Omega-3 fatty acids prevent LPS-induced passive avoidance learning and memory and CaMKII-α gene expression impairments in hippocampus of rat.
BACKGROUND
Neuroinflammation is considered to be a major factor in several neurodegenerative diseases. Recently, the polyunsaturated fatty acid omega-3 has been shown to have anti-inflammatory effects and might play an effective role in improving memory impairment due to inflammation. In order to test this, we stimulated neuroinflammation in an animal model and induced memory dysfunction as measured by reduced retention of passive avoidance learning (PAL) and altered expression of CaMKII-α, a gene known to be crucial for memory formation. We then investigated whether treatment with dietary omega-3 prevents inflammation-induced memory dysfunction in this model.


METHODS
Male wistar rats (200-220 g) were fed either a control diet or a diet containing omega-3 (400mg/kg, po) for 1 month prior. Rats then received injection of either saline or LPS (500 μg/kg, ip) and were subjected to the PAL acquisition task. The retention test was performed 24h later, and animals were sacrificed immediately. Hippocampi were dissected and stored at -80°C. Finally, TNF-α levels and CaMKII-α gene expression were measured by ELISA and qRT-PCR, respectively.


RESULTS
We found that LPS treatment significantly impaired PAL and memory, increased TNF-α levels and impaired CaMKII-α gene expression. In control and LPS-injected animals, pre-treatment with omega-3 improved performance on the PAL task and increased CAMKII-α gene expression.


CONCLUSION
Taken together, these data suggest that dietary omega-3 may improve cognitive function and provide a potential therapy for memory impairment due to neuroinflammation.
['Dehkordi|Neda Gholamian|NG|', 'Noorbakhshnia|Maryam|M|', 'Ghaedi|Kamran|K|', 'Esmaeili|Abolghasem|A|', 'Dabaghi|Mohammad|M|']
D000818:Animals D001362:Avoidance Learning D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 D004032:Diet D015525:Fatty Acids, Omega-3 D015870:Gene Expression D006624:Hippocampus D008070:Lipopolysaccharides D008297:Male D008569:Memory Disorders D051381:Rats D014409:Tumor Necrosis Factor-alpha
Omega-3 Passive avoidance learning Memory CaMKII-α Hippocampus LPS