RT Journal Article T1 Celecoxib Microparticles for Inhalation in COVID-19-Related Acute Respiratory Distress Syndrome A1 Villa-Hermosilla, Monica-Carolina A1 Negro Álvarez, María Sofía Elisa A1 Barcia Hernández, Emilia María A1 Carolina Hurtado, A1 Consuelo Montejo, A1 Mario Alonso, A1 Fernández Carballido, Ana María AB Inhalation therapy is gaining increasing attention for the delivery of drugs destined to treat respiratory disorders associated with cytokine storms, such as COVID-19. The pathogenesis of COVID-19 includes an inflammatory storm with the release of cytokines from macrophages, which may be treated with anti-inflammatory drugs as celecoxib (CXB). For this, CXB-loaded PLGA microparticles (MPs) for inhaled therapy and that are able to be internalized by alveolar macrophages, were developed. MPs were prepared with 5% and 10% initial percentages of CXB (MP-C1 and MP-C2). For both systems, the mean particle size was around 5 µm, which was adequate for macrophage uptake, and the mean encapsulation efficiency was >89%. The in vitro release of CXB was prolonged for more than 40 and 70 days, respectively. The uptake of fluorescein-loaded PLGA MPs by the RAW 264.7 macrophage cell line was evidenced by flow cytometry, fluorescence microscopy and confocal microscopy. CXB-loaded PLGA MPs did not produce cytotoxicity at the concentrations assayed. The anti-inflammatory activity of CXB (encapsulated and in solution) was evaluated by determining the IL-1, IL-6 and TNF-α levels at 24 h and 72 h in RAW 264.7 macrophages, resulting in a higher degree of reduction in the expression of inflammatory mediators for CXB in solution. A potent degree of gene expression reduction was obtained with the developed CXB-loaded MPs. PB MPDI SN 1999-4923 YR 2022 FD 2022-06-30 LK https://hdl.handle.net/20.500.14352/92367 UL https://hdl.handle.net/20.500.14352/92367 LA eng NO Villa-Hermosilla, M.-C.; Negro, S.; Barcia, E.; Hurtado, C.; Montejo, C.; Alonso, M.; Fernandez-Carballido, A. Celecoxib Microparticles for Inhalation in COVID-19-Related Acute Respiratory Distress Syndrome. Pharmaceutics 2022, 14, 1392. https://doi.org/10.3390/pharmaceutics14071392 NO Universidad Complutense (UCM) research group, “Formulation and bioavailability of new drugs” DS Docta Complutense RD 8 abr 2025