RESUMEN
OBJECTIVE: Expansion of adipose tissue during obesity through the recruitment of newly generated adipocytes (hyperplasia) is metabolically healthy, whereas that through the enlargement of pre-existing adipocytes (hypertrophy) leads to metabolic complications. Accumulating evidence from genetic fate mapping studies suggests that in animal models receiving a high-fat diet (HFD), only adipocyte progenitors (APs) in gonadal white adipose tissue (gWAT) have proliferative potential. However, the proliferative potential and differentiating capacity of APs in the inguinal WAT (iWAT) of male mice remains controversial. The objective of this study was to investigate the proliferative and adipogenic potential of APs in the iWAT of HFD-fed male mice. METHODS: We generated PDGFRα-GFP-Cre-ERT2/tdTomato (KI/td) mice and traced PDGFRα-positive APs in male mice fed HFD for 8 weeks. We performed a comprehensive phenotypic analysis, including the histology, immunohistochemistry, flow cytometry, and gene expression analysis, of KI/td mice fed HFD. RESULTS: Contrary to the findings of others, we found an increased number of newly generated tdTomato+ adipocytes in the iWAT of male mice, which was smaller than that observed in the gWAT. We found that in male mice, the iWAT has more proliferating tdTomato+ APs than the gWAT. We also found that tdTomato+ APs showed a higher expression of Dpp4 and Pi16 than tdTomato- APs, and the expression of these genes was significantly higher in the iWAT than in the gWAT of mice fed HFD for 8 weeks. Collectively, our results reveal that HFD feeding induces the proliferation of tdTomato+ APs in the iWAT of male mice. CONCLUSION: In male mice, compared with gWAT, iWAT undergoes hyperplasia in response to 8 weeks of HFD feeding through the recruitment of newly generated adipocytes due to an abundance of APs with a high potential for proliferation and differentiation.
Asunto(s)
Adipocitos/metabolismo , Dieta Alta en Grasa/efectos adversos , Adipogénesis , Animales , Femenino , Masculino , Ratones , Ratones Congénicos , Ratones TransgénicosRESUMEN
We identified two genes, Cebelin and Cebelin-like, encoding unknown proteins in mice. Cebelin and Cebelin-like consist of 168 and 167 amino acids with putative secreted signal sequences. However, Cebelin and Cebelin-like are cellular proteins not secreted proteins. Cebelin and Cebelin-like were predominantly expressed in the brain among major tissues examined. The expression of Cebelin in the brain was predominantly detected in the internal granule layer of the cerebellum.
RESUMEN
Mesenchymal stem cells (MSCs) are somatic stem cells that can be derived from adult bone marrow (BM) and white adipose tissue (WAT), and that display multipotency and self-renewal capacity. Although MSCs are essential for tissue formation and have already been used in clinical therapy, the origins and markers of these cells remain unknown. In this study, we first investigated the developmental process of MSCs in mouse embryos using the gene encoding platelet-derived growth factor receptor α (Pdgfra) as a marker. We then traced cells expressing Pdgfra and other genes (brachyury, Sox1 and Pmx1) in various mutant mouse embryos until the adult stage. This tracing of MSC origins and destinies indicates that embryonic MSCs emerge in waves and that almost all adult BM MSCs and WAT MSCs originate from mesoderm and embryonic Pdgfrα-positive cells. Furthermore, we demonstrate that adult Pdgfrα-positive cells are involved in some pathological conditions.
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Tejido Adiposo Blanco/citología , Tejido Adiposo Blanco/metabolismo , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Tejido Adiposo Blanco/crecimiento & desarrollo , Animales , Biomarcadores/metabolismo , Diferenciación Celular , Linaje de la Célula , Femenino , Proteínas Fetales/genética , Proteínas Fetales/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Embarazo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismoRESUMEN
Human induced pluripotent stem (hiPS) cells are very attractive tools for modeling diseases and regenerative medicine. However, to achieve them, the efficient differentiation methods of hiPS cells into aimed cell type in vitro are necessary. Because mesoderm cells are useful in particular, we have developed the differentiation of mouse embryonic stem (mES) cells into mesoderm cells previously. In this time, these methods were improved for hiPS cells and now human mesoderm cells are able to be obtained efficiently. It is certain that the new methods are applicable to various studies and therapies.
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Técnicas de Cultivo de Célula/métodos , Técnicas de Reprogramación Celular/métodos , Reprogramación Celular , Células Madre Pluripotentes Inducidas/citología , Mesodermo/citología , Animales , Antígenos de Diferenciación/análisis , Diferenciación Celular , Linaje de la Célula , Condrogénesis , Ensayo de Unidades Formadoras de Colonias , Medios de Cultivo/farmacología , Fibroblastos/citología , Humanos , Mesodermo/química , Ratones , Osteogénesis , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/análisis , Receptor 2 de Factores de Crecimiento Endotelial Vascular/análisisRESUMEN
Platelet-derived growth factor (PDGF) and its receptor play an important role in embryogenesis. PDGF receptor α (PDGFRα) is expressed specifically in the embryonic day 7.5 (E7.5) mesoderm and in the E9.5 neural crest among other tissues. PDGFRα-expressing cells and their descendants are involved in the formation of various tissues. To trace PDGFRα-expressing cells in vivo, we generated a knock-in mouse line that expressed a fusion protein of green fluorescent protein (GFP), Cre recombinase (Cre), and mutated estrogen receptor ligand-binding domain (ERT2) under the control of the PDGFRα promoter. In these mice, Cre activity in PDGFRα-expressing cells could be induced by tamoxifen treatment. Taken together, our results suggest that the knock-in mouse line generated here could be useful for studying PDGFRα-expressing cells and their descendants in vivo at various stages of development.
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Proteínas Fluorescentes Verdes/genética , Integrasas/genética , Dominios y Motivos de Interacción de Proteínas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptores de Estrógenos/genética , Animales , Técnica del Anticuerpo Fluorescente , Expresión Génica , Técnicas de Sustitución del Gen , Orden Génico , Marcación de Gen , Genes Reporteros , Sitios Genéticos , Proteínas Fluorescentes Verdes/metabolismo , Ratones , Ratones Transgénicos , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptores de Estrógenos/química , TransgenesRESUMEN
We identified a gene encoding a novel secreted protein in mice, humans, and zebrafish. As the protein of 222 amino acids is similar to Brorin, a secreted BMP antagonist, which is a member of the Chordin family, we named it Brorin-like. Recombinant Brorin-like protein weakly but significantly inhibited the activity of BMP in mouse preosteoblastic cells and promoted neurogenesis in mouse neural precursor cells. Brorin-like was predominantly expressed in the adult brain and embryonic neural tissues. The inhibition of Brorin-like functions in zebrafish resulted in the impairment of neural development. Brorin-like potentially plays roles in neural development and functions.
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Proteínas Morfogenéticas Óseas/metabolismo , Glicoproteínas/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Proteínas del Tejido Nervioso/genética , Neuronas/metabolismo , Proteínas de Pez Cebra/genética , Células 3T3 , Secuencia de Aminoácidos , Animales , Astrocitos/citología , Astrocitos/metabolismo , Proteínas Morfogenéticas Óseas/antagonistas & inhibidores , Células COS , Diferenciación Celular/genética , Células Cultivadas , Chlorocebus aethiops , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Glicoproteínas/metabolismo , Glicoproteínas/farmacología , Humanos , Hibridación in Situ , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/farmacología , Ratones , Datos de Secuencia Molecular , Neuronas/citología , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Transducción de Señal/efectos de los fármacos , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/metabolismoRESUMEN
A gene encoding a novel secreted protein in mice and humans was identified, and named Neucrin. Mouse Neucrin consists of 343 amino acids with a cysteine-rich domain in its carboxyl terminal region. The positions of 10 cysteine residues in the cysteine-rich domain are similar to those of Dickkopfs (Dkks), secreted Wnt antagonists. However, whereas Dkks have two cysteine-rich domains, Neucrin has only one. Neucrin as well as Dkks bound to LDL receptor-related protein 6 and inhibited the stabilization of cytosolic beta-catenin, indicating that Neucrin is an antagonist of canonical Wnt signaling. Mouse Neucrin expression was not detected in any major tissues in the adult, but was detected in developing neural tissues, including the brain and spinal cord. The expression pattern of Neucrin is distinct from that of any Dkk. Neucrin is a unique secreted Wnt antagonist that is predominantly expressed in developing neural tissues.
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Encéfalo/embriología , Encéfalo/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Wnt/antagonistas & inhibidores , Secuencia de Aminoácidos , Animales , Cisteína/química , Cisteína/metabolismo , Embrión de Mamíferos/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/química , Péptidos y Proteínas de Señalización Intercelular/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad , Ratones , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/genética , Estabilidad Proteica , Estructura Terciaria de Proteína , Receptores de LDL/metabolismo , beta Catenina/metabolismoRESUMEN
Fgf receptor 2c (Fgfr2c) was expressed in mature adipocytes of mouse white adipose tissue (WAT). To examine the role of Fgfr2c in mature adipocytes, we generated adipocyte-specific Fgfr2 knockout (Fgfr2 CKO) mice. The hypertrophy impairment of adipocytes in the mesenteric WAT but not in the subcutaneous WAT and decreased plasma free fatty acid (FFA) levels were observed in Fgfr2 CKO mice. Although the expression of genes involved in adipocyte differentiation and lipid metabolism in the mesenteric WAT was essentially unchanged, the expression of uncoupling protein 2 potentially involved in energy dissipation was significantly increased. Among potential Fgf ligands for Fgfr2c, Fgf9 was preferentially expressed in the mesenteric WAT. The present findings indicate that Fgfr2c potentially activated by Fgf9 plays a role in the adipocyte hypertrophy in the mesenteric WAT and FFA metabolism and/or energy dissipation in the mesenteric WAT might be involved in the hypertrophy impairment.
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Adipocitos/patología , Tejido Adiposo Blanco/patología , Mesenterio/patología , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Animales , Animales Recién Nacidos , Transporte Biológico/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Metabolismo Energético/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Marcación de Gen , Glucosa/metabolismo , Hipertrofia , Metabolismo de los Lípidos/efectos de los fármacos , Mesenterio/efectos de los fármacos , Mesenterio/metabolismo , Ratones , Ratones Noqueados , Tamaño de los Órganos/efectos de los fármacos , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Tamoxifeno/farmacologíaRESUMEN
We identified a gene encoding a novel secreted protein in mice and humans and named it Brorin. Mouse Brorin consists of 324 amino acids with a putative secreted signal sequence at its amino terminus and two cysteine-rich domains in its core region. Positions of 10 cysteine residues in the domains of Brorin are similar to those in the cysteine-rich domains of members of the Chordin family. However, the amino acid sequence of Brorin is not significantly similar to that of any other member of the Chordin family, indicating that Brorin is a unique member of the family. Mouse Brorin protein produced in cultured cells was efficiently secreted into the culture medium. The protein inhibited the activity of bone morphogenetic protein 2 (BMP2) and BMP6 in mouse preosteoblastic MC3T3-E1 cells. Mouse Brorin was predominantly expressed in neural tissues in embryos and also predominantly expressed in the adult brain. In the brain, the expression was detected in neurons, but not glial cells. The neural tissue-specific expression profile of Brorin is quite distinct from that of any other member of the Chordin family. Brorin protein promoted neurogenesis, but not astrogenesis, in mouse neural precursor cells. The present findings indicate that Brorin is a novel secreted BMP antagonist that potentially plays roles in neural development and functions.
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Proteínas Morfogenéticas Óseas/antagonistas & inhibidores , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Organogénesis/fisiología , Células Madre/metabolismo , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Animales , Proteína Morfogenética Ósea 2 , Proteína Morfogenética Ósea 6 , Proteínas Morfogenéticas Óseas/metabolismo , Encéfalo/metabolismo , Línea Celular , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Proteínas de la Matriz Extracelular , Glicoproteínas , Humanos , Péptidos y Proteínas de Señalización Intercelular , Ratones , Proteínas del Tejido Nervioso/genética , Neuronas/citología , Especificidad de Órganos/fisiología , Homología de Secuencia de Aminoácido , Células Madre/citología , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
The development of white adipose tissue (WAT) involves adipogenesis and cell proliferation. Although the adipogenesis has been well studied, the cell proliferation has not. Therefore, we examined the mechanism of the proliferation by analyzing Fgf10(-/-) mouse embryonic WAT, in which adipogenesis and proliferation were severely impaired. D-type cyclin expression and retinoblastoma family protein phosphorylation essential for cell proliferation were examined in WAT. Both cyclin D2 expression and p130 phosphorylation were impaired in the Fgf10(-/-) WAT. In mouse embryonic fibroblasts, Fgf10 stimulated cyclin D2 expression and p130 phosphorylation, which were inhibited by an inhibitor of the Ras/MAPK pathway. These results suggest that Fgf10 stimulates cell proliferation in WAT through the Ras/MAPK pathway followed by the cyclin D2-dependent phosphorylation of p130. In contrast, expression but not phosphorylation of pRb was impaired in the Fgf10(-/-) WAT. As pRb is essential for adipogenesis, Fgf10 might play a role in adipogenesis by inducing its expression.
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Tejido Adiposo/citología , Factor 10 de Crecimiento de Fibroblastos/fisiología , Adipogénesis/fisiología , Tejido Adiposo/metabolismo , Animales , Proliferación Celular , Ciclina D2 , Ciclinas/metabolismo , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Ratones , Fosforilación , Proteína de Retinoblastoma/metabolismo , Proteína p130 Similar a la del Retinoblastoma/metabolismoRESUMEN
Clinical characteristics, diagnostic imaging, arthroscopic findings, and surgical results of arthroscopic treatment are reported in 62 hands with traumatic triangular fibrocartilage complex (TFCC) injury treated between 1995 and 2002. This retrospective study also describes and compares the results of a novel arthroscopic suture technique for repairing tears with Palmer's class 1B and 1D tears. According to Palmer's classification, there were 10 class 1A, 27 1B, 8 1C, and 17 1D injuries. The arthroscopic suture and débridement treatments were done under brachial plexus block as a 1-day in-hospital procedure. Class 1D tears required transradial fixation to anchor the TFCC. Surgical results of suture groups according to Minami's criteria were excellent in 16 hands, good in 15 hands, fair in 1 hand, and poor in 1 hand. The results of the débridement group were excellent in 16 hands, good in 10 hands, fair in 2 hands, and poor in 1 hand. The results of the current study indicate that the novel suture technique were easy to perform, provided strong, tight repair for class 1D injuries, and was applicable for class 1B injuries in this small case series.