miR-199a Downregulation as a Driver of the NOX4/HIF-1α/VEGF-A Pathway in Thyroid and Orbital Adipose Tissues from Graves' Patients

• Published in: International journal of molecular sciences 2021-12, Vol.23 (1), p.153
• Main Authors: Craps, Julie, Joris, Virginie, Baldeschi, Lelio, Daumerie, Chantal, Camboni, Alessandra, Buemi, Antoine, Lengelé, Benoit, Behets, Catherine, Boschi, Antonella, Mourad, Michel, Many, Marie-Christine, Dessy, Chantal
• Format: Article
• Language: English
• Subjects: Adipocytes; Adipose tissue; Adipose Tissue - metabolism; Adult; Angiogenesis; Antioxidants; Biotin; Cancer; Disease; Down-Regulation - genetics; Fats; Female; Gene expression; Graves Disease - genetics; Graves Ophthalmopathy - genetics; Graves Ophthalmopathy - metabolism; Graves' disease; Graves’ orbitopathy; Humans; Hybridization; Hyperthyroidism; Hypoxia-Inducible Factor 1, alpha Subunit - genetics; Hypoxia-inducible factor 1a; Lipid peroxidation; Lipids; Male; Metabolic pathways; microRNA-199a; MicroRNAs - genetics; Middle Aged; NAD(P)H oxidase; NADPH Oxidase 4 - genetics; NOX4 protein; Oils & fats; Oxidative stress; Pathogenesis; Plasmas (physics); Protein expression; Proteins; Signal transduction; Signal Transduction - genetics; Stat3 protein; Thyrocytes; Thyroid; Thyroid gland; Thyroid Gland - metabolism; Thyroiditis; Vascular endothelial growth factor; Vascular Endothelial Growth Factor A - genetics; VEGF-A; Western blotting
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms23010153

Graves' disease (GD) is an autoimmune thyroiditis often associated with Graves' orbitopathy (GO). GD thyroid and GO orbital fat share high oxidative stress (OS) and hypervascularization. We investigated the metabolic pathways leading to OS and angiogenesis, aiming to further decipher the link between local and systemic GD manifestations. Plasma and thyroid samples were obtained from patients operated on for multinodular goiters (controls) or GD. Orbital fats were from GO or control patients. The NADPH-oxidase-4 (NOX4)/HIF-1α/VEGF-A signaling pathway was investigated by Western blotting and immunostaining. miR-199a family expression was evaluated following quantitative real-time PCR and/or in situ hybridization. In GD thyroids and GO orbital fats, NOX4 was upregulated and correlated with HIF-1α stabilization and VEGF-A overexpression. The biotin assay identified NOX4, HIF-1α and VEGF-A as direct targets of miR-199a-5p in cultured thyrocytes. Interestingly, GD thyroids, GD plasmas and GO orbital fats showed a downregulation of miR-199a-3p/-5p. Our results also highlighted an activation of STAT-3 signaling in GD thyroids and GO orbital fats, a transcription factor known to negatively regulate miR-199a expression. We identified NOX4/HIF-1α/VEGF-A as critical actors in GD and GO. STAT-3-dependent regulation of miR-199a is proposed as a common driver leading to these events in GD thyroids and GO orbital fats.