Antioxidant Effects of Chalcones during the Inflammatory Response: An Overall Review

Reactive oxygen/nitrogen species (ROS/RNS) are produced physiologically by several mechanisms, especially during the inflammatory response. However, their overproduction can lead to the evolution of conditions known as oxidative/nitrosative stress, resulting in the establishment of chronic inflammatory diseases. Chalcones are considered as a class of flavonoids having the molecular pattern 1,3-diaryl-2-propen-1-one. In the last few years, the antioxidant property of chalcones has been extensively studied, mainly due to their ability to inhibit the production or scavenging ROS/RNS. The antioxidant activity of chalcones, focusing on the production of ROS/RNS during the inflammatory response, is demonstrated and discussed in the present review. This literature revision was based on the modulatory effects of chalcones against different enzymes, such as superoxide dismutase (SOD), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, catalase (CAT), myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS), and, in the scavenging of ROS/RNS. Whenever possible, the structure-activity relationship (SAR) was established. Through the analysis accomplished in this review, it can be observed that the presence of substituents, e.g. hydroxyl, methoxyl, prenyl, and halogen atoms in the chalcones scaffold, often occurs and can improve their modulatory activities, namely, in the production of ROS/RNS during the inflammatory response.