Effects of polyunsaturated fatty acids on interleukin-6 and brain-derived neurotrophic factor in monosodium glutamate-induced depression male rats

Abstract

Background: Depression is the most common psychiatric disorder affecting around 5% of the population worldwide. It leads to morbidity and affects quality of life. Monosodium glutamate (MSG) popularly called a tastemaker is used as a food additive in fast food and other processed foods. MSG has been implicated in causing depression. Since many adolescents and children are being habituated to fast foods, the current study is to evaluate the effects of polyunsaturated fatty acids (PUFAs) supplementation on plasma concentration of brain-derived neurotrophic factor (BDNF) and IL-6 which are important biochemical and immunological markers found in depression. Aims and Objectives: The aim of the current study was to assess the effect of supplementation of PUFA on MSG-induced depression in Wistar albino rats. Materials and Methods: The present prospective interventional study was conducted on 3-month-old, 24 male Wistar albino rats (weighing 200–300 g) for 21 days. The study group was divided into four equal groups among which 1st group that is control received distilled water with carboxymethylcellulose (CMC), the 2nd group positive control group received 500 mg of MSG along with CMC, the 3rd group normal control with PUFA received PUFA dissolved in CMC and the 4th group was positive control with PUFA received MSG dissolved in CMC and PUFA intervention was introduced from the 7th day. The study period was for 21 days and the 22nd day was an acclimatization day. The parameters in the blood samples of the rats were tested on the 23rd day using an ELISA kit and results were analyzed using Tukey’s post hoc test among the various groups and it was taken as statistically significant when the P < 0.05. Results: Among the groups, IL-6 levels raised and BDNF levels dropped in plasma of MSG-induced depressed rats. In PUFA-treated MSG-induced depressed rats, the plasma level of IL-6 was reduced and there was a significant rise in BDNF levels. Conclusion: PUFA supplementation is effective in treating MSG-induced depression in rats.