Marta Llovera, Marisol Ruiz-Meana, Andrea Irazoki, Carlos Lana, Javier Inserte, Manuel Portero-Otin, Juan G. Valero, Aida Beà, Guillermo López-Lluch, Antonio Zorzano, Daniel Sanchis, Patricia Pérez-Galán, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Fundació La Marató de TV3, Diputació de Lleida, Generalitat de Catalunya, Instituto de Salud Carlos III, Centres de Recerca de Catalunya, Institut Català de la Salut, [Beà A, Lana C] Cell Signaling & Apoptosis Group, Institut de Recerca Biomedica de Lleida (IRBLleida), Universitat de Lleida, Spain. [Valero JG] Department of Hematology-Oncology, Institut d’Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain. Centro de Investigacion Biomédica en Red-Oncología (CIBERONC), Barcelona, Spain. [Irazoki A] Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Centro de Investigación Biomédica en Red Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Universitat de Barcelona, Spain. [López-Lluch G] Andalusian Center of Developmental Biology, Pablo de Olavide University, Sevilla, Spain. Centro de Investigación Biomédica en Red Enfermedades Raras (CIBERER), Sevilla, Spain. [Portero-Otín M] Department of Experimental Medicine, IRBLleida, University of Lleida, Lleida, Spain. [Inserte J, Ruiz-Meana M] Laboratori de Cardiologia Experimental, Vall d’Hebron Hospital Universitari, Barcelona, Spain. Vall d’Hebron Institut de Recerca (VHIR), Barcelona, Spain. Universitat Autònoma de Barcelona, Spain. Centro de Investigación Biomédica en Red-CV (CIBER-CV), Barcelona, Spain, and Vall d'Hebron Barcelona Hospital Campus
Cardiovascular diseases are the leading cause of death globally and more than four out of five cases are due to ischemic events. Cardiac fibroblasts (CF) contribute to normal heart development and function, and produce the post-ischemic scar. Here, we characterize the biochemical and functional aspects related to CF endurance to ischemia-like conditions. Expression data mining showed that cultured human CF (HCF) express more BCL2 than pulmonary and dermal fibroblasts. In addition, gene set enrichment analysis showed overrepresentation of genes involved in the response to hypoxia and oxidative stress, respiration and Janus kinase (JAK)/Signal transducer and Activator of Transcription (STAT) signaling pathways in HCF. BCL2 sustained survival and proliferation of cultured rat CF, which also had higher respiration capacity and reactive oxygen species (ROS) production than pulmonary and dermal fibroblasts. This was associated with higher expression of the electron transport chain (ETC) and antioxidant enzymes. CF had high phosphorylation of JAK2 and its effectors STAT3 and STAT5, and their inhibition reduced viability and respiration, impaired ROS control and reduced the expression of BCL2, ETC complexes and antioxidant enzymes. Together, our results identify molecular and biochemical mechanisms conferring survival advantage to experimental ischemia in CF and show their control by the JAK2/STAT signaling pathway. The presented data point to potential targets for the regulation of cardiac fibrosis and also open the possibility of a general mechanism by which somatic cells required to acutely respond to ischemia are constitutively adapted to survive it., This research was funded by Ministerio de Ciencia e Innovación (MICINN), Gobierno de España, grant numbers SAF2013-44942-R and PID2019-104509RB-I00 to DS; Fundació La Marató TV3, grant number 20153810 to D.S; A.B. holds a contract from Fundació La Marató TV3 and IRBLleida/Diputació de Lleida; Generalitat de Catalunya, (AGAUR) grant number 2017SGR996 to DS; PP-G Laboratory support was obtained through research grants from MICINN (SAF2017/88275R) and CIBERONC (CB16/12/00334); JI and MR-M Laboratory support was obtained from Instituto de Salud Carlos III (ISCIII-FIS) grant PI19-01196; AZ Laboratory support was obtained through research grants from MICINN (PID2019-106209RB-I00), and the Generalitat de Catalunya, (AGAUR) grant number 2017SGR1015. AZ is a recipient of an ICREA ‘Academia’ Award (Generalitat de Catalunya). We gratefully acknowledge institutional funding from the MINECO through the Centres of Excellence Severo Ochoa Award, and from the CERCA Programme of the Generalitat de Catalunya.