title: CD14 as a Mediator of the Mineralocorticoid Receptor-Dependent Anti-apolipoprotein A-1 IgG Chronotropic Effect on Cardiomyocytes.
abstract: In vitro and animal studies point to autoantibodies against apolipoprotein A-1 (anti-apoA-1 IgG) as possible mediators of cardiovascular (CV) disease involving several mechanisms such as basal heart rate interference mediated by a mineralocorticoid receptor-dependent L-type calcium channel activation, and a direct pro-inflammatory effect through the engagement of the toll-like receptor (TLR) 2/CD14 complex. Nevertheless, the possible implication of these receptors in the pro-arrhythmogenic effect of anti-apoA-1 antibodies remains elusive. We aimed at determining whether CD14 and TLRs could mediate the anti-apoA-1 IgG chronotropic response in neonatal rat ventricular cardiomyocytes (NRVC). Blocking CD14 suppressed anti-apoA-1 IgG binding to NRVC and the related positive chronotropic response. Anti-apoA-1 IgG alone induced the formation of a TLR2/TLR4/CD14 complex, followed by the phosphorylation of Src, whereas aldosterone alone promoted the phosphorylation of Akt by phosphatidylinositol 3-kinase (PI3K), without affecting the chronotropic response. In the presence of both aldosterone and anti-apoA-1 IgG, the localization of TLR2/TLR4/CD14 was increased in membrane lipid rafts, followed by PI3K and Src activation, leading to an L-type calcium channel-dependent positive chronotropic response. Pharmacological inhibition of the Src pathway led to the decrease of L-type calcium channel activity and abrogated the NRVC chronotropic response. Activation of CD14 seems to be a key regulator of the mineralocorticoid receptor-dependent anti-apoA-1 IgG positive chronotropic effect on NRVCs, involving relocation of the CD14/TLR2/TLR4 complex into lipid rafts followed by PI3K and Src-dependent L-type calcium channel activation.
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Tiphaine
authors.initials: T
authors.lastname: Mannic
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Satta
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Pagano
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Magaly
authors.initials: M
authors.lastname: Python
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Julien
authors.initials: J
authors.lastname: Virzi
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Montecucco
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Frias
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Richard W
authors.initials: RW
authors.lastname: James
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Andres D
authors.initials: AD
authors.lastname: Maturana
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Michel F
authors.initials: MF
authors.lastname: Rossier
authors.affiliation: Human Protein Sciences Department, Chemistry and Proteomic Group, Auto-immunity and Atherogenesis group; and Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine (T.M., N.S., J.V., F.M., N.V., M.F.R.), Geneva University Hospitals, 1201 Geneva, Switzerland; Department of Internal Medicine, Division of Endocrinology, Diabetology, Hypertension and Nutrition (M.P., M.A.F., R.W.J.), Geneva University Hospitals, Switzerland; Department of Bioengineering Sciences (A.D.M.), Graduate School of Bioagricultural Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601, Nagoya University, Japan; and Central Institute of the Hospital of Valais (M.F.R.), 1951 Sion, Switzerland.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Vuilleumier
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D016632:Apolipoprotein A-I / Q000276:immunology*; D001323:Autoantibodies / Q000494:pharmacology*; D020746:Calcium Channels, L-Type / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects*; D006352:Heart Ventricles / Q000166:cytology; D007074:Immunoglobulin G / Q000276:immunology*; D018950:Lipopolysaccharide Receptors / Q000187:drug effects* / Q000276:immunology; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000276:immunology; D010766:Phosphorylation; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018161:Receptors, Mineralocorticoid / Q000187:drug effects* / Q000276:immunology; D015398:Signal Transduction; D051195:Toll-Like Receptor 2 / Q000187:drug effects* / Q000276:immunology; D051197:Toll-Like Receptor 4 / Q000187:drug effects* / Q000276:immunology
chemical_list: D016632:Apolipoprotein A-I; D001323:Autoantibodies; D020746:Calcium Channels, L-Type; D007074:Immunoglobulin G; D018950:Lipopolysaccharide Receptors; D018161:Receptors, Mineralocorticoid; C495343:Tlr2 protein, rat; C495347:Tlr4 protein, rat; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D016392:Proto-Oncogene Proteins pp60(c-src)