Grobs, Y. | bioRxiv Science

bioRxiv2024

Exploring Integrin α5β1 as a Potential Therapeutic Target for Pulmonary Arterial Hypertension: Insights from Comprehensive Multicenter Preclinical Studies

Pulmonary arterial hypertension (PAH) is characterized by obliterative vascular remodeling of the small pulmonary arteries (PA) and progressive increase in pulmonary vascular resistance (PVR) leading to right ventricular (RV) failure. Although several drugs are approved for the treatment of PAH, mortality remains high. Accumulating evidence supports a pathological function of integrins in vessel remodeling, which are gaining renewed interest as drug targets. However, their role in PAH remains largely unexplored. We found that the arginine-glycine-aspartate (RGD)-binding integrin 5{beta}1 is upregulated in PA endothelial cells (PAEC) and PA smooth muscle cells (PASMC) from PAH patients and remodeled PAs from animal models. Blockade of the integrin 5{beta}1 or depletion of the 5 subunit resulted in mitotic defects and inhibition of the pro-proliferative and apoptosis-resistant phenotype of PAH cells. Using a novel small molecule integrin inhibitor and neutralizing antibodies, we demonstrated that 5{beta}1 integrin blockade attenuates pulmonary vascular remodeling and improves hemodynamics and RV function in multiple preclinical models. Our results provide converging evidence to consider 5{beta}1 integrin inhibition as a promising therapy for pulmonary hypertension. One sentence summaryThe 5{beta}1 integrin plays a crucial role in pulmonary vascular remodeling.

pathology↗

bioRxiv2024

ATP Citrate Lyase Drives Vascular Remodeling Diseases Development Through Metabolic-Epigenetic Reprograming.

Our study explores the previously uncharted role of ATP-citrate lyase (ACLY) in vascular remodeling within the pulmonary and coronary arteries, providing novel insights into the pathogenesis of pulmonary hypertension and coronary artery diseases. ACLY, involved in de novo lipid synthesis and histone acetylation, has emerged as a key regulator in sustaining vascular smooth muscle cell (VSMC) proliferation and survival. Utilizing human coronary and pulmonary artery tissues, our findings reveal an upregulation of ACLY expression during vascular remodeling processes. Inhibition of ACLY, achieved through pharmacological and molecular interventions in humans primary cultured VSMCs, leads to decreased proliferation, migration, and resistance to apoptosis. Mechanistically, these effects are associated with diminished glycolysis, lipid synthesis, GCN5-dependent histone acetylation, and FOXM1 activation. In vivo experiments, combining pharmacological and VSMC-specific ACLY knockout mice, ACLY inhibition demonstrates its efficacy in mitigating coronary artery remodeling and reducing pulmonary hypertension. Notably, initiating ACLY inhibition post-disease onset reverses pathological conditions, positioning ACLY as a promising therapeutic target. Human ex vivo tissue culture further supports our findings, showing reduced vascular remodeling in cultured human coronary artery rings and a reversal of pulmonary artery remodeling in precision-cut lung slices upon ACLY inhibition. This study introduces a groundbreaking concept, linking disparate abnormalities in vascular diseases to a common pathogenetic denominator, ACLY. The identified "multiple hit" therapeutic approach presents potential targets for addressing complex vascular diseases, offering avenues for future clinical interventions. ONE SENTENCE SUMMARYOur study delineates the pivotal role of ATP-citrate lyase in orchestrating vascular remodeling, establishing it as a compelling translational target for therapeutic interventions in pulmonary hypertension and coronary artery disease.

physiology↗