scholarly journals Expression of activin A and its receptors in human pheochromocytomas

2000 ◽  
Vol 165 (2) ◽  
pp. 503-508 ◽  
Author(s):  
J Liu ◽  
P Heikkila ◽  
AI Kahri ◽  
R Voutilainen
Keyword(s):  
Protein Kinase ◽  
Mrna Expression ◽  
Kinase Inhibitor ◽  
Receptor Gene ◽  
Primary Cultures ◽  
Activin A ◽  
Enzyme Linked Immunosorbent Assay ◽  
Type I ◽  
Pheochromocytoma Cells

Activin A (a homodimer of two activin betaA subunits) has been shown to induce the neuronal differentiation of rat pheochromocytoma PC12 cells. We studied activin A and its receptor gene expression in human pheochromocytomas in vivo and in vitro to clarify the potential involvement of activin A in the pathophysiology of these tumors. We first screened 20 pheochromocytomas and nine normal adrenal tissues for activin betaA mRNA expression. Northern blots hybridized with specific oligonucleotide probes detected weak signals for activin betaA transcripts in pheochromocytomas. Both type I and type II activin receptor (ActR-I, ActR-IB and ActR-II) mRNA expression was also detectable in the pheochromocytoma tissues. In primary cultures of pheochromocytoma cells, expression of activin betaA mRNA was readily detectable by Northern blotting, and secretion of activin A into the conditioned medium was confirmed by an enzyme-linked immunosorbent assay. The expression of activin betaA mRNA and secretion of activin A were induced by (Bu)(2)cAMP after 1 and 3 days of treatment (all P<0.05). A protein kinase inhibitor, staurosporine, inhibited the basal and (Bu)(2)cAMP-induced accumulation of activin betaA mRNA (P<0.05). In addition, induction of chromaffin phenotype by dexamethasone also inhibited the basal and (Bu)(2)cAMP-induced expression of activin A at both mRNA and protein levels (all P<0.05). In contrast, the expression of ActR-I and ActR-IB mRNAs was not affected by these agents in cultured pheochromocytoma cells. In summary, activin betaA subunit and activin receptors are expressed in human pheochromocytomas. Production of activin A in cultured pheochromocytoma cells is induced through the protein kinase A pathway, but reduced during chromaffin differentiation. Therefore, activin A may function as a local neurotrophic factor via an auto/paracrine manner in human pheochromocytomas.

scholarly journals The localisation and expression of 5 alpha-reductase types I and II mRNAs in human hyperplastic prostate and in prostate primary cultures

1998 ◽  
Vol 156 (3) ◽  
pp. 509-517 ◽  
Author(s):  
FK Habib ◽  
M Ross ◽  
CW Bayne ◽  
K Grigor ◽  
AC Buck ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Mrna Expression ◽  
Primary Cultures ◽  
Secretory Cells ◽  
Enzyme Assays ◽  
Type I ◽  
Rt Pcr ◽  
Stromal Component ◽  
Hyperplastic Tissue

The expression and localisation of mRNAs for 5 alpha reductase Type I (5 alpha R-I) and Type II (5 alpha R-II) isoenzymes in human benign prostatic hyperplasia (BPH) were investigated by RT-PCR and by in mini hybridisation (ISH) using digoxigenin labelled riboprobes. In addition, we also examined the isoenzymes mRNA expression in primary BPH cultures of separated stroma/fibroblast and epithelial cells to determine whether primary cultures are appropriate models in which to investigate 5 alpha R activity and regulation. The results demonstrated conclusively the presence of mRNA encoding both isoenzymes in all specimens so far examined. Additionally, the presence of a functional 5 alpha R-I and -II activity in BPH was confirmed by enzyme assays. ISH studies localised the mRNA expression to both the fibroblast/stromal component as well as the epithelial cells of the hyperplastic tissue. In the glandular regions the expression for both isoenzymes was particularly strong in the basal layers of the epithelium whereas mRNA expression in the secretory cells was less pronounced. Expression of 5 alpha R-I and -II mRNAs in fibroblast was on the other hand variable with high expression in some areas and little in others. These findings were supported by our primary culture experiments which demonstrated that both the fibroblast and epithelial cells maintain a capacity to express both isoenzymes in vitro. In the case of the fibroblast, the capacity to express the isoenzymes was maintained following the sequential passaging of the cells up to passage 6, after which the cells no longer expressed either isoenzyme.

scholarly journals cGMP inhibition of type 3 phosphodiesterase is the major mechanism by which C-type natriuretic peptide activates CFTR in the shark rectal gland

2014 ◽  
Vol 306 (4) ◽  
pp. C343-C353 ◽  
Author(s):  
Hugo R. De Jonge ◽  
Ben C. Tilly ◽  
Boris M. Hogema ◽  
Daniel J. Pfau ◽  
Catherine A. Kelley ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Epithelial Cells ◽  
Natriuretic Peptide ◽  
Kinase Inhibitor ◽  
Basolateral Membrane ◽  
Primary Cultures ◽  
Chloride Secretion ◽  
Rectal Gland ◽  
Type I ◽  
Shark Rectal Gland

The in vitro perfused rectal gland of the dogfish shark ( Squalus acanthias) and filter-grown monolayers of primary cultures of shark rectal gland (SRG) epithelial cells were used to analyze the signal transduction pathway by which C-type natriuretic peptide (CNP) stimulates chloride secretion. CNP binds to natriuretic receptors in the basolateral membrane, elevates cellular cGMP, and opens cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels in the apical membrane. CNP-provoked chloride secretion was completely inhibitable by the nonspecific protein kinase inhibitor staurosporine and the PKA inhibitor H89 but insensitive to H8, an inhibitor of type I and II isoforms of cGMP-dependent protein kinase (cGKI and cGKII). CNP-induced secretion could not be mimicked by nonhydrolyzable cGMP analogs added alone or in combination with the protein kinase C activator phorbolester, arguing against a role for cGK or for cGMP-induced PKC signaling. We failed to detect a dogfish ortholog of cGKII by molecular cloning and affinity chromatography. However, inhibitors of the cGMP-inhibitable isoform of phosphodiesterase (PDE3) including milrinone, amrinone, and cilostamide but not inhibitors of other PDE isoenzymes mimicked the effect of CNP on chloride secretion in perfused glands and monolayers. CNP raised cGMP and cAMP levels in the SRG epithelial cells. This rise in cAMP as well as the CNP and amrinone-provoked chloride secretion, but not the rise in cGMP, was almost completely blocked by the Gαi-coupled adenylyl cyclase inhibitor somatostatin, arguing against a role for cGMP cross-activation of PKA in CNP action. These data provide molecular, functional, and pharmacological evidence for a CNP/cGMP/PDE3/cAMP/PKA signaling cascade coupled to CFTR in the SRG.

scholarly journals Evidence for the interleukin-2 dependent expansion of leukemic cells in adult T cell leukemia

Blood ◽  
1987 ◽  
Vol 70 (5) ◽  
pp. 1407-1411 ◽  
Author(s):  
M Maeda ◽  
N Arima ◽  
Y Daitoku ◽  
M Kashihara ◽  
H Okamoto ◽  
...  
Keyword(s):  
T Cell ◽  
Receptor Gene ◽  
Interleukin 2 ◽  
Leukemic Cells ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
In Vitro Proliferation ◽  
Adult T Cell Leukemia

Abstract Interleukin 2 (IL-2) receptor/Tac antigen is abnormally expressed on cells of patients with adult T cell leukemia (ATL) caused by infection with human T lymphotropic virus type I (HTLV-I). Twenty-five patients with ATL were examined to determine whether their leukemic cells continued to show IL-2-dependent proliferation. In 21 patients, the in vitro proliferation of HTLV-I-infected nonleukemic T cell clones was found to be dependent on IL-2. However, clonality analysis based on T cell receptor gene rearrangement profiles and the site of HTLV-I provirus integration revealed IL-2-dependent growth in leukemic cells in four patients with ATL. These results provide evidence for the IL-2- dependent proliferation of leukemic cells in some ATL patients.

scholarly journals In vitro phosphorylation of type I collagen by cyclic AMP-dependent protein kinase.

1986 ◽  
Vol 261 (12) ◽  
pp. 5674-5679
Author(s):  
D B Glass ◽  
J M McPherson
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Type I Collagen ◽  
Type I ◽  
Dependent Protein Kinase ◽  
Dependent Protein

scholarly journals 14 Characterization of adipose tissue extracellular matrix component mRNA expression during porcine adipogenesis using real-time PCR

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 35-35
Author(s):  
Maegan A Reeves ◽  
Courtney E Charlton ◽  
Terry D Brandebourg
Keyword(s):  
Extracellular Matrix ◽  
Adipose Tissue ◽  
Mrna Expression ◽  
Real Time ◽  
Real Time Pcr ◽  
Collagen Type ◽  
Primary Cultures ◽  
Collagen Type I ◽  
Type I ◽  
Matrix Metallopeptidase

Abstract Given adipose tissue is histologically classified as connective tissue, we hypothesized expression of extracellular matrix (ECM) components are significantly altered during adipogenesis. However, little is known about the regulation of the ECM during adipose tissue development in the pig. Therefore, the objective of this study was to characterize expression of ECM components during porcine adipogenesis. Primary cultures of adipose tissue stromal-vascular cells were harvested from 3-day-old neonatal pigs (n=6) and preadipocytes induced to differentiate in vitro for 8 days in the presence of insulin, hydrocortisone, and rosiglitazone. Total RNA was extracted from these cultures on days 0 and 8 post-induction. Real-time PCR was then utilized to determine changes in mRNA expression for collagen type I alpha 1 chain (COL1A), collagen type I alpha 2 chain (COL2A), collagen type I alpha 3 chain (COL3A), collagen type I alpha 4 chain (COL4A), collagen type I alpha 6 chain (COL6A), biglycan, fibronectin, laminin, nitogen-1 (NID1), matrix metallopeptidase 2 (MMP2), matrix metallopeptidase 9 (MMP9), metallopeptidase inhibitor 3 (TIMP3). The mRNA abundances of COL1A, COL3A and MMP2 were significantly downregulated 2.86-fold (P &lt; 0.05), 16.7-fold (P &lt; 0.01) and 3.1-fold (P &lt; 0.05) respectively in day 8 (differentiated) compared to day 0 (undifferentiated) cultures. Meanwhile, mRNA abundances were significantly upregulated during adipogenesis for the COL2A (2.82-fold; P &lt; 0.05), COL4A (2.01-fold; P &lt; 0.05), COL6A (2.8-fold; P &lt; 0.05), biglycan (49.9- fold; P &lt; 0.001), fibronectin (452-fold; P &lt; 0.001), laminin (6.1-fold; P &lt; 0.05), NID1(47.4-fold; P &lt; 0.01), MMP9 (76.8- fold; P &lt; 0.01), and TIMP3(3.04-fold; P &lt; 0.05) genes. These data support the hypothesis that significant changes in ECM components occur during porcine adipogenesis. Modulating adipose tissue ECM remodeling might be a novel strategy to manipulate adiposity in the pig.

scholarly journals Anti-echinococcal effect of verapamil involving the regulation of the calcium/calmodulin-dependent protein kinase II response in vitro and in a murine infection model

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Hai-Jun Gao ◽  
Xu-Dong Sun ◽  
Yan-Ping Luo ◽  
Hua-Sheng Pang ◽  
Xing-Ming Ma ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Mrna Expression ◽  
Echinococcus Granulosus ◽  
Calcium Content ◽  
Mrna Levels ◽  
Dependent Protein Kinase ◽  
Calcium Calmodulin Dependent ◽  
Dependent Protein

Abstract Background Echinococcosis, which is caused by the larvae of cestodes of the genus Echinococcus, is a parasitic zoonosis that poses a serious threat to the health of humans and animals globally. Albendazole is the drug of choice for the treatment of echinococcosis, but it is difficult to meet clinical goals with this chemotherapy due to its low cure rate and associated side effects after its long-term use. Hence, novel anti-parasitic targets and effective treatment alternatives are urgently needed. A previous study showed that verapamil (Vepm) can suppress the growth of Echinococcus granulosus larvae; however, the mechanism of this effect remains unclear. The aim of the present study was to gain insight into the anti-echinococcal effect of Vepm on Echinococcus with a particular focus on the regulatory effect of Vepm on calcium/calmodulin-dependent protein kinase II (Ca2+/CaM-CaMKII) in infected mice. Methods The anti-echinococcal effects of Vepm on Echinococcus granulosus protoscoleces (PSC) in vitro and Echinococcus multilocularis metacestodes in infected mice were assessed. The morphological alterations in Echinococcus spp. induced by Vepm were observed by scanning electron microscopy (SEM), and the changes in calcium content in both the parasite and mouse serum and liver were measured by SEM-energy dispersive spectrometry, inductively coupled plasma mass spectrometry and alizarin red staining. Additionally, the changes in the protein and mRNA levels of CaM and CaMKII in infected mice, and in the mRNA levels of CaMKII in E. granulosus PSC, were evaluated after treatment with Vepm by immunohistochemistry and/or real-time quantitative polymerase chain reaction. Results In vitro, E. granulosus PSC could be killed by Vepm at a concentration of 0.5 μg/ml or higher within 8 days. Under these conditions, the ultrastructure of PSC was damaged, and this damage was accompanied by obvious calcium loss and downregulation of CaMKII mRNA expression. In vivo, the weight and the calcium content of E. multilocularis metacestodes from mice were reduced after treatment with 40 mg/kg Vepm, and an elevation of the calcium content in the sera and livers of infected mice was observed. In addition, downregulation of CaM and CaMKII protein and mRNA expression in the livers of mice infected with E. multilocularis metacestodes was found after treatment with Vepm. Conclusions Vepm exerted a parasiticidal effect against Echinococcus both in vitro and in vivo through downregulating the expression of Ca2+/CaM-CaMKII, which was over-activated by parasitic infection. The results suggest that Ca2+/CaM-CaMKII may be a novel drug target, and that Vepm is a potential anti-echinococcal drug for the future control of echinococcosis.

Ca2+-independent contraction of longitudinal ileal smooth muscle is potentiated by a zipper-interacting protein kinase pseudosubstrate peptide

2009 ◽  
Vol 297 (2) ◽  
pp. G361-G370 ◽  
Author(s):  
Eikichi Ihara ◽  
Lori Moffat ◽  
Meredith A. Borman ◽  
Jennifer E. Amon ◽  
Michael P. Walsh ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Protein Kinase ◽  
Conformational Changes ◽  
Kinase Inhibitor ◽  
Smooth Muscles ◽  
Dominant Negative ◽  
Myosin Phosphatase ◽  
Interacting Protein ◽  
Zipper Interacting Protein Kinase

As a regulator of smooth muscle contraction, zipper-interacting protein kinase (ZIPK) can directly phosphorylate the myosin regulatory light chains (LC20) and produce contractile force. Synthetic peptides (SM-1 and AV25) derived from the autoinhibitory region of smooth muscle myosin light chain kinase can inhibit ZIPK activity in vitro. Paradoxically, treatment of Triton-skinned ileal smooth muscle strips with AV25, but not SM-1, potentiated Ca2+-independent, microcystin- and ZIPK-induced contractions. The AV25-induced potentiation was limited to ileal and colonic smooth muscles and was not observed in rat caudal artery. Thus the potentiation of Ca2+-independent contractions by AV25 appeared to be mediated by a mechanism unique to intestinal smooth muscle. AV25 treatment elicited increased phosphorylation of LC20 (both Ser-19 and Thr-18) and myosin phosphatase-targeting subunit (MYPT1, inhibitory Thr-697 site), suggesting involvement of a Ca2+-independent LC20 kinase with coincident inhibition of myosin phosphatase. The phosphorylation of the inhibitor of myosin phosphatase, CPI-17, was not affected. The AV25-induced potentiation was abolished by pretreatment with staurosporine, a broad-specificity kinase inhibitor, but specific inhibitors of Rho-associated kinase, PKC, and MAPK pathways had no effect. When a dominant-negative ZIPK [kinase-dead ZIPK(1–320)-D161A] was added to skinned ileal smooth muscle, the potentiation of microcystin-induced contraction by AV25 was blocked. Furthermore, pretreatment of skinned ileal muscle with SM-1 abolished AV25-induced potentiation. We conclude, therefore, that, even though AV25 is an in vitro inhibitor of ZIPK, activation of the ZIPK pathway occurs following application of AV25 to permeabilized ileal smooth muscle. Finally, we propose a mechanism whereby conformational changes in the pseudosubstrate region of ZIPK permit augmentation of ZIPK activity toward LC20 and MYPT1 in situ. AV25 or molecules based on its structure could be used in therapeutic situations to induce contractility in diseases of the gastrointestinal tract associated with hypomotility.

scholarly journals c-Jun N-Terminal Kinase Activation of Activator Protein-1 Underlies Homologous Regulation of the Gonadotropin-Releasing Hormone Receptor Gene in αT3-1 Cells

Endocrinology ◽  
2003 ◽  
Vol 144 (3) ◽  
pp. 839-849 ◽  
Author(s):  
Buffy S. Ellsworth ◽  
Brett R. White ◽  
Ann T. Burns ◽  
Brian D. Cherrington ◽  
Annette M. Otis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Protein Kinase ◽  
Cell Model ◽  
Receptor Gene ◽  
Critical Role ◽  
Dominant Negative ◽  
Activator Protein 1 ◽  
Activator Protein

Reproductive function is dependent on the interaction between GnRH and its cognate receptor found on gonadotrope cells of the anterior pituitary gland. GnRH activation of the GnRH receptor (GnRHR) is a potent stimulus for increased expression of multiple genes including the gene encoding the GnRHR itself. Thus, homologous regulation of the GnRHR is an important mechanism underlying gonadotrope sensitivity to GnRH. Previously, we have found that GnRH induction of GnRHR gene expression in αT3-1 cells is partially mediated by protein kinase C activation of a canonical activator protein-1 (AP-1) element. In contrast, protein kinase A and a cAMP response element-like element have been implicated in mediating the GnRH response of the GnRHR gene using a heterologous cell model (GGH3). Herein we find that selective removal of the canonical AP-1 site leads to a loss of GnRH regulation of the GnRHR promoter in transgenic mice. Thus, an intact AP-1 element is necessary for GnRH responsiveness of the GnRHR gene both in vitro and in vivo. Based on in vitro analyses, GnRH appeared to enhance the interaction of JunD, FosB, and c-Fos at the GnRHR AP-1 element. Although enhanced binding of cFos reflected an increase in gene expression, GnRH appeared to regulate both FosB and JunD at a posttranslational level. Neither overexpression of a constitutively active Raf-kinase nor pharmacological blockade of GnRH-induced ERK activation eliminated the GnRH response of the GnRHR promoter. GnRH responsiveness was, however, lost in αT3-1 cells that stably express a dominant-negative c-Jun N-terminal kinase (JNK) kinase, suggesting a critical role for JNK in mediating GnRH regulation of the GnRHR gene. Consistent with this possibility, we find that the ability of forskolin and membrane-permeable forms of cAMP to inhibit the GnRH response of the GnRHR promoter is associated with a loss of both JNK activation and GnRH-mediated recruitment of the primary AP-1-binding components.

scholarly journals The Kinase Specificity of Protein Kinase Inhibitor Peptide

2021 ◽  
Vol 12 ◽  
Author(s):  
Yao Chen ◽  
Bernardo L. Sabatini
Keyword(s):  
Protein Kinase ◽  
Kinase Inhibitor ◽  
Protein Kinase Inhibitor ◽  
Temporal Specificity ◽  
Kinase C ◽  
Endogenous Protein ◽  
Inhibitor Peptide ◽  
Kinase Specificity ◽  
G Protein Coupled

G-protein-coupled-receptor (GPCR) signaling is exquisitely controlled to achieve spatial and temporal specificity. The endogenous protein kinase inhibitor peptide (PKI) confines the spatial and temporal spread of the activity of protein kinase A (PKA), which integrates inputs from three major types of GPCRs. Despite its wide usage as a pharmaceutical inhibitor of PKA, it was unclear whether PKI only inhibits PKA activity. Here, the effects of PKI on 55 mouse kinases were tested in in vitro assays. We found that in addition to inhibiting PKA activity, both PKI (6–22) amide and full-length PKIα facilitated the activation of multiple isoforms of protein kinase C (PKC), albeit at much higher concentrations than necessary to inhibit PKA. Thus, our results call for appropriate interpretation of experimental results using PKI as a pharmaceutical agent. Furthermore, our study lays the foundation to explore the potential functions of PKI in regulating PKC activity and in coordinating PKC and PKA activities.

scholarly journals Innate triggering and antiviral effector functions of activin A

2021 ◽  
Author(s):  
Kinda Al-Hourani ◽  
Narayan Ramamurthy ◽  
Emanuele Marchi ◽  
Ruth M Eichinger ◽  
Lian N Lee ◽  
...  
Keyword(s):  
Viral Infection ◽  
Influenza A ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Activin A ◽  
Type I ◽  
Type I Ifn ◽  
Effector Functions

First-line defence against viral infection is contingent upon rapid detection of conserved viral structural and genomic motifs by germline-encoded pattern recognition receptors, followed by activation of the type I IFN system and establishment of an intracellular antiviral state. Novel antiviral functions of bone morphogenetic protein and related activin cytokines, acting in conjunction with, and independently of, type I IFN, have recently been described. Activin A mediates multiple innate and adaptive immune functions, including antiviral effects. However, how such effects are mediated and how activin might be triggered by viral infection have not been defined. Here we addressed this in vivo and in vitro, in humans and mice. Transcriptomic analyses delineated strikingly congruent patterns of gene regulation in hepatocytes stimulated with recombinant activin A and IFNα in vitro. Activin A mRNA, encoded by INHBA, is induced upon activation of RIG-I, MDA5 and TLR7/8 viral nucleic acid sensors in vitro, across multiple cell lines and in human peripheral blood mononuclear cells. In vivo, infection of mice with influenza A also upregulated Inhba mRNA in the lung; this local upregulation of Inhba is retained in MAVS knockout mice, indicating a role for non-RIG-I-like receptors in its induction. Activin induction and signalling were also detectable in patients with chronic viral hepatitis. Together, these data suggest Activin A is triggered in parallel with type I IFN responses and can trigger related antiviral effector functions. This model has implications for the development of targeted antiviral therapies, in addition to revealing novel facets of activin biology.

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