PTGS2 and early-onset autosomal dominant Alzheimer disease: Studies have suggested several mechanisms for the antioxidant activity of fucosterol, including increased activities of free radical scavenging enzymes such as GPx, CAT and SOD [61], inhibition of ROS generation by suppressing iNOS (Inducible nitric oxide synthase) and COX-2 (cyclooxygenase-2) [66,67], and inhibitory activities against biomarkers (β-secretase, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)) of Alzheimer’s disease [68].