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1.
Part Fibre Toxicol ; 19(1): 32, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525968

RESUMO

The incorporation of nanomaterials (NMs) in consumer products has proven to be highly valuable in many sectors. Unfortunately, however, the same nano specific physicochemical properties, which make these material attractive, might also contribute to hazards for people exposed to these materials. The physicochemical properties of NMs will impact their interaction with biological surroundings and influence their fate and their potential adverse effects such as genotoxicity. Due to the large and expanding number of NMs produced, their availability in different nanoforms (NFs) and their utilization in various formats, it is impossible for risk assessment to be conducted on an individual NF basis. Alternative methods, such as grouping are needed for streamlining hazard assessment. The GRACIOUS Framework provides a logical and science evidenced approach to group similar NFs, allowing read-across of hazard information from source NFs (or non-NFs) with adequate hazard data to target NFs that lack such data. Here, we propose a simple three-tiered testing strategy to gather evidence to determine whether different NFs are sufficiently similar with respect to their potential to induce genotoxicity, in order to be grouped. The tiered testing strategy includes simple in vitro models as well as a number of alternative more complex multi-cellular in vitro models to allow for a better understanding of secondary NM-induced DNA damage, something that has been more appropriate in vivo until recently.


Assuntos
Nanoestruturas , Dano ao DNA , Humanos , Nanoestruturas/química , Nanoestruturas/toxicidade , Medição de Risco/métodos
2.
J Nanobiotechnology ; 20(1): 108, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248077

RESUMO

BACKGROUND: Two-dimensional ultrathin Ti3C2 (MXene) nanosheets have been extensively explored for various biomedical applications. However, safety issues and the effects of Ti3C2 on human health remain poorly understood. RESULTS: To explore the influence on foetal or offspring after exposure to Ti3C2 nanosheets, we established a mouse model exposed to different doses of Ti3C2 nanosheets during early pregnancy in this study. We found that Ti3C2 nanosheets had negligible effect on the reproductive ability of maternal mice, including average pregnancy days, number of new-borns, and neonatal weight, etc. Unexpectedly, abnormal neurobehavior and pathological changes in the cerebral hippocampus and cortex in adult offspring were observed following Ti3C2 nanosheet treatment. In further studies, it was found that Ti3C2 exposure led to developmental and functional defects in the placenta, including reduced area of labyrinth, disordered secretion of placental hormones, and metabolic function derailment. The long-chain unsaturated fatty acids were significantly higher in the placenta after Ti3C2 exposure, especially docosahexaenoic acid (DHA) and linoleic acid. The metabolic pathway analysis showed that biosynthesis of unsaturated fatty acids was upregulated while linoleic acid metabolism was downregulated. CONCLUSIONS: These developmental and functional defects, particularly metabolic function derailment in placenta may be the cause for the neuropathology in the offspring. This is the first report about the effects of Ti3C2 nanosheet exposure on pregnancy and offspring. The data provides a better understanding of Ti3C2 nanosheets safety. It is suggested that future studies should pay more attention to the long-term effects of nanomaterials exposure, including the health of offspring in adulthood, rather than only focus on short-term effects, such as pregnancy outcomes. Metabolomics could provide clues for finding the prevention targets of the biological negative effect of Ti3C2 nanosheets.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Animais , Feminino , Camundongos , Nanoestruturas/toxicidade , Placenta , Gravidez , Titânio/toxicidade
3.
Bioresour Technol ; 351: 127048, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35337989

RESUMO

Vast improvements in nanotechnology have led to the wide usage of nanomaterials (NMs) in daily products. This study reviews the interactions between NMs and microalgae in terms of impacts on growth and photosynthetic efficiency, and their toxicity on microalgae. All types of NMs such as carbon-based NMs (CNMs), metal oxide-based NMs (MONMs) and noble metal-based NMs (NMNMs) improve microalgal growth and photosynthetic efficiency at low concentration, typically ranging between 1 and 15 mg/L depending on the type of NMs, due to hormetic responses by microalgae. Higher concentrations of NMs have been found to reduce photosynthetic efficiency and subsequent growth inhibition of microalgae. MONMs-microalgae and NMNMs-microalgae interactions focus on membrane alteration, whereas carbon-based NMs-microalgae focus more on shading effect. The toxicity of each type of NMs on microalgae is in the order rGO > GO > MG > CNT for carbon-based NMs, ZnO > TiO2 > CuO > Fe2O3 for MONMs and Ag > Au > Pt for NMNMs. Incorporation of NMs in microalgae are seen to have promising future on producing higher microalgae yield with increased economic efficiency.


Assuntos
Microalgas , Nanoestruturas , Carbono/farmacologia , Nanoestruturas/toxicidade , Óxidos , Fotossíntese
4.
Langmuir ; 38(11): 3434-3445, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35274959

RESUMO

Peptide-based hydrogels have attracted much attention due to their extraordinary applications in biomedicine and offer an excellent mimic for the 3D microenvironment of the extracellular matrix. These hydrated matrices comprise fibrous networks held together by a delicate balance of intermolecular forces. Here, we investigate the hydrogelation behavior of a designed decapeptide containing a tetraleucine self-assembling backbone and fibronectin-related tripeptides near both ends of the strand. We have observed that this synthetic peptide can produce hydrogel matrices entrapping >99% wt/vol % water. Ultrastructural analyses combining atomic force microscopy, small-angle neutron scattering, and X-ray diffraction revealed that amyloid-like fibrils form cross-linked networks endowed with remarkable thermal stability, the structure of which is not disrupted up to temperatures >80 °C. We also examined the interaction of peptide hydrogels with either NIH3T3 mouse fibroblasts or HeLa cells and discovered that the matrices sustain cell viability and induce morphogenesis into grape-like cell spheroids. The results presented here show that this decapeptide is a remarkable building block to prepare highly stable scaffolds simultaneously endowed with high water retention capacity and the ability to instruct cell growth into tumor-like spheroids even in noncarcinoma lineages.


Assuntos
Hidrogéis , Nanoestruturas , Amiloide , Animais , Células HeLa , Humanos , Hidrogéis/química , Camundongos , Morfogênese , Células NIH 3T3 , Nanoestruturas/toxicidade , Peptídeos/química , Água
5.
Langmuir ; 38(12): 3765-3774, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35302783

RESUMO

We demonstrate a facile method to fabricate a recyclable cell-alignment scaffold using nanogrooves based on sublimable liquid crystal (LC) material. Randomly and uniaxially arranged smectic LC structures are obtained, followed by sublimation and recondensation processes, which directly produce periodic nanogrooves with dimensions of a couple of hundreds of nanometers. After treatment with osmium tetroxide (OsO4), the nanogroove can serve as a scaffold to efficiently induce directed cell growth without causing cytotoxicity, and it can be used repeatedly. Together, various cell types are applied to the nanogroove, proving the scaffold's broad applicability. Depending on the nanotopography of the LC structures, cells exhibit different morphologies and gene expression patterns, compared to cells on standard glass substrates, according to microscopic observation and qPCR. Furthermore, cell sheets can be formed, which consist of oriented cells that can be repeatedly formed and transferred to other substrates, while maintaining its organization. We believe that our cell-aligning scaffold may pave the way for the soft material field to bioengineering, which can involve fundamentals in cell behavior and function, as well as applications for regenerative medicine.


Assuntos
Cristais Líquidos , Nanoestruturas , Cristais Líquidos/química , Nanoestruturas/toxicidade , Tetróxido de Ósmio
6.
Part Fibre Toxicol ; 19(1): 23, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35337343

RESUMO

BACKGROUND: There is an increasing concern about the neurotoxicity of engineered nanomaterials (NMs). To investigate the effects of subchronic oral exposures to SiO2 and CeO2 NMs on Alzheimer's disease (AD)-like pathology, 5xFAD transgenic mice and their C57BL/6J littermates were fed ad libitum for 3 or 14 weeks with control food pellets, or pellets dosed with these respective NMs at 0.1% or 1% (w/w). Behaviour effects were evaluated by X-maze, string suspension, balance beam and open field tests. Brains were analysed for plaque load, beta-amyloid peptide levels, markers of oxidative stress and neuroinflammation. RESULTS: No marked behavioural impairments were observed in the mice exposed to SiO2 or CeO2 and neither treatment resulted in accelerated plaque formation, increased oxidative stress or inflammation. In contrast, the 5xFAD mice exposed to 1% CeO2 for 14 weeks showed significantly lower hippocampal Aß plaque load and improved locomotor activity compared to the corresponding controls. CONCLUSIONS: The findings from the present study suggest that long-term oral exposure to SiO2 or CeO2 NMs has no neurotoxic and AD-promoting effects. The reduced plaque burden observed in the mice following dietary CeO2 exposure warrants further investigation to establish the underlying mechanism, given the easy applicability of this administration method.


Assuntos
Doença de Alzheimer , Nanoestruturas , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Exposição Dietética , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nanoestruturas/toxicidade , Placa Amiloide/induzido quimicamente , Dióxido de Silício/toxicidade
7.
Ecotoxicology ; 31(3): 524-535, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35262834

RESUMO

The increasing use of antibacterial silver nanomaterials (AgNM) in consumer products leads to their release into sewers. High amounts of AgNM become retained in sewage sludge, which causes their accumulation in agricultural soils when sewage sludge is applied as fertilizer. This increase in AgNM arouses concerns about toxicity to soil organisms and transfer within trophic levels. Long-term field studies simulating the sewage sludge pathway to soils are sparse, and the effects of a second sewage sludge application are unknown. In this perennial field lysimeter study, a twofold application of AgNM (NM-300K, 2 + 3 mg AgNM/kg dry matter soil (DMS)) and a onefold application of silver nitrate (AgNO3, 2 mg Ag/kg DMS) by sewage sludge to the uppermost 20 cm of the soil (Cambisol) were applied. The response of microorganisms to the applications was determined by measuring the inhibition of ammonium-oxidizing bacteria (AOB). Silver concentration in soil, leachates, and crops were measured after acid digestion by inductively coupled plasma mass spectrometry (ICP-MS). Almost no vertical Ag translocation to deeper soil layers and negligible Ag release to leachates suggest that soil is a large sink for AgNM and AgNO3. For AgNM, an increase in toxicity to AOB was shown after the second sewage sludge application. The application of AgNO3 resulted in long-term toxicity comparable to the toxicity of AgNM. Low root uptake from both AgNM- and AgNO3-spiked lysimeters to crops indicates their incomplete immobilization, which is why food chain uptake cannot completely be excluded. However, the root-shoot barrier for wheat (9.8 → 0.1 mg/kg) and skin body barrier for sugar beets (1.0 → 0.2 mg/kg) will further reduce the accumulation within trophic levels. Moreover, the applied AgNM concentration was above the predicted environmental concentration, which is why the root uptake might be negligible in agricultural practice.


Assuntos
Nanoestruturas , Poluentes do Solo , Fertilizantes/análise , Nanoestruturas/toxicidade , Esgotos/química , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
8.
Regul Toxicol Pharmacol ; 131: 105156, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35321839

RESUMO

In recent years, various ecotoxicological test guidelines and (technical) guidance documents have been evaluated and updated with regard to their applicability to nanomaterials (NMs). Several of these have currently reached official regulatory status. Ensuring their harmonized implementation with previously recognized methods for ecotoxicity testing of chemicals is a crucial next step towards effective and efficient regulation of NMs. In the present study, we evaluated the feasibility of assessing multigenerational effects in the first generation of offspring derived from exposed Daphnia magna whilst maintaining test conditions in accordance with regulatory test guidelines and guidance documents for NMs. To do so, we integrated the recommendations for ecotoxicological testing of NMs as defined in OECD Guidance Document 317 into an extended long-term D. magna reproduction test method (OECD Test Guideline 211) and assessed effects of two poorly soluble NMs (nTiO2 and nCeO2). Our results show adverse effects on life-history parameters of D. magna exposed to the selected nanomaterials within the range of reported environmental concentrations. We argue that conforming to OECD test guidelines and accompanying guidance for nanomaterials is feasible when performing D. magna reproduction tests and can minimize unnecessary duplication of similar experiments, even when extensions to the standardized test setup are added.


Assuntos
Nanoestruturas , Poluentes Químicos da Água , Animais , Daphnia , Ecotoxicologia/métodos , Nanoestruturas/toxicidade , Reprodução , Poluentes Químicos da Água/toxicidade
9.
Nanotoxicology ; 16(1): 114-134, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35343373

RESUMO

Exposure to engineered nanomaterials (ENM) poses a potential health risk to humans through long-term, repetitive low-dose exposures. Currently, this is not commonplace within in vitro lung cell cultures. Therefore, the purpose of this study was to consider the optimal exposure approach toward determining the stability, sensitivity and validity of using in vitro lung cell mono- and co-cultures to determine ENM hazard. A range of exposure scenarios were conducted with DQ12 (previously established as a positive particle control) (historic and re-activated), TiO2 (JRC NM-105) and BaSO4 (JRC NM-220) on both monocultures of A549 cells as well as co-cultures of A549 cells and differentiated THP-1 cells. Cell cultures were exposed to either a single, or a repeated exposure over 24, 48- or 72-hours at in vivo extrapolated concentrations of 0-5.2 µg/cm2, 0-6 µg/cm2 and 0-1µg/cm2. The focus of this study was the pro-inflammatory, cytotoxic and genotoxic response elicited by these ENMs. Exposure to DQ12 caused pro-inflammatory responses after 48 hours repeat exposures, as well as increases in micronucleus frequency. Neither TiO2 nor BaSO4 elicited a pro-inflammatory response at this time point. However, there was induction of IL-6 after 24 hours TiO2 exposure. In conclusion, it is important to consider the appropriateness of the positive control implemented, the cell culture model, the time of exposure as well as the type of exposure (bolus or fractionated) before establishing if an in vitro model is appropriate to determine the level of response to the specific ENM of interest.


Assuntos
Nanoestruturas , Técnicas de Cocultura , Dano ao DNA , Humanos , Pulmão , Nanoestruturas/toxicidade , Células THP-1
10.
J Hazard Mater ; 429: 128361, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35236038

RESUMO

Two-dimensional transition metal dichalcogenide (TMDC) nanomaterials have attracted tremendous research interest in various fields, but the effects of eco-corona formation on the transformation mechanisms and ecological risk of TMDCs remain largely unknown. The effect of eco-corona formation on TMDC reactivity was explored using extracellular polymeric substances (EPS) as the eco-corona constituents and single-layer molybdenum disulfide (SLMoS2) as the model TMDC. We found that EPS promoted lattice distortion and the formation of defects (sulfur vacancies and pores) on SLMoS2 after it was aged (precoated) with EPS under simulated visible-light irradiation. In addition, the EPS-corona induced higher free radical (especially hyperoxide radical) photogeneration by SLMoS2. Furthermore, compared to pristine SLMoS2, SLMoS2-EPS exhibited stronger developmental inhibition, oxidative stress, membrane damage, photosynthetic toxicity and metabolic perturbation effects on Chlorella vulgaris. However, the endocytosis pathway (especially macropinocytosis) of SLMoS2 entry into C. vulgaris was inhibited by EPS. Metabolic and transcriptomic analyses revealed that the enhanced toxicity of SLMoS2-EPS was associated with the downregulation of fatty acid metabolism and transcription related to photosynthesis, respectively. The present work provides mechanistic insights into the roles of the EPS-corona on the environmental transformation and phytotoxicity of TMDCs, which benefit environmental safety assessments and sustainable applications of engineered nanomaterials.


Assuntos
Chlorella vulgaris , Nanoestruturas , Matriz Extracelular de Substâncias Poliméricas , Luz , Molibdênio/toxicidade , Nanoestruturas/toxicidade
11.
J Am Chem Soc ; 144(12): 5503-5516, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35235326

RESUMO

Biological nanomachines, including proteins and nucleic acids whose function is activated by conformational changes, are involved in every biological process, in which their dynamic and responsive behaviors are controlled by supramolecular recognition. The development of artificial nanomachines that mimic the biological functions for potential application as therapeutics is emerging; however, it is still limited to the lower hierarchical level of the molecular components. In this work, we report a synthetic machinery nanostructure in which actuatable molecular components are integrated into a hierarchical nanomaterial in response to external stimuli to regulate biological functions. Two nanometers core-sized gold nanoparticles are covered with ligand layers as actuatable components, whose folding/unfolding motional response to the cellular environment enables the direct penetration of the nanoparticles across the cellular membrane to disrupt intracellular organelles. Furthermore, the pH-responsive conformational movements of the molecular components can induce the apoptosis of cancer cells. This strategy based on the mechanical motion of molecular components on a hierarchical nanocluster would be useful to design biomimetic nanotoxins.


Assuntos
Fenômenos Biológicos , Nanopartículas Metálicas , Nanoestruturas , Membrana Celular , Ouro , Nanoestruturas/toxicidade
12.
Einstein (Sao Paulo) ; 20: eRB5898, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35195162

RESUMO

The delivery of nucleic acids to cells is considered a crucial step for the success of genetic modifications aimed at therapeutic purposes or production of genetically modified animals. In this context, nanotechnology is one of the most promising fields of science, with the potential to solve several existing problems. Nanostructures have desirable characteristics to be used as carriers, such as nanometric size, large surface area, cell internalization capacity, prolonged and controlled release, among others. Genetically modified animals can contribute to the production of biopharmaceuticals, through the expression of high-associated-value molecules. The production of these animals, also known as biofactories, further enhances Brazilian agribusiness, since it allows adding value to the final product, and favors the integration between the agricultural market and the pharmaceutical sector. However, there is a growing concern about the safety and possible harmful effects of nanostructures, since data on the safe use of these materials are still insufficient. The objective of this review was to address aspects of the use of nanostructures, mainly carbon nanotubes as nucleic acid carriers, aiming at the production of genetically modified animals, with the certainty that progress in this field of knowledge depends on more information on the mechanisms of interaction between nanostructures, cells and embryos, as well as on its toxicity.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Ácidos Nucleicos , Animais , Sistemas de Liberação de Medicamentos , Nanoestruturas/química , Nanoestruturas/toxicidade , Nanotecnologia
13.
Ecotoxicol Environ Saf ; 232: 113249, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35104779

RESUMO

Purification and detection of algal toxins is the most effective technique to ensure that people have clean and safe drinking water. To achieve these objectives, various state-of-the-art technologies were designed and fabricated to decontaminate and detect algal toxins in aquatic environments. Amongst these technologies, aptamer-functionalized hybrid nanomaterials conjugates have received significant consideration as a result of their several benefits over other methods, such as good controllable selectivity, low immunogenicity, and biocompatibility. Because of their excellent properties, aptamer-functionalized hybrid nanomaterials conjugates are one of several remarkable agents. Several isolated aptamer sequences for algal toxins are addressed in this review, as well as aptasensor and decontamination aptamer functionalized metal nanoparticle-derived hybrid nanocomposites applications. In addition, we present diverse aptamer-functionalized hybrid nanomaterial conjugates designs and their applications for sensing and decontamination.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanoestruturas , Descontaminação , Humanos , Nanoestruturas/toxicidade
14.
Adv Exp Med Biol ; 1351: 23-39, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35175610

RESUMO

Graphene family nanomaterials (GFNs) are well-known carbonaceous materials, which find application in several fields like optoelectronics, photocatalysis, nanomedicine, and tissue regeneration. Despite possessing many advantages in biomedical applications, GFNs exhibited toxicity depending on various parameters including dosage, size, exposure time, and kinds of administration. GFNS are majorly classified into nanosheets, quantum dots, nanoplatelets, and nanoribbons based on morphology. Understanding the toxic effects of GFNs would provide new suggestions as to how the materials can be utilized effectively. Hence, we are summarizing here some of the recent findings in cellular and animal level toxicity studies of GFNs on the perspective of their different morphologies. Notwithstanding, we highlight progress, challenges, and new toxicological approaches to ensure biosafety of GFNs for future directions.


Assuntos
Grafite , Nanoestruturas , Animais , Grafite/toxicidade , Nanomedicina , Nanoestruturas/toxicidade
15.
ACS Appl Mater Interfaces ; 14(5): 6404-6416, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35077153

RESUMO

In situ oxygen generation is the most common strategy to boost reactive oxygen species (ROS) for enhancing the efficacy of phototherapy in cancer, including photodynamic therapy (PDT) and photothermal therapy (PTT). However, hyperoxidation or hyperthermia often triggers stress-defense pathways and promotes tumor cell survival, thus severely limiting the therapeutic efficacy. To overcome the tumor hypoxia and thermal resistance existing in phototherapy, we constructed a self-synergistic nanoplatform for tumors by incorporating brusatol, a nuclear factor erythroid 2-related factor (Nrf2) inhibitor, into the silica nanonetwork. It was then sequentially decorated with MnO2 and the photosensitizer chlorin e6 (Ce6) and then coated with poly(ethylene glycol)-folate (PEG-FA)-functionalized polydopamine (PDA) (designated as brusatol/silica@MnO2/Ce6@PDA-PEG-FA). As an oxygen generator, MnO2 can promote ROS production, which not only directly enhances Ce6-mediated PDT but also strengthens PDA-mediated PTT by attacking heat shock proteins (HSPs). Particularly, brusatol could efficiently inhibit the activation of Nrf2 defense pathway under hyperoxidation and hyperthermia and cause glutathione peroxidase 4 (GPX4) and ferritin heavy chain (FTH) inactivation, thereby inducing ferroptosis and ultimately enhancing the phototherapeutic effects. By exploiting these features, brusatol/silica@MnO2/Ce6@PDA-PEG-FA exhibited excellent antitumor efficacy with enhanced PDT and PTT both in in vitro and in vivo studies. Overall, our work highlights a promising strategy against hypoxia- and hyperthermia-associated resistance in phototherapy via suppressing stress-defense system and inducing ferroptosis.


Assuntos
Ferroptose , Fator 2 Relacionado a NF-E2/metabolismo , Nanoestruturas/química , Fototerapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Clorofilídeos/química , Clorofilídeos/farmacologia , Clorofilídeos/uso terapêutico , Ferroptose/efeitos dos fármacos , Ácido Fólico/análogos & derivados , Ácido Fólico/química , Humanos , Hipertermia Induzida , Indóis/química , Raios Infravermelhos , Compostos de Manganês/química , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Óxidos/química , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Polietilenoglicóis/química , Polímeros/química , Quassinas/química , Dióxido de Silício/química
16.
ACS Appl Mater Interfaces ; 14(5): 6370-6386, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35090345

RESUMO

Drug-resistant capacity in a small population of tumor-initiating cancer stem cells (tiCSCs) can be due to aberrant epigenetic changes. However, currently available conventional detection methods are inappropriate and cannot be applied to investigate the scarce population (tiCSCs). In addition, selective inhibitor drugs are shown to reverse epigenetic changes; however, each cancer type is discrete. Hence, it is essential to probe the resultant changes in tiCSCs even after therapy. Therefore, we have developed a multimode nanoplatform to investigate tiCSCs, detect epigenetic changes, and subsequently explore their transformation signals following drug therapy. We performed this by developing a surface-enhanced Raman scattering (SERS)-active nanoplatform integrated with n-dopant using an ultrafast laser ionization technique. The dopant functionalization enhances Raman scattering ability and permits label-free analysis of biomarkers in tiCSCs with the resolution down to the cellular level. Here, we investigated epigenetic biomarkers of tiCSCs in pancreatic and lung cancers. An extended study using inhibitor drugs demonstrates an unexpected increase of tiCSCs from lung cancer; this difference can be attributed to transformation changes in lung tiCSC. Thus, our work brings new insight into the differentiation abilities of CSCs upon epigenetic reversal, emphasizing unique perceptions in cancer treatment.


Assuntos
Nanoestruturas/química , Células-Tronco Neoplásicas/metabolismo , Biomarcadores Tumorais/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Decitabina/química , Decitabina/farmacologia , Epigênese Genética , Humanos , Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/farmacologia , Lasers , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Nanoestruturas/toxicidade , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fósforo/química , Silício/química , Análise Espectral Raman
17.
Mar Pollut Bull ; 174: 113276, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35090270

RESUMO

A wide range of contaminants of emerging concern such as micro/nanoplastics (MPs/PNPs) and metal-nanoparticles (Me-NPs) from anthropogenic activities have been identified in aquatic environments. The hazardous effects of these micro/nanomaterials as pollutants in organisms and the lack of knowledge about their behavior in aquatic environments have generated growing concern in the scientific community. The nanomaterials have a colloidal-type behavior due to their size range but with differences in their physicochemical properties. This review comprises the behavior of micro/nanomaterials pollutants and the physicochemical interactions between MPs/PNPs and Me-NPs in aquatic environments, and their potential toxicological effects in organisms. Moreover, this article describes the potential use of Me-NPs to remove MPs/PNPs present in the water column due to their photocatalytic and magnetic properties. It also discusses the challenge to determine harmful effects of micro/nanomaterials pollutants in organisms and provides future research directions to improve integrated management strategies to mitigate their environmental impact.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Nanoestruturas , Poluentes Químicos da Água , Nanopartículas Metálicas/toxicidade , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade
18.
ACS Nano ; 16(2): 2249-2260, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35048688

RESUMO

Mitochondria and chloroplasts not only are cellular energy sources but also have important regulatory and developmental roles in cell function. CeO2, FeOx ENMs, ZnS, CdS QDs, and relative metal salts were utilized in Murashige-Skoog (MS) synthetic growth medium at different concentrations (80-500 mg L-1) and times of exposures (0-20 days). Analysis of physiological and molecular response of A. thaliana chloroplasts and mitochondrion demonstrates that ENMs increase or decrease functionality and organelle genome replication. Exposure to nanoscale CeO2 and FeOx causes an 81-105% increase in biomass, whereas ZnS and CdS QDs yielded neutral or a 59% decrease in growth, respectively. Differential effects between ENMs and their corresponding metal salts highlight nanoscale-specific response pathways, which include energy production and oxidative stress response. Differences may be ascribed to ENM and the metal salt dissolution rate and the toxicity of the metal ion, which suggests eventual biotransformation processes occurring within the plant. With regard to specific effects on plastid (pt) and mitochondrial (mt) DNA, CdS QD exposure triggered potential variations at the substoichiometric level in the two organellar genomes, while nanoscale FeOx and ZnS QDs caused a 1- to 3-fold increase in ptDNA and mtDNA copy numbers. Nanoparticle CeO2 exposure did not affect ptDNA and mtDNA stoichiometry. These findings suggest that modification in stoichiometry is a potential morpho-functional adaptive response to ENM exposure, triggered by modifications of bioenergetic redox balance, which leads to reducing the photosynthesis or cellular respiration rate.


Assuntos
Arabidopsis , Nanoestruturas , Arabidopsis/genética , Cloroplastos/metabolismo , Mitocôndrias/genética , Nanoestruturas/toxicidade , Plastídeos/genética , Plastídeos/metabolismo
19.
Nanotechnology ; 33(20)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35090149

RESUMO

In recent years, nanozymes based on two-dimensional (2D) nanomaterials have been receiving great interest for cancer photothermal therapy. 2D materials decorated with nanoparticles (NPs) on their surface are advantageous over conventional NPs and 2D material based systems because of their ability to synergistically improve the unique properties of both NPs and 2D materials. In this work, we report a nanozyme based on flower-like MoS2nanoflakes (NFs) by decorating their flower petals with NCeO2using polyethylenimine (PEI) as a linker molecule. A detailed investigation on toxicity, biocompatibility and degradation behavior of fabricated nanozymes in wild-typeDrosophila melanogastermodel revealed that there were no significant effects on the larval size, morphology, larval length, breadth and no time delay in changing larvae to the third instar stage at 7-10 d for MoS2NFs before and after NCeO2decoration. The muscle contraction and locomotion behavior of third instar larvae exhibited high distance coverage for NCeO2decorated MoS2NFs when compared to bare MoS2NFs and control groups. Notably, the MoS2and NCeO2-PEI-MoS2NFs treated groups at 100µg ml-1covered a distance of 38.2 mm (19.4% increase when compared with control) and 49.88 mm (no change when compared with control), respectively. High-resolution transmission electron microscopy investigations on the new born fly gut showed that the NCeO2decoration improved the degradation rate of MoS2NFs. Hence, nanozymes reported here have huge potential in various fields ranging from biosensing, cancer therapy and theranostics to tissue engineering and the treatment of Alzheimer's disease and retinal therapy.


Assuntos
Materiais Biocompatíveis/toxicidade , Cério/toxicidade , Dissulfetos/toxicidade , Molibdênio/toxicidade , Nanoestruturas/toxicidade , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacocinética , Cério/administração & dosagem , Cério/química , Cério/farmacocinética , Dissulfetos/administração & dosagem , Dissulfetos/química , Dissulfetos/farmacocinética , Drosophila melanogaster , Trato Gastrointestinal/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Locomoção/efeitos dos fármacos , Teste de Materiais , Taxa de Depuração Metabólica , Molibdênio/administração & dosagem , Molibdênio/química , Molibdênio/farmacocinética , Contração Muscular/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Polietilenoimina/administração & dosagem , Polietilenoimina/química , Polietilenoimina/farmacocinética , Polietilenoimina/toxicidade , Espécies Reativas de Oxigênio/metabolismo
20.
Environ Sci Pollut Res Int ; 29(23): 35217-35229, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35048350

RESUMO

Polyaniline nanorods (PANRs) are typical one-dimensional nanomaterials (1D NMs), which are widely used in medicine, batteries and water treatment, etc. Applications of PANRs will eventually enter the soil environment, but their ecotoxicity has been barely reported. Therefore, we measured earthworm biomass, earthworm biomarkers and soil enzymes to investigate the ecotoxicity of PANRs. The result of positive and increasing growth inhibition rates (GIR) showed that PANRs inhibited earthworm growth. As for earthworm biomarkers, PANRs caused a decrease in protein content, indicating that PANRs stress would increase earthworm energy consumption. Except for the 7th day, the activities of SOD, CAT and POD consistently increased, suggesting that PANRs activated the earthworm antioxidant system. The continually augment of MDA content indicated that PANRs stress would cause earthworm lipid damage. Na+-K+-ATPase increased with an excellent dose-time relationship. Differently, cellulase and AChE activities promoted at low concentrations and inhibited at high concentrations. The positive and dose-dependent IBRv2 indicated that the higher the concentrations of PANRs, the greater the ecotoxicity to earthworms. PANRs inhibited the soil enzyme activities such as sucrase, neutral phosphatase, protease and urease, while induced catalase activity in a dose-dependent manner. Earthworm addition reduced catalase activity by 10.74-29.99%, but improved other soil enzymes activities, demonstrating that earthworms played a positive role in regulating soil enzyme activity. GMean and T-SQI consistently increased due to earthworm activity, meaning a higher soil microbial functional diversity. Generally, this study provided data support for future PANRs toxicity studies, but their toxicity mechanisms still need to be further studied.


Assuntos
Nanoestruturas , Nanotubos , Oligoquetos , Poluentes do Solo , Compostos de Anilina , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Malondialdeído/metabolismo , Nanoestruturas/toxicidade , Solo , Poluentes do Solo/análise , Superóxido Dismutase/metabolismo
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