High CXCL6 drives matrix expression and correlate with markers of poor outcome in IPF

Signaling via G protein-coupled receptors (GPCRs) can modulate levels of cyclic adenosine monophosphate (cAMP) and shape the functions of fibroblasts in idiopathic pulmonary fibrosis (IPF). We have identified Chemokine (C-X-C) Motif Ligand 6 (CXCL6) as a potential pro-fibrotic GPCR ligand. We tested the function of CXCL6 in ex vivo human donor and fibrotic lung fibroblasts and in an animal model of pulmonary fibrosis. We also measured levels of CXCL6 in the blood and bronchoalveolar lavage (BAL) of patients with IPF. CXCL6 decreased cAMP levels in a dose-dependent manner in Donor and IPF Fibroblasts. CXCL6 mRNA and protein were localized to epithelial cells. Administration of mCXCL5 (LIX, murine CXCL6 homologue) to mice increased collagen synthesis with and without bleomycin. CXCL6 increased Collagen I and α-SMA levels in Donor and IPF Fibroblasts. Silencing of CXCR1/2 as well as Reparixin, a CXCR1/2 inhibitor, blocked effects of CXCL6. Treprostinil blocked effects of CXCL6 only on levels of α-SMA but not on Collagen I. CXCL6 levels in the BAL of two separate cohorts of patients with IPF was associated with poor survival. We conclude that high CXCL6 drives fibroblast function and correlates with poor outcomes in IPF.

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Identification of Paired-related Homeobox Protein 1 as a key mesenchymal transcription factor in Idiopathic Pulmonary Fibrosis

10.1101/2021.01.15.425870 ◽

2021 ◽

Author(s):

E. Marchal-Duval ◽

M. Homps-Legrand ◽

A. Froidure ◽

M. Jaillet ◽

M. Ghanem ◽

...

Keyword(s):

Transcription Factor ◽

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Ex Vivo ◽

Lung Fibroblasts ◽

Matrix Remodeling ◽

Dependent Manner ◽

Homeobox Protein

ABSTRACTMatrix remodeling is a salient feature of idiopathic pulmonary fibrosis (IPF). Targeting cells driving matrix remodeling could be a promising avenue for IPF treatment. Analysis of transcriptomic database identified the mesenchymal transcription factor PRRX1 as upregulated in IPF.PRRX1, strongly expressed by lung fibroblasts, was regulated by a TGF-β/PGE2 balance in vitro in control and IPF fibroblasts, while IPF fibroblast-derived matrix increased PRRX1 expression in a PDGFR dependent manner in control ones.PRRX1 inhibition decreased fibroblast proliferation by downregulating the expression of S phase cyclins. PRRX1 inhibition also impacted TGF-β driven myofibroblastic differentiation by inhibiting SMAD2/3 phosphorylation through phosphatase PPM1A upregulation and TGFBR2 downregulation, leading to TGF-β response global decrease.Finally, targeted inhibition of Prrx1 attenuated fibrotic remodeling in vivo with intra-tracheal antisense oligonucleotides in bleomycin mouse model of lung fibrosis and ex vivo using precision-cut lung slices.Our results identified PRRX1 as a mesenchymal transcription factor driving lung fibrogenesis.Brief SummaryInhibition of a single fibroblast-associated transcription factor, namely paired-related homeobox protein 1, is sufficient to dampen lung fibrogenesis.

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Polydatin Attenuates Carbachol-induced Contraction of Guinea Pig Gallbladder

Current Topics in Nutraceutical Research ◽

10.37290/ctnr2641-452x.18:34-38 ◽

2019 ◽

Vol 18 (1) ◽

pp. 34-38

Author(s):

Chen Lei ◽

Pan Xiang ◽

Shen Yonggang ◽

Song Kai ◽

Zhong Xingguo ◽

...

Keyword(s):

Protein Kinase ◽

Guinea Pig ◽

Smooth Muscles ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Cyclic Guanosine Monophosphate ◽

Guanosine Monophosphate ◽

Dependent Manner ◽

Underlying Mechanisms ◽

Dose Dependent

The aim of this study was to determine whether polydatin, a glucoside of resveratrol isolated from the root of Polygonum cuspidatum, warranted development as a potential therapeutic for ameliorating the pain originating from gallbladder spasm disorders and the underlying mechanisms. Guinea pig gallbladder smooth muscles were treated with polydatin and specific inhibitors to explore the mechanisms underpinning polydatin-induced relaxation of carbachol-precontracted guinea pig gallbladder. Our results shown that polydatin relaxed carbachol-induced contraction in a dose-dependent manner through the nitric oxide/cyclic guanosine monophosphate/protein kinase G and the cyclic adenosine monophosphate/protein kinase A signaling pathways as well as the myosin light chain kinase and potassium channels. Our findings suggested that there was value in further exploring the potential therapeutic use of polydatin in gallbladder spasm disorders.

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A Redox-controlled Molecular Switch Revealed by the Crystal Structure of a Bacterial Heme PAS Sensor

Journal of Biological Chemistry ◽

10.1074/jbc.m314199200 ◽

2004 ◽

Vol 279 (19) ◽

pp. 20186-20193 ◽

Cited By ~ 105

Author(s):

Hirofumi Kurokawa ◽

Dong-Sun Lee ◽

Miki Watanabe ◽

Ikuko Sagami ◽

Bunzo Mikami ◽

...

Keyword(s):

Water Molecule ◽

Protein Interactions ◽

Iron Reduction ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Molecular Switch ◽

Heme Iron ◽

Side Chain ◽

Dependent Manner ◽

Pas Domain

PAS domains, which have been identified in over 1100 proteins from all three kingdoms of life, convert various input stimuli into signals that propagate to downstream components by modifying protein-protein interactions. One such protein is theEscherichia coliredox sensor,EcDOS, a phosphodiesterase that degrades cyclic adenosine monophosphate in a redox-dependent manner. Here we report the crystal structures of the heme PAS domain ofEcDOS in both inactive Fe3+and active Fe2+forms at 1.32 and 1.9 Å resolution, respectively. The protein folds into a characteristic PAS domain structure and forms a homodimer. In the Fe3+form, the heme iron is ligated to a His-77 side chain and a water molecule. Heme iron reduction is accompanied by heme-ligand switching from the water molecule to a side chain of Met-95 from the FG loop. Concomitantly, the flexible FG loop is significantly rigidified, along with a change in the hydrogen bonding pattern and rotation of subunits relative to each other. The present data led us to propose a novel redox-regulated molecular switch in which local heme-ligand switching may trigger a global “scissor-type” subunit movement that facilitates catalytic control.

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Involvement of Cyclic Adenosine Monophosphate in the Regulation of Pupal Color Adaptation of the Butterfly, Inachis io

Zeitschrift für Naturforschung C ◽

10.1515/znc-1997-3-418 ◽

1997 ◽

Vol 52 (3-4) ◽

pp. 255-258 ◽

Cited By ~ 1

Author(s):

Gerhard Starnecker

Keyword(s):

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Intracellular Camp ◽

Dependent Manner ◽

Color Adaptation ◽

Yellow Color ◽

Pde Inhibitors ◽

Inachis Io ◽

Yellow Coloration ◽

Entire Central Nervous System

AbstractIn the butterfly Inachis io, a pupal melanization reducing factor (PMRF) which is located throughout the entire central nervous system controls the intensity of pigmentation of pupal cuticle depending on the background color of the pupation site. PMRF does not only reduce melanization but, in addition, enhances lutein incorporation in a dose-dependent manner to form pupae with yellow color on bright backgrounds.The present paper reports on the effects on pupal pigmentation caused by cyclic nucleo tides and phosphodiesterase (PDE) inhibitors which prevent degradation of cyclic nucleo tides. The injection of cAMP did not alter pupal coloration whereas its membrane-permeable analog dibutyryl-cAMP mimicked dose-dependently PMRF activity. Thus, pupae of reduced melanization and, in addition, enhanced yellow coloration were formed. This indicates that an increased intracellular cAMP level is capable of mediating PMRF effect. Also, the injection of the PDE inhibitor isobutylmethylxanthine (IBMX) caused dose-dependently pupae of reduced melanization and enhanced lutein incorporation.Theophylline (another PDE inhibitor) was only slightly effective (23% inhibition of melanization) at the highest dose compared to IBMX. The injection of cGMP and its analog dibutyryl-cGMP exhibited no melanization reducing effect.Extracts of abdominal ganglia (AG) which contained PMRF activity caused significantly brighter pupae when injected in combination with IBMX. However, this stimulation by IBMX became no longer effective at higher AG doses. Therefore, the present results are suggestive of an involvement of cAMP as a second messenger in the action of PMRF on pupal color adaptation.

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Inhibitory action of somatostatin-14 on hormone-stimulated cyclic adenosine monophosphate induction in porcine granulosa and luteal cells

Journal of Endocrinology ◽

10.1677/joe.0.1340297 ◽

1992 ◽

Vol 134 (2) ◽

pp. 297-306 ◽

Cited By ~ 12

Author(s):

K. Rajkumar ◽

D. E. Kerr ◽

R. N. Kirkwood ◽

B. Laarveld

Keyword(s):

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Inhibitory Effect ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Luteal Cells ◽

Camp Generation ◽

Camp Induction ◽

Camp Levels ◽

Somatostatin 14

ABSTRACT Somatostatin-14 (SRIF-14) inhibited, in a concentration-dependent manner, LH- and forskolin-stimulated cyclic adenosine monophosphate (cAMP) induction in porcine granulosa and luteal cells. The inhibitory effect of SRIF-14 on hormone-induced cAMP generation was more potent in porcine ovarian cells than in the GH-3 pituitary cell line. The inhibitory effect of SRIF-14 was impeded by neutralizing its biological activity with specific antiserum. Preincubation of luteal and granulosa cells with phorbol 12-myristate 13-acetate (PMA) enhanced LH- and forskolin-stimulated cAMP levels. SRIF-14 failed to inhibit LH- or forskolin-stimulated cAMP levels in cells preincubated with PMA. It is concluded that SRIF-14 inhibits hormone-stimulated cAMP induction in the porcine ovary. LH-induced protein kinase C activation may be physiologically important to alleviate the inhibitory effects of SRIF-14. Journal of Endocrinology (1992) 134, 297–306

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Stereoselective Interaction of Ketamine with Recombinant [micro sign], [small kappa, Greek], and [small delta, Greek] Opioid Receptors Expressed in Chinese Hamster Ovary Cells

Anesthesiology ◽

10.1097/00000542-199901000-00023 ◽

1999 ◽

Vol 90 (1) ◽

pp. 174-182 ◽

Cited By ~ 70

Author(s):

Kazuyoshi Hirota ◽

Hirobumi Okawa ◽

Balraj L. Appadu ◽

David K. Grandy ◽

Lakshmi A. Devi ◽

...

Keyword(s):

Opioid Receptors ◽

Room Temperature ◽

Chinese Hamster Ovary Cells ◽

Chinese Hamster ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Dependent Manner ◽

Ovary Cells ◽

Racemic Ketamine ◽

Dose Dependent

Background The authors examined the interaction of ketamine with recombinant mu, kappa, and delta opioid receptors and recombinant orphan opioid receptors expressed in Chinese hamster ovary cells (CHO-mu, CHO-kappa, CHO-delta, and CHO(ORL1), respectively). Methods CHO-mu, CHO-kappa, and CHO-delta membranes were incubated with the opioid receptor radioligand [3H]diprenorphine at room temperature. Ketamine (racemic, R(-) and S(+)) was included at concentrations covering the clinical range. CHO(ORL1) membranes were incubated with [125I]Tyr(14)nociceptin and racemic ketamine at room temperature. The effects of racemic ketamine and selective opioid receptor agonists (mu: [D-Ala2, MePhe4, Gly(ol)5] enkephalin (DAMGO); kappa: spiradoline or delta: [D-pen2, D-pen5] enkephalin (DPDPE)) on forskolin-stimulated cyclic adenosine monophosphate formation also were examined. Data are mean +/- SEM. Results Racemic ketamine increased the radioligand equilibrium dissociation constant for [3H]diprenorphine from 85+/-5 to 273+/-11, 91+/-6 to 154+/-16, and 372+/-15 to 855+/-42 pM in CHO-mu, CHO-kappa, and CHO-delta, respectively. The concentration of radioligand bound at saturation was unaffected. In CHO-mu and CHO-kappa cells, racemic ketamine did not slow the rate of naloxone-induced [3H]diprenorphine dissociation. Ketamine and its isomers also displaced [3H]diprenorphine binding to mu, kappa, and delta receptors in a dose-dependent manner, with pKi values for racemic ketamine of 4.38+/-0.02, 4.55+/-0.04, and 3.57+/-0.02, respectively. S(+)-ketamine was two to three times more potent than R(-)-ketamine at mu and kappa receptors. Racemic ketamine displaced [125I]Tyr(14)nociceptin with an estimated affinity constant of 0.5 mM. Racemic ketamine inhibited the formation of cyclic adenosine monophosphate (naloxone insensitive) in a dose-dependent manner (concentration producing 50% inhibition approximately 2 mM) in all cell lines, including untransfected CHO cells. Ketamine (100 microM) reversed DAMGO (mu) and spiradoline (kappa) inhibition of formation of cyclic adenosine monophosphate. Conclusions Ketamine interacts stereoselectively with recombinant mu and kappa opioid receptors.

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Priming innate immune responses to infection by cyclooxygenase inhibition kills antibiotic-susceptible and -resistant bacteria

Blood ◽

10.1182/blood-2010-05-284844 ◽

2010 ◽

Vol 116 (16) ◽

pp. 2950-2959 ◽

Cited By ~ 38

Author(s):

Melanie J. Stables ◽

Justine Newson ◽

Samir S. Ayoub ◽

Jeremy Brown ◽

Catherine J. Hyams ◽

...

Keyword(s):

Antibiotic Resistance ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Innate Immune ◽

Host Responses ◽

Resistant Bacteria ◽

Reactive Oxygen Intermediate ◽

Dependent Manner ◽

Bacterial Killing ◽

Relative Contribution

AbstractInhibition of cyclooxygenase (COX)–derived prostaglandins (PGs) by nonsteroidal anti-inflammatory drugs (NSAIDs) mediates leukocyte killing of bacteria. However, the relative contribution of COX1 versus COX2 to this process, as well as the mechanisms controlling it in mouse and humans, are unknown. Indeed, the potential of NSAIDs to facilitate leukocyte killing of drug-resistant bacteria warrants investigation. Therefore, we carried out a series of experiments in mice and humans, finding that COX1 is the predominant isoform active in PG synthesis during infection and that its prophylactic or therapeutic inhibition primes leukocytes to kill bacteria by increasing phagocytic uptake and reactive oxygen intermediate-mediated killing in a cyclic adenosine monophosphate (cAMP)-dependent manner. Moreover, NSAIDs enhance bacterial killing in humans, exerting an additive effect when used in combination with antibiotics. Finally, NSAIDs, through the inhibition of COX prime the innate immune system to mediate bacterial clearance of penicillin-resistant Streptococcus pneumoniae serotype 19A, a well-recognized vaccine escape serotype of particular concern given its increasing prevalence and multi-antibiotic resistance. Therefore, these data underline the importance of lipid mediators in host responses to in-fection and the potential of inhibitors of PG signaling pathways as adjunc-tive therapies, particularly in the con-text of antibiotic resistance.

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Epidermal growth factor stimulates the prolactin synthesis and secretion in rat pituitary cells in culture (GH4C1 cells) by increasing the intracellular concentration of free calcium

Acta Endocrinologica ◽

10.1530/acta.0.1280361 ◽

1993 ◽

Vol 128 (4) ◽

pp. 361-366 ◽

Cited By ~ 11

Author(s):

Marie Aanestad ◽

J Sigurd Røtnes ◽

Peter A Torjesen ◽

Egil Haug ◽

Olav Sand ◽

...

Keyword(s):

Growth Factor ◽

Epidermal Growth Factor ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Intracellular Concentration ◽

Free Calcium ◽

Pituitary Cells ◽

Maximal Effect ◽

Dependent Manner ◽

Epidermal Growth

Epidermal growth factor (EGF) stimulated the prolactin (PRL) synthesis and release from the GH4C1 cells in a dose-dependent manner. The ED50 was between 10−11 and 10−10 mol/l. The maximal effect was obtained at 10−9 mol/l EGF for the release, and 10−8 mol/l EGF for the synthesis. EGF stimulated the release of PRL from cell perfusion columns after a lag period of about 30 s. The maximal secretion of PRL occurred about 60 s after the start of stimulation. The PRL secretion declined to basal levels within 2 min. The EGF-stimulated PRL release was additive to the secretion evoked by thyrotropin-releasing hormone (TRH) and vasoactive intestinal peptide (VIP). An instantaneous increase in the intracellular concentration of free calcium, [Ca2+]i, of the GH4C1 cells was observed after the administration of EGF. EGF modified neither the basal nor the TRH-stimulated inositoltrisphosphate production in the GH4C1 cells, and EGF did not show any effect on the cyclic adenosine monophosphate production of these cells.

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Calcitonin gene-related peptide down-regulates bleomycin-induced pulmonary fibrosis

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2015-0602 ◽

2016 ◽

Vol 94 (12) ◽

pp. 1315-1324 ◽

Cited By ~ 8

Author(s):

Xian-Wei Li ◽

Xiao-Hui Li ◽

Jie Du ◽

Dai Li ◽

Yuan-Jian Li ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Calcitonin Gene Related Peptide ◽

Collagen I ◽

Lung Fibroblasts ◽

Brdu Incorporation ◽

Pulmonary Fibroblasts ◽

Related Peptide ◽

Calcitonin Gene ◽

Collagen Iii ◽

Tgf Β1

We have found that eIF3a plays an important role in bleomycin-induced pulmonary fibrosis, and up-regulation of eIF3a induced by TGF-β1 is mediated via the ERK1/2 pathway. Whether ERK1/2 – eIF3a signal pathway is involved in calcitonin gene-related peptide (CGRP)-mediated pathogenesis of bleomycin-induced pulmonary fibrosis remains unknown. Pulmonary fibrosis was induced by intratracheal instillation of bleomycin (5 mg/kg) in rats. Primary pulmonary fibroblasts were cultured to investigate the proliferation by BrdU incorporation method and flow cytometry. Sensory CGRP depletion by capsaicin exacerbated bleomycin-induced pulmonary fibrosis in rats, as shown by a significant disturbed alveolar structure, marked thickening of the interalveolar septa and dense interstitial infiltration by inflammatory cells and fibroblasts, accompanied with increased expression of TGF-β1, eIF3a, phosphorylated ERK1/2, α-SMA, collagen I, and collagen III. Exogenous application of CGRP significantly inhibited TGF-β1-induced proliferation and differentiation of pulmonary fibroblasts concomitantly with decreased expression of eIF3a, phosphorylated ERK1/2, α-SMA, collagen I, and collagen III. These effects of CGRP were abolished in the presence of CGRP8-37. These results suggest that endogenous CGRP is related to the development of pulmonary fibrosis induced by bleomycin, and the inhibitory effect of CGRP on proliferation of lung fibroblasts involves the ERK1/2 – eIF3a signaling pathway.

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Citrullinated vimentin mediates development and progression of lung fibrosis

Science Translational Medicine ◽

10.1126/scitranslmed.aba2927 ◽

2021 ◽

Vol 13 (585) ◽

pp. eaba2927

Author(s):

Fu Jun Li ◽

Ranu Surolia ◽

Huashi Li ◽

Zheng Wang ◽

Gang Liu ◽

...

Keyword(s):

Lung Tissue ◽

Lung Fibrosis ◽

Ex Vivo ◽

Lavage Fluid ◽

Surface Expression ◽

Lung Fibroblasts ◽

Dependent Manner ◽

Ex Vivo Model ◽

Molecular Pattern ◽

Citrullinated Vimentin

The mechanisms by which environmental exposures contribute to the pathogenesis of lung fibrosis are unclear. Here, we demonstrate an increase in cadmium (Cd) and carbon black (CB), common components of cigarette smoke (CS) and environmental particulate matter (PM), in lung tissue from subjects with idiopathic pulmonary fibrosis (IPF). Cd concentrations were directly proportional to citrullinated vimentin (Cit-Vim) amounts in lung tissue of subjects with IPF. Cit-Vim amounts were higher in subjects with IPF, especially smokers, which correlated with lung function and were associated with disease manifestations. Cd/CB induced the secretion of Cit-Vim in an Akt1- and peptidylarginine deiminase 2 (PAD2)–dependent manner. Cit-Vim mediated fibroblast invasion in a 3D ex vivo model of human pulmospheres that resulted in higher expression of CD26, collagen, and α-SMA. Cit-Vim activated NF-κB in a TLR4-dependent fashion and induced the production of active TGF-β1, CTGF, and IL-8 along with higher surface expression of TLR4 in lung fibroblasts. To corroborate ex vivo findings, mice treated with Cit-Vim, but not Vim, independently developed a similar pattern of fibrotic tissue remodeling, which was TLR4 dependent. Moreover, wild-type mice, but not PAD2−/− and TLR4 mutant (MUT) mice, exposed to Cd/CB generated high amounts of Cit-Vim, in both plasma and bronchoalveolar lavage fluid, and developed lung fibrosis in a stereotypic manner. Together, these studies support a role for Cit-Vim as a damage-associated molecular pattern molecule (DAMP) that is generated by lung macrophages in response to environmental Cd/CB exposure. Furthermore, PAD2 might represent a promising target to attenuate Cd/CB-induced fibrosis.

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