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Garcia de Alba Rivas, C.

Publications and source records attributed to Garcia de Alba Rivas, C..

2 recordsLinked to original sources

The oral drug nitazoxanide restricts SARS-CoV-2 infection and attenuates disease pathogenesis in Syrian hamsters

A well-tolerated and cost-effective oral drug that blocks SARS-CoV-2 growth and dissemination would be a major advance in the global effort to reduce COVID-19 morbidity and mortality. Here, we show that the oral FDA-approved drug nitazoxanide (NTZ) significantly inhibits SARS-CoV-2 viral replication and infection in different primate and human cell models including stem cell-derived human alveolar epithelial type 2 cells. Furthermore, NTZ synergizes with remdesivir, and it broadly inhibits growth of SARS-CoV-2 variants B.1.351 (beta), P.1 (gamma), and B.1617.2 (delta) and viral syncytia formation driven by their spike proteins. Strikingly, oral NTZ treatment of Syrian hamsters significantly inhibits SARS-CoV-2-driven weight loss, inflammation, and viral dissemination and syncytia formation in the lungs. These studies show that NTZ is a novel host-directed therapeutic that broadly inhibits SARS-CoV-2 dissemination and pathogenesis in human and hamster physiological models, which supports further testing and optimization of NTZ-based therapy for SARS-CoV-2 infection alone and in combination with antiviral drugs.

immunology↗

Chromatin alterations in the aging lung change progenitor cell activity

The lung contains multiple progenitor cell types that respond to damage, but how their responses are choreographed and why they decline with age is poorly understood. We report that histone H3 lysine 9 di-methylation (K9me2), mediated by histone methyltransferase G9a, regulates the dynamics of lung epithelial progenitor cells, and this regulation deteriorates with age. In aged mouse lungs, K9me2 loss coincided with lower frequency and activity of alveolar type 2 (AT2) cell progenitors. In contrast, K9me2 loss resulted in increased frequency and activity of multipotent progenitor cells with bronchiolar and alveolar potential (BASCs) and bronchiolar progenitors. K9me2 depletion in young mice through deletion or inhibition of G9a decreased AT2 progenitor activity and impaired alveolar injury regeneration. Conversely, K9me2 depletion increased chromatin accessibility of bronchiolar cell genes, increased BASC frequency and accelerated bronchiolar repair. K9me2 depletion also resulted in increased bronchiolar cell expression of the SARS-CoV2 receptor Ace2 in aged lungs. These data point to K9me2 and G9a as a critical regulator of the balance of lung progenitor cell regenerative responses and prevention of susceptibility to age-related lung diseases. These findings indicate that epigenetic regulation coordinates progenitor cell populations to expedite regeneration in the most efficient manner and disruption of this regulation presents significant challenges to lung health.

molecular biology↗