RESUMO
Chordin like-1 (CHRDL1) is an antagonist of bone morphogenetic proteins (BMPs) that acts through binding BMPs and blocking their interaction with BMP receptors. CHRDL1 plays a role in osteoblast differentiation but controversial effects were reported. On the other hand, the role of CHRDL1 in adipogenesis is unknown. In the present study, we investigated the function of CHRDL1 in regulating differentiation of osteoblasts and adipocytes and elucidated the underlying mechanism. CHRDL1 expression was downregulated during osteogenesis while it was upregulated during adipogenesis in primary cultured and established mesenchymal progenitor cell lines. Functional experiments revealed that CHRDL1 suppressed osteoblast differentiation and promoted adipocyte differentiation. Mechanistic explorations revealed that CHRDL1 is directly bound to insulin-like growth factor binding protein 3 (IGFBP3) and attenuated the degradation of the latter. Furthermore, CHRDL1 and IGFBP3 suppressed the activity of insulin receptor substrate 1 (IRS1)/AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin kinase complex 1 (mTORC1) signaling in progenitor cells undergoing osteogenic differentiation. By contrast, they activated AKT/mTORC1 signaling independently of IRS1 during adipogenic differentiation. CHRDL1 enhanced the interaction of nuclear IGFBP3 and retinoid X receptor α (RXRα) during adipogenesis, and inhibition of RXR inactivated AKT and attenuated the stimulation of adipogenic differentiation by CHRDL1. Overexpression of IGFBP3 relieved the perturbation of osteogenic and adipogenic differentiation of progenitor cells induced by CHRDL1 silencing. Finally, CHRDL1 and IGFBP3 were upregulated in the trabecular bone of aged mice. Our study provides evidence that CHRDL1 reciprocally regulates osteoblast and adipocyte differentiation through stabilizing IGFBP3 and differentially modulating AKT/mTORC1 signaling.
Assuntos
Osteogênese , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Adipócitos/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/fisiologia , Proteínas do Olho/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Osteoblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
Adipogenesis is a finely controlled process and its dysfunction may contribute to metabolic disorders such as obesity. Metastasis suppressor 1 (MTSS1) is a player in tumorigenesis and metastasis of various types of cancers. To date, it is not known whether and how MTSS1 plays a role in adipocyte differentiation. In the current study, we found that MTSS1 was upregulated during adipogenic differentiation of established mesenchymal cell lines and primary cultured bone marrow stromal cells. Gain-of-function and loss-of-function experiments uncovered that MTSS1 facilitated adipocyte differentiation from mesenchymal progenitor cells. Mechanistic explorations revealed that MTSS1 bound and interacted with FYN, a member of Src family of tyrosine kinases (SFKs), and protein tyrosine phosphatase receptor-δ (PTPRD). We demonstrated that PTPRD was capable of inducing the differentiation of adipocytes. Overexpression of PTPRD attenuated the impaired adipogenesis induced by the siRNA targeting MTSS1. Both MTSS1 and PTPRD activated SFKs by suppressing the phosphorylation of SFKs at Tyr530 and inducing the phosphorylation of FYN at Tyr419. Further investigation showed that MTSS1 and PTPRD were able to activate FYN. Collectively, our study has for the first time unraveled that MTSS1 plays a role in adipocyte differentiation in vitro through interacting with PTPRD and thereby activating SFKs such as FYN tyrosine kinase.
Assuntos
Adipogenia , Proteínas dos Microfilamentos , Proteínas de Neoplasias , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores , Humanos , Diferenciação Celular , Proteínas dos Microfilamentos/genética , Proteínas de Neoplasias/genética , Fosforilação , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/genéticaRESUMO
Adipogenesis is a tightly regulated process, and its dysfunction has been linked to metabolic disorders such as obesity. Forkhead box k1 (Foxk1) is known to play a role in the differentiation of myogenic precursor cells and tumorigenesis of different types of cancers; however, it is not clear whether and how it influences adipocyte differentiation. Here, we found that Foxk1 was induced in mouse primary bone marrow stromal cells (BMSCs) and established mesenchymal progenitor/stromal cell lines C3H/10T1/2 and ST2 after adipogenic treatment. In addition, obese db/db mice have higher Foxk1 expression in inguinal white adipose tissue than nonobese db/m mice. Foxk1 overexpression promoted adipogenic differentiation of C3H/10T1/2, ST2 cells and BMSCs, along with the enhanced expression of CCAAT/enhancer binding protein-α, peroxisome proliferator-activated receptor γ (Pparγ), and fatty acid binding protein 4. Moreover, Foxk1 overexpression enhanced the expression levels of lipogenic factors during adipogenic differentiation in both C3H/10T1/2 cells and BMSCs. Conversely, Foxk1 silencing impaired these cells from fully differentiating. Furthermore, adipogenic stimulation induced the nuclear translocation of Foxk1, which depended on the mTOR and PI3-kinase signaling pathways. Subsequently, Foxk1 is directly bound to the Pparγ2 promoter, stimulating its transcriptional activity and promoting adipocyte differentiation. Collectively, our study provides the first evidence that Foxk1 promotes adipocyte differentiation from progenitor cells by promoting nuclear translocation and upregulating the transcriptional activity of the Pparγ2 promoter during adipogenic differentiation.
Assuntos
Adipogenia , PPAR gama , Camundongos , Animais , Adipogenia/fisiologia , PPAR gama/genética , PPAR gama/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Adipócitos/metabolismo , Camundongos Endogâmicos C3H , Diferenciação Celular , Obesidade/metabolismo , Células 3T3-L1RESUMO
Metastasis suppressor 1 (MTSS1) plays an inhibitory role in tumorigenesis and metastasis of a variety of cancers. To date, the function of MTSS1 in the differentiation of marrow stromal progenitor cells remains to be explored. In the current study, we investigated whether and how MTSS1 has a role in osteoblast differentiation and bone homeostasis. Our data showed that MTSS1 mRNA was upregulated during osteoblast differentiation and downregulated in the osteoblastic lineage cells of ovariectomized and aged mice. Functional studies revealed that MTSS1 promoted the osteogenic differentiation from marrow stromal progenitor cells. Mechanistic explorations uncovered that the inactivation of Src and afterward activation of canonical Wnt signaling were involved in osteoblast differentiation induced by MTSS1. The enhanced osteogenic differentiation induced by MTSS1 overexpression was attenuated when Src was simultaneously overexpressed, and conversely, the inhibition of osteogenic differentiation by MTSS1 siRNA was rescued when the Src inhibitor was supplemented to the culture. Finally, the in vivo transfection of MTSS1 siRNA to the marrow of mice significantly reduced the trabecular bone mass, along with the reduction of trabecular osteoblasts, the accumulation of marrow adipocytes, and the increase of phospho-Src-positive cells on the trabeculae. No change in the number of osteoclasts was observed. This study has unraveled that MTSS1 contributes to osteoblast differentiation and bone homeostasis through regulating Src-Wnt/ß-catenin signaling. It also suggests the potential of MTSS1 as a new target for the treatment of osteoporosis.
Assuntos
Osso e Ossos/metabolismo , Diferenciação Celular/genética , Proteínas dos Microfilamentos/genética , Proteínas de Neoplasias/genética , Osteoblastos/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/genética , Quinases da Família src/genética , Animais , Western Blotting , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Homeostase/genética , Humanos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Osteoblastos/citologia , Osteogênese/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta Catenina/metabolismo , Quinases da Família src/metabolismoRESUMO
We here investigated molecular basis of notch receptor GLP-1 in controlling simulated microgravity stress in Caenorhabditis elegans. glp-1 expression was decreased by simulated microgravity. Meanwhile, glp-1 mutation caused resistance to toxicity of simulated microgravity. GLP-1 acted in germline cells to control toxicity of simulated microgravity. In germline cells, RNAi knockdown of glp-1 increased daf-16 expression. RNAi knockdown of daf-16 suppressed resistance to toxicity of simulated microgravity in glp-1 mutant. In simulated microgravity treated worms, germline RNAi knockdown of glp-1 decreased expressions of daf-28, ins-39, and ins-8 encoding insulin peptides, and resistance to simulated microgravity toxicity could be detected in daf-28(RNAi), ins-39(RNAi), and ins-8(RNAi) worms. In simulated microgravity treated worms, RNAi knockdown of daf-28, ins-39, or ins-8 in germline cells further increased expression and nucleus localization of transcriptional factor DAF-16 in intestinal cells. Therefore, the GLP-1-activated germline-intestine communication of insulin signaling is required for control of simulated microgravity toxicity in C. elegans.
Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/metabolismo , Insulina/fisiologia , Receptores Notch/fisiologia , Simulação de Ausência de Peso , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Células Germinativas/metabolismo , Intestinos , Especificidade de Órgãos , Interferência de RNA , Receptores Notch/antagonistas & inibidores , Receptores Notch/genética , Transdução de Sinais , Estresse FisiológicoRESUMO
Recent evidence revealed that lysophosphatidic acid receptor 4 (LPAR4) plays a role in osteogenesis and bone remodeling in mice. However, the molecular mechanism by which LPAR4 controls osteogenic and adipogenic differentiation of mesenchymal progenitor cells remains pending. In the current study, our data showed that Lpar4 was expressed in bone and adipose tissue and the expression increased during osteoblast and adipocyte differentiation. Lpar4 overexpression in stromal ST2 and preosteoblastic MC3T3-E1 cells inhibited osteogenic differentiation. By contrast, Lpar4 overexpression in ST2 and mesenchymal C3H10T1/2 cells enhanced adipogenic differentiation. Conversely, depletion of endogenous Lpar4 in the progenitor cells induced osteogenic differentiation and inhibited adipogenic differentiation. Furthermore, enhanced osteoblast differentiation and alleviated fat accumulation were observed in marrow of mice after in vivo transfection of Lpar4 siRNA. Mechanism investigations revealed that LPAR4 inhibited the activation of ras homolog family member A (RhoA)/Rho-associated kinases 1 (ROCK1) and canonical Wnt signal pathways. ROCK1 was shown to be able to activate Wnt/ß-catenin pathway. We further demonstrated that the overexpression of ROCK1 stimulated osteogenic differentiation and restrained adipogenic differentiation from stromal progenitor cells. Moreover, overexpression of ROCK1 attenuated the inhibition of osteogenic differentiation by LPAR4. The current study has provided evidences demonstrating that RhoA/ROCK1 activates ß-catenin signaling to promote osteogenic differentiation and conversely restrain adipogenic differentiation. The inactivation of RhoA/ROCK1/ß-catenin signaling is involved in LPAR4 regulation of the directional differentiation of marrow stromal progenitor cells.
Assuntos
Receptores de Ácidos Lisofosfatídicos/metabolismo , Células-Tronco/metabolismo , beta Catenina/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Diferenciação Celular , CamundongosRESUMO
To evaluate the clinical outcome of deep hypothermic preservation of autologous skin in the treatment of large-area skin avulsion. Medium or full thickness-skin slices were harvested from large avulsion flaps between July and November 2017. They were stored in liquid nitrogen by vitrification. After the patient's condition became stable and the growth of the wound granulation tissue was satisfactory, the frozen skin slices were reheated quickly and replanted to the wound. Autologous skin that had been kept by deep cryopreservation had a high survival rate when grafted. It did not create new trauma or bring additional pain to patients. Yet it could shorten the course of treatment and reduce the medical cost for patients. It is an effective and economical way to treat large-area skin avulsion.
Assuntos
Avulsões Cutâneas/terapia , Transplante de Pele , Temperatura , Adulto , Avulsões Cutâneas/patologia , Feminino , Seguimentos , Tecido de Granulação/patologia , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Pele/patologia , Transplante AutólogoRESUMO
Due to their excellent catalytic activities, cerium oxide nanoparticles have promise as biological nanoenzymes. A redox reaction occurs between Ce3+ ions and Ce4+ ions during which they undergo conversion by acquiring or losing electrons as well as forming oxygen vacancies (or defects) in the lattice structure, which can act as antioxidant enzymes and simulate various enzyme activities. A number of cerium oxide nanoparticles have been engineered with multienzyme activities, including catalase, superoxide oxidase, peroxidase, and oxidase mimetic properties. Cerium oxide nanoparticles have nitric oxide radical clearing and radical scavenging properties and have been widely used in a number of fields of biology, including biomedicine, disease diagnosis, and treatment. This review provides a comprehensive introduction to the catalytic mechanisms and multiple enzyme activities of cerium oxide nanoparticles, along with their potential applications in the treatment of diseases of the brain, bones, nerves, and blood vessels.
RESUMO
Snakes are sometimes regarded as pets and are used in traditional Chinese medicine. Cryptosporidium spp. are frequently identified in snakes, representing an important pathogen and causing gastrointestinal diseases. Current data indicate that risk factors for infection and patterns of clinical symptom presentation may differ among Cryptosporidium spp. To better understand the infection status by Cryptosporidium spp., fecal samples were collected from 603 asymptomatic and 147 symptomatic snakes in 26 provinces of China. These samples came from Elaphe guttata, Elaphe obsoleta, Pituophis melanoleucus, Thamnophis sirtalis, Lampropeltis getulus, and Heterodon nasicus. The partial small subunit (SSU) rRNA gene was amplified using nested polymerase chain reaction (PCR) to investigate the infection rate of Cryptosporidium spp., and to assess evolutionary relationships and genetic characterization. A prevalence of 20% was recorded in asymptomatic snakes, with age identified as a significant risk factor. In contrast, 70% of symptomatic snakes were positive for Cryptosporidium spp., with Cryptosporidium serpentis and Cryptosporidium varanii (syn. C. saurophilum). Further analysis revealed a potential association between C. serpentis and regurgitation, and C. varanii and diarrhea, while neither species was linked to flatulence. To our knowledge, this is the first study to report Cryptosporidium spp. and associated clinical signs in symptomatic snakes in China. This study aims to enhance the understanding of Cryptosporidium infections, risk factors, and clinical manifestations in snakes, providing data crucial for the control and prevention of cryptosporidiosis.
Title: Cryptosporidium spp. chez les serpents captifs de 26 provinces de Chine : prévalence, caractérisation moléculaire et symptômes. Abstract: Les serpents sont parfois considérés comme animaux de compagnie et sont utilisés en médecine traditionnelle chinoise. Des Cryptosporidium spp. sont fréquemment identifiés chez les serpents, ont un rôle d'agent pathogène important et provoquent des maladies gastro-intestinales. Les données actuelles indiquent que les facteurs de risque d'infection et les schémas de présentation des symptômes cliniques peuvent varier en fonction des espèces de Cryptosporidium. Pour mieux comprendre l'état d'infection par Cryptosporidium spp., des échantillons fécaux ont été collectés auprès de 603 serpents asymptomatiques et 147 serpents symptomatiques dans 26 provinces de Chine. Ces échantillons provenaient d'Elaphe guttata, Elaphe obsoleta, Pituophis melanoleucus, Thamnophis sirtalis, Lampropeltis getulus et Heterodon nasicus. Le gène de l'ARNr de la petite sous-unité partielle (SSU) a été amplifié à l'aide d'une réaction en chaîne par polymérase (PCR) imbriquée pour étudier le taux d'infection par Cryptosporidium spp. et évaluer les relations évolutives et la caractérisation génétique. Une prévalence de 20 % a été trouvée chez les serpents asymptomatiques, l'âge étant identifié comme un facteur de risque important. En revanche, 70 % des serpents symptomatiques étaient positifs à Cryptosporidium spp. avec Cryptosporidium serpentis et Cryptosporidium varanii (syn. C. saurophilum). Une analyse plus approfondie a révélé une association potentielle entre C. serpentis et la régurgitation, et C. varanii et la diarrhée, alors qu'aucune des deux espèces n'était liée aux flatulences. À notre connaissance, il s'agit ici de la première étude à signaler la présence de Cryptosporidium spp. et les signes cliniques associés chez des serpents symptomatiques en Chine. Cette étude vise à améliorer la compréhension des infections à Cryptosporidium, des facteurs de risque et des manifestations cliniques chez les serpents, en fournissant des données cruciales pour le contrôle et la prévention de la cryptosporidiose.
Assuntos
Criptosporidiose , Cryptosporidium , Fezes , Serpentes , Animais , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Cryptosporidium/classificação , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , China/epidemiologia , Prevalência , Fezes/parasitologia , Serpentes/parasitologia , Filogenia , Fatores de Risco , Reação em Cadeia da Polimerase/veterinária , Masculino , Feminino , DNA de Protozoário/isolamento & purificação , Diarreia/parasitologia , Diarreia/veterinária , Diarreia/epidemiologia , Animais de Estimação/parasitologiaRESUMO
miR-196b-5p plays a role in various malignancies. We have recently reported its function in regulating adipogenesis. However, it remains to be clarified whether and how miR-196b-5p affects bone cells and bone homeostasis. In this study, in vitro functional experiments showed an inhibitory effect of miR-196b-5p on osteoblast differentiation. Mechanistic explorations revealed that miR-196b-5p directly targeted semaphorin 3a (Sema3a) and inhibited Wnt/ß-catenin signaling. SEMA3A attenuated the impaired osteogenesis induced by miR-196b-5p. Osteoblast-specific miR-196b transgenic mice showed significant reduction of bone mass. Trabecular osteoblasts were reduced and bone formation was suppressed, whereas osteoclasts, marrow adipocytes, and serum levels of bone resorption markers were increased in the transgenic mice. The osteoblastic progenitor cells from the transgenic mice had decreased SEMA3A levels and exhibited retarded osteogenic differentiation, whereas those marrow osteoclastic progenitors exhibited enhanced osteoclastogenic differentiation. miR-196b-5p and SEMA3A oppositely regulated the expression of receptor activator of nuclear factor-κB ligand and osteoprotegerin. The calvarial osteoblastic cells expressing the transgene promoted osteoclastogenesis, whereas the osteoblasts overexpressing Sema3a inhibited it. Finally, in vivo transfection of miR-196b-5p inhibitor to the marrow reduced ovariectomy-induced bone loss in mice. Our study has identified that miR-196b-5p plays a key role in osteoblast and osteoclast differentiation and regulates bone homeostasis. Inhibition of miR-196b-5p may be beneficial for amelioration of osteoporosis. © 2023 American Society for Bone and Mineral Research (ASBMR).
Assuntos
MicroRNAs , Osteoclastos , Animais , Feminino , Camundongos , Diferenciação Celular , Homeostase , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese , Semaforina-3A/genética , Semaforina-3A/metabolismo , Semaforina-3A/farmacologiaRESUMO
PURPOSE: This study prospectively assessed the effects of knee position on blood loss and range of motion after primary total knee arthroplasty (TKA). METHODS: One hundred and ten consecutive TKA patients were randomized into flexion group and extension group. Both groups had the leg elevated 30° at the hip over an inactive CPM for 72 h postoperatively. The flexion group had the knee flexed to 30° during this period. The extension group had the knee extended fully. Perioperative blood loss, hidden blood loss, knee swelling, ecchymosis, analgesia requirements, range of motion (ROM), fixed flexion deformity (FFD), straight-leg raising action, and postoperative complications within 6 weeks of surgery were measured for evaluation and comparison. RESULTS: The postoperative hidden blood loss, knee swelling, and scope of ecchymosis were significantly lower in the flexion group than in the extension group, and ROM and straight-leg raising action were significantly higher during the early period after operation. No significant difference was observed in perioperative blood loss, the amount of morphine used, or FFD in the early postoperative period or in ROM and FFD at 6 weeks postoperatively. CONCLUSIONS: The findings of this study indicate that flexion of the knee to 30° with the leg elevated 30° at the hip after total knee arthroplasty may mitigate knee swelling and provide other beneficial results during the early rehabilitation following TKA. LEVEL OF EVIDENCE: Prospective comparative study, Level I.
Assuntos
Artroplastia do Joelho , Perda Sanguínea Cirúrgica , Articulação do Joelho/fisiologia , Idoso , Artroplastia do Joelho/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Postura/fisiologia , Estudos Prospectivos , Amplitude de Movimento ArticularRESUMO
BACKGROUND: N-myc downstream regulated gene 1 (NDRG1) plays a role in a variety of biological processes including differentiation of osteoclasts. However, it is not known if and how NDRG1 regulates osteogenic differentiation of marrow stromal progenitor cells. METHODS: Gene expression profiling analysis was performed to study the expression level of Ndrg1 during osteogenic and adipogenic differentiation. Gain-of-function and/or loss-of function experiments were carried out to study the role of NDRG1 in the proliferation and differentiation of marrow stromal progenitor cells and the mechanism underlying the function was investigated. Finally, in vivo transfection of Ndrg1 siRNA was done and its effect on osteogenic and adipogenic differentiation in mice was explored. RESULTS: Gene expression profiling analysis revealed that NDRG1 level was regulated during osteogenic and adipogenic differentiation of progenitor cells. The functional experiments demonstrated that NDRG1 negatively regulated the cell growth, and reciprocally modulated the osteogenic and adipogenic commitment of marrow stromal progenitor cells, driving the cells to differentiate toward adipocytes at the expense of osteoblast differentiation. Moreover, NDRG1 interacted with low-density lipoprotein receptor-related protein 6 (LRP6) in the stromal progenitor cells and inactivated the canonical Wnt/ß-catenin signaling cascade. Furthermore, the impaired differentiation of progenitor cells induced by Ndrg1 siRNA could be attenuated when ß-catenin was simultaneously silenced. Finally, in vivo transfection of Ndrg1 siRNA to the marrow of mice prevented the inactivation of canonical Wnt signaling in the BMSCs of ovariectomized mice, and ameliorated the reduction of osteoblasts on the trabeculae and increase of fat accumulation in the marrow observed in the ovariectomized mice. CONCLUSION: This study has provided evidences that NDRG1 plays a role in reciprocally modulating osteogenic and adipogenic commitment of marrow stromal progenitor cells through inactivating canonical Wnt signaling.
Assuntos
Osteogênese , Via de Sinalização Wnt , Animais , Proteínas de Ciclo Celular , Diferenciação Celular/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Osteoblastos/metabolismo , Osteogênese/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismoRESUMO
On March 23, 2010, we successfully treated a boy with synpolydactyly who had a total of 31 fingers and toes. Although there was bone syndactyly both the hands of the boy, one-step correction of four extremities was successful, this operation lasted 5 h and 20 min and intraoperative bleeding was about 50 ml. Skin grafting was successful after operation and all incisions healed well. The appearance and function of hands and feet were satisfactory.
Assuntos
Procedimentos de Cirurgia Plástica/métodos , Polidactilia/cirurgia , Sindactilia/cirurgia , Pré-Escolar , Dedos/anormalidades , Humanos , Masculino , Transplante de Pele , Dedos do Pé/anormalidades , Dedos do Pé/cirurgiaRESUMO
Nanoplastic exposure can potentially cause the severe transgenerational toxicity in organisms. However, the transgenerational nanoplastic toxicity and the underlying mechanisms are still largely unclear. Using Caenorhabditis elegans as an animal model, we here compared the transgenerational toxicity of two sizes of polystyrene nanoparticles (PS-NPs, 20 and 100 nm). The nematodes were exposed to PS-NPs at the P0 generation, and from the F1 generation the nematodes were grown under the normal condition. Exposure to 20 nm PS-NPs resulted in more severe transgenerational toxicity than exposure to 100 nm PS-NPs. At the concentration of 100 µg/L, the toxicity of 20 nm PS-NPs on locomotion and reproduction was detected at the F1-F6 generations, whereas the toxicity of 100 nm PS-NPs could only be observed at the F1-F3 generations. The difference in transgeneration toxicity between PS-NPs (20 nm) and PS-NPs (100 nm) was associated with the difference in transgenerational activation of oxidative stress. Based on observations on SOD-3::GFP, HSP-6::GFP, and HSP-4::GFP expressions, PS-NPs (20 nm) and PS-NPs (100 nm) further induced different transgenerational responses of anti-oxidation, mt UPR, and ER UPR. Our data suggested that the induction of transgenerational toxicity of PS-NPs was size dependent in nematodes. The results are helpful for our understanding the cellular mechanisms for the induction of transgenerational nanoplastic toxicity in organisms.
Assuntos
Caenorhabditis elegans , Nanopartículas , Animais , Microplásticos , Nanopartículas/toxicidade , Poliestirenos , ReproduçãoRESUMO
Caenorhabditis elegans is a useful animal model to assess nanoplastic toxicity. Using polystyrene nanoparticles (PS-NPs) as the example of nanoplastics, we found that exposure to PS-NPs (1-100 µg/L) from L1-larvae for 6.5 days increased expression of cbp-1 encoding an acetyltransferase. The susceptibility to PS-NPs toxicity was observed in cbp-1(RNAi) worms, suggesting that CBP-1-mediated histone acetylation regulation reflects a protective response to PS-NPs. The functions of CBP-1 in intestine, neurons, and germline were required for formation of this protective response. In intestinal cells, CBP-1 controlled PS-NPs toxicity by modulating functions of insulin and p38 MAPK signaling pathways. In neuronal cells, CBP-1 controlled PS-NPs toxicity by affecting functions of DAF-7/TGF-ß and JNK MAPK signaling pathways. In germline cells, CBP-1 controlled PS-NPs toxicity by suppressing NHL-2 activity, and NHL-2 further regulated PS-NPs toxicity by modulating insulin communication between germline and intestine. Therefore, our data suggested that the CBP-1-mediated histone acetylation regulation in certain tissues is associated with the induction of protective response to PS-NPs in C. elegans.
Assuntos
Proteínas de Caenorhabditis elegans , Nanopartículas , Acetilação , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Histona Acetiltransferases , Nanopartículas/toxicidade , Poliestirenos , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: Sprouty (SPRY) proteins play critical roles in controlling cell proliferation, differentiation, and survival by inhibiting receptor tyrosine kinase (RTK)-mediated extracellular signal-regulated kinase (ERK) signaling. Recent studies have demonstrated that SPRY4 negatively regulates angiogenesis and tumor growth. However, whether SPRY4 regulates osteogenic and/or adipogenic differentiation of mesenchymal stem cells remains to be explored. RESULTS: In this study, we investigated the expression pattern of Spry4 and found that its expression was regulated during the differentiation of mouse marrow stromal progenitor cells and increased in the metaphysis of ovariectomized mice. In vitro loss-of-function and gain-of-function studies demonstrated that SPRY4 inhibited osteogenic differentiation and stimulated adipogenic differentiation of progenitor cells. In vivo experiments showed that silencing of Spry4 in the marrow of C57BL/6 mice blocked fat accumulation and promoted osteoblast differentiation in ovariectomized mice. Mechanistic investigations revealed the inhibitory effect of SPRY4 on canonical wingless-type MMTV integration site (Wnt) signaling and ERK pathway. ERK1/2 was shown to interact with low-density lipoprotein receptor-related protein 6 (LRP6) and activate the canonical Wnt signaling pathway. Inactivation of Wnt signaling attenuated the inhibition of adipogenic differentiation and stimulation of osteogenic differentiation by Spry4 small interfering RNA (siRNA). Finally, promoter study revealed that ß-catenin transcriptionally inhibited the expression of Spry4. CONCLUSIONS: Our study for the first time suggests that a novel SPRY4-ERK1/2-Wnt/ß-catenin regulatory loop exists in marrow stromal progenitor cells and plays a key role in cell fate determination. It also highlights the potential of SPRY4 as a novel therapeutic target for the treatment of metabolic bone disorders such as osteoporosis.
Assuntos
Adipogenia/genética , Adipogenia/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Células-Tronco Mesenquimais/fisiologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Osteogênese/genética , Osteogênese/fisiologia , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia , beta Catenina/genética , beta Catenina/fisiologia , Animais , Medula Óssea/metabolismo , Feminino , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , RNA Interferente Pequeno/farmacologiaRESUMO
Long noncoding RNAs (LncRNAs) have been implicated in the regulation of adipocyte and osteoblast differentiation. However, the functional contributions of LncRNAs to adipocyte or osteoblast differentiation remain largely unexplored. In the current study we have identified a novel LncRNA named peroxisome proliferator-activated receptor γ coactivator-1ß-OT1 (PGC1ß-OT1). The expression levels of PGC1ß-OT1 were altered during adipogenic and osteogenic differentiation from progenitor cells. 5'- and 3'-rapid amplification of cDNA ends (RACE) revealed that PGC1ß-OT1 is 1759 nt in full length. Overexpression of PGC1ß-OT1 in progenitor cells inhibited adipogenic differentiation, whereas silencing of endogenous PGC1ß-OT1 induced adipogenic differentiation. By contrast, overexpression of PGC1ß-OT1 in progenitor cells stimulated, whereas silencing of PGC1ß-OT1 inhibited osteogenic differentiation. In vivo experiment showed that silencing of endogenous PGC1ß-OT1 in marrow stimulated fat accumulation and decreased osteoblast differentiation in mice. Mechanism investigations revealed that PGC1ß-OT1 contains a functional miR-148a-3p binding site. Overexpression of the mutant PGC1ß-OT1 with mutation at the binding site failed to regulate either adipogenic or osteogenic differentiation. In vivo crosslinking combined with affinity purification studies demonstrated that PGC1ß-OT1 physically associated with miR-148a-3p through the functional miR-148a-3p binding site. Furthermore, PGC1ß-OT1 affected the expression of endogenous miR-148a-3p and its target gene lysine-specific demethylase 6b (KDM6B). Supplementation of miR-148a-3p in progenitor cells blocked the inhibitory effect of PGC1ß-OT1 on adipocyte formation. Moreover, overexpression of Kdm6b restored the osteoblast differentiation which was inhibited by silencing of endogenous PGC1ß-OT. Our studies provide evidences that the novel LncRNA PGC1ß-OT1 reciprocally regulates adipogenic and osteogenic differentiation through antagonizing miR-148a-3p and enhancing KDM6B effect.
Assuntos
Adipócitos/metabolismo , MicroRNAs/antagonistas & inibidores , Osteoblastos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , RNA Longo não Codificante/metabolismo , Células 3T3 , Adipócitos/citologia , Animais , Diferenciação Celular/fisiologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoblastos/citologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Longo não Codificante/genética , TransfecçãoRESUMO
Repairing soft tissue loss in feet's anterior and middle parts has become a problem, especially for children. We observed the feasibility and clinical effects of superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery for repairing children's feet.Between January 2015 and December 2016, soft tissue loss in anterior and middle regions of feet were repaired using superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery in 8 children with a median age of 6.5 [4-9, interquartile range (IQR)â=â3] years. The skin of lower leg was intact, and the soft tissue loss area was located in the anterior and middle regions of feet with a size of 5âcmâ×â4âcm to 11âcmâ×â7âcm combined with the exposure of tendons and joints in all the 8 children. On the basis of the conditions above, there were no indications of free skin grafting. Foot wounds were repaired all with the superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery (6âcmâ×â5âcm to 12âcmâ×â8âcm), and then the donor area was sutured to narrow the donor area followed by intermediate split thickness skin graft. The perforating branch trunk of peroneal artery was used as a rotation point (4âcm above the lateral malleolus) in 5 children and descending branch of perforating branch of peroneal artery as a rotation point (2âcm under the lateral malleolus) in 3 children.All flaps survived with primary healing in the 8 children. Postoperative median 7.5-month (3-12, IQRâ=â4.5) follow-up indicated that flap color and texture were fine, the appearances of donor and recipient areas were satisfactory, wearing shoes was not affected, and walking function and foot blood circulation were normal.For intractable soft tissue loss in the anterior and middle regions of children's feet, superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery can improve recipient area appearance and walking function because it has the characteristics of reliable blood supply and convenient rotation. It is worth using this method widely in clinics.
Assuntos
Traumatismos do Pé/cirurgia , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Criança , Pré-Escolar , Estudos de Coortes , Estudos de Viabilidade , Feminino , Traumatismos do Pé/patologia , Humanos , Masculino , Lesões dos Tecidos Moles/patologia , Resultado do Tratamento , CicatrizaçãoRESUMO
Incidence of melanoma is increasing annually worldwide. There remains a lack of suitable treatment methods which can significantly improve the 5-year survival rates of patients. It is established that micro RNAs (miRNAs) have important roles in the diagnosis and treatment of cancer. MiR-337 had been reported to regulate the development of variety of cancers, as a cancer suppressive factor. In our research we found that miR-337 had a lower expression in melanoma than adjacent tissues. The patients who had a lower miR-337 also got a worse survival. MiR-337 could target STAT3 to regulate the occurrence and development of melanoma. In summary, our findings suggest that the miR-337/STAT3 axis may serve as a potential target for the treatment of melanoma.
Assuntos
Melanoma/metabolismo , MicroRNAs/fisiologia , Neoplasias Cutâneas/metabolismo , Regiões 3' não Traduzidas , Adulto , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Interferência de RNA , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologiaRESUMO
Recent emerging studies of miRNAs in mesenchymal stem cell commitment toward adipocyte and osteoblast provide new insights for the understanding of the molecular basis of adipogenesis and osteogenesis. The current study revealed that miR-148a-3p was altered in primary cultured marrow stromal cells and established stromal ST2 line after adipogenic and/or osteogenic treatment. Supplementing miR-148a-3p activity inhibited cell growth and induced ST2 to differentiate into mature adipocytes. Conversely, inactivation of the endogenous miR-148a-3p suppressed ST2 to fully differentiate. By contrast, supplementation of the miR-148a-3p blunted osteoblast differentiation. Lysine-specific demethylase 6b (Kdm6b), a recently identified regulator of osteoblast differentiation was shown to be a direct target of miR-148a-3p by using the luciferase assay. Overexpression of Kdm6b attenuated miR-148a-3p stimulation of adipogenic differentiation. Taken together, our study provides evidences that miR-148a-3p reciprocally regulates adipocyte and osteoblast differentiation through directly targeting Kdm6b.