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Ball L, Bauer J, Krautwurst D. Heterodimerization of Chemoreceptors TAS1R3 and mGlu 2 in Human Blood Leukocytes. Int J Mol Sci 2023; 24:12942. [PMID: 37629122 PMCID: PMC10454557 DOI: 10.3390/ijms241612942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/08/2023] [Accepted: 08/15/2023] [Indexed: 08/27/2023] Open
Abstract
The expression of canonical chemosensory receptors of the tongue, such as the heteromeric sweet taste (TAS1R2/TAS1R3) and umami taste (TAS1R1/TAS1R3) receptors, has been demonstrated in many extra-oral cells and tissues. Gene expression studies have revealed transcripts for all TAS1 and metabotropic glutamate (mGlu) receptors in different types of immune cells, where they are involved, for example, in the chemotaxis of human neutrophils and the protection of T cells from activation-induced cell death. Like other class-C G protein-coupling receptors (GPCRs), TAS1Rs and mGlu receptors form heteromers within their families. Since mGlu receptors and TAS1R1/TAS1R3 share the same ligand, monosodium glutamate (MSG), we hypothesized their hitherto unknown heteromerization across receptor families in leukocytes. Here we show, by means of immunocytochemistry and co-IP/Western analysis, that across class-C GPCR families, mGlu2 and TAS1R3 co-localize and heterodimerize in blood leukocytes. Expressing the recombinant receptors in HEK-293 cells, we validated their heterodimerization by bioluminescence resonance energy transfer. We demonstrate MSG-induced, mGlu2/TAS1R3 heteromer-dependent gain-of-function and pertussis toxin-sensitive signaling in luminescence assays. Notably, we show that mGlu2/TAS1R3 is necessary and sufficient for MSG-induced facilitation of N-formyl-methionyl-leucyl-phenylalanine-stimulated IL-8 secretion in neutrophils, using receptor-specific antagonists. In summary, our results demonstrate mGlu2/TAS1R3 heterodimerization in leukocytes, suggesting cellular function-tailored chemoreceptor combinations to modulate cellular immune responses.
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Affiliation(s)
- Lena Ball
- TUM School of Life Sciences, Technical University of Munich, Alte Akademie 8a, 85354 Freising, Germany;
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany;
| | - Julia Bauer
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany;
| | - Dietmar Krautwurst
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany;
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2
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Kubatzky KF. Pasteurella multocida toxin - lessons learned from a mitogenic toxin. Front Immunol 2022; 13:1058905. [PMID: 36591313 PMCID: PMC9800868 DOI: 10.3389/fimmu.2022.1058905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
The gram-negative, zoonotic bacterium Pasteurella multocida was discovered in 1880 and found to be the causative pathogen of fowl cholera. Pasteurella-related diseases can be found in domestic and wild life animals such as buffalo, sheep, goat, deer and antelope, cats, dogs and tigers and cause hemorrhagic septicemia in cattle, rhinitis or pneumonia in rabbits or fowl cholera in poultry and birds. Pasteurella multocida does not play a major role in the immune-competent human host, but can be found after animal bites or in people with close contact to animals. Toxigenic strains are most commonly found in pigs and express a phage-encoded 146 kDa protein, the Pasteurella multocida toxin (PMT). Toxin-expressing strains cause atrophic rhinitis where nasal turbinate bones are destroyed through the inhibition of bone building osteoblasts and the activation of bone resorbing osteoclasts. After its uptake through receptor-mediated endocytosis, PMT specifically targets the alpha subunit of several heterotrimeric G proteins and constitutively activates them through deamidation of a glutamine residue to glutamate in the alpha subunit. This results in cytoskeletal rearrangement, proliferation, differentiation and survival of cells. Because of the toxin's mitogenic effects, it was suggested that it might have carcinogenic properties, however, no link between Pasteurella infections and cell transformation could be established, neither in tissue culture models nor through epidemiological data. In the recent years it was shown that the toxin not only affects bone, but also the heart as well as basically all cells of innate and adaptive immunity. During the last decade the focus of research shifted from signal transduction processes to understanding how the bacteria might benefit from a bone-destroying toxin. The primary function of PMT seems to be the modulation of immune cell activation which at the same time creates an environment permissive for osteoclast formation. While the disease is restricted to pigs, the implications of the findings from PMT research can be used to explore human diseases and have a high translational potential. In this review our current knowledge will be summarized and it will be discussed what can be learned from using PMT as a tool to understand human pathologies.
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Affiliation(s)
- Katharina F. Kubatzky
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
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Holdfeldt A, Lind S, Hesse C, Dahlgren C, Forsman H. The PAR4-derived pepducin P4Pal 10 lacks effect on neutrophil GPCRs that couple to Gαq for signaling but distinctly modulates function of the Gαi-coupled FPR2 and FFAR2. Biochem Pharmacol 2020; 180:114143. [PMID: 32653592 DOI: 10.1016/j.bcp.2020.114143] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/03/2020] [Accepted: 07/07/2020] [Indexed: 12/18/2022]
Abstract
A novel mechanism of action was described for the protease-activated receptor 4 (PAR4)-derived pepducin (P4Pal10), when it was shown to exhibit inhibitory efficacy towards G protein coupling to multiple Gαq-coupled receptors (Carr, R., 3rd et al., Mol. Pharmacol. 2016(89) 94). We could confirm that P4Pal10, similar to an earlier-characterized Gαq inhibitor (YM-254890), inhibited platelet aggregation induced by agonists for the Gαq-coupled receptors PAR1 and PAR4. Next, we applied P4Pal10 as a tool compound and investigated its modulatory effect on several Gαq- and Gαi-coupled GPCRs expressed by human neutrophils. P4Pal10 had, however, no inhibitory effects on signaling downstream of the Gαq-coupled receptors for ATP (P2Y2R) and PAF (PAFR). Instead, P4Pal10 inhibited signaling downstream the Gαi-coupled FPR2. The inhibition was not due to a direct effect on Gαi as the closely related FPR1 was unaffected. In addition, we found that the pepducin activated allosterically modulated short chain fatty acid receptor (FFAR2), a Gαi/Gαq coupled GPCR that is functionally expressed in neutrophils. Taken together, we show that pepducins are unique tool-compounds for mechanistic studies of GPCR signaling and modulation in neutrophils. The data presented add also lipopeptides into the known ligand recognition lists for the two pattern recognition receptors FPR2 and FFAR2, receptors that primarily sense formylated peptides and short free fatty acids, respectively, inflammatory mediators of microbial origin.
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Affiliation(s)
- André Holdfeldt
- Department of Rheumatology and Inflammation Research, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Simon Lind
- Department of Rheumatology and Inflammation Research, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Camilla Hesse
- Department for Laboratory Medicine, Institute for Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Claes Dahlgren
- Department of Rheumatology and Inflammation Research, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Huamei Forsman
- Department of Rheumatology and Inflammation Research, Institute of Medicine at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Holdfeldt A, Dahlstrand Rudin A, Gabl M, Rajabkhani Z, König GM, Kostenis E, Dahlgren C, Forsman H. Reactivation of Gαi‐coupled formyl peptide receptors is inhibited by Gαq‐selective inhibitors when induced by signals generated by the platelet‐activating factor receptor. J Leukoc Biol 2017; 102:871-880. [DOI: 10.1189/jlb.2a0317-086rr] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/08/2017] [Accepted: 06/12/2017] [Indexed: 12/12/2022] Open
Affiliation(s)
- André Holdfeldt
- Department of Rheumatology and Inflammation Research, University of Gothenburg, Gothenburg, Sweden
| | - Agnes Dahlstrand Rudin
- Department of Oral Microbiology and Immunology, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; and
| | - Michael Gabl
- Department of Rheumatology and Inflammation Research, University of Gothenburg, Gothenburg, Sweden
| | - Zahra Rajabkhani
- Department of Rheumatology and Inflammation Research, University of Gothenburg, Gothenburg, Sweden
| | - Gabriele M. König
- Molecular, Cellular and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany
| | - Evi Kostenis
- Molecular, Cellular and Pharmacobiology Section, Institute of Pharmaceutical Biology, University of Bonn, Bonn, Germany
| | - Claes Dahlgren
- Department of Rheumatology and Inflammation Research, University of Gothenburg, Gothenburg, Sweden
| | - Huamei Forsman
- Department of Rheumatology and Inflammation Research, University of Gothenburg, Gothenburg, Sweden
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Celik MÖ, Labuz D, Henning K, Busch-Dienstfertig M, Gaveriaux-Ruff C, Kieffer BL, Zimmer A, Machelska H. Leukocyte opioid receptors mediate analgesia via Ca(2+)-regulated release of opioid peptides. Brain Behav Immun 2016; 57:227-242. [PMID: 27139929 DOI: 10.1016/j.bbi.2016.04.018] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 12/23/2022] Open
Abstract
Opioids are the most powerful analgesics. As pain is driven by sensory transmission and opioid receptors couple to inhibitory G proteins, according to the classical concept, opioids alleviate pain by activating receptors on neurons and blocking the release of excitatory mediators (e.g., substance P). Here we show that analgesia can be mediated by opioid receptors in immune cells. We propose that activation of leukocyte opioid receptors leads to the secretion of opioid peptides Met-enkephalin, β-endorphin and dynorphin A (1-17), which subsequently act at local neuronal receptors, to relieve pain. In a mouse model of neuropathic pain induced by a chronic constriction injury of the sciatic nerve, exogenous agonists of δ-, μ- and κ-opioid receptors injected at the damaged nerve infiltrated by opioid peptide- and receptor-expressing leukocytes, produced analgesia, as assessed with von Frey filaments. The analgesia was attenuated by pharmacological or genetic inactivation of opioid peptides, and by leukocyte depletion. This decrease in analgesia was restored by the transfer of wild-type, but not opioid receptor-lacking leukocytes. Ex vivo, exogenous opioids triggered secretion of opioid peptides from wild-type immune cells isolated from damaged nerves, which was diminished by blockade of Gαi/o or Gβγ (but not Gαs) proteins, by chelator of intracellular (but not extracellular) Ca(2+), by blockers of phospholipase C (PLC) and inositol 1,4,5-trisphosphate (IP3) receptors, and was partially attenuated by protein kinase C inhibitor. Similarly, the leukocyte depletion-induced decrease in exogenous opioid analgesia was re-established by transfer of immune cells ex vivo pretreated with extracellular Ca(2+) chelator, but was unaltered by leukocytes pretreated with intracellular Ca(2+) chelator or blockers of Gαi/o and Gβγ proteins. Thus, both ex vivo opioid peptide release and in vivo analgesia were mediated by leukocyte opioid receptors coupled to the Gαi/o-Gβγ protein-PLC-IP3 receptors-intracellular Ca(2+) pathway. Our findings suggest that opioid receptors in immune cells are important targets for the control of pathological pain.
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Affiliation(s)
- Melih Ö Celik
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany.
| | - Dominika Labuz
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany.
| | - Karen Henning
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany.
| | - Melanie Busch-Dienstfertig
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany.
| | - Claire Gaveriaux-Ruff
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France; Université de Strasbourg, Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.
| | - Brigitte L Kieffer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France; Université de Strasbourg, Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France; Douglas Hospital Research Center, McGill University, Montreal H4H 1R3, Canada.
| | - Andreas Zimmer
- Institute of Molecular Psychiatry, University of Bonn, 53105 Bonn, Germany.
| | - Halina Machelska
- Department of Anesthesiology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany.
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Geithe C, Andersen G, Malki A, Krautwurst D. A Butter Aroma Recombinate Activates Human Class-I Odorant Receptors. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:9410-9420. [PMID: 26451762 DOI: 10.1021/acs.jafc.5b01884] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
With ∼400 olfactory G protein-coupled receptors (GPCR), humans sensitively perceive ∼230 key aroma compounds as best natural agonists of ∼10000 food volatiles. An understanding of odorant coding, thus, critically depends on the knowledge about interactions of key food aroma chemicals and their mixtures with their cognate receptors. Genetically designed test cell systems enable the screening, deorphaning, and characterization of single odorant receptors (OR). This study shows for the food aroma-specific and quantitative butter aroma recombinate, and its single components, specific in vitro class-I OR activity patterns, as well as the activation of selected OR in a concentration-dependent manner. Recently, chemosensory receptors, especially class-I OR, were demonstrated to be expressed on blood leukocytes, which may encounter foodborne aroma compounds postprandially. This study shows that butter aroma recombinate induced chemotaxis of isolated human neutrophils in a defined gradient, and in a concentration-dependent and pertussis toxin-sensitive manner, suggesting at least a GPCR-mediated activation of blood leukocytes by key food odorants.
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Affiliation(s)
- Christiane Geithe
- Deutsche Forschungsanstalt fuer Lebensmittelchemie Leibniz Institut, Lise-Meitner-Strasse 34, 85354 Freising, Germany
| | - Gaby Andersen
- Deutsche Forschungsanstalt fuer Lebensmittelchemie Leibniz Institut, Lise-Meitner-Strasse 34, 85354 Freising, Germany
| | - Agne Malki
- Deutsche Forschungsanstalt fuer Lebensmittelchemie Leibniz Institut, Lise-Meitner-Strasse 34, 85354 Freising, Germany
| | - Dietmar Krautwurst
- Deutsche Forschungsanstalt fuer Lebensmittelchemie Leibniz Institut, Lise-Meitner-Strasse 34, 85354 Freising, Germany
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7
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Malki A, Fiedler J, Fricke K, Ballweg I, Pfaffl MW, Krautwurst D. Class I odorant receptors, TAS1R and TAS2R taste receptors, are markers for subpopulations of circulating leukocytes. J Leukoc Biol 2015; 97:533-45. [PMID: 25624459 DOI: 10.1189/jlb.2a0714-331rr] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Our cellular immune system has to cope constantly with foodborne substances that enter the bloodstream postprandially. Here, they may activate leukocytes via specific but yet mostly unknown receptors. Ectopic RNA expression out of gene families of chemosensory receptors, i.e., the ∼400 ORs, ∼25 TAS2R bitter-taste receptors, and the TAS1R umami- and sweet-taste receptor dimers by which we typically detect foodborne substances, has been reported in a variety of peripheral tissues unrelated to olfaction or taste. In the present study, we have now discovered, by gene-specific RT-PCR experiments, the mRNA expression of most of the Class I ORs (TAS1R) and TAS2R in 5 different types of blood leukocytes. Surprisingly, we did not detect Class II OR mRNA. By RT-qPCR, we show the mRNA expression of human chemosensory receptors and their cow orthologs in PMN, thus suggesting an evolutionary concept. By immunocytochemistry, we demonstrate that some olfactory and taste receptors are expressed, on average, in 40-60% of PMN and T or B cells and largely coexpress in the same subpopulation of PMN. The mRNA expression and the size of subpopulations expressing certain chemosensory receptors varied largely among individual blood samples, suggesting a regulated expression of olfactory and taste receptors in these cells. Moreover, we show mRNA expression of their downstream signaling molecules and demonstrate that PTX abolishes saccharin- or 2-PEA-induced PMN chemotactic migration, indicating a role for Gi-type proteins. In summary, our data suggest "chemosensory"-type subpopulations of circulating leukocytes.
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Affiliation(s)
- Agne Malki
- *Deutsche Forschungsanstalt für Lebensmittelchemie Leibniz Institute, Freising, Germany; and Technische Universität München, Lehrstuhl für Physiologie-Wissenschaftszentrum Weihenstephan, Freising, Germany
| | - Julia Fiedler
- *Deutsche Forschungsanstalt für Lebensmittelchemie Leibniz Institute, Freising, Germany; and Technische Universität München, Lehrstuhl für Physiologie-Wissenschaftszentrum Weihenstephan, Freising, Germany
| | - Kristina Fricke
- *Deutsche Forschungsanstalt für Lebensmittelchemie Leibniz Institute, Freising, Germany; and Technische Universität München, Lehrstuhl für Physiologie-Wissenschaftszentrum Weihenstephan, Freising, Germany
| | - Ines Ballweg
- *Deutsche Forschungsanstalt für Lebensmittelchemie Leibniz Institute, Freising, Germany; and Technische Universität München, Lehrstuhl für Physiologie-Wissenschaftszentrum Weihenstephan, Freising, Germany
| | - Michael W Pfaffl
- *Deutsche Forschungsanstalt für Lebensmittelchemie Leibniz Institute, Freising, Germany; and Technische Universität München, Lehrstuhl für Physiologie-Wissenschaftszentrum Weihenstephan, Freising, Germany
| | - Dietmar Krautwurst
- *Deutsche Forschungsanstalt für Lebensmittelchemie Leibniz Institute, Freising, Germany; and Technische Universität München, Lehrstuhl für Physiologie-Wissenschaftszentrum Weihenstephan, Freising, Germany
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Griffiths KL, Stylianou E, Poyntz HC, Betts GJ, Fletcher HA, McShane H. Cholera toxin enhances vaccine-induced protection against Mycobacterium tuberculosis challenge in mice. PLoS One 2013; 8:e78312. [PMID: 24194918 PMCID: PMC3806838 DOI: 10.1371/journal.pone.0078312] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 09/13/2013] [Indexed: 12/20/2022] Open
Abstract
Interleukin (IL)-17 is emerging as an important cytokine in vaccine-induced protection against tuberculosis disease in animal models. Here we show that compared to parenteral delivery, BCG delivered mucosally enhances cytokine production, including interferon gamma and IL-17, in the lungs. Furthermore, we find that cholera toxin, delivered mucosally along with BCG, further enhances IL-17 production by CD4(+) T cells over mucosal BCG alone both in the lungs and systemically. This boosting effect of CT is also observed using a vaccine regimen of BCG followed by the candidate vaccine MVA85A. Using a murine Mycobacterium tuberculosis (M.tb) aerosol challenge model, we demonstrate the ability of cholera toxin delivered at the time of a priming BCG vaccination to improve protection against tuberculosis disease in a manner at least partially dependent on the observed increase in IL-17. This observed increase in IL-17 in the lungs has no adverse effect on lung pathology following M.tb challenge, indicating that IL-17 can safely be boosted in murine lungs in a vaccine/M.tb challenge setting.
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Affiliation(s)
| | - Elena Stylianou
- Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Hazel C. Poyntz
- Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Gareth J. Betts
- Jenner Institute, University of Oxford, Oxford, United Kingdom
| | | | - Helen McShane
- Jenner Institute, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Sunkara LT, Zeng X, Curtis AR, Zhang G. Cyclic AMP synergizes with butyrate in promoting β-defensin 9 expression in chickens. Mol Immunol 2013; 57:171-80. [PMID: 24141182 DOI: 10.1016/j.molimm.2013.09.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 09/19/2013] [Accepted: 09/21/2013] [Indexed: 10/26/2022]
Abstract
Host defense peptides (HDP) have both microbicidal and immunomodulatory properties. Specific induction of endogenous HDP synthesis has emerged as a novel approach to antimicrobial therapy. Cyclic adenosine monophosphate (cAMP) and butyrate have been implicated in HDP induction in humans. However, the role of cAMP signaling and the possible interactions between cAMP and butyrate in regulating HDP expression in other species remain unknown. Here we report that activation of cAMP signaling induces HDP gene expression in chickens as exemplified by β-defensin 9 (AvBD9). We further showed that, albeit being weak inducers, cAMP agonists synergize strongly with butyrate or butyrate analogs in AvBD9 induction in macrophages and primary jejunal explants. Additionally, oral supplementation of forskolin, an adenylyl cyclase agonist in the form of a Coleus forskohlii extract, was found to induce AvBD9 expression in the crop of chickens. Furthermore, feeding with both forskolin and butyrate showed an obvious synergy in triggering AvBD9 expression in the crop and jejunum of chickens. Surprisingly, inhibition of the MEK-ERK mitogen-activated protein kinase (MAPK) pathway augmented the butyrate-FSK synergy, whereas blocking JNK or p38 MAPK pathway significantly diminished AvBD9 induction in chicken macrophages and jejunal explants in response to butyrate and FSK individually or in combination. Collectively, these results suggest the potential for concomitant use of butyrate and cAMP signaling activators in enhancing HDP expression, innate immunity, and disease resistance in both animals and humans.
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Affiliation(s)
- Lakshmi T Sunkara
- Department of Animal Science, Oklahoma State University, Stillwater, OK 74078, USA
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