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1.
Hum Mol Genet ; 32(8): 1380-1400, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36537577

RESUMO

A functional nerve growth factor NGF-Tropomyosin Receptor kinase A (TrkA) system is an essential requisite for the generation and maintenance of long-lasting thermal and mechanical hyperalgesia in adult mammals. Indeed, mutations in the gene encoding for TrkA are responsible for a rare condition, named Hereditary Sensory and Autonomic Neuropathy type IV (HSAN IV), characterized by the loss of response to noxious stimuli, anhidrosis and cognitive impairment. However, to date, there is no available mouse model to properly understand how the NGF-TrkA system can lead to pathological phenotypes that are distinctive of HSAN IV. Here, we report the generation of a knock-in mouse line carrying the HSAN IV TrkAR649W mutation. First, by in vitro biochemical and biophysical analyses, we show that the pathological R649W mutation leads to kinase-inactive TrkA also affecting its membrane dynamics and trafficking. In agreement with the HSAN IV human phenotype, TrkAR649W/m mice display a lower response to thermal and chemical noxious stimuli, correlating with reduced skin innervation, in addition to decreased sweating in comparison to TrkAh/m controls. Moreover, the R649W mutation decreases anxiety-like behavior and compromises cognitive abilities, by impairing spatial-working and social memory. Our results further uncover unexplored roles of TrkA in thermoregulation and sociability. In addition to accurately recapitulating the clinical manifestations of HSAN IV patients, our findings contribute to clarifying the involvement of the NGF-TrkA system in pain sensation.


Assuntos
Modelos Animais de Doenças , Neuropatias Hereditárias Sensoriais e Autônomas , Receptor trkA , Humanos , Animais , Camundongos , Mutação , Receptor trkA/genética , Técnicas de Introdução de Genes , Fator de Crescimento Neural/metabolismo , Fosforilação , Genes Letais , Dor/metabolismo , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Pele/metabolismo , Pele/patologia , Sistema Nervoso Simpático/metabolismo , Hipo-Hidrose/metabolismo , Comportamento Animal
2.
J Chem Eng Data ; 69(10): 3629-3644, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39411181

RESUMO

The competitive adsorption of phenolic acids, secoiridoids, and flavonoids in a molecularly imprinted polymer (MIP) functionalized with 4-vinylpiridine (4VP) moieties is analyzed here considering vanillic acid, oleuropein, and quercetin as reference molecules. Measured adsorption isotherms highlight a much stronger binding capacity of the quercetin-MIP particles toward quercetin as compared with vanillic acid and oleuropein. The acquired data were used to design and scale-up sorption/desorption processes aiming at the fractionation of olive leaf extracts. We show that a simple adsorption process, avoiding many pre-preparation steps, is possible when working at a high extract concentration due to the strong binding capacity of the MIP for flavonoids, even when using aqueous mixtures with a large alcoholic content. Solvent-gradient/temperature-swing desorption led to a sequence of fractions with enrichment of non-flavonoids at low alcoholic content while glycosylated flavonoids were enriched in fractions with 40% < alcohol content < 80%. Enrichment factors of 13 and 12 were measured for luteolin-7-O-glucoside and apigenin-7-O-glucoside, respectively. Flavonoid aglycones were enriched in fractions with alcohol content >80% (enrichment factors >20 for luteolin and quercetin). The findings reported here demonstrate the usefulness of the developed materials and sorption/desorption conditions for agricultural residue valorization and circular bioeconomy.

3.
Sensors (Basel) ; 24(18)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39338777

RESUMO

The effects of occlusal splints on sport performance have already been studied, although their biomechanical impacts are often overlooked. We investigated the kinematical changes during running until exhaustion at severe intensity while wearing a mandibular advancement occlusal splint. Twelve trained runners completed (i) an incremental protocol on a track to determine their velocity corresponding to maximal oxygen uptake and (ii) two trials of square wave transition exercises at their velocity corresponding to maximal oxygen until exhaustion, wearing two occlusal splints (without and with mandibular advancement). Running kinematics were compared within laps performed during the square wave transition exercises and between splint conditions. The mandibular advancement occlusal splint increased the running distance covered (~1663 ± 402 vs. 1540 ± 397 m, p = 0.03), along with a noticeable lap effect in decreasing stride frequency (p = 0.04) and increasing stride length (p = 0.03) and duty factor (p < 0.001). No spatiotemporal differences were observed between splints, except for improved balance foot contact times in the mandibular advancement condition. An increased knee flexion angle at initial contact (p = 0.017) was noted along laps in the non-advancement condition, despite the fact that no differences between splints were found. Running patterns mainly shifted within laps rather than between conditions, indicating that a mandibular advancement occlusal splint had a trivial kinematical effect.


Assuntos
Placas Oclusais , Corrida , Humanos , Masculino , Adulto , Corrida/fisiologia , Fenômenos Biomecânicos/fisiologia , Avanço Mandibular/instrumentação , Avanço Mandibular/métodos , Feminino , Adulto Jovem , Consumo de Oxigênio/fisiologia
4.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396763

RESUMO

Epidemiological evidence emphasizes that excess fat mass is associated with an increased risk of severe COVID-19 disease. Nevertheless, the intricate interplay between SARS-CoV-2 and adipocytes remains poorly understood. It is crucial to decipher the progression of COVID-19 both in the acute phase and on long-term outcomes. In this study, an in vitro model using the human SGBS cell line (Simpson-Golabi-Behmel syndrome) was developed to investigate the infectivity of SARS-CoV-2 in adipocytes, and the effects of virus exposure on adipocyte function. Our results show that SGBS adipocytes expressing ACE2 are susceptible to SARS-CoV-2 infection, as evidenced by the release of the viral genome into the medium, detection of the nucleocapsid in cell lysates, and positive immunostaining for the spike protein. Infected adipocytes show remarkable changes compared to uninfected controls: increased surface area of lipid droplets, upregulated expression of genes of inflammation (Haptoglobin, MCP-1, IL-6, PAI-1), increased oxidative stress (MnSOD), and a concomitant reduction of transcripts related to adipocyte function (leptin, fatty acid synthase, perilipin). Moreover, exogenous expression of spike protein in SGBS adipocytes also led to an increase in lipid droplet size. In conclusion using the human SGBS cell line, we detected SARS-CoV-2 infectivity in adipocytes, revealing substantial morphological and functional changes in infected cells.


Assuntos
Arritmias Cardíacas , COVID-19 , Doenças Genéticas Ligadas ao Cromossomo X , Gigantismo , Cardiopatias Congênitas , Deficiência Intelectual , Glicoproteína da Espícula de Coronavírus , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Cultivadas , COVID-19/metabolismo , SARS-CoV-2 , Adipócitos/metabolismo , Fenótipo , Expressão Gênica
5.
J Strength Cond Res ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39303201

RESUMO

ABSTRACT: Cardoso, F, Costa, MJ, Colaço, P, Vilas-Boas, JP, Pinho, JC, Pyne, DB, and Fernandes, RJ. Ventilatory and perceived ergogenic effects of mandibular forward repositioning during running at maximal oxygen uptake intensity. J Strength Cond Res XX(X): 000-000, 2024-Wearing an intraoral dental splint may enhance ventilatory function and exercise performance. Nineteen runners performed on a 400-m outdoor track: (a) an incremental protocol to assess the velocity at maximal oxygen uptake (vV̇ o2 max) and (b) 2 square wave bouts wearing 2 intraoral splints (with and without mandibular forward repositioning). The time until exhaustion at vV̇ o2 max (TLimv V̇ o2 max), ventilatory variables, oxygen uptake (V̇ o2 ) kinetics, energetic profiling, perceived exertion and kinematics, were all measured. Ventilatory data were assessed breath-by-breath and perceived exertion evaluated using the Borg 6-20-point scale at the end of TLimv V̇ o2 max bouts. Images were recorded by video cameras (120 Hz) and kinematic measures retrieved using Kinovea. A paired t test was computed for comparison of splints ( p ≤ 0.05). With (vs. without) mandibular forward repositioning, runners increased their TLimv V̇ o2 max by ∼6% ( p = 0.03), coupled with higher ventilation (151 ± 22 vs. 147 ± 23 L·min -1 , p = 0.04), end-tidal oxygen tension (114.3 ± 3.7 vs. 112.9 ± 3.9 mm Hg, p = 0.003), and lower inspiratory time (0.526 ± 0.083 vs. 0.540 ± 0.090 seconds, p = 0.02), despite similar V̇ o2 kinetics (e.g., 49.0 ± 8.7 vs. 47.7 ± 8.6 ml∙kg∙min -1 of fast component amplitude) being observed. The energy expenditure was ∼8% higher ( p = 0.03) with the mandible forward, coupled with lower perceived exertion scores ( p = 0.04). Mandibular forward repositioning was effective in acutely improving running performance at vV̇ o2 max with ergogenic effects on ventilatory and perceived variables.

6.
Small ; 19(30): e2205871, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37058009

RESUMO

Mechanical stimulation modulates neural development and neuronal activity. In a previous study, magnetic "nano-pulling" is proposed as a tool to generate active forces. By loading neural cells with magnetic nanoparticles (MNPs), a precise force vector is remotely generated through static magnetic fields. In the present study, human neural stem cells (NSCs) are subjected to a standard differentiation protocol, in the presence or absence of nano-pulling. Under mechanical stimulation, an increase in the length of the neural processes which showed an enrichment in microtubules, endoplasmic reticulum, and mitochondria is found. A stimulation lasting up to 82 days induces a strong remodeling at the level of synapse density and a re-organization of the neuronal network, halving the time required for the maturation of neural precursors into neurons. The MNP-loaded NSCs are then transplanted into mouse spinal cord organotypic slices, demonstrating that nano-pulling stimulates the elongation of the NSC processes and modulates their orientation even in an ex vivo model. Thus, it is shown that active mechanical stimuli can guide the outgrowth of NSCs transplanted into the spinal cord tissue. The findings suggest that mechanical forces play an important role in neuronal maturation which could be applied in regenerative medicine.


Assuntos
Células-Tronco Neurais , Traumatismos da Medula Espinal , Camundongos , Animais , Humanos , Neurônios , Medula Espinal/fisiologia , Diferenciação Celular/fisiologia , Neurogênese , Células Cultivadas
7.
FASEB J ; 36(11): e22498, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-37036720

RESUMO

The binding of nerve growth factor (NGF) to the tropomyosin-related kinase A (TrkA) and p75NTR receptors activates a large variety of pathways regulating critical processes as diverse as proliferation, differentiation, membrane potential, synaptic plasticity, and pain. To ascertain the details of TrkA-p75NTR interaction and cooperation, a plethora of experiments, mostly based on receptor overexpression or downregulation, have been performed. Among the heterogeneous cellular systems used for studying NGF signaling, the PC12 pheochromocytoma-derived cell line is a widely used model. By means of CRISPR/Cas9 genome editing, we created PC12 cells lacking TrkA, p75NTR , or both. We found that TrkA-null cells become unresponsive to NGF. Conversely, the absence of p75NTR enhances the phosphorylation of TrkA and its effectors. Using a patch-clamp, we demonstrated that the individual activation of TrkA and p75NTR by NGF results in antagonizing effects on the membrane potential. These newly developed PC12 cell lines can be used to investigate the specific roles of TrkA and p75NTR in a genetically defined cellular model, thus providing a useful platform for future studies and further gene editing.


Assuntos
Receptor trkA , Receptores de Fator de Crescimento Neural , Animais , Ratos , Sistemas CRISPR-Cas , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Receptor trkA/genética , Receptor trkA/metabolismo , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/metabolismo
8.
Sensors (Basel) ; 23(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299840

RESUMO

The present study aimed to analyze swimmers' in-water kinetic and kinematic behaviors according to different swimming performance tiers within the same age group. An amount of 53 highly trained swimmers (girls and boys: 12.40 ± 0.74 years) were split up into 3 tiers based on their personal best performance (i.e., speed) in the 50 m freestyle event (short-course): lower-tier (1.25 ± 0.08 m·s-1); mid-tier (1.45 ± 0.04 m·s-1); and top-tier (1.60 ± 0.04 m·s-1). The in-water mean peak force was measured during a maximum bout of 25 m front crawl using a differential pressure sensors system (Aquanex system, Swimming Technology Research, Richmond, VA, USA) and defined as a kinetic variable, while speed, stroke rate, stroke length, and stroke index were retrieved and considered as kinematic measures. The top-tier swimmers were taller with a longer arm span and hand surface areas than the low-tier, but similar to the mid-tier. While the mean peak force, speed and efficiency differed among tiers, the stroke rate and stroke length showed mixed findings. Coaches should be aware that young swimmers belonging to the same age group may deliver different performance outcomes due to different kinetic and kinematic behaviors.


Assuntos
Natação , Água , Masculino , Feminino , Humanos , Fenômenos Biomecânicos , Cinética
9.
Sensors (Basel) ; 23(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37688089

RESUMO

Enhancing recovery is a fundamental component of high-performance sports training since it enables practitioners to potentiate physical performance and minimise the risk of injuries. Using a new sports legging embedded with an intelligent system for electrostimulation, localised heating and compression (completely embodied into the textile structures), we aimed to analyse acute recovery following a fatigue protocol. Surface electromyography- and torque-related variables were recorded on eight recreational athletes. A fatigue protocol conducted in an isokinetic dynamometer allowed us to examine isometric torque and consequent post-exercise acute recovery after using the sports legging. Regarding peak torque, no differences were found between post-fatigue and post-recovery assessments in any variable; however, pre-fatigue registered a 16% greater peak torque when compared with post-fatigue for localised heating and compression recovery methods. Our data are supported by recent meta-analyses indicating that individual recovery methods, such as localised heating, electrostimulation and compression, are not effective to recover from a fatiguing exercise. In fact, none of the recovery methods available through the sports legging tested was effective in acutely recovering the torque values produced isometrically.


Assuntos
Atletas , Desempenho Atlético , Humanos , Exercício Físico , Terapia por Exercício , Fadiga
10.
Int J Mol Sci ; 24(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298419

RESUMO

The normal growth and operation of the central nervous system (CNS) at all stages of development, including adulthood, depend on the interaction between intrinsic and extrinsic factors [...].


Assuntos
Neoplasias Encefálicas , Transtornos do Neurodesenvolvimento , Humanos , Adulto , Sistema Nervoso Central , Transtornos do Neurodesenvolvimento/genética , Neoplasias Encefálicas/genética , Neurônios , Encéfalo
11.
J Sports Sci Med ; 22(3): 417-424, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37711703

RESUMO

The aim of the present study was two-fold: (i) to analyze the progression and variability of swimming performance (from entry times to best performances) in the 50, 100, and 200 m at the most recent FINA World Championships and (ii) to compare the performance of the Top16, semifinalists, and finalists between all rounds. Swimmers who qualified with the FINA A and B standards for the Budapest 2022 World Championships were considered. A total of 1102 individual performances swimmers were analyzed in freestyle, backstroke, breaststroke, and butterfly events. The data was retrieved from the official open-access websites of OMEGA and FINA. Wilcoxon test was used to compare swimmers' entry times and best performances. Repeated measures ANOVA followed by the Bonferroni post-hoc test were performed to analyze the round-to-round progression. The percentage of improvement and variation in the swimmers' performance was computed between rounds. A negative progression (entry times better than best performance) and a high variability (> 0.69%) were found for most events. The finalists showed a positive progression with a greater improvement (~1%) from the heats to the semifinals. However, the performance progression remained unchanged between the semifinals and finals. The variability tended to decrease between rounds making each round more homogeneous. Coaches and swimmers can use these indicators to prepare a race strategy between rounds.


Assuntos
Temperatura Alta , Natação , Humanos
12.
Scand J Med Sci Sports ; 32(3): 465-486, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34913530

RESUMO

Aquatic exercise is being increasingly recommended for healthy individuals as well as people with some special health conditions. A systematic review with meta-analysis was performed to synthesize and analyze data on the effects of water-based training (WT) programs on health status and physical fitness of healthy adults and adults with diseases to develop useful recommendations for health and sports professionals. We searched three databases (PubMed, Web of Science, and Scopus) up to June 2021 for randomized trials that examined WT in adults. A total of 62 studies were included, of which 26 involved only healthy individuals and 36 focused on adults with chronic diseases. In the healthy group, the effects of WT on strength, balance, and cardiorespiratory fitness were beneficial, indicating the usefulness of performing WT for at least 12 weeks (2-3x/week, 46-65 min/session). Among adults with diseases, improvements were observed in patients with fibromyalgia (in balance and cardiorespiratory fitness), bone diseases (pain, balance, flexibility, and strength), coronary artery disease (strength and anthropometry), hypertension (quality of life), stroke (quality of life), diabetes (balance and quality of life), multiple sclerosis (quality of life and balance), and Parkinson's disease (pain, gait, cardiorespiratory fitness, and quality of life). Research is required to determine the effects of WT on patients with heart disease, especially coronary artery disease. In adults with chronic disease, benefits in physical fitness and/or other health-related measures were mainly observed after 8-16 weeks of training. WT is an effective physical activity when the intention is to enhance health and physical fitness in healthy adults and adults with chronic diseases.


Assuntos
Aptidão Cardiorrespiratória , Qualidade de Vida , Adulto , Doença Crônica , Exercício Físico , Terapia por Exercício , Humanos , Aptidão Física
13.
Int J Mol Sci ; 23(16)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36012156

RESUMO

Among Histone post-translational modifications (PTMs), lysine acetylation plays a pivotal role in the epigenetic regulation of gene expression, mediated by chromatin modifying enzymes. Due to their activity in physiology and pathology, several chemical compounds have been developed to inhibit the function of these proteins. However, the pleiotropy of these classes of proteins represents a weakness of epigenetic drugs. Ideally, a new generation of epigenetic drugs should target with molecular precision individual acetylated lysines on the target protein. We exploit a PTM-directed interference, based on an intrabody (scFv-58F) that selectively binds acetylated lysine 9 of histone H3 (H3K9ac), to test the hypothesis that targeting H3K9ac yields more specific effects than inhibiting the corresponding HAT enzyme that installs that PTM. In yeast scFv-58F modulates, gene expression in a more specific way, compared to two well-established HAT inhibitors. This PTM-specific interference modulated expression of genes involved in ribosome biogenesis and function. In mammalian cells, the scFv-58F induces exclusive changes in the H3K9ac-dependent expression of specific genes. These results suggest the H3K9ac-specific intrabody as the founder of a new class of molecules to directly target histone PTMs, inverting the paradigm from inhibiting the writer enzyme to acting on the PTM.


Assuntos
Histonas , Lisina , Acetilação , Animais , Epigênese Genética , Expressão Gênica , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Mamíferos/metabolismo , Processamento de Proteína Pós-Traducional
14.
Molecules ; 27(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36234945

RESUMO

Residual diatomaceous earth (RDE) from winemaking activities is a rich and currently underexploited source of phenolic compounds which ought to be recycled from the perspective of circular bioeconomy. In this work, we demonstrate the feasibility of molecularly imprinted polymers (MIPs) for the enrichment of quercetin, a flavonoid at a fairly high content in residual diatomaceous earth. These MIPs were synthesized through free radical polymerization. FTIR confirmed the integration of the functional monomers into the polymeric chains. Batch adsorption experiments were used to assess the retention and selectivity of those MIPs towards quercetin. Commercial resins were compared with the synthesized materials using the same procedures. These adsorption experiments allowed the selection of the best performing MIP for the valorization of RDE extract. This treatment consisted of saturating the selected MIP with the extract and then desorbing the retained compounds using solvents of selected compositions. The desorbed fractions were analyzed using liquid chromatography, and the results demonstrated an increase in quercetin's fractional area from 5% in the RDE extract to more than 40% in some fractions, which is roughly an eightfold enrichment of quercetin. Moreover, other flavonoids of close chemical structure to quercetin have been rather retained and enriched by the MIP.


Assuntos
Impressão Molecular , Quercetina , Adsorção , Terra de Diatomáceas , Flavonoides , Polímeros Molecularmente Impressos , Extratos Vegetais/química , Quercetina/química , Extração em Fase Sólida/métodos , Solventes
15.
J Neurosci ; 40(26): 4997-5007, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32444384

RESUMO

Stretch-growth has been defined as a process that extends axons via the application of mechanical forces. In the present article, we used a protocol based on magnetic nanoparticles (NPs) for labeling the entire axon tract of hippocampal neurons, and an external magnetic field gradient to generate a dragging force. We found that the application of forces below 10 pN induces growth at a rate of 0.66 ± 0.02 µm h-1 pN-1 Calcium imaging confirmed the strong increase in elongation rate, in comparison with the condition of tip-growth. Enhanced growth in stretched axons was also accompanied by endoplasmic reticulum (ER) accumulation and, accordingly, it was blocked by an inhibition of translation. Stretch-growth was also found to stimulate axonal branching, glutamatergic synaptic transmission, and neuronal excitability. Moreover, stretched axons showed increased microtubule (MT) density and MT assembly was key to sustaining stretch-growth, suggesting a possible role of tensile forces in MT translocation/assembly. Additionally, our data showed that stretched axons do not respond to BDNF signaling, suggesting interference between the two pathways. As these extremely low mechanical forces are physiologically relevant, stretch-growth could be an important endogenous mechanism of axon growth, with a potential for designing novel strategies for axonal regrowth.SIGNIFICANCE STATEMENT Axon growth involves motion, and motion is driven by forces. The growth cone (GC) itself can generate very low intracellular forces by inducing a drastic cytoskeleton remodeling, in response to signaling molecules. Here, we investigated the key role of intracellular force as an endogenous regulator of axon outgrowth, which it has been neglected for decades because of the lack of methodologies to investigate the topic. Our results indicate a critical role of force in promoting axon growth by facilitating microtubule (MT) polymerization.


Assuntos
Cones de Crescimento/fisiologia , Mecanotransdução Celular/fisiologia , Crescimento Neuronal/fisiologia , Animais , Hipocampo/crescimento & desenvolvimento , Magnetismo , Nanopartículas Metálicas , Camundongos , Camundongos Endogâmicos C57BL
16.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806766

RESUMO

Cutaneous melanoma is often resistant to therapy due to its high plasticity, as well as its ability to metabolise chemotherapeutic drugs. Sphingolipid signalling plays a pivotal role in its progression and metastasis. One of the ways melanoma alters sphingolipid rheostat is via over-expression of lysosomal acid ceramidase (AC), which catalyses the hydrolysis of pro-apoptotic long-chain ceramides into sphingosine and fatty acid. In this report, we examine the role of acid ceramidase in maintaining cellular homeostasis through the regulation of autophagy and mitochondrial activity in melanoma cell lines. We show that under baseline conditions, wild-type melanoma cells had 3-fold higher levels of the autophagy marker, microtubule-associated proteins 1A/1B light chain 3B (LC3 II), compared to AC-null cells. This difference was further magnified after cell starvation. Moreover, we noticed autophagy impairment in A375 AC-null cells, possibly due to local accumulation of non-metabolized ceramides. Nonetheless, we observed that AC-null cells exhibited a significant increase in mitochondrial membrane potential compared to control cells. Consistent with this observation, we found that, after total starvation, ~30% of AC-null cells undergo apoptosis compared to ~6% of wild-type cells. As expected, AC transfection restored viability in A375 AC-null cells. Together, these findings suggest that AC-null melanoma cells change and adapt their metabolism to survive in the absence of AC, although in a way that does not allow them to cope with the stress of nutrient deprivation.


Assuntos
Ceramidase Ácida/genética , Autofagia/genética , Melanoma/genética , Melanoma/metabolismo , Mitocôndrias/genética , Ceramidase Ácida/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Imunofluorescência , Expressão Gênica , Humanos , Melanoma/patologia , Potencial da Membrana Mitocondrial , Fator de Transcrição Associado à Microftalmia/genética , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética
17.
J Sports Sci Med ; 20(4): 714-720, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35321138

RESUMO

The aim of this study was to analyze the progression and stability in the performance of world-ranked swimmers from 2015 to 2020, and the impairment induced by the COVID-19 lockdown. An observational retrospective design over five consecutive competitive seasons was selected. FINA's male Top-50 who were qualified for the Tokyo Olympic Games were considered in freestyle, backstroke, backstroke, and butterfly events. A total of 515 male swimmers and 2060 season-best performances were analyzed. All data was retrieved from two open-access and public websites (Swimrankings and Swimcloud). Repeated measures ANOVA followed by the Bonferroni post-hoc test was performed to analyze the variation between seasons. Stabilization in performance was assessed using spearman correlation coefficients. A significant improvement in performance ≈0.5-2.5% was found in most of the strokes and race distances until the 2018-2019 season. The 2020 lockdown impaired the performance by 1-2%. Moderate to high associations were found in the 2017-2018 season when considering the 2019-2020 performance. The breaststroke was the only stroke with a moderate-high stability (r > 0.40) in all race distances considering the overall time period. It can be concluded that world-ranked swimmers' performance was impaired by 1-2% due to the COVID-19 lockdown, returning to levels that were reached two years earlier.


Assuntos
COVID-19 , Natação , Controle de Doenças Transmissíveis , Humanos , Masculino , Estudos Retrospectivos , Tóquio/epidemiologia
18.
J Neurosci ; 39(49): 9702-9715, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685654

RESUMO

Nerve growth factor (NGF) is a key mediator of nociception, acting during the development and differentiation of dorsal root ganglion (DRG) neurons, and on adult DRG neuron sensitization to painful stimuli. NGF also has central actions in the brain, where it regulates the phenotypic maintenance of cholinergic neurons. The physiological function of NGF as a pain mediator is altered in patients with Hereditary Sensory and Autonomic Neuropathy type V (HSAN V), caused by the 661C>T transition in the Ngf gene, resulting in the R100W missense mutation in mature NGF. Homozygous HSAN V patients present with congenital pain insensitivity, but are cognitively normal. This led us to hypothesize that the R100W mutation may differentially affect the central and peripheral actions of NGF. To test this hypothesis and provide a mechanistic basis to the HSAN V phenotype, we generated transgenic mice harboring the human 661C>T mutation in the Ngf gene and studied both males and females. We demonstrate that heterozygous NGFR100W/wt mice display impaired nociception. DRG neurons of NGFR100W/wt mice are morphologically normal, with no alteration in the different DRG subpopulations, whereas skin innervation is reduced. The NGFR100W protein has reduced capability to activate pain-specific signaling, paralleling its reduced ability to induce mechanical allodynia. Surprisingly, however, NGFR100W/wt mice, unlike heterozygous mNGF+/- mice, show no learning or memory deficits, despite a reduction in secretion and brain levels of NGF. The results exclude haploinsufficiency of NGF as a mechanistic cause for heterozygous HSAN V mice and demonstrate a specific effect of the R100W mutation on nociception.SIGNIFICANCE STATEMENT The R100W mutation in nerve growth factor (NGF) causes Hereditary Sensory and Autonomic Neuropathy type V, a rare disease characterized by impaired nociception, even in apparently clinically silent heterozygotes. For the first time, we generated and characterized heterozygous knock-in mice carrying the human R100W-mutated allele (NGFR100W/wt). Mutant mice have normal nociceptor populations, which, however, display decreased activation of pain transduction pathways. NGFR100W interferes with peripheral and central NGF bioavailability, but this does not impact on CNS function, as demonstrated by normal learning and memory, in contrast with heterozygous NGF knock-out mice. Thus, a point mutation allows neurotrophic and pronociceptive functions of NGF to be split, with interesting implications for the treatment of chronic pain.


Assuntos
Cognição , Neuropatias Hereditárias Sensoriais e Autônomas/genética , Neuropatias Hereditárias Sensoriais e Autônomas/fisiopatologia , Mutação/genética , Fator de Crescimento Neural/genética , Nociceptividade , Animais , Comportamento Animal , Feminino , Gânglios Espinais/patologia , Técnicas de Introdução de Genes , Neuropatias Hereditárias Sensoriais e Autônomas/psicologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mutação de Sentido Incorreto/genética , Medição da Dor , Percepção da Dor , Desempenho Psicomotor , Ratos , Ratos Wistar , Pele/inervação
19.
Neurobiol Dis ; 141: 104942, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32423877

RESUMO

Recent studies have demonstrated an active role for neurons in glioma progression. Specifically, peritumoral neurons establish functional excitatory synapses with glioma cells, and optogenetic stimulation of cortical pyramidal neurons drives tumor progression. However, the specific role of different subsets of cortical neurons, such as GABAergic interneurons, remains unexplored. Here, we directly compared the effects of optogenetic stimulation of pyramidal cells vs. fast-spiking, GABAergic neurons. In mice inoculated with GL261 cells into the motor cortex, we show that optogenetic stimulation of pyramidal neurons enhances glioma cell proliferation. In contrast, optogenetic stimulation of fast-spiking, parvalbumin-positive interneurons reduces proliferation as measured by BrdU incorporation and Ki67 immunolabelling. Since both principal cells and fast-spiking interneurons are directly activated by sensory afferent input, we next placed tumors in the occipital cortex to test the impact of visual stimulation/deprivation. We report that total lack of visual input via dark rearing enhances the density of proliferating glioma cells, while daily visual stimulation by gratings of different spatial frequencies and contrast reduces tumor growth. The effects of sensory input are region-specific, as visual deprivation has no significant effect on tumor proliferation in mice with gliomas in the motor cortex. We also report that sensory stimulation combined with temozolomide administration delays the loss of visual responses in peritumoral neurons. Altogether, these data demonstrate complex effects of different neuronal subtypes in the control of glioma proliferation.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Proliferação de Células , Neurônios GABAérgicos/fisiologia , Glioma/fisiopatologia , Células Piramidais/fisiologia , Animais , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Córtex Motor/fisiopatologia , Optogenética
20.
Int J Mol Sci ; 20(17)2019 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-31450553

RESUMO

The correct morphofunctional shaping of the cerebral cortex requires a continuous interaction between intrinsic (genes/molecules expressed within the tissue) and extrinsic (e.g., neural activity) factors at all developmental stages. Forkhead Box G1 (FOXG1) is an evolutionarily conserved transcription factor, essential for the cerebral cortex patterning and layering. FOXG1-related disorders, including the congenital form of Rett syndrome, can be caused by deletions, intragenic mutations or duplications. These genetic alterations are associated with a complex phenotypic spectrum, spanning from intellectual disability, microcephaly, to autistic features, and epilepsy. We investigated the functional correlates of dysregulated gene expression by performing electrophysiological assays on FoxG1+/- mice. Local Field Potential (LFP) recordings on freely moving animals detected cortical hyperexcitability. On the other hand, patch-clamp recordings showed a downregulation of spontaneous glutamatergic transmission. These findings were accompanied by overactivation of Akt/S6 signaling. Furthermore, the expression of vesicular glutamate transporter 2 (vGluT2) was increased, whereas the level of the potassium/chloride cotransporter KCC2 was reduced, thus indicating a higher excitation/inhibition ratio. Our findings provide evidence that altered expression of a key gene for cortical development can result in specific alterations in neural circuit function at the macro- and micro-scale, along with dysregulated intracellular signaling and expression of proteins controlling circuit excitability.


Assuntos
Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Epilepsia/genética , Epilepsia/metabolismo , Fatores de Transcrição Forkhead/genética , Proteínas do Tecido Nervoso/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Transmissão Sináptica , Animais , Modelos Animais de Doenças , Suscetibilidade a Doenças , Epilepsia/fisiopatologia , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Camundongos , Camundongos Knockout , Fenótipo , Convulsões , Transdução de Sinais , Potenciais Sinápticos
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