Possible association of Firmicutes in the gut microbiota of patients with major depressive disorder

Abstract

BackgroundGut microbiota can affect human behavior and mood in many ways. Several studies have shown that patients with depression were also accompanied with gut microbiota disorder, in which Firmicutes are related to the protective function of intestinal barrier. In this study, we explore the changes and effects of Firmicutes in the patients with major depressive disorder (MDD).MethodWe recruited 54 subjects, including 27 patients with MDD. Fecal samples were collected for identification by 16S rRNA sequencing and bioinformatics analysis.ResultsThe study shows that the alpha diversity indices of MDD patients are lower than those of the healthy controls. Firmicutes is the most significantly decreased phylum in the MDD samples. There are totally 13 taxonomic biomarkers with P-value <0.01 from Firmicutes. There are differences in 17 KEGG pathways between the two groups.ConclusionThis study found that there is a significant disorder of gut microbiota in the patients with depression, in which the Firmicutes decreased significantly. Defects of the Firmicutes may lead to the depression in short-chain fatty acids, which could account for the physiological basis of low-level inflammation of depression.LimitationsThis is a cross-sectional study and the sample size is comparatively small. Though several diet-related factors were controlled in the study, there is no quantified assessment of it.

Effect of Gut Microbiotas Diversity During 32-39 Weeks of Gestation on Postpartum Depression

“…In our study patients with PPD had a lower alpha diversity compared with the normal population. Similar to our results, Huang [13] reported that the alpha diversity indices of major depressive disorder were lower than healthy controls. In other studies [14,15], different results have been presented.…”

Addition of insoluble fiber to isolation media allows for increased metabolite diversity of lab-cultivable microbes derived from zebrafish gut samples

“…28 They have documented roles in fermentation of carbohydrates as well as lipid droplet formation for energy storage. 29,30 In our dendrogram we observe the same trend with a considerable number of our isolates grouped into the Firmicute phylum ( Figure 2 ). Of the Firmicutes isolated, B. subtilis was the most abundant isolate in this phylum.…”

Gut microbiome in Schizophrenia: Altered functional pathways related to immune modulation and atherosclerotic risk

“…It typically observed that low alpha-diversity is a hallmark of dysbiosis and represents "worse" health (Yatsunenko et al, 2012). However, the literature on alpha-diversity in psychiatric populations has been mixed (e.g., no differences Shen et al, 2018;Coello et al, 2019;Painold et al, 2019;Zheng et al, 2016;Naseribafrouei et al, 2014;Chen et al, 2018), decreased (Zheng et al, 2019;Huang et al, 2018;Ma et al, 2020), and increased (Zhu et al, 2020;Jiang et al, 2015). A recent meta-analysis of the gut microbiota in major depressive disorder revealed no difference in alpha-diversity between patients and NCs (Sanada et al, 2020).…”