Evaluation of Antioxidant and Protective Effects of Dracocephalum Moldavica Extract on Beta-Amyloid Peptide-Induced Toxicity in PC12 Cells

Excessive accumulation of beta-amyliod peptide, the major component of senile plaques in Alzheimer disease (AD), causes neuronal death through induction of oxidative stress. The medicinal plants from the Lamiaceae family contain the antioxidant activity. Moreover, neuroprotective properties of other species of this family have been reported.
Aerial parts of the plants were extracted with ethanol and water using maceration method. Antioxidant activity of the extract was evaluated by 2, 2-diphenyl-1-picrylhydrazyl radical scavenging. PC12 cells were incubated with different concentrations of the extract in culture medium 1h prior to incubation with amyloid beta peptide. Cell toxicity and biomarkers of oxidative stress were assessed 24h after addition of amyloid beta peptide by MTT assay.
Butylated hydroxytoluene )BHT( at concentrations of 0.01, 0.1, and 1 µg/ml had higher anti-radical activity than Dracocephalum moldavica extract. However, at higher concentrations, plant extract showed a higher anti-radical activity than BHT. The plant extract at the concentration range of 0.01-100 µg/ml did not show any toxic effect on PC12 cells. The plant extract at concentrations of 1, 10, and 100 µg/ml protected cells against beta amyloid toxicity and at concentration of 10 µg/ml was able to prevent biomarkers changes of oxidative stress induced by beta amyloid.
The extract of Dracocephalum moldavica prevents the toxicity of amyloid beta peptide by inhibiting the oxidative stress pathways and may useful in the treatment of AD.