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INTRODUCTION: One of the mechanisms of epileptgenesis is impairment of inhibitory neural circuits. Several studies have compared neural changes among subtypes of gamma-aminobutyric acid-related (GABAergic) neurons after acquired epileptic seizure. However, it is unclear that GABAergic neural modifications that occur during acquisition process of epileptic seizure. METHODS: Male rats were injected with pentylenetetrazole (PTZ kindling: n = 30) or saline (control: n = 15) every other day to observe the development of epileptic seizure stages. Two time points were identified: the point at which seizures were most difficult to induce, and the point at which seizures were most easy to induce. The expression of GABAergic neuron-related proteins in the hippocampus was immunohistochemically compared among GABAergic subtypes at each of these time points. RESULTS: Bimodal changes in seizure stages were observed in response to PTZ kindling. The increase of seizure stage was transiently suppressed after 8 or 10 injections, and then progressed again by the 16th injection. Based on these results, we defined 10 injections as a short-term injection period during which seizures are less likely to occur, and 20 injections as a long-term injection period during which continuous seizures are likely to occur. The immunohistochemical analysis showed that hippocampal glutamic acid decarboxylase 65 (GAD65) expression was increased after short-term kindling but unchanged after long-term kindling. Increased GAD65 expression was limited to somatostatin-positive (SOM+) cells among several GABAergic subtypes. By contrast, GAD, GABA, GABAAR α1, GABABR1, and VGAT cells showed no change following short- or long-term PTZ kindling. CONCLUSION: PTZ kindling induces bimodal changes in the epileptic seizure stage. Seizure stage is transiently suppressed after short-term PTZ injection with GAD65 upregulation in SOM+ cells. The seizure stage is progressed again after long-term PTZ injection with GAD65 reduction to baseline level.
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Glutamato Descarboxilase , Hipocampo , Interneurônios , Excitação Neurológica , Pentilenotetrazol , Somatostatina , Animais , Masculino , Glutamato Descarboxilase/metabolismo , Excitação Neurológica/efeitos dos fármacos , Excitação Neurológica/metabolismo , Ratos , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Interneurônios/metabolismo , Somatostatina/metabolismo , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/metabolismoRESUMO
The cluster structures of hydrated aminopyrazines, APz-(H2O)n=2-4, in supersonic jets have been investigated measuring the size-selected electronic and vibrational spectra and determined with the aid of quantum chemical calculations. The APz-(H2O)2 structure is assigned as a cyclic N1 type where a homodromic hydrogen-bond chain starts from the amino group and ends at the 1-position nitrogen atom of the pyrazine moiety, corresponding to 2-aminopyridine-(H2O)2. On the other hand, APz-(H2O)n=3,4 has a linear hydrogen-bond network ending at the 4-position one (N4), which resembles 3-aminopyridine-(H2O)n=3,4. The hydrogen-bond network switching from the N1 type to the N4 one provides the accompanying red shifts of the S1-S0 electronic transition that are entirely consistent with those of the corresponding 2-aminopyridine and 3-aminopyridine clusters and also shows the drastically strengthened fluorescence intensity of origin bands in the electronic spectrum. The significant change in the excited-state dynamics is explored by the fluorescence lifetime measurement and the time-dependent density functional theory (TD-DFT) calculation. It is suggested that the drastic elongation of fluorescence lifetimes is due to the change in the electronic structure of the first excited state from nπ* to ππ*, resulting in the decreasing spin-orbit coupling to T1 (ππ*).
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All members of Sophiodela Nakane 1955, hitherto a subgenus of Cicindela Linnaeus, 1758, are reviewed based on the structure of the everted internal sac of the male genitalia. In addition, many species of other genera and subgenera such as the genera Cosmodela Rivalier, 1961, Calochroa Hope, 1838, and Cicindela and its subgenus Pancallia Rivalier, 1961, are also reviewed regarding their reproductive structures. Their relationships are discussed using a comparison between morphological and molecular analyses. Through this study, the taxonomic rank of Sophiodela is raised from a subgenus to a genus as it is demonstrated to be a distinct monophyletic group by both the morphological and molecular analyses. Amongst the species of Sophiodela, S. cyanea Fabricius, 1787 is changed to the subgenus Pancallia. We conclude that the everted internal sac is a useful tool for grouping the genera and subgenera and can be used as a taxonomic character.
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Besouros , Animais , Genitália Masculina , Masculino , FilogeniaRESUMO
OBJECTIVE: The objective of our study was to examine the direct action of insulin-like growth factor-1(IGF-1) signaling on energy homeostasis in myocytes. DESIGN: We studied the IGF-1 stimulation of mitochondrial uncoupling protein 3 (UCP3) expression in the HEK 293 derived cell line TSA201, murine C2C12 skeletal muscle myoblasts, and rat L6 skeletal myoblasts. We also investigated the direct effect of IGF-1 on the Insulin/IGF-1 receptor (IGF-1R)/phosphatidylinositol 3 (PI3)-Akt/forkhead box O4 (FOXO4) pathway using a combination of a reporter assay, semi-quantitative polymerase chain reaction, western blotting, and animal experiments. RESULTS: We demonstrated that IGF-1 regulates UCP3 expression via phosphorylation of FOXO4, which is a downstream signal transducer of IGF-1. UCP3 expression increased with activated FOXO4 in a dose-dependent manner. We also examined the functional FOXO4 binding site consensus sequences and identified it as the -1922â¯bp site in the UCP3 promoter region. UCP3 was also found to be concomitantly expressed with IGF-1 during differentiation of C2C12 myoblasts. Our animal experiments showed that high fat diet induced IGF-1 levels which likely influenced UCP3 expression in the skeletal muscle. CONCLUSION: Our findings demonstrate that that IGF-1 directly stimulates UCP3 expression via the IGF-1/IGF-1R/PI3-Akt/FOXO4 pathway.
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Proteínas de Ciclo Celular/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Músculo Esquelético/metabolismo , Mioblastos Esqueléticos/metabolismo , Proteína Desacopladora 3/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Fatores de Transcrição Forkhead/genética , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Proteína Desacopladora 3/genéticaRESUMO
Mitochondria uncoupling protein2 (UCP2) expressed ubiquitously is a key molecule of energy metabolism. Insulin-like growth factor-1 (IGF-1) is a hormone, a target molecule of growth hormone (GH) signal pathway, which is also known as the drug "mecasermin" for clinical usages. IGF-1 is seemed to be closely related to metabolic diseases, such as adult GH deficiency. However, there has not been reports depicted possible relationship with each other. So, we sought to elucidate the mechanisms by which expression of UCP2 is regulated by IGF-1 via FOXO1. The findings suggested that three sequences in the consensus UCP2 promoter play complementary functional roles in the functional expression of FOXO1. So, we found that FOXO1 is involved in IGF-1-mediated energy metabolism greater than that of direct action of GH via STAT5. Our findings suggested that IGF-1 was involved in energy metabolism by regulating the expression of UCP2 via the PI3K/Akt/FOXO1 pathway.
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Proteína Forkhead Box O1/metabolismo , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Proteína Desacopladora 2/metabolismo , Células 3T3-L1 , Tecido Adiposo/metabolismo , Animais , Metabolismo Energético , Regulação da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Camundongos , Mitocôndrias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Receptor IGF Tipo 1/metabolismo , Fator de Transcrição STAT5/metabolismo , Proteínas Supressoras de Tumor/metabolismoRESUMO
The aim of this cross-sectional study was to use standard automated perimetry to compare fixation variability among the dominant eye fixation, non-dominant eye fixation, and binocular fixation conditions. Thirty-five eyes of 35 healthy young participants underwent standard automated perimetry (Humphrey 24-2 SITA-Standard) in dominant eye fixation, non-dominant eye fixation, and binocular fixation conditions. Fixation variability during foveal threshold and visual field measurement, which was recorded using a wearable eye-tracking glass and calculated using the bivariate contour ellipse area (deg2), was compared among the three fixation conditions. Further, the association of bivariate contour ellipse area with ocular position and fusional amplitude during binocular fixation was analysed. There were no significant differences in bivariate contour ellipse area during foveal threshold measurement among the dominant eye fixation (1.75 deg2), non-dominant eye fixation (1.45 deg2), and binocular fixation (1.62 deg2) conditions. In contrast, the bivariate contour ellipse area during visual field measurement in binocular fixation (2.85 deg2) was significantly lower than the bivariate contour ellipse area in dominant eye fixation (4.62 deg2; p = 0.0227) and non-dominant eye fixation (5.24 deg2; p = 0.0006) conditions. There was no significant difference in bivariate contour ellipse area during visual field measurement between dominant eye fixation and non-dominant eye fixation conditions. There was no significant correlation between bivariate contour ellipse area and either ocular position or fusional amplitude during both foveal threshold and visual field measurements. Thus, fixation variability might be improved in binocular fixation conditions during a long-duration test, such as visual field measurement.
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Fixação Ocular/fisiologia , Fóvea Central/fisiologia , Visão Binocular/fisiologia , Acuidade Visual/fisiologia , Adulto , Estudos Transversais , Dominância Ocular/fisiologia , Feminino , Humanos , Masculino , Testes de Campo Visual/métodos , Campos VisuaisRESUMO
BACKGROUND: Adventitious root formation is an essential physiological process for successful propagation of cuttings in various plant species. Because coniferous species are highly heterozygous, propagation of cuttings is of great practical use in breeding. Although various factors influence adventitious root formation, little is known of the associated regulatory mechanisms. Whereas adventitious roots generally form from the base of cuttings, this process is accompanied by physiological changes in leaves, which supply assimilates and metabolites. Herein, we present microarray analyses of transcriptome dynamics during adventitious root formation in whole cuttings in the coniferous species, Cryptomeria japonica. RESULTS: Temporal patterns of gene expression were determined in the base, the middle, and needles of cuttings at eight time points during adventitious root formation. Global gene expression at the base had diverged from that in the middle by 3-h post-insertion, and changed little in the subsequent 3-days post-insertion, and global gene expression in needles altered characteristically at 3- and 6-weeks post-insertion. In Gene Ontology enrichment analysis of major gene clusters based on hierarchical clustering, the expression profiles of genes related to carbohydrates, plant hormones, and other categories indicated multiple biological changes that were involved in adventitious root formation. CONCLUSIONS: The present comprehensive transcriptome analyses indicate major transcriptional turning and contribute to the understanding of the biological processes and molecular factors that influence adventitious root formation in C. japonica.
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Cryptomeria/genética , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Cryptomeria/crescimento & desenvolvimento , Metabolismo Energético/genética , Perfilação da Expressão Gênica , Melhoramento Vegetal , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismoRESUMO
Two protected 14,15-secoergostane derivatives suitable as pivotal intermediates for the synthesis of strophasterols A and B, anti-MRSA and neuronal cell-protecting natural products bearing a recently discovered strophastane skeleton, have been synthesized by two different routes. The first approach employed an oxidative cleavage of an α-hydroxy ketone intermediate with the Jones reagent as the key step to reach the targeted secoergostane from ergosterol in ten steps. In the second approach, an unprecedented reaction cascade composed of four reactions enabled us to obtain the secoergostane more efficiently in six steps.
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Produtos Biológicos/química , Ergosterol/análogos & derivados , Esteróis/síntese química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Ergosterol/química , Estrutura Molecular , Oxirredução , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho , Esteróis/químicaRESUMO
OBJECTIVE: We evaluated the direct action of GH signaling in energy homeostasis in myocytes. DESIGN: We investigated the GH-induced expression of UCP3 in human embryonic kidney 293 cells, human H-EMC-SS chondrosarcoma cells, murine C2C12 skeletal muscle myoblasts, and rat L6 skeletal muscle cells, as well as its direct effect on the GHR/JAK/STAT5 pathway using a combination of a reporter assay, real-time quantitative polymerase chain reaction, and western blotting. RESULTS: We demonstrated that the regulation of energy metabolism by GH involves UCP3 via activated STAT5, a signal transducer downstream of GH. UCP3 expression increased with STAT5 in a dose-dependent manner and was higher than that of UCP2. We confirmed the functional STAT5 binding site consensus sequences at -861 and -507â¯bp in the UCP3 promoter region. CONCLUSION: The results suggest that GH stimulates UCP3 directly and that UCP2 and that UCP3 participate in the signal transduction pathway that functions downstream of the GHR/JAK/STAT.
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Condrossarcoma/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Músculo Esquelético/metabolismo , Mioblastos Esqueléticos/metabolismo , Proteína Desacopladora 3/metabolismo , Animais , Células Cultivadas , Condrossarcoma/genética , Condrossarcoma/patologia , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Camundongos , Músculo Esquelético/citologia , Mioblastos Esqueléticos/citologia , Ratos , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Proteína Desacopladora 3/genéticaRESUMO
OBJECTIVE: The transition of white adipocytes to beige cells (a phenomenon referred to as browning or beigeing) during obesity has been previously reported. Our study aimed to examine the mechanisms through which obesity induced by a high fat diet (HFD) affects uncoupling protein 1 (UCP1) expression via signal transduction and activator of transcription 5 (STAT5s). DESIGN: Seven-week-old male C57BL/6J mice were fed a normal or HFD for 11weeks. Body weight, white adipose tissue weight, and blood lipid and glucose levels were measured. To unveil the molecular mechanisms of UCP1 expression in adipose tissue, we performed further studying 3T3-L1 cells using qRT-PCR. We also measured UCP1 promoter activity in the TSA201 cell line using a dual luciferase assay. In addition, we analyzed the predicted consensus sequences for STAT5 binding in the UCP1 promoter region. RESULTS: Mice fed an HFD had higher body weight and intra-abdominal adipose tissues weight and a higher expression of UCP1, GH receptor (GHR), STATs, suppressors of cytokine signaling (SOCSs), and cytokine-inducible SH2-containing protein (CISH) compared to control mice. In 3T3-L1 cell studies, GH induced phosphorylation of the STAT5, SOCSs, CISH and UCP1 expressions. UCP1 promoter activity was associated with constitutively active STAT5 in a dose-dependent manner. We confirmed functional STAT5 binding sites at -425, -279, and -178bp of the UCP1 promoter. CONCLUSION: We suggest that endogenous GH induces UCP1 expression in adipose tissue via STAT5.
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Tecido Adiposo Branco/metabolismo , Hormônio do Crescimento/metabolismo , Fator de Transcrição STAT5/genética , Proteína Desacopladora 1/metabolismo , Células 3T3-L1 , Gordura Abdominal/metabolismo , Adipócitos/metabolismo , Animais , Sítios de Ligação , Glicemia/metabolismo , Peso Corporal , Fosfatos de Cálcio/metabolismo , Dieta Hiperlipídica , Células HEK293 , Humanos , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Fosforilação , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Proteína Desacopladora 1/genéticaRESUMO
Two epimeric rearranged ergostanes, strophasterolsâ A and B, with an unprecedented carbon skeleton were synthesized from ergosterol, both in 17 steps via a common secosteroidal intermediate. The conversion of ergosterol into the pivotal intermediate involved an efficient acid-catalyzed double-bond migration from ringâ B to ringâ D, oxidative cleavage of the double bond, and a completely diastereoselective acyl radical cyclization to form an isolated cyclopentanone ring unique to this recently discovered family of steroidal compounds produced by mushrooms. The intermediate was transformed stereodivergently into two epimeric cyclopentane derivatives through hydrogenation using two types of catalysts. One epimer was elaborated into strophasterolâ B by utilizing peracid oxidation of an iodide to provide an epoxide directly, and the other epimer was elaborated into strophasterolâ A, which is known to be a suppressor of endoplasmic reticulum stress.
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Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in-field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in-field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes.
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Agricultura/métodos , Artrópodes , Biodiversidade , Ecossistema , AnimaisRESUMO
Polyglucosan bodies (PGB) in the prostate of aged dogs without neurological signs were examined by light microscopy, histochemistry and immunohistochemistry. Prostatic PGB were round or oval and slightly basophilic. Most of the bodies were situated within the stromal smooth muscle cells. PGB were intensely positive for PAS, Best's carmine, Lugol's iodine and Grocott's methenamine silver method. Moreover, canine prostatic PGB were immunoreactive for monoclonal antibodies raised against human polyglucosan. The frequency of PGB in the smooth muscle cells was significantly correlated with the age of dogs. The occurrence of PGB in the canine prostate might be a non-specific finding related to ageing.
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Envelhecimento/patologia , Cães , Glucanos/metabolismo , Corpos de Inclusão/metabolismo , Músculo Liso/patologia , Próstata/patologia , Animais , Imuno-Histoquímica , MasculinoRESUMO
BACKGROUND: The impact of vitamin D3 (VD3) on obesity has been reported in the past. Our study was aimed at investigating the possible mechanisms by which VD3 affects obesity induced by a high fat diet. METHODS: Eight-week-old C57BL/6 J male mice were fed a normal- or high-fat diet for 9 weeks and were treated with a gavage of vehicle (corn oil) or cholecalciferol (50 µg/kg, daily). Body weight, white adipose tissue weight, blood lipid and glucose levels were measured. In addition, we investigated the expression of 1,25(OH)2D3 (calcitriol)/VDR-regulated genes involved in energy and lipid metabolism, such as of uncoupling protein 3 (UCP3), by using qRT-PCR in the liver, adipose tissue, skeletal muscle and C2C12, L6, and H-EMC-SS cells. We also measured UCP3 promoter transcription in the same cell lines using a Dual Luciferase Assay. Furthermore, we analyzed the binding site consensus sequences of VDR on the UCP3 promoter. RESULTS: Mice consuming a high-fat diet treated with cholecalciferol had lower body weight and adipose tissue weight and higher expression of UCP3 compared to the other treatment groups. Changes in the expression of genes correlated with calcitriol/VDR. Luciferase activity was dose-dependently associated with calcitriol/VDR levels. We confirmed the functional VDR binding site consensus sequences at -2200, -1561, -634, and +314 bp in the UCP3 promoter region. CONCLUSION: We suggest that VD3/VDR inhibits weight gain by activating UCP3 in the muscles.
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Calcitriol/farmacologia , Colecalciferol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Receptores de Calcitriol/metabolismo , Proteína Desacopladora 3/biossíntese , Animais , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Masculino , Camundongos , Proteínas Musculares/genética , Músculo Esquelético/patologia , Obesidade/induzido quimicamente , Obesidade/genética , Obesidade/patologia , Receptores de Calcitriol/genética , Proteína Desacopladora 3/genéticaRESUMO
The active form of vitamin D3 (1α,25(OH)2D3, also known as calcitriol) controls the expression of target genes via the vitamin D receptor (VDR). Vitamin D-dependent rickets type II (VDDRII) is a congenital disease caused by inactivating mutations in the VDR The condition is treated with high doses of calcitriol, but the therapeutic effects of other synthetic VD3 analogs have not yet been investigated. In the present study, we analyzed the transcriptional activity of seven different VD3 analogs with VDRs carrying ligand-binding domain mutations identified in VDDRII patients. Wild-type VDR (WT-VDR) and seven mutant VDRs were expressed in TSA201 human embryonic kidney cells, HepG2 human liver cancer cells, and MC3T3-E1 mouse calvaria cells, and their transcriptional activation with VD3 analogs were analyzed by performing transient expression assays, western blotting, and quantitative real-time PCR. The results demonstrated that falecalcitriol stimulated significantly higher transcriptional activation of the WT-VDR and some mutant VDRs than did calcitriol. Calcitriol showed almost no transcriptional activation of the VDR with the I268T mutation identified in a severe case of VDDRII, whereas falecalcitriol caused a dose-dependent increase in the activation of this mutant VDR. Our findings demonstrate that falecalcitriol has a VDR activation profile distinct from that of calcitriol and may exhibit therapeutic effects even on difficult-to-treat VDDRII cases resistant to calcitriol. It is also possible that VDDRII patients responding to high doses of calcitriol could be appropriately treated with low doses of falecalcitriol.
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Colecalciferol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Mutação , Receptores de Calcitriol/genética , Transcrição Gênica , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Animais , Calcitriol/análogos & derivados , Calcitriol/farmacologia , Linhagem Celular , Colecalciferol/análogos & derivados , Humanos , Camundongos , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Calcitriol/metabolismoRESUMO
OBJECTIVE: To determine if and how growth hormone (GH) signaling is involved in energy metabolism. DESIGN: We used human embryonic kidney TSA201 cells, human H-EMC-SS chondrosarcoma cells, rat L6 skeletal muscle cells, and murine C2C12 skeletal muscle myoblasts to investigate GH-induced expression of uncoupling protein2 (UCP2) to the GHR/JAK/STAT5 pathway by a combination of a reporter assay, electrophoretic mobility shift assay (EMSA), real-time quantitative PCR, Western blotting. RESULTS: We demonstrated that the regulation energy metabolism, which was hypothesized to be directly acted on by GH, involves UCP2 via activated STAT5B, a signal transducer downstream of GH. We also showed that the sequence at the -586 'TTCnGA' may function as a novel putative consensus sequence of STAT5s. CONCLUSION: The results suggest that GH regulates energy metabolism directly in myocytes and that UCP2 participates in the signal transduction pathway that functions downstream of the GHR/JAK/STAT.
Assuntos
Condrossarcoma/metabolismo , Metabolismo Energético/genética , Hormônio do Crescimento/metabolismo , Janus Quinase 2/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fator de Transcrição STAT5/metabolismo , Proteína Desacopladora 2/genética , Animais , Western Blotting , Linhagem Celular Tumoral , Condrossarcoma/genética , Ensaio de Desvio de Mobilidade Eletroforética , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Janus Quinases/metabolismo , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Receptores da Somatotropina/metabolismo , Transdução de SinaisRESUMO
In regenerative medicine using transplantation of mesenchymal stem cells (MSCs), the importance of regulating the quality of MSCs has been well recognized; however, there is little information concerning the relationship between the population doubling level (PDL) and the stemness of MSCs in equine medicine. In this study, we showed that the amount of glycosaminoglycan (GAG) secreted by bone marrow-derived MSCs (BMSCs) decreases with increase of PDL. Enzymatic digestion and two-dimensional electrophoresis revealed that a main component of GAG produced by BMSCs was hyaluronan with a small amount of chondroitin sulfate. Increase of PDL downregulated the expression of MSC CD markers, including CD44, CD73, CD90, CD105, and CD146, along with loss of differentiation capacity. Thus, the effect of hyaluronan supplement to the growth medium on both expression of CD markers and the tri-lineage potential of BMSCs was evaluated. Expression of CD73 and CD90 was preserved by continuous addition of hyaluronan to the growth medium, whereas mRNA levels corresponding to CD44, CD105 and CD146 were not preserved by supplementation of hyaluronan. BMSCs subcultured with hyaluronan-supplemented growth medium to PDL-12 showed osteogenic capacity, however adipogenic and chondrogenic activities at PDL-12 were not preserved by exogenous hyaluronan. These results suggest that downregulation of CD44, CD105 and CD146 might not affect the osteogenic capacity. Taken together, the results suggested that supplementation of hyaluronan to the growth medium might be effective at maintaining the osteogenic capacity of equine BMSCs.
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We report a novel method to prepare silicon quantum dots (Si-QDs) having excellent stability in water without organic-ligands by simultaneously doping phosphorus and boron. The codoped Si-QDs in water exhibit bright size-tunable luminescence in a biological window. The luminescence of codoped Si-QDs is very stable under continuous photoexcitation in water.
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To investigate the effect of inhomogeneity in the first network on the enormously high toughness of double network (DN) gels, we fabricated DN gels with a nearly homogeneous first network structure (named St-TPEG/PAAm DN gels) based on tetra-PEG (TPEG) gels via a molecular stent method. The St-TPEG/PAAm DN gels also show excellent mechanical properties and yielding-like phenomena comparable to conventional DN gels. This result demonstrates that the inhomogeneity within the first network is not essential for the specific toughening mechanism of DN gels. On the other hand, the St-TPEG/PAAm DN gels and conventional DN gels undergo substantially different fracture processes before the yielding point. This suggests the importance of a "homogenization process" for the yielding of DN gels. Since the St-TPEG/PAAm DN gels consist of a well-defined first network, they may serve as model DN gels in the future for further studies on fracture processes of DN gels.
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We have developed a novel drug delivery system (DDS) using an antitumor agent, α-tocopheryl succinate (TS). TS has attracted attention as a unique anti-cancer drug for its ability to induce apoptosis in various cancer cells. Furthermore, TS itself readily forms nanovesicles (TS-NVs) and is a prospective tool for use as an antitumor DDS. However, TS-NVs are unstable for encapsulating drugs and passive targeting delivery to tumor tissue via enhanced permeation and retention effect. Therefore, to improve the stability of vesicles, we developed a novel nanovesicle consisting of TS and egg phosphatidylcholine (TS-EPC-NVs). The stability of vesicles of TS-EPC-NVs was significantly higher than that of TS-NVs. As a result, the in vivo antitumor activity of TS-EPC-NVs was more potent than that of TS-NVs. The enhanced antitumor activity of TS-EPC-NVs was found to be due to its effective intratumoral distribution. Moreover, the in vitro anticancer efficiency of TS-EPC-NVs increased seven-fold. We suggest that the improvement is due to homogenous cellular uptake and enhanced cytosolic delivery of the nanovesicles via alteration of intracellular trafficking. Furthermore, TS-EPC-NVs encapsulating siRNA showed significant knockdown efficiency. In summary, TS-EPC-NVs represent a novel and attractive drug delivery system. The system shows antitumor activity of the encapsulated drug and the carrier itself.