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1.
Front Aging Neurosci ; 16: 1453710, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39267721

RESUMO

Aging encompasses a wide array of detrimental effects that compromise physiological functions, elevate the risk of chronic diseases, and impair cognitive abilities. However, the precise underlying mechanisms, particularly the involvement of specific molecular regulatory proteins in the aging process, remain insufficiently understood. Emerging evidence indicates that c-Jun N-terminal kinase (JNK) serves as a potential regulator within the intricate molecular clock governing aging-related processes. JNK demonstrates the ability to diminish telomerase reverse transcriptase activity, elevate ß-galactosidase activity, and induce telomere shortening, thereby contributing to immune system aging. Moreover, the circadian rhythm protein is implicated in JNK-mediated aging. Through this comprehensive review, we meticulously elucidate the intricate regulatory mechanisms orchestrated by JNK signaling in aging processes, offering unprecedented molecular insights with significant implications and highlighting potential therapeutic targets. We also explore the translational impact of targeting JNK signaling for interventions aimed at extending healthspan and promoting longevity.

2.
Food Chem ; 460(Pt 2): 140548, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39096799

RESUMO

Electrochemical sensors and electroanalytical techniques become emerging as effective and low-cost tools for rapid assessment of special parameters of the food quality. Chemically modified electrodes are developed to change properties and behaviour, particularly sensitivity and selectivity, of conventional electroanalytical sensors. Within this comprehensive review, novel trends in chemical modifiers material structure, electrodes construction and flow analysis platforms are described and evaluated. Numerous recent application examples for the detection of food specific analytes are presented in a form of table to stimulate further development in both, the basic research and commercial field.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Análise de Alimentos , Contaminação de Alimentos , Análise de Alimentos/instrumentação , Técnicas Eletroquímicas/instrumentação , Contaminação de Alimentos/análise
3.
Chemosphere ; 364: 142988, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39103097

RESUMO

Increased awareness of the impact of human activities on the environment has emerged in recent decades. One significant global environmental and human health issue is the development of materials that could potentially have negative effects. These materials can accumulate in the environment, infiltrate organisms, and move up the food chain, causing toxic effects at various levels. Therefore, it is crucial to assess materials comprising nano-scale particles due to the rapid expansion of nanotechnology. The aquatic environment, particularly vulnerable to waste pollution, demands attention. This review provides an overview of the behavior and fate of metallic nanoparticles (NPs) in the aquatic environment. It focuses on recent studies investigating the toxicity of different metallic NPs on aquatic organisms, with a specific emphasis on thiol-biomarkers of oxidative stress such as glutathione, thiol- and related-enzymes, and metallothionein. Additionally, the selection of suitable measurement methods for monitoring thiol-biomarkers in NPs' ecotoxicity assessments is discussed. The review also describes the analytical techniques employed for determining levels of oxidative stress biomarkers.

4.
Biosens Bioelectron ; 262: 116545, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38971040

RESUMO

Determination of plasma uracil was reported as a method for evaluation of Dihydropyrimidine dehydrogenase (DPD) activity that is highly demanded to ensure the safe administration of 5-fluorouracil (5-FU)-based therapies to cancer patients. This work reports the development of a simple electroanalytical method based on adsorptive stripping square wave voltammetry (AdSWV) at mercury film-coated glassy carbon electrode (MF/GCE) for the highly sensitive determination of uracil in biological fluids that can be used for diagnosis of decreased DPD activity. Due to the formation of the HgII-Uracil complex at the electrode surface, the accuracy of the measurement was not affected by the complicated matrices in biological fluids including human serum, plasma, and urine. The high sensitivity of the developed method results in a low limit of detection (≈1.3 nM) in human plasma samples, falling below the practical cut-off level of 15 ng mL-1 (≈0.14 µM). This threshold concentration is crucial for predicting 5-FU toxicity, as reported in buffer, and ≤1.15% in biological samples), and accuracy (recovery percentage close to 100%).


Assuntos
Técnicas Biossensoriais , Deficiência da Di-Hidropirimidina Desidrogenase , Eletrodos , Fluoruracila , Mercúrio , Uracila , Humanos , Uracila/sangue , Mercúrio/sangue , Limite de Detecção , Técnicas Eletroquímicas/métodos , Di-Hidrouracila Desidrogenase (NADP)/metabolismo
5.
Adv Colloid Interface Sci ; 331: 103233, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38924801

RESUMO

A substantial development in nanoscale materials possessing catalytic activities comparable with natural enzymes has been accomplished. Their advantages were owing to the excellent sturdiness in an extreme environment, possibilities of their large-scale production resulting in higher profitability, and easy manipulation for modification. Despite these advantages, the main challenge for artificial enzyme mimetics is the lack of substrate selectivity where natural enzymes flourish. This review addresses this vital problem by introducing substrate selectivity strategies to three classes of artificial enzymes: molecularly imprinted polymers, nanozymes (NZs), and DNAzymes. These rationally designed strategies enhance the substrate selectivity and are discussed and exemplified throughout the review. Various functional mechanisms associated with applying enzyme mimetics in biosensing and bioassays are also given. Eventually, future directives toward enhancing the substrate selectivity of biomimetics and related challenges are discussed and evaluated based on their efficiency and convenience in biosensing and bioassays.


Assuntos
Bioensaio , Materiais Biomiméticos , Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Materiais Biomiméticos/química , Especificidade por Substrato , DNA Catalítico/química , DNA Catalítico/metabolismo , Enzimas/metabolismo , Enzimas/química , Polímeros Molecularmente Impressos/química , Humanos
6.
Food Chem ; 452: 139434, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38733680

RESUMO

Arthrospira (Limnospira) maxima (A. maxima) and Chlorella vulgaris (Ch. vulgaris) are among the approved microalgae and cyanobacteria (MaC) in the food industry that are known to be safe for consumption. However, both organisms are controversial regarding their vitamin B12 content, due to the possible occurrence of pseudo-cobalamin. Concurrently, their nutrition profiles remain understudied. The main purpose of the present study was to identify their nutrition profiles, focusing mainly on vitamin B12, amino acids, and micronutrients under iron-induced hormesis (10 mg/L Fe in treated samples). Our findings indicate a higher B12 content in A. maxima compared to Ch. vulgaris (both control and treated samples). Using liquid chromatography with tandem mass spectrometry (LC-MS/MS), the cyanocobalamin content was determined as 0.42 ± 0.09 µg/g dried weight (DW) in the A. maxima control and 0.55 ± 0.02 µg/g DW in treated A. maxima, resulting in an insignificant difference. In addition, the iron-enriched medium increased the amount of iron in both tested biomasses (p < 0.01). However, a more pronounced (approximately 100×) boost was observed in Ch. vulgaris, indicating a better absorption capacity (control Ch. vulgaris 0.16 ± 0.01 mg/g Fe, treated Ch. vulgaris 15.40 ± 0.34 mg/g Fe). Additionally, Ch. vulgaris also showed a higher micronutrient content. Using both tested microalgae, meeting the sufficient recommended daily mineral allowance for an adult is possible. By combining biomass from A. maxima and Ch. vulgaris in a ratio of 6:1, we can fulfill the recommended daily allowance of vitamin B12 and iron by consuming 6 tablets/6 g. Importantly, iron hormesis stimulated amino acid composition in both organisms. The profile of amino acids may suggest these biomasses as promising potential nutrition sources.


Assuntos
Aminoácidos , Chlorella vulgaris , Micronutrientes , Spirulina , Vitamina B 12 , Chlorella vulgaris/química , Chlorella vulgaris/metabolismo , Chlorella vulgaris/crescimento & desenvolvimento , Vitamina B 12/metabolismo , Vitamina B 12/análise , Micronutrientes/análise , Micronutrientes/metabolismo , Aminoácidos/metabolismo , Aminoácidos/análise , Spirulina/química , Spirulina/metabolismo , Valor Nutritivo , Microalgas/química , Microalgas/metabolismo , Microalgas/crescimento & desenvolvimento , Espectrometria de Massas em Tandem , Ferro/metabolismo , Ferro/análise
7.
Arch Toxicol ; 98(8): 2393-2408, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38744709

RESUMO

Increasing evidence has revealed that cellular senescence drives NDs, including Alzheimer's disease (AD) and Parkinson's disease. Different senescent cell populations secrete senescence-associated secretory phenotypes (SASP), including matrix metalloproteinase-3, interleukin (IL)-1α, IL-6, and IL-8, which can harm adjacent microglia. Moreover, these cells possess high expression levels of senescence hallmarks (p16 and p21) and elevated senescence-associated ß-galactosidase activity in in vitro and in vivo ND models. These senescence phenotypes contribute to the deposition of ß-amyloid and tau-protein tangles. Selective clearance of senescent cells and SASP regulation by inhibiting p38/mitogen-activated protein kinase and nuclear factor kappa B signaling attenuate ß-amyloid load and prevent tau-protein tangle deposition, thereby improving cognitive performance in AD mouse models. In addition, telomere shortening, a cellular senescence biomarker, is associated with increased ND risks. Telomere dysfunction causes cellular senescence, stimulating IL-6, tumor necrosis factor-α, and IL-1ß secretions. The forced expression of telomerase activators prevents cellular senescence, yielding considerable neuroprotective effects. This review elucidates the mechanism of cellular senescence in ND pathogenesis, suggesting strategies to eliminate or restore senescent cells to a normal phenotype for treating such diseases.


Assuntos
Senescência Celular , Doenças Neurodegenerativas , Humanos , Senescência Celular/efeitos dos fármacos , Animais , Fenótipo Secretor Associado à Senescência , Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Doença de Parkinson/metabolismo , Encurtamento do Telômero/efeitos dos fármacos , Transdução de Sinais
8.
J Control Release ; 371: 338-350, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38789089

RESUMO

Nutrient or energy deprivation, especially glucose restriction, is a promising anticancer therapeutic approach. However, establishing a precise and potent deprivation strategy remains a formidable task. The Golgi morphology is crucial in maintaining the function of transport proteins (such as GLUT1) driving glycolysis. Thus, in this study, we present a "Golgi-customized Trojan horse" based on tellurium loaded with apigenin (4',5,7-trihydroxyflavone) and human serum albumin, which was able to induce GLUT1 plasma membrane localization disturbance via Golgi dispersal leading to the inhibition of tumor glycolysis. Diamond-shaped delivery system can efficiently penetrate into cells as a gift like Trojan horse, which decomposes into tellurite induced by intrinsically high H2O2 and GSH levels. Consequently, tellurite acts as released warriors causing up to 3.8-fold increase in Golgi apparatus area due to the down-regulation of GOLPH3. Further, this affects GLUT1 membrane localization and glucose transport disturbance. Simultaneously, apigenin hinders ongoing glycolysis and causes significant decrease in ATP level. Collectively, our "Golgi-customized Trojan horse" demonstrates a potent antitumor activity because of its capability to deprive energy resources of cancer cells. This study not only expands the applications of tellurium-based nanomaterials in the biomedicine but also provides insights into glycolysis restriction for anticancer therapy.


Assuntos
Apigenina , Membrana Celular , Transportador de Glucose Tipo 1 , Glicólise , Complexo de Golgi , Telúrio , Humanos , Glicólise/efeitos dos fármacos , Complexo de Golgi/metabolismo , Complexo de Golgi/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Transportador de Glucose Tipo 1/metabolismo , Apigenina/administração & dosagem , Apigenina/farmacologia , Telúrio/administração & dosagem , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Glucose/metabolismo
9.
Mol Cancer ; 23(1): 107, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38760815

RESUMO

Neutrophils play a Janus-faced role in the complex landscape of cancer pathogenesis and immunotherapy. As immune defense cells, neutrophils release toxic substances, including reactive oxygen species and matrix metalloproteinase 9, within the tumor microenvironment. They also modulate the expression of tumor necrosis factor-related apoptosis-inducing ligand and Fas ligand, augmenting their capacity to induce tumor cell apoptosis. Their involvement in antitumor immune regulation synergistically activates a network of immune cells, bolstering anticancer effects. Paradoxically, neutrophils can succumb to the influence of tumors, triggering signaling cascades such as JAK/STAT, which deactivate the immune system network, thereby promoting immune evasion by malignant cells. Additionally, neutrophil granular constituents, such as neutrophil elastase and vascular endothelial growth factor, intricately fuel tumor cell proliferation, metastasis, and angiogenesis. Understanding the mechanisms that guide neutrophils to collaborate with other immune cells for comprehensive tumor eradication is crucial to enhancing the efficacy of cancer therapeutics. In this review, we illuminate the underlying mechanisms governing neutrophil-mediated support or inhibition of tumor progression, with a particular focus on elucidating the internal and external factors that influence neutrophil polarization. We provide an overview of recent advances in clinical research regarding the involvement of neutrophils in cancer therapy. Moreover, the future prospects and limitations of neutrophil research are discussed, aiming to provide fresh insights for the development of innovative cancer treatment strategies targeting neutrophils.


Assuntos
Imunoterapia , Neoplasias , Neutrófilos , Microambiente Tumoral , Humanos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/metabolismo , Neoplasias/patologia , Imunoterapia/métodos , Microambiente Tumoral/imunologia , Animais , Transdução de Sinais
10.
Talanta ; 274: 125920, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574532

RESUMO

Herby, the interaction of metallothioneins with commonly used Pt-based anticancer drugs - cisplatin, carboplatin, and oxaliplatin - was investigated using the combined power of elemental (i.e. LA-ICP-MS, CE-ICP-MS) and molecular (i.e. MALDI-TOF-MS) analytical techniques providing not only required information about the interaction, but also the benefit of low sample consumption. The amount of Cd and Pt incorporated within the protein was determined for protein monomers and dimer/oligomers formed by non-oxidative dimerization. Moreover, fluorescence spectrometry using Zn2+-selective fluorescent indicator - FluoZin3 - was employed to monitor the ability of Pt drugs to release natively occurring Zn from the protein molecule. The investigation was carried out using two protein isoforms (i.e. MT2, MT3), and significant differences in behaviour of these two isoforms were observed. The main attention was paid to elucidating whether the protein dimerization/oligomerization may be the reason for the potential failure of the anticancer therapy based on these drugs. Based on the results, it was demonstrated that the interaction of MT2 (both monomers and dimers) interacted with Pt drugs significantly less compared to MT3 (both monomers and dimers). Also, a significant difference between monomeric and dimeric forms (both MT2 and MT3) was not observed. This may suggest that dimer formation is not the key factor leading to the inactivation of Pt drugs.


Assuntos
Metalotioneína , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Metalotioneína/metabolismo , Metalotioneína/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Fluorescência/métodos , Carboplatina/farmacologia , Oxaliplatina/farmacologia , Cisplatino/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/química , Platina/química , Metalotioneína 3 , Citostáticos/farmacologia , Citostáticos/química , Espectrometria de Massas/métodos , Humanos
11.
Biomark Res ; 12(1): 38, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594765

RESUMO

BACKGROUND & AIMS: Metallothionein-3 (hMT3) is a structurally unique member of the metallothioneins family of low-mass cysteine-rich proteins. hMT3 has poorly characterized functions, and its importance for hepatocellular carcinoma (HCC) cells has not yet been elucidated. Therefore, we investigated the molecular mechanisms driven by hMT3 with a special emphasis on susceptibility to sorafenib. METHODS: Intrinsically sorafenib-resistant (BCLC-3) and sensitive (Huh7) cells with or without up-regulated hMT3 were examined using cDNA microarray and methods aimed at mitochondrial flux, oxidative status, cell death, and cell cycle. In addition, in ovo/ex ovo chick chorioallantoic membrane (CAM) assays were conducted to determine a role of hMT3 in resistance to sorafenib and associated cancer hallmarks, such as angiogenesis and metastastic spread. Molecular aspects of hMT3-mediated induction of sorafenib-resistant phenotype were delineated using mass-spectrometry-based proteomics. RESULTS: The phenotype of sensitive HCC cells can be remodeled into sorafenib-resistant one via up-regulation of hMT3. hMT3 has a profound effect on mitochondrial respiration, glycolysis, and redox homeostasis. Proteomic analyses revealed a number of hMT3-affected biological pathways, including exocytosis, glycolysis, apoptosis, angiogenesis, and cellular stress, which drive resistance to sorafenib. CONCLUSIONS: hMT3 acts as a multifunctional driver capable of inducing sorafenib-resistant phenotype of HCC cells. Our data suggest that hMT3 and related pathways could serve as possible druggable targets to improve therapeutic outcomes in patients with sorafenib-resistant HCC.

12.
Biosens Bioelectron ; 250: 116050, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38301543

RESUMO

Low-cost, rapid, and easy-to-use biosensors for various cancer biomarkers are of utmost importance in detecting cancer biomarkers for early-stage metastasis control and efficient diagnosis. The molecular complexity of cancer biomarkers is overwhelming, thus, the repeatability and reproducibility of measurements by biosensors are critical factors. Electrochemical biosensors are attractive alternatives in cancer diagnosis due to their low cost, simple operation, and promising analytical figures of merit. Recently graphene-derived nanostructures have been used extensively for the fabrication of electrochemical biosensors because of their unique physicochemical properties, including the high electrical conductivity, adsorption capacity, low cost and ease of mass production, presence of oxygen-containing functional groups that facilitate the bioreceptor immobilization, increased flexibility and mechanical strength, low cellular toxicity. Indeed, these properties make them advantageous compared to other alternatives. However, some drawbacks must be overcome to extend their use, such as poor and uncontrollable deposition on the substrate due to the low dispersity of some graphene materials and irreproducibility of the results because of the differences in various batches of the produced graphene materials. This review has documented the most recently developed strategies for electrochemical sensor fabrication. It differs in the categorization method compared to published works to draw greater attention to the wide opportunities of graphene nanomaterials for biological applications. Limitations and future scopes are discussed to advance the integration of novel technologies such as artificial intelligence, the internet of medical things, and triboelectric nanogenerators to eventually increase efficacy and efficiency.


Assuntos
Técnicas Biossensoriais , Grafite , Nanoestruturas , Neoplasias , Biomarcadores Tumorais , Grafite/química , Inteligência Artificial , Reprodutibilidade dos Testes , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Nanoestruturas/química , Neoplasias/diagnóstico
13.
Ecotoxicol Environ Saf ; 270: 115823, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176180

RESUMO

Two-dimensional materials have recently gained significant awareness. A representative of such materials, black phosphorous (BP), earned attention based on its comprehensive application potential. The presented study focuses on the mode of cellular response underlying the BP interaction with Chlamydomonas reinhardtii as an algal model organism. We observed noticeable ROS formation and changes in outer cellular topology after 72 h of incubation at 5 mg/L BP. Transcriptome profiling was employed to examine C. reinhardtii response after exposure to 25 mg/L BP for a deeper understanding of the associated processes. The RNA sequencing has revealed a comprehensive response with abundant transcript downregulation. The mode of action was attributed to cell wall disruption, ROS elevation, and chloroplast disturbance. Besides many other dysregulated genes, the cell response involved the downregulation of GH9 and gametolysin within a cell wall, pointing to a shift to discrete manipulation with resources. The response also included altered expression of the PRDA1 gene associated with redox governance in chloroplasts implying ROS disharmony. Altered expression of the Cre-miR906-3p, Cre-miR910, and Cre-miR914 pointed to those as potential markers in stress response studies.


Assuntos
Chlamydomonas reinhardtii , Chlamydomonas reinhardtii/metabolismo , Transcriptoma , Fósforo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Compreensão , Cloroplastos/genética , Cloroplastos/metabolismo
14.
Acta Pharm Sin B ; 13(12): 5030-5047, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38045041

RESUMO

Liver fibrosis is a reversible pathological process caused by chronic liver damage and a major risk factor for hepatocellular carcinoma (HCC). Hepatic stellate cell (HSC) activation is considered the main target for liver fibrosis therapy. However, the efficiency of this strategy is limited due to the complex microenvironment of liver fibrosis, including excessive extracellular matrix (ECM) deposition and hypoxia-induced imbalanced ECM metabolism. Herein, nilotinib (NIL)-loaded hyaluronic acid (HA)-coated Ag@Pt nanotriangular nanozymes (APNH NTs) were developed to inhibit HSCs activation and remodel the microenvironment of liver fibrosis. APNH NTs efficiently eliminated intrahepatic reactive oxygen species (ROS) due to their inherent superoxide dismutase (SOD) and catalase (CAT) activities, thereby downregulating the expression of NADPH oxidase-4 (NOX-4) and inhibiting HSCs activation. Simultaneously, the oxygen produced by the APNH NTs further alleviated the hypoxic microenvironment. Importantly, the released NIL promoted collagen depletion by suppressing the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1), thus synergistically remodeling the microenvironment of liver fibrosis. Notably, an in vivo study in CCl4-induced mice revealed that APNH NTs exhibited significant antifibrogenic effects without obvious long-term toxicity. Taken together, the data from this work suggest that treatment with the synthesized APNH NTs provides an enlightening strategy for remodeling the microenvironment of liver fibrosis with boosted antifibrogenic activity.

15.
Infect Drug Resist ; 16: 7365-7375, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38050628

RESUMO

Purpose: Resistance of pathogenic strains of Escherichia coli to ß-lactams, particularly to ampicillin, is on the rise and it is attributed to intrinsic and acquired mechanisms. One important factor contributing to resistance, together with primarily resistance mechanisms, is a mutation and/or an over-expression of the intrinsic efflux pumps in the resistance-nodulation-division (RND) superfamily. Among these efflux pumps, AcrA, AcrB, TolC, and AcrD play an important role in antimicrobial co-resistance, including resistance to ß-lactams. Materials and Methods: Twelve E. coli isolates obtained from patients' wounds and the control strain of E. coli ATCC 25922 were analyzed. The phenotypic resistance of these isolates to selected ß-lactams was assessed by determination of the minimal inhibitory concentration. Additionally, the prevalence of ß-lactamase genes (blaTEM, blaCTX-M, blaSHV, and blaAmpC) was screened by PCR. Real-time qPCR was used to determine the expression of the selected efflux pumps acrA, acrB, tolC, and acrD and the repressor acrR after the exposure of E. coli to ampicillin. Results: Phenotypic resistance to ß-lactams was detected in seven isolates, mainly to ampicillin and piperacillin. This was corroborated by the presence of at least one acquired bla gene in each of these isolates. Although E. coli strains varied in the expression of RND-family efflux pumps after the ampicillin exposure, their gene expression indicated that these pumps did not play a major role in the phenotypic resistance to ampicillin. Conclusion: Each E. coli isolate displayed unique characteristics, differing in minimum inhibitory concentration (MIC) values, prevalence of acquired blaTEM and blaCTX-M genes, and expression of the RND-family pumps. This together demonstrates that these clinical isolates employed distinct intrinsic or acquired resistance pathways for their defense against ampicillin. The prevalence and spread of ampicillin resistant E. coli has to be monitored and the search for ampicillin alternatives is needed.

16.
mSystems ; 8(6): e0073323, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37905937

RESUMO

IMPORTANCE: A long-term exposure of bacteria to zinc oxide and zinc oxide nanoparticles leads to major alterations in bacterial morphology and physiology. These included biochemical and physiological processes promoting the emergence of strains with multi-drug resistance and virulence traits. After the removal of zinc pressure, bacterial phenotype reversed back to the original state; however, certain changes at the genomic, transcriptomic, and proteomic level remained. Why is this important? The extensive and intensive use of supplements in animal feed effects the intestinal microbiota of livestock and this may negatively impact the health of animals and people. Therefore, it is crucial to understand and monitor the impact of feed supplements on intestinal microorganisms in order to adequately assess and prevent potential health risks.


Assuntos
Óxido de Zinco , Zinco , Humanos , Animais , Zinco/farmacologia , Óxido de Zinco/química , Escherichia coli/genética , Multiômica , Proteômica
17.
BMC Microbiol ; 23(1): 288, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803300

RESUMO

OBJECTIVES: Resistance to antibiotics among bacteria of clinical importance, including Staphylococcus aureus, is a serious problem worldwide and the search for alternatives is needed. Some metal complexes have antibacterial properties and when combined with antibiotics, they may increase bacterial sensitivity to antimicrobials. In this study, we synthesized the iron complex and tested it in combination with ampicillin (Fe16 + AMP) against S. aureus. METHODS: An iron complex (Fe16) was synthesized and characterized using spectroscopy methods. Confirmation of the synergistic effect between the iron complex (Fe16) and ampicillin (AMP) was performed using ζ-potential, infrared spectra and FICI index calculated from the minimum inhibitory concentration (MIC) from the checkerboard assay. Cytotoxic properties of combination Fe16 + AMP was evaluated on eukaryotic cell line. Impact of combination Fe16 + AMP on chosen genes of S. aureus were performed by Quantitative Real-Time PCR. RESULTS: The MIC of Fe16 + AMP was significantly lower than that of AMP and Fe16 alone. Furthermore, the infrared spectroscopy revealed the change in the ζ-potential of Fe16 + AMP. We demonstrated the ability of Fe16 + AMP to disrupt the bacterial membrane of S. aureus and that likely allowed for better absorption of AMP. In addition, the change in gene expression of bacterial efflux pumps at the sub-inhibitory concentration of AMP suggests an insufficient import of iron into the bacterial cell. At the same time, Fe16 + AMP did not have any cytotoxic effects on keratinocytes. CONCLUSIONS: Combined Fe16 + AMP therapy demonstrated significant synergistic and antimicrobial effects against S. aureus. This study supports the potential of combination therapy and further research.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Ampicilina/farmacologia , Sinergismo Farmacológico , Antibacterianos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana
18.
J Hazard Mater ; 460: 132450, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37708651

RESUMO

Over decades, synthetic dyes have become increasingly dominated by azo dyes posing a significant environmental risk due to their toxicity. Microalgae-based systems may offer an alternative for treatment of azo dye effluents to conventional physical-chemical methods. Here, microalgae were tested to decolorize industrial azo dye wastewater (ADW). Chlorella sorokiniana showed the highest decolorization efficiency in a preliminary screening test. Subsequently, the optimization of the experimental design resulted in 70% decolorization in a photobioreactor. Tolerance of this strain was evidenced using multiple approaches (growth and chlorophyll content assays, scanning electron microscopy (SEM), and antioxidant level measurements). Raman microspectroscopy was employed for the quantification of ADW-specific compounds accumulated by the microalgal biomass. Finally, RNA-seq revealed the transcriptome profile of C. sorokiniana exposed to ADW for 72 h. Activated DNA repair and primary metabolism provided sufficient energy for microalgal growth to overcome the adverse toxic conditions. Furthermore, several transporter genes, oxidoreductases-, and glycosyltransferases-encoding genes were upregulated to effectively sequestrate and detoxify the ADW. This work demonstrates the potential utilization of C. sorokiniana as a tolerant strain for industrial wastewater treatment, emphasizing the regulation of its molecular mechanisms to cope with unfavorable growth conditions.


Assuntos
Chlorella , Descoloração da Água , Chlorella/genética , Perfilação da Expressão Gênica , Corantes/toxicidade , Compostos Azo
19.
BMC Microbiol ; 23(1): 207, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37528354

RESUMO

BACKGROUND: The emergence of antibiotic resistance in pathogenic bacteria has become a global threat, encouraging the adoption of efficient and effective alternatives to conventional antibiotics and promoting their use as replacements. Titanium dioxide nanoparticles (TiO2 NPs) have been reported to exhibit antibacterial properties. In this study, we synthesized and characterized TiO2 NPs in anatase and rutile forms with surface modification by geraniol (GER). RESULTS: The crystallinity and morphology of modified TiO2 NPs were analyzed by UV/Vis spectrophotometry, X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) with elemental mapping (EDS). The antimicrobial activity of TiO2 NPs with geraniol was assessed against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli. The minimum inhibitory concentration (MIC) values of modified NPs ranged from 0.25 to 1.0 mg/ml against all bacterial strains, and the live dead assay and fractional inhibitory concentration (FIC) supported the antibacterial properties of TiO2 NPs with GER. Moreover, TiO2 NPs with GER also showed a significant decrease in the biofilm thickness of MRSA. CONCLUSIONS: Our results suggest that TiO2 NPs with GER offer a promising alternative to antibiotics, particularly for controlling antibiotic-resistant strains. The surface modification of TiO2 NPs by geraniol resulted in enhanced antibacterial properties against multiple bacterial strains, including antibiotic-resistant MRSA. The potential applications of modified TiO2 NPs in the biomedical and environmental fields warrant further investigation.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Antibacterianos/farmacologia , Bactérias , Testes de Sensibilidade Microbiana
20.
J Enzyme Inhib Med Chem ; 38(1): 2237209, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37489050

RESUMO

Phosphoinositide 3-kinases (PI3K) and phosphoinositide 3-kinase-related protein kinases (PIKK) are two structurally related families of kinases that play vital roles in cell growth and DNA damage repair. Dysfunction of PIKK members and aberrant stimulation of the PI3K/AKT/mTOR signalling pathway are linked to a plethora of diseases including cancer. In recent decades, numerous inhibitors related to the PI3K/AKT/mTOR signalling have made great strides in cancer treatment, like copanlisib and sirolimus. Notably, most of the PIKK inhibitors (such as VX-970 and M3814) related to DNA damage response have also shown good efficacy in clinical trials. However, these drugs still require a suitable combination therapy to overcome drug resistance or improve antitumor activity. Based on the aforementioned facts, we summarised the efficacy of PIKK, PI3K, and AKT inhibitors in the therapy of human malignancies and the resistance mechanisms of targeted therapy, in order to provide deeper insights into cancer treatment.


Assuntos
Neoplasias , Fosfatidilinositol 3-Quinase , Humanos , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
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