The observed decrease in nicotinamide may be related to its higher use in the nicotinamide phosphoribosyltransferase reaction that promotes pulmonary vascular remodeling in the development of pulmonary arterial hypertension (Chen et al., 2017), a common finding in chronic hypoxia (Ottolenghi et al., 2020; Gassmann et al., 2021). The gene discussed is NAMPT; the disease is pulmonary arterial hypertension.