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The grasscutter (also known as the greater cane rat; Thryonomys swinderianus) is a large rodent native to West Africa that is currently under domestication process for meat production. However, little is known about the physiology of this species. In the present study, aiming to provide information about gut microbiota of the grasscutter and better understand its physiology, we investigated the intestinal microbiota of grasscutters and compared it with that of other livestock (cattle, goat, rabbit, and sheep) using 16S rRNA metagenomics analysis. Similar to the other herbivorous animals, bacteria classified as Bacteroidales, Clostridiales, Ruminococcaceae, and Lachnospiraceae were abundant in the microbiome of grasscutters. However, Prevotella and Treponema bacteria, which have fiber fermentation ability, were especially abundant in grasscutters, where the relative abundance of these genera was higher than that in the other animals. The presence of these genera might confer grasscutters the ability to easily breakdown dietary fibers. Diets for grasscutters should be made from ingredients not consumed by humans to avoid competition for resources and the ability to digest fibers may allow the use of fiber-rich feed materials not used by humans. Our findings serve as reference and support future studies on changes in the gut microbiota of the grasscutter as domestication progresses in order to establish appropriate feeding methods and captivity conditions.
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Black soldier fly (BSF) larvae and pre-pupae could be satisfactorily raised on household organic waste and used as poultry feed, offering a potential sustainable way to recycle untapped resources of waste. The present study was conducted to determine if whole (non-defatted) BSF larvae and pre-pupae raised on experimental household waste could substitute soybean meal and oil as ingredients for laying hen diets. While no significant differences in feed intake and the egg-laying rate of hens were observed throughout the experiment, egg weight and eggshell thickness were greater in the pre-pupae-fed group than in the other groups. Moreover, although diversity of the cecal microbiota was significantly higher in the pre-pupae-fed than in the control group, no significant differences in bacterial genera known to cause food poisoning were observed when comparing the treatment groups. Nonetheless, Lactobacillus and Bifidobacterium populations were significantly lower in the treatment than in the control group. Fat content in BSF was possibly related with the changes in the cecal microbiota. Hence, since BSF fat was deficient in essential fatty acids, special attention should be paid to the fat content and its fatty acid composition in the case of regular inclusion of BSF larvae and pre-pupae oil as an ingredient in poultry diets.
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BACKGROUND: The standard for rotational alignment of the tibial component in total knee arthroplasty (TKA) remains unclear. Cases often require positioning of the tibial component, prioritizing adequate coverage of resected bone surface rather than alignment with the tibial rotational axis. We investigated tibial component position in TKA, prioritizing maximum coverage of resected bone surface, and evaluated the correlation with the tibial anteroposterior (AP) axis. METHODS: We analyzed preoperative computed tomography images for primary TKA in 106 cases and 157 knees, using three-dimensional planning software. Tibial component position prioritizing maximum coverage of resected bone surface was simulated, and results were compared with the AP axis. Rotational alignment angle was defined as that between a line perpendicular to the tibial AP axis and a line connecting the posterior edge of the tibial component. RESULTS: The simulated tibial component was more externally rotated by a mean 4.5° ± 4.2°. The alignment angle showed normal distribution, but variability was large, ranging from 5.1° internal rotation to 16.2° external rotation. In 138 of 157 (87.9 %) knees, the tibial component was positioned in the externally rotated position with respect to the AP axis. The tibial component was aligned within the medial one-third of the patellar tendon in 122 of 157 (77.7 %) knees. CONCLUSIONS: The tibial component aligned using coverage prioritizing was externally rotated, although large variability was observed. Rotational alignment was optimal in 79 % of cases when the tibial component was aligned with coverage prioritizing, but hyperexternal rotation was observed in patients with severe knee deformation.
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Artroplastia de Reemplazo de Rodilla/métodos , Tibia/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Desviación Ósea/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/cirugía , Ligamento Rotuliano/diagnóstico por imagen , Ligamento Cruzado Posterior/diagnóstico por imagen , Cuidados Preoperatorios , Rotación , Tomografía Computarizada por Rayos XRESUMEN
Excessive intake of sugar-rich foods leads to metabolic syndrome. D-Psicose (Psi) not commonly found in nature, is noncalorie sweetener with a suppressive effect on the blood glucose level. Thus, Psi has the potential to be utilized as a sucrose (Suc) replacer in sugar-rich foods, including meringue-based confectionery (MBC). In this study, we investigated the effect of Psi on the physical and chemical properties of meringue. Meringue was made by whipping egg white and Suc (at a weight ratio of 1:1) and baking at 93 °C for 2 h. Thirty percent of the total weight of Suc was replaced with D-ketohexoses such as Psi, D-fructose, D-tagatose, and D-sorbose. The meringues containing D-ketohexoses had higher specific volume than the meringue not containing D-ketohexoses (Ct-meringue). Baking of meringue caused differences between Psi and the other D-ketohexose meringues. Meringue containing Psi (P30-meringue) had the highest breaking stress (7.00 × 10(5) N/m(2)) and breaking strain (4.40%), resulting in the crunchiest texture. In addition, P30-meringue also had the highest antioxidant activity (491.84 µM TE/mg-meringue determined by ABTS method) and was the brownest due to a Maillard reaction occurring during baking. The replacement of Suc with Psi improved the characteristics of baked meringue. Thus, Psi was found to be useful in modifying the physical and chemical properties of MBC.
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Clara de Huevo , Fructosa/química , Edulcorantes no Nutritivos/química , Manipulación de Alimentos/métodos , Hexosas/química , Reacción de Maillard , Oxidación-Reducción , Sacarosa/químicaRESUMEN
We comprehensively evaluated meat quality in chickens fed a diet consisting of wood charcoal and vinegar (WCV) using food scientific and histological approaches. In culled hens, lipid and fatty acid in Musculus semimembranosus, cooking loss and sensory tests of whole thigh meat, and meat texture of breast meat were observed. In male broilers, cross section of M. semimembranosus was used for observations on muscle area, perimysium, non-collagen total protein and total collagen content, and anti-collagen I and III reactions. In frozen male broilers, conventional morphology of M. semimembranosus as well as chicken anti-collagen III reaction to selected muscles of thigh meat and breast meat were compared between the control and WCV-fed birds. Increased lipid and fatty acids, decreased cooking loss, high score in total evaluation for sensory test of thigh meat, and decreased meat texture values were observed for culled hens fed WCV. The higher values of muscle area, total collagen and collagen III were observed for broilers fed WCV. No perimysium collapse for M. semitendinosus or increased collagen III reactions of M. tensor fasciae latae, the flexor muscle group and M. pectoralis superficialis were observed for frozen muscles in the WCV group. These total results suggest that WCV produces palatable and tender meat by increasing collagen III.
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Ácido Acético/administración & dosificación , Ácido Acético/farmacología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Carbón Orgánico/administración & dosificación , Carbón Orgánico/farmacología , Pollos/metabolismo , Colágeno Tipo III/análisis , Colágeno Tipo III/metabolismo , Suplementos Dietéticos , Carne/análisis , Animales , Ácidos Grasos/metabolismo , Femenino , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Músculo Esquelético/metabolismoRESUMEN
Collagen in an eggshell membrane is important for egg preservation, medical burn treatment and manufacturing of cosmetics. Because collagen in the membrane is little, it is a need to improve the accumulation in the membrane to develop these applications. Wood charcoal powder with vinegar (WCV) is a natural substance that improves poultry production. In hen fed with WCV, total collagen in the eggshell membrane increased with an increase in dietary WCV and significantly increased in the 1.0% WCV group (p < 0.05). Scanning and light microscopic images revealed that this group had thicker eggshell membranes and a fine mesh structure composed of finer and more densely distributed fibres than in the control. Eggs from WCV group showed slow Haugh unit decrease during egg storage and the decrease correlated with total collagen in eggshell membrane. In intact chicken, type I and type III collagens were found in different specific locations in the oviduct but not in the membrane. The finding that collagen accumulates in the eggshell membrane under WCV feeding suggests that feeding chicken with WCV will permit long-term storage of eggs in poultry production, and the increased volume of total collagen will facilitate its application in medicine and cosmetics.
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Ácido Acético/farmacología , Carbón Orgánico/farmacología , Pollos/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo I/metabolismo , Dieta/veterinaria , Cáscara de Huevo/efectos de los fármacos , Madera/química , Animales , Western Blotting , Cáscara de Huevo/citología , Cáscara de Huevo/metabolismo , Cáscara de Huevo/ultraestructura , Femenino , Técnica del Anticuerpo Fluorescente , Membranas/efectos de los fármacos , Membranas/metabolismo , Membranas/ultraestructura , Oviductos/efectos de los fármacos , Oviductos/metabolismo , PolvosRESUMEN
Hypothalamic terminals were investigated in the rat posterior pituitary (PP). Injection of wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) and co-injection of WGA-HRP with Rab3A-siRNA were made into the hypothalamus, respectively. Additional injection of WGA-HRP was made into the hypothalamus in the animals exposed to ethanol. These injections resulted in heavy labeling of fibers exclusively confined to the PP. Ultrastructural observations showed terminals, fibers, pituicytes, capillaries and vascular spaces in the PP. Although the majority of terminals were observed to contain large dense core vesicles (LDCVs) and HRP-reaction products (HRP-RPs), exocytosis of LDCVs in close proximity to cell membrane was not found. Interestingly, a few terminals showed alteration of cell membrane called "apocrine-like structure" containing LDCV and RP. The narrow neck portion of the structure gave the appearance that it may have been in some stage of separating from terminals. Other remarkable feature was that terminals occasionally reveal the structure of "leakage" of RP discharged into vascular spaces crossing cell membrane. Such hormone-releasing mechanism might be involved in one of "diacrine-like secretion". In the present study secretion-related structures of hypothalamic terminals in the PP are quite different from normal vesicular exocytosis.
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Neurohipófisis/inervación , Terminales Presinápticos/metabolismo , Animales , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Neurohipófisis/ultraestructura , Ratas , Ratas Wistar , Aglutinina del Germen de Trigo-Peroxidasa de Rábano Silvestre ConjugadaRESUMEN
AIMS: The effects of ethanol exposure on synaptic structure were investigated in the nucleus of solitary tract (NST) in rats, using the horse-radish peroxidase (HRP) method. METHODS: Eight-week-old experimental rats were allowed free access to a liquid diet containing ethanol for 3 weeks, while controls were given an isocaloric diet. Some of the control and experimental animals were given an injection of wheat germ agglutinin conjugated with HRP (WGA-HRP) into the vagus nerve toward the end of the treatment period. After the treatment, the neuropil region of the NST was examined under an electron microscope. RESULTS: We observed that a few terminals were characterized by deep indentation of axodendritic membranes into the post-synaptic neurons. This appeared to be similar to that commonly seen in exocrine glands. Interestingly, the indented portion often contained various sizes of vacuoles and flattened cisternae. HRP-reaction product (RP) transported to terminals was recognized easily as an electron-dense lysosomal substance when lead citrate staining was omitted. Terminals containing HRP-RP also revealed quite a similar structure with indentation of axodendritic membranes as described earlier. The results are considered to confirm that terminals forming 'apocrine-like structures' observed in the ethanol-fed animals with no injection of WGA-HRP originate from afferent fibers of the vagus nerve. CONCLUSION: The present study suggests the possibility that the alteration of the synaptic structure induced by ethanol exposure can lead to the neuronal transcytosis of materials including proteins which is different from the normal vesicular exocytosis involved in chemical synaptic transmission.
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Etanol/administración & dosificación , Sinapsis/efectos de los fármacos , Sinapsis/ultraestructura , Transcitosis/efectos de los fármacos , Animales , Etanol/toxicidad , Masculino , Ratas , Ratas Wistar , Núcleo Solitario/efectos de los fármacos , Núcleo Solitario/metabolismo , Núcleo Solitario/ultraestructura , Sinapsis/metabolismo , Transcitosis/fisiologíaRESUMEN
The hypothesis that apoptotic factors play some roles in the denucleation of erythroblasts has been confirmed by the immunohistological detection of both phosphatidylserine and thrombospondin as phagocytosis-inducing factors in general apoptotic events. Both phosphatidylserine and thrombospondin were detected on the surface of cell membrane of mature erythroblasts, while thrombospondin was also detected in more immature erythroblasts. The intensities of their immune reactions increased as the erythroids matured. During denucleation, the positivities of both phosphatidylserine and thrombospondin were restricted on the surface of the cell membrane surrounding the protruding nuclei. Thus, the apoptotic process involves denucleation of erythroblasts and phosphatidylserine, and thrombospondin acts as phagocytosis-inducing factors in the denucleation event.
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Apoptosis/fisiología , Eritroblastos/citología , Eritropoyesis/fisiología , Fosfatidilserinas/metabolismo , Trombospondinas/metabolismo , Animales , Eritroblastos/metabolismo , Inmunohistoquímica , Masculino , Ratas , Ratas WistarRESUMEN
Hypoxia promotes neural stem cell proliferation, the mechanism of which is poorly understood. Here, we have identified the nuclear orphan receptor TLX as a mediator for proliferation and pluripotency of neural progenitors upon hypoxia. We found an enhanced early protein expression of TLX under hypoxia potentiating sustained proliferation of neural progenitors. Moreover, TLX induction upon hypoxia in differentiating conditions leads to proliferation and a stem cell-like phenotype, along with coexpression of neural stem cell markers. Following hypoxia, TLX is recruited to the Oct-3/4 proximal promoter, augmenting the gene transcription and promoting progenitor proliferation and pluripotency. Knockdown of Oct-3/4 significantly reduced TLX-mediated proliferation, highlighting their interdependence in regulating the progenitor pool. Additionally, TLX synergizes with basic FGF to sustain cell viability upon hypoxia, since the knockdown of TLX along with the withdrawal of growth factor results in cell death. This can be attributed to the activation of Akt signaling pathway by TLX, the depletion of which results in reduced proliferation of progenitor cells. Cumulatively, the data presented here demonstrate a new role for TLX in neural stem cell proliferation and pluripotency upon hypoxia.
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Células Madre Adultas/metabolismo , Hipocampo/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Células Madre Pluripotentes/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Células Madre Adultas/citología , Animales , Hipoxia de la Célula/fisiología , Proliferación Celular , Supervivencia Celular/fisiología , Regulación de la Expresión Génica/fisiología , Técnicas de Silenciamiento del Gen , Hipocampo/citología , Humanos , Ratones , Factor 3 de Transcripción de Unión a Octámeros/genética , Receptores Nucleares Huérfanos , Células Madre Pluripotentes/citología , Regiones Promotoras Genéticas/fisiología , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Transducción de Señal/fisiologíaRESUMEN
The orphan nuclear receptor TLX has been proposed to act as a repressor of cell cycle inhibitors to maintain the neural stem cells in an undifferentiated state, and prevents commitment into astrocyte lineages. However, little is known about the mechanism of TLX in neuronal lineage commitment and differentiation. A majority of adult rat hippocampus-derived progenitors (AHPs) cultured in the presence of FGF express a high level of TLX and a fraction of these cells also express the proneural gene MASH1. Upon FGF withdrawal, TLX rapidly decreased, while MASH1 was intensely expressed within 1h, decreasing gradually to disappear at 24h. Adenoviral transduction of TLX in AHP cells in the absence of FGF transiently increased cell proliferation, however, later resulted in neuronal differentiation by inducing MASH1, Neurogenin1, DCX, and MAP2ab. Furthermore, TLX directly targets and activates the MASH1 promoter through interaction with Sp1, recruiting co-activators whereas dismissing the co-repressor HDAC4. Conversely, silencing of TLX in AHPs decreased beta-III tubulin and DCX expression and promoted glial differentiation. Our results thus suggest that TLX not only acts as a repressor of cell cycle and glial differentiation but also activates neuronal lineage commitment in AHPs.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Hipocampo/crecimiento & desarrollo , Neurogénesis/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Represoras/metabolismo , Activación Transcripcional , Adenoviridae , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/análisis , Linaje de la Célula/genética , Células Cultivadas , Proteínas de Dominio Doblecortina , Proteína Doblecortina , Factores de Crecimiento de Fibroblastos/metabolismo , Factores de Crecimiento de Fibroblastos/farmacología , Histona Desacetilasas/análisis , Humanos , Proteínas Asociadas a Microtúbulos/análisis , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/fisiología , Neuropéptidos/análisis , Regiones Promotoras Genéticas , Ratas , Receptores Citoplasmáticos y Nucleares/genética , Proteínas Represoras/genética , Factor de Transcripción Sp1/análisis , Factor de Transcripción Sp1/metabolismo , Tubulina (Proteína)/análisisRESUMEN
AIMS: To investigate the precise mechanisms underlying the action of estrogenic endocrine disruptors, we evaluated the direct effects of synthetic estrogen diethylstilbestrol (DES) on steroidogenesis in Leydig cells, with particular emphasis on the expression of the cholesterol side-chain cleavage enzyme P450scc. Furthermore, the mechanism underlying the action of DES was compared with that of endogenous estrogen 17beta-estradiol (E2), which has a potency equivalent to that of DES. MAIN METHODS: TTE1 Leydig cells were treated with 5 x 10(-)(8) microM to 5 microM DES or E2 for 24h, and P450scc gene expression and the histone modifications underlying their transcriptional activation were examined using reverse transcription-polymerase chain reaction (RT-PCR) and chromatin immunoprecipitation (ChIP), respectively. KEY FINDINGS: P450scc mRNA expression in the DES-treated and E2-treated cells reduced in inverse proportion to the dose of DES and E2, respectively; however, cAMP stimulation induced a recovery in the expression to a level approximately equal to those in the controls. In the DES-treated cells, ChIP assay revealed histone deacetylation in the P450scc promoter region. Interestingly, E2 did not cause histone deacetylation. SIGNIFICANCE: In the early stages of steroidogenesis, DES and E2 directly induced a reduction in P450scc mRNA expression in inverse proportion to their doses, and treatment with cAMP restored the decreased P450scc mRNA expression. Furthermore, DES can induce alterations in the histone modification of the P450scc gene, and natural estrogen and synthetic estrogenic compounds such as DES may induce reproductive disorders through different molecular mechanisms.
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Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Dietilestilbestrol/toxicidad , Disruptores Endocrinos/toxicidad , Expresión Génica/efectos de los fármacos , Células Intersticiales del Testículo/efectos de los fármacos , Acetilación , Andrógenos/biosíntesis , Animales , Línea Celular , Inmunoprecipitación de Cromatina , Estradiol/farmacología , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Regiones Promotoras Genéticas , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
XY females are rare individuals who carry a Y chromosome but are phenotypically female. In approximately 80-90% of these cases, there are no mutations in the SRY gene, a testis-determining gene on the short arm of the Y chromosome, and the pathophysiology of XY females without SRY mutation remains unclear. In the present study, we used a molecular data mining technique to analyze the pathophysiology of an XY female with functional SRY and pericentric inversion of the Y chromosome, and compared the results with those of a normal male. Interestingly, upregulations of numerous genes included in the development category of the Biological Process ontology, including genes associated with sex determination and organ morphogenesis, were seen in the patient. Additionally, the transforming growth factor-beta (TGF-beta) signaling pathway and Wnt signaling pathway, in which most cell-cell interactions during embryonic development are involved, were altered. Alterations in the expression of numerous genes at the developmental stage, including alterations at both the gene and pathway levels, may persist as a vestige of anomalies of sex differentiation that presumably began in the fetal period. The present study indicates that a data mining technique using bioinformatics contributes to identification of not only genes responsible for birth defects, but also disorders of sex development (DSD)-specific pathways, and that this kind of analysis is an important tool for clarifying the pathophysiology of human idiopathic XY gonadal dysgenesis. Our findings could serve as one of the basic datasets which will be used for future follow-up investigations.
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Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Adolescente , Cromosomas Humanos Y , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Redes y Vías Metabólicas/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Aberraciones Cromosómicas Sexuales , Proteína de la Región Y Determinante del Sexo/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación hacia ArribaRESUMEN
In normal ontogenetic development, the expression of the sex-determining region of the Y chromosome (SRY) gene, involved in the first step of male sex differentiation, is spatiotemporally regulated in an elaborate fashion. SRY is expressed in germ cells and Sertoli cells in adult testes. However, only few reports have focused on the expressions of SRY and the other sex-determining genes in both the classical organ developing through these genes (gonad) and the peripheral tissue (skin) of adult XY females. In this study, we examined the gonadal tissue and fibroblasts of a 17-year-old woman suspected of having disorders of sexual differentiation by cytogenetic, histological, and molecular analyses. The patient was found to have the 46,X,inv(Y)(p11.2q11.2) karyotype and streak gonads with abnormally prolonged SRY expression. The sex-determining gene expressions in the patient-derived fibroblasts were significantly changed relative to those from a normal male. Further, the acetylated histone H3 levels in the SRY region were significantly high relative to those of the normal male. As SRY is epistatic in the sex-determination pathway, the prolonged SRY expression possibly induced a destabilizing effect on the expressions of the downstream sex-determining genes. Collectively, alterations in the sex-determining gene expressions persisted in association with disorders of sexual differentiation not only in the streak gonads but also in the skin of the patient. The findings suggest that correct regulation of SRY expression is crucial for normal male sex differentiation, even if SRY is translated normally.
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Inversión Cromosómica/genética , Cromosomas Humanos Y/genética , Epigénesis Genética , Disgenesia Gonadal 46 XY/genética , Aberraciones Cromosómicas Sexuales , Diferenciación Sexual/genética , Proteína de la Región Y Determinante del Sexo/genética , Adolescente , Aberraciones Cromosómicas , Femenino , Perfilación de la Expresión Génica , Genes sry , Humanos , MasculinoRESUMEN
Nerve growth factor (NGF) as an autocrine or paracrine growth factor plays a critical role in the pathogenesis and progression of human pancreatic cancer. NGF is synthesized as a proform (proNGF) that, when cleaved, releases mature ligand (mNGF). proNGF and mNGF bind to high-affinity tyrosine kinase receptor A (TrkA) and low-affinity receptor p75 to different extents. Histamine is a potent stimulator of NGF in the inflammatory lesion as determined by ELISA. This has generally been attributed to the accumulation of mNGF. To determine the effect of histamine on nerve growth factor/receptor expression in human pancreatic cancer, the present study explored intracellular and extracellular NGF production and p75 and TrkA membrane receptor expression in the PANC-1, KMP-6 and PK-1 cell lines. Histamine enhanced NGF secretion and mRNA expression in PANC-1 and KMP-6 cells, but not in PK-1 cells. proNGF was revealed using Western blotting to be the predominant form of NGF, but was significantly reduced by histamine. p75 receptor binding was increased with histamine treatement, but no significant alteration was observed for TrkA. Proliferating cell nuclear antigen (PCNA), an important indicator of cell proliferation, was significantly reduced by histamine stimulation. H1 and H2 receptors were both observed in the pancreatic cancer cells, and the alterations induced by histamine were counteracted by H1 receptor antagonist pyrilamine; however, the H2 receptor subtype was excluded from this process. These results suggest that histamine induces distinct nerve growth factor/receptor responsiveness via H1 receptor-induced signaling, thus affecting pancreatic cancer cell proliferation.
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Effects of early postnatal ethanol exposure on brain-derived neurotrophic factor (BDNF) mRNA expression in the rat hippocampus were investigated. Wistar rats were assigned to either ethanol treatment (ET) separation control (SC) or mother-reared control (MRC) groups. Ethanol exposure was achieved by a vapor inhalation method for 3 hours a day between postnatal days (PND) 1015. On PND 16, 20, 30, and 60, the expression of BDNF mRNA in the hippocampus was determined using real-time RT-PCR analysis. There was a significant age-related increase in the BDNF mRNA expression between PND 3060 in MRC animals. The BDNF mRNA expression in ET rats was increased at both PND 16 and 20 and thereafter decreased at PND 60 compared to SC animals. Such age-related fluctuation in the expression of BDNF mRNA differed from that of MRC animals. The exact functional implications, if any, of these ethanol-induced changes in BDNF mRNA expression remain unknown although it can be speculated that they may have an effect on the behaviors known to be influenced by the hippocampal formation.
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Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Depresores del Sistema Nervioso Central/toxicidad , Etanol/toxicidad , Hipocampo/crecimiento & desarrollo , Hipocampo/metabolismo , ARN Mensajero/biosíntesis , Animales , Peso Corporal/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/genética , Depresores del Sistema Nervioso Central/sangre , Etanol/sangre , Femenino , Hipocampo/efectos de los fármacos , Embarazo , ARN Mensajero/genética , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Maternal alcohol ingestion during pregnancy adversely affects the developing fetus, often leading to fetal alcohol syndrome (FAS). One of the most severe consequences of FAS is brain damage that is manifested as cognitive, learning, and behavioral deficits. The hippocampus plays a crucial role in such abilities; it is also known as one of the brain regions most vulnerable to ethanol-induced neurotoxicity. Our recent studies using morphometric techniques have further shown that ethanol neurotoxicity appears to affect the development of the dentate gyrus in a region-specific manner; it was found that early postnatal ethanol exposure causes a transitory deficit in the hilus volume of the dentate gyrus. It is strongly speculated that such structural modifications, even transitory ones, appear to result in developmental abnormalities in the brain circuitry and lead to the learning disabilities observed in FAS children. Based on reports on possible factors deciding ethanol neurotoxicity to the brain, we review developmental neurotoxicity to the dentate gyrus of the hippocampal formation.
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Giro Dentado/anomalías , Giro Dentado/efectos de los fármacos , Etanol/toxicidad , Neurotoxinas/toxicidad , Anomalías Inducidas por Medicamentos/embriología , Anomalías Inducidas por Medicamentos/patología , Animales , Niño , Giro Dentado/embriología , Modelos Animales de Enfermedad , Etanol/administración & dosificación , Etanol/sangre , Femenino , Trastornos del Espectro Alcohólico Fetal/etiología , Trastornos del Espectro Alcohólico Fetal/patología , Edad Gestacional , Humanos , Recién Nacido , Neurotoxinas/administración & dosificación , Neurotoxinas/sangre , EmbarazoRESUMEN
Herein, we show that both exogenously transfected and endogenously activated p53 repress promoter activity and expression of PDGFRB. p53 binds the proximal promoter containing the CCAAT motif as examined by EMSA and chromatin immunoprecipitation. However, gradual induction of p53 in tet-onSAOS2 cells resulted in a transient increase of the PDGFRB-promoter activity and its expression. As binding of p53 to the promoter increased, previously bound p73, DeltaNp73, c-Myc, HDAC1 and HDAC4 were dismissed from the repressed promoter, and p300 was recruited. The transient increase of the promoter activity was therefore induced by the release of the p73, Myc and HDACs, previously shown to act as repressors to this promoter. Along with further increase of p53, p300 was replaced by HDAC1 and HDAC4, resulting in decreased PDGFRB expression. For the repression, acetylation of the C-terminal lysines of p53 is important, and both acetyl-K373p53 and methyl-K370p53 became bound to the promoter. The acetyl-K373p53 was accumulated in the nucleus and colocalized with promyelocytic leukemia protein. Mitomycin treatment of MEF induced similar epigenetic modification of p53 and its binding to the promoter chromatin. Addition of a PDGFR tyrosine-kinase inhibitor to p53-inducing tet-onSAOS2 increased the number of apoptotic cells. These results suggest that p53 represses the PDGFRB promoter, facilitating the p53-induced apoptosis, whereas tumor cells with p53 mutation or a high level of DeltaNp73 or Myc could become refractory to the regulation.
Asunto(s)
Regiones Promotoras Genéticas , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Proteína p53 Supresora de Tumor/fisiología , Apoptosis , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Proteínas de Unión al ADN/fisiología , Histona Desacetilasa 1 , Histona Desacetilasas/fisiología , Humanos , Cinética , Metilación , Mitomicina/farmacología , Proteínas Nucleares/fisiología , Proteínas Proto-Oncogénicas c-myc/fisiología , Proteínas Represoras/fisiología , Proteína Tumoral p73 , Proteínas Supresoras de Tumor/fisiologíaRESUMEN
We report a considerable number of cells in the ventricular and the subventricular zones (SVZ) of newborn mice to stain positive for the PDGF beta-receptor (PDGFRB). Many of them also stained for nestin and/or GFAP but less frequently for the neuroblast marker doublecortin and for the mitotic marker Ki-67. The SVZ of mice with nestin-Cre conditional deletion of PDGFRB expressed the receptor only on blood vessels and was devoid of any morphological abnormality. PDGFRB(-/-) neurospheres showed a higher rate of apoptosis without any significant decrease in proliferation. They demonstrated reduced capacities of migration and neuronal differentiation in response to not only PDGF-BB but also bFGF. Furthermore, the PDGFR kinase inhibitor STI571 blocked the effects of bFGF in control neurosphere cultures. bFGF increased the activity of the PDGFRB promoter as well as the expression and phosphorylation of PDGFRB. These results suggest the presence of the signaling convergence between PDGF and FGF. PDGFRB is needed for survival, and the effects of bFGF in migration and neural differentiation of the cells may be potentiated by induction of PDGFRB.
Asunto(s)
Expresión Génica/fisiología , Ventrículos Laterales/citología , Ventrículos Laterales/crecimiento & desarrollo , Neuronas/fisiología , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Células Madre/metabolismo , Análisis de Varianza , Animales , Animales Recién Nacidos , Benzamidas , Bromodesoxiuridina/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Expresión Génica/efectos de los fármacos , Mesilato de Imatinib , Proteínas de Filamentos Intermediarios/genética , Proteínas de Filamentos Intermediarios/metabolismo , Antígeno Ki-67/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Nestina , Piperazinas/farmacología , Pirimidinas/farmacología , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Transfección/métodosRESUMEN
We aimed to elucidate the mechanism of action of estrogenic endocrine disruptors and the rescue of reproductive function, particularly the responsiveness of testes to eCG and/or activin A (ACT) after establishing reproductive disorders. Newborn male mice (n = 29) were randomly divided into an untreated group and three treatment groups that received diethylstilbestrol (DES; 100 mug per animal) subcutaneously on Postnatal Day 3 to establish reproductive disorders and daily treatment with PBS (controls: DES + PBS), eCG (eCG group: DES + eCG), or eCG + ACT (eCG + ACT group: DES + eCG + ACT) at 6-8 wk of age prior to mating. After treatment, the controls showed diminished Leydig cells in the testes and thin germ cell layers containing pyknotic germ cells and multinucleated cells. In the eCG and eCG + ACT groups, spermatids and Leydig cells increased markedly. The immunoexpression of androgen receptors in the eCG group and steroidogenic acute regulatory (STAR) protein in the eCG and eCG + ACT groups recovered to approximately the levels in the untreated group; plasma LH and testosterone levels also increased relative to those in the controls. In addition, the cell proliferation index, which is estimated from 5-bromo-2'-deoxyuridine immunoexpression in spermatogonia, increased significantly under eCG treatment, and even more with eCG + ACT. However, the numbers of germ and Leydig cells decreased at 12 wk of age. Thus, ACT and eCG help the testes to recover from the dysfunction induced by neonatal DES administration. Furthermore, the permanent male reproductive disorder induced by neonatal exposure to estrogenic agents may be more likely to result from dysfunction of the hypothalamic-pituitary axis than from dysfunction of the lower reproductive organs.