AD	Alzheimer’s disease
AHR	Aryl hydrocarbon receptor
ALS	Amyotrophic lateral sclerosis
APOB	Apolipoprotein B
APOE	Apolipoprotein E
APP	Amyloid precursor protein
Aβ	Amyloid-β
BBB	Blood–brain barrier
BDNF	Brain-derived neurotrophic factor
BMI	Body Mass Index
C9orf72	Chromosome 9 open reading frame 72
CIDP	Chronic inflammatory demyelinating polyneuropathy
CNS	Central nervous system
DHA	Docosahexaenoic acid
EAE	Experimental autoimmune encephalomyelitis
ENS	Enteric nervous system
EPA	Eicosapentaenoic acid
FA	Fatty acids
FGF21	fibroblast growth factor 21
FMT	Fecal microbial transplantation
FUS	Fused in sarcoma
GCS	Glucosylceramide synthase
GF	Germ-free
GLP-1	Glucagon-like peptide-1
GM	Gut Microbiota
HCAR2	Hydroxycarboxylic acid receptor 2
IEB	Intestinal epithelial barrier
IGF-1	Insulin-like growth factor-1
IL-1β	Interleukin-1β
IL-6	Interleukin-6
LDL-C	Low density lipoprotein-cholesterol
LPS	Lipopolysaccharide
LRRK2	Leucine-rich repeat kinase 2
MAFLD	Metabolic dysfunction-associated fatty liver disease
MeD	Mediterranean Diet
MS	Multiple sclerosis
MTHFD1	Methylenetetrahydrofolate dehydrogenase-1
NF-kB	Nuclear factor kappa-light-chain-enhancer of activated B cells
NLRP3	Nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 3
PARK7	Parkinson disease protein 7
PD	Parkinson’s disease
PGC1α	Peroxisome proliferator activated receptor gamma coactivator 1-α
RBD	Rapid eye movement sleep behaviour disorder
ROS	Reactive oxygen species
SCFA	Short-chain fatty acids
SLC2A9	Solute carrier family 2 member 9
SNCA	α-synuclein (gene)
SOD1	Superoxide dismutase 1
T2D	Type 2 diabetes
TARDBP	TAR DNA binding protein-43
TDP-43	Transactive response DNA-binding protein 43
Th	T helper cells
TLR	Toll-like receptor
TNF-α	Tumor necrosis factor-α
Treg	T regulatory cells
WT	Wild type
α-syn	α-synuclein (protein)
ω-3 PUFA	Omega-3 polyunsaturated fatty acids