
Age-induced NLRP3 Inflammasome Over-activation Increases Lethality of SARS-CoV-2 Pneumonia in Elderly Patients
Author(s) -
Pedro C. Lara,
David Macías-Verde,
Javier Burgos-Burgos
Publication year - 2020
Publication title -
aging and disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.808
H-Index - 54
ISSN - 2152-5250
DOI - 10.14336/ad.2020.0601
Subject(s) - inflammasome , pyrin domain , pyroptosis , medicine , inflammation , immunology , apoptosis , biology , genetics
Age is one of the most important prognostic factors associated to lethality in SARS-CoV-2 infection. In multivariate analysis, advanced age was an independent risk factor for death. Recent studies suggest a role for the nucleotide-binding domain and leucine rich repeat containing family, pyrin domain containing 3 (NLRP3) inflammasome activation in lung inflammation and fibrosis in SARS-CoV and SARS-CoV-2 infections. Increased NLRP3/ apoptosis-associated speck-like protein (ASC) mRNA expression and increased caspase-1 activity, have been observed in aged lung, provoking increased and heightened expression levels of mature Interleukin (IL)-1β and IL-18 in aged individuals. Aged individuals have a basal predisposition to over-react to infection, displaying an increased hyper-inflammatory cascade, that seems not to be fully physiologically controlled. NLRP3 inflammasome is over-activated in aged individuals, through deficient mitochondrial functioning, increased mitochondrial Reactive Oxigen Species (mtROS) and/or mitochondrial (mt)DNA, leading to a hyper-response of classically activated macrophages and subsequent increases in IL-1 β. This NLRP3 over-activated status in elderly individuals, is also observed in telomere dysfunctional mice models. In our opinion, the NLRP3 inflammasome plays a central role in the increased lethality observed in elderly patients infected by COVID-19. Strategies blocking inflammasome would deserve to be studied.