MGB axis	Microbiota–gut–brain axis
5-HT	Serotonin
GABA	Gamma-aminobutyric acid
DA	Dopamine
CNS	Central nervous system
HPA	Hypothalamic–pituitary–adrenal
SCFAs	Short-chain fatty acids
E1	Estrone
E2	17β-estradiol
E3	Estriol
PI3K	phosphatidylinositol 3-kinase
Akt	Protein kinase B
Bcl-2	anti-apoptotic protein
BDNF	Brain-derived neurotrophic factor
IL-1β	Interleukin-1β
IL-6	Interleukin-6
TNF-α	Tumor necrosis factor alpha
SERT	5-HT transporter
SSRIs	Selective serotonin reuptake inhibitors
NMDA	N-metil-D-aspartate
AMPA	α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid
LTP	Long-term potentiation
PSD-95	Postsynaptic density protein 95
MAPK	Mitogen-Activated Protein Kinase
ERK	Extracellular signal-regulated kinase
PMDD	Premenstrual dysphoric disorder
MDD	Major depressive disorder
NE	Norepinephrine
BBB	Blood–brain barrier
IFN-γ	Interferon gamma
LPS	Lipopolysaccharides
ZO-1	Tight junction proteins
SHBG	Sex hormone-binding globulin
ERα	Estrogen receptor alpha
ERβ	Estrogen Receptor Beta
GH2	Glycoside hydrolase 2
gmGUS	Intestinal microbial β-glucuronidase
OVX	Ovariectomy
MAO	Enzyme monoamine oxidase
KP	Kynurenine pathway
IDO	Enzyme indoleamine 2,3-dioxygenase
KYNA	Kynurenic acid
QUIN	Quinolinic acid
TPH2	Tryptophan hydroxylase-2
DRN	Dorsal raphe nucleus
GPCR	G-protein-coupled membrane receptors
NF-KB	Nuclear factor kappa-light-chain-enhancer of activated B cells
TRP	Tryptophan
3β-HSD	3β-hydroxysteroid dehydrogenase
3/17β-HSD	3/17β-hydroxysteroid dehydrogenase
CUMS	Chronic unpredictable mild stress
CRP	C-reactive protein
CUS	Chronic unpredictable stress
NO	Nitric oxide
MDA	Malondialdehyde
GSH	Glutathione
ACTH	Adrenocorticotropic hormone
CORT	Corticosterone
PCOS	Polycystic ovary syndrome
PMS	Premenstrual syndrome