Neuroprotective properties of Melissa officinalis after hypoxic-ischemic injury both in vitro and in vivo.
BACKGROUND
Brain ischemia initiates several metabolic events leading to neuronal death. These events mediate large amount of damage that arises after some neurodegenerative disorders as well as transient brain ischemia. Melissa officinalis is considered as a helpful herbal plant in the prevention of various neurological diseases like Alzheimer that is related with oxidative stress.


METHODS
We examined the effect of Melissa officinalis on hypoxia induced neuronal death in a cortical neuronal culture system as in vitro model and transient hippocampal ischemia as in vivo model. Transient hippocampal ischemia was induced in male rats by tow vessel-occlusion for 20 min. After reperfusion, the histopathological changes and the levels inflammation, oxidative stress status, and caspase-3 activity in hippocampus were measured.


RESULTS
Cytotoxicity assays showed a significant protection of a 10 μg/ml dose of Melissa against hypoxia in cultured neurons which was confirmed by a conventional staining (P<0.05). Melissa treatment decrease caspase3 activity (P<0.05) and TUNEL-positive cells significantly (P<0.01). Melissa oil has also inhibited malon dialdehyde level and attenuated decrease of Antioxidant Capacity in the hippocampus. Pro-inflammatory cytokines TNF-α, IL-1β and HIF-1α mRNA levels were highly increased after ischemia and treatment with Melissa significantly suppressed HIF-1α gene expression (P<0.05).


CONCLUSIONS
Results showed that Melissa officinalis could be considered as a protective agent in various neurological diseases associated with ischemic brain injury.
Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. hassanzadeh@tums.ac.ir.
Mohammad
M
Bayat
Abolfazl
A
Azami Tameh
Mohammad
M
Hossein Ghahremani
Mohammad
M
Akbari
Shahram Ejtemaei
SE
Mehr
Mahnaz
M
Khanavi
Gholamreza
G
Hassanzadeh