title: Inflammatory effects of TNFα are counteracted by X-ray irradiation and AChE inhibition in mouse micromass cultures.
abstract: As a means to analyze anti-inflammatory effects by radiation and/or by cholinergic mechanisms, we found that cultured primary human osteoblasts express most cholinergic components. After X-ray irradiation, their level of acetylcholinesterase (AChE) was strongly elevated. As a 3D model, we cultured mesenchymal stem cells isolated from E11 mouse embryos as micromass nodules, and differentiated them into chondro- and osteoblasts. They were stimulated by 5 or 10 ng/ml of the inflammatory cytokine TNF-α to mimic an inflammatory condition in vitro, before exposure to 2 Gy X-rays. Effects on chondro- and osteoblasts of TNF-α, of X-rays, or both were analysed by Alcian Blue, or Alizarin Red staining, respectively. Acetylcholinesterase (AChE) activity was visualized histochemically. The results showed that treatment with TNF-α affected cartilage and bone formation in vitro, while X-rays reversed the effects of TNF-α. After irradiation, both AChE and alkaline phosphatase (ALP) activities, a marker for bone mineralization, were raised, suggesting that X-rays stimulated cholinergic mechanisms during calcification. Notably, the TNFα-effects on cultures were also counterbalanced after AChE activity was blocked by BW284c51. These findings suggest a complex crosstalk between radiation, cholinergic and inflammatory mechanisms, which could have wide significances, e.g. for understanding rheumatoid arthritis.
authors.affiliation: Technische Universität Darmstadt, Developmental Biology & Neurogenetics, Schnittspahnstrasse 13, D-64287 Darmstadt, Germany.
authors.forename: Gopenath
authors.initials: G
authors.lastname: Thangaraj
authors.affiliation: Technische Universität Darmstadt, Developmental Biology & Neurogenetics, Schnittspahnstrasse 13, D-64287 Darmstadt, Germany.
authors.forename: Vadim
authors.initials: V
authors.lastname: Manakov
authors.affiliation: GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Planckstrasse 1, D-64291 Darmstadt-Wixhausen, Germany.
authors.forename: Aljona
authors.initials: A
authors.lastname: Cucu
authors.affiliation: GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Planckstrasse 1, D-64291 Darmstadt-Wixhausen, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fournier
authors.affiliation: Technische Universität Darmstadt, Developmental Biology & Neurogenetics, Schnittspahnstrasse 13, D-64287 Darmstadt, Germany. Electronic address: layer@bio.tu-darmstadt.de.
authors.forename: Paul G
authors.initials: PG
authors.lastname: Layer
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000528:radiation effects; D002478:Cells, Cultured; D002794:Choline / Q000378:metabolism; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D007249:Inflammation / Q000473:pathology*; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000528:radiation effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014965:X-Rays
chemical_list: D002800:Cholinesterase Inhibitors; D014409:Tumor Necrosis Factor-alpha; D000110:Acetylcholinesterase; D002794:Choline
keywords: Bone development; Cholinesterase inhibition; Inflammation; Mesenchymal stem cells; Micromass culture; X-rays irradiation