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1.
Mol Cell ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38981483

RESUMO

Metabolic enzymes can adapt during energy stress, but the consequences of these adaptations remain understudied. Here, we discovered that hexokinase 1 (HK1), a key glycolytic enzyme, forms rings around mitochondria during energy stress. These HK1-rings constrict mitochondria at contact sites with the endoplasmic reticulum (ER) and mitochondrial dynamics protein (MiD51). HK1-rings prevent mitochondrial fission by displacing the dynamin-related protein 1 (Drp1) from mitochondrial fission factor (Mff) and mitochondrial fission 1 protein (Fis1). The disassembly of HK1-rings during energy restoration correlated with mitochondrial fission. Mechanistically, we identified that the lack of ATP and glucose-6-phosphate (G6P) promotes the formation of HK1-rings. Mutations that affect the formation of HK1-rings showed that HK1-rings rewire cellular metabolism toward increased TCA cycle activity. Our findings highlight that HK1 is an energy stress sensor that regulates the shape, connectivity, and metabolic activity of mitochondria. Thus, the formation of HK1-rings may affect mitochondrial function in energy-stress-related pathologies.

2.
ACS Sens ; 9(3): 1261-1271, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38293866

RESUMO

When a cell sustains damage, it liberates cytosolic ATP, which can serve as an injury signal, affecting neighboring cells. This study presents a methodological approach that employs in vitro axotomy and in vivo laser ablation to simulate cellular injury. Specially tailored biosensors are employed to monitor ATP dynamics and calcium transients in injured cells and their surroundings. To simultaneously visualize extracellular and cytosolic ATP, we developed bicistronic constructs featuring GRABATP1.0 and MaLionR biosensors alongside the calcium sensor RCaMP, enabling multiparametric imaging. In addition to transducing primary neuron cultures, we developed another method where we cocultured dorsal root ganglion neurons together with specialized "sniffer" cell lines expressing the bicistronic biosensors. Exploiting these approaches, we successfully demonstrated the release of ATP from the injured neurons and its extracellular diffusion in response to cellular injury in vitro and in vivo. Axotomy triggered intracellular calcium mobilization not only in the injured neuron but also in the intact neighboring cells, providing new insights into ATP's role as an injury signal. The tools developed in this study have demonstrated remarkable efficiency in unraveling the intricacies of ATP-mediated injury signaling.


Assuntos
Técnicas Biossensoriais , Cálcio , Ratos , Animais , Cálcio/metabolismo , Ratos Sprague-Dawley , Neurônios/metabolismo , Trifosfato de Adenosina
3.
iScience ; 26(10): 107715, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37701578

RESUMO

Trauma, vascular events, or neurodegenerative processes can lead to axonal injury and eventual transection (axotomy). Neurons can survive axotomy, yet the underlying mechanisms are not fully understood. Excessive water entry into injured neurons poses a particular risk due to swelling and subsequent death. Using in vitro and in vivo neurotrauma model systems based on laser transection and surgical nerve cut, we demonstrated that axotomy triggers actomyosin contraction coupled with calpain activity. As a consequence, neurons shrink acutely to force water out through aquaporin channels preventing swelling and bursting. Inhibiting shrinkage increased the probability of neuronal cell death by about 3-fold. These studies reveal a previously unrecognized cytoprotective response mechanism to neurotrauma and offer a fresh perspective on pathophysiological processes in the nervous system.

4.
East Mediterr Health J ; 29(5): 343-353, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37306171

RESUMO

Background: Although vaccines play a critical role in the control of infectious diseases and disease outbreaks, vaccination rates have been declining in recent years because of vaccine hesitancy or refusal. Aims: We aimed to determine the rates and reasons for parental hesitancy or refusal of vaccination for their children in Türkiye. Method: A total of 1100 participants selected from 26 regions of Türkiye were involved in this cross-sectional study conducted between July 2020 and April 2021. Using a questionnaire, we collected data on the sociodemographic characteristics of parents, the status of vaccine hesitancy or refusal for their children, and reasons for the hesitancy or refusal. Using Excel and SPSS version 22.0, we analysed the data with chi-square test, Fisher's exact test and binomial logistic regression. Results: Only 9.4% of the participants were male and 29.5% were aged 33-37 years. Just over 11% said they were worried about childhood vaccination, mainly because of the chemicals used in manufacturing the vaccines. The level of concern was greater among those who got information about vaccines from the internet, family members, friends, TV, radio, and newspapers. Those who used complementary health services were considerably more hesitant about vaccination than those who used mainstream services. Conclusions: Parents in Türkiye have several reasons for hesitating or refusing to vaccinate their children, key among which are concerns about the chemical composition of the vaccines and their ability to trigger negative health conditions such as autism. This study used a large sample size across Türkiye, although there were differences by region, the findings would be useful in designing interventions to counter vaccine hesitancy or refusal in the country.


Assuntos
Transtorno Autístico , Pais , Criança , Humanos , Masculino , Feminino , Estudos Transversais , Família , Vacinação
5.
J Am Chem Soc ; 145(22): 11899-11902, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37222194

RESUMO

Chemogenetic Operation of iNTRacellular prOton Levels (pH-Control) is a novel substrate-based enzymatic method that enables precise spatiotemporal control of ultralocal acidification in cultured cell lines and primary neurons. The genetically encoded biosensor SypHer3s showed that pH-Control effectively acidifies cytosolic, mitochondrial, and nuclear pH exclusively in the presence of ß-chloro-d-alanine in living cells in a concentration-dependent manner. The pH-Control approach is promising for investigating the ultralocal pH imbalance associated with many diseases.


Assuntos
Prótons , Concentração de Íons de Hidrogênio , Linhagem Celular , Homeostase , Citosol/metabolismo
6.
Mol Omics ; 19(3): 218-228, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36723117

RESUMO

The most common treatment strategies for Parkinson's disease (PD) aim to slow down the neurodegeneration process or control the symptoms. In this study, using an in vitro PD model we carried out a transcriptome-based drug target prediction strategy. We identified novel drug target candidates by mapping genes upregulated in 6-OHDA-treated cells on a human protein-protein interaction network. Among the predicted targets, we show that AKR1C3 and CEBPB are promising in validating our bioinformatics approach since their known ligands, rutin and quercetin, respectively, act as neuroprotective drugs that effectively decrease cell death, and restore the expression profiles of key genes upregulated in 6-OHDA-treated cells. We also show that these two genes upregulated in our in vitro PD model are downregulated to basal levels upon drug administration. As a further validation of our methodology, we further confirm that the potential target genes identified with our bioinformatics approach are also upregulated in post-mortem transcriptome samples of PD patients from the literature. Therefore, we propose that this methodology predicts novel drug targets AKR1C3 and CEBPB, which are relevant to future clinical applications as potential drug repurposing targets for PD. Our systems-based computational approach to predict candidate drug targets can be employed in identifying novel drug targets in other diseases without a priori assumption.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Transcriptoma/genética , Oxidopamina/farmacologia , Oxidopamina/uso terapêutico , Preparações Farmacêuticas , Mapas de Interação de Proteínas/genética
7.
Turk J Med Sci ; 53(5): 1358-1366, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38813001

RESUMO

Background/aim: Dorsal root ganglia (DRG) are structures containing primary sensory neurons. Intraganglionic (IG) and intrathecal (IT) applications are the most common methods used for viral vector transfer to DRG. We aim to compare the efficiencies and pathological effects of IT and IG viral vector delivery methods to DRG, through in vivo imaging. Materials and methods: Mice were divided into four groups of six each: IT, IG, IT-vehicle, and IG-vehicle. Adeno-associated virus (AAV) injection was performed for EGFP expression in IT/IG groups. DRGs were made visible through vertebral window surgery and visualized with multiphoton microscopy. After imaging, spinal cords and DRGs were removed and cleared, then imaged with light sheet microscopy. Results: No neuronal death was observed after IT injection, while the death rate was 17% 24 h after IG injection. EGFP expression efficiencies were 90%-95% of neurons in both groups. EGFP expression was only observed in targeted L2 DRG after IG injection, while it was observed in DRGs located between L1-L5 levels after IT injection. Conclusion: IT injection is a more suitable method for labeling DRG neurons in neurodegenerative injury models. However, when the innervation of DRG needs to be specifically studied, IT injection reduces this specificity due to its spread. In these studies, IG injection is the most suitable method for labeling single DRG neurons.


Assuntos
Gânglios Espinais , Injeções Espinhais , Animais , Gânglios Espinais/metabolismo , Injeções Espinhais/métodos , Camundongos , Dependovirus/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genética , Vetores Genéticos/administração & dosagem , Masculino
9.
Redox Biol ; 53: 102319, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525027

RESUMO

Iron is an essential metal for cellular metabolism and signaling, but it has adverse effects in excess. The physiological consequences of iron deficiency are well established, yet the relationship between iron supplementation and pericellular oxygen levels in cultured cells and their downstream effects on metalloproteins has been less explored. This study exploits the metalloprotein geNOps in cultured HEK293T epithelial and EA.hy926 endothelial cells to test the iron-dependency in cells adapted to standard room air (18 kPa O2) or physiological normoxia (5 kPa O2). We show that cells in culture require iron supplementation to activate the metalloprotein geNOps and demonstrate for the first time that cells adapted to physiological normoxia require significantly lower iron compared to cells adapted to hyperoxia. This study establishes an essential role for recapitulating oxygen levels in vivo and uncovers a previously unrecognized requirement for ferrous iron supplementation under standard cell culture conditions to achieve geNOps functionality.


Assuntos
Técnicas Biossensoriais , Metaloproteínas , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Ferro/metabolismo , Metaloproteínas/metabolismo , Óxido Nítrico/metabolismo , Oxigênio/metabolismo
10.
Hum Vaccin Immunother ; 17(12): 5191-5195, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34905472

RESUMO

INTRODUCTION: Although there is a lot of scientific evidence that the benefits of vaccines outweigh their risks, hesitancy about the safety of vaccines can occur in every segment of the community. In this study, we aimed to determine the knowledge, attitudes, and associated factors of vaccine hesitancy among Inonu University faculty members regarding childhood vaccinations. METHOD: This is a cross-sectional study, and 258 faculty members were included in the study. The questionnaire used in the study explored the sociodemographic characteristics of the faculty members and their knowledge, attitudes and behaviors regarding childhood vaccination. A chi-square test and a fisher exact test were used for statistical analysis. RESULTS: Of the faculty members, 31.8% were hesitant about childhood vaccines, 51.9% stated that there were studies reporting the side effects of vaccines, 48.1% did not agree with giving booster doses of vaccines, 35.7% stated that vaccines could cause autism due to the chemicals contained in the vaccines. The most important information sources of university faculty regarding childhood vaccines members are scientific publications and health professionals. CONCLUSIONS: Faculty members level of hesitancy about vaccines was high and since health professionals and scientific articles are the most important information sources of faculty members, misinformation here may affect their knowledge, attitudes and behaviors about vaccination.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Vacinas , Estudos Transversais , Docentes , Humanos , Pais , Aceitação pelo Paciente de Cuidados de Saúde , Universidades , Vacinação , Recusa de Vacinação , Vacinas/efeitos adversos
11.
Biosensors (Basel) ; 11(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34562927

RESUMO

Multispectral live-cell imaging is an informative approach that permits detecting biological processes simultaneously in the spatial and temporal domain by exploiting spectrally distinct biosensors. However, the combination of fluorescent biosensors with distinct spectral properties such as different sensitivities, and dynamic ranges can undermine accurate co-imaging of the same analyte in different subcellular locales. We advanced a single-color multiparametric imaging method, which allows simultaneous detection of hydrogen peroxide (H2O2) in multiple cell locales (nucleus, cytosol, mitochondria) using the H2O2 biosensor HyPer7. Co-culturing of endothelial cells stably expressing differentially targeted HyPer7 biosensors paved the way for co-imaging compartmentalized H2O2 signals simultaneously in neighboring cells in a single experimental setup. We termed this approach COMPARE IT, which is an acronym for co-culture-based multiparametric imaging technique. Employing this approach, we detected lower H2O2 levels in mitochondria of endothelial cells compared to the cell nucleus and cytosol under basal conditions. Upon administering exogenous H2O2, the cytosolic and nuclear-targeted probes displayed similarly slow and moderate HyPer7 responses, whereas the mitochondria-targeted HyPer7 signal plateaued faster and reached higher amplitudes. Our results indicate striking differences in mitochondrial H2O2 accumulation of endothelial cells. Here, we present the method's potential as a practicable and informative multiparametric live-cell imaging technique.


Assuntos
Técnicas Biossensoriais , Técnicas de Cocultura , Células Endoteliais/metabolismo , Peróxido de Hidrogênio/metabolismo , Mitocôndrias
12.
Hum Vaccin Immunother ; 17(11): 4512-4517, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473585

RESUMO

Among 10 global problems of 2019 determined by the World Health Organization, vaccine refusal was one of the problems mentioned. In this context, health services and health personnel whose main objectives are to keep individuals healthy and to prevent diseases have major responsibilities. This study aims to analyze knowledge and behavior of nurses working at Inonu University Turgut Ozal Medical Center on childhood vaccine refusal.This study, conducted between June and July 2019, is a descriptive cross-sectional study. It was conducted in a hospital located in Malatya in eastern Turkey. At the time of the study, 850 nurses work in this hospital. Sample size was calculated to be 263 at a confidence interval of 95% and strength of 80%. Chi-square test and Fisher's exact test were used in statistical analyses.In the present study, 31.7% of the participating nurses stated that they had concerns about childhood vaccines. Two-thirds of nurses stated that their knowledge on vaccines was from their education. The level of hesitance in those agreeing to the fact that vaccines caused autism and infertility, those stating that they did not trust vaccine-producing companies, and those stating that catching the disease was a better immunization method than vaccination was significantly higher than those not agreeing to these and those who were indecisive (p < .05).One-third of nurses was proven to have hesitance on childhood vaccines, and this rate is rather high. Nurses, being both health personnel and the communication channel for guiding parents, should be provided necessary training and practices in order to ease their hesitance on vaccination.


Assuntos
Universidades , Vacinas , Criança , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pais , Inquéritos e Questionários , Vacinação , Recusa de Vacinação
13.
PLoS One ; 16(3): e0246924, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33657119

RESUMO

Cultured sensory neurons can exhibit complex activity patterns following stimulation in terms of increased excitability and interconnected responses of multiple neurons. Although these complex activity patterns suggest a network-like configuration, research so far had little interest in synaptic network formation ability of the sensory neurons. To identify interaction profiles of Dorsal Root Ganglia (DRG) neurons and explore their putative connectivity, we developed an in vitro experimental approach. A double transgenic mouse model, expressing genetically encoded calcium indicator (GECI) in their glutamatergic neurons, was produced. Dissociated DRG cultures from adult mice were prepared with a serum-free protocol and no additional growth factors or cytokines were utilized for neuronal sensitization. DRG neurons were grown on microelectrode arrays (MEA) to induce stimulus-evoked activity with a modality-free stimulation strategy. With an almost single-cell level electrical stimulation, spontaneous and evoked activity of GCaMP6s expressing neurons were detected under confocal microscope. Typical responses were analyzed, and correlated calcium events were detected across individual DRG neurons. Next, correlated responses were successfully blocked by glutamatergic receptor antagonists, which indicated functional synaptic coupling. Immunostaining confirmed the presence of synapses mainly in the axonal terminals, axon-soma junctions and axon-axon intersection sites. Concisely, the results presented here illustrate a new type of neuron-to-neuron interaction in cultured DRG neurons conducted through synapses. The developed assay can be a valuable tool to analyze individual and collective responses of the cultured sensory neurons.


Assuntos
Técnicas de Cultura de Células/métodos , Gânglios Espinais/citologia , Sinaptofisina/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/genética , Animais , Comunicação Celular , Células Cultivadas , Estimulação Elétrica , Gânglios Espinais/metabolismo , Camundongos , Camundongos Transgênicos , Receptores de Glutamato/metabolismo
14.
Neurosci Lett ; 738: 135348, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32891673

RESUMO

Pea3 proteins belong to a subfamily of the E-twentysix (ETS) domain superfamily of transcription factors, which play various roles during development. Polyoma Enhancer-Activator 3 (Pea3) proteins Pea3, ERM and Er81 are particularly involved in tissues with branching morphogenesis, including kidney, lung, mammary gland and nervous system development. A recent transcriptomic study on novel targets of Pea3 transcription factor revealed various axon guidance and nervous system development related targets, supporting a role of Pea3 proteins in motor neuron connectivity, as well as novel targets in signaling pathways involved in synaptic plasticity. This study focuses on the expression of Pea3 family members in hippocampal neurons, and regulation of putative Pea3 targets in Pea3-overexpressing cell lines and following induction of long-term potentiation or seizure in vivo. We show that Pea3 proteins are expressed in hippocampus in both neuronal and non-neuronal cells, and that Pea3 represses Elk-1 but activates Prkca and Nrcam expression in hippocampal cell lines. We also show that mRNA and protein levels of Pea3 family members are differentially regulated in the dentate gyrus and CA1 region upon MECS stimulation, but not upon LTP induction.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Neurônios/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular , Proteínas de Ligação a DNA/genética , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Transativadores/genética , Fatores de Transcrição/genética , Transcriptoma
15.
J Assist Reprod Genet ; 37(4): 865-873, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32020412

RESUMO

PURPOSE: We evaluated the protective effect of PRP on ovarian function in female rats with cyclophosphamide (Cy)-induced ovarian damage. METHODS: Thirty-two adult female Sprague-Dawley rats were randomly divided into four groups. Group 1 (control-sodium chloride 0.9%; 1 mL/kg, single-dose ip injection), group 2 (Cy); 75 mg/kg, single-dose ip injection and sodium chloride 0.9% (1 mL/kg, single-dose ip injection), group 3 Cy plus PRP, Cy (75 mg/kg, single-dose and PRP (200 µl, single-dose) ip injection), group 4 (PRP, 200 µl, single-dose ip injection). Primordial, antral, and atretic follicle counts; serum anti-Müllerian hormone (AMH) levels; AMH-positive granulosa cells; and gene expression analysis of Ddx4 were assessed. RESULTS: Serum AMH levels were significantly lower in group 2 compared to groups 1, 3, and 4 (p < 0.01, p < 0.01, and p = 0.04, respectively). A significant difference was found in the primordial, primary, secondary, antral, and atretic follicle counts between all groups (p < 0.01). There was a statistically significant difference in AMH-positive staining primary, secondary, and antral follicles count between the groups (p < 0.01). There was a statistically significant difference in primary, secondary, and antral AMH positive staining follicle intensity score between the groups (p < 0.01). Ddx4 expression in group 4 was highest compared to other groups. CONCLUSION: Our study may provide evidence that PRP could protect ovarian function against ovarian damage induced by Cy. It could lead to improved primordial, primary, secondary, and antral follicle numbers.


Assuntos
RNA Helicases DEAD-box/genética , Doenças Ovarianas/tratamento farmacológico , Ovário/metabolismo , Plasma Rico em Plaquetas , Animais , Hormônio Antimülleriano/sangue , Ciclofosfamida/toxicidade , Feminino , Células da Granulosa/metabolismo , Humanos , Doenças Ovarianas/sangue , Doenças Ovarianas/induzido quimicamente , Doenças Ovarianas/patologia , Folículo Ovariano/metabolismo , Ovário/efeitos dos fármacos , Ovário/crescimento & desenvolvimento , Ratos
16.
Sci Rep ; 8(1): 14289, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250150

RESUMO

Beside its unique nutritional content breast milk also contains live cells from the mother. Fate of these cells in the offspring has not been adequately described. In this study, we aimed to detect and identify maternal cells in the suckling's blood and the brain. Green fluorescent protein expressing transgenic female mice (GFP+) were used as foster mothers to breastfeed wildtype newborn pups. One week and two months after the birth, blood samples and brains of the sucklings were analyzed to detect presence of GFP+ cells by fluorescence activated cell sorting, polymerase chain reaction and immunohistochemistry on the brain sections and optically cleared brains. The tests confirmed that maternal cells were detectable in the blood and the brain of the pups and that they differentiated into both neuronal and glial cell types in the brain. This phenomenon represents breastfeeding - induced microchimerism in the brain with functional implications remain to be understood.


Assuntos
Encéfalo/citologia , Leite/citologia , Animais , Animais Recém-Nascidos , Animais Lactentes , Encéfalo/metabolismo , Feminino , Dosagem de Genes , Proteínas de Fluorescência Verde/sangue , Proteínas de Fluorescência Verde/metabolismo , Camundongos Endogâmicos C57BL
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