Activating P2Y1receptors improves function in arteries with repressed autophagy

Abstract

Objective and hypothesisThe importance of endothelial cell (EC) autophagy to vascular homeostasis in the context of health and disease is evolving. Earlier we reported that intact EC autophagy is requisite to maintain shear‐stress‐induced nitric oxide (NO) generation via glycolysis‐dependent purinergic signaling to eNOS. Here we illustrate the translational and functional significance of these findings.Methods and ResultsFirst, we assessed translational relevance using older male humans and mice that exhibit blunted EC autophagy and impaired arterial function vs. adult controls. Active hyperemia evoked by rhythmic handgrip exercise elevated radial artery shear rate similarly from baseline in adult (23±1 y) and older (68±2 y) subjects for 60‐min. Compared to baseline, indexes of autophagy initiation, p‐eNOSS1177 activation, and NO generation, occurred in radial artery ECs obtained from adult but not older volunteers. Regarding mice, indexes of autophagy and p‐eNOSS1177 activation were robust in ECs from adult (7 ± 1 months) but not older (23 ± 1 months) animals that completed 60‐min treadmill‐running. Further, results concerning the extracellular acidification rate (ECAR; Seahorse Bioanalyzer) indicate glycolysis and glycolytic capacity were elevated in response to 20 dyn/cm2 laminar shear stress x 45‐min in primary arterial ECs obtained from adult but not older mice. We next questioned whether the inability to initiate EC autophagy, glycolysis, and p‐eNOSS1177 precipitates dysfunction in arteries from older vs. adult mice. Compromised intraluminal flow‐mediated vasodilation displayed by arteries from older vs. adult mice was recapitulated in vessels from adult mice by : (i) NO synthase inhibition; (ii) acute autophagy impairment using 3‐methyladenine (3‐MA); (iii) EC Atg3 depletion (Atg3EC‐/‐ mice); (iv) purinergic 2Y1‐receptor (P2Y1‐R) blockade; and (v) germline depletion of P2Y1‐Rs. Importantly, P2Y1‐R activation using 2‐methylthio‐ADP (2‐Me‐ADP) improved vasodilatory capacity in arteries from : (i) adult mice treated with 3‐MA; (ii) adult Atg3EC‐/‐ mice; and (iii) older animals with repressed EC autophagy.ConclusionsArterial dysfunction concurrent with pharmacological, genetic, and age‐associated EC autophagy disruption is improved by activating P2Y1‐Rs.