The effects of Ellagic acid supplementation on neurotrophic, inflammation, and oxidative stress factors, and indoleamine 2, 3-dioxygenase gene expression in multiple sclerosis patients with mild to moderate depressive symptoms: A randomized, triple-blind, placebo-controlled trial

Abstract

Background: Depression is one of the most common psychological disorders among multiple sclerosis (MS) patients that characterized as the first symptoms. Ellagic acid is a natural polyphenol that may have neuroprotective properties through antioxidant, anti-inflammatory, and immunomodulatory effects.

Purpose: The aim of the present study was to investigate the effects of Ellagic acid on circulating levels of brain derived neurotrophic factor (BDNF), interferon-γ (IFN-ƴ), nitric oxide (NO), nuclear factor erythroid-2-related factor 2 (Nrf2), cortisol, serotonergic system, and indoleamine 2, 3-dioxygenase (IDO) gene expression in MS patients with mild to moderate depressive symptoms.

Study design: A randomized triple-blind clinical trial.

Methods: The eligible patients according to the inclusion criteria were randomly divided into two groups: either 180 mg Ellagic acid (Axenic company) (n = 25) or 180 mg maltodextrin (n = 25) group for 12 weeks. The Ellagic acid supplement were identical to placebo in shape, color and odor. Serum BDNF, NO, Nrf2, cortisol, serotonin, and IFN-ƴ were measured by ELISA kit in the baseline and end of the study. Also, demographic characteristics, anthropometric measurements, physical activity, food intake, Beck Depression Inventory-II (BDI-II) and expanding disability status scale (EDSS) questionnaires, as well as IDO gene expression were assessed. SPSS software version 24 was used for statistical analysis.

Results: Fifty patients were evaluated, and a significant decrease in BDI-II (p = 0.001), IFN-ƴ (p = 0.001), NO (p = 0.004), cortisol (p = 0.015), IDO gene expression (p = 0.001) and as well as increased the level of BDNF (p = 0.006) and serotonin (p = 0.019) was observed among those who received 90 mg Ellagic acid twice a day for 12 weeks versus control group. However, there were no significant differences between groups for Nrf2 levels (p>0.05) at the end of study.

Conclusion: The current study indicates that Ellagic acid intervention has a favorable effect on depression in MS patients. This is achieved by reducing BDI-II scores, as well as levels of NO, cortisol, IFN-ƴ, and IDO gene expression. Furthermore, we found a significant elevation in circulating levels of BDNF and serotonin.

Keywords: Depression; Ellagic acid; Multiple sclerosis; Randomized controlled clinical trial.