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Abstract Objective This study aimed to investigate the molecular mechanism of miR-150-5p regulating the malignant biological behavior of Human Epidermoid cancer cell (HEp-2) by targeting peptidyl-prolyl cis/trans isomerase NIMA-Interacting-1 (PIN1). Methods Firstly, qRT-PCR and Western blot were adopted to detect the expression levels of miR-150-5p and PIN1 in cancer tissue and paracancerous tissues of patients with LSCC, and those in human bronchial epithelial cells (16 HBE) and HEp-2. Next, the targeted relationship between miR-150-5p and PIN1 was assessed by bioinformatics website and dual-luciferase reporter assay, followed by their correlation analysis. Besides, after interfering with miR-150-5p or PIN1 expression in HEp-2 cells, CCK-8, cell colony formation assay, and transwell assay were utilized to detect the proliferation, viability, and invasion of cells, respectively. Subsequently, the protein levels of MMP-2, MMP-9, and EMT-related proteins in HEp-2 cells were checked by Western blot. Results Expression of miR-150-5p was down-regulated in LSCC tissues and HEp-2 cells. Moreover, miR-150-5p suppressed proliferation and invasion of HEp-2 cells, affected protein expression related to MMP and EMT, thereby inhibiting development of cancer. The expression of PIN1 was significantly increased in cancer tissues and HEp-2 cells, and there was a targeted relationship and negative correlation between miR-150-5p and PIN1 in cancer tissue. However, overexpression of PIN1 could reverse the effect of miR-150-5p on the proliferation and invasion of HEp-2 cells. Conclusion In a nutshell, there is a targeted relationship between PIN1 and miR-150-5p. Besides, miR-150-5p can inhibit the proliferation and invasion of HEp-2 cells by regulating the expression of PIN1. Level of evidence 3.
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OBJECTIVE: This study aimed to investigate the molecular mechanism of miR-150-5p regulating the malignant biological behavior of Human Epidermoid cancer cell (HEp-2) by targeting peptidyl-prolyl cis/trans isomerase NIMA-Interacting-1 (PIN1). METHODS: Firstly, qRT-PCR and Western blot were adopted to detect the expression levels of miR-150-5p and PIN1 in cancer tissue and paracancerous tissues of patients with LSCC, and those in human bronchial epithelial cells (16 HBE) and HEp-2. Next, the targeted relationship between miR-150-5p and PIN1 was assessed by bioinformatics website and dual-luciferase reporter assay, followed by their correlation analysis. Besides, after interfering with miR-150-5p or PIN1 expression in HEp-2 cells, CCK-8, cell colony formation assay, and transwell assay were utilized to detect the proliferation, viability, and invasion of cells, respectively. Subsequently, the protein levels of MMP-2, MMP-9, and EMT-related proteins in HEp-2 cells were checked by Western blot. RESULTS: Expression of miR-150-5p was down-regulated in LSCC tissues and HEp-2 cells. Moreover, miR-150-5p suppressed proliferation and invasion of HEp-2 cells, affected protein expression related to MMP and EMT, thereby inhibiting development of cancer. The expression of PIN1 was significantly increased in cancer tissues and HEp-2 cells, and there was a targeted relationship and negative correlation between miR-150-5p and PIN1 in cancer tissue. However, overexpression of PIN1 could reverse the effect of miR-150-5p on the proliferation and invasion of HEp-2 cells. CONCLUSION: In a nutshell, there is a targeted relationship between PIN1 and miR-150-5p. Besides, miR-150-5p can inhibit the proliferation and invasion of HEp-2 cells by regulating the expression of PIN1.
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Neoplasias Laríngeas , Laringe , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Isomerasa de Peptidilprolil/genética , Isomerasa de Peptidilprolil/metabolismo , Línea Celular Tumoral , Proliferación Celular , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patología , Laringe/patología , Regulación Neoplásica de la Expresión Génica , Peptidilprolil Isomerasa de Interacción con NIMA/genética , Peptidilprolil Isomerasa de Interacción con NIMA/metabolismoRESUMEN
The SARS-CoV-2 virus, the causative agent of COVID-19, is undergoing constant mutation. Here, we utilized an integrative approach combining epidemiology, virus genome sequencing, clinical phenotyping, and experimental validation to locate mutations of clinical importance. We identified 35 recurrent variants, some of which are associated with clinical phenotypes related to severity. One variant, containing a deletion in the Nsp1-coding region (Δ500-532), was found in more than 20% of our sequenced samples and associates with higher RT-PCR cycle thresholds and lower serum IFN-ß levels of infected patients. Deletion variants in this locus were found in 37 countries worldwide, and viruses isolated from clinical samples or engineered by reverse genetics with related deletions in Nsp1 also induce lower IFN-ß responses in infected Calu-3 cells. Taken together, our virologic surveillance characterizes recurrent genetic diversity and identified mutations in Nsp1 of biological and clinical importance, which collectively may aid molecular diagnostics and drug design.
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COVID-19/inmunología , COVID-19/virología , Interferón Tipo I/inmunología , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Proteínas no Estructurales Virales/genética , Células A549 , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Secuencia de Bases , COVID-19/sangre , Línea Celular , Niño , Preescolar , Chlorocebus aethiops , Femenino , Eliminación de Gen , Genómica , Células HEK293 , Humanos , Lactante , Interferón Tipo I/sangre , Interferón beta/sangre , Interferón beta/metabolismo , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Genética Inversa , Células Vero , Proteínas no Estructurales Virales/inmunología , Adulto JovenRESUMEN
The function of enhancer RNAs (eRNAs) in transcriptional regulation remains obscure. By analyzing the genome-wide nascent transcript profiles in breast cancer cells, we identify a special group of eRNAs that are essential for estrogen-induced transcriptional repression. Using eRNAs of TM4SF1 and EFEMP1 as the paradigms, we find that these RNA molecules not only stabilize promoter-enhancer interactions but also recruit liganded estrogen receptor α (ERα) to particular enhancer regions, facilitate the formation of a functional transcriptional complex, and cause gene silencing. Interestingly, ERα is shown to directly bind with eRNAs by its DNA-binding domain. These eRNAs help with the formation of a specific ERα-centered transcriptional complex and promote the association of the histone demethylase KDM2A, which dismisses RNA polymerase II from designated enhancers and suppresses the transcription of target genes. Our work demonstrates a complete mechanism underlying the action of eRNAs in modulating and refining the locus-specific transcriptional program.
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Elementos de Facilitación Genéticos , Receptor alfa de Estrógeno/metabolismo , Estrógenos/metabolismo , ARN/metabolismo , Línea Celular , Regulación hacia Abajo/genética , Receptor alfa de Estrógeno/química , Proteínas F-Box/metabolismo , Humanos , Histona Demetilasas con Dominio de Jumonji/metabolismo , Modelos Biológicos , Sistemas de Lectura Abierta/genética , Unión Proteica , Dominios Proteicos , ARN Polimerasa II/metabolismo , Transcripción GenéticaRESUMEN
Leonurus japonicus (motherwort) has been widely used to treat gynecological disorders, in which estrogen is often dysregulated, for a long time in China and other Asian countries. However, the chemical constituents and mechanisms underlying the activity of this medicinal plant are not fully understood. Seventeen of forty-six tested natural products from L. japonicus showed stimulatory or inhibitory effects on estrogen biosynthesis with different potency in human ovarian granulosa-like KGN cells. Luteolin-7-methylether (XLY29) potently inhibited 17ß-estradiol production (IC50: 5.213 µM) by decreasing the expression of aromatase, the only enzyme in vertebrates that catalyzes the biosynthesis of estrogens, but had no effect on the catalytic activity of aromatase. XLY29 decreased the expression of aromatase promoter I.3/II, and suppressed the phosphorylation of cAMP response element-binding protein. XLY29 potently inhibited phosphorylation of p38 mitogen-activated protein kinase and AKT but had no effect on phosphorylation of extracellular signal-regulated kinase and c-Jun N-terminal kinase. XLY29 also decreased the serum 17ß-estradiol level and disturbed estrous cycle in mice. These results suggest that modulation of estrogen biosynthesis is a novel effect of L. japonicus, and XLY29 warrants further investigation as a new therapeutic means for the treatment of estrogen-related diseases.
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Productos Biológicos/farmacología , Estradiol/metabolismo , Estrógenos/metabolismo , Células de la Granulosa/efectos de los fármacos , Leonurus , Luteolina/farmacología , Fitoquímicos/farmacología , Animales , Aromatasa/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Femenino , Células de la Granulosa/metabolismo , Humanos , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Ratas Sprague-DawleyRESUMEN
Erianin, a component extracted from the traditional Chinese herbal medicine Dendrobium, has shown significant anti-tumour activity in various cancers but not in bladder cancer. In this study, we assessed the effects of Erianin on bladder cancer growth and elucidated the related mechanisms. First, Erianin was synthesized with high yields, and markedly suppressed EJ and T24 cell proliferation. It induced G2/M-phase arrest in vitro. Furthermore, Erianin triggered apoptosis via caspase cascades activation and the mitochondrial-mediated apoptotic pathway. Bim up-regulation and Bcl-2 down-regulation as the symbol of apoptosis which were found to play the dominant role in the effects of Erianin. We further showed that JNK pathway activation is necessary for the Erianin-mediated anti-proliferation and apoptotic response. Finally, Erianin exhibited anti-tumour activity and induced apoptosis in tumour tissue in vivo. Collectively, these results suggest that Erianin induced cell cycle G2/M-phase arrest and apoptosis via the JNK signalling pathway in bladder cancer, indicating the potential usefulness of Erianin for the therapy of bladder cancer.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Bibencilos/farmacología , Proliferación Celular/efectos de los fármacos , Dendrobium , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Mitocondrias/efectos de los fármacos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Animales , Antineoplásicos/aislamiento & purificación , Proteína 11 Similar a Bcl2/genética , Proteína 11 Similar a Bcl2/metabolismo , Bibencilos/aislamiento & purificación , Línea Celular Tumoral , Dendrobium/química , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Ratones Desnudos , Mitocondrias/enzimología , Mitocondrias/patología , Fenol , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Carga Tumoral/efectos de los fármacos , Neoplasias de la Vejiga Urinaria/enzimología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Premnafulvol A (1), a unique diterpenoid featuring a 6/5/7/3-fused tetracyclic carbon skeleton, with three biosynthetically related analogues, premnafulvols B-D (2-4), were isolated from the aerial parts of Premna fulva. Structures of 1-4 were established by a combination of extensive spectroscopic analyses, quantum chemical calculations, and X-ray crystallography. Plausible biosynthetic pathways of 1-4 were proposed. Interestingly, 2 and 3 exhibited opposite effects on estrogen biosynthesis in human ovarian granulosa-like KGN cells by modulating the expression of aromatase.
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Diterpenos/química , Lamiaceae/química , Aromatasa/genética , Vías Biosintéticas , Línea Celular Tumoral , Diterpenos/aislamiento & purificación , Femenino , Regulación de la Expresión Génica , Humanos , Modelos Moleculares , Estructura Molecular , Componentes Aéreos de las Plantas/química , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Epimedium brevicornum Maxim has a long history of use in the treatment of estrogen deficiency-related diseases. However, the chemical constituents and mechanism of action of this medicinal plant are not fully understood. In the present study, we isolated four new isoprenylated flavonoid glycosides, as well as 16 known flavonoids (13 isoprenylated flavonoids), from this plant. The chemical structures of the new flavonoid glycosides were elucidated by extensive spectroscopic analysis. The new compounds 1-4 were potent promoters of estrogen biosynthesis in human ovarian granulosa-like KGN cells. ZW1, an isoprenylated flavonoid analogue and a specific inhibitor of phosphodiesterase 5 (PDE5), was synthesized and used to explore the mechanism of the isoprenylated analogues on estrogen biosynthesis. ZW1 treatment increased estrogen production by upregulation of aromatase mRNA and protein expression. ZW1 increased the phosphorylation of cAMP response element-binding protein (CREB). Further study showed that the inhibition of PDE5 by ZW1 increased estrogen biosynthesis partly through suppression of phosphodiesterase 3 (PDE3). Our results suggested that the isoprenylated flavonoids from E. brevicornum may produce beneficial health effects through the promotion of estrogen biosynthesis. PDE5 warrants further investigation as a new therapeutic target for estrogen biosynthesis in the prevention and treatment of estrogen-deficiency related diseases.
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Epimedium/química , Estrógenos/biosíntesis , Flavonoides/farmacología , Glicósidos/farmacología , Células de la Granulosa/efectos de los fármacos , Inhibidores de Fosfodiesterasa/farmacología , Línea Celular , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Femenino , Flavonoides/química , Glicósidos/química , Células de la Granulosa/metabolismo , Humanos , Inhibidores de Fosfodiesterasa/química , Plantas Medicinales/químicaRESUMEN
Plasiatine (1), isolated from the seeds of Plantago asiatica, is an unprecedented indole analogue linked to a phenylpropanoid moiety via a carbon bond that builds up a novel heteromeric construction with a C19N2 scaffold. Its structure was determined by spectroscopic data and computational evidence. Notably, experimental assay demonstrated that 1 significantly enhanced the activity of the nonreceptor protein tyrosine phosphatase Shp2 in vitro in a concentration-dependent manner with an EC50 value of 0.97 µM, and activated phosphorylation of ERK, a known target of Shp2. Moreover, plasiatine (1) promoted hepatocellular HepG2 cells migration. Molecular docking suggested that plasiatine (1) binds to the catalytic cleft of Shp2. These results identified plasiatine (1) as the first small molecule Shp2 activator, and it warrants further investigation as a novel pharmaceutical tool to study the function of Shp2 in tumorigenesis.
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Productos Biológicos/farmacología , Activadores de Enzimas/farmacología , Indoles/farmacología , Extractos Vegetales/farmacología , Plantago/química , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Productos Biológicos/aislamiento & purificación , Movimiento Celular/efectos de los fármacos , Activadores de Enzimas/aislamiento & purificación , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/fisiología , Humanos , Indoles/aislamiento & purificación , Simulación del Acoplamiento Molecular , Estructura Molecular , Fosforilación , Extractos Vegetales/aislamiento & purificación , Unión Proteica , Procesamiento Proteico-Postraduccional , Semillas/química , Análisis EspectralRESUMEN
Five new iridoid glucoside derivatives (1-5), three new diterpenoids (7, 12, and 15), and 11 known compounds were isolated from the aqueous EtOH extract of Caryopteris glutinosa. Cell-based estrogen biosynthesis assays indicated that caryopteriside C (3) and caryopterisoid B (12) promote the biosynthesis of estrogen E2, with EC50 values of 11.1 and 8.0 µM, respectively, in human ovarian granulosa-like KGN cells via upregulating the expression of aromatase.
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Diterpenos/aislamiento & purificación , Glucósidos Iridoides/aislamiento & purificación , Lamiaceae/química , Aromatasa , Diterpenos/química , Estrógenos/metabolismo , Femenino , Humanos , Glucósidos Iridoides/química , Estructura Molecular , Resonancia Magnética Nuclear BiomolecularRESUMEN
Hypoxic-ischemic brain damage (HIBD), a leading cause of perinatal disability and death, has limited therapeutic options. Stem cell therapy has been demonstrated as a potential novel therapy for neurological disorders. Compared with other types of stem cells, umbilical cord blood mesenchymal stem cells (UCB-MSCs) have several unique characteristics, such as a higher rate of cell proliferation and clonality. However, the limited life span of UCB-MSCs hinders their clinical application. Therefore, efforts are urgently needed to circumvent this disadvantage. Telomerase reverse transcriptase (TERT), which promotes cell proliferation and survival, plays a protective role in hypoxic-ischemic (HI) brain injury. Thus, it is reasonable to propose that UCB-MSCs modified by exogenous TERT expression might have a longer lifespan and increased viability. Moreover, brain-derived neurotrophic factor (BDNF), a neurotrophin that regulates development, regeneration, survival and maintenance of neurons, facilitates post-injury recovery when administered by infusion or virus-mediated delivery. Therefore, TERT- and BDNF-modified UCB-MSCs may have a longer lifespan and also maintain neural differentiation, thus promoting the recovery of neurological function following hypoxic-ischemic brain damage (HIBD) and thereby representing a new effective strategy for HIBD in neonates.
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Factor Neurotrófico Derivado del Encéfalo/uso terapéutico , Hipoxia-Isquemia Encefálica/terapia , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Telomerasa/uso terapéutico , Animales , Humanos , Recién NacidoRESUMEN
Aromatase is the only enzyme in vertebrates to catalyze the biosynthesis of estrogens. Although inhibitors of aromatase have been developed for the treatment of estrogen-dependent breast cancer, the whole-body inhibition of aromatase causes severe adverse effects. Thus, tissue-selective aromatase inhibitors are important for the treatment of estrogen-dependent cancers. In this study, 63 natural products with diverse structures were examined for their effects on estrogen biosynthesis in human ovarian granulosa-like KGN cells. Two compounds-trans-phytol (SA-20) and (22E)-ergosta-6,9,22-triene-3ß,5α,8α-triol (SA-48)-were found to potently inhibit estrogen biosynthesis (IC50: 1µM and 0.5µM, respectively). Both compounds decreased aromatase mRNA and protein expression levels in KGN cells, but had no effect on the aromatase catalytic activity in aromatase-overexpressing HEK293A cells and recombinant expressed aromatase. The two compounds decreased the expression of aromatase promoter I.3/II. Neither compound affected intracellular cyclic AMP (cAMP) levels, but they inhibited the phosphorylation or protein expression of cAMP response element-binding protein (CREB). The effects of these two compounds on extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (MAPKs), and AKT/phosphoinositide 3-kinase (PI3K) pathway were examined. Inhibition of p38 MAPK could be the mechanism underpinning the actions of these compounds. Our results suggests that natural products structurally similar to SA-20 and SA-48 may be a new source of tissue-selective aromatase modulators, and that p38 MAPK is important in the basal control of aromatase in ovarian granulosa cells. SA-20 and SA-48 warrant further investigation as new pharmaceutical tools for the prevention and treatment of estrogen-dependent cancers.
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Inhibidores de la Aromatasa/farmacología , Aromatasa/metabolismo , Productos Biológicos/farmacología , Diterpenos/farmacología , Estrógenos/biosíntesis , Células de la Granulosa/metabolismo , Ovario/metabolismo , Poaceae/química , Western Blotting , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colesterol/análogos & derivados , Colesterol/farmacología , AMP Cíclico/metabolismo , Antagonistas de Estrógenos/farmacología , Femenino , Células de la Granulosa/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Medicina Tradicional China , Ovario/efectos de los fármacos , Proteínas Quinasas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Recombinantes/metabolismo , Transducción de Señal/efectos de los fármacos , TransfecciónRESUMEN
Broussonetia papyrifera leaves (BPL) as a traditional Chinese medicine are also used in livestock feed for stimulating reproduction, adipose tissue and muscle development; however, the mechanism of their action is still unknown. Through estrogen biosynthesis-guided fractionation in human ovarian granulosa-like KGN cells, five new phenolic glycosides, broussoside A-E(1-5), along with fifteen known dietary phenolic compounds, were isolated from the n-butanol extract of BPL, and their structures were elucidated on the basis of NMR spectra analysis and chemical evidence. New compounds 3, 4, 5 and the known compounds 9 and 10 were found to potently inhibit estrogen biosynthesis in KGN cells. In addition, compounds 9, 17, 18, and 20 showed strong antioxidant activity against ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and DPPH (1, 1'-diphenyl -2-picryl-hydrazyl radical) assays. These findings suggest that BPL may improve meat quality through the regulation of estrogen biosynthesis. Furthermore, they may be useful for the discovery of potential aromatase modulators from natural products. Finally, they could be considered as a new source for natural antioxidants.
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Antioxidantes/farmacología , Vías Biosintéticas/efectos de los fármacos , Broussonetia/química , Estrógenos/metabolismo , Fenoles/farmacología , Extractos Vegetales/farmacología , Hojas de la Planta/química , Antioxidantes/química , Femenino , Depuradores de Radicales Libres , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Humanos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Fenoles/química , Extractos Vegetales/químicaRESUMEN
Differentiation of adipocytes from preadipocytes contributes to adipose tissue expansion in obesity. Impaired adipogenesis may underlie the development of metabolic diseases such as insulin resistance and type 2 diabetes. Mechanistically, a well defined transcriptional network coordinates adipocyte differentiation. The family of paired-related homeobox transcription factors, which includes Prrx1a, Prrx1b, and Prrx2, is implicated with regulation of mesenchymal cell fate, including myogenesis and skeletogenesis; however, whether these proteins impact adipogenesis remains to be addressed. In this study, we identify Prrx1a and Prrx1b as negative regulators of adipogenesis. We show that Prrx1a and Prrx1b are down-regulated during adipogenesis in vitro and in vivo. Stable knockdown of Prrx1a/b enhances adipogenesis, with increased expression of peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding protein-α and FABP4 and increased secretion of the adipokines adiponectin and chemerin. Although stable low-level expression of Prrx1a, Prrx1b, or Prrx2 does not affect 3T3-L1 adipogenesis, transient overexpression of Prrx1a or Prrx1b inhibits peroxisome proliferator-activated receptor-γ activity. Prrx1 knockdown decreases expression of Tgfb2 and Tgfb3, and inhibition of TGFß signaling during adipogenesis mimics the effects of Prrx1 knockdown. These data support the hypothesis that endogenous Prrx1 restrains adipogenesis by regulating expression of TGFß ligands and thereby activating TGFß signaling. Finally, we find that expression of Prrx1a or Prrx1b in adipose tissue increases during obesity and strongly correlates with Tgfb3 expression in BL6 mice. These observations suggest that increased Prrx1 expression may promote TGFß activity in adipose tissue and thereby contribute to aberrant adipocyte function during obesity.
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Adipogénesis , Proteínas de Homeodominio/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipogénesis/efectos de los fármacos , Adipogénesis/genética , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Técnicas de Silenciamiento del Gen , Proteínas de Homeodominio/genética , Humanos , Ligandos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , PPAR gamma/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Especificidad de la Especie , Factores de Transcripción/genética , Factor de Crecimiento Transformador beta3/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proteína Wnt3A/metabolismoRESUMEN
Wnt10b is an established regulator of mesenchymal stem cell (MSC) fate that inhibits adipogenesis and stimulates osteoblastogenesis, thereby impacting bone mass in vivo. However, downstream mechanisms through which Wnt10b exerts these effects are poorly understood. Moreover, whether other endogenous Wnt ligands also modulate MSC fate remains to be fully addressed. In this study, we identify Wnt6 and Wnt10a as additional Wnt family members that, like Wnt10b, are downregulated during development of white adipocytes in vivo and in vitro, suggesting that Wnt6 and/or Wnt10a may also inhibit adipogenesis. To assess the relative activities of Wnt6, Wnt10a and Wnt10b to regulate mesenchymal cell fate, we used gain- and loss-of function approaches in bipotential ST2 cells and in 3T3-L1 preadipocytes. Enforced expression of Wnt10a stabilizes ß-catenin, suppresses adipogenesis and stimulates osteoblastogenesis to a similar extent as Wnt10b, whereas stable expression of Wnt6 has a weaker effect on these processes than Wnt10a or Wnt10b. In contrast, knockdown of endogenous Wnt6 is associated with greater preadipocyte differentiation and impaired osteoblastogenesis than knockdown of Wnt10a or Wnt10b, suggesting that, among these Wnt ligands, Wnt6 is the most potent endogenous regulator of MSC fate. Finally, we show that knockdown of ß-catenin completely prevents the inhibition of adipogenesis and stimulation of osteoblast differentiation by Wnt6, Wnt10a or Wnt10b. Potential mechanisms whereby Wnts regulate fate of MSCs downstream of ß-catenin are also investigated. In conclusion, this study identifies Wnt10a and Wnt6 as additional regulators of MSC fate and demonstrates that mechanisms downstream of ß-catenin are required for Wnt6, Wnt10a and Wnt10b to influence differentiation of mesenchymal precursors.
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Adipogénesis , Proteínas del Tejido Nervioso/metabolismo , Osteoblastos/metabolismo , Osteogénesis , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Células 3T3-L1 , Animales , Linaje de la Célula , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Osteoblastos/citología , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Transducción de SeñalRESUMEN
Total RNA was isolated from kidney of BaMei pig, a local strain of Chinese pig, and then the cDNA sequence of SOCS-2 gene was cloned by RT-PCR (GenBank accepted number is EF121242). Then the cloned SOCS-2 gene was inserted into PMD19-T vector by T/A cloning, transformed into DH-5alpha, tested by PCR and sequenced. The data show that the homology of the cloned porcine SOCS-2, including 822 bp, is more than 93% and that of the deduced amino acid sequence is 89% when compared with human, rat and mice. And the molecular weight of SOCS-2 protein is about 22.25 kD and PI is 8.03. The cloning of SOCS-2 gene is useful for the further research on the molecular mechanism by which regulating growth and development of organism.