267. A role for transforming growth factor-β 1 (TGF-β1) during the establishment of folliculogenesis

2008 ◽  
Vol 20 (9) ◽  
pp. 67
Author(s):  
I. Kuyznierewicz ◽  
J. K. Findlay ◽  
A. E. Drummond

A group of structurally related proteins, known as the transforming growth factor-β (TGF- β) superfamily, have been implicated in the local regulation of ovarian function. It is unclear what role TGF-β1–3 plays in folliculogenesis during the period after birth in the rat. We investigated whether the TGF-β ligands and their receptors were present during this period of development and the effects of TGF-β1 on granulosa cell function (proliferation, apoptosis, steroidogenesis). Ovaries from rats 4, 8 and 12 days of age were isolated and RNA extracted and reverse transcribed for real-time PCR. The expression of the TGF-β ligands and TGFβRI and TGFβRII were measured. Granulosa cells isolated from DES treated immature rats were treated with FSH (100ng/mL) and TGF-β1 (1 or 10ng/mL) for 2hr, n = 4 replicates. The RNA was extracted and prepared for RT–PCR. The expression of cyclin D2, FKHR, SCC, 3βHSD and StAR were measured. TGFβRI and TGFβRII proteins were localised to postnatal rat ovary by immunohistochemistry. TGF-β1–3, TGFβRI and TGFβRII were present in rat ovaries as early as 4 days after birth. Expression of TGF-β1 mRNA increased 2-fold between day 4 and 12. TGF-β2 and TGF-β3 mRNAs declined between day 4 and 8 and remained low at day 12. The type I and II TGF-β receptors were differentially regulated with TGFβRI expression high at day 4, declining at day 8. In contrast, TGFβRII appeared to be ubiquitously expressed. Cyclin D2 mRNA expression was enhanced in the presence of both TGF-β1 and FSH, whereas FKHR mRNA expression declined. TGF-β1 had no impact on the steroidogenic mRNAs. TGFβRI and TGFβRII proteins were localised to the cytoplasm of oocytes, granulosa cells and theca cells. These studies indicate that TGF-β1 can exert effects on ovarian folliculogenesis as it is established during the postnatal period. Proliferation and apoptosis appear to be targets of TGF-β1 action. Supported by the NHMRC of Australia (Regkeys 241000, 198705, 441101 & 465415)

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Lai-Ming Yung ◽  
Samuel D Paskin-Flerlage ◽  
Ivana Nikolic ◽  
Scott Pearsall ◽  
Ravindra Kumar ◽  
...  

Introduction: Excessive Transforming Growth Factor-β (TGF-β) signaling has been implicated in pulmonary arterial hypertension (PAH), based on activation of TGF-β effectors and transcriptional targets in affected lungs and the ability of TGF-β type I receptor (ALK5) inhibitors to improve experimental PAH. However, clinical use of ALK5 inhibitors has been limited by cardiovascular toxicity. Hypothesis: We tested whether or not selective blockade of TGF-β and Growth Differentiation Factor (GDF) ligands using a recombinant TGFβ type II receptor extracellular domain Fc fusion protein (TGFBRII-Fc) could impact experimental PAH. Methods: Male SD rats were injected with monocrotaline (MCT) and received vehicle or TGFBRII-Fc (15 mg/kg, twice per week, i.p.). C57BL/6 mice were treated with SU-5416 and hypoxia (SUGEN-HX) and received vehicle or TGFBRII-Fc. RNA-Seq was used to profile transcriptional changes in lungs of MCT rats. Circulating levels of GDF-15 were measured in 241 PAH patients and 41 healthy controls. Human pulmonary artery smooth muscle cells were used to examine signaling in vitro . Results: TGFBRII-Fc is a selective ligand trap, inhibiting the ability of GDF-15, TGF-β1, TGF-β3, but not TGF-β2 to activate SMAD2/3 in vitro . In MCT rats, prophylactic treatment with TGFBRII-Fc normalized expression of TGF-β transcriptional target PAI-1, attenuated PAH and vascular remodeling. Delayed administration of TGFBRII-Fc in rats with established PAH at 2.5 weeks led to improved survival, decreased PAH and remodeling at 5 weeks. Similar findings were observed in SUGEN-HX mice. No valvular abnormalities were found with TGFBRII-Fc treatment. RNA-Seq revealed GDF-15 to be the most highly upregulated TGF-β ligand in the lungs of MCT rats, with only modest increases in TGF-β1 and no change in TGF-β2/3 observed, suggesting a dominant role of GDF-15 in the pathophysiology of this model. Plasma levels of GDF-15 were significantly increased in patients with diverse etiologies of WHO Group I PAH. Conclusions: These findings demonstrate that a selective TGF-β/GDF-15 trap attenuates experimental PAH, remodeling and mortality, without causing valvulopathy. These data highlight the potential role of GDF-15 as a pathogenic molecule and therapeutic target in PAH.


2010 ◽  
Vol 24 (3) ◽  
pp. 540-551 ◽  
Author(s):  
Guidong Yao ◽  
Mianmian Yin ◽  
Jie Lian ◽  
Hui Tian ◽  
Lin Liu ◽  
...  

Abstract Many members of the TGF-β superfamily are indicated to play important roles in ovarian follicular development, such as affecting granulosa cell function and oocyte maturation. Abnormalities associated with TGF-β1 signaling transduction could result in female infertility. MicroRNAs (miRNAs), as small noncoding RNAs, were recently found to regulate gene expression at posttranscriptional levels. However, little is known about the role of miRNAs in TGF-β-mediated granulosa cell proliferation and granulosa cell function. In this study, the miRNA expression profiling was identified from TGF-β1-treated mouse preantral granulosa cells (GCs), and three miRNAs were found to be significantly up-regulated and 13 miRNAs were down-regulated. Among up-regulated miRNAs, miR-224 was the second most significantly elevated miRNA. This up-regulation was attenuated by treatment of GCs with SB431542 (an inhibitor of TGFβ superfamily type I receptors, thus blocking phosphorylation of the downstream effectors Smad2/3), indicating that miR-224 expression was regulated by TGF-β1/Smads pathway. The ectopic expression of miR-224 can enhance TGF-β1-induced GC proliferation through targeting Smad4. Inhibition of endogenous miR-224 partially suppressed GC proliferation induced by TGF-β1. In addition, both miR-224 and TGF-β1 can promote estradiol release from GC, at least in part, through increasing CYP19A1 mRNA levels. This is the first demonstration that miRNAs can control reproductive functions resulting in promoting TGF-β1-induced GC proliferation and ovarian estrogen release. Such miRNA-mediated effects could be potentially used for regulation of reproductive processes or for treatment of reproductive disorders.


2020 ◽  
Vol 295 (36) ◽  
pp. 12559-12572
Author(s):  
Kazuki Takahashi ◽  
Yuichi Akatsu ◽  
Katarzyna A. Podyma-Inoue ◽  
Takehisa Matsumoto ◽  
Hitomi Takahashi ◽  
...  

Tumor progression is governed by various growth factors and cytokines in the tumor microenvironment (TME). Among these, transforming growth factor-β (TGF-β) is secreted by various cell types residing in the TME and promotes tumor progression by inducing the epithelial-to-mesenchymal transition (EMT) of cancer cells and tumor angiogenesis. TGF-β comprises three isoforms, TGF-β1, -β2, and -β3, and transduces intracellular signals via TGF-β type I receptor (TβRI) and TGF-β type II receptor (TβRII). For the purpose of designing ligand traps that reduce oncogenic signaling in the TME, chimeric proteins comprising the ligand-interacting ectodomains of receptors fused with the Fc portion of immunoglobulin are often used. For example, chimeric soluble TβRII (TβRII-Fc) has been developed as an effective therapeutic strategy for targeting TGF-β ligands, but several lines of evidence indicate that TβRII-Fc more effectively traps TGF-β1 and TGF-β3 than TGF-β2, whose expression is elevated in multiple cancer types. In the present study, we developed a chimeric TGF-β receptor containing both TβRI and TβRII (TβRI-TβRII-Fc) and found that TβRI-TβRII-Fc trapped all TGF-β isoforms, leading to inhibition of both the TGF-β signal and TGF-β–induced EMT of oral cancer cells, whereas TβRII-Fc failed to trap TGF-β2. Furthermore, we found that TβRI-TβRII-Fc suppresses tumor growth and angiogenesis more effectively than TβRII-Fc in a subcutaneous xenograft model of oral cancer cells with high TGF-β expression. These results suggest that TβRI-TβRII-Fc may be a promising tool for targeting all TGF-β isoforms in the TME.


2007 ◽  
Vol 75 (4) ◽  
pp. 1878-1885 ◽  
Author(s):  
Boniface Namangala ◽  
Chihiro Sugimoto ◽  
Noboru Inoue

ABSTRACT The socioeconomic implications of trypanosomosis in sub-Saharan Africa and the limitations of its current control regimes have stimulated research into alternative control methods. Considering the pro- and anti-inflammatory properties of transforming growth factor β1 (TGF-β1) and its potential to enhance immunity against protozoan parasites, we examined the effects of intraperitoneally delivered TGF-β1 in C57BL/6 mice infected with Trypanosoma congolense, the hemoprotozoan parasite causing nagana in cattle. A triple dose of 10 ng TGF-β1 significantly reduced the first parasitemic peak and delayed mortality of infected mice. Furthermore, exogenous TGF-β1 significantly decreased the development of trypanosome-induced anemia and splenomegaly. The apparent TGF-β1-induced antitrypanosome protection, occurring mainly during the early stage of infection, correlated with an enhanced parasite antigen-specific Th1 cell response characterized by a skewed type I cytokine response and a concomitant stronger antitrypanosome immunoglobulin G2a antibody response. Infected TGF-β1-pretreated mice exhibited a significant reduction in the trypanosome-induced hyperexpansion of B cells. Furthermore, evidence is provided herein that exogenous TGF-β1 activates macrophages that may contribute to parasite control. Collectively, these data indicate that exogenous TGF-β1 is immunostimulative, inducing partial protection against T. congolense infection, possibly through mechanisms involving innate immune responses.


2021 ◽  
Vol 12 ◽  
Author(s):  
Bo Zhang ◽  
Lihua Gao ◽  
Chunsheng Shao ◽  
Mingsi Deng ◽  
Liangjian Chen

Chewing areca nut (betel quid) is strongly associated with oral submucous fibrosis (OSF), a pre-cancerous lesion. Among the areca alkaloids, arecoline is the main agent responsible for fibroblast proliferation; however, the specific molecular mechanism of arecoline affecting the OSF remains unclear. The present study revealed that arecoline treatment significantly enhanced Transforming growth factor-β (TGF-β)-induced buccal mucosal fibroblast (BMF) activation and fibrotic changes. Arecoline interacts with phosphodiesterase 4A (PDE4A) to exert its effects through modulating PDE4A activity but not PDE4A expression. PDE4A silence reversed the effects of arecoline on TGF-β-induced BMFs activation and fibrotic changes. Moreover, the exchange protein directly activated by cAMP 1 (Epac1)-selective Cyclic adenosine 3′,5′-monophosphate (cAMP) analog (8-Me-cAMP) but not the protein kinase A (PKA)-selective cAMP analog (N6-cAMP) remarkably suppressed α-smooth muscle actin(α-SMA) and Collagen Type I Alpha 1 Chain (Col1A1) protein levels in response to TGF-β1 and arecoline co-treatment, indicating that cAMP-Epac1 but not cAMP-PKA signaling is involved in arecoline functions on TGF-β1-induced BMFs activation. In conclusion, arecoline promotes TGF-β1-induced BMFs activation through enhancing PDE4A activity and the cAMP-Epac1 signaling pathway during OSF. This novel mechanism might provide more powerful strategies for OSF treatment, requiring further in vivo and clinical investigation.


1998 ◽  
Vol 140 (4) ◽  
pp. 767-777 ◽  
Author(s):  
Lilach Gilboa ◽  
Rebecca G. Wells ◽  
Harvey F. Lodish ◽  
Yoav I. Henis

Abstract. Transforming growth factor β (TGF-β) signaling involves interactions of at least two different receptors, types I (TβRI) and II (TβRII), which form ligand-mediated heteromeric complexes. Although we have shown in the past that TβRII in the absence of ligand is a homodimer on the cell surface, TβRI has not been similarly investigated, and the site of complex formation is not known for either receptor. Several studies have indicated that homomeric interactions are involved in TGF-β signaling and regulation, emphasizing the importance of a detailed understanding of the homooligomerization of TβRI or TβRII. Here we have combined complementary approaches to study these homomeric interactions in both naturally expressing cell lines and cells cotransfected with various combinations of epitope-tagged type I or type II receptors. We used sedimentation velocity of metabolically labeled receptors on sucrose gradients to show that both TβRI and TβRII form homodimer-sized complexes in the endoplasmic reticulum, and we used coimmunoprecipitation studies to demonstrate the existence of type I homooligomers. Using a technique based on antibody-mediated immunofluorescence copatching of receptors carrying different epitope tags, we have demonstrated ligand-independent homodimers of TβRI on the surface of live cells. Soluble forms of both receptors are secreted as monomers, indicating that the ectodomains are not sufficient to mediate homodimerization, although TGF-β1 is able to promote dimerization of the type II receptor ectodomain. These findings may have important implications for the regulation of TGF-β signaling.


2006 ◽  
Vol 26 (12) ◽  
pp. 4577-4585 ◽  
Author(s):  
Jingmei Lin ◽  
Sanjeevkumar R. Patel ◽  
Min Wang ◽  
Gregory R. Dressler

ABSTRACT The transforming growth factor β (TGF-β) superfamily, including the bone morphogenetic protein (BMP) and TGF-β/activin A subfamilies, is regulated by secreted proteins able to sequester or present ligands to receptors. KCP is a secreted, cysteine-rich (CR) protein with similarity to mouse Chordin and Xenopus laevis Kielin. KCP is an enhancer of BMP signaling in vertebrates and interacts with BMPs and the BMP type I receptor to promote receptor-ligand interactions. Mice homozygous for a KCP null allele are hypersensitive to developing renal interstitial fibrosis, a disease stimulated by TGF-β but inhibited by BMP7. In this report, the effects of KCP on TGF-β/activin A signaling are examined. In contrast to the enhancing effect on BMPs, KCP inhibits both activin A- and TGF-β1-mediated signaling through the Smad2/3 pathway. These inhibitory effects of KCP are mediated in a paracrine manner, suggesting that direct binding of KCP to TGF-β1 or activin A can block the interactions with prospective receptors. Consistent with this inhibitory effect, primary renal epithelial cells from KCP mutant cells are hypersensitive to TGF-β and exhibit increased apoptosis, dissociation of cadherin-based cell junctions, and expression of smooth muscle actin. Furthermore, KCP null animals show elevated levels of phosphorylated Smad2 after renal injury. The ability to enhance BMP signaling while suppressing TGF-β activation indicates a critical role for KCP in modulating the responses between these anti- and profibrotic cytokines in the initiation and progression of renal interstitial fibrosis.


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