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1.
In Vivo ; 33(4): 1095-1102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31280197

RESUMO

BACKGROUND/AIM: Perinatal diethylstilbestrol (DES) treatment induces the polyovular follicle containing two or more oocytes in a follicle of mouse ovary through estrogen receptor (ER) ß. The aim of the study was to investigate the direct effects of DES on the neonatal mouse ovary and the gene expression of activins. MATERIALS AND METHODS: Ovaries from neonatal wild-type (WT) or ERß- knockout (ERßKO) mice were organ-cultured in a serum-free medium with or without DES, and polyovular follicle induction and expression of activin signaling related genes were examined. RESULTS: The polyovular follicle and cyst incidence in DES-treated organ-cultured ovaries from WT mice, but not from ERßKO mice, was significantly higher than that of control non-treated cultures. DES altered inhibin (Inh) a, Inhba and Inhbb expression in organ-cultured ovaries from C57BL/6J mice, while no change in Inha and an increase of Inhbb were observed by DES, in both WT and ERßKO mice. CONCLUSION: Alterations in activin signaling are involved in the polyovular follicle induction by DES.


Assuntos
Ativinas/genética , Dietilestilbestrol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ativinas/metabolismo , Animais , Animais Recém-Nascidos , Biomarcadores , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Inibinas/genética , Inibinas/metabolismo , Camundongos , Camundongos Knockout , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , RNA Mensageiro/genética
2.
Ann Hematol ; 98(7): 1583-1592, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31041514

RESUMO

Despite the advances in the management of hemoglobinopathies, further insight into disease pathophysiology is necessary to improve our therapeutic approach. Activin-A has emerged as a regulator of erythropoiesis and bone turnover in malignant disorders; however, clinical data in hemoglobinopathies are currently scarce. Thus, we aimed to investigate the role of activin-A among hemoglobinopathy patients and evaluate the rationale of its targeting. Circulating levels of activin-A were measured in patients (n = 227) with beta-thalassemia major (TM) (n = 58), beta-thalassemia intermedia (TI) (n = 43), double heterozygous sickle cell/beta-thalassemia (HbS/beta-thal) (n = 109), or homozygous sickle cell disease (n = 17), and we explored possible correlations with clinical and laboratory data. Seventeen age- and gender-matched, healthy individuals served as controls. Bone marrow density (BMD) was determined using dual-energy X-ray absorptiometry. TM and HbS/beta-thal patients had elevated activin-A compared to controls (p = 0.041 and p = 0.038, respectively). In TM patients, high circulating activin-A showed strong correlations with hemolysis markers, namely reticulocyte count (p = 0.011) and high lactate dehydrogenase (LDH; p = 0.024). Similarly, in HbS/beta-thal patients, activin-A showed positive correlations with indirect bilirubin (p < 0.001), ferritin (p = 0.005), and LDH (p = 0.044). High activin-A correlated with low Z-score of both lumbar spine BMD in TI patients (p < 0.01) and femoral neck BMD in TM patients (p < 0.01). Serum activin-A is elevated in patients with TM and HbS/beta-thal and correlates with markers of hemolysis and low BMD. These data support a role of activin-A in the biology of these disorders and provide further rationale for the broader clinical development of activin-A inhibitors in this setting.


Assuntos
Ativinas/sangue , Anemia Falciforme , Densidade Óssea , Hemólise , Heterozigoto , Talassemia beta , Ativinas/genética , Adulto , Idoso , Anemia Falciforme/sangue , Anemia Falciforme/genética , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Reticulócitos , Talassemia beta/sangue , Talassemia beta/genética
3.
Int J Mol Med ; 43(6): 2329-2340, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31017256

RESUMO

Ameloblastoma is a common odontogenic benign tumor located in the jaws and is characterized by severe local bone destruction. The current study aimed to investigate the effect of interactions between tumor cells and bone marrow stromal cells (BMSCs) on osteoclast formation in ameloblastoma. The impact of ameloblastoma/BMSC interactions on cytokine production, gene expression and osteoclastogenesis was examined using an immortalized ameloblastoma cell line that the authors' previously established. The results demonstrated that interactions between ameloblastoma cells and BMSCs increased interleukin (IL)­8 and activin A secretion by BMSCs. IL­8 expression in BMSCs was modulated by tumor­derived tumor necrosis factor­α and IL­8 contributed to osteoclast formation not only directly but also by stimulating receptor activator of NF­κB ligand (RANKL) expression in BMSCs. Activin A secretion in BMSCs was stimulated by ameloblastoma cells via cell­to­cell­mediated activation of c­Jun N­terminal kinase activation, acting as a cofactor of RANKL to induce osteoclast formation and function. The present study highlights the critical role of communication between BMSCs and ameloblastoma cells in bone resorption in ameloblastoma.


Assuntos
Ativinas/genética , Ameloblastoma/genética , Interleucina-8/genética , Neoplasias Maxilomandibulares/genética , Osteoclastos/patologia , Osteólise/genética , Regulação para Cima , Adulto , Ameloblastoma/complicações , Ameloblastoma/patologia , Células Cultivadas , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Maxilomandibulares/complicações , Neoplasias Maxilomandibulares/patologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Osteoclastos/metabolismo , Osteólise/complicações , Osteólise/patologia , Células Tumorais Cultivadas , Adulto Jovem
4.
Endocrinology ; 160(5): 1097-1110, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874767

RESUMO

Activins and inhibins are closely related protein heterodimers with a similar tissue distribution; however, these two complexes have opposing functions in development and disease. Both are secreted cytokine hormones, with activin the primary inducer of downstream signaling cascades and inhibin acting as a rheostat that exquisitely governs activin function. Adding to the complexity of activin signaling, follistatin, a highly glycosylated monomeric protein, binds activin with high affinity and restrains downstream pathway activation but through a mechanism distinct from that of inhibin. These three proteins were first identified as key ovarian hormones in the pituitary-gonadal axis that direct the synthesis and secretion of FSH from the pituitary, hence controlling folliculogenesis. Research during the past 30 years has expanded the roles of these proteins, first by discovering the ubiquitous expression of the trio and then by implicating them in a wide array of biological functions. In concert, these three hormones govern tissue development, homeostasis, and disease in multiple organ systems through diverse autocrine and paracrine mechanisms. In the present study, we have reviewed the actions of activin and its biological inhibitors, inhibin, and follistatin, in mammary gland morphogenesis and cancer.


Assuntos
Ativinas/metabolismo , Folistatina/metabolismo , Inibinas/metabolismo , Glândulas Mamárias Humanas/metabolismo , Ativinas/genética , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Folistatina/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Inibinas/genética , Transdução de Sinais
5.
BMC Biotechnol ; 19(1): 20, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30925874

RESUMO

BACKGROUND: Baculovirus-mediated expression in insect cells is a powerful approach for protein production. However, many existing methods are time-consuming, offer limited options for protein tagging, and are unsuitable for secreted proteins requiring proteolytic maturation, such as TGF-ß family growth factors. RESULTS: To overcome the limitations of traditional baculovirus expression systems, we engineered "FlexiBAC". This system allows recombinant baculovirus formation inside insect cells and reduces the time between initial cloning and protein production to 13 days. FlexiBAC includes 143 shuttle vectors that append combinations of purification tags, fluorescent markers, proteolytic cleavage sites, trafficking signals, and chemical conjugation tags to the termini of the target protein. This system also overexpresses recombinant furin convertase to allow efficient proteolytic processing of secreted proteins. We demonstrate that FlexiBAC can be used to produce high levels of mature, active forms of TGF-ß family growth factors, such as Activin A, as well as other proteins that are typically difficult to reconstitute, such as proteins rich in coiled-coil, low complexity, and disordered domains. CONCLUSIONS: FlexiBAC is a protein expression system for production of both cytosolic proteins and secreted proteins that require proteolytic maturation. The design of FlexiBAC and its expansive complementary shuttle vector system reduces cloning steps and simplifies baculovirus production.


Assuntos
Baculoviridae/genética , Vetores Genéticos/genética , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/genética , Ativinas/biossíntese , Ativinas/genética , Animais , Expressão Gênica , Proteínas Recombinantes/metabolismo , Spodoptera/genética , Transfecção/métodos , Cultura de Vírus/métodos
6.
Diabetes ; 68(3): 587-597, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30530781

RESUMO

Visceral obesity is associated with insulin resistance and higher risk of type 2 diabetes and metabolic diseases. A limited ability of adipose tissues to remodel through the recruitment and differentiation of adipose stem cells (ASCs) is associated with adipose tissue inflammation and fibrosis and the metabolic syndrome. We show that the lower adipogenesis of omental (Om) compared with abdominal subcutaneous (Abdsc) ASCs was associated with greater secretion of TGFß ligands that acted in an autocrine/paracrine loop to activate SMAD2 and suppress adipogenesis. Inhibition of TGFß signaling rescued Om ASC differentiation. In Abdsc ASCs, low concentrations of dexamethasone suppressed TGFß signaling and enhanced adipogenesis, at least in part by increasing TGFBR3 protein that can sequester TGFß ligands. Om ASCs were resistant to these dexamethasone effects; recombinant TGFBR3 increased their differentiation. Pericellular fibrosis, a hallmark of dysfunctional adipose tissue, was greater in Om and correlated with higher level of tissue TGFß signaling activity and lower ASC differentiation. We conclude that glucocorticoids restrain cell-autonomous TGFß signaling in ASCs to facilitate adipogenesis and healthy remodeling in Abdsc and these processes are impaired in Om. Therapies directed at overcoming glucocorticoid resistance in visceral adipose tissue may improve remodeling and help prevent metabolic complications of visceral obesity.


Assuntos
Tecido Adiposo/metabolismo , Fibrose/metabolismo , Glucocorticoides/farmacologia , Omento/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Ativinas/genética , Ativinas/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo/citologia , Adulto , Dexametasona/farmacologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Fibrose/genética , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Omento/efeitos dos fármacos , Proteoglicanas/genética , Proteoglicanas/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Fator de Crescimento Transformador beta/genética , Adulto Jovem
7.
Zebrafish ; 15(6): 536-545, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30183553

RESUMO

Fibrodysplasia Ossificans Progressiva (FOP) is a rare, autosomal dominant genetic disorder in humans characterized by the gradual ossification of fibrous tissues, including skeletal muscle, tendons, and ligaments. In humans, mutations in the Type I BMP/TGFß family member receptor gene, ACVR1, are associated with FOP. Zebrafish acvr1l, previously known as alk8, is the functional ortholog of human ACVR1. We previously created and characterized the first adult zebrafish model for FOP by generating animals harboring heat shock-inducible mCherry-tagged constitutively active Acvr1l (Q204D). Since injury is a known trigger for heterotopic ossification (HO) development in human FOP patients, in this study, we investigated several injury models in Acvr1lQ204D-expressing zebrafish and the subsequent formation of HO. We performed studies of Activin A injection, cardiotoxin (CTX) injection, and caudal fin clip injury. We found that none of these methods resulted in HO formation at the site of injury. However, some of the cardiotoxin-injected and caudal fin-clipped animals did exhibit HO at distant sites, including the body cavity and along the spine. We describe these results in the context of new and exciting reports on FOP, and discuss future studies to better understand the etiology and progression of this disease.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Nadadeiras de Animais/patologia , Animais Geneticamente Modificados/fisiologia , Mutação , Ossificação Heterotópica/fisiopatologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Ativinas/administração & dosagem , Ativinas/genética , Nadadeiras de Animais/lesões , Nadadeiras de Animais/metabolismo , Animais , Animais Geneticamente Modificados/genética , Cardiotoxinas/administração & dosagem , Humanos , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
8.
Bioessays ; 40(11): e1800044, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30264417

RESUMO

The Transforming growth factor beta (TGF-ß) family of secreted proteins regulates a variety of key events in normal development and physiology. In mammals, this family, represented by 33 ligands, including TGF-ß, activins, nodal, bone morphogenetic proteins (BMPs), and growth and differentiation factors (GDFs), regulate biological processes as diverse as cell proliferation, differentiation, apoptosis, metabolism, homeostasis, immune response, wound repair, and endocrine functions. In Drosophila, only 7 members of this family are present, with 4 TGF-ß/BMP and 3 TGF-ß/activin ligands. Studies in the fly have illustrated the role of TGF-ß/BMP ligands during embryogenesis and organ patterning, while the TGF-ß/activin ligands have been implicated in the control of wing growth and neuronal functions. In this review, we focus on the emerging roles of Drosophila TGF-ß/activins in inter-organ communication via long-distance regulation, especially in systemic lipid and carbohydrate homeostasis, and discuss findings relevant to metabolic diseases in humans.


Assuntos
Ativinas/metabolismo , Metabolismo dos Carboidratos/fisiologia , Drosophila/metabolismo , Metabolismo dos Lipídeos/fisiologia , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Ativinas/genética , Animais , Proteínas Morfogenéticas Ósseas/metabolismo
9.
Mol Ther ; 26(10): 2357-2365, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30093305

RESUMO

Synaptic NMDA receptors activating nuclear calcium-driven adaptogenomics control a potent body-own neuroprotective mechanism, referred to as acquired neuroprotection. Viral vector-mediated gene transfer in conjunction with stereotactic surgery has previously demonstrated the proficiency of several nuclear calcium-regulated genes to protect in vivo against brain damage caused by toxic extrasynaptic NMDA receptor signaling following seizures or stroke. Here we used noninvasive nose-to-brain administration of Activin A and SerpinB2, two secreted nuclear calcium-regulated neuroprotectants, for post-injury treatment of brain damage following middle cerebral artery occlusion (MCAO) in C57BL/6N mice. The observed reduction of the infarct volume was comparable to the protection obtained by intracerebroventricular injection of recombinant Activin A or SerpinB2 or by stereotactic delivery 3 weeks prior to the injury of a recombinant adeno-associated virus containing an expression cassette for the potent neuroprotective transcription factor Npas4. These results establish post-injury, nose-to-brain delivery of Activin A and SerpinB2 as effective and possibly clinically applicable treatments of acute and chronic neurodegenerative conditions.


Assuntos
Ativinas/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Isquemia Encefálica/terapia , Inibidor 2 de Ativador de Plasminogênio/genética , Acidente Vascular Cerebral/terapia , Ativinas/administração & dosagem , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/administração & dosagem , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Cálcio/metabolismo , Dependovirus/genética , Modelos Animais de Doenças , Terapia Genética/métodos , Humanos , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/terapia , Infusões Intraventriculares , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neuroproteção/genética , Fármacos Neuroprotetores/administração & dosagem , Inibidor 2 de Ativador de Plasminogênio/administração & dosagem , Receptores de N-Metil-D-Aspartato/genética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Transdução de Sinais/efeitos dos fármacos , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia
10.
Int J Mol Sci ; 19(9)2018 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-30142896

RESUMO

The high cardiovascular mortality associated with chronic kidney disease (CKD) is caused in part by the CKD-mineral bone disorder (CKD-MBD) syndrome. The CKD-MBD consists of skeletal, vascular and cardiac pathology caused by metabolic derangements produced by kidney disease. The prevalence of osteopenia/osteoporosis resulting from the skeletal component of the CKD-MBD, renal osteodystrophy (ROD), in patients with CKD exceeds that of the general population and is a major public health concern. That CKD is associated with compromised bone health is widely accepted, yet the mechanisms underlying impaired bone metabolism in CKD are not fully understood. Therefore, clarification of the molecular mechanisms by which CKD produces ROD is of crucial significance. We have shown that activin A, a member of the transforming growth factor (TGF)-ß super family, is an important positive regulator of receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclastogenesis with Smad-mediated signaling being crucial for inducing osteoclast development and function. Recently, we have demonstrated systemic activation of activin receptors and activin A levels in CKD mouse models, such as diabetic CKD and Alport (AL) syndrome. In these CKD mouse models, bone remodeling caused by increased osteoclast numbers and activated osteoclastic bone resorption was observed and treatment with an activin receptor ligand trap repaired CKD-induced-osteoclastic bone resorption and stimulated individual osteoblastic bone formation, irrespective of parathyroid hormone (PTH) elevation. These findings have opened a new field for exploring mechanisms of activin A-enhanced osteoclast formation and function in CKD. Activin A appears to be a strong candidate for CKD-induced high-turnover ROD. Therefore, the treatment with the decoy receptor for activin A might be a good candidate for treatment for CKD-induced osteopenia or osteoporosis, indicating that the new findings from in these studies will lead to the identification of novel therapeutic targets for CKD-related and osteopenia and osteoporosis in general. In this review, we describe the impact of CKD-induced Smad signaling in osteoclasts, osteoblasts and vascular cells in CKD.


Assuntos
Ativinas/metabolismo , Reabsorção Óssea/metabolismo , Osso e Ossos/metabolismo , Distúrbio Mineral e Ósseo na Doença Renal Crônica/metabolismo , Rim/metabolismo , Transdução de Sinais , Receptores de Ativinas/genética , Receptores de Ativinas/metabolismo , Ativinas/genética , Animais , Remodelação Óssea , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Osso e Ossos/patologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/genética , Distúrbio Mineral e Ósseo na Doença Renal Crônica/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Rim/patologia , Camundongos , Osteogênese/genética , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/patologia , Hormônio Paratireóideo/genética , Hormônio Paratireóideo/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , Proteínas Smad/genética , Proteínas Smad/metabolismo
11.
J Ovarian Res ; 11(1): 34, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29716627

RESUMO

BACKGROUND: The granulosa cells are indispensable for follicular development and its function is orchestrated by several genes, which in turn posttranscriptionally regulated by microRNAs (miRNA). In our previous study, the miRRNA-424/503 cluster was found to be highly abundant in bovine granulosa cells (bGCs) of preovulatory dominant follicle compared to subordinate counterpart at day 19 of the bovine estrous cycle. Other study also indicated the involvement of miR-424/503 cluster in tumour cell resistance to apoptosis suggesting this miRNA cluster may involve in cell survival. However, the role of miR-424/503 cluster in granulosa cell function remains elusive Therefore, this study aimed to investigate the role of miRNA-424/503 cluster in bGCs function using microRNA gain- and loss-of-function approaches. RESULTS: The role of miR-424/503 cluster members in granulosa cell function was investigated by overexpressing or inhibiting its activity in vitro cultured granulosa cells using miR-424/503 mimic or inhibitor, respectively. Luciferase reporter assay showed that SMAD7 and ACVR2A are the direct targets of the miRNA-424/503 cluster members. In line with this, overexpression of miRNA-424/503 cluster members using its mimic and inhibition of its activity by its inhibitor reduced and increased, respectively the expression of SMAD7 and ACVR2A. Furthermore, flow cytometric analysis indicated that overexpression of miRNA-424/503 cluster members enhanced bGCs proliferation by promoting G1- to S- phase cell cycle transition. Modulation of miRNA-424/503 cluster members tended to increase phosphorylation of SMAD2/3 in the Activin signalling pathway. Moreover, sequence specific knockdown of SMAD7, the target gene of miRNA-424/503 cluster members, using small interfering RNA also revealed similar phenotypic and molecular alterations observed when miRNA-424/503 cluster members were overexpressed. Similarly, to get more insight about the role of miRNA-424/503 cluster members in activin signalling pathway, granulosa cells were treated with activin A. Activin A treatment increased cell proliferation and downregulation of both miRNA-424/503 members and its target gene, indicated the presence of negative feedback loop between activin A and the expression of miRNA-424/503. CONCLUSION: This study suggests that the miRNA-424/503 cluster members are involved in regulating bovine granulosa cell proliferation and cell cycle progression. Further, miRNA-424/503 cluster members target the SMAD7 and ACVR2A genes which are involved in the activin signalling pathway.


Assuntos
Receptores de Activinas Tipo II/genética , Células da Granulosa/metabolismo , MicroRNAs/genética , Proteína Smad7/genética , Ativinas/genética , Animais , Apoptose/genética , Bovinos , Pontos de Checagem do Ciclo Celular/genética , Divisão Celular/genética , Proliferação de Células/genética , Ciclo Estral/genética , Feminino , Células da Granulosa/patologia , Humanos , Transdução de Sinais
12.
J Cell Sci ; 131(11)2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29739878

RESUMO

TGF-ß/BMP superfamily ligands require heteromeric complexes of type 1 and 2 receptors for ligand-dependent downstream signaling. Activin A, a TGF-ß superfamily member, inhibits growth of multiple myeloma cells, but the mechanism for this is unknown. We therefore aimed to clarify how activins affect myeloma cell survival. Activin A activates the transcription factors SMAD2/3 through the ALK4 type 1 receptor, but may also activate SMAD1/5/8 through mutated variants of the type 1 receptor ALK2 (also known as ACVR1). We demonstrate that activin A and B activate SMAD1/5/8 in myeloma cells through endogenous wild-type ALK2. Knockdown of the type 2 receptor BMPR2 strongly potentiated activin A- and activin B-induced activation of SMAD1/5/8 and subsequent cell death. Furthermore, activity of BMP6, BMP7 or BMP9, which may also signal via ALK2, was potentiated by knockdown of BMPR2. Similar results were seen in HepG2 liver carcinoma cells. We propose that BMPR2 inhibits ALK2-mediated signaling by preventing ALK2 from oligomerizing with the type 2 receptors ACVR2A and ACVR2B, which are necessary for activation of ALK2 by activins and several BMPs. In conclusion, BMPR2 could be explored as a possible target for therapy in patients with multiple myeloma.This article has an associated First Person interview with the first author of the paper.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Ativinas/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Receptores de Ativinas Tipo I/genética , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Ativinas/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Humanos , Transdução de Sinais
13.
Endocrinology ; 159(7): 2815-2825, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29846546

RESUMO

Bone morphogenetic protein (BMP) 2 and activin A belong to the TGF-ß superfamily and are highly expressed in human endometrium and placenta. Studies have demonstrated that activin A and BMP2 play essential roles in the process of early embryo implantation by promoting human trophoblast cell invasion. However, whether activin A production can be regulated by BMP2 in human trophoblast cells remains unknown. The aim of our study was to determine the effects of BMP2 on activin A production and its role in human trophoblast invasion. Primary human extravillous trophoblast (EVT) cells were used as study models. BMP2 treatment significantly increased inhibin ßA (INHBA) mRNA levels and activin A production without altering inhibin α and inhibin ßB levels. BMP2-induced EVT cell invasion was attenuated by knockdown of INHBA. The increased INHBA transcription and activin A production by BMP2 were blocked by the type I receptor activin receptor (ACVR)-like kinase 2 (ALK2) and activin receptor-like kinase 3 (ALK3) inhibitor dorsomorphin homolog 1 (DMH-1). BMP2-induced INHBA upregulation was also inhibited by knockdown of type I receptor ALK3 or combined knockdown of type II receptors for BMP2 (BMPR2) and ACVR2A. Whereas BMP2 initiated both canonical SMAD1/5/8 and noncanonical SMAD2/3 signaling, only knockdown of SMAD4, but not SMAD2 and SMAD3, abolished the effects of BMP2 on INHBA. Our results show that BMP2 increases human trophoblast invasion by upregulating INHBA and activin A production via ALK3-BMPR2/ACVR2A-SMAD1/5/8-SMAD4 signaling.


Assuntos
Ativinas/metabolismo , Proteína Morfogenética Óssea 2/farmacologia , Trofoblastos/efeitos dos fármacos , Ativinas/genética , Western Blotting , Células Cultivadas , Humanos , Subunidades beta de Inibinas/metabolismo , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Smad1/metabolismo , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad5/metabolismo , Proteína Smad8/metabolismo , Trofoblastos/metabolismo
14.
J Cell Physiol ; 233(9): 7143-7156, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29574773

RESUMO

Uterine leiomyomas (fibroids or myomas) are the most common benign tumors of premenopausal women and new medical treatments are needed. This study aimed to determine the effects of omega-3 fatty acids on the lipid profile, membrane architecture and gene expression patterns of extracellular matrix components (collagen1A1, fibronectin, versican, or activin A), mechanical signaling (integrin ß1, FAK, and AKAP13), sterol regulatory molecules (ABCG1, ABCA1, CAV1, and SREBF2), and mitochondrial enzyme (CYP11A1) in myometrial and leiomyoma cells. Myometrial tissues had a higher amount of arachidonic acid than leiomyoma tissues while leiomyoma tissues had a higher level of linoleic acid than myometrial tissues. Treatment of primary myometrial and leiomyoma cells with eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) reduced the monounsaturated fatty acid (MUFA) content and increased the polyunsaturated fatty acid (PUFA) content in both cell types. Myometrial and leiomyoma cell membranes were in the liquid-crystalline phase, but EPA- and DHA-treated cells had decreased membrane fluidity. While we found no changes in the mRNA expression of ECM components, EPA and DHA treatment reduced levels of ABCG1, ABCA1, and AKAP13 in both cell types. EPA and DHA also reduced FAK and CYP11A1 expression in myometrial cells. The ability of omega-3 fatty acids to remodel membrane architecture and downregulate the expression of genes involved in mechanical signaling and lipid accumulation in leiomyoma cells offers to further investigate this compound as preventive and/or therapeutic option.


Assuntos
Membrana Celular/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Regulação Neoplásica da Expressão Gênica , Leiomioma/genética , Leiomioma/patologia , Lipídeos/química , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Ativinas/genética , Ativinas/metabolismo , Adulto , Membrana Celular/efeitos dos fármacos , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Miométrio/efeitos dos fármacos , Miométrio/metabolismo , Miométrio/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esteróis/metabolismo
15.
Theranostics ; 8(3): 846-859, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344311

RESUMO

Mesenchymal stem cells (MSC) are highly immunosuppressive cells able to reduce chronic inflammation through the active release of mediators. Recently, we showed that glucocorticoid-induced leucine zipper (Gilz) expression by MSC is involved in their therapeutic effect by promoting the generation of regulatory T cells. However, the mechanisms underlying this pivotal role of Gilz remain elusive. Methods and Results In this study, we have uncovered evidence that Gilz modulates the phenotype and function of Th1 and Th17 cells likely by upregulating the level of Activin A and NO2 secreted by MSC. Adoptive transfer experiments sustained this Gilz-dependent suppressive effect of MSC on Th1 and Th17 cell functions. In immunoregulatory MSC, obtained by priming with IFN-γ and TNF-α, Gilz was translocated to the nucleus and bound to the promoters of inos and Activin ßA to induce their expression. The increased expression of Activin A directly impacted on Th17 cells fate by repressing their differentiation program through the activation of Smad3/2 and enhancing IL-10 production. Conclusion Our results reveal how Gilz controls inos and Activin ßA gene expression to ultimately assign immunoregulatory status to MSC able to repress the pathogenic Th17 cell differentiation program and uncover Activin A as a novel mediator of MSC in this process.


Assuntos
Ativinas/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/imunologia , Células Th17/imunologia , Fatores de Transcrição/metabolismo , Ativinas/genética , Animais , Células Cultivadas , Apresentação Cruzada , Interferon gama/metabolismo , Interleucina-10/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Smad/metabolismo , Células Th17/citologia , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/metabolismo
16.
J Dermatol Sci ; 90(1): 13-20, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29290529

RESUMO

BACKGROUND: Histone deacetylase (HDAC) is an enzyme that regulates gene expression, cell cycle arrest, apoptosis and modulation of various pathways. HDAC inhibitors (HDACis) can modulate these pathways by hyper-acetylating target proteins, thereby acting as cancer chemotherapeutic agents. OBJECTIVE: One of HDACis, suberoylanilide hydroxamic acid (SAHA), has been found to regulate the Smad signaling pathway, by an as yet unclear mechanism. This study therefore investigated the mechanism by which SAHA regulates Smad signaling in the melanoma cell line SK-Mel-5. METHODS: Cell proliferation was assessed by MTT assays and fluorescence activated cell sorter (FACS) analysis. The activation of Smad signaling pathway was assessed by western blots analysis. The transcriptions of target genes were checked by RT-PCR and dual luciferase assay. RESULTS: Treatment with SAHA inhibited the proliferation of SK-Mel-5 cells, enhanced the phosphorylation of R-Smad, and up-regulated p21 protein. Surprisingly, R-Smad was also activated by conditioned medium from SAHA-treated SK-Mel-5 cells. An analysis of the conditioned medium showed that activin A was responsible for the activation of R-Smad. SAHA treatment enhanced the level of activin A mRNA, increasing the level of activin A in the secretome. The activity of the SAHA-treated secretome could be eliminated by pre-incubation with antibody to activin A. In addition, activin A supplemented medium could mimic the effect of the SAHA-treated secretome. CONCLUSION: These findings indicate that the anti-cancer function of SAHA is mediated, at least in part, by the upregulation of activin A.


Assuntos
Ativinas/metabolismo , Antineoplásicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Acetilação , Ativinas/genética , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Separação Celular/métodos , Meios de Cultivo Condicionados/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Citometria de Fluxo/métodos , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico , Melanoma/tratamento farmacológico , RNA Mensageiro/metabolismo , Proteínas Smad Reguladas por Receptor , Regulação para Cima , Vorinostat
17.
Mol Cell Endocrinol ; 470: 188-198, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29111388

RESUMO

Regionalised interaction of the activins, follistatin and inhibin was investigated in the male reproductive tract of mice lacking the inhibin α-subunit (Inha-/-). Serum and intratesticular activin B, although not activin A and follistatin, were increased in Inha-/- mice at 25 days of age, but all three proteins were elevated at 56 days. None of these proteins were altered within the epididymis and vas deferens at either age. At 25 days, histology of the epididymis and vas deferens was similar to wild-type. At 56 days, the testis contained extensive somatic cell tumours, leading to Leydig cell regression and testosterone deficiency. The epididymis and vas deferens showed epithelial regression and increased prominence of the interstitial stroma. Immunoregulatory and fibrotic gene expression in the epididymis and vas deferens were unchanged. Thus, absence of the inhibin α-subunit has marginal effects on activins in the epididymis and vas deferens, and regression of these tissues is associated with androgen deficiency.


Assuntos
Ativinas/metabolismo , Androgênios/deficiência , Inibinas/genética , Testículo/metabolismo , Testículo/patologia , Ativinas/sangue , Ativinas/genética , Envelhecimento/patologia , Animais , Epididimo/patologia , Folistatina/sangue , Folistatina/genética , Regulação da Expressão Gênica , Inibinas/deficiência , Inibinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fenótipo , Células Estromais/metabolismo , Células Estromais/patologia , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia , Ducto Deferente/patologia
18.
Biochim Biophys Acta Mol Basis Dis ; 1864(3): 891-899, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29287776

RESUMO

BACKGROUND & AIMS: TGFß superfamily member Activin-A is a multifunctional hormone/cytokine expressed in multiple tissues and cells, where it regulates cellular differentiation, proliferation, inflammation and tissue architecture. High activin-A levels have been reported in alcoholic cirrhosis and non-alcoholic steatohepatitis (NASH). Our aim was to identify the cell types involved in the fibrotic processes induced by activin-A in liver and verify the liver diseases that this molecule can be found increased. METHODS: We studied the effect of activin-A on mouse primary Kupffer cells (KCs) and Hepatic Stellate cells (HSCs) and the levels of activin-A and its inhibitor follistatin in the serum of patients from a large panel of liver diseases. RESULTS: Activin-A is expressed by mouse hepatocytes, HSCs and Liver Sinusoid Endothelial cells but not KCs. Each cell type expresses different activin receptor combinations. HSCs are unresponsive to activin-A due to downregulation/desensitization of type-II activin receptors, while KCs respond by increasing the expression/production of TNFα και TGFß1. In the presence of KCs or conditioned medium from activin-A treated KCs, HSCs switch to a profibrogenic phenotype, including increased collagen and αSMA expression and migratory capacity. Incubation of activin-A treated KC conditioned medium with antibodies against TNFα and TGFß1 partially blocks its capacity to activate HSCs. Only patients with alcoholic liver diseases and NASH cirrhosis have significantly higher activin-A levels and activin-A/follistatin ratio. CONCLUSIONS: Activin-A may induce fibrosis in NASH and alcoholic cirrhosis via activation of KCs to express pro-inflammatory molecules that promote HSC-dependent fibrogenesis and could be a target for future anti-fibrotic therapies.


Assuntos
Ativinas/fisiologia , Células Estreladas do Fígado/metabolismo , Macrófagos do Fígado/metabolismo , Fígado/patologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ativinas/genética , Ativinas/metabolismo , Idoso , Animais , Estudos de Casos e Controles , Fibrose/genética , Fibrose/metabolismo , Humanos , Macrófagos do Fígado/patologia , Fígado/metabolismo , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Fator de Crescimento Transformador beta/genética , Fator de Necrose Tumoral alfa/genética
19.
J Cell Mol Med ; 22(1): 173-184, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28834227

RESUMO

Acute ischaemia causes a significant loss of blood vessels leading to deterioration of organ function. Multiple ischaemic conditions are associated with up-regulation of activin A, but its effect on endothelial cells (EC) in the context of hypoxia is understudied. This study evaluated the role of activin A in vasculogenesis in hypoxia. An in vitro vasculogenesis model, in which EC were cocultured with adipose stromal cells (ASC), was used. Incubation of cocultures at 0.5% oxygen led to decrease in EC survival and vessel density. Hypoxia up-regulated inhibin BA (monomer of activin A) mRNA by 4.5-fold and activin A accumulation in EC-conditioned media by 10-fold, but down-regulated activin A inhibitor follistatin by twofold. Inhibin BA expression was also increased in human EC injected into ischaemic mouse muscles. Activin A secretion was positively modulated by hypoxia mimetics dimethyloxalylglycine and desferrioxamine. Silencing HIF1α or HIF2α expression decreased activin A secretion in EC exposed to hypoxia. Introduction of activin A to cocultures decreased EC number and vascular density by 40%; conversely, blockade of activin A expression in EC or its activity improved vasculogenesis in hypoxia. Activin A affected EC survival directly and by modulating ASC paracrine activity leading to diminished ability of the ASC secretome to support EC survival and vasculogenesis. In conclusion, hypoxia up-regulates EC secretion of activin A, which, by affecting both EC and adjacent mesenchymal cells, creates a micro-environment unfavourable for vasculogenesis. This finding suggests that blockade of activin A signalling in ischaemic tissue may improve preservation of the affected tissue.


Assuntos
Ativinas/metabolismo , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Ativinas/genética , Animais , Hipóxia Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Recém-Nascido , Isquemia/patologia , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
J Allergy Clin Immunol ; 141(2): 671-684.e7, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28579377

RESUMO

BACKGROUND: Previously, we demonstrated that regulatory T (Treg) cells induced by the cytokine activin-A suppress TH2-mediated allergic responses and linked airway disease. Still, the effects of activin-A-induced regulatory T (Act-A-iTreg) cells on the regulation of dendritic cell (DC)-driven allergic inflammation remain elusive. OBJECTIVE: Here we investigated whether Act-A-iTreg cells can modulate DC responses and endow them with enhanced tolerogenic functions. METHODS: Using adoptive cell transfer studies in mouse models of allergic airway disease, we examined the effects of Act-A-iTreg cells on DC phenotype, maturation status, and TH2 cell priming potential. Genome-wide gene expression profiling characterized the transcriptional networks induced in tolerogenic DCs by Act-A-iTreg cells. The ability of DCs conditioned by Act-A-iTreg cells (Act-A-iTreg cell-modified DCs) to protect against experimental asthma, and the mechanisms involved were also explored. RESULTS: Act-A-iTreg cell-modified DCs exhibited a significantly impaired capacity to uptake allergen and stimulate naive and TH2 effector responses on allergen stimulation in vivo accompanied by markedly attenuated inflammatory cytokine release in response to LPS. Gene-profiling studies revealed that Act-A-iTreg cells dampened crucial TH2-skewing transcriptional networks in DCs. Administration of Act-A-iTreg cell-modified DCs ameliorated cardinal asthma manifestations in preventive and therapeutic protocols through generation of strongly suppressive forkhead box P3+ Treg cells. Finally, programed death protein 1/programmed death ligand 1 signaling pathways were essential in potentiating the generation of DCs with tolerogenic properties by Act-A-iTreg cells. CONCLUSION: Our studies reveal that Act-A-iTreg cells instruct the generation of a highly effective immunoregulatory circuit encompassing tolerogenic DCs and forkhead box P3+ Treg cells that could be targeted for the design of novel immunotherapies for allergic disorders.


Assuntos
Ativinas/imunologia , Asma/prevenção & controle , Células Dendríticas/imunologia , Transdução de Sinais/imunologia , Ativinas/genética , Animais , Asma/genética , Asma/imunologia , Asma/patologia , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Células Dendríticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Transdução de Sinais/genética , Linfócitos T Reguladores , Células Th2/imunologia , Células Th2/patologia , Transcrição Genética/genética , Transcrição Genética/imunologia
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