Marilisa De Feudis1, Gillian Elisabeth Walker2, Giulia Genoni2, Marcello Manfredi3,4, Emanuela Agosti1, Mara Giordano2, Marina Caputo1, Luisa Di Trapani5, Emilio Marengo6, Gianluca Aimaretti1, Nicoletta Filigheddu1, Simonetta Bellone2, Gianni Bona2, Flavia Prodam2,3. 1. Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy. 2. Department of Health Sciences, University of Piemonte Orientale, Novara, Italy. 3. Interdisciplinary Research Center of Autoimmune and Allergic Diseases, University of Piemonte Orientale, Novara, Italy. 4. Innovative Solutions and Advanced LED Imaging Techniques s.r.l., Spin-off of Department of Sciences and Technological Innovation, University of Piemonte Orientale, Alessandria, Italy. 5. Clinical Biochemistry, Maggiore della Carità Hospital, Novara, Italy. 6. Department of Sciences and Technological Innovation, University of Piemonte Orientale, Alessandria, Italy.
Abstract
BACKGROUND: GH deficiency (GHD) is characterized by a cluster of cardiovascular risk factors and subtle inflammation. We aimed to demonstrate, through a proteomic approach, molecules directly modulated by GHD and involved in the inflammatory state. METHODS: Ten children with isolated GHD were studied before and after 1 year of treatment with rhGH and compared with 14 matched controls. A two-dimensional electrophoresis plasma proteomics analysis was performed at baseline and after GH treatment to identify the top molecules modulated by GH. In vitro studies on human hepatoma (HepG2) cells were performed to validate the data. RESULTS: Twelve of 20 proteomic spots were predicted to be isoforms α and β of haptoglobin (Hp) and confirmed by liquid chromatography tandem mass spectrometry and Western immunoblot analyses. Hp levels were higher in patients with GHD than controls at baseline (P < 0.001) and were reduced following GH treatment (P < 0.01). In HepG2 cells, both GH and IGF-1 were able to downregulate IL-6-induced Hp secretion. Moreover, Hp secretion was restored in pegvisomant-treated HepG2 cells. CONCLUSIONS: Hp is a molecule acting in the inflammatory state of GHD and a possible biomarker for GH treatment. Nevertheless, the contribution of other factors and the molecular pathways involved in the GH downregulation of Hp remain to be clearly defined.
BACKGROUND:GH deficiency (GHD) is characterized by a cluster of cardiovascular risk factors and subtle inflammation. We aimed to demonstrate, through a proteomic approach, molecules directly modulated by GHD and involved in the inflammatory state. METHODS: Ten children with isolated GHD were studied before and after 1 year of treatment with rhGH and compared with 14 matched controls. A two-dimensional electrophoresis plasma proteomics analysis was performed at baseline and after GH treatment to identify the top molecules modulated by GH. In vitro studies on humanhepatoma (HepG2) cells were performed to validate the data. RESULTS: Twelve of 20 proteomic spots were predicted to be isoforms α and β of haptoglobin (Hp) and confirmed by liquid chromatography tandem mass spectrometry and Western immunoblot analyses. Hp levels were higher in patients with GHD than controls at baseline (P < 0.001) and were reduced following GH treatment (P < 0.01). In HepG2 cells, both GH and IGF-1 were able to downregulate IL-6-induced Hp secretion. Moreover, Hp secretion was restored in pegvisomant-treated HepG2 cells. CONCLUSIONS: Hp is a molecule acting in the inflammatory state of GHD and a possible biomarker for GH treatment. Nevertheless, the contribution of other factors and the molecular pathways involved in the GH downregulation of Hp remain to be clearly defined.