A1	Pro-inflammatory reactive astrocyte phenotype
A2	Anti-inflammatory reactive astrocyte phenotype
Aβ	Amyloid-β
ACTH	Adrenocorticotropic Hormone
AD	Alzheimer’s Disease
ANS	Autonomic Nervous System
APP	Amyloid Precursor Protein
BBB	Blood–Brain Barrier
BDNF	Brain-Derived Neurotrophic Factor
cAMP	Cyclic Adenosine Monophosphate
CNS	Central Nervous System
COX-2	Cyclooxygenase-2
CRF	Corticotropin-Releasing Factor
CX3CL1	Chemokine (C-X3-C motif) ligand 1
CX3CR1	Chemokine (C-X3-C motif) receptor 1
DAMPs	Danger-Associated Molecular Patterns
ENS	Enteric Nervous System
FDA	Food and Drug Administration
FMT	Fecal Microbiota Transplantation
GABA	Gamma-Aminobutyric Acid
GDNF	Glial Cell Line-Derived Neurotrophic Factor
GPCR	G Protein-Coupled Receptor
HDAC	Histone Deacetylase
HPA	Hypothalamus-Pituitary-Adrenal (Axis)
IL	Interleukin
iNOS	Inducible Nitric Oxide Synthase
IP3	Inositol Triphosphate
LDH	Lactate Dehydrogenase
LPS	Lipopolysaccharide
MAPK	Mitogen-Activated Protein Kinase
MCFA	Medium-Chain Fatty Acid
MCI	Mild Cognitive Impairment
MCT	Monocarboxylate Transporter
MHC	Major Histocompatibility Complex
MIP	Macrophage Inflammatory Protein
MPTP	1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine
NaB	Sodium Butyrate
NF-κB	Nuclear Factor Kappa-light-chain-enhancer of Activated B cells
NGF	Nerve Growth Factor
NFT	Neurofibrillary Tangles
NO	Nitric Oxide
NOS	Nitric Oxide Synthase
NVU	Neurovascular Unit
PET	Positron Emission Tomography
PGC-1α	Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
PRRs	Pattern Recognition Receptors
PSEN1/2	Presenilin 1 and 2
ROS	Reactive Oxygen Species
RNS	Reactive Nitrogen Species
SCFA	Short-Chain Fatty Acid
TGF-β	Transforming Growth Factor Beta
TLR	Toll-Like Receptor
TNF-α	Tumor Necrosis Factor Alpha
ZO-1	Zonula Occludens-1