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1.
PeerJ ; 12: e17086, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500530

RESUMO

Circadian rhythms in honey bees are involved in various processes that impact colony survival. For example, young nurses take care of the brood constantly throughout the day and lack circadian rhythms. At the same time, foragers use the circadian clock to remember and predict food availability in subsequent days. Previous studies exploring the ontogeny of circadian rhythms of workers showed that the onset of rhythms is faster in the colony environment (~2 days) than if workers were immediately isolated after eclosion (7-9 days). However, which specific environmental factors influenced the early development of worker circadian rhythms remained unknown. We hypothesized that brood nest temperature plays a key role in the development of circadian rhythmicity in young workers. Our results show that young workers kept at brood nest-like temperatures (33-35 °C) in the laboratory develop circadian rhythms faster and in greater proportion than bees kept at lower temperatures (24-26 °C). In addition, we examined if the effect of colony temperature during the first 48 h after emergence is sufficient to increase the rate and proportion of development of circadian rhythmicity. We observed that twice as many individuals exposed to 35 °C during the first 48 h developed circadian rhythms compared to individuals kept at 25 °C, suggesting a critical developmental period where brood nest temperatures are important for the development of the circadian system. Together, our findings show that temperature, which is socially regulated inside the hive, is a key factor that influences the ontogeny of circadian rhythmicity of workers.


Assuntos
Relógios Circadianos , Comportamento Social , Humanos , Abelhas , Animais , Temperatura , Ritmo Circadiano
2.
Sensors (Basel) ; 23(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38067753

RESUMO

Pedestrian detection based on deep learning methods have reached great success in the past few years with several possible real-world applications including autonomous driving, robotic navigation, and video surveillance. In this work, a new neural network two-stage pedestrian detector with a new custom classification head, adding the triplet loss function to the standard bounding box regression and classification losses, is presented. This aims to improve the domain generalization capabilities of existing pedestrian detectors, by explicitly maximizing inter-class distance and minimizing intra-class distance. Triplet loss is applied to the features generated by the region proposal network, aimed at clustering together pedestrian samples in the features space. We used Faster R-CNN and Cascade R-CNN with the HRNet backbone pre-trained on ImageNet, changing the standard classification head for Faster R-CNN, and changing one of the three heads for Cascade R-CNN. The best results were obtained using a progressive training pipeline, starting from a dataset that is further away from the target domain, and progressively fine-tuning on datasets closer to the target domain. We obtained state-of-the-art results, MR-2 of 9.9, 11.0, and 36.2 for the reasonable, small, and heavy subsets on the CityPersons benchmark with outstanding performance on the heavy subset, the most difficult one.

3.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 34(6): 273-282, nov.- dec. 2023. tab
Artigo em Inglês | IBECS | ID: ibc-227206

RESUMO

Purpose of the study A prospective, randomized, double-blind study was designed to assess differences in brain relaxation between 20% mannitol and 3% hypertonic saline (HS) during elective supratentorial brain tumour surgery in patients with midline shift. Material and methods Sixty patients undergoing supratentorial craniotomy for tumour resection were enrolled to receive either 5mL/kg of 20% mannitol (n=30) or 3% HS (n=30) administered at skin incision. PCO2 in arterial blood was maintained within 35–40mmHg and arterial blood pressure was controlled within baseline values ±20%. The primary outcome was the proportion of satisfactory brain relaxation. The surgeon assessed brain relaxation on a four-point scale (1=excellent with no swelling, 2=minimal swelling, 3=serious swelling not requiring treatment, 4=severe swelling requiring treatment). Postsurgical intracranial changes determined by imaging techniques, postoperative complications, PACU and hospital stay, and mortality at 30 days were also recorded. Appropriate statistical tests were used for comparison; P<0.05 was considered as significant. This trial was registered in Eudract.ema.europa.eu (#2021-006290-40). Results There was no difference in brain relaxation: 2.00 [1.00–2.00] and 2.00 [1.75–3.00] for patients in mannitol and HS groups, respectively (P=0.804). Tumour size (OR: 0.99, 95% CI: 0.99–1.01; P=0.371), peritumoral oedema classification (OR: 0.57, 95% CI: 0.11–2.84; P=0.493), mass effect (OR: 0.86, 95% CI: 0.16–4.87; P=0.864), anaesthesia (OR: 4.88, 95% CI: 0.82–28.96; P=0.081) and midline shift (OR: 5.00, 95% CI: 0.84–29.70; P=0.077) did not have a significant influence on brain swelling in patients treated with either mannitol or HS. No significant differences in perioperative outcomes, mortality and length of PACU and hospital stay were observed (AU)


Objetivos del estudio Estudio prospectivo, aleatorizado y doble ciego diseñado para evaluar diferencias en la relajación cerebral entre manitol 20% y salino hipertónico (SH) 3% durante cirugía supratentorial electiva por tumor cerebral en pacientes con desviación de línea media. Material y métodos Sesenta pacientes sometidos a craneotomía supratentorial para resección tumoral se estudiaron para recibir 5ml/kg de manitol 20% (n=30) o SH 3% (n=30) administrados durante la incisión cutánea. La pCO2 en sangre arterial se mantuvo entre 35-40mmHg y la presión arterial se controló dentro de valores basales±20%. El objetivo principal fue la proporción de relajación cerebral satisfactoria. El cirujano evaluó la relajación cerebral en una escala de 4 puntos (1=excelente sin hinchazón, 2=hinchazón mínima, 3=hinchazón grave que no requiere tratamiento, 4=hinchazón severa que requiere tratamiento). Los cambios intracraneales posquirúrgicos determinados por técnicas de imagen, complicaciones postoperatorias, estancia en reanimación y hospitalaria, así como mortalidad a 30 días fueron registrados. Se usaron test estadísticos para la comparación, siendo considerado p<0,05 como significativo. El ensayo fue registrado en Eudract.ema.europa.eu (#2021-006290-40). Resultados No hubo diferencias en la relajación cerebral: 2,00 [1,00-2,00] y 2,00 [1,75-3,00] en los pacientes del grupo manitol y SH respectivamente (p=0,804). El tamaño tumoral (OR: 0,99: IC 95%:0,99-1,01; p=0,371), nivel de edema peritumoral (OR: 0,57; IC 95%:0,11-2,84; p=0,493), efecto masa (OR: 0,86; IC 95%: 0,16-4,87; p=0,864), anestesia empleada (OR: 4,88; 95% IC: 0,82-28,96; p=0,081) y desviación de la línea media (OR: 5,00; IC 95%: 0,84-29,70; p=0,077) no tuvieron influencia significativa sobre la hinchazón cerebral en los pacientes de ambos grupos. No hubo diferencias significativas en los resultados perioperatorios, mortalidad ni en estancia en reanimación ni hospitalaria (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Diuréticos Osmóticos/uso terapêutico , Solução Salina Hipertônica/uso terapêutico , Neoplasias Supratentoriais/cirurgia , Craniotomia/métodos , Manitol/uso terapêutico , Estudos Prospectivos
4.
Nature ; 623(7989): 1070-1078, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37968394

RESUMO

Three billion years of evolution has produced a tremendous diversity of protein molecules1, but the full potential of proteins is likely to be much greater. Accessing this potential has been challenging for both computation and experiments because the space of possible protein molecules is much larger than the space of those likely to have functions. Here we introduce Chroma, a generative model for proteins and protein complexes that can directly sample novel protein structures and sequences, and that can be conditioned to steer the generative process towards desired properties and functions. To enable this, we introduce a diffusion process that respects the conformational statistics of polymer ensembles, an efficient neural architecture for molecular systems that enables long-range reasoning with sub-quadratic scaling, layers for efficiently synthesizing three-dimensional structures of proteins from predicted inter-residue geometries and a general low-temperature sampling algorithm for diffusion models. Chroma achieves protein design as Bayesian inference under external constraints, which can involve symmetries, substructure, shape, semantics and even natural-language prompts. The experimental characterization of 310 proteins shows that sampling from Chroma results in proteins that are highly expressed, fold and have favourable biophysical properties. The crystal structures of two designed proteins exhibit atomistic agreement with Chroma samples (a backbone root-mean-square deviation of around 1.0 Å). With this unified approach to protein design, we hope to accelerate the programming of protein matter to benefit human health, materials science and synthetic biology.


Assuntos
Algoritmos , Simulação por Computador , Conformação Proteica , Proteínas , Humanos , Teorema de Bayes , Evolução Molecular Direcionada , Aprendizado de Máquina , Modelos Moleculares , Dobramento de Proteína , Proteínas/química , Proteínas/metabolismo , Semântica , Biologia Sintética/métodos , Biologia Sintética/tendências
5.
Gels ; 9(11)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37998999

RESUMO

This research explores the integration of DUT-67 metal organic frameworks into polyethyleneimine-based hydrogels to assemble a composite system with enough mechanical strength, pore structure and chemical affinity to work as a sorbent for water remediation. By varying the solvent-to-modulator ratio in a water-based synthesis path, the particle size of DUT-67 was successfully modulated from 1 µm to 200 nm. Once DUT-67 particles were integrated into the polymeric hydrogel, the composite hydrogel exhibited enhanced mechanical properties after the incorporation of the MOF filler. XPS, NMR, TGA, FTIR, and FT Raman studies confirmed the presence and interaction of the DUT-67 particles with the polymeric chains within the hydrogel network. Adsorption studies of methyl orange, copper(II) ions, and penicillin V on the composite hydrogel revealed a rapid adsorption kinetics and monolayer adsorption according to the Langmuir's model. The composite hydrogel demonstrated higher adsorption capacities, as compared to the pristine hydrogel, showcasing a synergistic effect, with maximum adsorption capacities of 473 ± 21 mg L-1, 86 ± 6 mg L-1, and 127 ± 4 mg L-1, for methyl orange, copper(II) ions, and penicillin V, respectively. This study highlights the potential of MOF-based composite hydrogels as efficient adsorbents for environmental pollutants and pharmaceuticals.

6.
Front Cell Dev Biol ; 11: 1122408, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799272

RESUMO

Introduction: Cardiac fibroblasts (CF) are crucial cells in damaged heart tissues, expressing TLR4, IFN-receptor and responding to lipopolysaccharide (LPS) and interferon-ß (IFN-ß) respectively. While CF interact with immune cells; however, their relationship with neutrophils remains understudied. Additionally, theimpact of LPS and IFN-ß on CF-neutrophil interaction is poorly understood. Methods: Isolated CF from adult rats were treated with LPS, with or without IFN-ß. This study examined IL-8 secretion, ICAM-1 and VCAM-1 expression, and neutrophil recruitment, as well as their effects on MMPs activity. Results: LPS triggered increased IL-8 expression and secretion, along with elevated ICAM-1 and VCAM-1 expression, all of which were blocked by TAK-242. Pre-treatment with IFN-ß countered these LPS effects. LPS treated CF showed higher neutrophil recruitment (migration and adhesion) compared to unstimulated CF, an effect prevented by IFN-ß. Ruxolitinib blocked these IFN-ß anti-inflammatory effects, implicating JAK signaling. Analysis of culture medium zymograms from CF alone, and CF-neutrophils interaction, revealed that MMP2 was mainly originated from CF, while MMP9 could come from neutrophils. LPS and IFN-ß boosted MMP2 secretion by CF. MMP9 activity in CF was low, and LPS or IFN-ß had no significant impact. Pre-treating CF with LPS, IFN-ß, or both before co-culture with neutrophils increased MMP2. Neutrophil co-culture increased MMP9 activity, with IFN-ß pre-treatment reducing MMP9 compared to unstimulated CF. Conclusion: In CF, LPS induces the secretion of IL-8 favoring neutrophils recruitment and these effects were blocked by IFN-. The results highlight that CF-neutrophil interaction appears to influence the extracellular matrix through MMPs activity modulation.

7.
Elife ; 122023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37432316

RESUMO

Ubiquitin-proteasome system (UPS) dysfunction is associated with the pathology of a wide range of human diseases, including myopathies and muscular atrophy. However, the mechanistic understanding of specific components of the regulation of protein turnover during development and disease progression in skeletal muscle is unclear. Mutations in KLHL40, an E3 ubiquitin ligase cullin3 (CUL3) substrate-specific adapter protein, result in severe congenital nemaline myopathy, but the events that initiate the pathology and the mechanism through which it becomes pervasive remain poorly understood. To characterize the KLHL40-regulated ubiquitin-modified proteome during skeletal muscle development and disease onset, we used global, quantitative mass spectrometry-based ubiquitylome and global proteome analyses of klhl40a mutant zebrafish during disease progression. Global proteomics during skeletal muscle development revealed extensive remodeling of functional modules linked with sarcomere formation, energy, biosynthetic metabolic processes, and vesicle trafficking. Combined analysis of klh40 mutant muscle proteome and ubiquitylome identified thin filament proteins, metabolic enzymes, and ER-Golgi vesicle trafficking pathway proteins regulated by ubiquitylation during muscle development. Our studies identified a role for KLHL40 as a regulator of ER-Golgi anterograde trafficking through ubiquitin-mediated protein degradation of secretion-associated Ras-related GTPase1a (Sar1a). In KLHL40-deficient muscle, defects in ER exit site vesicle formation and downstream transport of extracellular cargo proteins result in structural and functional abnormalities. Our work reveals that the muscle proteome is dynamically fine-tuned by ubiquitylation to regulate skeletal muscle development and uncovers new disease mechanisms for therapeutic development in patients.


Assuntos
Proteínas Musculares , Peixe-Zebra , Animais , Humanos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Peixe-Zebra/metabolismo , Proteoma/metabolismo , Músculo Esquelético/metabolismo , Ubiquitinação , Sarcômeros/metabolismo , Ubiquitina/metabolismo , Retículo Endoplasmático/metabolismo , Desenvolvimento Muscular , Progressão da Doença
8.
BMC Pregnancy Childbirth ; 23(1): 469, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353749

RESUMO

BACKGROUND: Early prediction of Gestational Diabetes Mellitus (GDM) risk is of particular importance as it may enable more efficacious interventions and reduce cumulative injury to mother and fetus. The aim of this study is to develop machine learning (ML) models, for the early prediction of GDM using widely available variables, facilitating early intervention, and making possible to apply the prediction models in places where there is no access to more complex examinations. METHODS: The dataset used in this study includes registries from 1,611 pregnancies. Twelve different ML models and their hyperparameters were optimized to achieve early and high prediction performance of GDM. A data augmentation method was used in training to improve prediction results. Three methods were used to select the most relevant variables for GDM prediction. After training, the models ranked with the highest Area under the Receiver Operating Characteristic Curve (AUCROC), were assessed on the validation set. Models with the best results were assessed in the test set as a measure of generalization performance. RESULTS: Our method allows identifying many possible models for various levels of sensitivity and specificity. Four models achieved a high sensitivity of 0.82, a specificity in the range 0.72-0.74, accuracy between 0.73-0.75, and AUCROC of 0.81. These models required between 7 and 12 input variables. Another possible choice could be a model with sensitivity of 0.89 that requires just 5 variables reaching an accuracy of 0.65, a specificity of 0.62, and AUCROC of 0.82. CONCLUSIONS: The principal findings of our study are: Early prediction of GDM within early stages of pregnancy using regular examinations/exams; the development and optimization of twelve different ML models and their hyperparameters to achieve the highest prediction performance; a novel data augmentation method is proposed to allow reaching excellent GDM prediction results with various models.


Assuntos
Diabetes Gestacional , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Curva ROC , Aprendizado de Máquina
9.
J Mol Biol ; 435(8): 168038, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36889459

RESUMO

The human ATP-binding cassette (ABC) transporter ABCA1 plays a critical role in lipid homeostasis as it extracts sterols and phospholipids from the plasma membrane for excretion to the extracellular apolipoprotein A-I and subsequent formation of high-density lipoprotein (HDL) particles. Deleterious mutations of ABCA1 lead to sterol accumulation and are associated with atherosclerosis, poor cardiovascular outcomes, cancer, and Alzheimer's disease. The mechanism by which ABCA1 drives lipid movement is poorly understood, and a unified platform to produce active ABCA1 protein for both functional and structural studies has been missing. In this work, we established a stable expression system for both a human cell-based sterol export assay and protein purification for in vitro biochemical and structural studies. ABCA1 produced in this system was active in sterol export and displayed enhanced ATPase activity after reconstitution into a lipid bilayer. Our single-particle cryo-EM study of ABCA1 in nanodiscs showed protein induced membrane curvature, revealed multiple distinct conformations, and generated a structure of nanodisc-embedded ABCA1 at 4.0-Å resolution representing a previously unknown conformation. Comparison of different ABCA1 structures and molecular dynamics simulations demonstrates both concerted domain movements and conformational variations within each domain. Taken together, our platform for producing and characterizing ABCA1 in a lipid membrane enabled us to gain important mechanistic and structural insights and paves the way for investigating modulators that target the functions of ABCA1.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Membrana Celular , Lipídeos de Membrana , Imagem Individual de Molécula , Esteróis , Humanos , Apolipoproteína A-I/metabolismo , Transportador 1 de Cassete de Ligação de ATP/química , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membrana Celular/química , Fosfolipídeos/química , Esteróis/química , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Mutação , Bicamadas Lipídicas/química , Imagem Individual de Molécula/métodos
10.
Neurocirugia (Astur : Engl Ed) ; 34(6): 273-282, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36931929

RESUMO

PURPOSE OF THE STUDY: A prospective, randomized, double-blind study was designed to assess differences in brain relaxation between 20% mannitol and 3% hypertonic saline (HS) during elective supratentorial brain tumour surgery in patients with midline shift. MATERIAL AND METHODS: Sixty patients undergoing supratentorial craniotomy for tumour resection were enrolled to receive either 5mL/kg of 20% mannitol (n=30) or 3% HS (n=30) administered at skin incision. PCO2 in arterial blood was maintained within 35-40mmHg and arterial blood pressure was controlled within baseline values ±20%. The primary outcome was the proportion of satisfactory brain relaxation. The surgeon assessed brain relaxation on a four-point scale (1=excellent with no swelling, 2=minimal swelling, 3=serious swelling not requiring treatment, 4=severe swelling requiring treatment). Postsurgical intracranial changes determined by imaging techniques, postoperative complications, PACU and hospital stay, and mortality at 30 days were also recorded. Appropriate statistical tests were used for comparison; P<0.05 was considered as significant. This trial was registered in Eudract.ema.europa.eu (#2021-006290-40). RESULTS: There was no difference in brain relaxation: 2.00 [1.00-2.00] and 2.00 [1.75-3.00] for patients in mannitol and HS groups, respectively (P=0.804). Tumour size (OR: 0.99, 95% CI: 0.99-1.01; P=0.371), peritumoral oedema classification (OR: 0.57, 95% CI: 0.11-2.84; P=0.493), mass effect (OR: 0.86, 95% CI: 0.16-4.87; P=0.864), anaesthesia (OR: 4.88, 95% CI: 0.82-28.96; P=0.081) and midline shift (OR: 5.00, 95% CI: 0.84-29.70; P=0.077) did not have a significant influence on brain swelling in patients treated with either mannitol or HS. No significant differences in perioperative outcomes, mortality and length of PACU and hospital stay were observed. CONCLUSIONS: 5mL/kg of 20% mannitol or 3% HS result in similar brain relaxation scores in patients undergoing craniotomy for supratentorial brain tumour with midline shift.


Assuntos
Neoplasias Encefálicas , Neoplasias Supratentoriais , Humanos , Neoplasias Encefálicas/cirurgia , Craniotomia/efeitos adversos , Manitol/uso terapêutico , Estudos Prospectivos , Solução Salina Hipertônica/uso terapêutico , Neoplasias Supratentoriais/cirurgia
11.
Biomedicines ; 11(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36831113

RESUMO

The leading cause of death in psoriasis is cardiovascular disease. The determinants that induce the increase in this risk are not known. The systemic inflammatory process is dependent on lymphocytes and monocytes, as has been proposed. However, adaptation modules such as mTOR have recently been mentioned as having a role. Other factors, such as WNT and its non-canonical WNT5a-inducing pathway, are relevant in inflammation, cell migration, and neoangiogenesis. Thus, we studied circulating monocytes from untreated severe psoriatic patients and characterized inflammatory cytokines, chemokines, mTOR activity, and the cardiovascular risk marker ADAMTS7. Peripheral blood from ten severely psoriatic patients (Psoriasis severity index greater than 10) was extracted and age- and sex-matched with healthy subjects. Surface and intracellular flow cytometry were performed for cytokine, chemokine receptors, and mTOR activity. ADAMTS7 was measured using ELISA. Psoriatic patients had a higher frequency of WNT5a+ cells in monocytes, which also had higher levels of IL-1ß, IL-6, CXCR3, CCR2, and phosphorylated S6R protein. We found that M1 monocytes are dominant in the WNT5a+ cell group, and intracellular levels of WNT5a were also augmented. Levels of WNT5a were correlated with ADAMTS7, a blood marker related to the pathogenesis of atheromatosis. WNT5a could be relevant to the cardiovascular risk of psoriatic patients considering its association with higher levels of inflammatory cytokines, chemokine receptors and the pro-atherogenic profile of circulating monocytes.

12.
Metabolites ; 13(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36677041

RESUMO

Psoriasis is a skin disease with occasional involvement of non-cutaneous territories. Beyond the usual, cardiovascular events are more frequent in these patients and correlate only partially with disease activity, suggesting the presence of other unknown factors. We selected ten psoriatic patients without treatment in the last year and matched them for age and gender with eleven healthy subjects. Ficoll-extracted mononuclear cells were analyzed with flow cytometry for monocyte surface phenotype markers, intracellular NFκB/inflammasome-dependent interleukins, and chemotaxis receptor CXCR3. Using ELISA, patient serum was evaluated for ADAMTS7 and CXCL10. Inflammatory M1 monocytes showed higher levels of IL-1ß and IL-6 in psoriatic patients. M2 monocytes also showed higher levels of intracellular inflammatory cytokines. Nevertheless, IL-6 values were higher compared to other monocytes and IL-1ß. The mTORC activation markers ADAMTS7 and S6Rp were higher in psoriatic patients than in healthy controls. In psoriatic patients, serum levels of ADAMTS7 were elevated, and M2 monocytes showed a distinct inflammatory response with higher relative levels of NFκB-dependent IL-6 and less activity of the CXCR3-CXCL10 chemotactic pathway. These data suggest pathways with potential markers for prediction and early detection of cardiovascular risk in psoriatic patients.

13.
Biochim Biophys Acta Mol Basis Dis ; 1869(4): 166642, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36669578

RESUMO

Cardiac fibroblasts are a cell population that controls the homeostasis of the extracellular matrix and orchestrates a damage response to maintain cardiac architecture and performance. Due to these functions, fibroblasts play a central role in cardiac fibrosis development, and there are large differences in matrix protein secretion profiles between fibroblasts from aged versus young animals. Senescence is a multifactorial and complex process that has been associated with inflammatory and fibrotic responses. After damage, transient cellular senescence is usually beneficial, as these cells promote tissue repair. However, the persistent presence of senescent cells within a tissue is linked with fibrosis development and organ dysfunction, leading to aging-related diseases such as cardiovascular pathologies. In the heart, early cardiac fibroblast senescence after myocardial infarction seems to be protective to avoid excessive fibrosis; however, in non-infarcted models of cardiac fibrosis, cardiac fibroblast senescence has been shown to be deleterious. Today, two new classes of drugs, termed senolytics and senostatics, which eliminate senescent cells or modify senescence-associated secretory phenotype, respectively, arise as novel therapeutical strategies to treat aging-related pathologies. However, further studies will be needed to evaluate the extent of the utility of senotherapeutic drugs in cardiac diseases, in which pathological context and temporality of the intervention must be considered.


Assuntos
Senescência Celular , Coração , Animais , Senescência Celular/fisiologia , Envelhecimento/patologia , Fibrose , Fibroblastos/metabolismo
14.
Biochim Biophys Acta Mol Basis Dis ; 1868(11): 166525, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987478

RESUMO

Cardiac fibroblasts (CFs) undergo senescence in reaction to different stressors, leading to a poor prognosis of cardiac disease. Doxorubicin (Doxo) is an antineoplastic drug with strong cardiotoxic effects, which induces IL-1ß secretion and thus, triggers a potent pro-inflammatory response. Doxo induces CFs senescence; however, the mechanisms are not fully understood. Different pharmacological strategies have been used to eliminate senescent cells by inducing their apoptosis or modifying their secretome. However, Resolvin E1 (RvE1), a lipid derivative resolutive mediator with potent anti-inflammatory effects has not been used before to prevent CFs senescence. CFs were isolated from adult male C57BL/6J mice and subsequently stimulated with Doxo, in the presence or absence of RvE1. Senescence-associated ß-galactosidase activity (SA-ß-gal), γ-H2A.X, p53, p21, and senescence-associated secretory phenotype (SASP) were evaluated. The involvement of the NLRP3 inflammasome/interleukin-1 receptor (IL-1R) signaling pathway on CFs senescence was studied using an NLRP3 inhibitor (MCC950) and an endogenous IL-1R antagonist (IR1A). Doxo is able to trigger CFs senescence, as evidenced by an increase of γ-H2A.X, p53, p21, and SA-ß-gal, and changes in the SASP profile. These Doxo effects were prevented by RvE1. Doxo triggers IL-1ß secretion, which was dependent on NLRP3 activation. Doxo-induced CFs senescence was partially blocked by MCC950 and IR1A. In addition, IL-1ß also triggered CFs senescence, as evidenced by the increase of γ-H2A.X, p53, p21, SA-ß-gal activity, and SASP. All these effects were also prevented by RvE1 treatment. CONCLUSION: These data show the anti-senescent role of RvE1 in Doxo-induced CFs senescence, which could be mediated by reducing IL-1ß secretion.


Assuntos
Inflamassomos , Interleucina-1beta/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Senescência Celular , Doxorrubicina/farmacologia , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/farmacologia , Fibroblastos/metabolismo , Furanos , Indenos , Inflamassomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptores de Interleucina-1/metabolismo , Sulfonamidas , Proteína Supressora de Tumor p53/metabolismo , beta-Galactosidase/metabolismo , beta-Galactosidase/farmacologia
15.
Inflammation ; 45(6): 2498-2512, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35867264

RESUMO

Angiotensin II (Ang-II) is a widely studied hypertensive, profibrotic, and pro-inflammatory peptide. In the heart, cardiac fibroblasts (CF) express type 1 angiotensin II receptors (AT1R), Toll-like receptor-4 (TLR4), and the NLRP3 inflammasome complex, which play important roles in pro-inflammatory processes. When activated, the NLRP3 inflammasome triggers proteolytic cleavage of pro-IL-1, resulting in its activation. However, in CF the mechanism by which Ang-II assembles and activates the NLRP3 inflammasome remains not fully known. To elucidate this important point, we stimulated TLR4 receptors in CF and evaluated the signaling pathways by which Ang-II triggers the assembly and activity. In cultured rat CF, pro-IL-1ß levels, NLRP3, ASC, and caspase-1 expression levels were determined by Western blot. NLRP3 inflammasome complex assembly was analyzed by immunocytochemistry, whereas by ELISA, we analyzed NLRP3 inflammasome activity and [Formula: see text] release. In CF, Ang-II triggered NLRP3 inflammasome assembly and caspase-1 activity; and in LPS-pretreated CF, Ang-II also triggered [Formula: see text] secretion. These effects were blocked by losartan (AT1R antagonist), U73221 (PLC inhibitor), 2-APB (IP3R antagonist), and BAPTA-AM (Ca2+ chelator) indicating that the AT1R/PLC/IP3R/Ca2+ pathway is involved. Finally, bafilomycin A1 prevented Ang-II-induced [Formula: see text] secretion, indicating that a non-classical protein secretion mechanism is involved. These findings suggest that in CF, Ang-II by a Ca2+-dependent mechanism triggers NLRP3 inflammasome assembly and activation leading to [Formula: see text] secretion through a non-conventional protein secretion mechanism.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Angiotensina II/farmacologia , Receptor 4 Toll-Like , Interleucina-1beta/metabolismo , Caspase 1/metabolismo , Fibroblastos/metabolismo
16.
Antibiotics (Basel) ; 10(11)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34827358

RESUMO

Wounds represent a major healthcare problem especially in hospital-associated infections where multi-drug resistant strains are often involved. Nowadays, biomaterials with therapeutic molecules play an active role in wound healing and infection prevention. In this work, the development of collagen hydrogels loaded with silver nanoparticles and Cannabis sativa oil extract is described. The presence of the silver nanoparticles gives interesting feature to the biomaterial such as improved mechanical properties or resistance to collagenase degradation but most important is the long-lasting antimicrobial effect. Cannabis sativa oil, which is known for its anti-inflammatory and analgesic effects, possesses antioxidant activity and successfully improved the biocompatibility and also enhances the antimicrobial activity of the nanocomposite. Altogether, these results suggest that this novel nanocomposite biomaterial is a promising alternative to common treatments of wound infections and wound healing.

17.
J Exp Biol ; 224(19)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34515309

RESUMO

Visual learning is vital to the behavioral ecology of the Western honey bee (Apis mellifera). Honey bee workers forage for floral resources, a behavior that requires the learning and long-term memory of visual landmarks, but how these memories are mapped to the brain remains poorly understood. To address this gap in our understanding, we collected bees that successfully learned visual associations in a conditioned aversion paradigm and compared gene expression correlates of memory formation in the mushroom bodies, a higher-order sensory integration center classically thought to contribute to learning, as well as the optic lobes, the primary visual neuropil responsible for sensory transduction of visual information. We quantified expression of CREB and CaMKII, two classical genetic markers of learning, and fen-1, a gene specifically associated with punishment learning in vertebrates. As expected, we found substantial involvement of the mushroom bodies for all three markers but additionally report the involvement of the optic lobes across a similar time course. Our findings imply the molecular involvement of a sensory neuropil during visual associative learning parallel to a higher-order brain region, furthering our understanding of how a tiny brain processes environmental signals.


Assuntos
Memória , Corpos Pedunculados , Animais , Abelhas/genética , Encéfalo , Aprendizagem , Neurópilo
18.
Ann Entomol Soc Am ; 114(5): 596-605, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34512858

RESUMO

Honey bees utilize their circadian rhythms to accurately predict the time of day. This ability allows foragers to remember the specific timing of food availability and its location for several days. Previous studies have provided strong evidence toward light/dark cycles being the primary Zeitgeber for honey bees. Work in our laboratory described large individual variation in the endogenous period length of honey bee foragers from the same colony and differences in the endogenous rhythms under different constant temperatures. In this study, we further this work by examining the temperature inside the honey bee colony. By placing temperature and light data loggers at different locations inside the colony we measured temperature at various locations within the colony. We observed significant oscillations of the temperature inside the hive, that show seasonal patterns. We then simulated the observed temperature oscillations in the laboratory and found that using the temperature cycle as a Zeitgeber, foragers present large individual differences in the phase of locomotor rhythms for temperature. Moreover, foragers successfully synchronize their locomotor rhythms to these simulated temperature cycles. Advancing the cycle by six hours, resulting in changes in the phase of activity in some foragers in the assay. The results are shown in this study highlight the importance of temperature as a potential Zeitgeber in the field. Future studies will examine the possible functional and evolutionary role of the observed phase differences of circadian rhythms.

19.
Biomed Pharmacother ; 141: 111947, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34328122

RESUMO

Cardiac fibroblasts (CF) play an important role in the healing process and in pathological remodeling of cardiac tissue. As sentinel cells in the heart, they respond to inflammatory stimuli, expressing cytokines and cell adhesion proteins, which ultimately lead to increased recruitment of monocytes and enhancement of the inflammatory response. Angiotensin II (Ang II) triggers an inflammatory response, leading to cardiac tissue remodeling. On the other hand, RvD1 has been shown to contribute to the resolution of inflammation; however, its role in Ang II-treated CF has not been addressed until now. The present research aimed to study the effect of RvD1 on cytokine levels, cell adhesion proteins expression in a model of Ang II-triggered inflammatory response. CF from adult Sprague Dawley rats were used to study mRNA and protein levels of MCP-1, IL-6, TNF-a, IL-10, ICAM-1 and VCAM-1; and adhesion of spleen mononuclear cells to CF after Ang II stimulation. Our results show that Ang II increased IL-6, MCP-1 and TNF-a mRNA levels, but only increased IL-6 and MCP-1 protein levels. These effects were blocked by Losartan, but not by PD123369. Moreover, RvD1 was able to prevent all Ang II effects in CF. Additionally, RvD1 reduced the intracellular Ca2+ increase triggered by Ang II, indicating that RvD1 acts in an early manner to block Ang II signaling. Conclusion: our findings confirm the pro-resolutive effects of inflammation by RvD1, which at the cardiovascular level, could contribute to repair damaged cardiac tissue.


Assuntos
Angiotensina II/toxicidade , Adesão Celular/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Ácidos Docosa-Hexaenoicos/farmacologia , Monócitos/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Adesão Celular/fisiologia , Células Cultivadas , Citocinas/biossíntese , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Expressão Gênica , Masculino , Monócitos/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley
20.
Front Cardiovasc Med ; 8: 660197, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34169098

RESUMO

Death of cardiac fibroblasts (CFs) by ischemia/reperfusion (I/R) has major implications for cardiac wound healing. In in vivo models of myocardial infarction, toll-like receptor 4 (TLR4) activation has been reported as a cardioprotector; however, it remains unknown whether TLR4 activation can prevent CF death triggered by simulated I/R (sI/R). In this study, we analyzed TLR4 activation in neonate CFs exposed to an in vitro model of sI/R and explored the participation of the pro-survival kinases Akt and ERK1/2. Simulated ischemia was performed in a free oxygen chamber in an ischemic medium, whereas reperfusion was carried out in normal culture conditions. Cell viability was analyzed by trypan blue exclusion and the MTT assay. Necrotic and apoptotic cell populations were evaluated by flow cytometry. Protein levels of phosphorylated forms of Akt and ERK1/2 were analyzed by Western blot. We showed that sI/R triggers CF death by necrosis and apoptosis. In CFs exposed only to simulated ischemia or only to sI/R, blockade of the TLR4 with TAK-242 further reduced cell viability and the activation of Akt and ERK1/2. Preconditioning with lipopolysaccharide (LPS) or treatment with LPS in ischemia or reperfusion was not protective. However, LPS incubation during both ischemia and reperfusion periods prevented CF viability loss induced by sI/R. Furthermore, LPS treatment reduced the sub-G1 population, but not necrosis of CFs exposed to sI/R. On the other hand, the protective effects exhibited by LPS were abolished when TLR4 was blocked and Akt and ERK1/2 were inhibited. In conclusion, our results suggest that TLR4 activation protects CFs from apoptosis induced by sI/R through the activation of Akt and ERK1/2 signaling pathways.

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