This book provides an overview on the molecular mode of action of carcinogenic polycyclic aromatic hydrocarbons (PAHs). PAHs are by-products arising from incomplete combustion of organic matter that ...are frequently released into our environment, and thus are ubiquitously detectable. Many PAHs are strong carcinogens in rodent bioassays and have been linked to increased incidences of various types of cancer in humans. The present book covers all aspects of PAH-induced carcinogenesis; it is a collection of articles written by some of the most recognizable PAH researchers, reviewing the present knowledge in this field. The topics include: exposure to and biomonitoring of PAHs in the human population; metabolic activation of PAHs; genotoxicity and repair of PAH-induced DNA damage; and factors modulating individual susceptibility to the deleterious effects of PAHs.
Nanosilver, due to its small particle size and enormous specific surface area, facilitates more rapid dissolution of ions than the equivalent bulk material; potentially leading to increased toxicity ...of nanosilver. This, coupled with their capacity to adsorb biomolecules and interact with biological receptors can mean that nanoparticles can reach sub-cellular locations leading to potentially higher localized concentrations of ions once those particles start to dissolve or degrade
. Further complicating the story is the capacity for nanoparticles to generate reactive oxygen species, and to interact with, and potentially disturb the functioning of biomolecules such as proteins, enzymes and DNA. The fact that the nanoparticle size, shape, surface coating and a host of other factors contribute to these interactions, and that the particles themselves are evolving or ageing leads to further complications in terms of elucidating mechanisms of interaction and modes of action for silver nanoparticles, in contrast to dissolved silver species. This review aims to provide a critical assessment of the current understanding of silver nanoparticle toxicity, as well as to provide a set of pointers and guidelines for experimental design of future studies to assess the environmental and biological impacts of silver nanoparticles. In particular; in future we require a detailed description of the nanoparticles; their synthesis route and stabilisation mechanisms; their coating; and evolution and ageing under the exposure conditions of the assay. This would allow for comparison of data from different particles; different environmental or biological systems; and structure-activity or structure-property relationships to emerge as the basis for predictive toxicology. On the basis of currently available data; such comparisons or predictions are difficult; as the characterisation and time-resolved data is not available; and a full understanding of silver nanoparticle dissolution and ageing under different conditions is observed. Clear concerns are emerging regarding the overuse of nanosilver and the potential for bacterial resistance to develop. A significant conclusion includes the need for a risk-benefit analysis for all applications and eventually restrictions of the uses where a clear benefit cannot be demonstrated.
Advances in nanomedicine, coupled with novel methods of creating advanced materials at the nanoscale, have opened new perspectives for the development of healthcare and medical products. Special ...attention must be paid toward safe design approaches for nanomaterial‐based products. Recently, artificial intelligence (AI) and machine learning (ML) gifted the computational tool for enhancing and improving the simulation and modeling process for nanotoxicology and nanotherapeutics. In particular, the correlation of in vitro generated pharmacokinetics and pharmacodynamics to in vivo application scenarios is an important step toward the development of safe nanomedicinal products. This review portrays how in vitro and in vivo datasets are used in in silico models to unlock and empower nanomedicine. Physiologically based pharmacokinetic (PBPK) modeling and absorption, distribution, metabolism, and excretion (ADME)‐based in silico methods along with dosimetry models as a focus area for nanomedicine are mainly described. The computational OMICS, colloidal particle determination, and algorithms to establish dosimetry for inhalation toxicology, and quantitative structure–activity relationships at nanoscale (nano‐QSAR) are revisited. The challenges and opportunities facing the blind spots in nanotoxicology in this computationally dominated era are highlighted as the future to accelerate nanomedicine clinical translation.
Artificial intelligence and machine learning in computational nanomedicine are making great strides in nanoparticle‐modified theranostics design and development. The quantitative structure–activity relationships at nanoscale, physiologically based pharmacokinetic, absorption, distribution, metabolism, and excretion, and dosimetry‐based advanced computational models further help in understanding the in vitro physiological and pharmacokinetics and correlate the data with in vivo scenario. This review focuses on recent advances in computational modeling unlocking and empowering nanotoxicology.
The human aryl hydrocarbon receptor (AHR) undergoes continuous shuttling between nucleus and cytoplasm. Binding to exogenous or endogenous ligands promotes its rapid nuclear import. The proposed ...mechanism for the ligand-dependent import is based on exposing the bipartite nuclear localisation signal (NLS) to members of the importin (IMP) superfamily. Among this, the molecular interactions involved in the basal import still need to be clarified. Utilizing fluorescently fused AHR variants, we recapitulated and characterized AHR localization and nucleo-cytoplasmic shuttling in living cells. Analysis of AHR variants carrying NLS point mutations demonstrated a mandatory role of first (13RKRRK17) and second (37KR-R40) NLS segments on the basal import of AHR. Further experiments indicated that ligand-induced import is mainly regulated through the first NLS, while the second NLS is supportive but not essential. Additionally, applying IMPα/β specific inhibitors, ivermectin (IVM) and importazole (IPZ), slowed down the ligand-induced import and, correspondingly, decreased the basal nuclear accumulation of the receptor. In conclusion, our data show that ligand-induced and basal nuclear entry of AHR rely on the same mechanism but are controlled uniquely by the two NLS components.
In the body, nanoparticles can be systemically distributed and then may affect secondary target organs, such as the central nervous system (CNS). Putative adverse effects on the CNS are rarely ...investigated to date. Here, we used a mixed primary cell model consisting mainly of neurons and astrocytes and a minor proportion of oligodendrocytes to analyze the effects of well-characterized 20 and 40 nm silver nanoparticles (SNP). Similar gold nanoparticles served as control and proved inert for all endpoints tested. SNP induced a strong size-dependent cytotoxicity. Additionally, in the low concentration range (up to 10 μg/ml of SNP), the further differentiated cultures were more sensitive to SNP treatment. For detailed studies, we used low/medium dose concentrations (up to 20 μg/ml) and found strong oxidative stress responses. Reactive oxygen species (ROS) were detected along with the formation of protein carbonyls and the induction of heme oxygenase-1. We observed an acute calcium response, which clearly preceded oxidative stress responses. ROS formation was reduced by antioxidants, whereas the calcium response could not be alleviated by antioxidants. Finally, we looked into the responses of neurons and astrocytes separately. Astrocytes were much more vulnerable to SNP treatment compared with neurons. Consistently, SNP were mainly taken up by astrocytes and not by neurons. Immunofluorescence studies of mixed cell cultures indicated stronger effects on astrocyte morphology. Altogether, we can demonstrate strong effects of SNP associated with calcium dysregulation and ROS formation in primary neural cells, which were detectable already at moderate dosages.
Introduction: There is growing emphasis on the development of bioinspired and biohybrid micro/nanorobots for the targeted drug delivery (TDD). Particularly, stimuli-responsive materials and ...magnetically triggered systems, identified as the most promising materials and design paradigms. Despite the advances made in fabrication and control, there remains a significant gap in clinical translation.
Areas covered: This review discusses the opportunities and challenges about micro/nanorobotics for the TDD as evolutionary evidence in bio-nanotechnology, material science, biohybrid robotics, and many more. Important consideration in context with the material's compatibility/immunogenicity, ethics, and security risk are reported based on the development in artificial intelligence (AI)/machine learning described in literature. The versatility and sophistication of biohybrid components design are being presented, highlighting stimuli-responsive biosystems as smart mechanisms and on-board sensing and control elements.
Expert opinion: Focusing on key issues for high controllability at micro- and nano-scale systems in TDD, biohybrid integration strategies, and bioinspired key competences shall be adopted. The promising outlook portraying the commercialization potential and economic viability of micro/nanorobotics will benefit to clinical translation.
More information about a person's genetic makeup, drug response, multi-omics response, and genomic response is now available leading to a gradual shift towards personalized treatment. Additionally, ...the promotion of non-animal testing has fueled the computational toxicogenomics as a pivotal part of the next-gen risk assessment paradigm. Artificial Intelligence (AI) has the potential to provid new ways analyzing the patient data and making predictions about treatment outcomes or toxicity. As personalized medicine and toxicogenomics involve huge data processing, AI can expedite this process by providing powerful data processing, analysis, and interpretation algorithms. AI can process and integrate a multitude of data including genome data, patient records, clinical data and identify patterns to derive predictive models anticipating clinical outcomes and assessing the risk of any personalized medicine approaches. In this article, we have studied the current trends and future perspectives in personalized medicine & toxicology, the role of toxicogenomics in connecting the two fields, and the impact of AI on personalized medicine & toxicology. In this work, we also study the key challenges and limitations in personalized medicine, toxicogenomics, and AI in order to fully realize their potential.
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•Established the relationship between personalized medicine and toxicology.•Outlined the importance of artificial intelligence in the current clinical decision-making process.•Overview of the various bottlenecks in artificial intelligence applications.•Provided a roadmap to future researchers on integrating precision medicine, toxicology and artificial intelligence.
Nanotoxicology and nanosafety has been a topic of intensive research for about more than 20 years. Nearly 10 000 research papers have been published on the topic, yet there exists a gap in terms of ...understanding and ways to harmonize nanorisk assessment. In this review, we revisit critically ignored parameters of nanoscale materials (e.g. band gap factor, phase instability and silver leaching problem, defect and instability plasmonic versus inorganic particles) versus their biological counterparts (cell batch-to-batch heterogeneity, biological barrier model design, cellular functional characteristics) which yield variability and nonuniformity in results. We also emphasize system biology approaches to integrate the high throughput screening methods coupled with in vivo and in silico modeling to ensure quality in nanosafety research. We emphasize and highlight the recommendation regarding bridging the mechanistic gaps in fundamental research and predictive biological response in nanotoxicology. The research community has to develop visions to predict the unforeseen problems that do not exist yet in context with nanotoxicity and public health hazards due to the burgeoning use of nanomaterial in consumer's product.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this study, we determined partition (Ksc/m) and diffusion (Dsc) coefficients of five different polycyclic aromatic hydrocarbons (PAH) migrating from squalane into and through the stratum corneum ...(s.c.) layer of the skin. Carcinogenic PAH have previously been detected in numerous polymer-based consumer products, especially those dyed with carbon black. Upon dermal contact with these products, PAH may penetrate into and through the viable layers of the skin by passing the s.c. and thus may become bioavailable. Squalane, a frequent ingredient in cosmetics, has also been used as a polymer surrogate matrix in previous studies. Ksc/m and Dsc are relevant parameters for risk assessment because they allow estimating the potential of a substance to become bioavailable upon dermal exposure. We developed an analytical method involving incubation of pigskin with naphthalene, anthracene, pyrene, benzoapyrene and dibenzoa,hpyrene in Franz diffusion cell assays under quasi-infinite dose conditions. PAH were subsequently quantified within individual s.c. layers by gas chromatography coupled to tandem mass spectrometry. The resulting PAH depth profiles in the s.c. were fitted to a solution of Fick’s second law of diffusion, yielding Ksc/m and Dsc. The decadic logarithm logKsc/m ranged from −0.43 to +0.69 and showed a trend to higher values for PAH with higher molecular masses. Dsc, on the other hand, was similar for the four higher molecular mass PAH but about 4.6-fold lower than for naphthalene. Moreover, our data suggests that the s.c./viable epidermis boundary layer represents the most relevant barrier for the skin penetration of higher molecular mass PAH. Finally, we empirically derived a mathematical description of the concentration depth profiles that better fits our data. We correlated the resulting parameters to substance specific constants such as the logarithmic octanol-water partition coefficient logP, Ksc/m and the removal rate at the s.c./viable epidermis boundary layer.
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•First experimental data on diffusion of different PAH through the stratum corneum.•Partition of PAH from squalane into the stratum corneum correlates with logP.•Diffusion coefficients of PAH in the stratum corneum hit threshold at three condensed rings.•Alternative empirical mathematical description of diffusion presented for relevant PAH.
The health risks of tobacco smoking have been documented in numerous studies and smoking rates have declined in developed countries over the last 50 years. Today, we know that cigarette smoking is ...the major cause of preventable deaths due to tobacco smoke induced diseases. As a consequence of an increased awareness of smoking-related health risks, heated tobacco products (HTPs) are marketed as reduced toxicant alternatives to conventional tobacco products. Manufacturers claim that levels of toxicants and hazardous compounds are significantly reduced, implying that inhalation of the modified aerosol is less harmful compared to conventional cigarettes. In this manuscript, previous assessments of HTPs are briefly summarized, including a short discussion on challenges with the adaption of standard analytical methods used for tobacco smoke. The reliability of analytical data is important for risk assessment approaches that are based on reduced toxicant exposure. In order to assess a putative reduction of health risks, an integrated study design is required that should include clinical studies and epidemiology data. One manufacturer applied for a classification as a Modified Risk Tobacco Product (MRTP) in the United States, based on extensive toxicological studies that have also been published. However, data are not yet sufficient for a reliable assessment or recognition of putatively reduced health risks. Challenges regarding a classification in Europe are also discussed briefly in this review.
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