Author/Authors :
Soodi، Maliheh نويسنده , , Dashti، Abolfazl نويسنده Department of Toxicology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran , , Hajimehdipoor، Homa نويسنده Traditional Medicine and Materia Medica Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. , , Akbari، Shole نويسنده Department of Toxicology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran , , Ataei، Nasim نويسنده Department of Toxicology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran ,
Abstract :
Objective: Extracellular deposition of the beta-amyloid (AB) peptide, which is the main finding
in the pathophysiology of Alzheimer’s disease (AD), leads to oxidative damage and apoptosis
in neurons. Melissa officinalis (M. officinalis) is a medicinal plant from the Lamiaceae
family that has neuroprotective activity. In the present study we have investigated the protective
effect of the acidic fraction of M. officinalis on AB-induced oxidative stress and apoptosis
in cultured cerebellar granule neurons (CGN). Additionally, we investigated a possible role of
the nicotinic receptor.
Materials and Methods: This study was an in vitro experimental study performed on
mice cultured CGNs. CGNs were pre-incubated with different concentrations of the acidic
fraction of M. officinalis for 24 hours, followed by incubation with AB for an additional 48
hours. CGNs were also pre-incubated with the acidic fraction of M. officinalis and mecamylamin,
followed by incubation with AB. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-
diphenyltetrazolium bromide (MTT) assay to measure cell viability. Acetylcholinesterase
(AChE) activity, reactive oxygen species (ROS) production, lipidperoxidation, and caspase-
3 activity were measured after incubation. Hochst/annexin V- fluorescein isothiocyanate
(FITC)/propidium iodide (PI) staining was performed to detect apoptotic cells.
Results: The acidic fraction could protect CGNs from AB-induced cytotoxicity. Mecamylamine
did not abolish the protective effect of the acidic fraction. AChE activity, ROS
production, lipid peroxidation, and caspase-3 activity increased after AB incubation. Preincubation
with the acidic fraction of M. officinalis ameliorated these factors and decreased
the number of apoptotic cells.
Conclusion: Our results indicated that the protective effect of the acidic fraction of M.
officinalis was not mediated through nicotinic receptors. This fraction could protect CGNs
through antioxidant and anti-apoptotic activities.
