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1.
Cell ; 158(1): 25-40, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24995976

RESUMO

Obesity and diabetes affect more than half a billion individuals worldwide. Interestingly, the two conditions do not always coincide and the molecular determinants of "healthy" versus "unhealthy" obesity remain ill-defined. Chronic metabolic inflammation (metaflammation) is believed to be pivotal. Here, we tested a hypothesized anti-inflammatory role for heme oxygenase-1 (HO-1) in the development of metabolic disease. Surprisingly, in matched biopsies from "healthy" versus insulin-resistant obese subjects we find HO-1 to be among the strongest positive predictors of metabolic disease in humans. We find that hepatocyte and macrophage conditional HO-1 deletion in mice evokes resistance to diet-induced insulin resistance and inflammation, dramatically reducing secondary disease such as steatosis and liver toxicity. Intriguingly, cellular assays show that HO-1 defines prestimulation thresholds for inflammatory skewing and NF-κB amplification in macrophages and for insulin signaling in hepatocytes. These findings identify HO-1 inhibition as a potential therapeutic strategy for metabolic disease.


Assuntos
Heme Oxigenase-1/metabolismo , Resistência à Insulina , Proteínas de Membrana/metabolismo , Obesidade/complicações , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica , Hepatócitos/metabolismo , Humanos , Inflamação/metabolismo , Fígado/metabolismo , Macrófagos/metabolismo , Doenças Metabólicas/metabolismo , Doenças Metabólicas/fisiopatologia , Camundongos , Camundongos Knockout , Obesidade/fisiopatologia , Espécies Reativas de Oxigênio/metabolismo
3.
Nature ; 563(7732): 564-568, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30405245

RESUMO

Genetic regulators and environmental stimuli modulate T cell activation in autoimmunity and cancer. The enzyme co-factor tetrahydrobiopterin (BH4) is involved in the production of monoamine neurotransmitters, the generation of nitric oxide, and pain1,2. Here we uncover a link between these processes, identifying a fundamental role for BH4 in T cell biology. We find that genetic inactivation of GTP cyclohydrolase 1 (GCH1, the rate-limiting enzyme in the synthesis of BH4) and inhibition of sepiapterin reductase (the terminal enzyme in the synthetic pathway for BH4) severely impair the proliferation of mature mouse and human T cells. BH4 production in activated T cells is linked to alterations in iron metabolism and mitochondrial bioenergetics. In vivo blockade of BH4 synthesis abrogates T-cell-mediated autoimmunity and allergic inflammation, and enhancing BH4 levels through GCH1 overexpression augments responses by CD4- and CD8-expressing T cells, increasing their antitumour activity in vivo. Administration of BH4 to mice markedly reduces tumour growth and expands the population of intratumoral effector T cells. Kynurenine-a tryptophan metabolite that blocks antitumour immunity-inhibits T cell proliferation in a manner that can be rescued by BH4. Finally, we report the development of a potent SPR antagonist for possible clinical use. Our data uncover GCH1, SPR and their downstream metabolite BH4 as critical regulators of T cell biology that can be readily manipulated to either block autoimmunity or enhance anticancer immunity.


Assuntos
Doenças Autoimunes/imunologia , Biopterinas/análogos & derivados , Neoplasias/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Administração Oral , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/metabolismo , Animais , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/patologia , Biopterinas/biossíntese , Biopterinas/metabolismo , Biopterinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Coenzimas/metabolismo , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Feminino , GTP Cicloidrolase/genética , GTP Cicloidrolase/metabolismo , Humanos , Hipersensibilidade/imunologia , Ferro/metabolismo , Cinurenina/metabolismo , Cinurenina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
4.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396952

RESUMO

Mitochondrial dysfunction and glutamate toxicity are associated with neural disorders, including brain trauma. A review of the literature suggests that toxic and transmission actions of neuronal glutamate are spatially and functionally separated. The transmission pathway utilizes synaptic GluN2A receptors, rapidly released pool of glutamate, evoked release of glutamate mediated by Synaptotagmin 1 and the amount of extracellular glutamate regulated by astrocytes. The toxic pathway utilizes extrasynaptic GluN2B receptors and a cytoplasmic pool of glutamate, which results from the spontaneous release of glutamate mediated by Synaptotagmin 7 and the neuronal 2-oxoglutarate dehydrogenase complex (OGDHC), a tricarboxylic acid (TCA) cycle enzyme. Additionally, the inhibition of OGDHC observed upon neuro-inflammation is due to an excessive release of reactive oxygen/nitrogen species by immune cells. The loss of OGDHC inhibits uptake of glutamate by mitochondria, thus facilitating its extracellular accumulation and stimulating toxic glutamate pathway without affecting transmission. High levels of extracellular glutamate lead to dysregulation of intracellular redox homeostasis and cause ferroptosis, excitotoxicity, and mitochondrial dysfunction. The latter affects the transmission pathway demanding high-energy supply and leading to cell death. Mitochondria aggravate glutamate toxicity due to impairments in the TCA cycle and become a victim of glutamate toxicity, which disrupts oxidative phosphorylation. Thus, therapies targeting the TCA cycle in neurological disorders may be more efficient than attempting to preserve mitochondrial oxidative phosphorylation.


Assuntos
Ácido Glutâmico , Doenças Mitocondriais , Humanos , Ácido Glutâmico/metabolismo , Mitocôndrias/metabolismo , Ciclo do Ácido Cítrico , Espécies Reativas de Oxigênio/metabolismo , Inflamação/metabolismo , Doenças Mitocondriais/metabolismo
5.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612675

RESUMO

There is a growing body of evidence that ER stress and the unfolded protein response (UPR) play a key role in numerous diseases. Impaired liver perfusion and ER stress often accompany each other in liver diseases. However, the exact impact of ER stress and UPR on the hepatic perfusion is not fully understood. The aim of this study was to disclose the effect of ER stress and UPR on the size of liver vessels and on the levels of Ca2+ and nitric oxide (NO), critical regulators of vascular tonus. This study was carried out in precisely cut liver tissue slices. Confocal microscopy was used to create 3D images of vessels. NO levels were determined either using either laser scan microscopy (LSM) in cells or by NO-analyser in medium. Ca2+ levels were analysed by LSM. We show that tunicamycin, an inducer of ER stress, acts similarly with vasodilator acetylcholine. Both exert a similar effect on the NO and Ca2+ levels; both induce significant vasodilation. Notably, this vasodilative effect persisted despite individual inhibition of UPR pathways-ATF-6, PERK, and IRE1-despite confirming the activation of UPR. Experiments with HUVEC cells showed that elevated NO levels did not result from endothelial NO synthase (eNOS) activation. Our study suggests that tunicamycin-mediated ER stress induces liver vessel vasodilation in an NO-dependent manner, which is mediated by intracellular nitrodilator-activatable NO store (NANOS) in smooth muscle cells rather than by eNOS.


Assuntos
Estresse do Retículo Endoplasmático , Vasodilatação , Tunicamicina/farmacologia , Resposta a Proteínas não Dobradas , Fígado
6.
Org Biomol Chem ; 21(42): 8477-8481, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37850356

RESUMO

A straightforward and selective way for the preparation of amides from nitroarenes and carboxylic acids using carbon monoxide as a reductant was developed. This protocol does not require any non-gaseous additives, thus simplifying product isolation. Aliphatic carboxylic acid was modified in the presence of aromatic ones, and reducible functional groups such as CC, Ar-Br, and R-NO2 were saved.

7.
Sensors (Basel) ; 23(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37687982

RESUMO

Prostate cancer (PC) is one of the major causes of death among elderly men. PC is often diagnosed later in progression due to asymptomatic early stages. Early detection of PC is thus crucial for effective PC treatment. The aim of this study is the simultaneous highly sensitive detection of a palette of PC-associated microRNAs (miRNAs) in human plasma samples. With this aim, a nanoribbon biosensor system based on "silicon-on-insulator" structures (SOI-NR biosensor) has been employed. In order to provide biospecific detection of the target miRNAs, the surface of individual nanoribbons has been sensitized with DNA oligonucleotide probes (oDNA probes) complementary to the target miRNAs. The lowest concentration of nucleic acids, detectable with our biosensor, has been found to be 1.1 × 10-17 M. The successful detection of target miRNAs, isolated from real plasma samples of PC patients, has also been demonstrated. We believe that the development of highly sensitive nanotechnology-based biosensors for the detection of PC markers is a step towards personalized medicine.


Assuntos
MicroRNAs , Nanotubos de Carbono , Ácidos Nucleicos , Neoplasias da Próstata , Idoso , Masculino , Humanos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Nanotecnologia
8.
Int J Mol Sci ; 24(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37240343

RESUMO

Mass spectrometry (MS) is one of the main techniques for protein identification. Herein, MS has been employed for the identification of bovine serum albumin (BSA), which was covalently immobilized on the surface of a mica chip intended for investigation by atomic force microscopy (AFM). For the immobilization, two different types of crosslinkers have been used: 4-benzoylbenzoic acid N-succinimidyl ester (SuccBB) and dithiobis(succinimidyl propionate) (DSP). According to the data obtained by using an AFM-based molecular detector, the SuccBB crosslinker was more efficient in BSA immobilization than the DSP. The type of crosslinker used for protein capturing has been found to affect the results of MS identification. The results obtained herein can be applied in the development of novel systems intended for the highly sensitive analysis of proteins with molecular detectors.


Assuntos
Soroalbumina Bovina , Microscopia de Força Atômica/métodos , Soroalbumina Bovina/química , Espectrometria de Massas/métodos
9.
Int J Mol Sci ; 25(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38203578

RESUMO

This work demonstrates the use of a modified mica to concentrate proteins, which is required for proteomic profiling of blood plasma by mass spectrometry (MS). The surface of mica substrates, which are routinely used in atomic force microscopy (AFM), was modified with a photocrosslinker to allow "irreversible" binding of proteins via covalent bond formation. This modified substrate was called the AFM chip. This study aimed to determine the role of the surface and crosslinker in the efficient concentration of various types of proteins in plasma over a wide concentration range. The substrate surface was modified with a 4-benzoylbenzoic acid N-succinimidyl ester (SuccBB) photocrosslinker, activated by UV irradiation. AFM chips were incubated with plasma samples from a healthy volunteer at various dilution ratios (102X, 104X, and 106X). Control experiments were performed without UV irradiation to evaluate the contribution of physical protein adsorption to the concentration efficiency. AFM imaging confirmed the presence of protein layers on the chip surface after incubation with the samples. MS analysis of different samples indicated that the proteomic profile of the AFM-visualized layers contained common and unique proteins. In the working series of experiments, 228 proteins were identified on the chip surface for all samples, and 21 proteins were not identified in the control series. In the control series, a total of 220 proteins were identified on the chip surface, seven of which were not found in the working series. In plasma samples at various dilution ratios, a total of 146 proteins were identified without the concentration step, while 17 proteins were not detected in the series using AFM chips. The introduction of a concentration step using AFM chips allowed us to identify more proteins than in plasma samples without this step. We found that AFM chips with a modified surface facilitate the efficient concentration of proteins owing to the adsorption factor and the formation of covalent bonds between the proteins and the chip surface. The results of our study can be applied in the development of highly sensitive analytical systems for determining the complete composition of the plasma proteome.


Assuntos
Proteínas Sanguíneas , Proteômica , Humanos , Silicatos de Alumínio , Espectrometria de Massas
10.
Psychiatr Danub ; 35(Suppl 2): 141-149, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800217

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) is a trauma- or stressor-related mental health condition with high socioeconomic burden. We aimed in this review to identify promising genetic markers predisposing for PTSD, which might serve in the design subsequent studies aiming to develop PTSD prevention and remediation measures. SUBJECTS AND METHODS: Our search queries in the PubMed database yielded 547 articles, of which 20 met our inclusion criteria for further analysis: published between 2018 and 2022, original research, containing molecular-genetic and statistical data, containing diagnosis verification methods, PTSD as a primary condition, and a sample of at least 60 patients. RESULTS: Among the 20 analyzed studies were reports of significant associations between PTSD and: FKBP5 variants rs9470080, regardless of the C or T allele; two FKBP5 haplotypes (A-G-C-C and A-G-C-T); gene-gene DRDхANNK1-COMT (rs1800497 × rs6269) and OXTR-DRD2 (rs2268498 × rs1801028); C-allele of CRHR1 (rs1724402). Other findings, such as the association of FKBP5 haplotypes (A-G-C-C, A-G-C-T) and the FKBP5-CRHR1 genotype, were of lesser statistical significance and less extensively studied. CONCLUSIONS: Although our literature analysis implicates certain genetic factors in PTSD, our understanding of the polygenic nature underlying the disorder remains limited, especially considering the hitherto underexplored epigenetic mechanisms. Future research endeavors should prioritize exploring these aspects to provide a more nuanced understanding of PTSD and its genetic underpinnings.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/genética , Transtornos de Estresse Pós-Traumáticos/prevenção & controle , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Haplótipos , Polimorfismo de Nucleotídeo Único , Genótipo , Alelos
11.
Int J Clin Oncol ; 27(3): 626-632, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34826011

RESUMO

OBJECTIVES: Therapy of patients with relapsed and refractory classic Hodgkin lymphoma (r/r cHL) after PD-1 inhibitors failure remains an unresolved issue. The aim of this study was to evaluate the efficacy and safety of the combination of nivolumab with brentuximab vedotin (Nivo + BV) after nivolumab monotherapy failure. METHODS: This study retrospectively analyzed 21 patients with r/r cHL who were treated with the combination of Nivo + BV after Nivo failure. The response was evaluated by PET-CT scan according to the LYRIC criteria. Adverse events (AEs) were assessed according to NCI CTCAE v.4.03. RESULTS: Median follow-up was 19 (9-47) months. The ORR was 57%. The median OS was not reached, 24 month OS was 80% (95% CI 50-93%). Median PFS was 12 months with 24 month PFS of 31% (95% CI 12-53%). Any grade AEs were observed in 12 patients (63%), 3-4 grade AEs in 2 patients (10%). Allogeneic hematopoietic stem cell transplantation (allo-HSCT) after Nivo + BV was performed in 8 (38%) patients. The median time between Nivo + BV and allo-HSCT was 8 (5-21) months. CONCLUSIONS: Combination of Nivo + BV in r/r cHL after nivolumab monotherapy failure is potentially an effective and safe approach.


Assuntos
Doença de Hodgkin , Nivolumabe , Brentuximab Vedotin , Doença de Hodgkin/tratamento farmacológico , Humanos , Nivolumabe/efeitos adversos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos
12.
Klin Lab Diagn ; 67(6): 380-384, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35749605

RESUMO

The rapid spread of a new coronavirus infection in the country actualizes the conduct of bacteriological studies of clinical material obtained from the respiratory tract of patients with COVID-19. During the experiments, 230 sputum samples and 260 autopsy lung samples from patients with COVID-19 were analyzed. 946 high-risk strains were isolated and identified by MALDI-ToF mass spectrometry on a Microflex LT instrument (Bruker®). According to the results of bacteriological cultures of sputum, a predominance of gram-positive ones was revealed, amounting to 50.5% (222 strains) of the total number of isolated pathogens. However, falling into this group is manifested by natural representatives of the microflora of the human mucous membranes from the genera Streptococcus, Rothia and Lactobacillus (109 strains in total), which can be manifested by the detection of improper sputum collection, causing contamination by the substance of intense salivation and nasopharyngeal discharge. In turn, the "classic" gram-positive causative agents of pneumonia were detected much less frequently: S. aureus in 5 cases, S. pneumoniae in 6 patients. The causative agents in the order Enterobacterales are represented by 42 strains, among which the most likely species are K.pneumoniae (27 strains). In the group of non-fermenting gram-negative bacteria, A. baumanii (29 strains) prevailed, and P. aeruginosa was also identified in 2 cases. When analyzing the results of a microbiological study of autopsy material (lungs) of patients with COVID-19, significant differences in the qualitative and quantitative composition of the microflora were revealed, compared with sputum. In the group of gram-positive bacteria, 15 strains of the natural microflora of the mucous membranes were identified, while sensitive species dominated among gram-negative pathogens: K. pneumoniae (102 strains), A. baumanii (75 strains), P. aeruginosa (11 strains). Regular microbiological monitoring is essential for antibiotic therapy and prevention of secondary bacterial infection. In the event of a fatal outcome, the results of microbiological analysis of autopsy material can determine the cause of death of the patient.


Assuntos
COVID-19 , Escarro , Antibacterianos/uso terapêutico , Autopsia , Bactérias Gram-Positivas , Humanos , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , Staphylococcus aureus , Streptococcus pneumoniae
13.
Ann Hematol ; 100(3): 691-698, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33528609

RESUMO

Immune checkpoint inhibitors (ICI) have demonstrated high therapeutic efficacy in relapsed or refractory classical Hodgkin lymphoma (r/r cHL). Nevertheless, despite the accumulated data, the question of the ICI therapy duration and efficacy of nivolumab retreatment remains unresolved. In this retrospective study, in a cohort of 23 adult patients with r/r cHL who discontinued nivolumab in complete response (CR), the possibility of durable remission achievement (2-year PFS was 55.1%) was demonstrated. Retreatment with nivolumab has demonstrated efficacy with high overall response rate (ORR) and CR (67% and 33.3% respectively). At the final analysis, all patients were alive with median PFS of 16.5 months. Grade 3-4 adverse events (AEs) were reported in 36% of patients, and there was no deterioration in terms of nivolumab retreatment-associated complications.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Nivolumabe/administração & dosagem , Adulto , Estudos de Coortes , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Nivolumabe/efeitos adversos , Recidiva , Retratamento , Estudos Retrospectivos , Resultado do Tratamento , Suspensão de Tratamento , Adulto Jovem
14.
Acta Neurochir (Wien) ; 163(1): 139-149, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32839865

RESUMO

BACKGROUND: Cerebral ischemia and neuroinflammation following aneurysmal subarachnoid hemorrhage (SAH) are major contributors to poor neurological outcome. Our study set out to investigate in an exploratory approach the interaction between NO and energy metabolism following SAH as both hypoxia and inflammation are known to affect nitric oxide (NO) metabolism and NO in turn affects mitochondria. METHODS: In seven patients under continuous multimodality neuromonitoring suffering poor-grade aneurysmal SAH, cerebral metabolism and NO levels (determined as a sum of nitrite plus nitrate) were determined in cerebral microdialysate for 14 days following SAH. In additional ex vivo experiments, rat cortex homogenate was subjected to the NO concentrations determined in SAH patients to test whether these NO concentrations impair mitochondrial function (determined by means of high-resolution respirometry). RESULTS: NO levels showed biphasic kinetics with drastically increased levels during the first 7 days (74.5 ± 29.9 µM) and significantly lower levels thereafter (47.5 ± 18.7 µM; p = 0.02). Only during the first 7 days, NO levels showed a strong negative correlation with brain tissue oxygen tension (r = - 0.78; p < 0.001) and a positive correlation with cerebral lactate (r = 0.79; p < 0.001), pyruvate (r = 0.68; p < 0.001), glutamate (r = 0.65; p < 0.001), as well as the lactate-pyruvate ratio (r = 0.48; p = 0.01), suggesting mitochondrial dysfunction. Ex vivo experiments confirmed that the increase in NO levels determined in patients during the acute phase is sufficient to impair mitochondrial function (p < 0.001). Mitochondrial respiration was inhibited irrespectively of whether glutamate (substrate of complex I) or succinate (substrate of complex II) was used as mitochondrial substrate suggesting the inhibition of mitochondrial complex IV. The latter was confirmed by direct determination of complex IV activity. CONCLUSIONS: Exploratory analysis of our data suggests that during the acute phase of SAH, NO plays a key role in the neuronal damage impairing mitochondrial function and facilitating accumulation of mitochondrial substrate; further studies are required to understand mechanisms underlying this observation.


Assuntos
Isquemia Encefálica/etiologia , Metabolismo Energético , Óxido Nítrico/metabolismo , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/metabolismo , Animais , Isquemia Encefálica/metabolismo , Cérebro/química , Cérebro/metabolismo , Feminino , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Humanos , Ácido Láctico/análise , Ácido Láctico/metabolismo , Masculino , Microdiálise , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Óxido Nítrico/análise , Ácido Pirúvico/análise , Ácido Pirúvico/metabolismo , Ratos
15.
Sensors (Basel) ; 21(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668578

RESUMO

Application of micro-Raman spectroscopy for the monitoring of quality of nanowire sensor chips fabrication has been demonstrated. Nanowire chips have been fabricated on the basis of «silicon-on-insulator¼ (SOI) structures (SOI-NW chips). The fabrication of SOI-NW chips was performed by optical litography with gas-phase etching. The so-fabricated SOI-NW chips are intended for highly sensitive detection of brain cancer biomarkers in humans. In our present study, two series of experiments have been conducted. In the first experimental series, detection of a synthetic DNA oligonucleotide (oDNA) analogue of brain cancer-associated microRNA miRNA-363 in purified buffer solution has been performed in order to demonstrate the high detection sensitivity. The second experimental series has been performed in order to reveal miRNA-363 itself in real human plasma samples. To provide detection biospecificity, the SOI-NW chip surface was modified by covalent immobilization of probe oligonucleotides (oDNA probes) complementary to the target biomolecules. Using the SOI-NW sensor chips proposed herein, the concentration detection limit of the target biomolecules at the level of 3.3 × 10-17 M has been demonstrated. Thus, the approach employing the SOI-NW chips proposed herein represents an attractive tool in biomedical practice, aimed at the early revelation of oncological diseases in humans.


Assuntos
Técnicas Biossensoriais , Neoplasias Encefálicas , MicroRNAs , Nanofios , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Humanos , MicroRNAs/genética , Plasma , Controle de Qualidade , Silício , Análise Espectral Raman
16.
Molecules ; 26(2)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435278

RESUMO

Atomic force microscopy (AFM)-based fishing is a promising method for the detection of low-abundant proteins. This method is based on the capturing of the target proteins from the analyzed solution onto a solid substrate, with subsequent counting of the captured protein molecules on the substrate surface by AFM. Protein adsorption onto the substrate surface represents one of the key factors determining the capturing efficiency. Accordingly, studying the factors influencing the protein adsorbability onto the substrate surface represents an actual direction in biomedical research. Herein, the influence of water motion in a flow-based system on the protein adsorbability and on its enzymatic activity has been studied with an example of horseradish peroxidase (HRP) enzyme by AFM, attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and conventional spectrophotometry. In the experiments, HRP solution was incubated in a setup modeling the flow section of a biosensor communication. The measuring cell with the protein solution was placed near a coiled silicone pipe, through which water was pumped. The adsorbability of the protein onto the surface of the mica substrate has been studied by AFM. It has been demonstrated that incubation of the HRP solution near the coiled silicone pipe with flowing water leads to an increase in its adsorbability onto mica. This is accompanied by a change in the enzyme's secondary structure, as has been revealed by ATR-FTIR. At the same time, its enzymatic activity remains unchanged. The results reported herein can be useful in the development of models describing the influence of liquid flow on the properties of enzymes and other proteins. The latter is particularly important for the development of biosensors for biomedical applications-particularly for serological analysis, which is intended for the early diagnosis of various types of cancer and infectious diseases. Our results should also be taken into account in studies of the effects of protein aggregation on hemodynamics, which plays a key role in human body functioning.


Assuntos
Peroxidase do Rábano Silvestre/isolamento & purificação , Água/química , Técnicas Biossensoriais , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Microscopia de Força Atômica , Estrutura Secundária de Proteína , Silicones/química , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Cytokine ; 124: 154577, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30446215

RESUMO

An excessive inflammatory response is frequently associated with cellular dysfunction and cell death. The latter may cause single and multiple organ failure. The most susceptible organs are liver, lung, kidney, heart and intestine. This review will focus on the liver as a target organ for an excessive inflammatory response. It is commonly accepted that organ failure is caused by the action of inflammatory cytokines released in excess during the inflammatory response. It has been suggested that inflammation mediated liver failure is not due to an increased death rate of parenchymal cells, but due to an intracellular metabolic disorder. This metabolic disorder is associated with mitochondrial and endoplasmic reticulum (ER) dysfunction during the acute phase response elicited by systemic inflammation. An overproduction of acute phase proteins in the liver as well as elevated reactive oxygen species (ROS) generation induce ER stress, triggering the unfolded protein response (UPR), which may initiate or aggravate inflammation. It is known that certain inflammatory mediators, such as the pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α induce ER stress. These findings suggest that ER stress and the subsequent UPR on the one hand, and the inflammatory response on the other create a kind of feed forward loop, which can be either beneficial (e.g., elimination of the pathogen and restoration of tissue homeostasis) or deleterious (e.g., excessive cell dysfunction and cell death). This review aims to unfurl the different pathways contributing to this loop and to highlight the relevance of UPR signaling (IRE1α, ATF6, and PERK) and mediators of the inflammatory response (NF-κB, STAT3, IL-1ß, IL-6, TLR) which have a particular role as pathophysiological triggers in the liver.


Assuntos
Estresse do Retículo Endoplasmático/genética , Mediadores da Inflamação/metabolismo , Hepatopatias/metabolismo , Fígado/metabolismo , Resposta a Proteínas não Dobradas/genética , Animais , Citocinas/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fígado/fisiologia , Hepatopatias/tratamento farmacológico , Hepatopatias/fisiopatologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Resposta a Proteínas não Dobradas/fisiologia
18.
Cytokine ; 124: 154569, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30389231

RESUMO

The rising prevalence of obesity came along with an increase in associated metabolic disorders in Western countries. Non-alcoholic fatty liver disease (NAFLD) represents the hepatic manifestation of the metabolic syndrome and is linked to primary stages of liver cancer development. Growth hormone (GH) regulates various vital processes such as energy supply and cellular regeneration. In addition, GH regulates various aspects of liver physiology through activating the Janus kinase (JAK) 2- signal transducer and activator of transcription (STAT) 5 pathway. Consequently, disrupted GH - JAK2 - STAT5 signaling in the liver alters hepatic lipid metabolism and is associated with NAFLD development in humans and mouse models. Interestingly, while STAT5 as well as JAK2 deficiency correlates with hepatic lipid accumulation, recent studies suggest that these proteins have unique ambivalent functions in chronic liver disease progression and tumorigenesis. In this review, we focus on the consequences of altered GH - JAK2 - STAT5 signaling for hepatic lipid metabolism and liver cancer development with an emphasis on lessons learned from genetic knockout models.


Assuntos
Carcinoma Hepatocelular/metabolismo , Hormônio do Crescimento/metabolismo , Janus Quinase 2/metabolismo , Neoplasias Hepáticas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fator de Transcrição STAT5/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Progressão da Doença , Humanos , Janus Quinase 2/genética , Metabolismo dos Lipídeos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/genética , Receptores de Glucocorticoides/metabolismo , Fator de Transcrição STAT5/genética , Transdução de Sinais/genética
19.
Biochim Biophys Acta Bioenerg ; 1859(9): 925-931, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29777685

RESUMO

BACKGROUND AND PURPOSE: Based on the fact that traumatic brain injury is associated with mitochondrial dysfunction we aimed at localization of mitochondrial defect and attempted to correct it by thiamine. EXPERIMENTAL APPROACH: Interventional controlled experimental animal study was used. Adult male Sprague-Dawley rats were subjected to lateral fluid percussion traumatic brain injury. Thiamine was administered 1 h prior to trauma; cortex was extracted for analysis 4 h and 3 d after trauma. KEY RESULTS: Increased expression of inducible nitric oxide synthase (iNOS) and tumor necrosis factor receptor 1 (TNF-R1) by 4 h was accompanied by a decrease in mitochondrial respiration with glutamate but neither with pyruvate nor succinate. Assays of TCA cycle flux-limiting 2-oxoglutarate dehydrogenase complex (OGDHC) and functionally linked enzymes (glutamate dehydrogenase, glutamine synthetase, pyruvate dehydrogenase, malate dehydrogenase and malic enzyme) indicated that only OGDHC activity was decreased. Application of the OGDHC coenzyme precursor thiamine rescued the activity of OGDHC and restored mitochondrial respiration. These effects were not mediated by changes in the expression of the OGDHC sub-units (E1k and E3), suggesting post-translational mechanism of thiamine effects. By the third day after TBI, thiamine treatment also decreased expression of TNF-R1. Specific markers of unfolded protein response did not change in response to thiamine. CONCLUSION AND IMPLICATIONS: Our data point to OGDHC as a major site of damage in mitochondria upon traumatic brain injury, which is associated with neuroinflammation and can be corrected by thiamine. Further studies are required to evaluate the pathological impact of these findings in clinical settings.


Assuntos
Biomarcadores/metabolismo , Lesões Encefálicas Traumáticas/fisiopatologia , Regulação da Expressão Gênica/efeitos dos fármacos , Complexo Cetoglutarato Desidrogenase/metabolismo , Mitocôndrias/fisiologia , Inflamação Neurogênica/prevenção & controle , Tiamina/farmacologia , Animais , Metabolismo Energético , Complexo Cetoglutarato Desidrogenase/antagonistas & inibidores , Complexo Cetoglutarato Desidrogenase/genética , Masculino , Mitocôndrias/efeitos dos fármacos , Inflamação Neurogênica/etiologia , Inflamação Neurogênica/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Oxirredução , Ratos , Ratos Sprague-Dawley , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Complexo Vitamínico B/farmacologia
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