Adenosine pretreatment attenuates angiotensin II-mediated p38 MAPK activation in a protein kinase A dependent manner

Abstract Background: Adenosine is known as a protective and anti-inflammatory nucleoside. Angiotensin II is the main hormone of the renin-angiotensin system. It is associated with endothelial permeability, recruitment, and activation of the immune cells through induction of inflammatory mediators. Matrix metalloproteinase-9 (MMP-9) plays an important role in inflammatory processes mediated by macrophages. Objectives: Investigate whether adenosine pretreatment modulates angiotensin II-induced MMP-9 expression and activation of signaling molecules. Methods: Human monocytic U-937 cells were treated with either adenosine or angiotensin II alone or angiotensin II following a pretreatment with adenosine. Supernatants were analyzed for MMP-9 activity by zymography method. MMP-9 gene expression was analyzed using real-time PCR. Activation of inflammatory mediators IκB-α, NF-κB, JNK, p38 MAPK, and STAT3 were analyzed by a multi-target ELISA kit. Association of Protein kinase A (PKA) in adenosine effects was studied by pre-incubation with H89, a selective PKA inhibitor. Results: Treatment of the cells with angiotensin II significantly increased MMP-9 production (p <0.05). Adenosine pretreatment did not attenuate this angiotensin II effect. Angiotensin II treatment induced NF-κB, JNK and p38 activation. Pretreatment with adenosine prior to angiotensin II stimulation showed a 40% inhibitory effect on p38 induction (p <0.05). This effect was reversed by PKA inhibition. Conclusion: The present data confirmed that monocytic MMP-9 was a target gene for angiotensin II. Adenosine pretreatment did not inhibit MMP-9 increase in response to angiotensin II. However, it showed a potential inhibitory effect on angiotensin II inflammatory signaling.

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Protein kinase A activity modulates natriuretic peptide-dependent cGMP accumulation in renal cells

AJP Cell Physiology ◽

10.1152/ajpcell.1997.272.1.c82 ◽

1997 ◽

Vol 272 (1) ◽

pp. C82-C89 ◽

Cited By ~ 11

Author(s):

S. Ledoux ◽

J. C. Dussaule ◽

C. Chatziantoniou ◽

N. Ardaillou ◽

S. Vandermeersch ◽

...

Keyword(s):

Protein Kinase ◽

Protein Kinase A ◽

Cholera Toxin ◽

Natriuretic Peptide ◽

Cell Types ◽

Inhibitory Effect ◽

Nitric Oxide Donor ◽

Dependent Manner ◽

Cgmp Production ◽

Kinase A

The purpose of this work was to examine whether the level of cAMP accumulation and protein kinase A (PKA) activity influence atrial natriuretic factor (ANF)-dependent guanosine 3',5'-cyclic monophosphate (cGMP) production in two renal cell types: rabbit cortical vascular smooth muscle cells (RCSMC) and SV-40-transformed human glomerular visceral epithelial cells (HGVEC-SV1). N-[2-(p-bromocinnamylamino)ethyl]- 5-isoquinolinesulfonamide (H-89), a PKA inhibitor, decreased ANF-stimulated cGMP production in RCSMC in a time- and concentration-dependent manner. ANF-stimulated cGMP production was markedly inhibited after prolonged 9- and 18-h incubations with 25 microM H-89 (52 and 65%, respectively) but was not altered after exposure of cells to this agent for 1 h. 1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine and N-(2-[methylamino]ethyl)-5-isoquinolinesulfonamide, protein kinase inhibitors not selective for PKA, did not reproduce the effect of H-89, even at higher concentrations (50 and 100 microM). Cycloheximide (10 microM), a protein synthesis inhibitor, limited the inhibitory effect of H-89, although alone it did not modify the ANF-stimulated cGMP production. H-89 did not affect cGMP production when it was stimulated by SIN-1, a nitric oxide donor. Prolonged incubation (18 h) with 8-bromo cAMP or cholera toxin, an activator of Gs protein resulting in adenylate cyclase stimulation, enhanced ANF-dependent cGMP production by 225 and 176%, respectively. This stimulatory effect was blocked by 25 microM H-89. 125I-ANF binding to RCSMC at 4 degrees C was not affected by preincubation of the cells with H-89. There was a 44% decrease in the expression of ANF C receptors measured as the ANF-(4-23)-displaceable 125I-ANF binding at 37 degrees C, which could not, however, explain the inhibitory effect of H-89 on cGMP production. Modulation of ANF- and C-type natriuretic peptide-dependent cGMP production by H-89 and cholera toxin was also found in HGVEC-SV1 with the same characteristics as in RCSMC. Taken together, these results suggest that PKA activity controls the function of natriuretic peptide guanylate cyclase-coupled receptors in the two cell types studied. PKA-dependent inhibition of a negatively regulatory protein distinct from the receptor itself seems necessary for a full cGMP response.

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High glucose-associated osmolality promotes adipocytogenic differentiation of primary rat osteoblasts in a protein kinase A and phosphatidylinositol 3-kinase/Akt-dependent manner

Biologia ◽

10.1515/biolog-2015-0156 ◽

2015 ◽

Vol 70 (10) ◽

Author(s):

Yu Zhang ◽

Pu Feng ◽

Jianhong Yang

Keyword(s):

Gene Expression ◽

Protein Kinase ◽

Protein Kinase A ◽

Real Time ◽

High Glucose ◽

Marker Gene ◽

Dependent Manner ◽

Phosphatidylinositol 3 Kinase ◽

Marker Gene Expression ◽

Kinase A

AbstractIncreased risk of osteoporosis in patients with diabetes mellitus may be related to hyperglycemia. However, the potential mechanisms accounting for diabetic bone disorder remain unresolved. The present study investigated the effects of high glucose-associated osmolality on differentiation of primary rat calvarial osteoblasts. Osteoblastogenic differentiation was determined by bone nodule staining for mineralization assay, enzyme-linked immunosorbent assay for type I collagen production and real-time polymerase chain reaction (PCR) for osteoblastogenic marker gene expression. Adipocytogenic differentiation was assessed by oil red O staining for lipid accumulation and real-time PCR for adipocytogenic marker gene expression. The phosphorylations of protein kinase A (PKA) and Akt were measured with or without specific inhibitors to confirm osmolality involved signalling pathways. The results showed that high glucose-associated osmolality significantly promoted adipocytogenic differentiation, manifested by increased lipid droplet formation and gene expression of adipocytogenic markers including adipocyte fatty acid binding protein (aP2), adipsin and peroxisome proliferator-activated receptor gamma (PPARγ). Meanwhile, high glucose-associated osmolality inhibited osteoblastogenic differentiation, characterized by decreased collagen I protein production and cell mineralization, as well as gene expression of osteoblastogenic markers including collagen I, osteocalcin and runt-related transcription factor 2 (Runx2). More importantly, we demonstrated for the first time that high glucose-associated osmolality induced adipocytogenic differentiation and suppressed osteoblastogenic differentiation in a PKA and phosphatidylinositol 3-kinase (PI3K)/Akt-dependent manner. These results indicated that osmolality was involved in high glucose-induced osteoblast trans-differentiation into adipocyte-like cell and suppression of cellular osmolality could provide novel therapeutic approach for diabetic osteopenia.

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Complex effects of kinase localization revealed by compartment-specific regulation of protein kinase A activity

10.1101/2021.04.08.439038 ◽

2021 ◽

Author(s):

Rebecca LaCroix ◽

Benjamin Lin ◽

Andre Levchenko

Keyword(s):

Cell Migration ◽

Protein Kinase ◽

Protein Kinase A ◽

Kinase Activity ◽

Single Cells ◽

Regulatory Subunit ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Specific Regulation ◽

Kinase A

SummaryKinase activity in signaling networks frequently depends on regulatory subunits that can both inhibit activity by interacting with the catalytic subunits and target the kinase to distinct molecular partners and subcellular compartments. Here, using a new synthetic molecular interaction system, we show that translocation of a regulatory subunit of the protein kinase A (PKA-R) to the plasma membrane has a paradoxical effect on the membrane kinase activity. It can both enhance it at lower translocation levels, even in the absence of signaling inputs, and inhibit it at higher translocation levels, suggesting its role as a linker that can both couple and decouple signaling processes in a concentration-dependent manner. We further demonstrate that superposition of gradients of PKA-R abundance across single cells can control the directionality of cell migration, reversing it at high enough input levels. Thus complex in vivo patterns of PKA-R localization can drive complex phenotypes, including cell migration.

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Terbutaline, forskolin and cAMP reduce secretion of aqueous humour in the isolated bovine eye

PLoS ONE ◽

10.1371/journal.pone.0244253 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0244253

Author(s):

Mohammad Shahidullah ◽

William Stuart Wilson ◽

Kazi Rafiq ◽

Mahmudul Hasan Sikder ◽

Jannatul Ferdous ◽

...

Keyword(s):

Protein Kinase ◽

Cyclic Amp ◽

Protein Kinase A ◽

Aqueous Humour ◽

Calcium Release ◽

Drug Effects ◽

Inhibitory Effect ◽

Plateau Phase ◽

Intracellular Ca ◽

Kinase A

In order to elucidate involvement of cyclic AMP and intracellular Ca2+,[Ca2+]i, in the modulation of aqueous humour formation (AHF), we studied the effects of terbutaline, forskolin and 8-Br-cAMP in the isolated bovine eye. We also studied the interaction of cAMP on calcium signaling in cultured ciliary epithelial (CE) cells. Drug effects on AHF were measured by fluorescein dilution. Drug effects on [Ca2+]i were studied by the fura-2 fluorescence ratio technique. Terbutaline (100 nmol-100 M), forskolin (30 nM-100 M) or 8-Br-cAMP (100 nM– 10 μM), administered in the arterial perfusate produced significant reductions in AHF. The AH reducing effect of terbutaline was blocked by a selective inhibitor of protein kinase A (KT-5720). ATP (100 M) caused a rapid, transient (peak) increase in [Ca2+]i followed by a sustained plateau phase lasting more than 5 minutes. Preincubation of the cells (6 min) with terbutaline, forskolin or 8-Br-cAMP significantly reduced the peak calcium response to ATP. The sustained plateau phase of the response, on the other hand, was augmented by each of the agents. KT-5720 partially reversed the inhibitory effect of terbutaline on the peak and totally inhibited its effect on the plateau phase. These data indicate: (a) that AHF in the bovine eye can be manipulated through cyclic AMP, operating via protein kinase A, (b) that protein kinase A can affect [Ca2+]i homeostasis, (c) that calcium release from the intracellular store, not the entry, affects AHF, and (d) that interaction of [Ca2+]i with cAMP plays a role in modulating AH secretion.

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Adrenomedullin Increases AP-1 Expression in Rat Mesangial Cells via Activation of Protein Kinase-A and p38 MAPK

Cellular Physiology and Biochemistry ◽

10.1159/000075124 ◽

2003 ◽

Vol 13 (6) ◽

pp. 367-374 ◽

Cited By ~ 6

Author(s):

Narayanan Parameswaran ◽

Carolyn Hall ◽

Laura McCabe ◽

William Spielman

Keyword(s):

Protein Kinase ◽

Protein Kinase A ◽

P38 Mapk ◽

Mesangial Cells ◽

Kinase A

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Inhibition of PAH transport by parathyroid hormone in OK cells: involvement of protein kinase C pathway

AJP Renal Physiology ◽

10.1152/ajprenal.1997.273.5.f674 ◽

1997 ◽

Vol 273 (5) ◽

pp. F674-F679 ◽

Cited By ~ 7

Author(s):

Junya Nagai ◽

Ikuko Yano ◽

Yukiya Hashimoto ◽

Mikihisa Takano ◽

Ken-Ichi Inui

Keyword(s):

Protein Kinase C ◽

Parathyroid Hormone ◽

Protein Kinase ◽

Protein Kinase A ◽

Regulatory Control ◽

Dependent Manner ◽

Transcellular Transport ◽

Ok Cells ◽

Kinase C ◽

Kinase A

We have previously shown that the p-aminohippurate (PAH) transport system in OK kidney epithelial cell line is under the regulatory control of protein kinase C. Parathyroid hormone (PTH) could activate protein kinase C, as well as protein kinase A, in OK cells. In the present study, the effect of PTH on PAH transport was studied in OK cells. PTH inhibited the transcellular transport of PAH from the basal to the apical side, as well as the accumulation of PAH in OK cells. Basolateral PAH uptake was inhibited by PTH in a dose- and time-dependent manner. Protein kinase A activators did not affect the transcellular transport or the accumulation of PAH. The PTH-induced inhibition of the accumulation of PAH was blocked by a protein kinase C inhibitor staurosporine. These results suggest that PTH inhibits the PAH transport in OK cells and that the messenger system mediated by protein kinase C, not protein kinase A, plays an important role in the regulation of PAH transport by PTH.

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Ca2+-, phorbol ester-, and cAMP-stimulated enzyme secretion from permeabilized rat pancreatic acini

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1986.250.5.g698 ◽

1986 ◽

Vol 250 (5) ◽

pp. G698-G708 ◽

Cited By ~ 4

Author(s):

T. Kimura ◽

K. Imamura ◽

L. Eckhardt ◽

I. Schulz

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Protein Kinase A ◽

Protein Release ◽

Enzyme Secretion ◽

Dependent Manner ◽

Intact Cells ◽

Pancreatic Acini ◽

Kinase C ◽

Kinase A

Enzyme secretion from the exocrine pancreas is stimulated by receptor-activated breakdown of phosphatidylinositol 4,5-bisphosphate and consequent rise of both inositol 1,4,5-trisphosphate (IP3) and diacylglycerol, which leads to Ca2+ release and to activation of protein kinase C, respectively. Another way involves receptor-mediated stimulation of adenylate cyclase and consequent rise of cAMP and activation of protein kinase A. In the present work we have studied direct stimulation, inhibition, and mutual interaction of these pathways on enzyme secretion from isolated rat pancreatic acini that had been permeabilized by treatment with saponin or digitonin. The data were compared with those obtained in isolated intact acini. The data show that with increasing free Ca2+ concentrations greater than 10(-6) M protein release increases in "leaky" but not in "intact" cells and is maximal at approximately 10(-3) M, increasing about twofold compared with that in the absence of Ca2+. In the presence of the acetylcholine analogue carbachol, this effect of Ca2+ is enhanced by about threefold in leaky cells and is also present in intact cells to a similar extent. cAMP and its analogues, dibutyryl cAMP (dbcAMP) and 8-bromo-cAMP stimulate protein release by about twofold in the presence of Ca2+ in leaky cells. In intact acini cAMP has no effect, and cAMP analogues stimulate enzyme secretion by about twofold in some but not all experiments. Similarly, forskolin, an activator of adenylate cyclases and inhibitors of cyclic nucleotide-dependent phosphodiesterases, such as 3-isobutyl-1-methylxanthine (IBMX) and R0 201724, stimulate protein release in permeabilized acini. The Ca2+-binding protein calmodulin has no effect on enzyme secretion, whereas the calmodulin antagonist trifluoperazine dihydrochloride stimulates protein release in leaky but not in intact acini. The activator of protein kinase C, 12-O-tetradecanoylphorbol 13-acetate (TPA) stimulates protein release in a Ca2+-dependent manner and enhances cAMP-induced secretion. The effects of carbachol, TPA, cAMP, and a combination of both TPA and cAMP are inhibited by the polyamine spermine in permeabilized cells. Spermine has no effect on carbachol-induced enzyme secretion in intact cells. The data suggest that enzyme secretion from pancreatic acinar cells is mediated by cAMP protein kinase A and by Ca2+ phospholipid protein kinase C in a Ca2+-dependent way and that interaction occurs between both pathways.

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The cross-regulation of Gi-protein by cholera toxin involves a phosphorylation by protein kinase A

Biochemical Journal ◽

10.1042/bj3060765 ◽

1995 ◽

Vol 306 (3) ◽

pp. 765-769 ◽

Cited By ~ 6

Author(s):

R Levistre ◽

M Berguerand ◽

G Bereziat ◽

J Masliah

Keyword(s):

Arachidonic Acid ◽

Protein Kinase ◽

Protein Kinase A ◽

Cholera Toxin ◽

Inhibitory Effect ◽

Negative Control ◽

Adp Ribosylation ◽

Gi Proteins ◽

Kinase A

Pretreatment of alveolar macrophages with cholera toxin inhibits the release of arachidonic acid induced by the chemotactic peptide N-formylmethionyl-leucyl-phenylalanine. The results presented here show that cholera toxin might exert its inhibitory effect through the phosphorylation of Gi alpha by protein kinase A (PKA). (1) Gi-proteins from cells pretreated with cholera toxin showed parallel increases in their sensitivity to ADP-ribosylation by toxins in vitro and in Gi alpha phosphorylation. By contrast, the Gi alpha concentration was unchanged. (2) Cholera toxin pretreatment also decreased the functional activity of Gi, as assessed by the inhibition (80%) of agonist-induced binding of guanosine-5′-[gamma-thio]triphosphate (GTP[gamma S]). (3) These effects of cholera toxin were blocked by a specific PKA inhibitor, N-(2-[methyl-amino]ethyl)-3-isoquinolinesulphonamide dihydrochloride (H8) and mimicked by a cyclic AMP (cAMP) analogue and a phosphatase inhibitor. (4) Gi alpha was also phosphorylated in vitro by the catalytic subunit of PKA. In contrast with other cell systems, the stimulation of protein kinase C seems to have no effect on the sensitivity of Gi to ADP-ribosylation or on its phosphorylation. Therefore, the phosphorylation of Gi-proteins by PKA seems to be the actual target of the negative control of arachidonic acid release via the cAMP-mediated pathway.

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Role of vaspin in porcine ovary: effect on signaling pathways and steroid synthesis via GRP78 receptor and protein kinase A†

Biology of Reproduction ◽

10.1093/biolre/ioaa027 ◽

2020 ◽

Vol 102 (6) ◽

pp. 1290-1305 ◽

Cited By ~ 2

Author(s):

Patrycja Kurowska ◽

Ewa Mlyczyńska ◽

Monika Dawid ◽

Joelle Dupont ◽

Agnieszka Rak

Keyword(s):

Protein Kinase ◽

Western Blot ◽

Protein Kinase A ◽

Signaling Pathways ◽

Dependent Manner ◽

Steroid Synthesis ◽

Ovarian Cells ◽

Vitro Effect ◽

Kinase A

Abstract Vaspin, visceral-adipose-tissue-derived serine protease inhibitor, is involved in the development of obesity, insulin resistance, inflammation, and energy metabolism. Our previous study showed vaspin expression and its regulation in the ovary; however, the role of this adipokine in ovarian cells has never been studied. Here, we studied the in vitro effect of vaspin on various kinase-signaling pathways: mitogen-activated kinase (MAP3/1), serine/threonine kinase (AKT), signal transducer and activator of transcription 3 (STAT3) protein kinase AMP (PRKAA1), protein kinase A (PKA), and on expression of nuclear factor kappa B (NFKB2) as well as on steroid synthesis by porcine ovarian cells. By using western blot, we found that vaspin (1 ng/ml), in a time-dependent manner, increased phosphorylation of MAP3/1, AKT, STAT3, PRKAA1, and PKA, while it decreased the expression of NFKB2. We observed that vaspin, in a dose-dependent manner, increased the basal steroid hormone secretion (progesterone and estradiol), mRNA and protein expression of steroid enzymes using real-time PCR and western blot, respectively, and the mRNA of gonadotropins (FSHR, LHCGR) and steroids (PGR, ESR2) receptors. The stimulatory effect of vaspin on basal steroidogenesis was reversed when ovarian cells were cultured in the presence of a PKA pharmacological inhibitor (KT5720) and when GRP78 receptor was knocked down (siRNA). However, in the presence of insulin-like growth factor type 1 and gonadotropins, vaspin reduced steroidogenesis. Thus, vaspin, by activation of various signaling pathways and stimulation of basal steroid production via GRP78 receptor and PKA, could be a new regulator of porcine ovarian function.

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Tauroursodeoxycholate Protects Rat Hepatocytes from Bile Acid-Induced Apoptosis via β1-Integrin- and Protein Kinase A-Dependent Mechanisms

Cellular Physiology and Biochemistry ◽

10.1159/000430262 ◽

2015 ◽

Vol 36 (3) ◽

pp. 866-883 ◽

Cited By ~ 10

Author(s):

Annika Sommerfeld ◽

Roland Reinehr ◽

Dieter Häussinger

Keyword(s):

Bile Acid ◽

Protein Kinase ◽

Protein Kinase A ◽

Rat Hepatocytes ◽

Β1 Integrin ◽

Dependent Manner ◽

Mitogen Activated Protein ◽

Induced Apoptosis ◽

Jnk Activation ◽

Kinase A

Background/Aims: Ursodeoxycholic acid, which in vivo is rapidly converted into its taurine conjugate, is frequently used for the treatment of cholestatic liver disease. Apart from its choleretic effects, tauroursodeoxycholate (TUDC) can protect hepatocytes from bile acid-induced apoptosis, but the mechanisms underlying its anti-apoptotic effects are poorly understood. Methods: These mechanisms were investigated in perfused rat liver and isolated rat hepatocytes. Results: It was found that TUDC inhibited the glycochenodeoxycholate (GCDC)-induced activation of the CD95 death receptor at the level of association between CD95 and the epidermal growth factor receptor. This was due to a rapid TUDC-induced β1-integrin-dependent cyclic AMP (cAMP) signal with induction of the dual specificity mitogen-activated protein (MAP) kinase phosphatase 1 (MKP-1), which prevented GCDC-induced phosphorylation of mitogen-activated protein kinase kinase 4 (MKK4) and c-jun-NH2-terminal kinase (JNK) activation. Furthermore, TUDC induced a protein kinase A (PKA)-mediated serine/threonine phosphorylation of the CD95, which was recently identified as an internalization signal for CD95. Furthermore, TUDC inhibited GCDC-induced CD95 targeting to the plasma membrane in a β1-integrin-and PKA-dependent manner. In line with this, the β1-integrin siRNA knockdown in sodium taurocholate cotransporting polypeptide (Ntcp)-transfected HepG2 cells abolished the protective effect of TUDC against GCDC-induced apoptosis. Conclusion: TUDC exerts its anti-apoptotic effect via a β1-integrin-mediated formation of cAMP, which prevents CD95 activation by hydrophobic bile acids at the levels of JNK activation and CD95 serine/threonine phosphorylation.

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