title: Plasma from pre-pubertal obese children impairs insulin stimulated Nitric Oxide (NO) bioavailability in endothelial cells: Role of ER stress.
abstract: Childhood obesity is commonly associated with early signs of endothelial dysfunction, characterized by impairment of insulin signaling and vascular Nitric Oxide (NO) availability. However, the underlying mechanisms remain to be established. Hence, we tested the hypothesis that endothelial insulin-stimulated NO production and availability was impaired and related to Endoplasmic Reticulum (ER) in human umbilical vein endothelial cells (HUVECs) cultured with plasma obtained from pre-pubertal obese (OB) children. OB children (N = 28, age: 8.8 ± 2.2; BMI z-score: 2.15 ± 0.39) showed impaired fasting glucose, insulin and HOMA-IR than normal weight children (CTRL; N = 28, age: 8.8 ± 1.7; BMI z-score: 0.17 ± 0.96). The in vitro experiments showed that OB-plasma significantly impaired endothelial insulin-stimulated NO production and bioavailability compared to CTRL-plasma. In parallel, in HUVECs OB-plasma increased GRP78 and activated PERK, eIF2α, IkBα and ATF6 (all ER stress markers). Moreover, OB-plasma increased NF-κB activation and its nuclear translocation. Notably, all these effects proved to be significantly restored by using PBA and TUDCA, known ER stress inhibitors. Our study demonstrate for the first time that plasma from obese children is able to induce in vitro endothelial insulin resistance, which is characterized by reduced insulin-stimulated NO production and bioavailability, endothelial ER stress and increased NF-κB activation.
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy. Electronic address: n.dipietro@unich.it.
authors.forename: Natalia
authors.initials: N
authors.lastname: Di Pietro
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: M Loredana
authors.initials: ML
authors.lastname: Marcovecchio
authors.affiliation: Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Di Silvestre
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: de Giorgis
authors.affiliation: Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Vincenzo Giuseppe Pio
authors.initials: VGP
authors.lastname: Cordone
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Lanuti
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Chiarelli
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Bologna
authors.affiliation: Department of Medicine and Aging Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Angelika
authors.initials: A
authors.lastname: Mohn
authors.affiliation: Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy; Centro Scienze dell'Invecchiamento e Medicina Traslazionale (CeSI-MeT), University "G. d'Annunzio", Chieti-Pescara, Italy; "G. d'Annunzio" University Foundation, Chieti, Italy.
authors.forename: Assunta
authors.initials: A
authors.lastname: Pandolfi
mesh_terms: D051702:Activating Transcription Factor 6 / Q000378:metabolism; D001682:Biological Availability; D015415:Biomarkers / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D002648:Child; D006152:Cyclic GMP / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects*; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D008954:Models, Biological; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D009765:Obesity / Q000097:blood*; D010766:Phosphorylation / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011627:Puberty / Q000097:blood*
chemical_list: C497111:ATF6 protein, human; D051702:Activating Transcription Factor 6; D015415:Biomarkers; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D007328:Insulin; D016328:NF-kappa B; D009569:Nitric Oxide; D052250:Nitric Oxide Synthase Type III; D051057:Proto-Oncogene Proteins c-akt; D006152:Cyclic GMP
keywords: ER stress; Endothelial dysfunction; Insulin resistance; Nitric oxide; Obesity