Search results for "activin"

Growth and differentiation factor 11 (GDF11): Functions in the regulation of erythropoiesis and cardiac regeneration

2015

International audience; Members of the TGF-β superfamily transduce their signals through type I and II receptor serine/threonine kinases. The binding of activins to activin type IIA (ActRIIA) or type IIB (ActRIIB) receptors induces the recruitment and phosphorylation of an activin type I receptor (ALK4 and/or ALK7), which then phosphorylates the Smad2 and Smad3 intracellular signaling proteins. The regulation of members of the TGF-β family is known to be complex, because many proteins able to bind the ligands and inhibit their activities have been identified. Growth and differentiation factor 11 (Gdf11) belongs to the TGF-β family. GDF11, like other members of the TGF-β superfamily, is prod…

Muscle NAD+ depletion and Serpina3n as molecular determinants of murine cancer cachexia—the effects of blocking myostatin and activins

2020

Objective Cancer cachexia and muscle loss are associated with increased morbidity and mortality. In preclinical animal models, blocking activin receptor (ACVR) ligands has improved survival and prevented muscle wasting in cancer cachexia without an effect on tumour growth. However, the underlying mechanisms are poorly understood. This study aimed to identify cancer cachexia and soluble ACVR (sACVR) administration-evoked changes in muscle proteome. Methods Healthy and C26 tumour-bearing (TB) mice were treated with recombinant sACVR. The sACVR or PBS control were administered either prior to the tumour formation or by continued administration before and after tumour formation. Muscles were an…

Activin a and matrix metalloproteinase-2 and -9 blood levels as gauges of bone metastatic spread. In: Tumor microenvironment:Heterotypic interactions.

2006

Myostatin and related proteins on the control of skeletal muscle mass and capillary density

2013

Skeletal muscle wasting is a feature of many pathological conditions such as muscular dystrophies, cancer and diabetes. Human ageing also results in the progressive loss of muscle mass and strength, a condition known as sarcopenia (or myopenia). Therefore, interventions that can reverse or slow down muscle loss are highly desirable. The TGF-β member myostatin is a well-known inhibitor of skeletal muscle growth, but it may also, if deleted, decrease muscle oxidative capacity. We have used the activin receptor 2B (ActR2B) fused to the Fc region of immunoglobulin G (ActR2B-Fc) as a trap to sequester myostatin and inhibit its activity. We sought to evaluate possible differences between doses an…

Myostatin/activin blocking combined with exercise reconditions skeletal muscle expression profile of mdx mice

2015

Duchenne Muscular Dystrophy is characterized by muscle wasting and decreased aerobic metabolism. Exercise and blocking of myostatin/activin signaling may independently or combined counteract muscle wasting and dystrophies. The effects of myostatin/activin blocking using soluble activin receptor-Fc (sActRIIB-Fc) administration and wheel running were tested alone or in combination for seven weeks in dystrophic mdx mice. Expression microarray analysis revealed decreased aerobic metabolism in the gastrocnemius muscle of mdx mice compared to healthy mice. This was not due to reduced home-cage physical activity, and was further downregulated upon sActRIIB-Fc treatment in enlarged muscles. However…

Upregulation of activin-B and follistatin in pulmonary fibrosis: a translational study using human biopsies and a specific inhibitor in mouse fibrosi…

2014

Background: Activins are members of the TGF-ß superfamily of growth factors. First, we identified by expression array screening that activin-B and follistatin are upregulated in human idiopathic pulmonary fibrosis (IPF). Next, we wanted to clarify their specific role in lung fibrosis formation. Methods: We used specific antibodies for activin-A and -B subunits and follistatin to measure and localize their levels in idiopathic pulmonary fibrosis and control lung biopsies. To inhibit activin signaling, we used soluble activin type IIB receptor fused to the Fc portion of human IgG1 (sActRIIB-Fc) in two different mouse models of pulmonary fibrosis. Results: Activin-B and follistatin mRNA levels…

Prevention of chemotherapy-induced cachexia by ACVR2B ligand blocking has different effects on heart and skeletal muscle

2017

Background Toxicity of chemotherapy on skeletal muscles and the heart may significantly contribute to cancer cachexia, mortality, and decreased quality of life. Doxorubicin (DOX) is an effective cytostatic agent, which unfortunately has toxic effects on many healthy tissues. Blocking of activin receptor type IIB (ACVR2B) ligands is an often used strategy to prevent skeletal muscle loss, but its effects on the heart are relatively unknown. Methods The effects of DOX treatment with or without pre-treatment with soluble ACVR2B-Fc (sACVR2B-Fc) were investigated. The mice were randomly assigned into one of the three groups: (1) vehicle (PBS)-treated controls, (2) DOX-treated mice (DOX), and (3) …

Combined effect of AAV-U7-induced dystrophin exon skipping and soluble activin Type IIB receptor in mdx mice.

2012

Adeno-associated virus (AAV)-U7-mediated skipping of dystrophin-exon-23 restores dystrophin expression and muscle function in the mdx mouse model of Duchenne muscular dystrophy. Soluble activin receptor IIB (sActRIIB-Fc) inhibits signaling of myostatin and homologous molecules and increases muscle mass and function of wild-type and mdx mice. We hypothesized that combined treatment with AAV-U7 and sActRIIB-Fc may synergistically improve mdx muscle function. Bioactivity of sActRIIB-Fc on skeletal muscle was first demonstrated in wild-type mice. In mdx mice we show that AAV-U7-mediated dystrophin restoration improved specific muscle force and resistance to eccentric contractions when applied a…

Mutations in SKI in Shprintzen-Goldberg syndrome lead to attenuated TGF-β responses through SKI stabilization.

2020

ABSTRACTShprintzen-Goldberg syndrome (SGS) is a multisystemic connective tissue disorder, with considerable clinical overlap with Marfan and Loeys-Dietz syndromes. These syndromes have commonly been associated with enhanced TGF-β signaling. In SGS patients, heterozygous point mutations have been mapped to the transcriptional corepressor SKI, which is a negative regulator of TGF-β signaling that is rapidly degraded upon ligand stimulation. The molecular consequences of these mutations, however, are not understood. Here we use a combination of structural biology, genome editing and biochemistry to show that SGS mutations in SKI abolish its binding to phosphorylated SMAD2 and SMAD3. This resul…

MMP-2, MMP-9 and activin A blood levels in patients with breast cancer or prostate cancer metastatic to the bone.

2007

Background: The clinical significance of the circulating levels of activin A and matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) was investigated in patients with breast cancer (BC) or prostate cancer (PC) with (M1) or without (M0) bone metastasis. Patients and Methods: MMP-2, MMP-9 and activin A blood concentrations were measured by enzyme immunoassays in 79 cancer patients and in 57 healthy blood donors (HS) who served as a control group. The diagnostic accuracy of these molecules to discriminate between M0 and M1 patients was evaluated by the receiver operating characteristic curve (ROC) and compared to that of tumor markers CA15.3 or prostate-specific antigen (PSA). Results: Activin A…