Psycobiotics Flashcards
Brain modulates GI tract through
Motility, secretion, absorption, blood flow
GI tract stimulates the brain through
Stimulation of IR or small molecules
Components of gut-brain axis
CNS + ANS + ENS + IS + GI tract + Neuroendocrine system
GI symptoms is comorbidity + Gut dysbiosis (metagenomic sequencing)
Neurological Diseases
New axis definition
Microbiota-gut-brain (MGB) axis
Gut microbes Mechanism
Peripheral serotonin secretion by epi cells + Immune cells to produce cytokines or develop immune cells in brain + Metabolites such as butyrate
Metabolites to the brain can
Alter cells in BBB or develop intestinal and brain cells
Psychiatric conditions linked to gut alterations
AI disease (MS) + Neurodegenerative disorders (Parkinson’s and Alzheimer’s) + Injury (spinal cord) + Neuropsychiatric (depression and anxiety)
Disorders and gut dysbiosis stage
Correlation (no proof bacteria play role)
Microbiota —> CNS
Microbial derived molecules, neuroactive molecules, Neuronal signalling
Microbial Derived Molecules for the CNS
SCFAs. Tryptophan metabolites, MAMPs
Neuroactive Molecules for CNS
Neurotransmitters biosynthesis and regulation of signalling
Neuronal Signalling of CNS
Vagal nerve stimulation
SCFAs and CNS
Microglial maturation and function
Tryptophan metabolites
Keratonin and serotonin stimulate AHR to modulate immune stimulating genes
MAMPs CNS responds to
LPS and PGN
Microbiota —> Immune System
MDM + immune pathways
MDM to immune system
SCFAs and MAMPs (PSA and TLR/NLR ligands)
Immune pathway regulated
Th17, Treg, APC, antibody, phagocytosis
Immune system –> CNS
Tissue inflammation, injury, and repair + neurogenesis + Neuronal development and connectivity
Tissue inflammation, injury, and repair
Th1 (IFNY), Th2 (IL-4), Th17, Treg (IL-10)
Neurogenesis
Monocytes
Neuronal development and connectivity
IL-17 and IFNY
CNS –> IS and Microbiota
Neuroendocrine singaling
Neuroendocrine signaling
HPA axis –> microbiota composition, intestinal permeability/motility, Immune regulation
Prebiotic pathway
Stimulate gut microbiota and neurochemicals (also stimulated by gut microbiota) –> stimulate brain function
Probioitcs and the communication with the CNS
Probiotics –> NT producing microbes
HPA Axis
Release cortisol that activates immune cells and leaky gut
Communication of microbiota with NS via
Neuronal pathways + Immune system + Metabolites
Probiotics can regulate these two things to help with brain function
Gut dysbiosis + Reduced barrier integrity
Gut dysbiosis effects on NS
Inflammation, activate HPA axis, alter NT and metabolite levels that then signal the vagus nerve
Signal the vagus nerve
Metabolites, NTs, serotonin
Reduced barrier integrity on NS
Leaky gut and bacterial migration –> Inflammation –> Inflammatory cytokines disrupt BBB
Healthy microbiota and the NS
Produce NTs, serotonin, SCFA –> stimulate the vagus nerve and ICs (SCFAs) –> produce cytokines
Gut microbes to CNS
Gut microbes release metabolites or stimulate M cells and DCs —> interact with ENS —> interacts with the CNS
SCFAs into ENS
Stimulate GPCRs –> stimulate T-regs
LPS and EPS as metabolites interacting with the ENS
Stimulate TLRs
ENS communication with CNS
Stimulates GPCRs or TLRs to stimulate GDNFs
DCs and Microfold cells action with ENS
Translocate microbes from lumen to lamina propia
Microbes and receptors
Interact directly or through metabolites (TLRs and GPCRs)
GPCR
G-protein couples receptor
GPCRs in the ENS
Interact with SCFAs to regulate colonic Tregs
TRL stimulation of the CNS
Stimulates GDNF to increase glial cell and enteric neurons (?)
GDNF
Glial cell line derived neutrophilic factor