Assessment of anti-depressant activity of omega 3 fatty acids in rodents
Keywords:α-linolenic acid, Eicosapentaenoic acid, Forced swim test
Background: Depression contributes to significant disease burden at national and global levels. At the personal and domestic level too, depression leads to poor quality of life, causing a huge socioeconomic impact. In the world, over 300 million people are estimated to have depression and the numbers of depressed persons are only projected to go up.
Methods: The forced swim test (FST) is one of the most commonly used animal models for assessment of antidepressant effects in rodents. In the modified version of this test, the rats are forced to swim in a glass tank with no means of escape, inducing a behaviour of immobility, which resembles a state of despair, akin to depression in humans. The rats were divided into 6 groups: 1. control group: treated with distilled water; 2. standard group treated with fluoxetine Hcl (10mg/kg); 3.test-1 group treated with omega-3 FAs (300mg/kg); 4.test-2 group treated with a higher dose of omega-3 FAs (500 mg/kg); 5.test-3 group treated with omega-3 FAs (300mg/kg) and fluoxetine (10mg/kg); and 6.test-4 group treated with omega-3 FAs (500 mg/kg) and fluoxetine (10mg/kg).
Results: The independent between-groups ANOVA yielded a statistically highly significant result, F (5, 30) = 9.47, P <0.001. Thus, the null hypothesis of no difference between the means was rejected. To further evaluate the nature of the differences between the means of the six groups, the statically significant ANOVA result was followed by Tukey's honest significant difference post-hoc tests.
Conclusions: This study finds that omega 3 fatty acids have intrinsic antidepressant activity, and the combination of fluoxetine and omega 3 fatty acids has significantly more antidepressant effect than fluoxetine alone in the forced swim test done on Wistar rats.
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