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1.
J Biol Inorg Chem ; 26(7): 775-791, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34453218

RESUMO

The terminal N-mono- and dimethylated derivatives of an estrone-salicylaldehyde thiosemicarbazone hybrid and their highly cytotoxic Cu(II) complexes were synthesized and characterized in addition to their structurally related simpler bicyclic analogues. Solution stability and structure of the complexes were determined by UV-visible spectrophotometry and electron paramagnetic resonance spectroscopy. The monomethylation has a minor influence on the pKa values, while the dimethylation results in somewhat more acidic derivatives compared to the non-methylated derivatives, although all the compounds are neutral at physiological pH. Based on the speciation studies performed in a 30% (v/v) dimethyl sulfoxide/water mixture, the four novel ligands form fairly high-stability complexes with Cu(II) ions, in which they coordinate in mono-anionic (O‒,N,S) or di-anionic (O‒,N,S‒) binding modes. [CuLH‒1] species with (O‒,N,S‒)(H2O) coordination mode are present in solution at neutral pH, and these complexes were isolated and further studied. The Cu(II) complexes formed with the estrone hybrids were more stable in comparison with the bicyclic analogues. The terminal N-dimethylation results in the most stable complexes in a given ligand series. In vitro cytotoxicity of all the Cu(II) complexes was measured in 3D spheroids of HCT-116, A-549 and CH-1 human cancer cells which showed fairly low IC50 values (3.9‒17.1 µM). The Cu(II) complexes caused reduced tumour growth, and they activated the caspase-3 and caspase-7 endoproteases leading to apoptosis except the case of the complex formed with the monomethylated bicyclic derivative, where other type of mechanisms of action seems to induce the cell death. Anticancer Cu(II) complexes of mono- and dimethylated salicylaldehyde thiosemicarbazone-estrone hybrids possessing high solution stability and strong cytotoxic effect against 3D spheroids of a series of human cancer cells. 398x273 mm (150 x 150 DPI).


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Tiossemicarbazonas , Aldeídos , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Cobre , Cristalografia por Raios X , Estrona , Humanos , Ligantes , Tiossemicarbazonas/farmacologia
2.
Lupus ; 29(5): 455-462, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32070186

RESUMO

OBJECTIVES: Sodium (Na+) is stored in the skin and muscle and plays an important role in immune regulation. In animal models, increased tissue Na+ is associated with activation of the immune system, and high salt intake exacerbates autoimmune disease and worsens hypertension. However, there is no information about tissue Na+ and human autoimmune disease. We hypothesized that muscle and skin Na+ content is (a) higher in patients with systemic lupus erythematosus (SLE) than in control subjects, and (b) associated with blood pressure, disease activity, and inflammation markers (interleukin (IL)-6, IL-10 and IL-17 A) in SLE. METHODS: Lower-leg skin and muscle Na+ content was measured in 23 patients with SLE and in 28 control subjects using 23Na+ magnetic resonance imaging. Demographic and clinical information was collected from interviews and chart review, and blood pressure was measured. Disease activity was assessed using the SLE Disease Activity Index (SLEDAI). Plasma inflammation markers were measured by multiplex immunoassay. RESULTS: Muscle Na+ content was higher in patients with SLE (18.8 (16.7-18.3) mmol/L) than in control subjects (15.8 (14.7-18.3) mmol/L; p < 0.001). Skin Na+ content was also higher in SLE patients than in controls, but this difference was not statistically significant. Among patients with SLE, muscle Na+ was associated with SLEDAI and higher concentrations of IL-10 after adjusting for age, race, and sex. Skin Na+ was significantly associated with systolic blood pressure, but this was attenuated after covariate adjustment. CONCLUSION: Patients with SLE had higher muscle Na+ content than control subjects. In patients with SLE, higher muscle Na+ content was associated with higher disease activity and IL-10 concentrations.


Assuntos
Inflamação/metabolismo , Interleucina-10/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Isótopos de Sódio , Sódio/metabolismo , Adulto , Biomarcadores/metabolismo , Pressão Sanguínea , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculos/metabolismo , Pele/metabolismo
3.
J Evol Biol ; 29(10): 1968-1976, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27306988

RESUMO

Large brains (relative to body size) might confer fitness benefits to animals. Although the putative costs of well-developed brains can constrain the majority of species to modest brain sizes, these costs are still poorly understood. Given that the neural tissue is energetically expensive and demands antioxidants, one potential cost of developing and maintaining large brains is increased oxidative stress ('oxidation exposure' hypothesis). Alternatively, because large-brained species exhibit slow-paced life histories, they are expected to invest more into self-maintenance such as an efficacious antioxidative defence machinery ('oxidation avoidance' hypothesis). We predict decreased antioxidant levels and/or increased oxidative damage in large-brained species in case of oxidation exposure, and the contrary in case of oxidation avoidance. We address these contrasting hypotheses for the first time by means of a phylogenetic comparative approach based on an unprecedented data set of four redox state markers from 85 European bird species. Large-brained birds suffered less oxidative damage to lipids (measured as malondialdehyde levels) and exhibited higher total nonenzymatic antioxidant capacity than small-brained birds, whereas uric acid and glutathione levels were independent of brain size. These results were not altered by potentially confounding variables and did not depend on how relative brain size was quantified. Our findings partially support the 'oxidation avoidance' hypothesis and provide a physiological explanation for the linkage of large brains with slow-paced life histories: reduced oxidative stress of large-brained birds can secure brain functionality and healthy life span, which are integral to their lifetime fitness and slow-paced life history.


Assuntos
Aves/fisiologia , Encéfalo/anatomia & histologia , Estresse Oxidativo , Animais , Antioxidantes , Tamanho do Órgão , Filogenia
4.
Physiol Meas ; 45(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38478997

RESUMO

Objective.Photoplethysmography is a non-invasive optical technique that measures changes in blood volume within tissues. It is commonly and being increasingly used for a variety of research and clinical applications to assess vascular dynamics and physiological parameters. Yet, contrary to heart rate variability measures, a field which has seen the development of stable standards and advanced toolboxes and software, no such standards and limited open tools exist for continuous photoplethysmogram (PPG) analysis. Consequently, the primary objective of this research was to identify, standardize, implement and validate key digital PPG biomarkers.Approach.This work describes the creation of a standard Python toolbox, denotedpyPPG, for long-term continuous PPG time-series analysis and demonstrates the detection and computation of a high number of fiducial points and digital biomarkers using a standard fingerbased transmission pulse oximeter.Main results.The improved PPG peak detector had an F1-score of 88.19% for the state-of-the-art benchmark when evaluated on 2054 adult polysomnography recordings totaling over 91 million reference beats. The algorithm outperformed the open-source original Matlab implementation by ∼5% when benchmarked on a subset of 100 randomly selected MESA recordings. More than 3000 fiducial points were manually annotated by two annotators in order to validate the fiducial points detector. The detector consistently demonstrated high performance, with a mean absolute error of less than 10 ms for all fiducial points.Significance.Based on these fiducial points,pyPPGengineered a set of 74 PPG biomarkers. Studying PPG time-series variability usingpyPPGcan enhance our understanding of the manifestations and etiology of diseases. This toolbox can also be used for biomarker engineering in training data-driven models.pyPPGis available onhttps://physiozoo.com/.


Assuntos
Fotopletismografia , Processamento de Sinais Assistido por Computador , Frequência Cardíaca/fisiologia , Fotopletismografia/métodos , Polissonografia , Algoritmos , Biomarcadores
5.
Dalton Trans ; 53(11): 4984-5000, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38406993

RESUMO

In this study, we present the synthesis, characterization and in vitro cytotoxicity of six organometallic [Ru(II)(η6-p-cymene)(N,N)Cl]Cl, [Rh(III)(η5-C5Me5)(N,N)Cl]Cl and [Re(I)(CO)3(N,N)Cl] complexes, in which the (N,N) ligands are sterane-based 2,2'-bipyridine derivatives (4-Me-bpy-St-OH, 4-Ph-bpy-St-OH). The solution chemical behavior of the ligands and the complexes was explored by UV-visible spectrophotometry and 1H NMR spectroscopy. The ligands and their Re(I) complexes are neutral at pH = 7.40; this contributes to their highly lipophilic character (log D7.40 > +3). The Ru(II) and Rh(III) half-sandwich complexes are much more hydrophilic, and this property is greatly affected by the actual chloride ion content of the medium. The half-sandwich Ru and Rh complexes are highly stable in 30% (v/v) DMSO/water (<5% dissociation at pH = 7.40); this is further increased in water. The Rh(III)(η5-C5Me5) complexes were characterized by higher water/chloride exchange and pKa constants compared to their Ru(II)(η6-p-cymene) counterparts. The Re(I)(CO)3 complexes are also stable in solution over a wide pH range (2-12) without the release of the bidentate ligand; only the chlorido co-ligand can be replaced with OH- at higher pH values. A comprehensive discussion of the binding affinity of the half-sandwich Ru(II) and Rh(III) complexes toward human serum albumin and calf-thymus DNA is also provided. The Ru(II)(η6-p-cymene) complexes interact with human serum albumin via intermolecular forces, while for the Rh(III)(η5-C5Me5) complexes the coordinative binding mode is suggested as well. They are also able to interact with calf-thymus DNA, most likely via the coordination of the guanine nitrogen. The Ru(II)(η6-p-cymene) complexes were found to be the most promising among the tested compounds as they exhibited moderate-to-strong cytotoxic activity (IC50 = 3-11 µM) in LNCaP as well as in PC3 prostate cells in an androgen receptor-independent manner. They were also significantly cytotoxic in breast and colon adenocarcinoma cancer cell lines and showed good selectivity for cancer cells.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Complexos de Coordenação , Cimenos , Compostos Organometálicos , Rutênio , Humanos , Complexos de Coordenação/química , Linhagem Celular Tumoral , Ligantes , Cloretos/química , Antineoplásicos/química , DNA/química , Albumina Sérica Humana , Água , Rutênio/farmacologia , Rutênio/química , Compostos Organometálicos/farmacologia , Compostos Organometálicos/química
6.
Sci Rep ; 14(1): 3116, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326342

RESUMO

The congruency sequence effect (CSE) is one of the most investigated effects in the cognitive control literature. The conflict monitoring theory suggests that the CSE is the result of adjustments in cognitive control based on perceived conflict. A recent paper by Zhang and colleagues, has investigated whether the manipulation of conflict level by changing distractor incompatibility in a flanker task affects the amount of adjustments in cognitive control. Their study produced mixed findings, somewhat supporting the original conflict monitoring theory, but also suggesting other explanations, such as the repetition expectancy account. We replicated the experimental design in a multisite online study (N = 347), with Hungarian, Italian, and Singaporean participants. Our results supported the prediction that changes in the level of conflict trigger conflict adaptation, revealing that increasing conflict levels induced stronger adaptive control. Bayesian hypothesis testing indicated a monotonic reduction in congruency effects as a function of previous conflict strength. This finding is in line with the extension of the traditional conflict monitoring theory, as well as other theories like affective signaling and expected value of control, implying that the relationship between conflict and interference effects is gradual, rather than a binary function.


Assuntos
Conflito Psicológico , Projetos de Pesquisa , Humanos , Tempo de Reação , Teorema de Bayes , Cognição
7.
J Gen Physiol ; 155(4)2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36723516

RESUMO

CFTR chloride channel mutations cause the lethal and incurable disease cystic fibrosis (CF). CFTR is activated by phosphorylation, and phosphorylated channels exhibit "bursting" behavior-"bursts" of openings separated by short "flickery" closures and flanked by long "interburst" closures-driven by ATP binding/hydrolysis at two nucleotide-binding domains. The human channel (hCFTR) and the distant zebrafish ortholog (zCFTR) display differences both in their gating properties and structures. In phosphorylated ATP-bound hCFTR, the hR117 side chain, conserved across evolution, forms an H-bond that stabilizes the open state. Lack of that bond in the hR117H mutant causes CF. In the phosphorylated ATP-bound zCFTR structure that H-bond is not observable. Here, we show that the zR118H mutation does not affect the function of zCFTR. Instead, we identify an H-bond between the zS109 and zS120 side chains of phosphorylated ATP-bound, but not of unphosphorylated apo-, zCFTR. We investigate the role of that interaction using thermodynamic mutant cycles built on gating parameters determined in inside-out patch clamp recordings. We find that zS109 indeed forms an H-bond with zN120 in the flickery closed state, but not in the open or interburst closed states. Although in hCFTR an isoleucine (hI119) replaces the asparagine, mutation hS108A produces a strong hR117H-like phenotype. Since the effects of the latter two mutations are not additive, we conclude that in hCFTR these two positions interact, and the hS108-hR117 and hR117-hE1124 H-bonds cooperate to stabilize the open state. These findings highlight an example of how the gating mechanism was optimized during CFTR molecular evolution.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Animais , Humanos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/química , Trifosfato de Adenosina , Peixe-Zebra , Canais de Cloreto , Proteínas de Peixe-Zebra
8.
Elife ; 122023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37782012

RESUMO

CFTR, the anion channel mutated in cystic fibrosis patients, is a model ABC protein whose ATP-driven conformational cycle is observable at single-molecule level in patch-clamp recordings. Bursts of CFTR pore openings are coupled to tight dimerization of its two nucleotide-binding domains (NBDs) and in wild-type (WT) channels are mostly terminated by ATP hydrolysis. The slow rate of non-hydrolytic closure - which determines how tightly bursts and ATP hydrolysis are coupled - is unknown, as burst durations of catalytic site mutants span a range of ~200-fold. Here, we show that Walker A mutation K1250A, Walker B mutation D1370N, and catalytic glutamate mutations E1371S and E1371Q all completely disrupt ATP hydrolysis. True non-hydrolytic closing rate of WT CFTR approximates that of K1250A and E1371S. That rate is slowed ~15-fold in E1371Q by a non-native inter-NBD H-bond, and accelerated ~15-fold in D1370N. These findings uncover unique features of the NBD interface in human CFTR.


Assuntos
Trifosfato de Adenosina , Regulador de Condutância Transmembrana em Fibrose Cística , Humanos , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Trifosfato de Adenosina/metabolismo , Ativação do Canal Iônico , Mutação , Domínio Catalítico
9.
Sci Rep ; 13(1): 20283, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985809

RESUMO

AlphaFold2 (AF2) provides a 3D structure for every known or predicted protein, opening up new prospects for virtually every field in structural biology. However, working with transmembrane protein molecules pose a notorious challenge for scientists, resulting in a limited number of experimentally determined structures. Consequently, algorithms trained on this finite training set also face difficulties. To address this issue, we recently launched the TmAlphaFold database, where predicted AlphaFold2 structures are embedded into the membrane plane and a quality assessment (plausibility of the membrane-embedded structure) is provided for each prediction using geometrical evaluation. In this paper, we analyze how AF2 has improved the structural coverage of membrane proteins compared to earlier years when only experimental structures were available, and high-throughput structure prediction was greatly limited. We also evaluate how AF2 can be used to search for (distant) homologs in highly diverse protein families. By combining quality assessment and homology search, we can pinpoint protein families where AF2 accuracy is still limited, and experimental structure determination would be desirable.


Assuntos
Furilfuramida , Proteoma , Humanos , Proteínas de Membrana , Algoritmos , Bases de Dados Factuais
10.
ArXiv ; 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37502630

RESUMO

Efficient and accurate evaluation of long-term photoplethysmography (PPG) recordings is essential for both clinical assessments and consumer products. In 2021, the top opensource peak detectors were benchmarked on the Multi-Ethnic Study of Atherosclerosis (MESA) database consisting of polysomnography (PSG) recordings and continuous sleep PPG data, where the Automatic Beat Detector (Aboy) had the best accuracy. This work presents Aboy++, an improved version of the original Aboy beat detector. The algorithm was evaluated on 100 adult PPG recordings from the MESA database, which contains more than 4.25 million reference beats. Aboy++ achieved an F1-score of 85.5%, compared to 80.99% for the original Aboy peak detector. On average, Aboy++ processed a 1 hour-long recording in less than 2 seconds. This is compared to 115 seconds (i.e., over 57-times longer) for the open-source implementation of the original Aboy peak detector. This study demonstrated the importance of developing robust algorithms like Aboy++ to improve PPG data analysis and clinical outcomes. Overall, Aboy++ is a reliable tool for evaluating long-term wearable PPG measurements in clinical and consumer contexts. The open-source algorithm is available on the physiozoo.com website (on publication of this proceeding).

11.
J Steroid Biochem Mol Biol ; 231: 106315, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37086925

RESUMO

Dysfunction of the androgen receptor (AR) signalling axis plays a pivotal role in the development and progression of prostate cancer (PCa). Steroidal and non-steroidal AR antagonists can significantly improve the survival of PCa patients by blocking the action of the endogenous ligand through binding to the hormone receptor and preventing its activation. Herein, we report two synthetic strategies, each utilizing the advantages of microwave irradiation, to modify the A-ring of natural androgen 5α-dihydrotestosterone (DHT) with pyridine scaffolds. Treatment of DHT with appropriate Mannich salts led to 1,5-diketones, which were then converted with hydroxylamine to A-ring-fused 6'-substituted pyridines. To extend the compound library with 4',6'-disubstituted analogues, 2-arylidene derivatives of DHT were subjected to ring closure reactions according to the Kröhnke's pyridine synthesis. The crystal structure of a monosubstituted pyridine product was determined by single crystal X-ray diffraction. AR transcriptional activity in a reporter cell line was investigated for all novel A-ring-fused pyridines and a number of previously synthesized DHT-based quinolines were included to the biological study to obtain information about the structure-activity relationship. It was shown that several A-ring-fused quinolines acted as AR antagonists, in comparison with the dual or agonist character of the majority of A-ring-fused pyridines. Derivative 1d (A-ring-fused 6'-methoxyquinoline) was studied in detail and showed to be a low-micromolar AR antagonist (IC50 = 10.5 µM), and it suppressed the viability and proliferation of AR-positive PCa cell lines. Moreover, the candidate compound blocked the AR downstream signalling, induced moderate cell-cycle arrest and showed to bind recombinant AR and to target AR in cells. The binding mode and crucial interactions were described using molecular modelling.


Assuntos
Di-Hidrotestosterona , Neoplasias da Próstata , Masculino , Humanos , Di-Hidrotestosterona/farmacologia , Di-Hidrotestosterona/metabolismo , Micro-Ondas , Receptores Androgênicos/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Antagonistas de Receptores de Andrógenos/farmacologia , Piridinas/farmacologia
12.
Eur J Med Chem ; 249: 115086, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36682291

RESUMO

High expression of the androgen receptor (AR) and the disruption of its regulation are strongly responsible for the development of prostate cancer (PCa). Therapeutically relevant non-steroidal or steroidal antiandrogens are able to block the AR effect by eliminating AR-mediated signalling. Herein we report the synthesis of novel steroidal pyrazoles derived from the natural sex hormone 5α-dihydrotestosterone (DHT). 2-Ethylidene or 2-(hetero)arylidene derivatives of DHT obtained by regioselective Claisen-Schmidt condensation with acetaldehyde or (hetero)aromatic aldehydes in alkaline ethanol were reacted with monosubstituted hydrazines to give A-ring-fused 1,5-disubstituted pyrazoles as main or exclusive products, depending on the reaction conditions applied. Spontaneous or 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ)-induced oxidation of the primarily formed pyrazolines resulted in the desired products in moderate to good yields, while 17-oxidation also occurred by using the Jones reagent as a strong oxidant. Transcriptional activity of the AR in a reporter cell line was examined for all novel compounds, and several previously synthesized similar DHT-based pyrazoles with differently substituted heteroring were also included to obtain information about the structure-activity relationship. Two specific regioisomeric groups of derivatives significantly diminished the transcriptional activity of the AR in reporter cell line in 10 µM concentration, and displayed reasonable antiproliferative activity in AR-positive PCa cell lines. Lead compound (3d) was found to be a potent AR antagonist (IC50 = 1.18 µM), it generally suppressed AR signalling in time and dose dependent manner, moreover, it also led to a sharp decrease in wt-AR protein level probably caused by proteasomal degradation. We confirmed the antiproliferative activity of 3d in AR-positive PCa cell lines (with GI50 in low micromolar ranges), and its cellular, biochemical and in silico binding in AR ligand-binding domain. Moreover, compound 3d was shown to be potent even ex vivo in patient-derived tissues, which highlights the therapeutic potential of A-ring-fused pyrazoles.


Assuntos
Di-Hidrotestosterona , Neoplasias da Próstata , Masculino , Humanos , Di-Hidrotestosterona/farmacologia , Di-Hidrotestosterona/metabolismo , Receptores Androgênicos/metabolismo , Pirazóis , Regulação para Baixo , Linhagem Celular Tumoral , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Esteroides/uso terapêutico
13.
Sci Rep ; 12(1): 5904, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393447

RESUMO

S100 proteins are small, typically homodimeric, vertebrate-specific EF-hand proteins that establish Ca2+-dependent protein-protein interactions in the intra- and extracellular environment and are overexpressed in various pathologies. There are about 20 distinct human S100 proteins with numerous potential partner proteins. Here, we used a quantitative holdup assay to measure affinity profiles of most members of the S100 protein family against a library of chemically synthetized foldamers. The profiles allowed us to quantitatively map the binding promiscuity of each member towards the foldamer library. Since the library was designed to systematically contain most binary natural amino acid side chain combinations, the data also provide insight into the promiscuity of each S100 protein towards all potential naturally occurring S100 partners in the human proteome. Such information will be precious for future drug design to interfere with S100 related pathologies.


Assuntos
Motivos EF Hand , Proteínas S100 , Proteínas de Ligação ao Cálcio/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Proteínas S100/metabolismo
14.
Nat Med ; 7(1): 108-13, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11135624

RESUMO

Diabetic patients frequently suffer from retinopathy, nephropathy, neuropathy and accelerated atherosclerosis. The loss of endothelial function precedes these vascular alterations. Here we report that activation of poly(ADP-ribose) polymerase (PARP) is an important factor in the pathogenesis of endothelial dysfunction in diabetes. Destruction of islet cells with streptozotocin in mice induced hyperglycemia, intravascular oxidant production, DNA strand breakage, PARP activation and a selective loss of endothelium-dependent vasodilation. Treatment with a novel potent PARP inhibitor, starting after the time of islet destruction, maintained normal vascular responsiveness, despite the persistence of severe hyperglycemia. Endothelial cells incubated in high glucose exhibited production of reactive nitrogen and oxygen species, consequent single-strand DNA breakage, PARP activation and associated metabolic and functional impairment. Basal and high-glucose-induced nuclear factor-kappaB activation were suppressed in the PARP-deficient cells. Our results indicate that PARP may be a novel drug target for the therapy of diabetic endothelial dysfunction.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Endotélio Vascular/fisiopatologia , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , Diabetes Mellitus Experimental/enzimologia , Endotélio Vascular/enzimologia , Ativação Enzimática , Glucose/farmacologia , Imuno-Histoquímica , Técnicas In Vitro , Camundongos , NF-kappa B/metabolismo
15.
Nephron Clin Pract ; 117(4): c373-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21071961

RESUMO

BACKGROUND: Resistance to erythropoiesis-stimulating agents (ESAs) has been observed in patients with chronic kidney disease (CKD) and it is associated with clinical outcomes. The presence of ESA resistance cannot always be explained by the known risk factors of the condition, suggesting that additional factors may be involved. We wanted to test the hypothesis that vitamin D insufficiency is associated with lower hemoglobin (Hb) and ESA resistance in patients on maintenance hemodialysis (HD). METHODS: Data from patients receiving maintenance HD in a single dialysis center were extracted from the medical records in a retrospective chart review. Basic patient characteristics and laboratory data including Hb, serum albumin, intact parathyroid hormone and serum 25(OH)-cholecalciferol (25(OH)D(3)) levels were collected. ESA dose and Kt/V were extracted from the dialysis charts. Correlation analysis and multivariate linear regression analysis were used to reveal potential independent associations between clinical and laboratory parameters and ESA resistance. RESULTS: Data from 142 patients were analyzed. Serum 25(OH)D(3) concentration was significantly correlated with Hb (ρ = 0.186, p < 0.05) and also with ESA dose/Hb index (ρ = 0.230, p < 0.01). In multivariable regression analyses, serum 25(OH)D(3) concentration remained significantly associated with both Hb and ESA dose/Hb index after controlling for potentially important confounders. CONCLUSION: Serum 25(OH)D(3) concentration is independently associated with erythropoietin responsiveness in CKD patients on maintenance HD. If this association will be confirmed, treatment trials looking at the effect of vitamin D supplementation on anemia treatment in CKD patients may be warranted.


Assuntos
Calcifediol/sangue , Hematínicos/uso terapêutico , Hemoglobinas/metabolismo , Falência Renal Crônica/sangue , Diálise Renal , Adulto , Idoso , Biomarcadores/sangue , Estudos Transversais , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico
16.
Methods Mol Biol ; 2256: 179-192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34014523

RESUMO

The dynamic regulation of protein-protein interactions (PPIs) involves phosphorylation of short liner motifs in disordered protein regions modulating binding affinities. The ribosomal-S6-kinase 1 is capable of binding to scaffold proteins containing PDZ domains through a PDZ-binding motif (PBM) located at the disordered C-terminus of the kinase. Phosphorylation of the PBM dramatically changes the interactome of RSK1 with PDZ domains exerting a fine-tuning mechanism to regulate PPIs. Here we present in detail highly effective biophysical (fluorescence polarization, isothermal calorimetry) and cellular (protein-fragment complementation) methods to study the effect of phosphorylation on RSK1-PDZ interactions that can be also applied to investigate phosphoregulation of other PPIs in signaling pathways.


Assuntos
Polarização de Fluorescência/métodos , Proteínas Associadas aos Microtúbulos/metabolismo , Domínios PDZ , Domínios e Motivos de Interação entre Proteínas , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Sítios de Ligação , Humanos , Fosforilação , Ligação Proteica , Transdução de Sinais
17.
Elife ; 102021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34870594

RESUMO

The phosphorylation-activated anion channel cystic fibrosis transmembrane conductance regulator (CFTR) is gated by an ATP hydrolysis cycle at its two cytosolic nucleotide-binding domains, and is essential for epithelial salt-water transport. A large number of CFTR mutations cause cystic fibrosis. Since recent breakthrough in targeted pharmacotherapy, CFTR mutants with impaired gating are candidates for stimulation by potentiator drugs. Thus, understanding the molecular pathology of individual mutations has become important. The relatively common R117H mutation affects an extracellular loop, but nevertheless causes a strong gating defect. Here, we identify a hydrogen bond between the side chain of arginine 117 and the backbone carbonyl group of glutamate 1124 in the cryo-electronmicroscopic structure of phosphorylated, ATP-bound CFTR. We address the functional relevance of that interaction for CFTR gating using macroscopic and microscopic inside-out patch-clamp recordings. Employing thermodynamic double-mutant cycles, we systematically track gating-state-dependent changes in the strength of the R117-E1124 interaction. We find that the H-bond is formed only in the open state, but neither in the short-lived 'flickery' nor in the long-lived 'interburst' closed state. Loss of this H-bond explains the strong gating phenotype of the R117H mutant, including robustly shortened burst durations and strongly reduced intraburst open probability. The findings may help targeted potentiator design.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/genética , Fibrose Cística/fisiopatologia , Ligação de Hidrogênio , Patologia Molecular , Humanos , Mutação
18.
Antibiotics (Basel) ; 10(12)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34943721

RESUMO

Perioperative antibiotic use is a common reason for antibiotic misuse. Evidence suggests that adherence to SAP guidelines may improve outcomes. The purpose of this study was to analyze the impact of pharmacist-led antibiotic stewardship interventions on SAP guideline compliance. The study was conducted at an Orthopedic Department of a tertiary care medical center. SAP compliance and antibiotic exposure in the pre-intervention and intervention period was compared using chi-square, Fisher exact, and Mann-Whitney tests, as appropriate. Prophylactic antibiotic use in orthopedic joint arthroplasties (overall guideline adherence: agent, dose, frequency, duration), clinical outcomes (length of stay-LOS, number of surgical site infections-SSIs), antibiotic exposure and direct antibiotic costs were compared between pre-intervention and intervention periods. Significant improvement in mean SAP duration (by 42.9%, 4.08 ± 2.08 vs. 2.08 ± 1.90 days, p ˂ 0.001), and overall guideline adherence regarding antibiotic use (by 56.2%, from 2% to 58.2%, p ˂ 0.001) were observed. A significant decrease was observed in antibiotic exposure in SAP (by 41%, from 6.07 ± 0.05 to 3.58 ± 4.33 DDD/patient, p ˂ 0.001), average prophylactic antibiotic cost (by 54.8%, 9278.79 ± 6094.29 vs. 3598.16 ± 3354.55 HUF/patient), and mean LOS (by 37.2%, from 11.22 ± 6.96 to 7.62 ± 3.02 days, p < 0.001); and a slight decrease in the number of confirmed SSIs was found between the two periods (by 1.8%, from 3% to 1.2%, p = 0.21). Continuous presence of the clinical pharmacist led to significant improvement in SAP guideline adherence, which was accompanied by decreased antibiotic exposure and cost.

19.
J Steroid Biochem Mol Biol ; 211: 105904, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33933576

RESUMO

One of the main directions of steroid research is the preparation of modified derivatives in which, in addition to changes in physicochemical properties, receptor binding is significantly altered, thus a bioactivity different from that of the parent compound predominates. In the frame of this work, 2-arylidene derivatives were first synthesized by regioselective modification of the A-ring of natural sex hormone, 5α-dihydrotestosterone (DHT). After Claisen-Schmidt condensations of DHT with (hetero)aromatic aldehydes in alkaline EtOH, heterocyclizations of the α,ß-enones were performed with 3-amino-1,2,4-triazole, 3-aminopyrazole and 3-amino-5-methylpyrazole in the presence of t-BuOK in DMF to afford 7'-epimeric mixtures of A-ring-fused azolo-dihydropyrimidines, respectively. Depending on the electronic demand of the substituents of the arylidene moiety, spontaneous or 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ)-induced oxidation of the heteroring led to triazolo[1,5-a]pyrimidines and pyrazolo[1,5-a]pyrimidines in good yields, while, using the Jones reagent as a strong oxidant, 17-oxidation also occurred. The crystal structures of an arylidene and a triazolopyrimidine product have been determined by single crystal X-ray diffraction and both were found to crystallize in the monoclinic crystal system at P21 space group. Most derivatives were found to diminish the transcriptional activity of androgen receptor (AR) in reporter cell line. The candidate compound (17ß-hydroxy-2-(4-chloro)benzylidene-5α-androstan-3-one, 2f) showed to suppress androgen-mediated AR transactivation in a dose-dependent manner. We confirmed the cellular interaction of 2f with AR, described the binding in AR-binding cavity by the flexible docking and showed the ability of the compound to suppress the expression of AR-regulated genes in two prostate cancer cell lines.


Assuntos
Antagonistas de Receptores de Andrógenos/síntese química , Antagonistas de Receptores de Andrógenos/farmacologia , Di-Hidrotestosterona/química , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Sobrevivência Celular , Humanos , Masculino , Conformação Molecular , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
20.
J Inorg Biochem ; 220: 111468, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33951554

RESUMO

The solution chemical properties such as proton dissociation, complex formation with copper(II) and gallium(III) ions in addition to antibacterial and antitumor activity of a novel tridentate salicyaldehyde semicarbazone-estrone hybrid (estrone-SC) and a related bicyclic compound (thn-SC) were investigated. The crystal structure of complex [Cu(thn-SCH-1)Cl] was studied by single crystal X-ray diffraction method. Estrone-SC and thn-SC form mono-ligand complexes with Cu(II) characterized by relatively high stability, however, they are much less stable than their thiosemicarbazone analogues. The neutral Cu(II) complexes with (O-,N,O-)(H2O) coordination mode predominate at physiological pH. Estrone-SC and thn-SC are more efficient Ga(III) binders in comparison with thiosemicarbazones, although the complexes also suffer dissociation at pH 7.4. The Cu(II) complex of estrone-SC displayed significant cytotoxicity in A549, SW480 and CH1/PA cancer cells, and moderate apoptosis induction and ROS formation. The semicarbazone compounds did not exhibit antibacterial effect; unlike the related Cu(II)-thiosemicarbazone complexes represented by the fairly low MIC values (3-50 µM) obtained on the Gram-positive Staphylococcus aureus and Enterococcus faecalis bacteria.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Estrona/análogos & derivados , Estrona/farmacologia , Semicarbazonas/farmacologia , Antibacterianos/síntese química , Antineoplásicos/síntese química , Ácido Ascórbico/química , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Cobre/química , Ensaios de Seleção de Medicamentos Antitumorais , Gálio/química , Glutationa/química , Humanos , Ligantes , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Semicarbazonas/síntese química
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