Ferroptosis is an iron-dependent and membrane lipid peroxidation-mediated form of programmed or regulated cell death. A number of recent studies have demonstrated that ferroptosis contributes to Alzhe Show more
Ferroptosis is an iron-dependent and membrane lipid peroxidation-mediated form of programmed or regulated cell death. A number of recent studies have demonstrated that ferroptosis contributes to Alzheimer's disease (AD)-mediated nerve cell death. Melatonin demonstrates strong antioxidant properties and offers protective benefits for the brain in the context of AD. However, it is not fully known whether melatonin protects against ferroptosis and whether ferroptosis affects amyloid precursor protein (APP) processing. In this study, we studied the effects of melatonin on SH-SY5Y cells-induced ferroptosis using erastin, and ferrostatin-1 was used as a ferroptosis inhibitor. To confirm the occurrence of ferroptosis, we conducted measurements of cell cytotoxicity, intracellular iron, reactive oxygen species (ROS), and 4-hydroxynonenal (4-HNE). The protein expressions that were regulated by either ferroptosis or APP processing were measured. Our results revealed that erastin increased intracellular iron levels, ROS, and 4-HNE lipid peroxidation in SH-SY5Y cells, resulting in an increased percentage of cell death. Erastin disrupted the regulation of proteins involved in ferroptosis and increased the production of amyloid beta (Aβ) through APP proteolysis. Following melatonin treatment, intracellular iron, ROS, and 4-HNE levels were significantly reduced. Additionally, the cystine/glutamate antiporter (system xc Show less
The beneficial actions of the natural compound Huperzine A (Hup A) against age-associated learning and memory deficits promote this compound as a nootropic agent. Alzheimer's disease (AD) pathophysiol Show more
The beneficial actions of the natural compound Huperzine A (Hup A) against age-associated learning and memory deficits promote this compound as a nootropic agent. Alzheimer's disease (AD) pathophysiology is characterized by the accumulation of amyloid beta (Aβ). Toxic Aβ oligomers account for the cognitive dysfunctions much before the pathological lesions are manifested in the brain. In the present study, we investigated the effects of Hup A on amyloid precursor protein (APP) proteolysis in SH-SY5Y neuroblastoma cells. Hup A downregulated the expression of β-site amyloid precursor protein cleaving enzyme 1 (BACE1) and presenilin 1 (PS1) levels but augmented the levels of A disintegrin and metalloproteinase 10 (ADAM10) with significant decrement in the Aβ levels. We herein report for the first time an in silico molecular docking analysis that revealed that Hup A binds to the functionally active site of BACE1. We further analyzed the effect of Hup A on glycogen synthase kinase-3 β (GSK3β) and phosphorylation status of tau. In this scenario, based on the current observations, we propose that Hup A is a potent regulator of APP processing and capable of modulating tau homeostasis under physiological conditions holding immense potential in preventing and treating AD like disorders. Show less