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1.
Br J Nutr ; 124(11): 1179-1189, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-32594915

RESUMO

Whole-grain wheat, in particular coloured varieties, may have health benefits in adults with chronic metabolic disease risk factors. Twenty-nine overweight and obese adults with chronic inflammation (high-sensitivity C-reactive protein) > 1·0 mg/l) replaced four daily servings of refined grain food products with bran-enriched purple or regular whole-wheat convenience bars (approximately 41-45 g fibre, daily) for 8 weeks in a randomised, single-blind parallel-arm study where body weight was maintained. Anthropometrics, blood markers of inflammation, oxidative stress, and lipaemia and metabolites of anthocyanins and phenolic acids were compared at days 1, 29 and 57 using repeated-measures ANOVA within groups and ANCOVA between groups at day 57, with day 1 as a covariate. A significant reduction in IL-6 and increase in adiponectin were observed within the purple wheat (PW) group. TNF-α was lowered in both groups and ferulic acid concentration increased in the regular wheat (RW) group. Comparing between wheats, only plasma TNF-α and glucose differed significantly (P < 0·05), that is, TNF-α and glucose decreased with RW and PW, respectively. Consumption of PW or RW products showed potential to improve plasma markers of inflammation and oxidative stress in participants with evidence of chronic inflammation, with modest differences observed based on type of wheat.


Assuntos
Proteína C-Reativa/metabolismo , Ingestão de Alimentos/fisiologia , Obesidade/sangue , Sobrepeso/sangue , Triticum , Grãos Integrais , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Fatores de Risco Cardiometabólico , Dieta/métodos , Feminino , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Método Simples-Cego , Adulto Jovem
2.
Prostate ; 75(7): 693-705, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25650269

RESUMO

BACKGROUND: New therapies are required for castrate-resistant prostate cancer (CRPC), and growth-arrest specific 5 (GAS5) lncRNA, which riborepresses androgen receptor action, may offer novel opportunities in this regard. This lncRNA promotes the apoptosis of prostate cancer cells and its levels decline as prostate cancer cells acquire castrate-resistance, so that enhancing GAS5 expression may improve the effectiveness of chemotherapies. Since GAS5 is a member of the 5' terminal oligopyrimidine gene family, we have examined mTOR inhibition as a strategy to increase GAS5 expression. Furthermore, we have determined if GAS5 itself mediates the action of mTOR inhibitors, as demonstrated for other chemotherapeutic agents in prostate cancer cells. METHODS: The effects of mTOR inhibitors on GAS5 lncRNA levels and cell growth were determined in a range of prostate cancer cell lines. Transfection of cells with GAS5 siRNAs and plasmid constructs was performed to determine the involvement of GAS5 lncRNA in mTOR inhibitor action. RESULTS: First generation mTORC1, combined mTORC1/mTORC2 and dual PI3K/mTOR inhibitors all increased cellular GAS5 levels and inhibited culture growth in androgen-dependent (LNCaP) and androgen-sensitive (22Rv1) cell lines, but not in androgen-independent (PC-3 and DU 145) cell lines. The latter exhibited low endogenous GAS5 expression, and GAS5 silencing in LNCaP and 22Rv1 cells decreased the sensitivity to mTOR inhibitors, whereas transfection of GAS5 lncRNA sensitized PC-3 and DU 145 cells to these agents. CONCLUSION: mTOR inhibition enhances GAS5 transcript levels in certain prostate cancer cell lines. This selectivity is likely to be related to endogenous GAS5 expression levels, since GAS5 lncRNA is itself required for mTOR inhibitor action in prostate cancer cells.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias da Próstata/metabolismo , RNA Longo não Codificante/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , RNA Longo não Codificante/genética , RNA Neoplásico/química , RNA Neoplásico/genética , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
3.
Breast Cancer Res Treat ; 145(2): 359-70, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24789445

RESUMO

The putative tumour suppressor and apoptosis-promoting gene, growth arrest-specific 5 (GAS5), encodes long ncRNA (lncRNA) and snoRNAs. Its expression is down-regulated in breast cancer, which adversely impacts patient prognosis. In this preclinical study, the consequences of decreased GAS5 expression for breast cancer cell survival following treatment with chemotherapeutic agents are addressed. In addition, functional responses of triple-negative breast cancer cells to GAS5 lncRNA are examined, and mTOR inhibition as a strategy to enhance cellular GAS5 levels is investigated. Breast cancer cell lines were transfected with either siRNA to GAS5 or with a plasmid encoding GAS5 lncRNA and the effects on breast cancer cell survival were determined. Cellular responses to mTOR inhibitors were evaluated by assaying culture growth and GAS5 transcript levels. GAS5 silencing attenuated cell responses to apoptotic stimuli, including classical chemotherapeutic agents; the extent of cell death was directly proportional to cellular GAS5 levels. Imatinib action in contrast, was independent of GAS5. GAS5 lncRNA promoted the apoptosis of triple-negative and oestrogen receptor-positive cells but only dual PI3K/mTOR inhibition was able to enhance GAS5 levels in all cell types. Reduced GAS5 expression attenuates apoptosis induction by classical chemotherapeutic agents in breast cancer cells, providing an explanation for the relationship between GAS5 expression and breast cancer patient prognosis. Clinically, this relationship may be circumvented by the use of GAS5-independent drugs such as imatinib, or by restoration of GAS5 expression. The latter may be achieved by the use of a dual PI3K/mTOR inhibitor, to improve apoptotic responses to conventional chemotherapies.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , RNA Longo não Codificante , Apoptose/genética , Benzamidas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Células MCF-7/patologia , Morfolinas/farmacologia , Piperazinas/farmacologia , Pirimidinas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
4.
Nanomedicine ; 10(2): 291-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24090767

RESUMO

Non-neuronal cells of the central nervous system (CNS), termed "neuroglia," play critical roles in neural regeneration; therefore, replacement of glial populations via implantable nanofabricated devices (providing a growth-permissive niche) is a promising strategy to enhance repair. Most constructs developed to date have lacked three-dimensionality, multiple glial populations and control over spatial orientations, limiting their ability to mimic in vivo neurocytoarchitecture. We describe a facile technique to incorporate multiple glial cell populations [astrocytes, oligodendrocyte precursor cells (OPCs) and oligodendrocytes] within a three-dimensional (3D) nanofabricated construct. Highly aligned nanofibers could induce elongation of astrocytes, while OPC survival, elongation and maturation required pre-aligned astrocytes. The potential to scale-up the numbers of constituent nanofiber layers is demonstrated with astrocytes. Such complex implantable constructs with multiple glial sub-populations in defined 3D orientations could represent an effective approach to reconstruct glial circuitry in neural injury sites. FROM THE CLINICAL EDITOR: Clinically available methods to enhance nervous tissue regeneration remain scarce despite decades of research. In this study, a novel 3D nanofabricated construct is demonstrated, that includes populations of astrocytes, oligodendrocyte precursor cells and oligodendrocytes providing a well-orchestrated glial microenvironment for more efficient central nervous system repair.


Assuntos
Nanofibras/química , Regeneração Nervosa , Neuroglia/citologia , Neurônios/metabolismo , Alicerces Teciduais , Animais , Animais Recém-Nascidos , Astrócitos/citologia , Células Cultivadas , Sistema Nervoso Central/metabolismo , Técnicas de Cocultura , Hidrogéis/química , Bainha de Mielina/fisiologia , Neurônios/patologia , Oligodendroglia/citologia , Ratos , Ratos Sprague-Dawley , Células-Tronco/fisiologia
5.
Nanomedicine ; 9(6): 737-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23751375

RESUMO

Safe genetic modification of neural stem cell (NSC) transplant populations is a key goal for regenerative neurology. We describe a technically simple and safe method to increase transfection in NSCs propagated in the neurosphere (suspension culture) model, using magnetic nanoparticles deployed with applied oscillating magnetic fields ('magnetofection technology'). We show that transfection efficiency was enhanced over two-fold by oscillating magnetic fields (frequency=4 Hz). The protocols had no effect on cell viability, cell number, stem cell marker expression and differentiation profiles of 'magnetofected' cultures, highlighting the safety of the technique. As far as we are aware, this is the first successful application of magnetofection technology to suspension cultures of neural cells. The procedures described offer a means to augment the therapeutic potential of NSCs propagated as neurospheres - a culture model of high clinical translational relevance - by safe genetic manipulation, with further potential for incorporation into 'magneto-multifection' (repeat transfection) protocols. FROM THE CLINICAL EDITOR: This team of investigators describe a simple and safe method to increase transfection in neural stem cells using magnetic nanoparticles deployed with oscillating magnetic fields, demonstrating a greater than two-fold transfection efficiency increase by applying low frequency magnetic oscillation.


Assuntos
Técnicas de Cultura de Células/métodos , Nanopartículas de Magnetita/química , Células-Tronco Neurais/citologia , Transfecção , Animais , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , Humanos , Campos Magnéticos , Nanopartículas de Magnetita/administração & dosagem , Células-Tronco Neurais/química
6.
Biochim Biophys Acta ; 1812(9): 1146-53, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21550398

RESUMO

FAU, which encodes a ubiquitin-like protein (termed FUBI) with ribosomal protein S30 as a carboxy-terminal extension, has recently been identified as a pro-apoptotic regulatory gene. This activity may be mediated by Bcl-G (a pro-apoptotic member of the Bcl-2 family) which can be covalently modified by FUBI. FAU gene expression has been shown to be down-regulated in human breast, prostate and ovarian tumours, and this down-regulation is strongly associated with poor prognosis in breast cancer. We demonstrate here that ectopic FAU expression increases basal apoptosis in human T-cell lines and 293T/17 cells, whereas it has only a transient stimulatory effect on ultraviolet-C (UVC)-induced apoptosis. Conversely, siRNA-mediated silencing of FAU gene expression has no effect on basal apoptosis, but attenuates UV-induced apoptosis. Importantly, prior knockdown of Bcl-G expression ablates the stimulation of basal apoptosis by FAU, consistent with an essential downstream role for Bcl-G, itself a candidate tumour suppressor, in mediating the apoptosis regulatory role of FAU. In 293T/17 cells, Bcl-G knockdown also attenuates UV-induced apoptosis, so that Bcl-G may constitute a common factor in the pathways by which both FAU and UV-irradiation induce apoptosis. UV irradiation increases Bcl-G mRNA levels, providing an explanation for the transient nature of the effect of ectopic FAU expression on UV-induced apoptosis. Since failure of apoptosis is fundamental to the development of many cancers, the pro-apoptotic activity of the Fau/Bcl-G pathway offers an attractive explanation for the putative tumour suppressor role of FAU.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Ribossômicas/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Técnicas de Silenciamento de Genes , Inativação Gênica , Células HEK293 , Humanos , Células Jurkat , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/efeitos da radiação , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/efeitos da radiação , Raios Ultravioleta
7.
Pharm Res ; 29(5): 1328-43, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22134779

RESUMO

PURPOSE: To develop Fe(3)O(4)-PEI-RITC magnetic nanoparticles with multimodal MRI-fluorescence imaging and transfection capability, for use in neural cell replacement therapies. METHODS: The Fe(3)O(4)-PEI-RITC MNPs were synthesised through a multi-step chemical grafting procedure: (i) Silanisation of MNPs with 3-iodopropyltrimethoxysilane; (ii) PEI coupling with iodopropyl groups on the MNP surface; and (iii) RITC binding onto the PEI coating. The cell labelling and transfection capabilities of these particles were evaluated in astrocytes derived from primary cultures. RESULTS: Fe(3)O(4)-PEI-RITC MNPs did not exert acute toxic effects in astrocytes (at ≤ 6 days). Cells showed rapid and extensive particle uptake with up to 100% cellular labelling observed by 24 h. MRI and microscopy studies demonstrate that the particles have potential for use in bimodal MR-fluorescence imaging. Additionally, the particles were capable of delivering plasmids encoding reporter protein (approximately 4 kb) to astrocytes, albeit with low efficiencies. CONCLUSIONS: Multifunctional Fe(3)O(4)-PEI-RITC MNPs were successfully prepared using a multi-step synthetic pathway, with the PEI and RITC chemically bound onto the MNP surface. Their combined MR-fluorescence imaging capabilities with additional potential for transfection applications can provide a powerful tool, after further development, for non-invasive cell tracking and gene transfer to neural transplant populations.


Assuntos
Transplante de Células , Compostos Férricos/química , Técnicas de Transferência de Genes , Iminas/química , Magnetismo , Nanopartículas , Polietilenos/química , Animais , Astrócitos/metabolismo , Astrócitos/transplante , Células Cultivadas , Imuno-Histoquímica , Microscopia de Fluorescência , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
8.
Food Chem ; 396: 133649, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35842998

RESUMO

The present study aimed to tackle research gaps regarding how infrared heating affected macro- and micronutrients of lentil flours from seeds varying in size. Infrared treatments reduced resistant starch contents of lentil flours from 26.1-33.6% to 6.0-17.8%, increased protein digestibility from 73.6-75.0% to 78.2-82.2%, and enhanced soluble dietary fiber contents from 6.1-7.8% to 7.4-10.3%. Infrared treatments did not alter the primary limiting amino acid of Greenstar and Imvincible lentil flours (tryptophan) but changed that of Maxim to methionine + cysteine at 150 °C heating. Regarding micronutrients, the thermal modifications decreased the levels of heat-labile B vitamins, including B1 (thiamine), B3 (niacin), and B9 (mainly 5-methylterahydrofolate), consistent with reducing α-amylase activity to an undetectable level in all the three lentil flours. The novel findings from this research will be meaningful for the agri-food industry to utilize infrared processing as an effective and clean-label approach to improving the nutritional profiles of lentil and other flours.


Assuntos
Lens (Planta) , Farinha/análise , Calefação , Lens (Planta)/química , Micronutrientes/análise , Valor Nutritivo , Sementes/química , Amido/metabolismo
9.
Genes Chromosomes Cancer ; 49(1): 70-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19830698

RESUMO

The development of chemotherapy resistance by cancer cells is complex, using different mechanisms and pathways. The gene FAU (Finkel-Biskis-Reilly murine sarcoma virus (FBR-MuSV)-associated ubiquitously expressed gene) was identified through functional expression cloning and previous data have shown that overexpression enhances apoptosis in several cell types. We demonstrate that the expression of FAU was reduced in the A2780cis (cisplatin resistant subclone of A2780) cell line compared with the A2780 ovarian cancer cell line, and was directly related to the cell line's sensitivity to carboplatin. Downregulation of FAU in the A2780 cell line by transfection with two predesigned short-interfering RNAs (siRNAs) to FAU resulted in a significant increase in resistance to carboplatin-induced cell death. Downregulation resulted in increased cell viability and reduced apoptosis after 72 hr of drug treatment compared with the negative controls (Kruskal-Wallis P = 0.0002). Transfection of the A2780cis cell line with the pcDNA3 plasmid containing FAU was associated with increased sensitivity to carboplatin-induced apoptosis, with decreased cell viability and increased apoptosis (Mann Whitney P < 0.0001). The expression of FAU was examined by quantitative real-time reverse transcriptase polymerase chain reaction in normal and malignant ovarian tissue. A significant reduction in the expression of FAU was seen in the malignant compared with normal ovarian samples (Kruskal-Wallis P = 0.0261). These data support a role for FAU in the regulation of platinum-resistance in ovarian cancer. Further research is needed into the apoptotic pathway containing FAU to investigate the potential for targeted therapies to increase or restore the platinum sensitivity of ovarian cancer.


Assuntos
Carboplatina/farmacocinética , Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas/tratamento farmacológico , Proteínas Ribossômicas/fisiologia , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Neoplasias Ovarianas/patologia , RNA Interferente Pequeno/farmacologia , Proteínas Ribossômicas/genética
10.
Biology (Basel) ; 10(3)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809684

RESUMO

Animal models have been used in preclinical research to examine potential new treatments for spinal cord injury (SCI), including mesenchymal stem cell (MSC) transplantation. MSC transplants have been studied in early human trials. Whether the animal models represent the human studies is unclear. This systematic review and meta-analysis has examined the effects of MSC transplants in human and animal studies. Following searches of PubMed, Clinical Trials and the Cochrane Library, published papers were screened, and data were extracted and analysed. MSC transplantation was associated with significantly improved motor and sensory function in humans, and significantly increased locomotor function in animals. However, there are discrepancies between the studies of human participants and animal models, including timing of MSC transplant post-injury and source of MSCs. Additionally, difficulty in the comparison of functional outcome measures across species limits the predictive nature of the animal research. These findings have been summarised, and recommendations for further research are discussed to better enable the translation of animal models to MSC-based human clinical therapy.

11.
Prostate ; 70(14): 1513-23, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20687224

RESUMO

BACKGROUND: The molecular control of cell death through apoptosis is compromised in prostate cancer cells, resulting in inappropriate cell survival and resistance to cytotoxic therapy. Reduced expression of the functionally connected apoptosis-regulators and candidate tumor suppressors Fau and Bcl-G has recently been implicated in oncogenesis in other tissues. The present study examines the hypothesis that reduced expression of these genes may be involved in prostate cancer. METHODS: Fau and Bcl-G mRNA levels were determined by real time RT-PCR in two independent prostate tissue collections. In experiments in vitro, Fau and Bcl-G levels in prostate cancer cell lines were reduced using RNA interference and the effects on sensitivity to UVC irradiation were determined. RESULTS: Fau and Bcl-G mRNA levels were both lower in prostate cancer tissue than in normal prostate and Benign Prostate Hyperplasia. Active down-regulation of Fau and Bcl-G expression in vitro resulted in decreased sensitivity to UVC-induced cytotoxicity. Simultaneous down-regulation of Fau and Bcl-G produced a decrease in sensitivity which was similar to either gene alone. CONCLUSIONS: Fau and Bcl-G mRNA levels are both decreased in prostate cancer. In prostate cancer cell lines in vitro such down-regulation results in reduced sensitivity to UVC-induced cytotoxicity, consistent with the putative roles of these genes as candidate prostate tumor suppressors. The absence of an additive effect when Fau and Bcl-G were down-regulated simultaneously is consistent with the two genes acting in the same apoptosis pathway, for example, with the pro-apoptotic effects of Fau being mediated through modulation of Bcl-G.


Assuntos
Neoplasias da Próstata/genética , Proteínas Ribossômicas/genética , Idoso , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Regulação Neoplásica da Expressão Gênica , Genes bcl-1 , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Próstata/fisiologia , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Raios Ultravioleta
12.
Int J Mol Sci ; 11(3): 967-981, 2010 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-20479995

RESUMO

Magnetic nanoparticles (MNPs) are important contrast agents used to monitor a range of neuropathological processes; microglial cells significantly contribute to MNP uptake in sites of pathology. Microglial activation occurs following most CNS pathologies but it is not known if such activation alters MNP uptake, intracellular processing and toxicity. We assessed these parameters in microglial cultures with and without experimental 'activation'. Microglia showed rapid and extensive MNP uptake under basal conditions with no changes found following activation; significant microglial toxicity was observed at higher particle concentrations. Based on our findings, we suggest that avid MNP uptake by endogenous CNS microglia could significantly limit uptake by other cellular subtypes in mixed neural cell populations.


Assuntos
Nanopartículas de Magnetita , Microglia/metabolismo , Neurônios/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Córtex Cerebral/citologia , Ratos
13.
Food Res Int ; 136: 109568, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32846607

RESUMO

Lentils are an important member of the nutritious Leguminous crops, and the functional properties of lentil flours can be effectively improved by infrared heating, an efficient and short-time thermal processing method. This research primarily focused on the effects of tempering time (24-96 h) and seed size on the modification of lentils using infrared heating. Lentil seeds of three varieties, including CDC Greenstar (large green), CDC Imvincible (small green), and CDC Maxim (small red), were tempered at 25% moisture for 24, 48 and 96 h and then infrared heated to a surface temperature of 130 and 150 °C. Overall, under the same infrared heating treatment, a longer tempering period and a smaller seed size led to greater degrees of starch gelatinization and protein denaturation. In addition, a smaller seed size and a higher surface temperature tended to cause a higher level of photodegradation of amylose (possibly amylopectin too). Due to these physicochemical changes, the combined treatment of tempering and infrared heating noticeably reduced the average particle sizes, enhanced the water-holding capacity, diminished the peak and final viscosities, and decreased the gel hardness of the processed lentil flours. Generally, more obvious effects were found with higher levels of starch gelatinization, protein denaturation, and breakdown of amylose. The present study advanced our understanding of how extended tempering and seed size influenced the techno-functional properties of lentil flours modified using infrared heating. The new findings from the research are meaningful for the utilization of infrared heating to process lentil seeds for the development of novel food ingredients.


Assuntos
Farinha , Lens (Planta) , Amilose , Farinha/análise , Calefação , Sementes
14.
PLoS One ; 15(9): e0233477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925933

RESUMO

Emerging evidence indicates that a strong relationship exists between brain regenerative therapies and nutrition. Early life nutrition plays an important role during embryonic brain development, and there are clear consequences to an imbalance in nutritional factors on both the production and survival of mature neuronal populations and the infant's risk of diseases in later life. Our research and that of others suggest that vitamins play a fundamental role in the formation of neurons and their survival. There is a growing body of evidence that nicotinamide, the water-soluble amide form of vitamin B3, is implicated in the conversion of pluripotent stem cells to clinically relevant cells for regenerative therapies. This study investigated the ability of nicotinamide to promote the development of mature catecholaminergic neuronal populations (associated with Parkinson's disease) from mouse embryonic stem cells, as well as investigating the underlying mechanisms of nicotinamide's action. Nicotinamide selectively enhanced the production of tyrosine hydroxylase-expressing neurons and serotonergic neurons from mouse embryonic stem cell cultures (Sox1GFP knock-in 46C cell line). A 5-Ethynyl-2´-deoxyuridine (EdU) assay ascertained that nicotinamide, when added in the initial phase, reduced cell proliferation. Nicotinamide drove tyrosine hydroxylase-expressing neuron differentiation as effectively as an established cocktail of signalling factors, reducing the proliferation of neural progenitors and accelerating neuronal maturation, neurite outgrowth and neurotransmitter expression. These novel findings show that nicotinamide enhanced and enriched catecholaminergic differentiation and inhibited cell proliferation by directing cell cycle arrest in mouse embryonic stem cell cultures, thus driving a critical neural proliferation-to-differentiation switch from neural progenitors to neurons. Further research into the role of vitamin metabolites in embryogenesis will significantly advance cell-based regenerative medicine, and help realize their role as crucial developmental signalling molecules in brain development.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Neurais/citologia , Neurogênese/efeitos dos fármacos , Niacinamida/farmacologia , Animais , Células Cultivadas , Camundongos , Neurônios/citologia
15.
Breast Cancer Res ; 11(4): R60, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19671159

RESUMO

INTRODUCTION: Programmed cell death through apoptosis plays an essential role in the hormone-regulated physiological turnover of mammary tissue. Failure of this active gene-dependent process is central both to the development of breast cancer and to the appearance of the therapy-resistant cancer cells that produce clinical relapse. Functional expression cloning in two independent laboratories has identified Finkel-Biskis-Reilly murine sarcoma virus-associated ubiquitously expressed gene (Fau) as a novel apoptosis regulator and candidate tumour suppressor. Fau modifies apoptosis-controller Bcl-G, which is also a key target for candidate oncoprotein maternal embryonic leucine zipper kinase (MELK). METHODS: We have used RNA interference to downregulate Fau and Bcl-G expression, both simultaneously and independently, in breast cancer cells in vitro to determine the importance of their roles in apoptosis. Expression of Fau, Bcl-G and MELK was measured by quantitative RT-PCR in breast cancer tissue and in matched breast epithelial tissue from the same patients. Expression data of these genes obtained using microarrays from a separate group of patients were related to patient survival in Kaplan-Meier analyses. RESULTS: siRNA-mediated downregulation of either Fau or Bcl-G expression inhibited apoptosis, and the inhibition produced by combining the two siRNAs was consistent with control of Bcl-G by Fau. Fau expression is significantly reduced in breast cancer tissue and this reduction is associated with poor patient survival, as predicted for a candidate breast cancer tumour suppressor. In addition, MELK expression is increased in breast cancer tissue and this increase is also associated with poor patient survival, as predicted for a candidate oncogene. Bcl-G expression is reduced in breast cancer tissue but decreased Bcl-G expression showed no correlation with survival, indicating that the most important factors controlling Bcl-G activity are post-translational modification (by Fau and MELK) rather than the rate of transcription of Bcl-G itself. CONCLUSIONS: The combination of in vitro functional studies with the analysis of gene expression in clinical breast cancer samples indicates that three functionally interconnected genes, Fau, Bcl-G and MELK, are crucially important in breast cancer and identifies them as attractive targets for improvements in breast cancer risk prediction, prognosis and therapy.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Ribossômicas/fisiologia , Adenocarcinoma/mortalidade , Apoptose/genética , Apoptose/efeitos da radiação , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/efeitos da radiação , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Estudos de Associação Genética , Humanos , Estimativa de Kaplan-Meier , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Prognóstico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Ensaio Tumoral de Célula-Tronco , Raios Ultravioleta
16.
J Agric Food Chem ; 55(22): 8958-66, 2007 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-17907771

RESUMO

Moderate consumption of beer is known to be beneficial for health. Thus, antioxidant, likely taste, and aroma properties of antho-beers made from purple wheat grain (antho-grain) were evaluated. The 2,2-diphenyl-1-picryhydrazyl free radical (DPPH*) scavenging activity, total phenolic content (TPC), oxygen radical absorbance capacity (ORAC), and phenolic acid compositions of antho-bran were also investigated. DPPH* scavenging activity at 60 min was 50.6-59.9% for control and antho-beer extracts, 15.0-54.1% for antho-bran extracts and hydrolysates. The TPC ranged from 410 to 609 mg/L, from 84 to 95 mg/L, and from 2473 to 7634 mg/kg for control (from barley malt) and antho-beer original samples, control and antho-beer extracts, and antho-bran extracts and hydrolysates, respectively. The corresponding ORAC values were 3050-4181 mg/L, 2961-3184 mg/L, and 74-213 g/kg, respectively. The major known phenolic acids comprised four types in control beer, five types in antho-beers, and seven types in antho-bran hydrolysates. Total anthocyanin content of antho-bran was up to 1160 mg/kg. Differences in likely taste and aroma were found between control and antho-beers by using electronic tongue and nose methods. Brewing materials had an effect on the antioxidant, likely taste, and aroma properties of beers; however, antho-grain may have potential as a novel brewing material.


Assuntos
Antioxidantes/análise , Cerveja/análise , Odorantes/análise , Paladar , Triticum/química , Antocianinas/análise , Antioxidantes/farmacologia , Compostos de Bifenilo , Hidroxibenzoatos/análise , Fenóis/análise , Picratos , Espécies Reativas de Oxigênio/química , Sementes/química
17.
Curr Protoc Stem Cell Biol ; 40: 2D.19.1-2D.19.16, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28152180

RESUMO

Neural stem cells (NSCs) have high translational potential in transplantation therapies for neural repair. Enhancement of their therapeutic capacity by genetic engineering is an important goal for regenerative neurology. Magnetic nanoparticles (MNPs) are major non-viral vectors for safe bioengineering of NSCs, offering critical translational benefits over viral vectors, including safety, scalability, and ease of use. This unit describes protocols for the production of suspension (neurosphere) and adherent (monolayer) murine NSC cultures. Genetic engineering of NSCs with MNPs and the application of 'magnetofection' (magnetic fields) or 'multifection' (repeat transfection) approaches to enhance gene delivery are described. Magnetofection of monolayer cultures achieves optimal transfection, but neurospheres offer key advantages for neural graft survival post-transplantation. A protocol is presented which allows the advantageous features of each approach to be combined into a single procedure for transplantation. The adaptation of these protocols for other MNP preparations is considered, with emphasis on the evaluation of procedural safety. © 2017 by John Wiley & Sons, Inc.


Assuntos
Técnicas de Cultura de Células/métodos , Nanopartículas de Magnetita/química , Células-Tronco Neurais/citologia , Transfecção/métodos , Animais , Células Cultivadas , Humanos , Laminina/farmacologia , Camundongos , Peptídeos/farmacologia , Esferoides Celulares/citologia
18.
PLoS One ; 12(8): e0183358, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28817722

RESUMO

INTRODUCTION: Vitamin B3 has been shown to play an important role during embryogenesis. Specifically, there is growing evidence that nicotinamide, the biologically active form of vitamin B3, plays a critical role as a morphogen in the differentiation of stem cells to mature cell phenotypes, including those of the central nervous system (CNS). Detailed knowledge of the action of small molecules during neuronal differentiation is not only critical for uncovering mechanisms underlying lineage-specification, but also to establish more effective differentiation protocols to obtain clinically relevant cells for regenerative therapies for neurodegenerative conditions such as Huntington's disease (HD). Thus, this study aimed to investigate the potential of nicotinamide to promote the conversion of stem cells to mature CNS neurons. METHODS: Nicotinamide was applied to differentiating mouse embryonic stem cells (mESC; Sox1GFP knock-in 46C cell line) during their conversion towards a neural fate. Cells were assessed for changes in their proliferation, differentiation and maturation; using immunocytochemistry and morphometric analysis methods. RESULTS: Results presented indicate that 10 mM nicotinamide, when added at the initial stages of differentiation, promoted accelerated progression of ESCs to a neural lineage in adherent monolayer cultures. By 14 days in vitro (DIV), early exposure to nicotinamide was shown to increase the numbers of differentiated ßIII-tubulin-positive neurons. Nicotinamide decreased the proportion of pluripotent stem cells, concomitantly increasing numbers of neural progenitors at 4 DIV. These progenitors then underwent rapid conversion to neurons, observed by a reduction in Sox 1 expression and decreased numbers of neural progenitors in the cultures at 14 DIV. Furthermore, GABAergic neurons generated in the presence of nicotinamide showed increased maturity and complexity of neurites at 14 DIV. Therefore, addition of nicotinamide alone caused an accelerated passage of pluripotent cells through lineage specification and further to non-dividing mature neurons. CONCLUSIONS: Our results show that, within an optimal dose range, nicotinamide is able to singly and selectively direct the conversion of embryonic stem cells to mature neurons, and therefore may be a critical factor for normal brain development, thus supporting previous evidence of the fundamental role of vitamins and their metabolites during early CNS development. In addition, nicotinamide may offer a simple effective supplement to enhance the conversion of stem cells to clinically relevant neurons.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Niacinamida/farmacologia , Animais , Linhagem da Célula , Proliferação de Células/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Proteínas de Fluorescência Verde/genética , Camundongos
19.
Biosci Rep ; 37(4)2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28754805

RESUMO

The E3 ubiquitin ligase RNF168 is a ring finger protein that has previously been identified to play an important regulatory role in the repair of double-strand DNA breaks.  In the present study, an unbiased forward genetics functional screen in mouse granulocyte/ macrophage progenitor cell line FDCP1 has identified E3 ubiquitin ligase RNF168 as a key regulator of cell survival and proliferation. Our data indicate that RNF168 is an important component of the mechanisms controlling cell fate, not only in human and mouse haematopoietic growth factor-dependent cells, but also in the human breast epithelial cell line MCF-7. These observations therefore suggest that RNF168 provides a connection to key pathways controlling cell fate, potentially through interaction with PML nuclear bodies and/or epigenetic control of gene expression. Our study is the first to demonstrate a critical role for RNF168 in the in the mechanisms regulating cell proliferation and survival, in addition to its well-established role in DNA repair.

20.
Oncotarget ; 7(9): 10104-16, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26862727

RESUMO

Growth arrest-specific 5 (GAS5) lncRNA promotes apoptosis, and its expression is down-regulated in breast cancer. GAS5 lncRNA is a decoy of glucocorticoid/related receptors; a stem-loop sequence constitutes the GAS5 hormone response element mimic (HREM), which is essential for the regulation of breast cancer cell apoptosis. This preclinical study aimed to determine if the GAS5 HREM sequence alone promotes the apoptosis of breast cancer cells. Nucleofection of hormone-sensitive and -insensitive breast cancer cell lines with a GAS5 HREM DNA oligonucleotide increased both basal and ultraviolet-C-induced apoptosis, and decreased culture viability and clonogenic growth, similar to GAS5 lncRNA. The HREM oligonucleotide demonstrated similar sequence specificity to the native HREM for its functional activity and had no effect on endogenous GAS5 lncRNA levels. Certain chemically modified HREM oligonucleotides, notably DNA and RNA phosphorothioates, retained pro-apoptotic. activity. Crucially the HREM oligonucleotide could overcome apoptosis resistance secondary to deficient endogenous GAS5 lncRNA levels. Thus, the GAS5 lncRNA HREM sequence alone is sufficient to induce apoptosis in breast cancer cells, including triple-negative breast cancer cells. These findings further suggest that emerging knowledge of structure/function relationships in the field of lncRNA biology can be exploited for the development of entirely novel, oligonucleotide mimic-based, cancer therapies.


Assuntos
Apoptose/efeitos dos fármacos , Hormônios/farmacologia , RNA Longo não Codificante/efeitos dos fármacos , Elementos de Resposta/genética , Apoptose/genética , Apoptose/efeitos da radiação , Sequência de Bases , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Células MCF-7 , Oligonucleotídeos/genética , RNA Longo não Codificante/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Raios Ultravioleta
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