Senolytics rejuvenate the reparative activity of human cardiomyocytes and endothelial cells

Introduction: Senescent cells have emerged as bona fide drivers of ageing and age-related cardiovascular disease, with senescent cells accumulating in the aged heart and following damage/injury. We have shown that the removal of senescent cells using senolytics(definition) can rejuvenate the regenerative capacity of the aged heart. Aim: To investigate the effects of cell senescence(definition) and the action of the senolytics, Dasatinib (D) and Quercetin (Q) on human iPSC-derived cardiomyocyte survival and cell cycle, and endothelial cell survival, cell cycle, migration and tube formation in vitro. Methods and Results: We developed a transwell insert co-culture stress-induced premature senescence human cell model system to test the effects of senolytics D+Q in vitro. Co-culture of iPSC-derived cardiomyocytes (iPSC-CMs) with senescent cardiac stromal progenitor cells (senCPCs) led to decreased number and DNA-synthesising activity of iPSC-CMs. Treatment with senolytics D+Q led to the elimination of senCPCs in the co-culture and the rescue of iPSC-CM number and DNA synthesis. Treatment of HUVECs with senCPC conditioned media decreased HUVEC number, cell cycle activity, migration, and tube formation. Treatment of HUVECs with D+Q conditioned media rescued HUVEC number, migration and tube formation. Next, we investigated the effects of co-culture of senescent HUVECs (senHUVECs) with HUVECs and showed decreased HUVEC number and DNA synthesis. Treatment with senolytics D+Q led to the elimination of senHUVECs in the co-culture and ameliorated HUVEC number, but not DNA synthesis. Treatment of HUVECs with conditioned media from senHUVECs led to decreased HUVEC migration and tube formation. Treatment of HUVECs with D+Q conditioned media improved HUVEC tube formation but not migration. Luminex analysis of the conditioned media from iPSC-CM and HUVEC co-cultures revealed upregulation of senescence-associated secretory phenotype (SASP) factors, but the level of SASP factors was reduced with the application of D+Q. Conclusion: Senescent cell removal by senolytics D+Q shows therapeutic potential in rejuvenating the reparative activity of human cardiomyocytes and endothelial cells. These results open the path to further studies on using senolytic therapy in age-related cardiac deterioration and rejuvenation. Potential impact of the findings: Senescent cells and their SASP present a promising therapeutic target to rejuvenate the heart’s reparative potential. Clinical trials using senolytics D+Q are already underway and thus far have shown promising results. Further pre-clinical studies are warranted for evidence-based clinical trials using senolytics in age-related cardiovascular diseases.