Shear stress-exposed pulmonary artery endothelial cells fail to upregulate HSP70 in chronic thromboembolic pulmonary hypertension

Author(s):Show less -

Salibe-Filho, William ^[1] ; Araujo, Thais L. S. ^[2] ; Melo, Everton G. ^[2] ; Coimbra, Luiza B. C. T. ^[2] ; Lapa, Monica S. ^[1] ; Acencio, Milena M. P. ^[1] ; Freitas-Filho, Orival ^[3] ; Capelozzi, Vera Luiza ^[4] ; Teixeira, Lisete Ribeiro ^[1] ; Fernandes, Caio J. C. S. ^[1] ; Jatene, Fabio Biscegli ^[3] ; Laurindo, Francisco R. M. ^[5] ; Terra-Filho, Mario ^[1]

Affiliation

^[1] Univ Sao Paulo, Heart Inst InCor, Pulm Div, Hosp Clin, Fac Med, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Chem, Dept Biochem, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Cardiovasc Surg Div, Fac Med, Hosp Clin, Sao Paulo - Brazil

^[4] Univ Sao Paulo, Dept Pathol, Fac Med, Sao Paulo - Brazil

^[5] Univ Sao Paulo, Heart Inst InCor, Vasc Biol Lab, Hosp Clin, Fac Med, Sao Paulo - Brazil

• Document type: Journal article
• Source: PLoS One; v. 15, n. 12 DEC 3 2020.
• Web of Science Citations: 0

Abstract

The pathophysiological mechanisms underlying chronic thromboembolic pulmonary hypertension (CTEPH) are still unclear. Endothelial cell (EC) remodeling is believed to contribute to this pulmonary disease triggered by thrombus and hemodynamic forces disbalance. Recently, we showed that HSP70 levels decrease by proatherogenic shear stress. Molecular chaperones play a major role in proteostasis in neurological, cancer and inflammatory/ infectious diseases. To shed light on microvascular responses in CTEPH, we characterized the expression of molecular chaperones and annexin A2, a component of the fibrinolytic system. There is no animal model that reproduces microvascular changes in CTEPH, and this fact led us to isolated endothelial cells from patients with CTEPH undergoing pulmonary endarterectomy (PEA). We exposed CTEPH-EC and control human pulmonary endothelial cells (HPAEC) to high- (15 dynes/cm(2)) or low- (5 dynes/cm(2)) shear stress. After high-magnitude shear stress HPAEC upregulated heat shock protein 70kDa (HSP70) and the HSP ER paralogs 78 and 94kDa glucose-regulated protein (GRP78 and 94), whereas CTEPH-ECs failed to exhibit this response. At static conditions, both HSP70 and HSP90 families in CTEPH-EC are decreased. Importantly, immunohistochemistry analysis showed that HSP70 expression was downregulated in vivo, and annexin A2 was upregulated. Interestingly, wound healing and angiogenesis assays revealed that HSP70 inhibition with VER-155008 further impaired CTEPH-EC migratory responses. These results implicate HSP70 as a novel master regulator of endothelial dysfunction in type 4 PH. Overall, we first show that global failure of HSP upregulation is a hallmark of CTEPH pathogenesis and propose HSP70 as a potential biomarker of this condition. (AU)

• FAPESP's process: 20/11249-3 - The pathophysiology of endothelial cells isolated from patients with hypertensive pulmonary thromboembolism: mechanisms regulated by HSP70
• Grantee: Luiza Bitencourt de Carvalho Terci Coimbra
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 19/20435-8 - Molecular chaperone HSP70 mediates proteostasis in endothelial cells response to hemodynamic force
• Grantee: Thaís Larissa Araujo de Oliveira Silva
• Support Opportunities: Scholarships in Brazil - Young Researchers
• FAPESP's process: 15/06210-2 - GRASP pathway involving on the protein disulfide isomerase externalization and its implication in endothelial cell response
• Grantee: Thaís Larissa Araujo de Oliveira Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/13739-8 - Molecular chaperone HSP70 mediates proteostasis in endothelial cells response to hemodynamic force
• Grantee: Thaís Larissa Araujo de Oliveira Silva
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 13/07937-8 - Redoxome - Redox Processes in Biomedicine
• Grantee: Ohara Augusto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC