‹› Disease ⇒ Depression ⇒ Major depressive disorder {40000197} Record Keys Type:Disease Parent:Depression Definition:Major depressive disorder Details Initialisation date:2020-12-03 Other Terms:MDD Meta Information MedDra ID:10012378 MedDra Level:pt ICD:[ ] Category:Psychiatry Zone:[ ] Mechanism:[ ] Notes: [ ]Shared Reference Notes [1.1] -The levels of fecal GABA and its relevant metabolites (N-acetylornithine, proline, oxoproline, and glutathione) were consistently decreased in MDD relative to HCs, suggesting a decrease in GABA content in the intestine. - A microbial enzyme–related gene (BetB) that participated in arginine metabolism to GABA was down-regulated in MDD. - Three microbial genes involved in the metabolism of glutamine to GABA was up-regulated in MDD. - Fecal GABA level in the patients with MDD may be modulated by a panel of gut microbes, which may be implicated in the development of MDD. - Majority of genes involved in the phenylalanine catabolic pathways were decreased in MDD, suggesting an inhibition of fecal phenylalanine degradation. - A downstream catabolic product of homovanillate was also decreased in MDD. These findings were consistent with disturbances of phenylalanine metabolism in MDD. - A gene (kynu) involved in kynurenic acid to quinolinic acid was enriched in MDD subjects relative to HCs, yielding an increased synthesis of the neurotoxic metabolite quinolinic acid. - A lower fecal quinolinic acid level in MDD. - These preliminary findings may account for the higher blood level of quinolinic acid observed in MDD. - Microbial GABA, phenylalanine, and quinolinic acid metabolisms were linked with MDD onset [1.2] - Major depression and anxiety states, are common in patients presenting with irritable bowel syndrome (IBS) [1.3] - Patients with major depressive disorder showed a statistically significant overrepresentation of #Bacteroides enterotype 2 compared to controls. [1.4] - γ-aminobutyric acid (#GABA) production by human-derived #Bacteroides is widespread, and there is a correlation between brain signatures of #Depression and fecal #Bacteroides levels in patients with major depressive disorder - γ-aminobutyric acid (#GABA) production by human-derived #Bacteroides is widespread, and there is a correlation between brain signatures of depression and fecal #Bacteroides levels in patients with major depressive disorder. [1.5] - MDD is associated with higher relative abundance of Clostridiales , OTU16802 Bacteroides and Prevotellaceae. - Similar association directions of for Blautia with MDD and SCZ. - Increased Bacilli is potentially associated with a higher risk of MDD, possibly involving dopamine metabolism which might play a role in the major symptoms of MDD. - Animal models found increased levels of Gammaproteobacteria were also associated with higher MDD risk and fluoxetine treatment was effective, implying strong correlations between gut microbiota and anxiety- and depression-like behaviors. (6) [1.6] - Mendelian randomization analysis indicated a potential causal effect of #Morganella on major depressive disorder, consistent with observational incident [1.7] - #Actinobacteria were found to be increased, whereas #Bacteroidetes were decreased in relation to other phyla, and some studies suggested decreased microbial diversity in MDD patients [1.8] - a 37-year-old female diagnosed with perioral dermatitis treated with minocycline, who within 1 week suffered from severe depersonalization symptoms. [1.9] [#Bipolar disorder, #Schizophrenia] - MDD was often characterized by higher #Alistipes and #Parabacteroides and lower #Prevotella; BD by higher #Bifidobacterium and #Oscillibacter; and SZ by higher #Prevotella and lower #Bacteroides, #Haemophilus, and #Streptococcus [#Bipolar disorder, #Schizophrenia] - Gut microbiota in BD, MDD and SZ > increase in #Eggerthella and #Lactobacillus, together with a decrease in #Coprococcus was common for the three conditions in comparison to controls. [#Bipolar disorder, #Schizophrenia] - MDD and SZ shared higher levels of #Escherichia/#Shigella and #Veillonella whereas increased #Megasphaera and lower #Roseburia are common for BD and SZ. [#Bipolar disorder, #Schizophrenia] [#Quinolinic acid, #kynurenine] - shift in the #Tryptophan metabolism from #Serotonin to the kyn pathway is associated with BD, MDD and SZ, but only in mood disorders (BD and MDD) there was a preferential metabolism of Kyn to the potentially neurotoxic QA. [#Bipolar disorder] [#Bifidobacterium infantis] - the abundance of #Fusobacteriaceae, #Escherichia blattae DSM 4481 and #Klebsiella oxytoca were significantly augmented, whereas the #Bifidobacterium longum subsp. infantis ATCC 15697 = JCM 1222 was significantly reduced in BD group compared with MDD group [#Bipolar disorder] - MDD and BD had more commonalities, including higher #Enterococcus, #Flavonifractor, and #Streptococcus, and lower #Faecalibacterium and #Ruminococcus. [#Bipolar disorder] - #Prevotella 2 and #Ruminococcaceae UCG-002 are more prevalent in patients with MDD than BD patients. [#Depression] [#Lipopolysaccharide] - elevated GIT permeability with an increased translocation of LPS from gram-negative bacteria plays a significant role in the pathophysiology of MDD [1.11] - in MDD > Changes observed in lipoproteins, were consistent with the differential composition of gut microbiota belonging to the order #Clostridiales and the phyla #Proteobacteria/Pseudomonadota and #Bacteroidetes/#Bacteroidota. - #Citrate was significantly decreased and #Pyruvate was significantly increased in individuals with MDD. [1.12] - an increased relative abundance of #Bacteroidetes and #Proteobacteria is reported in major depressive disorder (MDD) patients, with a concurrent reduction in the #Firmicutes phylum also described - #Sutterella and #Eggerthella appear to be consistently linked with disease manifestations, with the growth of the first being disfavored over the second in MDD patients [1.13] - abundance of #Enterobacteriaceae and #Alistipes was increased, and #Faecalibacterium abundance was decreased in patients with major depressive disorder [1.14] [#Depression] - #Blautia, #Bifidobacterium and #Coprococcus with higher relative abundance in the treatment effective group were related to the efficacy of SSRIs antidepressants. [1.15] [#Depression] - Microbial signals, pathological neurobiological changes, and depressive emotions can activate the HPA axis, increasing the synthesis and release of cortisol. - As a part of the brain-gut axis, excessive levels of cortisol promote gut pathology by modulating intestinal barrier function and inflammatory responses, resulting in a leaky gut [#Short Chain Fatty Acid] - SCFAs were reported to be depleted in patients with MDD,2,32 while their administration resulted in antidepressant effects by ameliorating #Depression-related intestinal permeability and hypothalamic–pituitary–adrenal (HPA) axis reactivity, in particular #Butyrate - Shifts in the composition of bacteriophages in MDD patients have been documented, particularly changes in #Caudovirales bacteriophages. - An increase in #Eggerthella and decrease in #Sutterella were also consistently demonstrated in patients with MDD. - the increasing abundances of #Morganella predicted to have a causal effect on MDD. - isolated #Mycobacterium neoaurum, which can degrade testosterone by expressing the 3β-Hydroxysteroid dehydrogenase enzyme, from the feces of male MDD patients, and found that administering this strain to rats via oral gavage, induced depressive-like behaviors. [1.16] [#Depression, #Schizophrenia] [#Candida albicans] [1.17] [#Gender] - Women with MDD display higher levels of #Actinobacteria compared to healthy women, whereas men with MDD exhibited lower levels of #Bacteroidetes.References Notes[ ]