19.2 Microbiome and health Flashcards
When do we aquire the gut microbiome?
passage through birth canal
early stages of breastfeeding
What are the 5 main functions of the microbiome?
host defence metabolism immune system development intestinal epithelial cell maintenance and cell renewal gut brain axis
How might the gut microbiome aid us in metabolism?
fermentation of carbs that we cant digest
improved lipid digestion
activation of pro-nutrients (polyphenolic compounds)
biotransformation of bile
What are the 3 main enterotypes observed?
more bacteriocides (generally good for us) more prevotella (generally bad for us) more ruminococcus
How might we alter our enterotype?
the gut microbiome may shift with an environmental trigger, such as going on holiday for a prolonged period of time
What 4 factors may be responsible for alterations to gut microbiome composition?
age (>60 number of bacteria decreases)
immunity (may be interpreted as a threat)
genetics
diet (probiotics, iron, antibiotics…)
What effect does antibiotics have on the microbiome?
it depletes it
Do probiotics work?
not really, the stomach and the bacteria protect us from them
Why might we have observed an increase in autoimmune diseases sicnce the 1950’s?
were we getting rid of the microbiome with our use of antibiotics?
Which group of people are more likely to have autoimmune diseases?
How can this be minimised?
those born by C-section, as they don’t have a great microbiome
sraight after birth you swab the mum’s microbiome and dowse the baby in it
What is dysbiosis? what is its’ significance?
imbalance in microbial equilibrium, and an alteration in the bacterial communities present
this is significant in a whole load of diseases, including cancer, IBD, and Autism
What effect does IBD have on the microbiome?
overall decrease in the richness, number, and diversity of bacteria
firmicutes and bacteriocides decrease, but actinobacteria and proteobacteria are increased
In the healthy gut, what is the flora dominated by and supplemented by?
Dominated: firmicutes and bacteriocides
supplemented: actinobacteria and proteobacteria
In a healthy person, what is the epithelial-bacterial relationship?
we produce anti-microbial peptides to distance the bacteria,which is regulated by the immune system, all is in balance
In an unhealthy person, how is the epithelial-bacterial relationship compromised?
what is the stimulus?
bacteria are able to invade the mucosa, but we don’t know what the trigger is
