Aquaporin Membrane Channels in Oxidative Stress, Cell Signaling, and Aging: Recent Advances and Research Trends

Abstract

Reactive oxygen species (ROS) are produced as a result of aerobic metabolism and as by-products through numerous physiological and biochemical processes. While ROS-dependent modifications are fundamental in transducing intracellular signals controlling pleiotropic functions, imbalanced ROS can cause oxidative damage, eventually leading to many chronic diseases. Moreover, increased ROS and reduced nitric oxide (NO) bioavailability are main key factors in dysfunctions underlying aging, frailty, hypertension, and atherosclerosis. Extensive investigation aims to elucidate the beneficial effects of ROS and NO, providing novel insights into the current medical treatment of oxidative stress-related diseases of high epidemiological impact. This review focuses on emerging topics encompassing the functional involvement of aquaporin channel proteins (AQPs) and membrane transport systems, also allowing permeation of NO and hydrogen peroxide, a major ROS, in oxidative stress physiology and pathophysiology. The most recent advances regarding the modulation exerted by food phytocompounds with antioxidant action on AQPs are also reviewed.

Figure 1

NO release by eNOS in physiological and peroxidative conditions. While “coupled” eNOS is involved in the physiological NO release underlying vasorelaxation, NO release by “uncoupled” eNOS is turned into OONO⁻ (peroxynitrites) leading to an increase in oxidative stress with consequent endothelial dysfunction. ADMA: asymmetric dimethylarginine; Akt: protein kinase B; BH4: tetrahydrobiopterin; CAM: calmodulin; Cav-1: caveolin 1; eNOS: endothelial NO synthase; cGMP: cyclic guanosine monophosphate; GTP: guanosine triphosphate; GTPCH: guanosine triphosphate cyclohydrolase I; Hsp 90: heat shock protein 90; NADPH: nicotinamide adenine dinucleotide phosphate; NO: nitric oxide; sGC: soluble guanylate cyclase; PKG: protein kinase G.