RESUMO
OBJECTIVE: To investigate the effect of maternal zinc deficiency on learning and memory in offspring and the changes in DNA methylation patterns. METHODS: Pregnant rats were divided into zinc adequate (ZA), zinc deficient (ZD), and paired fed (PF) groups. Serum zinc contents and AKP activity in mother rats and offspring at P21 (end of lactation) and P60 (weaned, adult) were detected. Cognitive ability of offspring at P21 and P60 were determined by Morris water maze. The expression of proteins including DNMT3a, DNMT1, GADD45ß, MeCP2 and BDNF in the offspring hippocampus were detected by Western-blot. The methylation status of BDNF promoter region in hippocampus of offspring rats was detected by MS-qPCR. RESULTS: Compared with the ZA and PF groups, pups in the ZD group had lower zinc levels and AKP activity in the serum, spent more time finding the platform and spent less time going through the platform area. Protein expression of DNMT1 and GADD45b were downregulated in the ZD group during P0 and P21 but not P60 compared with the ZA and PF group, these results were consistent with a reduction in BDNF protein at P0 (neonate), P21. However, when pups of rats in the ZD group were supplemented with zinc ion from P21 to P60, MeCP2 and GADD45b expression were significantly downregulated compared with the ZA and PF group. CONCLUSION: Post-weaning zinc supplementation may improve cognitive impairment induced by early life zinc deficiency, whereas it may not completely reverse the abnormal expression of particular genes that are involved in DNA methylation, binding to methylated DNA and neurogenesis.
Assuntos
Metilação de DNA , Desnutrição , Animais , Antígenos de Diferenciação/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Feminino , Hipocampo/metabolismo , Aprendizagem , Desnutrição/metabolismo , Gravidez , Ratos , ZincoRESUMO
A wide range of people in the world use natural remedies as primary approaches against illnesses. Accordingly, understanding the mechanisms of action of phytochemicals has become of great interest. In this context, Centella asiatica L. is extensively used, not only as anti-inflammatory or antioxidant agent but also as brain tonic. On this basis, the purpose of this study was to evaluate whether the chronic administration of C. asiatica L. to adult male rats was able to improve the expression of Bdnf, one of the main mediators of brain plasticity. Moreover, we assessed whether the treatment could affect the cognitive performance in the novel object recognition (NOR) test. We confirmed the presence of the main compounds in the plasma. Furthermore, C. asiatica L. administration induced an increase of Bdnf in the prefrontal cortex, and the administration of the higher dose of the extract was able to improve cognitive performance. Finally, the increase in the preference index in the NOR test was paralleled by a further increase in Bdnf expression. Overall, we highlight the ability of C. asiatica L. to affect brain functions by increasing Bdnf expression and by enhancing the cognitive performance.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Centella/química , Cognição/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Extratos Vegetais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Triterpenos/sangue , Triterpenos/metabolismoRESUMO
Development of antibody-based immunotherapeutics has progressed from direct tumor-targeting, with antibodies such as rituximab, to blocking of immune checkpoints to reactivate antitumor immunity. In addition, bispecific antibodies/antibody fragments are also of great interest in cancer therapy, as these constructs have the ability to redirect immune effector cells to cancer targets and, thereby, enhance therapeutic efficacy. A number of bispecific antibody formats have been reported, with the first FDA-approved bispecific antibody being blinatumomab, a so-called bispecific T cell engager (BiTE), which redirects and potently activates T cell immune responses. Recently, we described an additional novel bispecific antibody derivative, termed RTX-CD47, which was designed to inhibit the innate immune checkpoint CD47-SIRPα only on -positive cancer cells. RTX-CD47 contains two antibody fragments in tandem and has monovalent binding specificity for CD47 and . Only upon dual binding to and CD47 RTX-CD47 blocks CD47 "Don't eat me" signaling. Here, we provide a detailed protocol for the construction and functional evaluation of such a bispecific antibody derivative.
Assuntos
Anticorpos Biespecíficos/farmacologia , Antineoplásicos/farmacologia , Bioensaio/métodos , Neoplasias/tratamento farmacológico , Proteínas Recombinantes de Fusão/imunologia , Animais , Anticorpos Biespecíficos/uso terapêutico , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Antígenos de Diferenciação/metabolismo , Antineoplásicos/uso terapêutico , Bioensaio/instrumentação , Antígeno CD47/genética , Antígeno CD47/imunologia , Antígeno CD47/metabolismo , Células CHO , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Separação Celular/instrumentação , Separação Celular/métodos , Cromatografia de Afinidade/instrumentação , Cromatografia de Afinidade/métodos , Cricetulus , Avaliação Pré-Clínica de Medicamentos/instrumentação , Avaliação Pré-Clínica de Medicamentos/métodos , Células HEK293 , Humanos , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/patologia , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
Frondanol is a nutraceutical lipid extract of the intestine of the edible Atlantic sea cucumber, Cucumaria frondosa, with potent anti-inflammatory effects. In the current study, we investigated Frondanol as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were given 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. The colitis group received oral Frondanol (100 mg/kg body weight/per day by gavage) and were compared with a control group and the DSS group. Disease activity index (DAI) and colon histology were scored for macroscopic and microscopic changes. Colonic tissue length, myeloperoxidase (MPO) concentration, neutrophil and macrophage marker mRNA, pro-inflammatory cytokine proteins, and their respective mRNAs were measured using ELISA and real-time RT-PCR. The tissue content of leukotriene B4 (LTB4) was also measured using ELISA. Frondanol significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue MPO concentrations, neutrophil and macrophage mRNA expression (F4/80 and MIP-2), and pro-inflammatory cytokine content (IL-1β, IL-6 and TNF-α) both at the protein and mRNA level were significantly reduced by Frondanol. The increase in content of the pro-inflammatory mediator leukotriene B4 (LTB4) induced by DSS was also significantly inhibited by Frondanol. It was thus found that Frondanol supplementation attenuates colon inflammation through its potent anti-inflammatory activity.
Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Misturas Complexas/farmacologia , Cucumaria/química , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Misturas Complexas/química , Citocinas/genética , Citocinas/metabolismo , Sulfato de Dextrana , Suplementos Nutricionais , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peroxidase/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
PURPOSE: Using sunflower oil as frying oil increases postprandial oxidative stress, which is considered the main endogenous source of DNA oxidative damage. We aimed to test whether the protective effect of virgin olive oil and oil models with added antioxidants against postprandial oxidative stress may also protect against DNA oxidative damage. METHODS: Twenty obese people received four breakfasts following a randomized crossover design consisting of different oils [virgin olive oil (VOO), sunflower oil (SFO), and a mixed seed oil (SFO/canola oil) with added dimethylpolysiloxane (SOX) or natural antioxidants from olives (SOP)], which were subjected to 20 heating cycles. RESULTS: We observed the postprandial increase in the mRNA levels of p53, OGG1, POLB, and GADD45b after the intake of the breakfast prepared with SFO and SOX, and an increase in the expression of MDM2, APEX1, and XPC after the intake of the breakfast prepared with SFO, whereas no significant changes at the postprandial state were observed after the intake of the other breakfasts (all p values <0.05). We observed lower 8-OHdG postprandial levels after the intake of the breakfast prepared with VOO and SOP than after the intake of the breakfast prepared with SFO and SOX (all p values <0.05). CONCLUSIONS: Our results support the beneficial effect on DNA oxidation damage of virgin olive oil and the oil models with added antioxidants, as compared to the detrimental use of sunflower oil, which induces p53-dependent DNA repair pathway activation.
Assuntos
Antioxidantes/administração & dosagem , Dano ao DNA/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/administração & dosagem , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Idoso , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Antioxidantes/análise , Desjejum , Estudos Cross-Over , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Desoxiguanosina/urina , Dimetilpolisiloxanos/administração & dosagem , Dimetilpolisiloxanos/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade , Azeite de Oliva/administração & dosagem , Azeite de Oliva/análise , Óleos de Plantas/análise , Período Pós-Prandial , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Óleo de Brassica napus/administração & dosagem , Óleo de Brassica napus/análise , Óleo de Girassol/administração & dosagem , Óleo de Girassol/análise , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Precise spatiotemporal epigenetic regulation of the genome facilitates species-typical development; sexual differentiation of the brain by gonadal hormones and sex chromosomes causes extensive epigenetic reprogramming of many cells in the body, including the brain, and may indirectly predispose males and females to different psychiatric conditions. We and others have demonstrated sex differences in DNA methylation, as well as in the enzymes that form, or 'write', this epigenetic modification. However, while a growing body of evidence suggests that DNA methylation undergoes rapid turnover and is dynamically regulated in vivo, to our knowledge no studies have been done investigating whether sex differences exist in the epigenetic 'erasers' during postnatal development. Here we report sex differences in the expression of growth arrest and DNA damage inducible factor ß (Gadd45b), but not family members α (a) or γ (g), in the neonatal and juvenile rodent amygdala.
Assuntos
Tonsila do Cerebelo/crescimento & desenvolvimento , Tonsila do Cerebelo/metabolismo , Antígenos de Diferenciação/metabolismo , Caracteres Sexuais , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Antígenos de Diferenciação/genética , Proteínas de Ciclo Celular/metabolismo , Metilação de DNA/fisiologia , Di-Hidrotestosterona/administração & dosagem , Di-Hidrotestosterona/metabolismo , Estrogênios/administração & dosagem , Estrogênios/metabolismo , Feminino , Hormônios/administração & dosagem , Hormônios/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/crescimento & desenvolvimento , Hipotálamo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Modelos Animais , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Testosterona/administração & dosagem , Testosterona/metabolismo , Proteínas GADD45RESUMO
The IfitmDel mouse lacks all five of the Ifitm genes via LoxP deletion. This animal breeds normally with no obvious defect in development. The IfitmDel animals exhibit a steady and significantly enhanced weight gain relative to wild-type controls beginning about three months of age and under normal feeding conditions. The increased weight corresponds with elevated fat mass, and in tolerance tests they are hyporesponsive to insulin but respond normally to glucose. Both young (4 mo) and older (12 mo) IfitmDel mice have enhanced levels of serum leptin suggesting a defect in leptin/leptin receptor signaling. Analysis of the gene expression profiles in the hypothalamus of IfitmDel animals, compared to WT, demonstrated an altered ratio of Pomc and Npy neuropeptide expression, which likely impairs the satiation response of the IfitmDel animal leading to an increased eating behavior. Also elevated in hypothalamus of IfitmDel mice were pro-inflammatory cytokine expression and reduced IL-10. Anatomical analysis of the hypothalamus using immunohistochemistry revealed that microglia exhibit an abnormal morphology in IfitmDel animals and respond abnormally to Poly:IC challenge. These abnormalities extend the phenotype of the IfitmDel mouse beyond abnormal responses to viral challenge to include a metabolic phenotype and weight gain. Further, this novel phenotype for the IfitmDel mouse could be related to abnormal neuropeptide production, inflammatory status and microglia status in the hypothalamus.
Assuntos
Hipotálamo/metabolismo , Redes e Vias Metabólicas/fisiologia , Microglia/patologia , Obesidade/metabolismo , Idade de Início , Animais , Antígenos de Diferenciação/genética , Citocinas/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Imuno-Histoquímica , Leptina/sangue , Camundongos , Família Multigênica/genética , Neuropeptídeo Y/metabolismo , Obesidade/patologia , Pró-Opiomelanocortina/metabolismoRESUMO
Many animal and human studies indicated that dietary ω-3 fatty acids could have beneficial roles on brain development, memory, and learning. However, the exact mechanisms involved are far from being clearly understood, especially for α-linolenic acid (ALA), which is the precursor for the ω-3 elongation and desaturation pathways. This study investigated the alterations induced by different intakes of flaxseed oil (containing 50% ALA), during gestation and lactation, upon the expression of genes involved in neurogenesis, memory-related molecular processes, and DNA methylation, in the brains of mouse offspring at the end of lactation (postnatal day 19, P19). In addition, DNA methylation status for the same genes was investigated. Maternal flaxseed oil supplementation during lactation increased the expression of Mecp2, Ppp1cc, and Reelin, while decreasing the expression of Ppp1cb and Dnmt3a. Dnmt1 expression was decreased by postnatal flaxseed oil supplementation but this effect was offset by ALA deficiency during gestation. Mecp2 DNA methylation was decreased by maternal ALA deficiency during gestation, with a more robust effect in the lactation-deficient group. In addition, linear regression analysis revealed positive correlations between Mecp2, Reelin, and Ppp1cc, between Gadd45b, Bdnf, and Creb1, and between Egr1 and Dnmt1, respectively. However, there were no correlations, in any gene, between DNA methylation and gene expression. In summary, the interplay between ALA availability during gestation and lactation differentially altered the expression of genes involved in neurogenesis and memory, in the whole brain of the offspring at the end of lactation. The Mecp2 epigenetic status was correlated with ALA availability during gestation. However, the epigenetic status of the genes investigated was not associated with transcript levels, suggesting that either the regulation of these genes is not necessarily under epigenetic control, or that the whole brain model is not adequate for the exploration of epigenetic regulation in the context of this study.
Assuntos
Encéfalo , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Proteína 2 de Ligação a Metil-CpG/genética , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ácido alfa-Linolênico/toxicidade , Análise de Variância , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Masculino , Memória/efeitos dos fármacos , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Proteína Reelina , Estatística como AssuntoRESUMO
The composition of diet is one of the major determining factors for lifespan. The dietary pectins are known to have anti-inflammatory properties and may influence aging and longevity. Here we demonstrate the lifespan-extending effect of the low methyl esterified (LM) commercial pectins CU701 and AU701 in wild-type strain of Drosophila melanogaster. The high methyl esterified (HM) pectin CU201 did not affect lifespan. LM pectin did not increase lifespan of males with a mutation in the Toll adaptor Myd88 gene and in both males and females with a mutation in the NF-κB ortholog Relish. LM pectin CU701 increased imagoes survival in stress conditions (oxidation, hyperthermia and starvation). However, the fertility of LM and HM pectins treated flies decreased. The treatment of the imagoes with LH and HM pectins induced the activation of whole-body expression of genes involved in DNA repair (D-GADD45, mei-9, spn-B), apoptosis (wrinkled/hid) and heat shock response (hsp70Aa). In contrast, the expression of proinflammatory PARP-1 gene decreased. In the intestines LH and HM pectins induced the mRNA expression of the NF-κB-dependent antimicrobial genes Defensin, Drosomycin and Metchnikowin. These results indicate that the observed lifespan-extending effect of the LM pectins may be mediated by intracellular pathways that involve NF-κB signalling and activation of stress resistance genes.
Assuntos
Carboidratos da Dieta/administração & dosagem , Drosophila melanogaster/fisiologia , Longevidade/fisiologia , Pectinas/administração & dosagem , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antígenos de Diferenciação/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Ingestão de Alimentos , Feminino , Fertilidade/genética , Fertilidade/fisiologia , Expressão Gênica , Genes de Insetos , Longevidade/genética , Masculino , Mutação , Receptores Imunológicos/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genéticaRESUMO
Human mid-trimester amniotic fluid stem cells (AFSC) have promising applications in regenerative medicine, being broadly multipotent with an intermediate phenotype between embryonic (ES) and mesenchymal stem cells (MSC). Despite this propluripotent phenotype, AFSC are usually cultured in adherence in a serum-based expansion medium, and how expansion in conditions sustaining pluripotency might affect their phenotype remains unknown. We recently showed that early AFSC from first trimester amniotic fluid, which endogenously express Sox2 and Klf4, can be reprogrammed to pluripotency without viral vectors using the histone deacetylase inhibitor valproic acid (VPA). Here, we show that mid-trimester AFSC cultured under MSC conditions contained a subset of cells endogenously expressing telomerase, CD24, OCT4, C-MYC, and SSEA4, but low/null levels of SOX2, NANOG, KLF4, SSEA3, TRA-1-60, and TRA-1-81, with cells unable to form embryoid bodies (EBs) or teratomas. In contrast, AFSC cultured under human ESC conditions were smaller in size, grew faster, formed colonies, upregulated OCT4 and C-MYC, and expressed KLF4 and SOX2, but not NANOG, SSEA3, TRA-1-60, and TRA-1-81. Supplementation with VPA for 5 days further upregulated OCT4, KLF4, and SOX2, and induced expression of NANOG, SSEA3, TRA-1-60, and TRA-1-81, with cells now able to form EBs and teratomas. We conclude that human mid-trimester AFSC, which may be isolated autologously during pregnancy without ethics restriction, can acquire pluripotent characteristics without the use of ectopic factors. Our data suggest that this medium-dependant approach to pluripotent mid-trimester AFSC reflects true reprogramming and not the selection of prepluripotent cells.
Assuntos
Líquido Amniótico/citologia , Antígenos de Diferenciação/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Células-Tronco Pluripotentes/metabolismo , Ácido Valproico/farmacologia , Animais , Antígenos de Diferenciação/genética , Proliferação de Células , Forma Celular , Células Cultivadas , Meios de Cultura , Células-Tronco Embrionárias/metabolismo , Feminino , Expressão Gênica , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Neoplasias Experimentais/patologia , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/fisiologia , Células-Tronco Pluripotentes/transplante , Gravidez , Segundo Trimestre da Gravidez , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Telômero/metabolismo , Teratoma/patologia , Regulação para Cima/efeitos dos fármacosRESUMO
In this study, we examined the effects of Aloe-emodin (AE) on the inhibition of adipocyte differentiation during 3-isobutyl-1-methylxanthine (IBMX)-induced adipocyte differentiation in human mesenchymal stem cells (hMSCs). AE treatment (5, 10, and 20 µM) of preadipocyte cells resulted in a significant (p < 0.05) decrease in glycerol phosphate dehydrogenase and triglyceride levels as well as an increase in lactate dehydrogenase activity and attenuated lipid accumulation compared with untreated differentiated adipocytes. Using quantitative reverse transcription polymerase chain reaction, we studied the mRNA expression levels of resistin, adiponectin, aP(2), lipoprotein lipase, PPARγ, and tumor necrosis factor-α in hMSCs undergoing adipocyte differentiation; treatment with AE decreased the expression of these adipogenic genes and decreased adipocyte differentiation. In addition, AE suppresses the differentiation of hMSCs into adipocytes by downregulating PPARγ and C/EBPα expressions. AE significantly inhibited hMSCs proliferation and preadipocyte differentiation within the first 2 days of treatment, indicating that the antiadipogenic effect.
Assuntos
Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Aloe/química , Antraquinonas/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Adipócitos/efeitos dos fármacos , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos , Células-Tronco Mesenquimais/fisiologia , PPAR gama/genética , PPAR gama/metabolismo , Fenótipo , Triglicerídeos/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Restricted feeding (RF), a regimen that restricts the duration of food availability with no calorie restriction, entrains the circadian clock in peripheral tissues. Restricted feeding leads to high-amplitude circadian rhythms, which have been shown to promote wellness and reduce disease and inflammatory markers. Retinoids, such as all-trans retinoic acid (ATRA), act as anti-inflammatory agents. Thus far, the effect of ATRA combined with RF on the ability to delay the occurrence of age-associated changes, such as cancer and inflammation, is not known. We measured circadian expression of clock genes, disease marker genes and inflammatory markers in the serum, liver and jejunum in mice fed ad libitum (AL) or RF supplemented with 15 or 250 µg/kg body/day ATRA for 16 weeks. Our results show that ATRA supplementation led to phase shifts and reduced amplitudes in clock genes. Under AL, ATRA reduced the average daily messenger RNA (mRNA) levels of some disease markers, such as liver Afp and jejunum Afp, Alt and Gadd45ß and aspartate transaminase (AST) protein in the serum, but increased the expression level of liver Crp mRNA. Under RF, ATRA reduced the average daily levels of jejunum Alt and Gadd45ß and AST protein in the serum, but increased liver Afp, Alt, Gadd45ß and Arginase mRNA. Altogether, our findings suggest that ATRA strongly affects circadian oscillation and disease marker levels. Moreover, its impact is different depending on the feeding regimen (AL or RF).
Assuntos
Proteínas CLOCK/genética , Restrição Calórica , Relógios Circadianos , Regulação da Expressão Gênica , Tretinoína/farmacologia , Animais , Anti-Inflamatórios , Antígenos de Diferenciação/sangue , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/genética , Proteína C-Reativa/metabolismo , Proteínas CLOCK/metabolismo , Ritmo Circadiano , Marcadores Genéticos , Jejuno/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismoRESUMO
UNLABELLED: Ground glass hepatocytes (GGHs) harboring hepatitis B virus (HBV) pre-S mutants have been recognized as precursor lesions of hepatocellular carcinoma (HCC). Previously, we observed the activation of mammalian target of rapamycin (mTOR) in GGHs and HCCs, together with a decreased expression of HBV surface antigen (HBsAg) in HCC tissues. It is, therefore, hypothesized that the activation of mTOR during HBV tumorigenesis may potentially down-regulate HBsAg expression. In this study, we verified an inverse relationship between the expression of HBsAg and phosphorylated mTOR (p-mTOR) in 13 of 20 paired nontumorous liver and HCC tissues. In vitro, wild-type or mutant pre-S proteins could activate mTOR in the HuH-7 cell line. Interestingly, the up-regulated mTOR, in turn, suppressed HBsAg synthesis at the transcriptional level via the transcription factor, Yin Yang 1 (YY1), which bound to nucleotide 2812-2816 of the pre-S1 promoter. This inhibitory effect by the mTOR signal could be abolished by the knockdown of histone deacetylase 1 (HDAC1). Furthermore, YY1 was physically associated with HDAC1 in a manner dependent on mTOR activation. Collectively, pre-S protein-induced mTOR activation may recruit the YY1-HDAC1 complex to feedback suppress transcription from the pre-S1 promoter. CONCLUSION: The activation of mTOR signal in GGHs may feedback suppress HBsAg synthesis during HBV tumorigenesis and explain the observed decrease or absence of HBsAg in HCC tissues. Therapy using mTOR inhibitors for HCCs may potentially activate HBV replication in patients with chronic HBV infection.
Assuntos
Antígenos de Diferenciação/genética , Antígenos de Superfície da Hepatite B/biossíntese , Vírus da Hepatite B/genética , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/metabolismo , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Transformação Celular Neoplásica/patologia , Células Cultivadas , Retroalimentação Fisiológica , Regulação Viral da Expressão Gênica , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/genéticaRESUMO
Human induced pluripotent stem cells (hiPSCs) have led to an important revolution in stem cell research and regenerative medicine. To create patient-specific neural progenitors (NPs), we have established a homogenous, expandable, and self-renewable population of multipotent NPs from hiPSCs, using an adherent system and defined medium supplemented with a combination of factors. The established hiPSC-NPs highly expressed Nestin and Sox1. These NPs were continuously propagated for ~1 year without losing their potential to generate astrocytes, oligodendrocytes, and functional neurons and maintained a stable chromosome number. Voltage clamp analysis revealed outward potassium currents in hiPSC-NPs. The self-renewal characteristic of the NPs was demonstrated by a symmetrical mode of Nestin-positive cell division. Additionally, these hiPSC-NPs can be easily frozen and thawed in the presence of Rho-associated kinase (ROCK) inhibitor without losing their proliferation, karyotype stability, and developmental potential. The characteristics of our generated hiPSC-NPs provide the opportunity to use patient-specific or ready-to-use hiPSC-NPs in future biomedical applications.
Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/citologia , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular , Forma Celular , Criopreservação , Perfilação da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Proteínas de Filamentos Intermediários/metabolismo , Lidocaína/análogos & derivados , Lidocaína/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Nestina , Neurônios/citologia , Nifedipino/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Fatores de Transcrição SOXB1/metabolismo , Tetraetilamônio/farmacologia , Transcrição GênicaRESUMO
In a previous study, it was reported that yeast hydrolysate (YH) was effective in promoting bone growth in Sprague-Dawley (SD) rats. To further clarify the mechanism of YH, the effects of YH on proliferation, differentiation and gene expression in vitro were investigated using osteoblastic cell lines (MC3T3-E1). Cell proliferation increased significantly as much as 110% of the basal value when cells were treated with 100 µg/mL of YH. Alkaline phosphatase (ALP) activity increased significantly with a YH concentration of 25-100 µg/mL, and the activity increased 152% that of the control at 100 µg/mL. The calcium content increased as much as 129% at 100 µg/mL YH. The gene expression levels of ALP and collagen type II (COL II) significantly increased approximately 1.3-fold and 1.7-fold of control, respectively, at 100 µg/mL. YH increased significantly the mRNA level of bone sialoprotein (BSP) but not in a dose-dependent manner. The mRNA levels of bone morphogenetic proteins (BMP)-2, BMP-4, collagen type I (COL I) and osteonectin (ON) did not increase. In summary, YH increased the proliferation of osteoblasts and directly stimulated ALP and bone matrix proteins (e.g. BSP, COL II), and these increases trigger osteoblastic differentiation (e.g. mineralized nodule formation).
Assuntos
Fosfatase Alcalina/efeitos dos fármacos , Desenvolvimento Ósseo/efeitos dos fármacos , Misturas Complexas/farmacologia , Osteoblastos/efeitos dos fármacos , Saccharomyces cerevisiae/química , Células 3T3 , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Relação Dose-Resposta a Droga , Matriz Extracelular/efeitos dos fármacos , Proteínas Fúngicas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Sialoproteína de Ligação à Integrina/genética , Sialoproteína de Ligação à Integrina/metabolismo , Camundongos , Osteoblastos/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The immune system has developed several regulatory mechanisms to maintain homeostasis of adaptive immune responses. T-cell programmed death (PD)-1 recognition of B7-H1 (PD-L1) expressed on APC and non-lymphoid tissue regulates T-cell activation. We show that B7-H1(-/-) mice exhibit exacerbated proteoglycan (PG)-induced arthritis and increased Th-1 CD4(+) T-cell responses. Unexpectedly, the PG-specific antibody response in B7-H1(-/-) mice was diminished. A reduction in the number of peanut agglutinin(+) GC coincided with a decrease in CD19(+) GL-7(+) CD95(+) GC B cells that was a result of increased caspase-induced apoptosis. The percent of CD38(+) CD138(+) emerging plasma cells was decreased. B7-H1(-/-) mice exhibited an increased frequency of CD4(+) PD-1(hi) CXCR5(hi) ICOS(hi) CD62L(lo) T follicular helper cells that displayed a hyperactive phenotype with increased expression of mRNA transcripts for Bcl6, IL-21, and the apoptosis-inducer molecule FasL. In cell transfer of B7-H1(-/-) cells into SCID mice, non-B and non-T cells were sufficient to normalize the antibody response, T-cell hyperactivity, and the development of PG-induced arthritis. These findings indicate that B7-H1 on non-B and non-T cells signals through PD-1 on T effector cells to prevent excessive activation and reduce autoimmune arthritis. Furthermore, these findings demonstrate a novel role for B7-H1 expression in promoting B-cell survival by regulating the activation of T follicular helper cell.
Assuntos
Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Antígeno B7-1/imunologia , Glicoproteínas de Membrana/imunologia , Peptídeos/imunologia , Plasmócitos/imunologia , Transdução de Sinais/imunologia , Células Th1/imunologia , Animais , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Antígenos de Diferenciação/biossíntese , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Antígenos de Diferenciação/metabolismo , Artrite Experimental/genética , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígeno B7-H1 , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Interleucinas/genética , Interleucinas/imunologia , Interleucinas/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos SCID , Peptídeos/genética , Peptídeos/metabolismo , Plasmócitos/metabolismo , Plasmócitos/patologia , Receptor de Morte Celular Programada 1 , Proteínas Proto-Oncogênicas c-bcl-6 , Transdução de Sinais/genética , Células Th1/metabolismo , Células Th1/patologiaRESUMO
hESCs (human embryonic stem cells) have enormous potential for use in pharmaceutical development and therapeutics; however, to realize this potential, there is a requirement for simple and reproducible cell culture methods that provide adequate numbers of cells of suitable quality. We have discovered a novel way of blocking the spontaneous differentiation of hESCs in the absence of exogenous cytokines by supplementing feeder-free conditions with EHNA [erythro-9-(2-hydroxy-3-nonyl)adenine], an established inhibitor of ADA (adenosine deaminase) and cyclic nucleotide PDE2 (phosphodiesterase 2). hESCs maintained in feeder-free conditions with EHNA for more than ten passages showed no reduction in hESC-associated markers including NANOG, POU5F1 (POU domain class 5 transcription factor 1, also known as Oct-4) and SSEA4 (stage-specific embryonic antigen 4) compared with cells maintained in feeder-free conditions containing bFGF (basic fibroblast growth factor). Spontaneous differentiation was reversibly suppressed by the addition of EHNA, but, upon removing EHNA, hESC populations underwent efficient spontaneous, multi-lineage and directed differentiation. EHNA also acts as a strong blocker of directed neuronal differentiation. Chemically distinct inhibitors of ADA and PDE2 lacked the capacity of EHNA to suppress hESC differentiation, suggesting that the effect is not driven by inhibition of either ADA or PDE2. Preliminary structure-activity relationship analysis found the differentiation-blocking properties of EHNA to reside in a pharmacophore comprising a close adenine mimetic with an extended hydrophobic substituent in the 8- or 9-position. We conclude that EHNA and simple 9-alkyladenines can block directed neuronal and spontaneous differentiation in the absence of exogenous cytokine addition, and may provide a useful replacement for bFGF in large-scale or cGMP-compliant processes.
Assuntos
Adenina/análogos & derivados , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/metabolismo , Adenina/farmacologia , Inibidores de Adenosina Desaminase/farmacologia , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Técnicas de Cultura de Células/métodos , Linhagem Celular , Células-Tronco Embrionárias/citologia , Perfilação da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteína Homeobox Nanog , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Células-Tronco Pluripotentes/citologia , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Antígenos Embrionários Estágio-Específicos/metabolismo , Relação Estrutura-Atividade , Fatores de TempoRESUMO
BACKGROUND: Induced pluripotent stem (iPS) cells, which are functionally comparable to embryonic stem (ES) cells, can be generated from mouse fibroblasts by expression of a defined set of transcription factors Oct4, Sox2, Klf4, and c-Myc. Since iPS cells are generated from somatic cells, they provide an invaluable source of pluripotent stem cells for cell transplantation therapy that does not present ethical problems. However, the reprogramming efficiency is extremely low, and optimal culture conditions for iPS cell derivation have not been clearly defined. METHODS: To generate iPS cells efficiently, we tested 10 different culture conditions: DMEM supplemented with 15% fetal bovine serum (FBS), Knockout DMEM with 15% FBS from Invitrogen, Equitech, or HyClone, DMEM with 15% Knockout Serum Replacement (KSR), and Knockout DMEM with 10%, 15%, 20%, 25%, or 35% KSR. These media all contain 2 mM L-glutamine, 100 µM nonessential amino acids, 100 µM beta-mercaptoethanol, 1000 units ml⻹ leukemia inhibitory factor (LIF), 50 units ml⻹ penicillin, and 50 µg ml⻹ streptomycin. RESULTS: Medium containing Knockout DMEM with 20% KSR permits efficient induction of iPS cells from both mouse embryonic fibroblasts (MEFs) and adult tail tip fibroblasts (TTFs). Mouse iPS cells generated in the condition express ES cell marker genes such as Oct4, Sox2, Rex1, and Nanog at levels comparable to those of ES cells. Furthermore, iPS cells derived form MEFs and adult TTFs can contribute to adult chimeras. CONCLUSION: Our iPS cell induction efficiency is greater than that described in other reports. GENERAL SIGNIFICANCE: These findings provide an important catalyst for examining different culture environments for the generation of iPS cells.
Assuntos
Antígenos de Diferenciação/metabolismo , Técnicas de Cultura de Células/métodos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Fatores de Transcrição/metabolismo , Animais , Antígenos de Diferenciação/genética , Bovinos , Células Cultivadas , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Fator 4 Semelhante a Kruppel , Camundongos , Fatores de Transcrição/genéticaRESUMO
To effectively treat degenerative joint diseases including osteoarthritis (OA), small chemical compounds need to be developed that can potently induce chondrogenic differentiation without promoting terminal differentiation. For this purpose, we screened natural and synthetic compound libraries using a Col2GFP-ATDC5 system and identified oxytetracycline (Oxy) as a chondrogenic compound. Oxy induced cartilaginous matrix synthesis and mRNA expressions of chondrocyte markers in ATDC5 cells. In addition, Oxy suppressed mineralization and mRNA expressions of terminal chondrocyte differentiation markers in ATDC5 cells, primary chondrocytes, and cultured metatarsal bones. Oxy's induction of Col2 mRNA expression was decreased by the addition of Noggin and was increased by the addition of BMP2. Furthermore, Oxy increased mRNA expression of Id1, Bmp2, Bmp4, and Bmp6. These data suggest that Oxy induces chondrogenic differentiation in a BMP-dependent manner and suppresses terminal differentiation. Oxy may be useful for treatment of OA and also for regeneration of cartilage tissue.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Oxitetraciclina/farmacologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Avaliação Pré-Clínica de Medicamentos , Embrião de Mamíferos , Regulação da Expressão Gênica/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Proteína 1 Inibidora de Diferenciação/genética , Proteína 1 Inibidora de Diferenciação/metabolismo , Ossos do Metatarso/efeitos dos fármacos , Ossos do Metatarso/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoartrite/tratamento farmacológico , RNA Mensageiro/metabolismo , Bibliotecas de Moléculas Pequenas , Técnicas de Cultura de TecidosRESUMO
Total saponins of panax ginseng (TSPG) are the major active components in panax ginseng. Dendritic cells (DCs) play an active role in the immunological processes related to atherosclerosis. The purpose of this study was to determine the effect and possible mechanisms of TSPG on the maturation and immune function of DCs. Compared with those untreated, the DCs pre-treated with TSPG and then induced by oxidized-LDL exhibited a significantly lower expression of the maturation-associated markers of CD40, CD86, HLA-DR, and CD1a, together with an increased endocytosic function as well as decreased secretions of cytokine. However, silencing the expression of PPARgamma in DCs, the inhibitory effect of TSPG on the maturation DCs was significantly reduced. In conclusion, TSPG could inhibit the maturation of DCs induced by oxidized-LDL which suggests beneficial effects on atherosclerosis and this effect was partly dependent on the PPARgamma pathway at least.