scholarly journals Regulation of ovarian function: the role of anti-Mullerian hormone

Reproduction ◽  
2002 ◽  
pp. 601-609 ◽  
Author(s):  
AL Durlinger ◽  
JA Visser ◽  
AP Themmen

Anti-Mullerian hormone (AMH), also known as Mullerian inhibiting substance, is a member of the transforming growth factor beta superfamily of growth and differentiation factors. In contrast to other members of the family, which exert a broad range of functions in multiple tissues, the principal function of AMH is to induce regression of the Mullerian ducts during male sex differentiation. However, the patterns of expression of AMH and its type II receptor in the postnatal ovary indicate that AMH may play an important role in ovarian folliculogenesis. This review describes several in vivo and in vitro studies showing that AMH participates in two critical selection points of follicle development: it inhibits the recruitment of primordial follicles into the pool of growing follicles and also decreases the responsiveness of growing follicles to FSH.

1991 ◽  
Vol 173 (5) ◽  
pp. 1121-1132 ◽  
Author(s):  
R A Fava ◽  
N J Olsen ◽  
A E Postlethwaite ◽  
K N Broadley ◽  
J M Davidson ◽  
...  

We have studied the consequences of introducing human recombinant transforming growth factor beta 1 (hrTGF-beta 1) into synovial tissue of the rat, to begin to better understand the significance of the fact that biologically active TGF-beta is found in human arthritic synovial effusions. Within 4-6 h after the intra-articular injection of 1 microgram of hrTGF-beta 1 into rat knee joints, extensive recruitment of polymorphonuclear leukocytes (PMNs) was observed. Cytochemistry and high resolution histological techniques were used to quantitate the influx of PMNs, which peaked 6 h post-injection. In a Boyden chamber assay, hrTGF-beta 1 at 1-10 fg/ml elicited a chemotactic response from PMNs greater in magnitude than that evoked by FMLP, establishing that TGF-beta 1 is an effective chemotactic agent for PMNs in vitro as well as in vivo. That PMNs may represent an important source of TGF-beta in inflammatory infiltrates was strongly suggested by a demonstration that stored TGF-beta 1 was secreted during phorbol myristate acetate-stimulated degranulation in vitro. Acid/ethanol extracts of human PMNs assayed by ELISA contained an average of 355 ng of TGF/beta 1 per 10(9) cells potentially available for secretion during degranulation of PMNs. [3H]Thymidine incorporation in vivo and autoradiography of tissue sections revealed that widespread cell proliferation was triggered by TGF-beta 1 injection. Synovial lining cells and cells located deep within the subsynovial connective tissue were identified as sources of at least some of the new cells that contribute to TGF-beta 1-induced hyperplasia. Our results demonstrate that TGF-beta is capable of exerting pathogenic effects on synovial tissue and that PMNs may represent a significant source of the TGF-beta present in synovial effusions.


2018 ◽  
Vol 9 (4) ◽  
pp. 54 ◽  
Author(s):  
Pouriska Kivanany ◽  
Kyle Grose ◽  
Nihan Yonet-Tanyeri ◽  
Sujal Manohar ◽  
Yukta Sunkara ◽  
...  

Background: Corneal stromal cells (keratocytes) are responsible for developing and maintaining normal corneal structure and transparency, and for repairing the tissue after injury. Corneal keratocytes reside between highly aligned collagen lamellae in vivo. In addition to growth factors and other soluble biochemical factors, feedback from the extracellular matrix (ECM) itself has been shown to modulate corneal keratocyte behavior. Methods: In this study, we fabricate aligned collagen substrates using a microfluidics approach and assess their impact on corneal keratocyte morphology, cytoskeletal organization, and patterning after stimulation with platelet derived growth factor (PDGF) or transforming growth factor beta 1 (TGFβ). We also use time-lapse imaging to visualize the dynamic interactions between cells and fibrillar collagen during wound repopulation following an in vitro freeze injury. Results: Significant co-alignment between keratocytes and aligned collagen fibrils was detected, and the degree of cell/ECM co-alignment further increased in the presence of PDGF or TGFβ. Freeze injury produced an area of cell death without disrupting the collagen. High magnification, time-lapse differential interference contrast (DIC) imaging allowed cell movement and subcellular interactions with the underlying collagen fibrils to be directly visualized. Conclusions: With continued development, this experimental model could be an important tool for accessing how the integration of multiple biophysical and biochemical signals regulate corneal keratocyte differentiation.


Cancers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 260 ◽  
Author(s):  
Qing Zhang ◽  
Xiaonan Hou ◽  
Bradley Evans ◽  
Jamison VanBlaricom ◽  
Saravut Weroha ◽  
...  

Transforming growth factor beta (TGF-β) signaling has pleiotropic functions regulating cancer initiation, development, and metastasis, and also plays important roles in the interaction between stromal and cancer cells, making the pathway a potential therapeutic target. LY2157299 monohydrate (LY), an inhibitor of TGF-β receptor I (TGFBRI), was examined for its ability to inhibit ovarian cancer (OC) growth both in high-grade serous ovarian cancer (HGSOC) cell lines and xenograft models. Immunohistochemistry, qRT-PCR, and Western blot were performed to study the effect of LY treatment on expression of cancer- and fibroblast-derived genes. Results showed that exposure to TGF-β1 induced phosphorylation of SMAD2 and SMAD3 in all tested OC cell lines, but this induction was suppressed by pretreatment with LY. LY alone inhibited the proliferation, migration, and invasion of HGSOC cells in vitro. TGF-β1-induced fibroblast activation was blocked by LY. LY also delayed tumor growth and suppressed ascites formation in vivo. In addition, independent of tumor inhibition, LY reduces ascites formation in vivo. Using OVCAR8 xenograft specimens we confirmed the inhibitory effect of LY on TGF-β signaling and tumor stromal expression of collagen type XI chain 1 (COL11A1) and versican (VCAN). These observations suggest a role for anti-TGF-β signaling-directed therapy in ovarian cancer.


Blood ◽  
1995 ◽  
Vol 85 (7) ◽  
pp. 1871-1880 ◽  
Author(s):  
L Flenghi ◽  
M Fagioli ◽  
L Tomassoni ◽  
S Pileri ◽  
M Gambacorta ◽  
...  

PG-M3 is a new monoclonal antibody (MoAb) specifically directed against a peptide sequence located in the aminoterminal region of the human PML protein. PML gene fuses with the retinoic acid receptor alpha (RAR alpha) gene during the t(15; 17) chromosomal translocation of acute promyelocytic leukemia (APL). The epitope recognized by PG-M3 is species-specific and fixative-resistant and is shared by most PML isoforms and PML/RAR alpha fusion proteins. PML is consistently located within the nucleus, although a minority of cells (about 20%), both in vitro and in vivo, show positivity for PML also in the cytoplasm. The nuclear staining pattern of PG-M3 varies from speckled (cells other than APL) to micropunctate (APL cells). Although two physiologically expressed PML isoforms are detectable by immunocytochemistry only or predominantly in the cytoplasm of transfected cells, the cytoplasmic localization of PML is a property also shared by the PML isoforms that predominantly localize to the nuclei. Immunohistologic analysis of normal human tissues with the PG-M3 MoAb showed variable PML expression, with the highest levels of the protein in postmitotic, differentiated cell types, such as endothelial cells, epithelia, and tissue macrophages, especially activated ones. In keeping with this in vivo finding, PML appears strongly upregulated in the U937 promonocyte cell line after exposure to agents that induce monocyte/macrophage activation (interferon gamma) or maturation (vitamin D3 and transforming growth factor beta 1).


2006 ◽  
Vol 1 (1) ◽  
pp. 43-60 ◽  
Author(s):  
Magali Cucchiarini ◽  
Jerome Sohier ◽  
Karin Mitosch ◽  
Gunter Kaul ◽  
David Zurakowski ◽  
...  

AbstractArticular cartilage repair might be stimulated by the controlled delivery of therapeutic factors. We tested the hypotheses whether TGF-ß1 can be released from a polymeric scaffold over a prolonged period of time in vitro and whether its transplantation modulates cartilage repair in vivo. Unloaded control or TGF-ß1 poly(ether-ester) copolymeric scaffolds were applied to osteochondral defects in the knee joints of rabbits. In vitro, a cumulative dose of 9 ng TGF-ß1 was released over 4 weeks. In vivo, there were no adverse effects on the synovial membrane. Defects treated with TGF-ß1 scaffolds showed no significant difference in individual parameters of chondrogenesis and in the average cartilage repair score after 3 weeks. There was a trend towards a smaller area (42.5 %) of the repair tissue that stained positive for safranin O in defects receiving TGF-ß1 scaffolds. The data indicate that TGF-ß1 is released from emulsion-coated scaffolds over a prolonged period of time in vitro and that application of these scaffolds does not significantly modulate cartilage repair after 3 weeks in vivo. Future studies need to address the importance of TGF-ß1 dose and release rate to modulate chondrogenesis.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 20044-20044
Author(s):  
W. Wick ◽  
G. Tabatabai ◽  
B. Frank ◽  
M. Weller

20044 Background: Temozolomide and irradiation are essential parts of the standard therapy and hypoxia is a critical aspect of the microenvironment of gliomas. IN the present study, we aimed at investigating the impact of these stimuli on the previously defined transforming growth factor beta (TGF-β)- and stromal cell-derived factor-1/CXC chemokine ligand 12 (SDF-1α/CXCL12)-dependent migration of adult hematopoietic stem and progenitor cells (HPC) towards glioma cells in vitro and the homing to experimental gliomas in vivo. Hyperthermia served as control. Methods and Results: Cerebral irradiation of nude mice at 21 days after intracerebral implantation of LNT-229 glioma induces tumor satellite formation and enhances the glioma tropism of HPC in vivo. Supernatants of temozolomide-treated, irradiated or hypoxic LNT-229 glioma cells promote HPC migration in vitro. Reporter assays reveal that the CXCL12 promoter activity is enhanced in LNT-229 glioma cells at 24 h after irradiation at 8 Gy or after exposure to 1% oxygen for 12 h. The irradiation- and hypoxia-induced release of CXCL12 depends on hypoxia inducible factor-1 alpha (HIF-1α), but not on p53. Induction of transcriptional activity of HIF-1α by hypoxia and irradiation requires an intact signaling cascade of TGF-β. Conclusions: Thus, we delineate a novel stress signaling cascade in glioma cells involving TGF-β, HIF-1α and CXCL12. Stress stimuli can be temozolomide, irradiation and hypoxia but not hyperthermia. These data suggest that the use of HPC as cellular vectors in the treatment of glioblastoma may well be combined with anti-angiogenic therapies which induce tumor hypoxia. [Table: see text]


2017 ◽  
Vol 204 (3-4) ◽  
pp. 191-198 ◽  
Author(s):  
Gemma A. Figtree ◽  
Kristen J. Bubb ◽  
Owen Tang ◽  
Eddy Kizana ◽  
Carmine Gentile

Spheroid cultures are among the most explored cellular biomaterials used in cardiovascular research, due to their improved integration of biochemical and physiological features of the heart in a defined architectural three-dimensional microenvironment when compared to monolayer cultures. To further explore the potential use of spheroid cultures for research, we engineered a novel in vitro model of the heart with vascularized cardiac spheroids (VCSs), by coculturing cardiac myocytes, endothelial cells, and fibroblasts isolated from dissociated rat neonatal hearts (aged 1-3 days) in hanging drop cultures. To evaluate the validity of VCSs in recapitulating pathophysiological processes typical of the in vivo heart, such as cardiac fibrosis, we then treated VCSs with transforming growth factor beta 1 (TGFβ1), a known profibrotic agent. Our mRNA analysis demonstrated that TGFβ1-treated VCSs present elevated levels of expression of connective tissue growth factor, fibronectin, and TGFβ1 when compared to control cultures. We demonstrated a dramatic increase in collagen deposition following TGFβ1 treatment in VCSs in the PicroSirius Red-stained sections. Doxorubicin, a renowned cardiotoxic and profibrotic agent, triggered apoptosis and disrupted vascular networks in VCSs. Taken together, our findings demonstrate that VCSs are a valid model for the study of the mechanisms involved in cardiac fibrosis, with the potential to be used to investigate novel mechanisms and therapeutics for treating and preventing cardiac fibrosis in vitro.


1997 ◽  
Vol 17 (8) ◽  
pp. 4338-4345 ◽  
Author(s):  
P Saha ◽  
Q Eichbaum ◽  
E D Silberman ◽  
B J Mayer ◽  
A Dutta

Cdc25A, a phosphatase essential for G1-S transition, associates with, dephosphorylates, and activates the cell cycle kinase cyclin E-cdk2. p21CIP1 and p27 are cyclin-dependent kinase (cdk) inhibitors induced by growth-suppressive signals such as p53 and transforming growth factor beta (TGF-beta). We have identified a cyclin binding motif near the N terminus of Cdc25A that is similar to the cyclin binding Cy (or RR LFG) motif of the p21CIP1 family of cdk inhibitors and separate from the catalytic domain. Mutations in this motif disrupt the association of Cdc25A with cyclin E- or cyclin A-cdk2 in vitro and in vivo and selectively interfere with the dephosphorylation of cyclin E-cdk2. A peptide based on the Cy motif of p21 competitively disrupts the association of Cdc25A with cyclin-cdks and inhibits the dephosphorylation of the kinase. p21 inhibits Cdc25A-cyclin-cdk2 association and the dephosphorylation of cdk2. Conversely, Cdc25A, which is itself an oncogene up-regulated by the Myc oncogene, associates with cyclin-cdk and protects it from inhibition by p21. Cdc25A also protects DNA replication in Xenopus egg extracts from inhibition by p21. These results describe a mechanism by which the Myc- or Cdc25A-induced oncogenic and p53- or TGF-beta-induced growth-suppressive pathways counterbalance each other by competing for cyclin-cdks.


1991 ◽  
Vol 174 (3) ◽  
pp. 539-545 ◽  
Author(s):  
J S Silva ◽  
D R Twardzik ◽  
S G Reed

The effects of transforming growth factor beta (TGF-beta) on interferon gamma-mediated killing of the intracellular protozoan parasite Trypanosoma cruzi and on the course of T. cruzi infection in mice were investigated. Spleen cells from mice with acute T. cruzi infections were found to produce elevated levels of biologically active TGF-beta in vitro, and the possibility that TGF-beta may mediate certain aspects of T. cruzi infection was then addressed. When mouse peritoneal macrophages were treated with TGF-beta in vitro, the ability of IFN-gamma to activate intracellular inhibition of the parasite was blocked. This occurred whether cells were treated with TGF-beta either before or after IFN-gamma treatment. TGF-beta treatment also blocked the T. cruzi-inhibiting effects of IGN-gamma on human macrophages. Additionally, treatment of human macrophages with TGF-beta alone led to increased parasite replication in these cells. The effects of TGF-beta on T. cruzi infection in vivo were then investigated. Susceptible C57BL/6 mice developed higher parasitemias and died earlier when treated with TGF-beta during the course of infection. Resistant C57BL/6 x DBA/2 F1 mice treated with TGF-beta also had increased parasitemias, and 50% mortality, compared with no mortality in infected, saline-treated controls. A single dose of TGF-beta, given at the time of infection, was sufficient to significantly decrease resistance to infection in F1 mice and to exacerbate infection in susceptible C57BL/6 mice. Furthermore, a single injection of TGF-beta was sufficient to counter the in vivo protective effects of IFN-gamma. We conclude that TGF-beta, produced during acute T. cruzi infection in mice, is a potent inhibitor of the effects of macrophage activating cytokines in vivo and in vitro and may play a role in regulating infection.


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