Neuroprotective effects of resveratrol through modulation of PI3K/Akt/GSK-3β pathway and metalloproteases

To analyze the expressional changes in the PI3K/Akt/GSK-3 beta pathway and metalloprotease in the cellular Alzheimer's Disease (AD) model with the effect of antioxidant resveratrol. Neuron-like cells were obtained by a two-step method of neuronal differentiation by using a combination of retinoic acid (RA) and brain-derived factor (BDNF) exposure. Then, the application of the amyloid beta peptide 25-35 (A beta 25-35) to the cell culture mimicked the environmental toxicity observed in AD. Afterward, cell viability and apoptosis assays were performed to determine whether the resveratrol exerts a cytotoxic and apoptotic effect. Finally, the expressional changes in genes in the cellular AD model with the effect of resveratrol were analyzed by Real-Time PCR. The analysis in silico was assessed using the STRING V12.0 database in each group. Apoptosis data findings were decreased by 1.5-fold and 2.5-fold respectively by Differentiated+Resveratrol (RES) and RES when compared to control but no significant difference was observed between RES and AD model groups. Real-time PCR analysis results revealed PI3K (3.38-fold), AKT (3.95-fold), and RELN (1.99-fold) expressions were significantly higher (p < .001), and also GSK-3 beta, TAU, ADAMTS-4, ADAMTS-5, and TIMP-3 gene expression levels were significantly downregulated (2.53-, 1.79-, 2.85-, 4.09-, and 6.62-fold, respectively) in the Differentiated+A beta + RES groups compared to the Differentiated+A beta group (p < .001). Network analysis shows the functional enrichment of 23 Alzheimer-related GO terms in the Wnt signaling, proteolysis, and extracellular matrix organization pathways. Resveratrol has inhibited GSK-3 beta by activating the PI3K/Akt insulin pathway in a neurotoxic environment. In addition, TAU, RELN, metalloproteases, and their inhibitors associated with Alzheimer's pathology have been regulated supporting the neuroprotective effect of resveratrol.