Book of Abstracts - New Frontiers 2022

Abstracts of poster presentations

THE ROLE OF NECROSIS-LIKE CELL DEATH MODES IN ORGAN DAMAGE IN EXPERIMENTAL PULMONARY ARTERIAL HYPERTENSION

I. Jarabicová, C. Horváth, E. Veľasová, L. Bies Piváčková, J. Vetešková, J. Klimas, P. Křenek, A. Adameová

Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Slovakia

Cell loss due to both necroptosis and pyroptosis has been shown to underlie the pathogenesis of various diseases, however, the role of such cell death modalities as well as their potential linkage in pulmonary arterial hypertension (PAH) remains not well understood. Therefore, detailed molecular analysis of both necroptosis and pyroptosis in the lung and right ventricular (RV) tissue affected by PAH was performed. The circulating levels of receptor-interacting protein kinase 3 (RIP3), associated with both investigated cell death forms, were also examined. In male Wistar rats, PAH was induced by a single injection of monocrotaline (MCT) (60 mg/kg, s.c.). The animals were sacrificed after 28 days (MCT group) or prematurely due to signs of rapid disease progression as a group with terminal stage of PAH (ptMCT group). The development of PAH was confirmed by changes in vital functions, increase in cardiac hemodynamic stress markers and RV hypertrophy. Western Blotting analysis revealed elevated expression of pThr231/Ser232-RIP3 as well as pSer345-mixed linkage kinase domain-like protein (pSer345-MLKL) in the RVs of both PAH stages, indicating necroptosis execution. Contrary, in the diseased lungs, upregulated pThr231/Ser232-RIP3 did not proceed to necroptosis but was likely associated with the activation of NLR family pyrin domain containing 3 (NLRP3) inflammasome resulting in pyroptosis execution. PAH caused an increase in the circulating RIP3 levels which were more evident in the terminal stage and positively correlated with RV hypertrophy marker – Fulton index, but not with cardiac hemodynamic stress marker – N-terminal pro-B-type natriuretic peptide (NT-proBNP). Taken together, this is the first study indicating that different necrosis-like cell death modes associated with RIP3 might underlie organ damage in PAH and that the circulating RIP3 might serve as an additional diagnostic and prognostic marker of RV hypertrophic injury under conditions of PAH.

Keywords: necroptosis, pyroptosis, pulmonary arterial hypertension, receptor-interacting protein kinase 3

Funding:APVV-20-0242, APVV-19-0458, APVV-15-0685, VEGA 1/0203/19, VEGA 1/0016/20

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