Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During early development, progenitors of the heart valves and septa are formed by epithelial-mesenchymal transformation (EMT) of endothelial cells in the atrioventricular (AV) canal. Previously, we showed that pertussis toxin, a specific inhibitor of a subset of G proteins, inhibited EMT in chick AV canal cultures. This study examines in detail the effects of pertussis toxin on the process of EMT. One of the major mediators of EMT is Transforming Growth Factor beta 3 (TGFbeta3) which acts through the TGFbeta Type II receptor. To determine whether pertussis toxin affects EMT via the TGFbeta Type II receptor pathway, we compared AV cultures treated with pertussis toxin and TGFbeta Type II receptor blocking antibody. Pertussis toxin inhibited several elements of EMT. At all stages tested, pertussis toxin blocked endothelial cell-cell separation, cell hypertrophy, and the cellular polarization associated with endothelial activation. These activities were unaffected by TGFbeta Type II receptor antibodies. Pertussis toxin also reduced transformed mesenchymal cell migration by 61%. The expression patterns of several proteins (as markers of EMT) were analyzed in untreated, pertussis toxin-treated, and TGFbeta Type II receptor blocking antibody-treated cultures. These markers were alpha-smooth muscle actin, Mox-1, fibrillin 2, tenascin, cell surface beta 1,4 galactosyltransferase (GalTase), and integrin alpha6. Clear differences in marker expression were found between the two inhibitors. For example, in all cells, pertussis toxin inhibited expression of alpha-smooth muscle actin and GalTase while TGFbeta Type II receptor antibody treatment increased expression of these two proteins. These data suggest that G protein-mediated signaling is required for several elements of EMT. Furthermore, distinct G protein and TGFbeta signal transduction pathways mediate discrete components of EMT.
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PMID:Epithelial-mesenchymal transformation in the embryonic heart is mediated through distinct pertussis toxin-sensitive and TGFbeta signal transduction mechanisms. 991 78

To elucidate the factor(s) accelerating the autoimmune disease processes, we induced two types of experimental autoimmune encephalomyelitis (EAE), severe and very mild, in F344 rats by immunization with myelin basic protein (MBP) plus pertussis toxin (PT) (PT+) or with MBP alone (PT-) and compared the differences between the two. Immunohistochemical examinations showed that although the nature of inflammation was essentially the same between the two groups, the proportion of Vbeta8.2(+) T cells in the CNS lesion of PT (+) rats was larger than that of PT (-) rats. Cytokine analysis by competitive PCR revealed that IL-10 mRNA in the lymphoid organ was significantly suppressed in the PT(+) group, whereas levels of IFN-gamma,TNF-alpha and TGF-beta mRNA were insignificantly different after PT administration. In addition, T cells taken from PT (+) rats proliferated well in response to MBP, while those from PT (-) rats showed a marginal response to the same antigen. However, this finding does not indicate the switching of non-encephalitogenic to encephalitogenic T cells upon PT administration because PT (-) rats contained encephalitogenic T cells and/or their precursor cells as revealed by adoptive transfer experiments. Taken together, these findings suggest that suppression of IL-10 by PT administration is the major factor contributing to the exacerbation of EAE in PT(+) rats.
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PMID:Analysis of experimental autoimmune encephalomyelitis induced in F344 rats by pertussis toxin administration. 1068 10

The presence of endothelin-1 receptor proteins and the expression of their specific mRNAs were studied using 1st passage confluent monolayers of articular chondrocytes, isolated from 1-month and 18-month-old rats following 24-h incubation with several growth factors and cytokines. The ET-1- binding sites were predominantly of ETA subtype since BQ123, but not IRL1038 (ETB receptor subtype agonist), effectively blocked 125I-ET-1 binding. The 18-month-old rat cell monolayers bear approximately twice as many 125I-ET-1-binding sites as the 1-month-old rat cells. PDGF, EGF, and IGF-1 increased the number of binding sites in a concentration-dependent manner in both old and young rat cells with PDGF being the most active and EGF more active than IGF-1. IL-1beta, more potently than LPS, increased the number of binding sites in young rat cells only, whereas b-FGF, TGF-beta and GM-CSF had no effect or decreased slightly 125I-ET-1 binding in both types of cells. TNF-alpha strongly decreased the number of binding sites on both young and old rat cells, only. RT-PCR showed an increased expression of the specific ETA mRNA with the age of animals and in the presence of 50 ng/ml PDGF BB only. The incubation of the cells with ETs 1-3 for 10 min resulted in a 50% decrease of cellular cAMP but the blocking of the receptors with BQ123 prior to their exposure to ETs had no effect on cAMP production whereas IRL1038 counteracted this effect only marginally. This suggests a receptor-independent mechanism for ETs-induced inhibition of cAMP production. However, a 10-min co-incubation of cells with ET-1 and with one of the following agents: cholera toxin, pertussis toxin, indomethacin, L-NMA, U73122 and calphostin resulted in an almost complete (calphostin) or partial suppression of ET-1-induced inhibition of cAMP production. The significance of these findings is unclear but the increased density of ET-1 binding sites on old rat cells and its regulation by certain growth factors or cytokines suggest the involvement of ET-1 in aging and possibly in age-related diseases.
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PMID:Endothelin-1 receptors on cultured rat articular chondrocytes: regulation by age, growth factors, and cytokines, and effect on cAMP production. 1129 69

Transforming growth factor beta 1 (TGF-beta1) affects growth plate chondrocytes through Smad-mediated mechanisms and has been shown to increase protein kinase C (PKC). This study determined if PKC mediates the physiological response of rat costochondral growth zone (GC) chondrocytes to TGF-beta1; if the physiological response occurs via type II or type III TGF-beta receptors, and, if so, which receptor mediates the increase in PKC; and the signal transduction pathways involved. Treatment of confluent GC cells with TGF-beta1 stimulated [(3)H]thymidine and [(35)S]sulfate incorporation as well as alkaline phosphatase (ALPase) and PKC specific activities. Inhibition of PKC with chelerythrine, staurosporine, or H-7 caused a dose-dependent decrease in these parameters, indicating that PKC signaling was involved. TGF-beta1-dependent PKC and the physiological response of GC cells to TGF-beta1 was reversed by anti-type II TGF-beta receptor antibody and soluble type II TGF-beta receptor, showing that TGF-beta1 mediates these effects through the type II receptor. The increase in [3H]thymidine incorporation and ALPase specific activity were also regulated by protein kinase A (PKA) signaling, since the effects of TGF-beta1 were partially blocked by the PKA inhibitor H-8. The mechanism of TGF-beta1 activation of PKC is through phospholipase A(2) (PLA(2)) and not through phospholipase C (PLC). Arachidonic acid increased PKC in control cultures and was additive with TGF-beta1. Prostanoids are required, as indomethacin blocked the effect of TGF-beta1, and Cox-1, but not Cox-2, is involved. TGF-beta1 stimulates prostaglandin E(2) (PGE(2)) production and exogenous PGE(2) stimulates PKC, but not as much as TGF-beta1, suggesting that PGE(2) is not sufficient for all of the prostaglandin effect. In contrast, TGF-beta1 was not regulated by diacylglycerol; neither dioctanoylglycerol (DOG) nor inhibition of diacylglycerol kinase with R59022 had an effect. G-proteins mediate TGF-beta1 signaling at different levels in the cascade. TGF-beta1-dependent increases in PGE(2) levels and PKC were augmented by the G protein activator GTP gamma S, whereas inhibition of G-protein activity via GDP beta S, pertussis toxin, or cholera toxin blocked stimulation of PKC by TGF-beta1, indicating that both G(i) and G(s) are involved. Inhibition of PKA with H-8 partially blocked TGF-beta1-dependent PKC, suggesting that PKA inhibition on the physiological response was via PKA regulation of PKC signaling. This indicates that multiple interacting signaling pathways are involved: TGF-beta1 stimulates PLA(2) and prostaglandin release via the action of Cox-1 on arachidonic acid. PGE(2) activates the EP2 receptor, leading to G-protein-dependent activation of PKA. PKA signaling results in increased PKC activity and PKC signaling regulates proliferation, differentiation, and matrix synthesis.
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PMID:Transforming growth factor-beta1 regulation of growth zone chondrocytes is mediated by multiple interacting pathways. 1206 64

We show that the pertussis toxin B oligomer (PTX-B), and the PTX mutant PT9K/129G, which is safely administered in vivo, inhibit both transcription and secretion of TGF-beta elicited by HIV-1 Tat in NK cells. Tat-induced TGF-beta mRNA synthesis is also blocked by the ERK1 inhibitor PD98059, suggesting that ERK1 is needed for TGF-beta production. Moreover, Tat strongly activates the c-Jun component of the multimolecular complex AP-1, whereas TGF-beta triggers c-Fos and c-Jun. Of note, treatment of NK cells with PTX-B or PT9K/129G inhibits Tat- and TGF-beta-induced activation of AP-1. TGF-beta enhances starvation-induced NK cell apoptosis, significantly reduces transcription of the antiapoptotic protein Bcl-2, and inhibits Akt phosphorylation induced by oligomerization of the triggering NK cell receptor NKG2D. All these TGF-beta-mediated effects are prevented by PTX-B or PT9K/129G through a PI3K-dependent mechanism, as demonstrated by use of the specific PI3K inhibitor, LY294002. Finally, PTX-B and PT9K/129G up-regulate Bcl-x(L), the isoform of Bcl-x that protects cells from starvation-induced apoptosis. It is of note that in NK cells from patients with early HIV-1 infection, mRNA expression of Bcl-2 and Bcl-x(L) was consistently lower than that in healthy donors; interestingly, TGF-beta and Tat were detected in the sera of these patients. Together, these data suggest that Tat-induced TGF-beta production and the consequent NK cell failure, possibly occurring during early HIV-1 infection, may be regulated by PTX-B and PT9K/129G.
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PMID:Pertussis toxin (PTX) B subunit and the nontoxic PTX mutant PT9K/129G inhibit Tat-induced TGF-beta production by NK cells and TGF-beta-mediated NK cell apoptosis. 1587 99

Mesenchymal stem cells (MSCs) can differentiate into diverse cell types including adipogenic, osteogenic, chondrogenic and myogenic lineages. In the present study, we demonstrated for the first time that sphingosylphosphorylcholine (SPC) induces differentiation of human adipose-tissue-derived mesenchymal stem cells (hATSCs) to smooth-muscle-like cell types. SPC increased the expression levels of several smooth-muscle-specific genes, such as those for alpha-smooth-muscle actin (alpha-SMA), h1-calponin and SM22alpha, as effectively as transforming growth factor beta (TGF-beta1) and TGF-beta3. SPC elicited delayed phosphorylation of Smad2 after 24 hours exposure, in contrast to rapid phosphorylation of Smad2 induced by TGF-beta treatment for 10 minutes. Pretreatment of the cells with pertussis toxin or U0126, an MEK inhibitor, markedly attenuated the SPC-induced expression of beta-SMA and delayed phosphorylation of Smad2, suggesting that the Gi/o-ERK pathway is involved in the increased expression of alpha-SMA through induction of delayed Smad2 activation. In addition, SPC increased secretion of TGF-beta1 through an ERK-dependent pathway, and the SPC-induced expression of alpha-SMA and delayed phosphorylation of Smad2 were blocked by SB-431542, a TGF-beta type I receptor kinase inhibitor, or anti-TGF-beta1 neutralizing antibody. Silencing of Smad2 expression with small interfering RNA (siRNA) abrogated the SPC-induced expression of alpha-SMA. These results suggest that SPC-stimulated secretion of TGF-beta1 plays a crucial role in SPC-induced smooth muscle cell (SMC) differentiation through a Smad2-dependent pathway. Both SPC and TGF-beta increased the expression levels of serum-response factor (SRF) and myocardin, transcription factors involved in smooth muscle differentiation. siRNA-mediated depletion of SRF or myocardin abolished the alpha-SMA expression induced by SPC or TGF-beta. These results suggest that SPC induces differentiation of hATSCs to smooth-muscle-like cell types through G(i/o)-ERK-dependent autocrine secretion of TGF-beta, which activates a Smad2-SRF/myocardin-dependent pathway.
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PMID:Sphingosylphosphorylcholine induces differentiation of human mesenchymal stem cells into smooth-muscle-like cells through a TGF-beta-dependent mechanism. 1710 65

Mice deficient in the G-protein alpha subunit G(i)alpha(2) spontaneously develop colitis and colon cancer. IL-11 is a pleiotropic cytokine known to protect the intestinal epithelium from injury in animal models of colitis and is produced by subepithelial myofibroblasts in response to inflammatory mediators including TGF-beta, IL-1beta, and PGE(2). Arachidonic acid release and subsequent PGE(2) production is significantly decreased in the colonic mucosa of G(i)alpha(2)-/- mice, and we hypothesized that this would affect mucosal IL-11 production. Mucosal levels of IL-11 were found to be significantly decreased in G(i)alpha(2)-/- mice despite the presence of mild colitis. Primary cultures of G(i)alpha(2)-/- intestinal and colonic myofibroblasts (IMF and CMF, respectively) produced less basal and TGF-beta or IL-1beta-stimulated IL-11 mRNA and protein than wild-type cells. Inhibitors of ERK or p38 MAPK activation dose dependently inhibited IMF and CMF IL-11 production in response to TGF-beta stimulation, whereas 16,16 dimethyl-PGE(2) and prostanoid receptor subtype-selective agonists induced IL-11 production. Treatment of animals with the EP4-specific agonist ONO-AE1-329 resulted in enhanced mucosal levels of IL-11, and increased IL-11 production by ex vivo cultured CMF. Modulation of cAMP levels produced diverging results, with enhancement of TGF-beta-induced IL-11 release in IMF pretreated with 8-Br-cAMP and inhibition in cells treated either with pertussis toxin or the PKA inhibitor H-89. These data suggest a physiological role for prostaglandins, MAPK signaling, and cAMP signaling for the production of myofibroblast-derived IL-11 in the mouse intestinal mucosa.
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PMID:Decreased MAPK- and PGE2-dependent IL-11 production in Gialpha2-/- colonic myofibroblasts. 1733 78

Studies concerned evaluation of differences between parameters of cell-mediated immunity in mice, induced with whole-cell and acellular pertussis vaccines with subsequent challenge with B. pertussis strains harbouring different ptxS1/prn allele genes. In the study, concentrations of IFN-gamma/Il-2 and 1l-4/Il-5 in supernatants of cultured mice splenocytes have been determined to evaluate differences in Th1 or Th2 lymphocytes subpopulation response. Simultaneously, studies of intracellular expression of genes encoding of Il-2, Il-12, IFN-gamma and Il-4, Il-5, Il-10, Il-13 in mice splenocytes, and genes encoding factors involved in inflammatory process in the lung tissue (GM-CSF, TNF-alpha, Il-1beta, Il-6 i TGF-beta) have been performed on RNA level. The obtained results, confirmed high polarization of immunological response toward Th1 in mice immunized with DTP vaccine with whole-cell pertussis component, and toward Th2 in mice immunized with acellular pertussis vaccine. Inflammatory process in the lung tissue was more pronounced in animals immunized with whole-cell pertussis vaccine. There were no quantitative differences of analysed factors involved in the immune response among mice challenged B. pertussis strains containing different ptxS1/prn composition.
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PMID:[Analysis of chosen parameters of immuno response in mice immunized with whole-cell or acellular pertussis vaccines and challenged with B. pertussis strains harbouring different ptxS1/prn allele genes combinations]. 1792 11

Experimental autoimmune encephalomyelitis (EAE) is a primary animal model of multiple sclerosis (MS). MS predominantly presents with evidence of lesions in the subcortical periventricular white matter regions of the brain. Research into the pathogenesis of the demyelinating lesions in the brain has been hampered by the fact that conventional models of EAE present with progressive ascending paralysis which recapitulates mainly the spinal cord lesions of multiple sclerosis. There is little evidence of brain involvement. Systemic administration of pertussis toxin (PTx) has been shown to induce the proinflammatory cascade of TGF-beta, IL-6, and Th17 in the central nervous system, which recently has been identified as essential in the development of EAE. To determine whether intracerebroventricular (icv) administration of PTx would result in subcortical periventricular demyelinating lesions in the brain, we examined the effect in a MOG induced EAE model. We found that icv PTx induced subcortical periventricular brain lesions that resemble the pathologic demyelinating lesions of MS. Moreover, icv PTx induced Th17 infiltration and increased expression of cytokines IL-6 and TGF-beta. We thus generated a highly reproducible model with remarkable histological similarities to the predominant demyelinating brain lesions seen in MS.
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PMID:A new EAE model of brain demyelination induced by intracerebroventricular pertussis toxin. 1833 8

Activin A is a dimeric protein, member of the transforming growth factor (TGF)-beta family that plays a crucial role in wound repair and in fetal tolerance. Emerging evidence also proposes activin A as a key mediator in inflammation. This study reports that activin A induces the directional migration of immature myeloid dendritic cells (iDCs) through the activation of ALK4 and ActRIIA receptor chains. Conversely, activin A was not active on plasmacytoid dendritic cells (DCs) or mature myeloid DCs. iDC migration to activin A was phosphatidylinositol 3-kinase gamma-dependent, Bordetella pertussis toxin- and cycloheximide-sensitive, and was inhibited by M3, a viral-encoded chemokine-binding protein. In a real-time video microscopy-based migration assay, activin A induced polarization of iDCs, but not migration. These characteristics clearly differentiated the chemotactic activities of activin A from TGF-beta and classic chemokines. By the use of combined pharmacologic and low-density microarray analysis, it was possible to define that activin-A-induced migration depends on the selective and polarized release of 2 chemokines, namely CXC chemokine ligands 12 and 14. This study extends the proinflammatory role of activin A to DC recruitment and provides a cautionary message about the reliability of the in vitro chemotaxis assays in discriminating direct versus indirect chemotactic agonists.
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PMID:Activin A induces dendritic cell migration through the polarized release of CXC chemokine ligands 12 and 14. 1933 94


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