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1.
BMC Nurs ; 23(1): 36, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38212766

RESUMO

INTRODUCTION: The implementation of Information and Communication Technology (ICT) in daily healthcare practice has become standardized. In relation to education within the nursing degree, ICTs make it possible to carry out practical immersion training from the" classroom or from any other place with an Internet connection, as evidenced by circumstances that have occurred in recent years, such as the pandemic caused by COVID-19. OBJECTIVE: Design and assess a didactic simulation program for the training of the nursing process that promotes learning in the nursing care METHODOLOGY: The methodological approach is quantitative and it is a descriptive cross-sectional study. The sampling method used was non-probabilistic by convenience. RESULTS: When observing the comparison of the averages of student satisfaction with respect to the didactic simulator, it is worth mentioning that all the items are above 2.80 on a score in which "0" is the minimum value and "5" the maximum value. The results of the use of the computer tool by the students, we highlight as significant data that all the items present an average equal to or lower than 3.04 out of 7, where "1" corresponds to a lot of use and "7" to little use. CONCLUSION: The implication of ICT in the teaching-learning process among Nursing Degree students, it is considered optimal. when analyzing the answers obtained in the items that refer to a higher ease in the execution of development of Care plans, a fundamental work in Nursing performance.

2.
Cell Commun Signal ; 22(1): 63, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263049

RESUMO

BACKGROUND: Porcine seminal plasma (SP) is endowed with a heterogeneous population of extracellular vesicles (sEVs). This study evaluated the immunophenotypic profile by high-sensitivity flow cytometry of eight sEV subpopulations isolated according to their size (small [S-sEVs] and large [L-sEVs]) from four different SP sources, namely three ejaculate fractions (the first 10 mL of the sperm rich fraction [SRF-P1], the remaining SRF [SRF-P2], and the post-SRF [PSRF]) and entire ejaculate (EE). METHODS: Seminal EVs were isolated using a size exclusion chromatography-based protocol from six SP pools (five ejaculates/pool) of each SP source and characterized using complementary approaches including total protein (BCA™assay), particle size distribution (dynamic light scattering), morphology (transmission electron microscopy), and purity (albumin by Western blot). Expression of CD9, CD63, CD81, CD44 and HSP90ß was analyzed in all sEV subpopulations by high-sensitivity flow cytometry according to MIFlowCyt-EV guidelines, including an accurate calibration, controls, and discrimination by CFSE-labelling. RESULTS: Each sEV subpopulation exhibited a specific immunophenotypic profile. The percentage of sEVs positive for CD9, CD63, CD81 and HSP90ß differed between S- and L-sEVs (P < 0.0001). Specifically, the percentage of sEVs positive for CD9 and CD63 was higher and that for CD81 was lower in S- than L-sEVs in the four SP sources. However, the percentage of HSP90ß-positive sEVs was lower in S-sEVs than L-sEVs in the SRF-P1 and EE samples. The percentage of sEVs positive for CD9, CD63, and CD44 also differed among the four SP sources (P < 0.0001), being highest in PSRF samples. Notably, virtually all sEV subpopulations expressed CD44 (range: 88.04-98.50%). CONCLUSIONS: This study demonstrated the utility of high-sensitivity flow cytometry for sEV immunophenotyping, allowing the identification of distinct sEV subpopulations that may have different cellular origin, cargo, functions, and target cells.


Assuntos
Vesículas Extracelulares , Sêmen , Masculino , Suínos , Animais , Citometria de Fluxo , Imunofenotipagem , Microscopia Eletrônica de Transmissão
3.
Nucleic Acids Res ; 52(5): 2389-2415, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38224453

RESUMO

DNA damage represents a challenge for cells, as this damage must be eliminated to preserve cell viability and the transmission of genetic information. To reduce or eliminate unscheduled chemical modifications in genomic DNA, an extensive signaling network, known as the DNA damage response (DDR) pathway, ensures this repair. In this work, and by means of a proteomic analysis aimed at studying the STIM1 protein interactome, we have found that STIM1 is closely related to the protection from endogenous DNA damage, replicative stress, as well as to the response to interstrand crosslinks (ICLs). Here we show that STIM1 has a nuclear localization signal that mediates its translocation to the nucleus, and that this translocation and the association of STIM1 to chromatin increases in response to mitomycin-C (MMC), an ICL-inducing agent. Consequently, STIM1-deficient cell lines show higher levels of basal DNA damage, replicative stress, and increased sensitivity to MMC. We show that STIM1 normalizes FANCD2 protein levels in the nucleus, which explains the increased sensitivity of STIM1-KO cells to MMC. This study not only unveils a previously unknown nuclear function for the endoplasmic reticulum protein STIM1 but also expands our understanding of the genes involved in DNA repair.


Assuntos
Núcleo Celular , Dano ao DNA , Molécula 1 de Interação Estromal , Cromatina/genética , Reparo do DNA , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Mitomicina/farmacologia , Proteômica , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismo , Humanos , Núcleo Celular/metabolismo , Proteínas de Neoplasias/metabolismo
4.
Healthcare (Basel) ; 11(14)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37510430

RESUMO

Education in the XXI century is called to move forward in the right direction and to gain momentum to face diverse challenges and take opportunities offered by the knowledge that is inherent in society. Therefore, it can be postulated that there must be a close relationship between learning, the generation of knowledge, continuous innovation and the use of new technologies. This is a cross-sectional descriptive study conducted among a sample of 242 first year and second year Cadiz University nursing students, using the validated Learning and Study Strategies Inventory questionnaire to assess motivation and the Relationship between Learning Styles and Information and Communication Technologies questionnaire to assess knowledge, use and attitude. The predominant profile type of nursing degree students was women under 21 years old, who were single and exclusively dedicated to their studies. In addition, they showed positive motivation in relation to learning while facing adversity (between 76% and 76.6%). Regarding the level of knowledge, use and attitude towards ICTs, most of the considered items presented high values. For some questions, age was proven to be a sociodemographic variable that influenced both the motivation and attitude of the students. The level of knowledge, use and attitude that students have regarding ICTs are good when we refer to communication technologies, interpersonal relationships or basic programs. However, they are low when considering programs related to education or learning.

5.
Healthcare (Basel) ; 11(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37297704

RESUMO

BACKGROUND: During the COVID-19 pandemic, public confrontations between people who had agreed to be vaccinated and those who had not, highlighted the relevance of the deepening dissemination of violent and discriminatory expressions and determined a level of perception of hate discourses. METHOD: A cross-sectional observational study was carried out, based on an innovative methodology: simulations of WhatsApp conversations. In addition, the following variables were considered among others: level of empathy, personality traits and conflict resolution. RESULTS: The participants were 567 nursing students (413 females, 153 males and 1 person who did not identify with any gender). The results showed that, for the most part, the participants correctly identified hate speech, but were unable to discern the frame of reference. CONCLUSIONS: It is necessary to implement intervention strategies to minimize the impact of hate speech, which continues to be used on many levels to harass others, justify violence or undermine rights, generating an environment of prejudice and intolerance that encourages discrimination and violent attacks against certain individuals or collectives.

6.
Healthcare (Basel) ; 11(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36766875

RESUMO

Stress and stressors related to clinical practice are some of the main reasons for the discomfort reported by nursing students. It is important to identify the causes of stress and seek strategies to reduce the stress levels in nursing students. Clinical training seminars have proven to be a useful tool to reduce stress levels. This study aims to evaluate the effects of a series of clinical training seminars on the levels of stress and perception of stress factors before the start of clinical practice among undergraduate Spanish nursing students. A two-phase, sequential mixed-methods design was used. For the quantitative phase, data were collected using Cohen's Perceived Stress Scale and the KEZKAK questionnaire before and after the clinical training seminars. Qualitative data were collected through a focus group session held after the clinical training period. The results show a significant reduction (p = 0.002) in perceived stress levels after the clinical training seminars, and also a change in students' perception of stressors in the clinical placement. This study provides valuable information for the development of content for clinical training seminars. Universities should develop strategies to reduce stress in their students caused by the clinical placement.

7.
Mol Cell Proteomics ; 22(4): 100514, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36796643

RESUMO

Seminal plasma contains many morphologically heterogeneous extracellular vesicles (sEVs). These are sequentially released by cells of the testis, epididymis, and accessory sex glands and involved in male and female reproductive processes. This study aimed to define in depth sEV subsets isolated by ultrafiltration and size exclusion chromatography, decode their proteomic profiles using liquid chromatography-tandem mass spectrometry, and quantify identified proteins using sequential window acquisition of all theoretical mass spectra. The sEV subsets were defined as large (L-EVs) or small (S-EVs) by their protein concentration, morphology, size distribution, and EV-specific protein markers and purity. Liquid chromatography-tandem mass spectrometry identified a total of 1034 proteins, 737 of them quantified by SWATH in S-EVs, L-EVs, and non-EVs-enriched samples (18-20 size exclusion chromatography-eluted fractions). The differential expression analysis revealed 197 differentially abundant proteins between both EV subsets, S-EVs and L-EVs, and 37 and 199 between S-EVs and L-EVs versus non-EVs-enriched samples, respectively. The gene ontology enrichment analysis of differentially abundant proteins suggested, based on the type of protein detected, that S-EVs could be mainly released through an apocrine blebbing pathway and be involved in modulating the immune environment of the female reproductive tract as well as during sperm-oocyte interaction. In contrast, L-EVs could be released by fusion of multivesicular bodies with the plasma membrane becoming involved in sperm physiological processes, such as capacitation and avoidance of oxidative stress. In conclusion, this study provides a procedure capable of isolating subsets of EVs from pig seminal plasma with a high degree of purity and shows differences in the proteomic profile between EV subsets, indicating different sources and biological functions for the sEVs.


Assuntos
Vesículas Extracelulares , Proteoma , Masculino , Feminino , Animais , Suínos , Proteoma/metabolismo , Sêmen/metabolismo , Proteômica/métodos , Vesículas Extracelulares/metabolismo , Espectrometria de Massas
8.
Hum Resour Health ; 18(1): 91, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239035

RESUMO

BACKGROUND: Occupational stress is considered an ongoing epidemic. An inadequate response to a stressful situation can trigger burnout syndrome. In this way, the assistant services (health and teaching) often reach higher levels of burnout. The present study aimed to measure the level of occupational stress and burnout in physiotherapists in the province of Cadiz (Spain), working in the public and/or private sector. METHODS: This was an observational, descriptive and cross-sectional study. A sample of 272 physiotherapists took part in the study. The variables measured were sociodemographic variables, working conditions, level of occupational stress and burnout. Burnout includes three characteristics or dimensions: emotional exhaustion (EE), depersonalization (DP) and personal accomplishment (PA). Correspondence analysis of the sociodemographic, organizational and psychological variables were analyzed using Chi-squared significance tests. Spearman correlations and a linear regression analysis were also carried out to determine the dependence between occupational stress and burnout. RESULTS: The results showed that 30.51% of physiotherapists suffered from a high level of occupational stress, while 34.56% suffered from an average level. There was a clear dependence between a high level of stress and professionals who felt stressed during their academic training period (p = 0.02), those who were in temporary work (p = 0.03) and those with over 10 years of professional experience (p = 0.05). The overall level of burnout was low, since only the EE dimension had a high value; the average was 21.64 ± 10.57. The DP (6.57 ± 4.65) and PA (39.52 ± 5.97) levels were low. There was a significant dependence (p < 0.05) between EE and the following sociodemographic variables: work shift, willingness to study the same degree, stress and inadequate academic training, and a stressful job. In addition, a significant correlation was found between occupational stress and the EE and DP dimensions of burnout. CONCLUSIONS: A high prevalence of occupational stress was detected among physiotherapists in Cadiz (Spain). The levels of occupational stress and its correlation with burnout show that the cumulative effect of stress could lead to burnout. Furthermore, these results regarding occupational stress show the necessity of developing coping strategies for physiotherapists and healthcare staff.


Assuntos
Esgotamento Profissional , Estresse Ocupacional , Fisioterapeutas , Esgotamento Profissional/epidemiologia , Estudos Transversais , Humanos , Estresse Ocupacional/epidemiologia , Espanha/epidemiologia , Inquéritos e Questionários
9.
Nutrients ; 11(11)2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31684076

RESUMO

Anomalous immune/inflammatory responses in obesity take place along with alterations in the neuroendocrine responses and dysregulation in the immune/stress feedback mechanisms. Exercise is a potential anti-inflammatory strategy in this context, but the influence of exercise on the ß2 adrenergic regulation of the monocyte-mediated inflammatory response in obesity remains completely unknown. The first objective of this study was to analyze the effect of exercise on the inflammatory profile and phenotype of monocytes from obese and lean animals, and the second aim was to determine whether obesity could affect monocytes' inflammatory response to ß2 adrenergic activation in exercised animals. C57BL/6J mice were allocated to different lean or obese groups: sedentary, with acute exercise, or with regular exercise. The inflammatory profile and phenotype of their circulating monocytes were evaluated by flow cytometry in the presence or absence of the selective ß2 adrenergic receptor agonist terbutaline. Exercise caused an anti-inflammatory effect in obese individuals and a pro-inflammatory effect in lean individuals. ß2 adrenergic receptor stimulation exerted a global pro-inflammatory effect in monocytes from exercised obese animals and an anti-inflammatory effect in monocytes from exercised lean animals. Thus, ß2 adrenergic regulation of inflammation in monocytes from exercised animals seems to depend on the inflammatory basal set-point.


Assuntos
Citocinas/metabolismo , Monócitos/metabolismo , Obesidade/metabolismo , Condicionamento Físico Animal/fisiologia , Receptores Adrenérgicos beta 2/metabolismo , Animais , Citocinas/análise , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/efeitos dos fármacos , Terbutalina/farmacologia
10.
Sci Rep ; 9(1): 11584, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399634

RESUMO

Seminal extracellular vesicles (EVs) include exosomes (ø 40-120 nm) and microvesicles (MVs, ø 120-1000 nm), which would be involved in multiple functional reproductive roles. The study aimed to establish which EV subtypes are present in pig semen, using a high-resolution flow cytometer to explore differences in their tetraspanin expression profile. The EVs were isolated from 12 pig ejaculates using serial ultracentrifugation and characterized by dynamic light scattering and electron microscopy for size and morphology as well as for tetraspanin expression using flow cytometry with Carboxyfluorescein succinimidyl ester (CFSE) and antibodies against CD9, CD63 and CD81. Pig semen contained a heterogeneous EV-population regarding size and morphology. Flow cytometric analysis demonstrated that the proportion of EVs expressing CD63 and CD9 was higher in MVs (P < 0.001 and P < 0.05, respectively) than in exosomes, while the opposite was true for CD81; higher (P < 0.001) in exosomes than in MVs. In conclusion, (1) the new generation of flow cytometers are able to accurately identify EVs and to gate them in two size-different populations named exosomes and MVs. (2) Tetraspanins CD9, CD63 and CD81 are present in both seminal EVs, albeit with exosomes and MVs differing in expression profiles, suggesting dissimilar cargo and binding affinity.


Assuntos
Vesículas Extracelulares/química , Sêmen/química , Suínos , Tetraspaninas/análise , Animais , Exossomos/química , Exossomos/ultraestrutura , Vesículas Extracelulares/ultraestrutura , Citometria de Fluxo , Masculino , Suínos/metabolismo , Tetraspanina 28/análise , Tetraspanina 29/análise , Tetraspanina 30/análise
12.
PLoS One ; 14(6): e0213420, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31237882

RESUMO

Artificial insemination with cryopreserved spermatozoa is a major assisted reproductive technology in many species. In horses, as in humans, insemination with cryopreserved sperm is associated with lower pregnancy rates than those for fresh sperm, however, direct effects of sperm cryopreservation on the development of resulting embryos are largely unexplored. The aim of this study was to investigate differences in gene expression between embryos resulting from fertilization with fresh or cryopreserved sperm. Embryos were obtained at 8, 10 or 12 days after ovulation from mares inseminated post-ovulation on successive cycles with either fresh sperm or frozen-thawed sperm from the same stallion, providing matched embryo pairs at each day. RNA was isolated from two matched pairs (4 embryos) for each day, and cDNA libraries were built and sequenced. Significant differences in transcripts per kilobase million (TPM) were determined using (i) genes for which the expression difference between treatments was higher than 99% of that in the random case (P < 0.01), and (ii) genes for which the fold change was ≥ 2, to avoid expression bias in selection of the candidate genes. Molecular pathways were explored using the DAVID webserver, followed by network analyses using STRING, with a threshold of 0.700 for positive interactions. The transcriptional profile of embryos obtained with frozen-thawed sperm differed significantly from that for embryos derived from fresh sperm on all days, showing significant down-regulation of genes involved in biological pathways related to oxidative phosphorylation, DNA binding, DNA replication, and immune response. Many genes with reduced expression were orthologs of genes known to be embryonic lethal in mice. This study, for the first time, provides evidence of altered transcription in embryos resulting from fertilization with cryopreserved spermatozoa in any species. As sperm cryopreservation is commonly used in many species, including human, the effect of this intervention on expression of developmentally important genes in resulting embryos warrants attention.


Assuntos
Desenvolvimento Embrionário/genética , Perfilação da Expressão Gênica , Inseminação Artificial/métodos , Preservação do Sêmen/veterinária , Animais , Criopreservação/veterinária , Regulação para Baixo , Embrião de Mamíferos , Feminino , Cavalos , Inseminação Artificial/veterinária , Masculino , Preservação do Sêmen/efeitos adversos
13.
Brain Behav Immun ; 80: 564-572, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31055173

RESUMO

Obesity is a chronic condition associated with low-grade inflammation, and it also involves alterations of the function of the hypothalamic-pituitaryadrenal axis and the sympathetic nervous system. Adrenergic agonists such as catecholamines are important immunoregulatory molecules that are involved in modulating both metabolism and most of the mechanisms of the immune response. The first objective of this study was to determine whether the systemic inflammatory state associated with obesity is also manifested in the inflammatory profile and phenotype of circulating monocytes; and the second objective was to evaluate the effects of ß2 adrenergic stimulation on the inflammatory profile and phenotype of monocytes in obesity, and whether this response could be different from that in lean individuals. C57BL/6J mice were randomly allocated to one of two diets for 18 weeks: high-fat diet in order to obtain an experimental model of obesity, and standard diet in the control lean group. Circulating monocyte expression of inflammatory cytokines (MCP-1, TNF-α, IL-8, IL-6, IL-10, and TGF-ß), surface membrane marker Ly6C, inducible nitric oxide synthase and arginase-1, and Toll-like receptor 4 were evaluated through flow cytometry in the presence or absence of selective ß2 adrenergic receptor agonist terbutaline. Monocytes from high-fat diet-induced obese animals presented higher expression levels of all pro-inflammatory cytokines and a higher percentage of monocytes with a pro-inflammatory phenotype than those from lean animals. ß2 adrenergic stimulation induced a shift towards an anti-inflammatory activity profile and phenotype in obese mice, whereas it induced a shift towards a pro-inflammatory activity profile and phenotype in lean mice. In conclusion, ß2 adrenergic stimulation in monocytes was anti-inflammatory only in obese animals, which presented a pro-inflammatory state at baseline.


Assuntos
Monócitos/metabolismo , Obesidade/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Animais , Quimiocina CCL2/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Epinefrina/metabolismo , Feminino , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-10/metabolismo , Masculino , Síndrome Metabólica/imunologia , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Norepinefrina/metabolismo , Obesidade/fisiopatologia , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Development ; 145(23)2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30389850

RESUMO

In vertebrates, planar polarization of ciliary basal bodies has been associated with actin polymerization that occurs downstream of the Frizzled-planar cell polarity (Fz-PCP) pathway. In Drosophila wing epithelial cells, which do not have cilia, centrioles also polarize in a Fz-PCP-dependent manner, although the relationship with actin polymerization remains unknown. By combining existing and new quantitative methods, we unexpectedly found that known PCP effectors linked to actin polymerization phenotypes affect neither final centriole polarization nor apical centriole distribution. But actin polymerization is required upstream of Fz-PCP to maintain the centrioles in restricted areas in the apical-most planes of those epithelial cells before and after the actin-based hair is formed. Furthermore, in the absence of proper core Fz-PCP signalling, actin polymerization is insufficient to drive this off-centred centriole migration. Altogether, the results reveal that there are at least two pathways controlling centriole positioning in Drosophila pupal wings - an upstream actin-dependent mechanism involved in centriole distribution that is PCP independent, and an unknown mechanism that links core Fz-PCP and centriole polarization.


Assuntos
Polaridade Celular , Centríolos/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Asas de Animais/citologia , Asas de Animais/metabolismo , Actinas/metabolismo , Animais , Polaridade Celular/efeitos dos fármacos , Centríolos/efeitos dos fármacos , Citocalasina D/farmacologia , Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Mutação com Ganho de Função/genética , Mutação com Perda de Função/genética , Fenótipo , Polimerização
15.
iScience ; 4: 44-63, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30240752

RESUMO

Aryl hydrocarbon receptor (AhR) deficiency alters tissue homeostasis. However, how AhR regulates organ maturation and differentiation remains mostly unknown. Liver differentiation entails a polyploidization process fundamental for cell growth, metabolism, and stress responses. Here, we report that AhR regulates polyploidization during the preweaning-to-adult mouse liver maturation. Preweaning AhR-null (AhR-/-) livers had smaller hepatocytes, hypercellularity, altered cell cycle regulation, and enhanced proliferation. Those phenotypes persisted in adult AhR-/- mice and correlated with compromised polyploidy, predominance of diploid hepatocytes, and enlarged centrosomes. Phosphatidylinositol-3-phosphate kinase (PI3K), extracellular signal-regulated kinase (ERK), and Wnt/ß-catenin signaling remained upregulated from preweaning to adult AhR-null liver, likely increasing mammalian target of rapamycin (mTOR) activation. Metabolomics revealed the deregulation of mitochondrial oxidative phosphorylation intermediates succinate and fumarate in AhR-/- liver. Consistently, PI3K, ERK, and Wnt/ß-catenin inhibition partially rescued polyploidy in AhR-/- mice. Thus, AhR may integrate survival, proliferation, and metabolism for liver polyploidization. Since tumor cells tend to be polyploid, AhR modulation could have therapeutic value in the liver.

16.
J Mol Med (Berl) ; 96(10): 1061-1079, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30088035

RESUMO

STIM1 is an endoplasmic reticulum protein with a role in Ca2+ mobilization and signaling. As a sensor of intraluminal Ca2+ levels, STIM1 modulates plasma membrane Ca2+ channels to regulate Ca2+ entry. In neuroblastoma SH-SY5Y cells and in familial Alzheimer's disease patient skin fibroblasts, STIM1 is cleaved at the transmembrane domain by the presenilin-1-associated γ-secretase, leading to dysregulation of Ca2+ homeostasis. In this report, we investigated expression levels of STIM1 in brain tissues (medium frontal gyrus) of pathologically confirmed Alzheimer's disease patients, and observed that STIM1 protein expression level decreased with the progression of neurodegeneration. To study the role of STIM1 in neurodegeneration, a strategy was designed to knock-out the expression of STIM1 gene in the SH-SY5Y neuroblastoma cell line by CRISPR/Cas9-mediated genome editing, as an in vitro model to examine the phenotype of STIM1-deficient neuronal cells. It was proved that, while STIM1 is not required for the differentiation of SH-SY5Y cells, it is absolutely essential for cell survival in differentiating cells. Differentiated STIM1-KO cells showed a significant decrease of mitochondrial respiratory chain complex I activity, mitochondrial inner membrane depolarization, reduced mitochondrial free Ca2+ concentration, and higher levels of senescence as compared with wild-type cells. In parallel, STIM1-KO cells showed a potentiated Ca2+ entry in response to depolarization, which was sensitive to nifedipine, pointing to L-type voltage-operated Ca2+ channels as mediators of the upregulated Ca2+ entry. The stable knocking-down of CACNA1C transcripts restored mitochondrial function, increased mitochondrial Ca2+ levels, and dropped senescence to basal levels, demonstrating the essential role of the upregulation of voltage-operated Ca2+ entry through Cav1.2 channels in STIM1-deficient SH-SY5Y cell death. KEY MESSAGES: STIM1 protein expression decreases with the progression of neurodegeneration in Alzheimer's disease. STIM1 is essential for cell viability in differentiated SH-SY5Y cells. STIM1 deficiency triggers voltage-regulated Ca2+ entry-dependent cell death. Mitochondrial dysfunction and senescence are features of STIM1-deficient differentiated cells.


Assuntos
Doença de Alzheimer/genética , Canais de Cálcio Tipo L/fisiologia , Cálcio/fisiologia , Proteínas de Neoplasias/fisiologia , Molécula 1 de Interação Estromal/fisiologia , Idoso , Idoso de 80 Anos ou mais , Morte Celular , Linhagem Celular Tumoral , Humanos , Córtex Pré-Frontal/fisiologia
20.
Stem Cell Res ; 25: 61-71, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29107893

RESUMO

Recent experimental evidences from cellular systems and from mammalian and non-mammalian animal models highlight novel functions for the aryl hydrocarbon/dioxin receptor (AhR) in maintaining cell differentiation and tissue homeostasis. Notably, AhR depletion stimulates an undifferentiated and pluripotent phenotype likely associated to a mesenchymal transition in epithelial cells and to increased primary tumorigenesis and metastasis in melanoma. In this work, we have used a lung model of epithelial regeneration to investigate whether AhR regulates proper tissue repair by adjusting the expansion of undifferentiated stem-like cells. AhR-null mice developed a faster and more efficient repair of the lung bronchiolar epithelium upon naphthalene injury that required increased cell proliferation and the earlier activation of stem-like Clara, Basal and neuroepithelial cells precursors. Increased basal content in multipotent Sca1+/CD31-/CD4- cells and in cells expressing pluripotency factors NANOG and OCT4 could also improve re-epithelialization in AhR-null lungs. The reduced response of AhR-deficient lungs to Sonic Hedgehog (Shh) repression shortly after injury may also help their improved bronchiolar epithelium repair. These results support a role for AhR in the regenerative response against toxins, and open the possibility of modulating its activation level to favor recovery from lesions caused by environmental contaminants.


Assuntos
Pulmão/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Camundongos , Naftalenos/toxicidade , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Hidrocarboneto Arílico/genética
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