Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Neurosci ; 16: 929590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36117620

RESUMO

Neurodegenerative disorders are a critical affection with a high incidence around the world. Currently, there are no effective treatments to solve this problem. However, the application of mesenchymal stem cells (MSCs) and antioxidants in neurodegenerative diseases has shown to be a promising tool due to their multiple therapeutic effects. This work aimed to evaluate the effects of a combination of resveratrol (RSV) and coenzyme Q10 (CoQ10) on the proliferation and differentiation of MSC and the protector effects in induced damage. To characterize the MSCs, we performed flow cytometry, protocols of cellular differentiation, and immunocytochemistry analysis. The impact of RSV + CoQ10 in proliferation was evaluated by supplementing 2.5 and 10 µM of RSV + CoQ10 in a cellular kinetic for 14 days. Cell viability and lactate dehydrogenase levels (LDH) were also analyzed. The protective effect of RSV + CoQ10 was assessed by supplementing the treatment to damaged MSCs by 1-methyl-4-phenylpyridinium (MPP+); cellular viability, LDH, and reactive oxygen species (ROS) were evaluated.. MSCs expressed the surface markers CD44, CD73, CD90, and CD105 and showed multipotential ability. The combination of RSV + CoQ10 increased the proliferation potential and cell viability and decreased LDH levels. In addition, it reverted the effect of MPP+-induced damage in MSCs to enhance cell viability and decrease LDH and ROS. Finally, RSV + CoQ10 promoted the differentiation of neural progenitors. The combination of RSV + CoQ10 represents a potential treatment to improve MSCs capacities and protect against neurodegenerative damage.

2.
Front Cell Dev Biol ; 9: 676998, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249929

RESUMO

There have been significant advances in understanding human embryogenesis using human pluripotent stem cells (hPSCs) in conventional monolayer and 3D self-organized cultures. Thus, in vitro models have contributed to elucidate the molecular mechanisms for specification and differentiation during development. However, the molecular and functional spectrum of human pluripotency (i.e., intermediate states, pluripotency subtypes and regionalization) is still not fully understood. This review describes the mechanisms that establish and maintain pluripotency in human embryos and their differences with mouse embryos. Further, it describes a new pluripotent state representing a transition between naïve and primed pluripotency. This review also presents the data that divide pluripotency into substates expressing epiblast regionalization and amnion specification as well as primordial germ cells in primates. Finally, this work analyzes the amnion's relevance as an "signaling center" for regionalization before the onset of gastrulation.

3.
Mol Cell Biochem ; 476(7): 2703-2718, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33666829

RESUMO

The zinc transporter 8 (ZnT8) plays an essential role in zinc homeostasis inside pancreatic ß cells, its function is related to the stabilization of insulin hexameric form. Genome-wide association studies (GWAS) have established a positive and negative relationship of ZnT8 variants with type 2 diabetes mellitus (T2DM), exposing a dual and controversial role. The first hypotheses about its role in T2DM indicated a higher risk of developing T2DM for loss of function; nevertheless, recent GWAS of ZnT8 loss-of-function mutations in humans have shown protection against T2DM. With regard to the ZnT8 role in T2DM, most studies have focused on rodent models and common high-risk variants; however, considerable differences between human and rodent models have been found and the new approaches have included lower-frequency variants as a tool to clarify gene functions, allowing a better understanding of the disease and offering possible therapeutic targets. Therefore, this review will discuss the physiological effects of the ZnT8 variants associated with a major and lower risk of T2DM, emphasizing the low- and rare-frequency variants.


Assuntos
Diabetes Mellitus Tipo 2 , Transportador 8 de Zinco , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Transportador 8 de Zinco/deficiência , Transportador 8 de Zinco/metabolismo
4.
J Vis Exp ; (153)2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31840672

RESUMO

Several protocols have been reported in the literature for the isolation and culture of human amniotic epithelial cells (HAEC). However, these assume that the amniotic epithelium is a homogeneous layer. The human amnion can be divided into three anatomical regions: reflected, placental, and umbilical. Each region has different physiological roles, such as in pathological conditions. Here, we describe a protocol to dissect human amnion tissue in three sections and maintain it in vitro. In culture, cells derived from the reflected amnion displayed a cuboidal morphology, while cells from both placental and umbilical regions were squamous. Nonetheless, all the cells obtained have an epithelial phenotype, demonstrated by the immunodetection of E-cadherin. Thus, because the placental and reflected regions in situ differ in cellular components and molecular functions, it may be necessary for in vitro studies to consider these differences, because they could have physiological implications for the use of HAEC in biomedical research and the promising application of these cells in regenerative medicine.


Assuntos
Âmnio/citologia , Biomarcadores/metabolismo , Células Epiteliais/citologia , Placenta/citologia , Âmnio/metabolismo , Antígenos CD/metabolismo , Caderinas/metabolismo , Células Cultivadas , Células Epiteliais/metabolismo , Feminino , Humanos , Placenta/metabolismo , Gravidez
5.
Plant Foods Hum Nutr ; 73(1): 34-39, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29417384

RESUMO

Obesity affects millions of people worldwide, constituting a public health problem associated with premature mortality. Agave fructans decrease fat mass, body and liver weight, and generate satiety in rodents. In the present study the effects of agave fructans on weight control, lipid profile, and physical tolerability were evaluated in obese people. Twenty-eight obese volunteers were randomly divided into two groups. In the first group, 96 mg/bw of agave fructans was administered for 12 weeks; in the second group, maltodextrin as a placebo was administered for 12 weeks. All participants consumed a low-calorie diet of 1500 kcal/day. Anthropometric and biochemical measurements were taken at baseline and at the end of the study. The body mass index (BMI) of the agave fructans treated group was reduced significantly from the baseline to the final measurements. Hip and waist circumferences decreased statistically in both groups. A decrease of 10% in total body fat was observed in the agave fructans treated group, resulting in a statistically significant difference in the final versus baseline measurements between the Agave fructans treated group and the placebo treated group. Triglycerides were reduced significantly in the agave fructans treated group. Glucose values did not change in either group. Agave fructans intake was safe and well tolerated throughout the study. The results showed that the ingestion of agave fructans enhanced the decrease in BMI, the decrease in total body fat, and the decrease in triglycerides in obese individuals who consume a low-calorie diet.


Assuntos
Agave/química , Fármacos Antiobesidade/farmacologia , Frutanos/farmacologia , Lipídeos/sangue , Obesidade/tratamento farmacológico , Tecido Adiposo/efeitos dos fármacos , Adolescente , Adulto , Índice de Massa Corporal , Restrição Calórica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Triglicerídeos/sangue
6.
Int J Dev Neurosci ; 27(5): 493-500, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19379802

RESUMO

Estradiol protects dopamine neurons of the substantia nigra from toxic insults. Such neurons succumb in Parkinson's disease; one strategy for restoring dopamine deficiency is cell therapy with neurons differentiated from embryonic stem cells. We investigated the effects of 17beta-estradiol on dopaminergic induction of embryonic stem cells using the 5-stage protocol. Cells were incubated with different steroid concentrations during the proliferation (stage 4) or differentiation (stage 5) phases. Estradiol added at nM concentrations only during stage 4 increases the proliferation of dopaminergic precursors expressing Lmx1a, inducing a higher proportion of dopamine neurons at stage 5. These actions were mediated by activation of estrogen receptors, because co-incubation of cells with estradiol and ICI 182,780 completely abolished the positive effect on both proliferation of committed precursors, and subsequent differentiation to dopaminergic neurons. Our results suggest that estradiol should be useful in producing higher proportions of dopamine neurons from embryonic stem cells aimed for treating Parkinson's disease.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estradiol/farmacologia , Proteínas de Homeodomínio/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Animais , Western Blotting , Proteína C-Reativa/metabolismo , Contagem de Células , Células Cultivadas , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Células-Tronco Embrionárias/citologia , Imuno-Histoquímica , Proteínas com Homeodomínio LIM , Masculino , Camundongos , Microscopia Confocal , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição
7.
Brain Res Bull ; 73(1-3): 75-80, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17499639

RESUMO

Embryonic stem cells (ESC) can differentiate to derivatives of the three embryonic germ layers. Dopamine neurons have been produced from mouse and human ESC. This in vitro induction mimics the developmental program followed by dopaminergic cells in vivo. Production of dopamine neurons might have clinical applications for Parkinson's disease, which has a higher incidence in men than in women, suggesting a protective role for sex hormones, particularly progesterone and estradiol. These hormones exert many of their effects through the interaction with their nuclear receptors. In this study, we used a described 5-stage protocol for dopamine neuron differentiation of ESC, allowing neuronal commitment as evidenced by specific markers and by behavioural recovery of hemiparkinsonian rats after grafting. We studied the expression of steroid hormone receptors by immunoblot during this procedure and found an increase in the content of both A and B isoforms of progesterone receptor (PR) and a decrease in estrogen receptor alpha (ER-alpha) when cells were at the neural/neuronal stages, when compared with the amount found in initial pluripotent conditions. We also found the same pattern of PR and ER-alpha expression by immunocytochemistry. Ninety-two percent of dopamine neurons expressed progesterone receptors and only 19% of these neurons co-expressed tyrosine hydroxylase and ER-alpha. These results show a differential expression pattern of ER-alpha and PR isoforms during neuronal differentiation of ESC.


Assuntos
Diferenciação Celular/fisiologia , Dopamina/fisiologia , Células-Tronco Embrionárias/fisiologia , Receptor alfa de Estrogênio/metabolismo , Neurônios/fisiologia , Receptores de Progesterona/metabolismo , Animais , Western Blotting , Densitometria , Eletroforese em Gel de Poliacrilamida , Feminino , Imuno-Histoquímica , Camundongos , Microscopia Confocal , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Fator 3 de Transcrição de Octâmero/biossíntese , Oxidopamina , Gravidez , Transplante de Células-Tronco , Tirosina 3-Mono-Oxigenase/biossíntese
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...