WEEKS 8&9 Flashcards
Define the microbiome
The collective genome of the micro organisms in a particular environment
Define microbiota
The community of microorganisms themselves within a particular environment
What are commensal microbiota?
The relationship between microbes and their host which is mutually beneficial to both
What are probiotics?
Live microorganisms that are administered as supplements
What is alpha diversity and how is it achieved?
Alpha diversity is a richness and evenness of species in an environment for optimal health benefits
Achieved by eating a wide range of foods
How does microbiome of infants vary with birthing methods?
C section babies’ microbiome resembles that of the mothers skin
Natural babies’ microbiome resembles that of the mothers vagina
List factors which can influence composition of microbiome
- age
- drugs
- geography
- birthmode
- breastfeeding
- diet
- exercise
- disease
What are the 3 main mechanisms by which the microbiome effect host health?
- Protection of gut barrier integrity
- Triggering an innate immune response to structural component of bacteria leading to systemic inflammation
- Production of metabolites from dietary compounds through fermentation
What is dysbiosis
Dysbiosis is an ecosystem where bacteria no longer live in mutual harmony and pathogenic microbes as well as microbial metabolites enter through the epithelial layer, triggering an innate immune response
What is eubiosis
there are lots of good bacteria living harmoniously within the ecosystem and low levels of pathogenic species
What is the greatest substrate available for fermentation by the gut bacteria?
Resistant starch
What occurs when protein is fermented?
Production of TMAOs which are from the bacterial fermentation of choline and carnitine
Increases inflammation, collitis and linked to CVD
What are the effects of microbially produced imidazole proprionate?
Produced from histidine by type 2 diabetes associated bacteria
Impaired glucose tolerance by interfering with IRS pathway and GLUT4 recruitment
List 5 benefits of short chain fatty acids
- keeps pH of colon low to inhibit growth of pathogens
- low pH makes mineral easier to absorb (due to 2+ valence shell)
- stimulation of pancreatic secretions
- regulation of colonic epithelial proliferation (preventing colon cancer)
- modulation of appetite
What effect do artificial sweeteners have on the microbiome?
Decrease diversity and change the profile NOT in favour of glucose control
Makes you much more effective at extracting glucose from the diet