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1.
J Appl Microbiol ; 134(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307226

RESUMO

AIMS: Isolation and characterization of lactobacilli from human milk and determination of their probiotic, technological, and in vitro health-promoting properties with a view to their potential use in food fermentation. METHODS AND RESULTS: Seven lactobacilli isolates were obtained from human milk and identified as Lacticaseibacillus paracasei (isolates BM1-BM6) and Lactobacillus gasseri (BM7). The isolates were examined in vitro for their technological, probiotic, and health-promoting potential. Overall, all isolates showed important technological properties based on the ability to grow in milk whey, a high to moderate acidification capacity and the absence of undesirable enzymatic activities. Lacticaseibacillus gasseri (BM7) differed from the L. paracasei isolates by the absence of several glycosidases and the inability to ferment lactose. Isolates L. paracasei BM3 and BM5 produced exopolysaccharides (EPS) from lactose. All isolates showed probiotic potential as they were tolerant to simulated gastrointestinal conditions, had high cell surface hydrophobicity, had not acquired resistance to relevant antibiotics and had no virulence characteristics. All L. paracasei showed high antimicrobial activity against various pathogenic bacteria and fungi, while L. gasseri showed a narrower spectrum of antimicrobial activity. All isolates showed health-promoting potential in vitro, as evidenced by high cholesterol-lowering activity, high ACE inhibitory activity and marked antioxidant activity. CONCLUSIONS: All strains showed excellent probiotic and technological properties for use in lactic ferments.


Assuntos
Lacticaseibacillus paracasei , Probióticos , Feminino , Humanos , Animais , Lactobacillus , Leite/microbiologia , Leite Humano , Lactose , Probióticos/farmacologia
2.
J Cell Mol Med ; 25(2): 1314-1318, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33300293

RESUMO

The aim of this study is to evaluate whether the alterations in glucose metabolism and insulin resistance are mechanisms presented in cardiac remodelling induced by the toxicity of cigarette smoke. Male Wistar rats were assigned to the control group (C; n = 12) and the cigarette smoke-exposed group (exposed to cigarette smoke over 2 months) (CS; n = 12). Transthoracic echocardiography, blood pressure assessment, serum biochemical analyses for catecholamines and cotinine, energy metabolism enzymes activities assay; HOMA index (homeostatic model assessment); immunohistochemistry; and Western blot for proteins involved in energy metabolism were performed. The CS group presented concentric hypertrophy, systolic and diastolic dysfunction, and higher oxidative stress. It was observed changes in energy metabolism, characterized by a higher HOMA index, lower concentration of GLUT4 (glucose transporter 4) and lower 3-hydroxyl-CoA dehydrogenase activity, suggesting the presence of insulin resistance. Yet, the cardiac glycogen was depleted, phosphofructokinase (PFK) and lactate dehydrogenase (LDH) increased, with normal pyruvate dehydrogenase (PDH) activity. The activity of citrate synthase, mitochondrial complexes and ATP synthase (adenosine triphosphate synthase) decreased and the expression of Sirtuin 1 (SIRT1) increased. In conclusion, exposure to cigarette smoke induces cardiac remodelling and dysfunction. The mitochondrial dysfunction and heart damage induced by cigarette smoke exposure are associated with insulin resistance and glucose metabolism changes.


Assuntos
Glucose/metabolismo , Resistência à Insulina , Fumar/efeitos adversos , Remodelação Ventricular , Animais , Catecolaminas/sangue , Cotinina/sangue , Eletrocardiografia , Metabolismo Energético , Masculino , Estresse Oxidativo , Ratos Wistar
3.
EMBO Rep ; 20(10): e48019, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31456285

RESUMO

Xist RNA has been established as the master regulator of X-chromosome inactivation (XCI) in female eutherian mammals, but its mechanism of action remains unclear. By creating novel Xist-inducible mutants at the endogenous locus in male mouse embryonic stem (ES) cells, we dissect the role of the conserved A-B-C-F repeats in the initiation of XCI. We find that transcriptional silencing can be largely uncoupled from Polycomb repressive complex 1 and complex 2 (PRC1/2) recruitment, which requires B and C repeats. Xist ΔB+C RNA specifically loses interaction with PCGF3/5 subunits of PRC1, while binding of other Xist partners is largely unaffected. However, a slight relaxation of transcriptional silencing in Xist ΔB+C indicates a role for PRC1/2 proteins in early stabilization of gene repression. Distinct modules within the Xist RNA are therefore involved in the convergence of independent chromatin modification and gene repression pathways. In this context, Polycomb recruitment seems to be of moderate relevance in the initiation of silencing.


Assuntos
Proteínas do Grupo Polycomb/metabolismo , RNA Longo não Codificante/metabolismo , Inativação do Cromossomo X/genética , Animais , Feminino , Histonas/metabolismo , Lisina/metabolismo , Metilação , Camundongos , Modelos Genéticos , Mutação/genética , Mapas de Interação de Proteínas , Sequências Repetitivas de Ácido Nucleico/genética , Transcrição Gênica , Cromossomo X/genética
4.
Breast Cancer Res ; 18(1): 71, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27456846

RESUMO

BACKGROUND: Although males contribute half of the embryo's genome, only recently has interest begun to be directed toward the potential impact of paternal experiences on the health of offspring. While there is evidence that paternal malnutrition may increase offspring susceptibility to metabolic diseases, the influence of paternal factors on a daughter's breast cancer risk has been examined in few studies. METHODS: Male Sprague-Dawley rats were fed, before and during puberty, either a lard-based (high in saturated fats) or a corn oil-based (high in n-6 polyunsaturated fats) high-fat diet (60 % of fat-derived energy). Control animals were fed an AIN-93G control diet (16 % of fat-derived energy). Their 50-day-old female offspring fed only a commercial diet were subjected to the classical model of mammary carcinogenesis based on 7,12-dimethylbenz[a]anthracene initiation, and mammary tumor development was evaluated. Sperm cells and mammary gland tissue were subjected to cellular and molecular analysis. RESULTS: Compared with female offspring of control diet-fed male rats, offspring of lard-fed male rats did not differ in tumor latency, growth, or multiplicity. However, female offspring of lard-fed male rats had increased elongation of the mammary epithelial tree, number of terminal end buds, and tumor incidence compared with both female offspring of control diet-fed and corn oil-fed male rats. Compared with female offspring of control diet-fed male rats, female offspring of corn oil-fed male rats showed decreased tumor growth but no difference regarding tumor incidence, latency, or multiplicity. Additionally, female offspring of corn oil-fed male rats had longer tumor latency as well as decreased tumor growth and multiplicity compared with female offspring of lard-fed male rats. Paternal consumption of animal- or plant-based high-fat diets elicited opposing effects, with lard rich in saturated fatty acids increasing breast cancer risk in offspring and corn oil rich in n-6 polyunsaturated fatty acids decreasing it. These effects could be linked to alterations in microRNA expression in fathers' sperm and their daughters' mammary glands, and to modifications in breast cancer-related protein expression in this tissue. CONCLUSIONS: Our findings highlight the importance of paternal nutrition in affecting future generations' risk of developing breast cancer.


Assuntos
Neoplasias da Mama/etiologia , Exposição Paterna , Efeitos Tardios da Exposição Pré-Natal , Animais , Apoptose , Neoplasias da Mama/patologia , Proliferação de Células , Transformação Celular Neoplásica , Análise por Conglomerados , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Humanos , Lipídeos/química , Masculino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Animais , Neoplasias Mamárias Experimentais , Carne , MicroRNAs , Plantas/química , Gravidez , Proteômica/métodos , Ratos , Espermatozoides/metabolismo
5.
Int J Cancer ; 139(8): 1873-82, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27270969

RESUMO

Breast cancer is a global public health problem and accumulating evidence indicates early-life exposures as relevant factors in the disease risk determination. Recent studies have shown that paternal nutrition can influence offspring health including breast cancer risk. Selenium is a micronutrient with essential role in central aspects of embryogenesis, male fertility and cancer and that has been extensively studied as a chemopreventive agent in several breast cancer experimental models. Thus, we designed an animal study to evaluate whether paternal selenium deficiency or supplementation during preconception could affect the female offspring mammary gland development and breast cancer susceptibility. Male Sprague-Dawley rats were fed AIN93-G diet containing 0.15 ppm (control diet), 0.05 ppm (deficient diet) or 1 ppm (supplemented diet) of selenium for 9 weeks and mated with control female rats. Mammary carcinogenesis was induced with 7,12-dimethylbenz[a]anthracene (DMBA) in their female offspring. Paternal selenium deficiency increased the number of terminal end buds, epithelial elongation and cell proliferation in the mammary gland of the female rat offspring and these effects were associated with higher susceptibility to DMBA-induced mammary tumors (increased incidence and higher grade tumors). On the other hand, paternal selenium supplementation did not influence any of these parameters. These results highlight the importance of father's nutrition including selenium status as a relevant factor affecting daughter's breast cancer risk and paternal preconception as a potential developmental stage to start disease preventive strategies.


Assuntos
Neoplasias Mamárias Experimentais/etiologia , Selênio/administração & dosagem , Selênio/deficiência , 9,10-Dimetil-1,2-benzantraceno , Animais , Carcinogênese , Suplementos Nutricionais , Feminino , Masculino , Glândulas Mamárias Animais/crescimento & desenvolvimento , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Ratos , Ratos Sprague-Dawley
6.
Br J Nutr ; 110(11): 2020-9, 2013 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23656754

RESUMO

The aim of the present study was to investigate the effects of long-term grape juice concentrate (GJC) consumption, in two dosages, on the reproductive parameters of cadmium-exposed male rats. The effects of the concentrate on body mass gain, plasma testosterone levels, reproductive organ weights, daily sperm production, sperm morphology, testis histopathological and histomorphometrical parameters, and testicular antioxidant markers were investigated. Wistar rats (n 54) were distributed into six groups: CdCl2; cadmium and grape juice I (1·18 g/kg per d); cadmium and grape juice II (2·36 g/kg per d); grape juice I (1·18 g/kg per d); grape juice II (2·36 g/kg per d); control. A single dose of CdCl2 (1·2 mg/kg body weight (BW)) was injected intraperitoneally and the grape juice was administered orally for 56 d. The results indicated that cadmium changed all reproductive and antioxidant parameters. At dosage I (1·18 g/kg BW), GJC consumption did not show the effects against cadmium-induced damages. In contrast, at dosage II (2·36 g/kg BW), the GJC improved the gonadosomatic index (P= 0·003), serum testosterone levels (P= 0·001), the relative weight of epididymis (P= 0·013) and ventral prostate (P= 0·052), the percentage of normal sperm (P= 0·001), and histopathological and histomorphometrical parameters. In addition, at this dosage, normalisation of the enzymatic activity of superoxide dismutase (P= 0·001) and of testicular levels of glutathione (P= 0·03) were observed. The parameters of the non-exposed rats did not depict significant alterations. In conclusion, the product was able to act as a protector of reproductive function against cadmium-induced damage. Such a property was expressed in a dose-dependent manner as the more effective dose was dosage II. The GJC acted possibly by antioxidant mechanisms.


Assuntos
Bebidas , Intoxicação por Cádmio/fisiopatologia , Frutas , Alimento Funcional , Infertilidade Masculina/prevenção & controle , Substâncias Protetoras/uso terapêutico , Vitis , Animais , Cloreto de Cádmio/antagonistas & inibidores , Cloreto de Cádmio/toxicidade , Epididimo/efeitos dos fármacos , Epididimo/imunologia , Epididimo/patologia , Manipulação de Alimentos , Glutationa/metabolismo , Infertilidade Masculina/etiologia , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/imunologia , Próstata/patologia , Substâncias Protetoras/administração & dosagem , Distribuição Aleatória , Ratos , Ratos Wistar , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/imunologia , Testículo/metabolismo , Testículo/patologia , Testosterona/sangue
7.
Cell Rep ; 42(2): 112077, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36729832

RESUMO

At critically short telomeres, stabilized TERRA RNA-DNA hybrids drive homology-directed repair (HDR) to delay replicative senescence. However, even at long- and intermediate-length telomeres, not subject to HDR, transient TERRA RNA-DNA hybrids form, suggestive of additional roles. We report that telomeric RNA-DNA hybrids prevent Exo1-mediated resection when telomeres become non-functional. We used the well-characterized cdc13-1 allele, where telomere resection can be induced in a temperature-dependent manner, to demonstrate that ssDNA generation at telomeres is either prevented or augmented when RNA-DNA hybrids are stabilized or destabilized, respectively. The viability of cdc13-1 cells is affected by the presence or absence of hybrids accordingly. Telomeric hybrids do not affect the shortening rate of bulk telomeres. We suggest that TERRA hybrids require dynamic regulation to drive HDR at short telomeres; hybrid presence may initiate HDR through replication stress, whereby their removal allows strand resection.


Assuntos
RNA , Telômero , RNA/genética , Telômero/genética , DNA , Encurtamento do Telômero , DNA de Cadeia Simples
8.
Genetics ; 224(4)2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37259670

RESUMO

Gamete formation is essential for sexual reproduction in metazoans. Meiosis in males gives rise to spermatids that must differentiate and individualize into mature sperm. In Drosophila melanogaster, individualization of interconnected spermatids requires the formation of individualization complexes that synchronously move along the sperm bundles. Here, we show that Mob4, a member of the Mps-one binder family, is essential for male fertility but has no detectable role in female fertility. We show that Mob4 is required for proper axonemal structure and its loss leads to male sterility associated with defective spermatid individualization and absence of mature sperm in the seminal vesicles. Transmission electron micrographs of developing spermatids following mob4RNAi revealed expansion of the outer axonemal microtubules such that the 9 doublets no longer remained linked to each other and defective mitochondrial organization. Mob4 is a STRIPAK component, and male fertility is similarly impaired upon depletion of the STRIPAK components, Strip and Cka. Expression of the human Mob4 gene rescues all phenotypes of Drosophila mob4 downregulation, indicating that the gene is evolutionarily and functionally conserved. Together, this suggests that Mob4 contributes to the regulation of the microtubule- and actin-cytoskeleton during spermatogenesis through the conserved STRIPAK complex. Our study advances the understanding of male infertility by uncovering the requirement for Mob4 in sperm individualization.


Assuntos
Proteínas de Drosophila , Infertilidade Masculina , Animais , Feminino , Humanos , Masculino , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Infertilidade Masculina/genética , Proteínas do Tecido Nervoso/metabolismo , Sêmen/metabolismo , Espermátides/metabolismo , Espermatogênese/genética , Testículo/metabolismo
9.
Life Sci Alliance ; 6(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37468166

RESUMO

Fun30 is the prototype of the Fun30-SMARCAD1-ETL subfamily of nucleosome remodelers involved in DNA repair and gene silencing. These proteins appear to act as single-subunit nucleosome remodelers, but their molecular mechanisms are, at this point, poorly understood. Using multiple sequence alignment and structure prediction, we identify an evolutionarily conserved domain that is modeled to contain a SAM-like fold with one long, protruding helix, which we term SAM-key. Deletion of the SAM-key within budding yeast Fun30 leads to a defect in DNA repair and gene silencing similar to that of the fun30Δ mutant. In vitro, Fun30 protein lacking the SAM-key is able to bind nucleosomes but is deficient in DNA-stimulated ATPase activity and nucleosome sliding and eviction. A structural model based on AlphaFold2 prediction and verified by crosslinking-MS indicates an interaction of the long SAM-key helix with protrusion I, a subdomain located between the two ATPase lobes that is critical for control of enzymatic activity. Mutation of the interaction interface phenocopies the domain deletion with a lack of DNA-stimulated ATPase activation and a nucleosome-remodeling defect, thereby confirming a role of the SAM-key helix in regulating ATPase activity. Our data thereby demonstrate a central role of the SAM-key domain in mediating the activation of Fun30 catalytic activity, thus highlighting the importance of allosteric activation for this class of enzymes.


Assuntos
Nucleossomos , Proteínas de Saccharomyces cerevisiae , Nucleossomos/genética , Nucleossomos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , DNA/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo
10.
Front Mol Biosci ; 9: 889971, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813817

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive and common form of glioma. GBM, like many other tumors, expresses high levels of redox proteins, such as thioredoxin (Trx) and thioredoxin reductase (TrxR), allowing tumor cells to cope with high levels of reactive oxygen species (ROS) and resist chemotherapy and radiotherapy. Thus, tackling the activity of these enzymes is a strategy to reduce cell viability and proliferation and most importantly achieve tumor cell death. Mercury (Hg) compounds are among the most effective inhibitors of TrxR and Trx due to their high affinity for binding thiols and selenols. Moreover, organomercurials such as thimerosal, have a history of clinical use in humans. Thimerosal effectively crosses the blood-brain barrier (BBB), thus reaching effective concentrations for the treatment of GBM. Therefore, this study evaluated the effects of thimerosal (TmHg) and its metabolite ethylmercury (EtHg) over the mouse glioma cell line (GL261), namely, the inhibition of the thioredoxin system and the occurrence of oxidative cellular stress. The results showed that both TmHg and EtHg increased oxidative events and triggered cell death primarily by apoptosis, leading to a significant reduction in GL261 cell viability. Moreover, the cytotoxicity of TmHg and ETHg in GL261 was significantly higher when compared to temozolomide (TMZ). These results indicate that EtHg and TmHg have the potential to be used in GBM therapy since they strongly reduce the redox capability of tumor cells at exceedingly low exposure levels.

11.
Rev Saude Publica ; 55: 63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34706039

RESUMO

OBJECTIVE: To describe feeding practices and the risk factors for the mixed breastfeeding and early weaning in the neonatal period. METHODS: Cohort study, which we collected socioeconomic, demographic, health care and feeding data from 415 mother/child binomials born in four public maternity hospitals in Natal/Brazil. They were followed-up at 48 hours, 7 and 28 days after birth. The association was established using Pearson's Chi-square test and Poisson's regression, after adjusting it to other variables. RESULTS: The prevalence of mixed breastfeeding in the first 2 days was 47,2% and early weaning in 7 and 28 days was 8,4% and 16,2% in that order. The main reasons for mixed breastfeeding and early weaning were: colostrum deficiency (33.8%), difficulty in latching/sucking (23.5%) and "little milk" (70.0%). The use of formula/milk/porridge remained associated with maternal age ≤ 20 years (RR = 0.64; 95%CI: 0.47-0.86), age 20-29 years (RR = 0,70; 95%CI: 0,57-0,87), primiparity (RR = 1.37; 95%CI: 1.11-1.60) and cesarean delivery (RR = 1.20; 95%CI: 1.00-1.45) at 2 days; absence of paternal support (RR = 4.98; 95%CI: 2.54-9.79) and pacifier use (RR = 3.21; 95%CI: 1.63-6.32) at 7 days; and only pacifier use (RR = 2.48; 95%CI: 1.53-4.02) at 28 days. CONCLUSIONS: Early weaning was associated with maternal and health care factors, thus suggesting the need to readjust good practices and educational actions to achieve the exclusive offer to the maternal breast in the neonatal period.


Assuntos
Aleitamento Materno , Adulto , Brasil/epidemiologia , Criança , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Idade Materna , Gravidez , Desmame , Adulto Jovem
12.
Clin Diabetes Endocrinol ; 7(1): 2, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402217

RESUMO

BACKGROUND: We intended to estimate the proportion hypoglycemic/hyperglycemic emergency episodes in treated diabetes mellitus (DM) patients admitted to a hospital ward, and calculate the prevalence of risk factors for hypoglycemia and diabetic complications. METHODS: In this cross-sectional, multicentered study, the observational data was collected by physicians from patient's hospitalization to discharge/death. Statistical tests were 2-tailed considering 5% significance level. RESULTS: There were 646 ward admissions due to hyperglycemic emergencies and 176 hypoglycemic episodes with a ratio hypoglycemia/hyperglycemia 0.27 for all DM patients. In T2DM patients the ratio was 0.38. These were mainly female (55.1%), functionally dependent (61.4%) and retired/disabled (73.1%). Median age was 75 years and median duration of disease 11 years. Half the patients were on insulin-based therapy and 30.1% on secretagogue-based therapy. Approximately 57% of patients needed occasional/full assistance to manage the disease. The most frequent risk factor for hypoglycemia was polypharmacy (85.0%). Hypoglycemia in the 12 months before admission was higher in insulin-based therapy patients (66.1%; p = 0.001). CONCLUSIONS: Hyperglycemic emergencies are the most frequent cause of hospitalization in Portugal, although severe hypoglycemic events represent a health and social problem in elderly/frail patients. There is still the need to optimize therapy in terms of the potential for hypoglycemia in this patient group and a review of anti-hyperglycemic agents to add on to insulin.

13.
Arq Bras Cardiol ; 116(5): 970-978, 2021 05.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34008824

RESUMO

BACKGROUND: Vitamin D (VD) has been shown to play an important role in cardiac function. However, this vitamin exerts a biphasic "dose response" curve in cardiovascular pathophysiology and may cause deleterious effects, even in non-toxic doses. VD exerts its cellular functions by binding to VD receptor. Additionally, it was identified that the thioredoxin-interacting protein (TXNIP) expression is positively regulated by VD. TXNIP modulate different cell signaling pathways that may be important for cardiac remodeling. OBJECTIVE: To evaluate whether VD supplementation lead to cardiac remodeling and if TXNIP and thioredoxin (Trx) proteins are associated with the process. METHODS: A total of 250 Male Wistar rats were allocated into three groups: control (C, n=21), with no VD supplementation; VD3 (n = 22) and VD10 (n=21), supplemented with 3,000 and 10,000 IU of VD/ kg of chow respectively, for two months. The groups were compared by one-way analysis of variance (ANOVA) and Holm-Sidak post hoc analysis, (variables with normal distribution), or by Kruskal-Wallis test and Dunn's test post hoc analysis. The significance level for all tests was 5%. RESULTS: TXNIP protein expression was higher and Trx activity was lower in VD10. The animals supplemented with VD showed increased lipid hydroperoxide and decreased superoxide dismutase and glutathione peroxidase. The protein Bcl-2 was lower in VD10. There was a decrease in fatty acid ß-oxidation, tricarboxylic acid cycle and electron transport chain with shift to increase in glycolytic pathway. CONCLUSION: VD supplementation led to cardiac remodeling and this process may be modulated by TXNIP and Trx proteins and consequently oxidative stress.


FUNDAMENTO: A vitamina D (VD) tem um importante papel na função cardíaca. No entanto, a vitamina exerce uma curva "dose-resposta" bifásica na fisiopatologia cardiovascular e pode causar efeitos deletérios, mesmo em doses não tóxicas. A VD exerce suas funções celulares ligando-se ao seu receptor. Ainda, a expressão da proteína de interação com a tiorredoxina (TXNIP) é positivamente regulada pela VD. A TXNIP modula diferentes visa de sinalização celular que podem ser importantes para a remodelação cardíaca. OBJETIVOS: Avaliar se a suplementação com VD leva à remodelação cardíaca, e se a TXNIP e a tiorredoxina (Trx) estão associadas com esse processo. MÉTODOS: Duzentos e cinquenta ratos Wistar machos foram alocados em três grupos: controle (C, n=21), sem suplementação com VD; VD3 (n = 22) e VD10 (n=21), suplementados com 3,000 e 10,000 UI de VD/ kg de ração, respectivamente, por dois meses. Os grupos foram comparados por análise de variância (ANOVA) com um fator e teste post hoc de Holm-Sidak (variáveis com distribuição normal), ou pelo teste de Kruskal-Wallis e análise post-hoc de Dunn. O nível de significância para todos os testes foi de 5%. RESULTADOS: A expressão de TXNIP foi mais alta e a atividade do Trx foi mais baixa no grupo VD10. Os animais que receberam suplementação com VD apresentaram aumento de hidroperóxido lipídico e diminuição de superóxido dismutase e glutationa peroxidase. A proteína Bcl-2 foi mais baixa no grupo VD10. Observou-se uma diminuição na ß-oxidação de ácidos graxos, no ciclo do ácido tricarboxílico, na cadeia transportadora de elétrons, e um aumento na via glicolítica. CONCLUSÃO: A suplementação com VD levou à remodelação cardíaca e esse processo pode ser modulado por TXNIP e Trx, e consequentemente por estresse oxidativo.


Assuntos
Tiorredoxinas , Remodelação Ventricular , Animais , Proteínas de Ciclo Celular , Suplementos Nutricionais , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Tiorredoxinas/metabolismo , Vitamina D
14.
PLoS One ; 16(9): e0257282, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34516590

RESUMO

Neonatal screening is essential for child health and has the following purposes: (1) pulse oximetry screening to evaluate congenital heart diseases; (2) red reflex examination to investigate eye diseases; (3) newborn hearing screening test to evaluate congenital hearing diseases; (4) tongue test to evaluate the lingual frenulum and identify communication and feeding problems; (5) the Guthrie test to screen for metabolic diseases. This study investigated the prevalence of the five neonatal screening tests and its associated institutional and socio-cultural factors using a cross-sectional study with 415 mother and baby binomials from public maternity hospitals in Natal, RN, Brazil in 2019. Pearson's chi-squared, Mann-Whitney and Poisson regression tests were used, with a significance of p ≤ 0.05 and a 95% confidence interval. The sample loss was 71 mothers (17%). The prevalence in the first week and at the end of 28 days was 93% and 99.5% (pulse oximetry screening), 60% and 97.6% (red reflex examination), 71.9% and 93.6% (Guthrie test), 35.5% and 68.2% (hearing screening test), and 19% and 48.9% (tongue test). Only 152 newborns (36.6%) underwent all five tests. The performance of the tests was associated in the final model (p ≤ 0.05) with the residence of the mothers in the state capital (PR = 1.36; 95% CI = 1.18-1.56) and the provision of guidance for mothers about the five tests in maternity hospitals (PR = 1.30; 95% CI = 1.08-1.67). None of the tests met full coverage, and regional inequities were identified indicating the need to restructure the institutions, training and qualification procedures to improve of the work processes and longitudinal care.


Assuntos
Triagem Neonatal/métodos , Brasil , Estudos Transversais , Feminino , Testes Auditivos/estatística & dados numéricos , Maternidades/estatística & dados numéricos , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Humanos , Recém-Nascido , Gravidez
15.
J Diabetes Metab Disord ; 19(1): 187-196, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32550168

RESUMO

OBJECTIVE: The objective of this study was to evaluate the effects of intake of Brazil nut extract (BN) or sodium selenite solution on reproductive parameters of male diabetic animals. METHODS: A total of 48 Wistar rats were distributed into six groups: diabetes (n = 8); diabetes and Brazil nut extract (n = 8); diabetes and sodium selenite (Na2SeO3) (n = 8); Brazil nut extract (n = 8); sodium selenite (n = 8) and control (n = 8). A single dose of streptozotocin (65 mg/kg) was injected intravenously to the rats to induce diabetes. BN or Na2SeO3 were administered by gavage for 56 days. RESULTS: The diabetes caused critical alterations on body mass gain, reproductive parameters and antioxidant capacity. Treatments with both BN or Na2SeO3 were able to increase significantly the glutathione peroxidase and the daily sperm production, both in diabetic (p < 0.01 and p < 0.05) and in healthy animals (p < 0.01 and p < 0.05). CONCLUSION: The Brazil nut extract and sodium selenite were able to improve some reproductive parameters of diabetic rats. Moreover, we could infer that this effect is probably due to the natural selenium content of the BN.

16.
Diabetes Ther ; 11(10): 2237-2255, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32654070

RESUMO

INTRODUCTION: Hypoglycemia leading to hospitalization is associated with adverse economic outcomes, although the real burden is unknown. The HIPOS-WARD (Hypoglycemia In Portugal Observational Study-Ward) aimed to characterize ward admissions due to hypoglycemia episodes in treated patients with diabetes and assess their economic impact to the National Health System. METHODS: Observational, cross-sectional study, conducted in 16 Portuguese centers for 22 months. The applied microcosting approach was based on healthcare resource data, collected from patients' charts upon ward admission until discharge, and unitary costs from official/public data sources. Absenteeism was also estimated for active workers on the basis of the human capital approach. RESULTS: Of the 176 patients with diabetes mellitus enrolled, 86% had type 2 diabetes. Half of the patients (50.0%) were on insulin-based therapy, followed by 30.1% on a secretagogue-based regimen, 9.7% on non-secretagogue therapy, and 10.2% on a combination of insulin and secretagogue. Overall mean costs per patient were medication, 45.45 €; laboratory analysis, 218.14 €; examinations, 64.91 €; physician and nurse time, 268.55 € and 673.39 €, respectively. Bed occupancy was the main cost driver (772.09 €) and indirect cost averaged 140.44 €. Overall, the cost per hypoglycemia episode leading to hospitalization averaged 2042.52 € (range 194.76-16,762.87 €). Patients treated with insulin-based regimens (2267.76 €) and type 2 diabetes (2051.29 €) had the highest mean costs. The mean cost increased with repeated hypoglycemic events (2191.67 €), correlated complications (2109.26 €), and death (5253.38 €). CONCLUSION: HIPOS-WARD's findings confirm and support both the substantial clinical and economic impact of hospitalization due to hypoglycemia in Portugal.

17.
Behav Pharmacol ; 20(2): 134-45, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19307960

RESUMO

The strain of spontaneously hypertensive rats (SHR) is considered a genetic model for the study of attention-deficit hyperactivity disorder (ADHD), as it displays hyperactivity, impulsivity and poorly sustained attention. Recently, we have shown the involvement of adenosinergic neuromodulation in the SHR's short-term and long-term memory impairments. In this study, we investigated the performance of male and female SHR in a modified version of the object-recognition task (using objects with different structural complexity) and compared them with Wistar rats, a widely used outbred rat strain for the investigation of learning processes. The suitability of the SHR strain to represent an animal model of ADHD, as far as mnemonic deficits are concerned, was pharmacologically validated by the administration of methylphenidate, the first-choice drug for the treatment of ADHD patients. The role of adenosine A1 and A2A receptors in object discrimination was investigated by the administration of caffeine (nonselective antagonist) or selective adenosine receptor antagonists. Wistar rats discriminated all the objects used (cube vs. pyramid; cube vs. T-shaped object), whereas SHR only discriminated the most structurally distinct pairs of objects (cube vs. pyramid). Pretraining administration of methylphenidate [2 mg/kg, intraperitoneal (i.p.)], caffeine (1-10 mg/kg, i.p.), the selective adenosine receptor antagonists DPCPX (8-cyclopenthyl-1,3-dipropylxanthine; A1 antagonist, 5 mg/kg, i.p.) and ZM241385 (A2A antagonist, 1.0 mg/kg, i.p.), or the association of ineffective doses of DPCPX (3 mg/kg) and ZM241385 (0.5 mg/kg), improved the performance of SHR in the object-recognition task. These findings show that the discriminative learning impairments of SHR can be attenuated by the blockade of either A1 or A2A adenosine receptors, suggesting that adenosinergic antagonists might represent potentially interesting drugs for the treatment of ADHD.


Assuntos
Antagonistas do Receptor A1 de Adenosina , Antagonistas do Receptor A2 de Adenosina , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Memória de Curto Prazo/efeitos dos fármacos , Ratos Endogâmicos SHR/fisiologia , Reconhecimento Psicológico/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Cafeína/farmacologia , Modelos Animais de Doenças , Feminino , Masculino , Memória de Curto Prazo/fisiologia , Metilfenidato/farmacologia , Ratos , Ratos Wistar , Receptor A1 de Adenosina/fisiologia , Receptores A2 de Adenosina/fisiologia , Reconhecimento Psicológico/fisiologia , Triazinas/administração & dosagem , Triazinas/farmacologia , Triazóis/administração & dosagem , Triazóis/farmacologia , Xantinas/administração & dosagem , Xantinas/farmacologia
18.
Cell Rep ; 29(9): 2890-2900.e5, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31775053

RESUMO

RNA-DNA hybrids are tightly regulated to ensure genome integrity. The RNase H enzymes RNase H1 and H2 contribute to chromosomal stability through the removal of RNA-DNA hybrids. Loss of RNase H2 function is implicated in human diseases of the nervous system and cancer. To better understand RNA-DNA hybrid dynamics, we focused on elucidating the regulation of the RNase H enzymes themselves. Using yeast as a model system, we demonstrate that RNase H1 and H2 are controlled in different manners. RNase H2 has strict cell cycle requirements, in that it has an essential function in G2/M for both R-loop processing and ribonucleotide excision repair. RNase H1, however, can function independently of the cell cycle to remove R-loops and appears to become activated in response to high R-loop loads. These results provide us with a more complete understanding of how and when RNA-DNA hybrids are acted upon by the RNase H enzymes.


Assuntos
DNA/metabolismo , RNA/metabolismo , Ribonuclease H/metabolismo , Humanos
19.
J Ethnopharmacol ; 215: 14-20, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29274355

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Vitex megapotamica (Spreng.) Moldenke is a deciduous tree, native of South America. Its leaves are traditionally used to treat cardiovascular diseases. This activity is related to the presence of flavonoids, the major compounds of the crude extract. AIM OF THE STUDY: This study investigated the effects of the oral administration of crude extract and standardized fractions from V. megapotamica leaves on lipid profile and on the formation of atherosclerotic plaque in C57BL/6 LDLr-KO mice treated with high-fat diet (HFD). MATERIALS AND METHODS: Male C57BL/6 LDLr-KO mice were fed with HFD (cholesterol, 1.25%) for 30 days. They were treated with hydroethanolic extract (500 or 1000mg/kg/day) or fractions (125 or 250mg/kg/day). After 30 days of treatment, it was evaluated the serum lipid profile, atherogenic index, and atherosclerotic plaque. RESULTS: All doses of the hydroethanolic extract reduced significantly the levels of total cholesterol, triglycerides, LDL-c and the atherogenic index. The n-butanolic fraction also reduced significantly the levels of total cholesterol, triglycerides, LDL-c and the atherogenic index, at all doses, with exception for the triglycerides, which only the lower dose was effective. The residual fraction reduced significantly the levels of total cholesterol, LDL-c and the atherogenic index, at all doses, with exception for the atherogenic index, which only the higher dose was effective. The atherosclerotic plaque formation was impaired only by the lower dose of the hydroethanolic extract. CONCLUSIONS: Overall, our data suggest that V. megapotamica has potential for the treatment of dyslipidemias.


Assuntos
Hiperlipidemias/induzido quimicamente , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/farmacologia , Extratos Vegetais/farmacologia , Vitex/química , Animais , Dieta Hiperlipídica/efeitos adversos , Hiperlipidemias/sangue , Hipolipemiantes/administração & dosagem , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fitoterapia , Extratos Vegetais/química , Lectinas de Plantas/química , Receptores de LDL/genética , Receptores de LDL/metabolismo
20.
PLoS One ; 12(7): e0181065, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28742140

RESUMO

Splice-switching antisense oligonucleotides (SSOs) offer great potential for RNA-targeting therapies, and two SSO drugs have been recently approved for treating Duchenne Muscular Dystrophy (DMD) and Spinal Muscular Atrophy (SMA). Despite promising results, new developments are still needed for more efficient chemistries and delivery systems. Locked nucleic acid (LNA) is a chemically modified nucleic acid that presents several attractive properties, such as high melting temperature when bound to RNA, potent biological activity, high stability and low toxicity in vivo. Here, we designed a series of LNA-based SSOs complementary to two sequences of the human dystrophin exon 51 that are most evolutionary conserved and evaluated their ability to induce exon skipping upon transfection into myoblasts derived from a DMD patient. We show that 16-mers with 60% of LNA modification efficiently induce exon skipping and restore synthesis of a truncated dystrophin isoform that localizes to the plasma membrane of patient-derived myotubes differentiated in culture. In sum, this study underscores the value of short LNA-modified SSOs for therapeutic applications.


Assuntos
Distrofina/biossíntese , Distrofina/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/terapia , Oligonucleotídeos Antissenso/uso terapêutico , Oligonucleotídeos/uso terapêutico , Linhagem Celular , Éxons , Terapia Genética/métodos , Humanos , Fibras Musculares Esqueléticas/metabolismo , Distrofia Muscular de Duchenne/genética , Oligonucleotídeos/genética , Oligonucleotídeos Antissenso/genética , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Splicing de RNA
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