AA	anthranilic acid
Acetyl-CoA	acetyl coenzyme A
ACMS	2-amino-3-carboxymuconate semialdehyde
ACMSD	2-amino-3-carboxymuconate-6-semialdehyde decarboxylase
acyl-CoA	acyl coenzyme A
AD	Alzheimer’s disease
ADHD	attention-deficit hyperactive disorder
AHR	aryl hydrocarbon receptor
ALS	amyotrophic lateral sclerosis
AMPA	α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid
AMS	2-aminomuconic-6-semialdehyde
AMSD	2-aminomuconate semialdehyde dehydrogenase
Aβ	amyloid beta
ASD	autism spectrum disorder
ATP	adenosine triphosphate
BAC	bacterial artificial chromosome
BCG	Bacillus Calmette-Guérin
BD	bipolar disorder
BPA	bisphenol A
BSSG	beta-sitosterol beta-d-glucoside
CA	cinnabarinic acid
CMS	chronic mild stress
C9orf72	chromosome 9 open reading frame 72
Cys	cysteine
EAE	experimental autoimmune/allergic encephalomyelitis
ER	endoplasmic reticulum
ETC	electron transport chain
FA	Friedreich’s ataxia
FADH2	flavin adenine dinucleotide
FVB	Friend leukemia virus B
GABA	gamma-aminobutyric acid
GAD	generalized anxiety disorder
GTP	guanosine triphosphate
GPR35	G-protein-coupled receptor 35
H+	proton
HD	Huntington’s disease
5-HT	serotonin
i.c.v.	intracerebroventricular
IDO	indoleamine 2,3-dioxygenase
IDO1	indoleamine 2,3-dioxygenase isoform 1
IDO2	indoleamine 2,3-dioxygenase isoform 2
3-HAA	3-hydroxyanthranilic acid
3-HK	3-hydroxy-L-kynurenine
3-HAO	3-hydroxyanthranilate oxidase
HTT	huntingtin
5-HTT	5-HT transporter
iPSC	induced pluripotent stem cells
KAT	kynurenine aminotransferase
KFA	kynurenine formamidase
KI	knock-in
KMO	kynurenine 3-monooxygenase
KO	knockout
KYN	kynurenine
KYNA	Kynurenic acid
KYNU	kynureninase
MDD	major depressive disorder
MELAS	mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes
MPT	mitochondrial permeability transition
MS	multiple sclerosis
mtDNA	mitochondrial DNA
MTF	mitofusin
NaAD	nicotinic acid adenine dinucleotide
NADH	nicotinamide adenine dinucleotide
NaMN	nicotinic acid mononucleotide
nDNA	nuclear DNA
NDUFS2	NADH:Ubiquinone Oxidoreductase Core Subunit S2
NMDA	N-methyl-D-aspartic acid
NMS	non-motor symptoms
OCD	obsessive-compulsive disorder
OXPHOS	oxidative phosphorylation
parkin	Parkinson juvenile disease protein 2
Pi	inorganic phosphate
PINK1	phosphatase and tensin homolog (PTEN)-induced kinase1
PD	Parkinson’s diseases
PFC	prefrontal cortex
PIC	picolinic acid
PLP	pyridoxal 5’-phosphate
PMD	primary mitochondrial disease
PMM	primary mitochondrial myopathy
PTSD	post-traumatic stress disorder
QPRT	quinolinate phosphoribosyltransferase
QUIN	quinolinic acid
RCS	reactive chemical species
SCZ	schizophrenia
SNP	single-nucleotide polymorphism
SMD	secondary mitochondrial dysfunction
SOD1	superoxide dismutase 1
SSRI	selective serotonin reuptake inhibitor
succinyl-CoA	succinyl coenzyme A
SUD	substance use disorder
TDP-43	transactive response (TAR) DNA binding protein 43 kDa
TDO	tryptophan 2,3-dioxygenase
TPH	tryptophan hydroxylase
Trp	tryptophan
TST	tail suspension test
XA	xanthurenic acid