Table 1.

Microbiota and its metabolites alterations in various psychiatric conditions.

The Disease	Microbiota-Related Fingerprint	Reference
Depression	↑ Bacteroidetes, Proteobacteria, Actinobacteria, Enterobacteriaceae, Alistipes, propionic, isobutyric, and isovaleric acids	[60,61,62,63]
	↓ Faecalibacterium, Bifidobacterium, Lactobacillus; serotonin, noradrenalin, SCFAs, kynurenic acid, kynurenine
Schizophrenia	↑ Corinobacteriaceae, Prevotella, Succinivibrio, Collinsella, Megasphaera, Klebsiella, Methanobrevibacter, Clostridium	[64,65]
	↓ Blautia, Coprococcus, Roseburia,
Bipolar disorder	↑ Bacteroides, Actinobacteria, Coriobacteria	[66,67]
	↓ Faecalibacterium, Roseburia, Alistipes,
Parkinson’s disease	↑ Bacteroides, Roseburia	[68]
	↓ Blautia, Coprococcus, Dorea, Oscillospira, Akkermansia
Autism Spectrum Disorder	↑ Streptococcus, Clostridiales, Comamonadaceae, Akkermansia, Rhosococcus, Oscillospira, Desulvibrio, Burkholderia, Collinsella, Corynebacterium, Dorea, and Lactobacillus; acetic and propionic acid, p-cresol, Glutamate,	[69,70,71,72,73]
	↓ Firmicutes, Faecalibacterium, Ruminococcus, Proteobacteria, Fuscobacteria, Verrumicrobia, Bifidobacterium, Neisseria, Alistipes, Bilophila, Dialister, Parabacteroides, and Veillonella, butyric acid, tryptophan, kynurenic acid,
Attention-Deficit Hyperactivity Disorder	↑ Actinobacteria (Bifidobacterium genus)	[74]
	↓ Firmicutes (Clostridiales order)
Alzheimer’s disease	↑ Blautia, Phascolarctobacterium, Gemella, E.coli, Shigella, Ps. aueruginosa	[75,76]
	↓ Ruminococcaceae, Turicibacteraceae, Peptostreptococcaceae, Clostridiaceae, Mogibacteriaceae, and the genera SMB53 (family, Clostridiaceae) Dialister, Clostridium, Turicibacter, and cc115 (family Erysipelotrichaceae)
Multiple sclerosis	↑ Akkermansia muciniphila, Acinetobacter calcoaceticus	[77]
	↓ Parabacteroides distasonis
Anorexia nervosa	↑ Methanobrevibacter smithii	[78]