Pharmacology of gut microbiome Flashcards
what is the gut microbiome
the gut microbiome is the collective genome in the gut
give two possible reasons for reduced gut microbiota diversity
dietary fibre-deficient diet and antibiotic use
what is fecal microbial transplantation?
transfer o complex incompletely defined community of micro-organisms from a healthy donor (screened for the absence of pathogens) to a recipient.
the production of which metabolites can result from FMTT?
short-chain fatty acids and secondary bile acids
what clinical scenario is FMT currently used in?
clostridioides difficile colitis
what type of bacteria is c. diff?
an obligate anaerobic non-spore forming bacteria that produces a toxin.
what was the initial treatment of c. diff colitits?
antibiotic treatment; high failure rate.
what was the success rate of FMT from healthy donors to c. diff colitis patients?
90% success rate
what is acredited with FMT-related successful treatment of c. diff colitis?
the engraftment (establishment of replicating self-sustaining species) of donor symbiotic strains in the recipient
what is Rebyota?
FDA approved CDI treatment in patients aged 18+.
what were the most common symptoms associated with CDI?
abdominal pain, diarrhea, abdominal distension, flatulence and nausea
why was there more success with FMT in CDI than in UC?
In CDI, there is complete loss of microbiota, whereas in UC, would need bacteria already-present to adapt.
what obstacle has limited clinical use of FMT?
The inability to define donor samples’ exact composition
what are the five major phyla in gut?
bacteriodetes, firmicutes, verrucomicrobia, actinobacteria, and proteobacteria
plant-based diet increases the prevalence of which phylum in the gut?
plant based diet increases the prevalence of firmicutes in the gut
name two example species of firmicutes?
lactobacillales and clostridiales
give three functions of clostridiales?
resist pathogenic colonization, ameliorate IBD, and promote T cell differentiation
name two metabolites that clostridiales produce?
clostridiales produce butyrate and secondary bile acids.
how do lactobacillales impact the gut
lactobacillales interact with the gut epithelium to produce antimicrobial peptides, promote mucosal homeostasis and metabolise tryptophan to produce bioactive compounds
bacteriodetes comprise _ - _% of our colonic microbiota and this range is largely impacted by?
bacteriodetes comprise 5-60% of our colonic microbiota and this range is largely impacted by diet
which phyla can metabolise complex polysaccarides and how do they acheive this?
bacteriodetes can metabolise complex polysaccarides due to 25% of their genome encoding polysaccaride utilising loci
what is polysaccaride utilising loci
this loci is dedicated to polysaccaride import and degradation
what phylum is associated with enhanced response to immune checkpoint inhibitors?
verruccomicrobia
what is the predominant microbe in infant gut (ideally)?
bifidobacteria