Anti-Cholinesterase and Anti-α-Amylase Activities and Neuroprotective Effects of Carvacrol and p-Cymene and Their Effects on Hydrogen Peroxide Induced Stress in SH-SY5Y Cells

: Several researchers have demonstrated the health and pharmacological properties of carvacrol and p-cymene, monoterpenes of aromatic plants. This study investigated these compounds' possible anti-cholinesterase, anti-α-amylase, and neuroprotective effects. We evaluated the anti-acetylcholinesterase and anti-α-amylase activities at different concentrations of the compounds. The maximum non-toxic dose of carvacrol and p-cymene against SH-SY5Y neuroblastoma cells was determined using an MTT assay. The neuroprotective effects of the compounds were evaluated on H2O2-induced stress in SH-SY5Y cells, studying the expression of caspase-3 using Western blotting assays. Carvacrol showed inhibitory activities against acetylcholinesterase (IC50 = 3.8 μg/mL) and butyrylcholinesterase (IC50 = 32.7 μg/mL). Instead, the anti-α-amylase activity of carvacrol resulted in an IC50 value of 171.2 μg/mL After a pre-treatment with the maximum non-toxic dose of carvacrol and p-cymene, the expression of caspase-3 was reduced compared to cells treated with H2O2 alone. Carvacrol and p-cymene showed in vitro anti-enzymatic properties, and may act as neuroprotective agents against oxidative stress. Further studies are necessary to elucidate their possible use as coadjutants in preventing and treating AD in diabetic patients