1. A novel non-hypoxic and sex-biased mechanism of HIF-1¿ in human aortic valve interstitial cells: crosstalk between JAK-STAT and TLR pathways
- Author
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Parra Izquierdo, Iván, Castaños-Mollor, Irene, López, Javier, Gómez, Cristina, San Román, José Alberto, Sánchez Crespo, Mariano, García-Rodríguez, Carmen, Ministerio de Economía y Competitividad (España), Universidad de Valladolid, and Junta de Castilla y León
- Subjects
Valvular Heart Disease ,Basic sciences ,Cardiac Diseases - Abstract
Resumen del póster presentado en European Society of Cardiology meeting 2018, celebrado en Munich (Alemania) del 25 al 29 de agosto de 2018., [Introduction]: Immune cell infiltration is one of the earliest events in calcific aortic valve disease (CAVD). Recent data showed that infiltrated T lymphocytes secrete active interferon (IFN)γ, the effects of which in resident valve cells remain unknown. In addition, angiogenesis has been pointed out as a key player in CAVD since new vessels formation and hypoxiainducible factor (HIF)1α have been detected in calcified aortic valves. However, its underlying molecular mechanisms are still poorly understood. Purpose: To elucidate the role of IFNγ on inflammation, angiogenesis and calcification of human aortic valve interstitial cells (AVIC) isolated from male and female patients. Methods: AVIC were isolated from healthy valves by collagenase digestion and exposed to IFNγ and/or lipopolysaccharide (LPS). Western Blot and ELISA were used to analyze proinflammatory and proangiogenic molecules. The osteogenic marker bone morphogenetic protein (BMP)2 and the antiangiogenic factor chondromodulin1 (ChMI) were analyzed by RTqPCR. Immunofluorescence was used to evaluate HIF1α nuclear translocation. Alizarin red staining and calcium deposits quantitation were performed to evaluate in vitro calcification of AVIC in highphosphate conditions., [Results]: Data showed that IFNγ and LPS cooperated to promote nuclear factor (NF)κB activation, and to induce adhesion molecule expression and interleukin (IL)6 secretion. Moreover, IFNγ and LPS combination promoted the induction of HIF1α and the secretion of its target gene, vascular endothelial growth factor (VEGF)A. The effect exhibited sex differences and was blocked with a HIF1α inhibitor. Additionally, a decrease of ChMI expression was observed. AVIC morphology markedly changed upon longterm stimulation with IFNγ, exhibiting an osteogenic phenotype characterized by BMP2 induction. Strikingly, marked sex differences were found in BMP2 expression and IL6 secretion. Finally, IFNγ promoted AVIC calcification that was further potentiated by LPS, being male AVIC more prone to calcification. Remarkably, pretreatment with the JAK1/2 inhibitor ruxolitinib abrogated IFNγ effects., [Conclusions]: IFNγ promotes proinflammatory, proangiogenic and proosteogenic responses in AVIC, which are potentiated by LPS in a sexspecific manner. Also, IFNγ combined with LPS induces HIF1α by a hypoxiaindependent mechanism. Our results point to JAKSTAT pathways as potential therapeutic targets for CAVD., Grants SAF201344521R; BIO/VA36/15, GRS 1432/A/16, CSI035P17; PI14/00022 and CIBERCV; FundDomingo Martínez. Fellowships from UVa and CyL government.
- Published
- 2018