The Gut Microbiome Flashcards
Microbiota?
Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals.
Commensals?
A commensal is an organism that uses food supplied in the internal or the external environment of the host, without establishing a close association with the host, for instance by feeding on its tissues.
Commensal types?
- Commensalism:
Host provides environment. Bacteria ferment digested food. Present in latge numbers but harmless. - Mutualism:
Host provides environment. Bacteria metabolize host food to fatty acids and gases. Host uses fatty acids as energy - Parasitism:
Host provides environment. Protozoa feed on mucosa causing ulcers and dysentery
When is communsalism harmful?
May be harmful if tissues damaged(surgery), gut flora changes(antibiotics) or immunity reduced
Example of commensalism?
Large intestines of humans
&
Bacteroides spp.
Example of mutualism?
Bacteriodes spp.
&
Rumen of cattle
Example of parasitism?
Entamoeba histolytia
&
Large intestines of humans
What does the microbial community includes?
Bacteria
Protozoa
Fungi
Viruses
Archae(a type of prokaryote
Microbiota maturation depends on what?
- Mode of delivery:
Vaginal delivery
Cesarean delivery - Milk consumption
Solid food introduction - Medical Exposure
- Environment
Bacterial functions?
- Digestion of dietary components
- Maintenance of epithelial integrity
- Maintenance of epithelial function
- Maintenance of mucosal barrier
- Interaction with the host immune system
Microbiota metabolism?
Maintenance of epithelial structure & function?
Diseases associated with gut dysbiota?
Reversal of gut dysbiota?
- Prebiotics
- Probiotics
- Symbiotics
- Antibiotics
- Postbiotics
- Faecal transplantation
Caveat?
Ideally human randomised controlled trials to determine efficacy.
Two categories of microbiome-based therapy?
- Therapeutic
- Description
Therapeutic Based Therapy VS description
- Content
- Fecal microbiota
- Prebiotics vs non-digestible molecules to boost bacterial growth
- Fecal Microbiota transplantation VS feces from a healthy donor
Microbiota obesity and bile acids?
- Intestinal microbiota deconjugate and
dehydroxylate primary bile acids - Reabsorbed bile acids stimulate GLP-1
- GLP-1 has an incretin effect
4 .Glucose control stabilised
Ulcerative colitis?
What changes in microbiota causes?
- Intestinal porosity
- Immune response of the mucosa
- LPS release causes leaky gut
- LPS causes inflammation of liver and
adipose tissue - Impaired glucose control results
Faecal microbiota transplantation?
Reversal of ulcerative colitis?
Omics in GIT?
How does diet affect microbiota?
Calorie restriction causes reversible microbiota
Changes.
How does physical activity affect microbiota?
Physical activity changes gut microbiota
How does bariatic surgery affect microbiota?
Bariatric surgery changes gut microbiota
How are prebiotics transformed into in obesity?
Prebiotics fermented to short-chain fatty acids
How are probitoics & inflammation in obesity
Probiotics reduce inflammation and leptin
Effect of the dysregulation of gut?
Dysregulation of gut microbiota causes significant disease.
What is used in the regulation of the microbiota?
Reversal of microbiota dysregulation an increasingly used therapeutic application.
