Advanced oxidation protein products (AOPP)

Advanced oxidation protein products (AOPPs) are a heterogeneous group of dityrosine-containing, cross-linked protein derivatives that serve as biomarkers of oxidative stress and potent inflammatory mediators [1, 2]. They are primarily formed through the reaction of plasma proteins, particularly albumin, with chlorinated oxidants such as hypochlorous acid, which is generated by the enzyme myeloperoxidase (MPO) in activated neutrophils and monocytes [5, 12]. Originally identified in patients with chronic uremia, AOPPs are now recognized for their role in promoting systemic inflammation and oxidative damage across various pathologies, including chronic kidney disease, atherosclerosis, and multiple sclerosis [3, 10]. Mechanistically, AOPPs act as ligands for the Receptor for Advanced Glycation End-products (RAGE) and the scavenger receptor CD36, triggering the activation of NADPH oxidase and the NF-κB pathway [6, 7]. This interaction induces a pro-inflammatory 'oxidative burst' in phagocytes, further amplifying tissue damage and oxidative stress [8, 11]. Therapeutic interventions targeting AOPPs include the use of antioxidants like N-acetylcysteine to inhibit their formation and the development of agents to block their downstream receptor interactions [8, 12]. Reducing AOPP levels is considered a promising strategy to mitigate the progression of chronic inflammatory and metabolic diseases [10, 12].

Other names

Advanced oxidative protein productsOxidized albuminChlorinated proteinsDityrosine-containing cross-linked protein products

AOPPs are targeted through the reduction of their formation by scavenging chlorinated oxidants and inhibiting myeloperoxidase activity, as well as by blocking their downstream signaling through receptors such as RAGE and CD36 [5, 8, 12].