https://doi.org/10.1007/s00392-025-02625-4
1LMU Klinikum der Universität München Medizinische Klinik und Poliklinik I München, Deutschland; 2Institute of Lung Health and Immunity and and Comprehensive Pneumology Center Helmholtz Center Munich Munich, Deutschland; 3Fralin Biomedical Research Institute at Virginia Tech Carilion Virginia, USA
Current pharmacological treatments for pulmonary hypertension (PH) aim to restore and maintain a healthy circulation in the pulmonary capillary bed. However, the mortality of PH remains high, and therapies able not only to ameliorate the symptoms but also to reverse vascular remodeling are needed. Gene therapy has the potential to target disease etiology and holds evident promise. We recently identified microRNA-224 as a lung enriched microRNA, orchestrating the BMP pathway. In this study we aimed to develop and test a gene therapeutic approach for targeting microRNA-224 in pulmonary hypertension.
In a first approach we overexpressed microRNA-224 in PH diseased mice (Sugen/Hypoxia model) using an adeno-associated virus (AAV). MiR-224 exacerbated PH, reflected by increased RV hypertrophy. Then, we aimed to inhibit miR-224 by an AAV encoding for a stem-loop with 2 microRNA binding domains (AAV-TuD224). We intra-tracheally aerosolized AAV-TuD224 to PH diseased mice using the same model (Sugen /hypoxia). AAV-Ctrl-treated mice developed severe PAH (measured by increased Fulton index, RVSP, cardiomyocyte hypertrophy and pulmonary arterial medial thickness), whereas AAV-TuD-224 significantly protected mice from pulmonary vascular remodeling and cardiac hypertrophy at the tissue, cellular and molecular levels.
Next, we aim to translate the miR-224 gene- therapeutic approach in pre-clinical large animal models. To achieve this goal, we first tested existing and new viral vectors in the ex-vivo model of precision cut lung slices (PCLS). We infected porcine PCLS with different AAV-GFP vectors and identified AAV1 to be the most efficient vector for targeting the lung vasculature. Further experiments are ongoing to test AAV1-TuD224 in porcine PCLS and identify and test new gene therapeutic vectors able to efficient target the lung vasculature and treat PH.
Our data indicate that aerosolized gene therapy targeting miR-224 ameliorates PH and cor pulmonale. Gene therapeutic approaches may represent a new therapeutic option to target the roots of the disease.