Gut Microbiome and Cognitive Functions in Metabolic Diseases

Abstract

In recent years, there has been an increase in the study of metabolic illnesses and the gut microbiota. According to certain research, the pathogenesis and development of various metabolic illnesses, including type 1 and type 2 diabetes and obesity, may be significantly influenced by bacterial microbiome dysbiosis, and additionally, it has affected brain functions through metabolism. Recently, human research has discovered specific microbiota that are favorable and unfavorable to brain function. For instance, the Firmicutes phylum, which includes Clostridium, Ruminococcus, and Eubacterium, was beneficial to cognition, whereas the Bacteroidetes and Proteobacteria were detrimental. These results might encourage more investigation into the connections between the gut and cognition and mental health as well as to study the mechanisms of these relationships. With a focus on the gut microbiota and its relationships with physiological systems, the novel results that have so far been made show promise for identifying new therapeutic targets through food and nutrition.

Glossary

AAA:

Aromatic Amino Acids

AAC:

Anterior Cingulate Cortex

ADHD:

Attention-Deficit Hyperactivity Disorder

BBB:

Blood–Brain Barrier

BA:

Bile Acids

BMI:

Body Mass Index

CNS:

Central Nervous System

CRISPR:

Clustered Regularly Interspaced Short Palindromic Repeats

DA:

Dopamine

DLPFC:

Dorsomedial Prefrontal Cortex

DSM-V:

Diagnostic and Statistical Manual of Mental Disorders

dTMP:

deoxythymidine monophosphate

FTCD:

formimidoyltransferase cyclodeaminase

GABA:

Gamma-aminobutyric acid

GBA:

Gut–Brain Axis

GCS:

Glycine Cleavage System

GIT:

Gut intestinal tract

GLP-1:

Glucagon-like peptide-1

IEGs:

Immediate early genes

KEGG:

Kyoto Encyclopedia of Genes and Genomes pathway

LPS:

Lipopolysaccharides

MHO:

Metabolic health obesity

MRI:

Magnetic Resonance Image

NMDA receptor:

N-metil-d-aspartate receptor

OFC:

Orbitofrontal Cortex

PNS:

Peripheral Neurological System

PET:

Positron Emission Tomography

PFC:

Prefrontal cortex

T1DM:

Type 1 Diabetes Mellitus

T2DM:

Type 2 Diabetes Mellitus

THF:

Tetrahydrofolate

TYMS:

Thymidylate synthase

SAM:

S-adenosylmethionine

SCFAs:

Short-Chain Fatty Acids

ssDNA:

Single-stranded DNA

1C:

1 Carbon

Genes and Proteins

Microbial

ABC.VB1X. P:

putative thiamine transport system permease protein gene

aphA:

acid phosphatase/phosphotransferase

btuB:

cobalamin outer membrane transporter

folM:

dihydromonapterin reductase

folX:

dihydroneopterin triphosphate 2′-epimerase

fre:

NAD (P) H-flavin reductase

gcvH:

glycine cleavage system H

gcvP:

glycine decarboxylase

gcvR:

GCS transcriptional repressor

nudB:

dihydroneopterin triphosphate diphosphatase

opuD:

glycine betaine transporter OpuD

pabB:

aminodeoxychorismate synthase subunit 1

pabC:

aminodeoxychorismate lyase

pdxA:

4-hydroxythreonine-4-phosphate dehydrogenase

proV:

glycine betaine/l-proline ABC transporter ATP

proW:

betaine/proline transport system permease protein

proX:

betaine/proline transport system

purH:

bifunctional AICAR transformylase/IMP cyclohydrolase

purT:

phosphoribosylglycinamide formyl transferase 2

purU:

formyltetrahydrofolate deformylase

queE:

putative 7-carboxy-7-deazaguanine synthase

ribBA:

bifunctional 3,4-dihydroxy-2-butanone-4-phosphate synthase/GTP cyclohydrolase II

SadA:

staphylococcal aromatic amino acid decarboxylase enzyme

serA:

phosphoglycerate dehydrogenase

serB:

phosphoserine phosphatase

sox:

Sarcosine oxidase

ThiB:

Thiamine-binding periplasmic protein

thyX:

thymidylate synthase

ubiB:

ubiquinone biosynthesis protein UbiB

Human

TPH1:

tryptophan hydroxylase 1 gene

TYMS:

Thymidylate synthase gene

Mice

Arc:

Activity-regulated cytoskeleton-associated protein gene

Fos:

c-Fos protein gene

Egr2:

E3 SUMO-protein ligase EGR2 protein gene

Btg2:

Protein BTG2 protein gene

Ppp1r42:

protein phosphatase 1 regulatory subunit 42 gene

Sik1:

Serine/threonine-protein kinase SIK1

Dusp1:

Dual specificity protein phosphatase 1 gene

Ier2:

Immediate early response gene 2 protein gene