scholarly journals The gp130 Cytokines Interleukin-11 and Ciliary Neurotropic Factor Regulate through Specific Receptors the Function and Growth of Lactosomatotropic and Folliculostellate Pituitary Cell Lines*

Endocrinology ◽  
2000 ◽  
Vol 141 (5) ◽  
pp. 1746-1753 ◽  
Author(s):  
Carolina Perez Castro ◽  
Alberto Carbia Nagashima ◽  
Marcelo Páez Pereda ◽  
Victoria Goldberg ◽  
Alberto Chervin ◽  
...  

Abstract Two of the most potent cytokines regulating anterior pituitary cell function are leukemia inhibitory factor and interleukin-6 (IL-6), which belong to the cytokine receptor family using the common gp130 signal transducer. We studied the actions of two other members of this family, IL-11 and ciliary neurotropic factor (CNTF), on folliculostellate (FS) cells (TtT/GF cell line) and lactosomatotropic cells (GH3 cell line). The messenger RNA (mRNA) for the α-chain specific for the IL-11 receptor (1.7 kb) and CNTF receptor (2 kb) are expressed on both cell types. In addition, we detected CNTF receptor mRNA in normal rat anterior pituitary cells. IL-11 (1.25–5 nm) dose dependently stimulated the proliferation of FS cells. CNTF, at doses from 0.4–2 nm, also significantly stimulated the growth of these cells. In addition, both cytokines significantly stimulated proliferation of lactosomatotropic GH3 cells, and CNTF stimulated hormone production (GH and PRL) at 24 h by these cells. At 16–72 h, IL-11 stimulates the secretion of the angiogenic factor vascular endothelial growth factor by FS cells. In addition, both GH3 and FS cells express CNTF mRNA. These data suggest that IL-11 and CNTF may act as growth and regulatory factors in anterior pituitary cells.

2006 ◽  
Vol 189 (3) ◽  
pp. 681-690 ◽  
Author(s):  
M Candolfi ◽  
G Jaita ◽  
D Pisera ◽  
L Ferrari ◽  
C Barcia ◽  
...  

Our previous work showed that tumor necrosis factor (TNF)-α and FasL induce apoptosis of anterior pituitary cells. To further analyze the effect of these proapoptotic factors, we infected primary cultures from rat anterior pituitary, GH3 and AtT20 cells with first-generation adenoviral vectors encoding TNF-α, FasL or, as a control, β-galactosidase (β-Gal), under the control of the human cytomegalovirus promoter. Successful expression of the encoded transgenes was determined by immunocytochemistry. Although we observed basal expression of TNF-α and FasL in control cultures of anterior pituitary cells, fluorescence-activated cell sorting (FACS) cell cycle analysis showed that the overexpression of TNF-α or FasL increases the percentage of hypodiploid lactotropes and somatotropes. Nuclear morphology and TUNEL staining revealed that the cells undergo an apoptotic death process. We detected strong immunoreactivity for TNFR1 and Fas in the somatolactotrope cell line GH3. TNF-α, but not FasL, was expressed in control cultures of GH3 cells. The infection of GH3 cells with adenovirus encoding TNF-α or FasL increased the percentages of hypodiploid and TUNEL-positive cells. TNF-α or FasL immunoreactivity was not observed in the corticotrope cell line AtT20. However, adenovirus encoding TNF-α or FasL efficiently transduced these cells and increased the percentages of hypodiploid and TUNEL-positive cells. The expression of β-Gal was detected in all these cultures but did not affect cell viability. In conclusion, these results suggest that death signaling cascades triggered by TNF receptor 1 (TNFR1) and Fas are present in both normal and tumoral pituitary cells. Therefore, overexpression of proapoptotic factors could be a useful tool in the therapy of pituitary adenomas.


1988 ◽  
Vol 139 (1) ◽  
pp. 287-316
Author(s):  
W. T. Mason ◽  
S. R. Rawlings ◽  
P. Cobbett ◽  
S. K. Sikdar ◽  
R. Zorec ◽  
...  

Normal anterior pituitary cells, in their diversity and heterogeneity, provide a rich source of models for secretory function. However, until recently they have largely been neglected in favour of neoplastic, clonal tumour cell lines of pituitary origin, which have enabled a number of studies on supposedly homogeneous cell types. Because many of these lines appear to lack key peptide and neurotransmitter receptors, as well as being degranulated with accompanying abnormal levels of secretion, we have developed a range of normal primary anterior pituitary cell cultures using dispersion and enrichment techniques. By studying lactotrophs, somatotrophs and gonadotrophs we have revealed a number of possible transduction mechanisms by which receptors for hypothalamic peptides and neurotransmitters may control secretion. In particular, the transduction events controlling secretion from pituitary cells may differ fundamentally from those found in other cell types. Patch-clamp recordings in these various pituitary cell preparations have revealed substantial populations of voltage-dependent Na+, Ca2+ and K+ channels which may support action potentials in these cells. Although activation of these channels may gate Ca2+ entry to the cells under some conditions, our evidence taken with that of other laboratories suggests that peptide-receptor interactions leading to hormone secretion occur independently of significant membrane depolarization. Rather, secretion of hormone and rises in intracellular calcium measured with new probes for intracellular calcium activity, can occur in response to hypothalamic peptide activation in the absence of substantial changes in membrane potential. These changes in intracellular calcium activity almost certainly depend on both intracellular and extracellular calcium sources. In addition, strong evidence of a role for multiple intracellular receptors and modulators in the secretory event suggests we should consider the plasma membrane channels important for regulation of hormone secretion to be predominantly agonist-activated, rather than of the more conventional voltage-dependent type. Likewise, evidence from new methods for recording single ion channels suggests the existence of intracellular sites for channel modulation, implying they too may play an important role in secretory regulation. We shall consider new data and new technology which we hope will provide key answers to the many intriguing questions surrounding the control of pituitary hormone secretion. We shall highlight our work with recordings of single ion channels activated by peptides, and recent experiments using imaging of intracellular ionized free calcium.(ABSTRACT TRUNCATED AT 250 WORDS)


2001 ◽  
Vol 15 (6) ◽  
pp. 1010-1022 ◽  
Author(s):  
Tatjana S. Kostic ◽  
Silvana A. Andric ◽  
Stanko S. Stojilkovic

Abstract Nitric oxide (NO)-dependent soluble guanylyl cyclase (sGC) is operative in mammalian cells, but its presence and the role in cGMP production in pituitary cells have been incompletely characterized. Here we show that sGC is expressed in pituitary tissue and dispersed cells, enriched lactotrophs and somatotrophs, and GH3 immortalized cells, and that this enzyme is exclusively responsible for cGMP production in unstimulated cells. Basal sGC activity was partially dependent on voltage-gated calcium influx, and both calcium-sensitive NO synthases (NOS), neuronal and endothelial, were expressed in pituitary tissue and mixed cells, enriched lactotrophs and somatotrophs, and GH3 cells. Calcium-independent inducible NOS was transiently expressed in cultured lactotrophs and somatotrophs after the dispersion of cells, but not in GH3 cells and pituitary tissue. This enzyme participated in the control of basal sGC activity in cultured pituitary cells. The overexpression of inducible NOS by lipopolysaccharide + interferon-γ further increased NO and cGMP levels, and the majority of de novo produced cGMP was rapidly released. Addition of an NO donor to perifused pituitary cells also led to a rapid cGMP release. Calcium-mobilizing agonists TRH and GnRH slightly increased basal cGMP production, but only when added in high concentrations. In contrast, adenylyl cyclase agonists GHRH and CRF induced a robust increase in cGMP production, with EC50s in the physiological concentration range. As in cells overexpressing inducible NOS, the stimulatory action of GHRH and CRF was preserved in cells bathed in calcium-deficient medium, but was not associated with a measurable increase in NO production. These results indicate that sGC is present in secretory anterior pituitary cells and is regulated in an NO-dependent manner through constitutively expressed neuronal and endothelial NOS and transiently expressed inducible NOS, as well as independently of NO by adenylyl cyclase coupled-receptors.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Frederique Murielle Ruf-Zamojski ◽  
Michel A Zamojski ◽  
German Nudelman ◽  
Yongchao Ge ◽  
Natalia Mendelev ◽  
...  

Abstract The pituitary gland is a critical regulator of the neuroendocrine system. To further our understanding of the classification, cellular heterogeneity, and regulatory landscape of pituitary cell types, we performed and computationally integrated single cell (SC)/single nucleus (SN) resolution experiments capturing RNA expression, chromatin accessibility, and DNA methylation state from mouse dissociated whole pituitaries. Both SC and SN transcriptome analysis and promoter accessibility identified the five classical hormone-producing cell types (somatotropes, gonadotropes (GT), lactotropes, thyrotropes, and corticotropes). GT cells distinctively expressed transcripts for Cga, Fshb, Lhb, Nr5a1, and Gnrhr in SC RNA-seq and SN RNA-seq. This was matched in SN ATAC-seq with GTs specifically showing open chromatin at the promoter regions for the same genes. Similarly, the other classically defined anterior pituitary cells displayed transcript expression and chromatin accessibility patterns characteristic of their own cell type. This integrated analysis identified additional cell-types, such as a stem cell cluster expressing transcripts for Sox2, Sox9, Mia, and Rbpms, and a broadly accessible chromatin state. In addition, we performed bulk ATAC-seq in the LβT2b gonadotrope-like cell line. While the FSHB promoter region was closed in the cell line, we identified a region upstream of Fshb that became accessible by the synergistic actions of GnRH and activin A, and that corresponded to a conserved region identified by a polycystic ovary syndrome (PCOS) single nucleotide polymorphism (SNP). Although this locus appears closed in deep sequencing bulk ATAC-seq of dissociated mouse pituitary cells, SN ATAC-seq of the same preparation showed that this site was specifically open in mouse GT, but closed in 14 other pituitary cell type clusters. This discrepancy highlighted the detection limit of a bulk ATAC-seq experiment in a subpopulation, as GT represented ~5% of this dissociated anterior pituitary sample. These results identified this locus as a candidate for explaining the dual dependence of Fshb expression on GnRH and activin/TGFβ signaling, and potential new evidence for upstream regulation of Fshb. The pituitary epigenetic landscape provides a resource for improved cell type identification and for the investigation of the regulatory mechanisms driving cell-to-cell heterogeneity. Additional authors not listed due to abstract submission restrictions: N. Seenarine, M. Amper, N. Jain (ISMMS).


1985 ◽  
Vol 248 (1) ◽  
pp. E15-E19
Author(s):  
I. S. Login ◽  
A. M. Judd ◽  
M. J. Cronin ◽  
T. Yasumoto ◽  
R. M. MacLeod

Reserpine exerts direct effects on several tissues, including inhibition of hormone release from rat anterior pituitary cells. To test the hypothesis that reserpine may be acting as a calcium channel antagonist, normal or GH3 rat anterior pituitary cells were preincubated in reserpine or the conventional calcium channel blocker, D-600, followed by exposure to 45Ca2+ together with stimulants of calcium uptake: maitotoxin, a potent calcium channel activator; A23187, a calcium ionophore; or 50 mMK+. After incubation, the cells were harvested by vacuum filtration and cell-associated radioactivity determined. In normal cells, reserpine blocked both basal and K+-stimulated calcium uptake. Reserpine selectively blocked maitotoxin but not A23187-induced calcium uptake. In GH3 cells 9 microM reserpine and 30 microM D-600 were equally effective in blocking maitotoxin-stimulated calcium uptake. Reserpine appears to block voltage-dependent calcium channels in pituitary cells in a concentration-dependent manner but not calcium uptake caused nonspecifically by A23187.


1999 ◽  
Vol 84 (8) ◽  
pp. 2903-2911 ◽  
Author(s):  
Long Jin ◽  
Bartolome G. Burguera ◽  
Marta E. Couce ◽  
Bernd W. Scheithauer ◽  
Jesse Lamsan ◽  
...  

Leptin is a circulating hormone secreted by adipose and a few other tissues. The leptin receptor consists of a single transmembrane-spanning polypeptide that is present as a long physiologically important form as well as in several short isoforms. Recent studies have suggested that the anterior pituitary may have a role in the regulatory effects of leptin in animal models. To test this possibility in human pituitaries, we examined the expression of leptin and OB-R in normal and neoplastic pituitaries, and the possible functions of leptin in the pituitary were also analyzed. Leptin was present in 20–25% of anterior pituitary cells and was expressed in most normal anterior pituitary cells, including ACTH (70% of ACTH cells), GH (21%), FSH (33%), LH (29%), TSH (32%), and folliculo-stellate cells (64%), but was colocalized with very few PRL cells (3%), as detected by double labeling immunohistochemistry with two different antileptin antibodies. In addition, leptin expression was detected by RT-PCR in some pituitary tumors, including ACTH (three of four), GH (one of four), null cells (two of four), and gonadotroph (one of four) tumors as well as in normal pituitary. Immunohistochemical staining showed greater immunoreactivity for leptin in normal pituitaries compared to adenomas. Treatment of an immortalized cultured anterior pituitary cell line, HP75, with leptin stimulated pancreastatin secretion in vitro. Leptin also inhibited cell growth in the human HP75 and in the rat pituitary GH3 cell lines. Both long (OB-Rb) and common (OB-Ra) forms of the leptin receptor messenger ribonucleic acid and leptin receptor protein were expressed in normal and neoplastic anterior pituitary cells. These findings show for the first time that leptin is expressed by most human anterior pituitary cell types and that there is decreased leptin protein immunoreactivity in pituitary adenomas compared to that in normal pituitary tissues. We also show that OB-Rb is widely expressed by normal and neoplastic anterior pituitary cells, implicating an autocrine/paracrine loop in the production and regulation of leptin in the pituitary.


1994 ◽  
Vol 142 (1) ◽  
pp. 9-18 ◽  
Author(s):  
S E Mau ◽  
M R Witt ◽  
H Vilhardt

Abstract Studies have shown that mastoparan and other amphiphilic peptides induce exocytosis of hormones from anterior pituitary cells. We have studied the effect of mastoparan on the secretion of prolactin from cultured rat anterior pituitary cells and on the concomitant functional status of signal-transducing pathways in lactotroph-enriched cell cultures. Mastoparan stimulation of prolactin secretion was dose-dependent, time-dependent, reversible and required the presence of calcium. Pretreatment of pituitary cell cultures with cholera and pertussis toxin had no effect on the secretory response, whereas encapsulation of guanosine 5-[β-thio]diphosphate (GDP-β-S) by reversible electropermeabilization inhibited mastoparan-stimulated secretion. Incubation of mastoparan with myo[3H]inositol-labelled lactotroph-enriched anterior pituitary cell cultures resulted in increased formation of inositol phosphates compared with control cells, and encapsulation of GDP-β-S blocked mastoparan-induced inositol lipid hydrolysis. Mastoparan caused translocation of protein kinase C activity from a soluble to a membrane-attached form. Mastoparan was able to increase the intracellular Ca2+ concentration in Fura-2-loaded individual lactotrophs. Omission of Ca2+ from the extracellular medium did not change the Ca2+ response in lactotrophs when stimulated with mastoparan. On the basis of these results it is concluded that mastoparan-induced release of prolactin is preceded by activation of the inositol(1,4,5)trisphosphate/diacylglycerol pathway with resulting translocation of protein kinase activity and increment in intracellular Ca2+. However, other signal-transducing pathways may be involved in the secretory process. Journal of Endocrinology (1994) 142, 9–18


PLoS ONE ◽  
2019 ◽  
Vol 14 (9) ◽  
pp. e0222340 ◽  
Author(s):  
Ze-Wen Yu ◽  
Wei Gao ◽  
Xin-Yao Feng ◽  
Jin-Yu Zhang ◽  
Hai-Xiang Guo ◽  
...  

2019 ◽  
Vol 3 (11) ◽  
pp. 1969-1978 ◽  
Author(s):  
Keitaro Kanie ◽  
Hironori Bando ◽  
Genzo Iguchi ◽  
Keiko Muguruma ◽  
Ryusaku Matsumoto ◽  
...  

Abstract Context Anti–pituitary-specific transcriptional factor-1 (anti–PIT-1) antibody syndrome is characterized by acquired and specific deficiencies in growth hormone, prolactin, and thyroid-stimulating hormone. Although PIT-1–reactive cytotoxic T lymphocytes (CTLs) have been speculated to recognize anterior pituitary cells and to cause the injury in the pathogenesis of the syndrome, it remains unclear whether endogenous PIT-1 protein is processed through the proteolytic pathway and presented as an antigen on anterior pituitary cells. Objective To examine how PIT-1 protein is processed and whether its epitope is presented by major histocompatibility complex (MHC)/HLA class I on anterior pituitary cells. Materials and Methods Immunofluorescence staining and proximity ligation assay (PLA) were performed using anti–PIT-1 antibody and patients’ sera on PIT-1–expressing cell line GH3 cells and human induced pluripotent stem cell (iPSC)-derived pituitary tissues. Results PIT-1 was colocalized with MHC class I molecules, calnexin, and GM130 in the cytosol. PLA results showed that PIT-1 epitope was presented by MHC/HLA class I molecules on the cell surface of GH3 cells and iPSC-derived pituitary cells. The number of PIT-1/HLA complexes on the cell surface of pituitary cells in the patient was comparable with that in the control subject. Conclusions Our data indicate that PIT-1 protein is processed in the antigen presentation pathway and that its epitopes are presented by in MHC/HLA class I on anterior pituitary cells, supporting the hypothesis that PIT-1–reactive CTLs caused the cell-specific damage. It is also suggested that number of epitope presentation was not associated with the pathogenesis of anti–PIT-1 antibody syndrome.


Peptides ◽  
1993 ◽  
Vol 14 (3) ◽  
pp. 647-649 ◽  
Author(s):  
Toshikazu Kuwahara ◽  
Mari Takamiya ◽  
Hiromi Nagase ◽  
Tsutomu Kudoh ◽  
Atsuko Nakano ◽  
...  

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