RESUMEN
Giardia intestinalis is a major diarrhea-causing parasite that colonizes the proximal small intestine of humans and various other mammalian species, including pets and livestock. Despite its global occurrence, there is limited information about the epidemiology of Giardia in reptiles, particularly snakes. The aim of this study was to amplify the beta-giardin (bg) gene of Giardia by polymerase chain reaction (PCR), followed by a comparative evolutionary tree analysis to determine the occurrence and molecular characterization of Giardia in snakes. We collected 603 asymptomatic samples from 26 provinces in China, representing species such as Pantherophis guttatus, Pantherophis obsoletus, Pituophis melanoleucus, Thamnophis sirtalis, Lampropeltis getula, and Heterodon nasicus. Ultimately, a occurrence of Giardia infection of 4.15â¯% was detected in these snakes, with corn snakes (Pantherophis guttatus) having a significantly higher occurrence than other species. Molecular analysis identified assemblage F as the predominant genotype, and also identified an assemblage B that can infect humans and a variety of mammals. The results of this study illustrate the potential risk of transmission of Giardia from snakes to humans, especially in environments where close contact occurs. The present epidemiological study examines epidemiological investigations of Giardia in reptiles, provides data to understand the zoonotic risk of Giardia, and emphasizes the need for targeted surveillance, stringent hygiene measures, and public awareness campaigns to reduce these risks.
RESUMEN
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.
Asunto(s)
Criptosporidiosis , Cryptosporidium , Heces , Serpientes , Animales , Cryptosporidium/genética , Cryptosporidium/aislamiento & purificación , Cryptosporidium/clasificación , Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , China/epidemiología , Prevalencia , Heces/parasitología , Serpientes/parasitología , Filogenia , Factores de Riesgo , Reacción en Cadena de la Polimerasa/veterinaria , Masculino , Femenino , ADN Protozoario/aislamiento & purificación , Diarrea/parasitología , Diarrea/veterinaria , Diarrea/epidemiología , Mascotas/parasitologíaRESUMEN
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.
RESUMEN
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.
Asunto(s)
Adipogénesis , PPAR gamma , Ratones , Animales , Adipogénesis/fisiología , PPAR gamma/genética , PPAR gamma/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Adipocitos/metabolismo , Ratones Endogámicos C3H , Diferenciación Celular , Obesidad/metabolismo , Células 3T3-L1RESUMEN
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).
Asunto(s)
MicroARNs , Osteoclastos , Animales , Femenino , Ratones , Diferenciación Celular , Homeostasis , Ratones Transgénicos , MicroARNs/genética , MicroARNs/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogénesis , Semaforina-3A/genética , Semaforina-3A/metabolismo , Semaforina-3A/farmacologíaRESUMEN
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.
Asunto(s)
Adipogénesis , Proteínas de Microfilamentos , Proteínas de Neoplasias , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores , Humanos , Diferenciación Celular , Proteínas de Microfilamentos/genética , Proteínas de Neoplasias/genética , Fosforilación , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/genéticaRESUMEN
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.
Asunto(s)
Osteogénesis , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Adipocitos/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Diferenciación Celular/fisiología , Proteínas del Ojo/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/farmacología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Osteoblastos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
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.
Asunto(s)
Osteogénesis , Vía de Señalización Wnt , Animales , Proteínas de Ciclo Celular , Diferenciación Celular/fisiología , Péptidos y Proteínas de Señalización Intracelular , Ratones , Osteoblastos/metabolismo , Osteogénesis/genética , Vía de Señalización Wnt/genética , beta Catenina/genética , beta Catenina/metabolismoRESUMEN
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.
Asunto(s)
Huesos/metabolismo , Diferenciación Celular/genética , Proteínas de Microfilamentos/genética , Proteínas de Neoplasias/genética , Osteoblastos/metabolismo , Vía de Señalización Wnt/genética , beta Catenina/genética , Familia-src Quinasas/genética , Animales , Western Blotting , Células Cultivadas , Femenino , Regulación de la Expresión Génica , Homeostasis/genética , Humanos , Ratones Endogámicos C57BL , Proteínas de Microfilamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Osteoblastos/citología , Osteogénesis/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , beta Catenina/metabolismo , Familia-src Quinasas/metabolismoRESUMEN
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.
Asunto(s)
Caenorhabditis elegans , Nanopartículas , Animales , Microplásticos , Nanopartículas/toxicidad , Poliestirenos , ReproducciónRESUMEN
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.
Asunto(s)
Proteínas de Caenorhabditis elegans , Nanopartículas , Acetilación , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Histona Acetiltransferasas , Nanopartículas/toxicidad , Poliestirenos , Factores de Transcripción/metabolismoRESUMEN
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.
Asunto(s)
Proteínas de Caenorhabditis elegans/fisiología , Caenorhabditis elegans/metabolismo , Insulina/fisiología , Receptores Notch/fisiología , Simulación de Ingravidez , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/antagonistas & inhibidores , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Células Germinativas/metabolismo , Intestinos , Especificidad de Órganos , Interferencia de ARN , Receptores Notch/antagonistas & inhibidores , Receptores Notch/genética , Transducción de Señal , Estrés FisiológicoRESUMEN
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.
Asunto(s)
Adipogénesis/genética , Adipogénesis/fisiología , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Sistema de Señalización de MAP Quinasas/genética , Sistema de Señalización de MAP Quinasas/fisiología , Células Madre Mesenquimatosas/fisiología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/fisiología , Osteogénesis/genética , Osteogénesis/fisiología , Vía de Señalización Wnt/genética , Vía de Señalización Wnt/fisiología , beta Catenina/genética , beta Catenina/fisiología , Animales , Médula Ósea/metabolismo , Femenino , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad/fisiología , Ratones , Ratones Endogámicos C57BL , Ovariectomía , ARN Interferente Pequeño/farmacologíaRESUMEN
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.
Asunto(s)
Receptores del Ácido Lisofosfatídico/metabolismo , Células Madre/metabolismo , beta Catenina/metabolismo , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Animales , Diferenciación Celular , RatonesRESUMEN
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.
Asunto(s)
Adipocitos/metabolismo , MicroARNs/antagonistas & inhibidores , Osteoblastos/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , ARN Largo no Codificante/metabolismo , Células 3T3 , Adipocitos/citología , Animales , Diferenciación Celular/fisiología , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Osteoblastos/citología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , ARN Largo no Codificante/genética , TransfecciónRESUMEN
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.
Asunto(s)
Lesiones por Desenguantamiento/terapia , Trasplante de Piel , Temperatura , Adulto , Lesiones por Desenguantamiento/patología , Femenino , Estudios de Seguimiento , Tejido de Granulación/patología , Humanos , Persona de Mediana Edad , Proyectos Piloto , Piel/patología , Trasplante AutólogoRESUMEN
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.
Asunto(s)
Traumatismos de los Pies/cirugía , Procedimientos de Cirugía Plástica , Traumatismos de los Tejidos Blandos/cirugía , Colgajos Quirúrgicos/irrigación sanguínea , Niño , Preescolar , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Traumatismos de los Pies/patología , Humanos , Masculino , Traumatismos de los Tejidos Blandos/patología , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
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.
Asunto(s)
Adipogénesis , Histona Demetilasas con Dominio de Jumonji/metabolismo , MicroARNs/metabolismo , Osteogénesis , Animales , Línea Celular , Células Cultivadas , Histona Demetilasas con Dominio de Jumonji/genética , Ratones , Ratones Endogámicos C57BL , Osteoblastos/metabolismoRESUMEN
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.
Asunto(s)
Melanoma/metabolismo , MicroARNs/fisiología , Neoplasias Cutáneas/metabolismo , Regiones no Traducidas 3' , Adulto , Secuencia de Bases , Sitios de Unión , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Interferencia de ARN , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patologíaRESUMEN
The present study aimed to analyze the expression of genes involved in Dupuytren's contracture (DC), using bioinformatic methods. The profile of GSE21221 was downloaded from the gene expression ominibus, which included six samples, derived from fibroblasts and six healthy control samples, derived from carpal-tunnel fibroblasts. A Distributed Intrusion Detection System was used in order to identify differentially expressed genes. The term contrary genes is proposed. Contrary genes were the genes that exhibited opposite expression patterns in the positive and negative groups, and likely exhibited opposite functions. These were identified using Coexpress software. Gene ontology (GO) function analysis was conducted for the contrary genes. A network of GO terms was constructed using the reduce and visualize gene ontology database. Significantly expressed genes (801) and contrary genes (98) were screened. A significant association was observed between Chitinase-3-like protein 1 and ten genes in the positive gene set. Positive regulation of transcription and the activation of nuclear factor-κB (NF-κB)-inducing kinase activity exhibited the highest degree values in the network of GO terms. In the present study, the expression of genes involved in the development of DC was analyzed, and the concept of contrary genes proposed. The genes identified in the present study are involved in the positive regulation of transcription and activation of NF-κB-inducing kinase activity. The contrary genes and GO terms identified in the present study may potentially be used for DC diagnosis and treatment.