title: Lymphocyte G-protein-coupled receptor kinase-2 is upregulated in patients with Alzheimer's disease.
abstract: Alterations in signal transduction pathway of G-protein-coupled receptors (GPCRs) have been found in the cerebrocortex and in the peripheral cultured tissues of patients with Alzheimer's disease (AD). The G-protein-coupled receptor kinase-2 (GRK2) plays an important role in regulating the GPCRs signaling: its increased expression is associated with receptor desensitization. The aim of this study was to explore GRK2 levels in peripheral lymphocytes of AD patients and to establish a correlation between lymphocyte protein concentrations and the degree of cognitive impairment. GRK2 mRNA and protein expression were evaluated in the lymphocytes of AD patients with mild or moderate/severe cognitive impairment and in age-matched healthy subjects. Both GRK2 mRNA and protein expression were higher in AD patients lymphocytes compared to controls. Furthermore, lymphocyte GRK2 levels were significantly correlated to the degree of cognitive decline. Our preliminary data suggest that GRK2 is involved in GPCRs coupling dysfunction observed in AD patients. Further studies are needed in order to verify whether the lymphocyte GRK2 might be utilized as a novel biomarker in AD diagnosis and clinical monitoring.
authors.affiliation: Dipartimento di Medicina Clinica, Scienze Cardiovascolari ed Immunologiche, Università Federico II, Via Pansini 5, Edificio 2, 80131 Naples, Italy. dleosco@unina.it
authors.forename: Dario
authors.initials: D
authors.lastname: Leosco
authors.forename: Francesca
authors.initials: F
authors.lastname: Fortunato
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rengo
authors.forename: Guido
authors.initials: G
authors.lastname: Iaccarino
authors.forename: Emma
authors.initials: E
authors.lastname: Sanzari
authors.forename: Luca
authors.initials: L
authors.lastname: Golino
authors.forename: Carmela
authors.initials: C
authors.lastname: Zincarelli
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Canonico
authors.forename: Massimo
authors.initials: M
authors.lastname: Marchese
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Koch
authors.forename: Franco
authors.initials: F
authors.lastname: Rengo
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis / Q000201:enzymology*; D015415:Biomarkers / Q000378:metabolism; D002469:Cell Separation; D003072:Cognition Disorders / Q000175:diagnosis / Q000201:enzymology / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D054769:G-Protein-Coupled Receptor Kinase 2; D006801:Humans; D008214:Lymphocytes / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D011237:Predictive Value of Tests; D012333:RNA, Messenger / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D015854:Up-Regulation / Q000235:genetics; D051552:beta-Adrenergic Receptor Kinases / Q000235:genetics / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled; C496567:GRK2 protein, human; D051552:beta-Adrenergic Receptor Kinases; D054769:G-Protein-Coupled Receptor Kinase 2