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Acetylcholine levels and cholinergic mechanisms in PRiMA deficient mice
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Abstracts / Autonomic Neuroscience: Basic and Clinical 177 (2013) 1–65
functional role of these brush cells, and of ACh in particular, in chemosensation in health and disease. doi:10.1016/j.autneu.2013.05.140
Poster 20.15 Acetylcholine levels and cholinergic mechanisms in PRiMA deficient mice F. Mohr (Department of Pharmacology, Goethe University, Frankfurt, Germany), E. Krejci (Université Paris Descartes CNRS UMR 8194, Paris, France), M. Zimmermann, J. Klein (Department of Pharmacology, Goethe University, Frankfurt, Germany) The proline-rich membrane anchor (PRiMA), a transmembrane protein, directs acetylcholinesterase (AChE) to the cell surface and organizes AChE into its tetrameric and functional form. In PRiMA KO mice striatal AChE activity is decreased to less than 10% of wild type (WT) activity. As cholinergic dysfunction plays a major role in a variety of diseases (e.g. Alzheimer’s disease, Myasthenia gravis), it is of general interest how AChE activity is regulated and if PRiMA may be a new target for the treatment of cholinergic dysfunction. In the present study, we analyzed extracellular striatal and hippocampal acetylcholine (ACh) levels in PRiMA KO mice. ACh samples were collected by in vivo microdialysis in awake mice. Samples were analyzed for ACh by HPLC. Basal levels in the striatum of ACh in WT mice were 3.5 ± 2.5 fmol/5 μl. In PRiMA KO mice, ACh levels were dramatically increased by 350fold (1446 ± 704 fmol/5 μl; N ≥ 22 each). Intrastriatal infusion of the specific AChE inhibitor BW284c51 caused a rise of ACh levels in both WT and KO mice. No modifications of ACh levels were detected after treatment with the specific BChE inhibitor bambuterol suggesting that BChE does not play a major role in adaptive mechanisms. Although ACh levels are extremely high and can be further raised by AChE inhibitors, PRiMA KO mice do not show any noticeable phenotype. In further experiments, a dysfunction of muscarinic M2 receptors was revealed by intrastriatal infusion of the muscarinic agonist, oxotremorine (100 μM). Behavior tests indicate that PRiMA KO mice do not have altered cognitive function. Our findings of dramatically increased ACh levels in PRiMA KO mice, in the absence of an overt phenotype, suggest that inhibition of the PRiMA-AChE interaction by drugs may compensate for central cholinergic dysfunction in the absence of serious side effects. doi:10.1016/j.autneu.2013.05.141
Poster 20.17 Chronic skin inflammation is associated with functionally relevant NNCS changes in the skin Eva M.J. Peters (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany), Anna V. Michenko (Department of Dermatology, University Hospital Giessen, Giessen, Germany), Jörg Kupfer (Institute of Medical Psychology, Justus-Liebig University, Giessen, Germany), Wolfgang Kummer (Institute of Anatomy and Cell Biology, JustusLiebig-University, Giessen, Germany), Susanne Tumala, Badrinarayanan Raghavan (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany), Uwe Gieler (Department of Dermatology, University Hospital Giessen, Giessen, Germany)
The stress response to inflammatory as well as psychoemotional challenges may involve cholinergic signaling not only on a systemic level but also locally in peripheral tissues. Here we investigate the effect of a short and rather acute psychoemotional stress challenge (Trier Social Stress Test [TSST]) on neuro-immune plasticity and members of the non-neuronal cholinergic system (NNCS) of the skin in patients with atopic dermatitis (AD) compared to skin-healthy controls. Immunohistomorphometry (IHM) of nerve fiber-density and -immune contacts revealed that lesional skin of AD patients compared to healthy control skin showed significantly higher numbers of PGP 9-5+ nerve fibers and lower numbers of tryptase+ mast cells in the upper dermis. After stress reduced nerve fiber numbers were accompanied by decreased neuronal-plasticity (Gap43 and NGF IHM) and decreased neuro-immune contacts between PGP 9.5+ nerve fibers and mast cells solely in lesional AD skin while in non-lesional AD skin, nerve-mast cell contacts showed a tendency to increased numbers. By quantitative RT-PCR we found that α7nAChR level was lower in AD skin than in controls and that stress showed a tendency to increase it solely in lesional AD skin. At the same time, α3nAChR level was lower in non-lesional and higher in lesional AD skin compared to controls and stress decreased it in healthy skin while it was increased it in AD skin. Secreted mammal Ly-6/ urokinase-type plasminogen activator receptor-related protein (SLURP) 1 (endogenous α7nAChR ligand) mRNA level was lower in non-lesional AD than in healthy controls and SLURP-2 (endogenous α3nAChR ligand) showed a like tendency while lesional AD skin did not show much difference to control. After stress, the expression of SLURP-1 and -2 decreased in healthy skin but increased in lesional AD skin. By contrast, in non-lesional AD skin after stress SLURP levels remained low. Clinical/pathological outcome parameters revealed highest epidermal thickness in lesional AD skin which was reduced after stress experience along with improved disease activity as assessed by the SCORAD. By contrast, in non-lesional AD skin, along with the described tendency towards higher numbers of nerve-mast cell contacts, epidermal thickness was increased after stress along with a tendency towards higher itch perception. We conclude that psychoemotional stress has differential NNCS effects in healthy and AD skin with pro-inflammatory effects in not yet affected skin and anti-inflammatory effects in inflamed skin. doi:10.1016/j.autneu.2013.05.142
Poster 20.18 Stress alters cytokine profile of the skin: prospective links to stress-induced NNCS regulation in skin Frank Risto Rommel, Badrinarayanan Raghavan, Susanne Tumala (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany), Uwe Gieler (Department of Dermatology, University Hospital Giessen, Giessen, Germany), Eva M.J. Peters (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany) Organs at the self-environment interface are confronted with a plethora of exogenous and endogenous challenges. Adaptation to these challenges appears to be a distinct feature of the cholinergic system. The skin is known to possess an intrinsically acting stresscascade, in which acetylcholine may play a vital role in the regulation of peripheral inflammation and disease. Thus it is essential to address the role of stress perception and subsequent non-neuronal cholinergic system (NNCS) induced modulation of the skin in response to different kinds of stressors. By microarray analysis we compared skin
Abstracts / Autonomic Neuroscience: Basic and Clinical 177 (2013) 1–65
functional role of these brush cells, and of ACh in particular, in chemosensation in health and disease. doi:10.1016/j.autneu.2013.05.140
Poster 20.15 Acetylcholine levels and cholinergic mechanisms in PRiMA deficient mice F. Mohr (Department of Pharmacology, Goethe University, Frankfurt, Germany), E. Krejci (Université Paris Descartes CNRS UMR 8194, Paris, France), M. Zimmermann, J. Klein (Department of Pharmacology, Goethe University, Frankfurt, Germany) The proline-rich membrane anchor (PRiMA), a transmembrane protein, directs acetylcholinesterase (AChE) to the cell surface and organizes AChE into its tetrameric and functional form. In PRiMA KO mice striatal AChE activity is decreased to less than 10% of wild type (WT) activity. As cholinergic dysfunction plays a major role in a variety of diseases (e.g. Alzheimer’s disease, Myasthenia gravis), it is of general interest how AChE activity is regulated and if PRiMA may be a new target for the treatment of cholinergic dysfunction. In the present study, we analyzed extracellular striatal and hippocampal acetylcholine (ACh) levels in PRiMA KO mice. ACh samples were collected by in vivo microdialysis in awake mice. Samples were analyzed for ACh by HPLC. Basal levels in the striatum of ACh in WT mice were 3.5 ± 2.5 fmol/5 μl. In PRiMA KO mice, ACh levels were dramatically increased by 350fold (1446 ± 704 fmol/5 μl; N ≥ 22 each). Intrastriatal infusion of the specific AChE inhibitor BW284c51 caused a rise of ACh levels in both WT and KO mice. No modifications of ACh levels were detected after treatment with the specific BChE inhibitor bambuterol suggesting that BChE does not play a major role in adaptive mechanisms. Although ACh levels are extremely high and can be further raised by AChE inhibitors, PRiMA KO mice do not show any noticeable phenotype. In further experiments, a dysfunction of muscarinic M2 receptors was revealed by intrastriatal infusion of the muscarinic agonist, oxotremorine (100 μM). Behavior tests indicate that PRiMA KO mice do not have altered cognitive function. Our findings of dramatically increased ACh levels in PRiMA KO mice, in the absence of an overt phenotype, suggest that inhibition of the PRiMA-AChE interaction by drugs may compensate for central cholinergic dysfunction in the absence of serious side effects. doi:10.1016/j.autneu.2013.05.141
Poster 20.17 Chronic skin inflammation is associated with functionally relevant NNCS changes in the skin Eva M.J. Peters (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany), Anna V. Michenko (Department of Dermatology, University Hospital Giessen, Giessen, Germany), Jörg Kupfer (Institute of Medical Psychology, Justus-Liebig University, Giessen, Germany), Wolfgang Kummer (Institute of Anatomy and Cell Biology, JustusLiebig-University, Giessen, Germany), Susanne Tumala, Badrinarayanan Raghavan (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany), Uwe Gieler (Department of Dermatology, University Hospital Giessen, Giessen, Germany)
The stress response to inflammatory as well as psychoemotional challenges may involve cholinergic signaling not only on a systemic level but also locally in peripheral tissues. Here we investigate the effect of a short and rather acute psychoemotional stress challenge (Trier Social Stress Test [TSST]) on neuro-immune plasticity and members of the non-neuronal cholinergic system (NNCS) of the skin in patients with atopic dermatitis (AD) compared to skin-healthy controls. Immunohistomorphometry (IHM) of nerve fiber-density and -immune contacts revealed that lesional skin of AD patients compared to healthy control skin showed significantly higher numbers of PGP 9-5+ nerve fibers and lower numbers of tryptase+ mast cells in the upper dermis. After stress reduced nerve fiber numbers were accompanied by decreased neuronal-plasticity (Gap43 and NGF IHM) and decreased neuro-immune contacts between PGP 9.5+ nerve fibers and mast cells solely in lesional AD skin while in non-lesional AD skin, nerve-mast cell contacts showed a tendency to increased numbers. By quantitative RT-PCR we found that α7nAChR level was lower in AD skin than in controls and that stress showed a tendency to increase it solely in lesional AD skin. At the same time, α3nAChR level was lower in non-lesional and higher in lesional AD skin compared to controls and stress decreased it in healthy skin while it was increased it in AD skin. Secreted mammal Ly-6/ urokinase-type plasminogen activator receptor-related protein (SLURP) 1 (endogenous α7nAChR ligand) mRNA level was lower in non-lesional AD than in healthy controls and SLURP-2 (endogenous α3nAChR ligand) showed a like tendency while lesional AD skin did not show much difference to control. After stress, the expression of SLURP-1 and -2 decreased in healthy skin but increased in lesional AD skin. By contrast, in non-lesional AD skin after stress SLURP levels remained low. Clinical/pathological outcome parameters revealed highest epidermal thickness in lesional AD skin which was reduced after stress experience along with improved disease activity as assessed by the SCORAD. By contrast, in non-lesional AD skin, along with the described tendency towards higher numbers of nerve-mast cell contacts, epidermal thickness was increased after stress along with a tendency towards higher itch perception. We conclude that psychoemotional stress has differential NNCS effects in healthy and AD skin with pro-inflammatory effects in not yet affected skin and anti-inflammatory effects in inflamed skin. doi:10.1016/j.autneu.2013.05.142
Poster 20.18 Stress alters cytokine profile of the skin: prospective links to stress-induced NNCS regulation in skin Frank Risto Rommel, Badrinarayanan Raghavan, Susanne Tumala (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany), Uwe Gieler (Department of Dermatology, University Hospital Giessen, Giessen, Germany), Eva M.J. Peters (Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy, Justus-Liebig-University, Giessen, Germany) Organs at the self-environment interface are confronted with a plethora of exogenous and endogenous challenges. Adaptation to these challenges appears to be a distinct feature of the cholinergic system. The skin is known to possess an intrinsically acting stresscascade, in which acetylcholine may play a vital role in the regulation of peripheral inflammation and disease. Thus it is essential to address the role of stress perception and subsequent non-neuronal cholinergic system (NNCS) induced modulation of the skin in response to different kinds of stressors. By microarray analysis we compared skin