NOS2 and endothelial dysfunction: Interestingly, almost all of these mentioned mechanisms, involved in PH associated vascular remodeling and endothelial dysfunction, are linked to iron homeostasis, as iron exerts pivotal immunomodulatory effects, including the control of cytokine production and ROS/RNS generation by immune effector cells, the regulation of T cell polarization, and the functionality of the NO/NOS pathway as well as ET1 expression [8, 11, 34, 40, 41].