title: mESC-based in vitro differentiation models to study vascular response and functionality following genotoxic insults.
abstract: Because of high exposure to systemic noxae, vascular endothelial cells (EC) have to ensure distinct damage defense and regenerative mechanisms to guarantee vascular health. For meaningful toxicological drug assessments employing embryonic stem cell (ESC)-based in vitro models, functional competence of differentiated progeny and detailed knowledge regarding damage defense mechanisms are essential. Here, mouse ESCs (mESC) were differentiated into functionally competent vascular cells (EC and smooth muscle cells [SMC]). mESC, EC, and SMC were comparatively analyzed regarding DNA repair and DNA damage response (DDR). Differentiation was accompanied by both congruent and unique alterations in repair and DDR characteristics. EC and SMC shared the downregulation of genes involved cell cycle regulation and repair of DNA double-strand breaks (DSBs) and mismatches, whereas genes associated with nucleotide excision repair (NER), apoptosis, and autophagy were upregulated when compared with mESC. Expression of genes involved in base excision repair (BER) was particularly low in SMC. IR-induced formation of DSBs, as detected by nuclear γH2AX foci formation, was most efficient in SMC, the repair of DSBs was fastest in EC. Together with substantial differences in IR-induced phosphorylation of p53, Chk1, and Kap1, the data demonstrate complex alterations in DDR capacity going along with the loss of pluripotency and gain of EC- and SMC-specific functions. Notably, IR exposure of early vascular progenitors did not impair differentiation into functionally competent EC and SMC. Summarizing, mESC-based vascular differentiation models are informative to study the impact of environmental stressors on differentiation and function of vascular cells.
authors.affiliation: *Institute of Toxicology, Heinrich-Heine-University Düsseldorf, Institute of Neuro- and Sensory Physiology, Heinrich-Heine-University Düsseldorf, Moorenstrasse 5 and Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Hennicke
authors.affiliation: *Institute of Toxicology, Heinrich-Heine-University Düsseldorf, Institute of Neuro- and Sensory Physiology, Heinrich-Heine-University Düsseldorf, Moorenstrasse 5 and Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Nieweg
authors.affiliation: *Institute of Toxicology, Heinrich-Heine-University Düsseldorf, Institute of Neuro- and Sensory Physiology, Heinrich-Heine-University Düsseldorf, Moorenstrasse 5 and Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Brockmann
authors.affiliation: *Institute of Toxicology, Heinrich-Heine-University Düsseldorf, Institute of Neuro- and Sensory Physiology, Heinrich-Heine-University Düsseldorf, Moorenstrasse 5 and Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Matthias U
authors.initials: MU
authors.lastname: Kassack
authors.affiliation: *Institute of Toxicology, Heinrich-Heine-University Düsseldorf, Institute of Neuro- and Sensory Physiology, Heinrich-Heine-University Düsseldorf, Moorenstrasse 5 and Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Kurt
authors.initials: K
authors.lastname: Gottmann
authors.affiliation: *Institute of Toxicology, Heinrich-Heine-University Düsseldorf, Institute of Neuro- and Sensory Physiology, Heinrich-Heine-University Düsseldorf, Moorenstrasse 5 and Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany fritz@uni-duesseldorf.de.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Fritz
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000528:radiation effects; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism; D001343:Autophagy / Q000235:genetics / Q000528:radiation effects; D015415:Biomarkers / Q000378:metabolism; D002453:Cell Cycle / Q000235:genetics / Q000528:radiation effects; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation / Q000528:radiation effects*; D002460:Cell Line; D053903:DNA Breaks, Double-Stranded; D004260:DNA Repair; D053595:Embryonic Stem Cells / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D066026:Endothelial Progenitor Cells / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D005786:Gene Expression Regulation; D006657:Histones / Q000378:metabolism; D051379:Mice; D009131:Muscle, Smooth, Vascular / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D018919:Neovascularization, Physiologic / Q000235:genetics / Q000528:radiation effects; D039904:Pluripotent Stem Cells / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors
chemical_list: D051017:Apoptosis Regulatory Proteins; D015415:Biomarkers; D018797:Cell Cycle Proteins; D006657:Histones; D012333:RNA, Messenger; C475961:gamma-H2AX protein, mouse
keywords: DNA damage response; DNA repair; differentiation; ionizing radiation; mouse embryonic stem cells; vascular cells