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 H 2 O 2 -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 (IC 50 = 32.7 µg/mL). Instead, the anti-α-amylase activity of carvacrol resulted in an IC 50 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 H 2 O 2 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.