significantly enhance the pharmacological and therapeutic properties of drugs. These systems enhance the bioavailability and biocompatibility of pharmaceutical agents via enabling targeted delivery to specific tissues or organs. However, the efficacy and safety of these systems are largely dependent on the cellular uptake and intracellular transport of NPs. Thus, it is crucial to monitor the intracellular behavior of NPs within a single cell. Yet, it is challenging due to the complexity and size of the cell. Recently, the development of the Raman instrumentation offers a versatile tool to allow noninvasive cellular measurements. The primary objective of this review is to highlight the most recent advancements in Raman techniques (spontaneous Raman scattering, bioorthogonal Raman scattering, coherence Raman scattering, and surface-enhanced Raman scattering) when it comes to assessing the internalization of NP-based drug delivery systems and their subsequent movement within cells.

Dual Implications of Nanosilver-Induced Autophagy: Nanotoxicity and Anti-Cancer Effects

In recent years, efforts have been made to identify new anti-cancer therapies. Various types of nanomaterials, including silver nanoparticles (AgNPs), are being considered as an option. In addition to its well-known antibacterial activity, AgNPs exhibit cytotoxic potential in both physiological and cancer cells by inducing stress-mediated autophagy and apoptotic cell death. A rapidly growing collection of data suggests that the proper regulation of autophagic machinery may provide an efficient tool for suppressing the development of cancer. In this light, AgNPs have emerged as a potential anti-cancer agent to support therapy of the disease. This review summarizes current data indicating the dual role of AgNP-induced autophagy and highlights factors that may influence its protective vs. its toxic potential. It also stresses that our understanding of the cellular and molecular mechanisms of autophagy machinery in cancer cells, as well as AgNP-triggered autophagy in both normal and diseased cells, remains insufficient.

Challenges of current treatment and exploring the future prospects of nanoformulations for treatment of atopic dermatitis

Atopic dermatitis (AD) is a predominant and deteriorating chronic inflammation of the skin, categorized by a burning sensation and eczematous lesions in diverse portions of the body. The treatment of AD is exclusively focused to limit the itching, reduce inflammation, and repair the breached barrier of the skin. Several therapeutic agents for the treatment and management of AD have been reported and are in use in clinics. However, the topical treatment of AD has been an unswerving challenge for the medical fraternity owing to the impaired skin barrier function in this chronic skin condition. To surmount the problems of conventional drug delivery systems, numerous nanotechnology-based formulations are emerging as alternative new modalities for AD. Latter enhances the bioavailability and delivery to the target disease site, improves drug permeation and therapeutic efficacy with reduced systemic and off-target side effects, and thus improves patient health and promotes compliance. This review aims to describe the various pathophysiological events involved in the occurrence of AD, current challenges in treatment, evidence of molecular markers of AD and its management, combinatorial treatment options, and the intervention of nanotechnology-based formulations for AD therapeutics.

Iron oxide nanoparticles trigger endoplasmic reticulum damage in steatotic hepatic cells

Iron oxide nanoparticles (IONPs) are being actively researched in various biomedical applications, particularly as magnetic resonance imaging (MRI) contrast agents for diagnosing various liver pathologies like nonalcoholic fatty liver diseases, nonalcoholic steatohepatitis, and cirrhosis. Emerging evidence suggests that IONPs may exacerbate hepatic steatosis and liver injury in susceptible livers such as those with nonalcoholic fatty liver disease. However, our understanding of how IONPs may affect steatotic cells at the sub-cellular level is still fragmented. Generally, there is a lack of studies identifying the molecular mechanisms of potential toxic and/or adverse effects of IONPs on "non-heathy" in vitro models. In this study, we demonstrate that IONPs, at a dose that does not cause general toxicity in hepatic cells (Alexander and HepG2), induce significant toxicity in steatotic cells (cells loaded with non-toxic doses of palmitic acid). Mechanistically, co-treatment with PA and IONPs resulted in endoplasmic reticulum (ER) stress, accompanied by the release of cathepsin B from lysosomes to the cytosol. The release of cathepsin B, along with ER stress, led to the activation of apoptotic cell death. Our results suggest that it is necessary to consider the interaction between IONPs and the liver, especially in susceptible livers. This study provides important basic knowledge for the future optimization of IONPs as MRI contrast agents for various biomedical applications.