Advanced Spray-Dried Inhalable Microparticles/Nanoparticles of an Innovative Mitophagy Activator for Targeted Lung Delivery: Design, Comprehensive Characterization, Human Lung Cell Culture, and In Vitro Aerosol Dispersion Performance

Hasham Shafi; Andrea J Lora; Haley M Donow; Saurabh Aggarwal; Panfeng Fu; Ting Wang; Heidi M Mansour

doi:10.1021/acsptsci.4c00436

Advanced Spray-Dried Inhalable Microparticles/Nanoparticles of an Innovative Mitophagy Activator for Targeted Lung Delivery: Design, Comprehensive Characterization, Human Lung Cell Culture, and In Vitro Aerosol Dispersion Performance

ACS Pharmacol Transl Sci. 2024 Oct 15;7(11):3540-3558. doi: 10.1021/acsptsci.4c00436. eCollection 2024 Nov 8.

Authors

Hasham Shafi¹, Andrea J Lora¹, Haley M Donow¹, Saurabh Aggarwal², Panfeng Fu^{1

3}, Ting Wang^{1

2

3}, Heidi M Mansour^{1

2

3

4}

Affiliations

¹ Florida International University Center for Translational Science, Port St. Lucie, Florida 34987, United States.
² Dept. of Cellular and Molecular Medicine, FIU Herbert Wertheim College of Medicine, Miami, Florida 33199, United States.
³ Dept. of Environmental Health Sciences, FIU Robert Stempel College of Public Health & Social Work, Miami, Florida 33199, United States.
⁴ Dept. of Biomedical Engineering, FIU College of Engineering & Computing, Miami, Florida 33199, United States.

PMID: 39539257
PMCID: PMC11555509 (available on 2025-10-15)
DOI: 10.1021/acsptsci.4c00436

Abstract

Urolithin A (UA) has demonstrated the ability to stimulate mitophagy and enhance mitochondrial and cellular health in skeletal muscles in humans after oral administration. It is hypothesized that targeted delivery of UA as inhaled dry powders to the lungs will enhance mitochondrial health through mitochondrial biogenesis. This study aimed to engineer inhalable excipient-free powders of UA as dry powder inhalers (DPIs) for targeted pulmonary delivery. The particles were designed by particle engineering from dilute organic solutions of UA using the state-of-the-art spray drying technology in a closed mode. Comprehensive physicochemical characterization and advanced microscopy techniques were conducted to examine phase behavior, molecular properties, and particle properties, which are necessary for the rational design of advanced pulmonary inhalation aerosols. Molecular fingerprinting was conducted by using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and Raman spectroscopy. Chemical imaging and mapping were conducted using confocal Raman microscopy (CRM) and IR microscopy. The advanced spray-dried (SD) excipient-free powders were successfully produced at different spraying pump feed rates and exhibited favorable molecular and particle properties. The excipient-free SD powders exhibited outstanding in vitro aerosol dispersion performance with an FDI-approved human DPI device (Neohaler) and correlated with the spray drying pump rate. In vitro, cell viability of various human pulmonary cells from different lung regions demonstrated biocompatibility and safety at different doses of UA. The transepithelial electrical resistance (TEER) assay shows that UA maintains cell membrane integrity and barrier tightness, indicating its potential for safe and effective localized drug delivery without long-term adverse effects. These results demonstrated that UA has favorable physicochemical and in vitro properties for inhalation and can be successfully engineered into excipient-free inhalable microparticles/nanoparticles as DPIs.