DNA damage at the dawn of micro-RNA pathway impairment in pulmonary arterial hypertension

Over the last years, small non-coding microRNAs (miRNAs) have emerged as central actors of PAH etiology. Strong miRNA expression disorders occur in lungs as well as in right ventricle (RV) of PAH patients, which respectively lead to vascular remodeling of the distal pulmonary arteries and to RV failure. On the other hand, our understanding of PAH physiopathology has recently increased with the implication of DNA damage and DNA damage response (DDR) in this disease. Interestingly, DDR was described as a regulator of miRNA processing in both healthy and pathological conditions. In this review, we will first summarize miRNA expression impaired in lung and RV of PAH patients, then we will provide evidence that DDR could be at origin of miRNA pathway defects observed in pulmonary hypertension.