Reactive Oxygen Species and Inhibitors of Inflammatory Enzymes, NADPH Oxidase, and iNOS in Experimental Models of Parkinson’s Disease
Figure 7
Role of iNOS and NADPH oxidase and their inhibitors in oxidative stress and neuronal damage. Reactive oxygen species (ROS) can be generated in distinct ways, for example, cell activation by neurotoxins (MPTP, paraquat, and rotenone), and mitochondrial dysfunction and protein aggregation. ROSs have a role in oxidative stress, thereby causing neuronal injury or cell death which can be a factor for microglial activation. Several inhibitors of iNOS (L-N-iminoethyl-lysine (L-NIL), GW 274150, and aminoguanidine (AG)) and NADPH oxidase inhibitors diphenyliodonium (DPI), epigallocatechin (EGCG), and dextromethorphan (DM) as shown inhibit the generation of nitric oxide and superoxides, thereby inhibiting the formation of ROS and preventing neurodegeneration. Abbreviations: iNOS: inducible nitric oxide synthase, LPS: lipopolysaccharides, NADPH oxidase: nicotinamide adenine dinucleotide phosphate-oxidase, NO: nitric oxide, : peroxy radical, ONOO−: peroxynitrite, NF-κB: nuclear factor kappa, H2O2: hydrogen peroxide, TNF-α: tumor necrosis factor-alpha, PGE2: prostaglandin E2, IL-1β: interleukin-1 beta, and IFN-γ: interferon-gamma.
