Potential Effects of Melatonin on TRPA1 Channels in the Prevention and Treatment of Alzheimer's Disease

Ahmet Özşimşek; İshak Suat Övey

doi:10.29399/npa.28183

Potential Effects of Melatonin on TRPA1 Channels in the Prevention and Treatment of Alzheimer's Disease

Noro Psikiyatr Ars. 2022 Aug 17;59(3):188-192. doi: 10.29399/npa.28183. eCollection 2022.

Authors

Ahmet Özşimşek¹, İshak Suat Övey²

Affiliations

¹ Department of Neurology, Medical School of Alanya Alaaddin Keykubat University, Turkey.
² Department of Physiology, Medical School of Alanya Alaaddin Keykubat University, Turkey.

Abstract

Introduction: Alzheimer's disease (AD) is the most common cause of dementia and is defined as a progressive neurodegenerative disease. Main clinical features of AD are progressive impairment in learning and memory loss. Several studies have indicated that mitochondria play a critical role in the pathogenesis of AD. In this study, we investigated the effect of melatonin on mitochondria-dependent TRPA1 ion channels in neuroblastoma cells by creating an in vitro model of Alzheimer's disease.

Methods: Okadaic acid was applied to SH-SY5Y (human neuroblastoma cell line) cells to create an AD model. After cellular differentiation, the following 7 main groups were created: Group 1 (Control), Group 2 (Mel+AD), Group 3 (Mel+AD+AP18), Group 4 (AD), Group 5 (AD+AP18), Group 6 (AD+Mel), and Group 7 (AD+Mel+AP18), and Alzheimer's disease was determined in vitro by examining the effect of melatonin on calcium-dependent TRPA1 channels in neuroblastoma cells.

Results: The Ca²+concentration was greater in the melatonin+AD, AD and AD+melatonin groups than in the control (p<0.001). However, there was no statistically significant difference between Mel+AD+AP18, AD+Mel+AP18 and the control. We determined that Ca²+ levels were lower in the melatonin+AD and AD+melatonin groups than in the AD group (p<0.001 and p<0.05). Additionally, cytosolic Ca²+ concentrations were found to be lower in the melatonin+AD group than in the AD+melatonin group (p<0.05). In evaluating the apoptosis and oxidative stress levels, we found that the apoptosis and intracellular ROS values were higher in the melatonin+AD, AD and AD+melatonin groups than in the control (p<0.001). In this respect, the mitochondrial depolarization and caspase-3 and caspase-9 levels were higher in the melatonin+AD, AD and AD+melatonin groups than in the control group (p<0.001). Additionally, the mitochondrial depolarization, caspase-3 and caspase-9 values were higher in the AD group than in the melatonin+AD and AD+melatonin groups (p<0.001), while mitochondrial depolarization and caspase-3 levels were lower in the melatonin+AD group than in the AD+melatonin group (p<0.001). However, in the same groups, there was no statistically significant difference in caspase-9 results. Additionally, the caspase-9 values were lower in the melatonin+AD group, AD group and AD+melatonin groups than in the melatonin+AD+AP18, AD+AP18 and AD+melatonin+AP18 groups, respectively (p<0.001 and p<0.05).

Conclusion: Our results suggest that melatonin may be an effective option in the treatment and prophylaxis of Alzheimer's disease by reducing cytosolic Ca²+ concentration, apoptosis and intracellular ROS through TRPA1 channels.

Keywords: Alzheimer’s disease; TRPA1; apoptosis; melatonin; neuroblastoma cells.