Roopchand lecture 2 Flashcards
What are phytochemical? What is the largest group?
Phytochemicals are nonnutrient plant based compounds that can benefit human health. The largest group is polyphenonls.
What are the different types of polyphenols?
Nonflavnoids-
- still beans
- ligans
- phenolic acids
Flavanoids
1. flavnon-3 ols- Types include catechin & epicatechin which are monomers of anthocyandins (Pac’s) found cocoa, grapes, and chocolate
- Isoflavones
- flavones
- anthocyanins
Polyphenol-
location
function
levels depend upon
-location: Different concentrations of polyphenols exist in different parts of the plant.
-function: protect the plant form pathogens, extreme -weather, Uv light, and act as antioxidants which protect cell division
-levels depend upon:
degree of environmental stress it is exposed to
type of plant species
stage in plant development
What is are the two metabolic pathways and what are the beginning and end reactants?
- Sikhimate pathway- phosphoenol pyruvate and erethros 4 pyruvate undergoes a series of reactions to convert to phenalanine.
- Phenolproponoid pathway- phenalanine is the starting reactant which undergoes a series of reactions to produce compounds that can undergo multiple other reactions producing different phytochemicals. Once it gets to a certain stage it undergoes various reactions through enzymatic metabolism of a CHS enzyme to produce a variety of polyphenols.
Why are polyphenols important?
- Associated with lower levels of chronic disease.
ex: diabetes, irrable bowl syndrome, gut dysbiosis, metabolic syndrome etc.
problems with the food dessert solution?
- People don’t have proper knowledge in how to prepare new food
- Engage in bad habits
- cannot afford fresh food
Epdiemolological study vs. clinical study on consumption of antho and proanthocyanidins
Epdiemoliological study-consumption of antho and proanthocyanidins are associated with less gain of fat, prevents weight gain.
Clincial study: dietary polyphenols can improve metabolic health but you need to consume a wide variety from wide from a wide variety of sources.
Epidmemoliogical vs. clinical
Epidmemoliogical:
Pros: large number of subjects over long time
Cons: questionares are biased to what you remember and want to do.
Way food is prepared, stored, type of food and how it is consumed is variable.
Clinical:
Pros:can control enviromental variables and compare to placebo. Actual experiement involving food can be done»can measure specific biomarkers and compounds in sample
Cons: small number of subjects over short period of time
How does type of gut microbiota impact type of polyphenols in the body?
People with different types of gut microbiota consume produce different types of metabolites based on the polyphenols that are metabolized which have different effects on the body.
What are proanthocyanidins:
These are polymers of catechin & epicatechin.
A type-single bonded carbons connecting monomers
B type- double bonded carbons connecting monomers
The effects of adding grape polyphenols to the WD diet
- reduced inflammation cytokines release
- reduced presence of LPS in the gut
- strengthened gut barrier
- decrease in ceramide concentrations
- decrease in FXR receptors which control downsteam genes that regulate glucose metabolism and interact with bile acid salt to do so»Less glycogen is converted into glucose?»> less bile acid
- Contribute to metabolic resiliance
Increase in Akkermania
- Associated with good metabolic health
- when made into probiotics and supplemented to people with obesity
- reduced insulin sensitivity
- reduced plamsa insulin levels
- reduced blood markers for inflammation
- reduced blood markers for liver dysfunction
What is dietary fiber? What do epidemiological studies show? How is dietary fiber grouped?
- Decreases CVD
- Decreases Cancer
- Decreases type 2 diabetes
How does the gut microbiota link fiber with host health?
prebiotics (dietary fiber) is broken by probiotics (gut bacteria which ferment it) to produce postbiotics (short chain fatty acids)
How do microbes ferment SCA
Microbial enzymes breakdown dietary fibers to monosaccaride simple sugars where they are then fermented into different short chain fatty acids through various different reaction pathways involving multiple different types pathways.
Where are the SCFA’s found and what do they do?
- found in the cecum and proximial colon
- can be absorbed by all diffrerent types of cells in the body
- can be converted into acetyl coa needed to provide energy for the cell by through the krebs cycle in cells
- it helps regulate the absorption of ions
- it helps regulate gut motility
- it helps lower colonic pH
- tightens the connections between proteins to produce a strong gut barrier
- regulates mucin gene expression
- stimulates goblet cells to produce mucus for protection of gut
- anitmicrobial/bacteriocidal effects
- regulate immune sys. and metabolism
How do SCFA’s regulate gene transcrpition
They repress the effects of the Histone deacetylase allowing histone acetylase to add acetyl groups to lysine residues of the histone proteins in chromatin allowing transcription to occur which is responsible for apotosis, inflammation, cellular growth, and energy metabolism.
What is the connection between SCFA and host metabolism?
Mice experiment
After you gave healthy woman propionate after 7 weeks
-Mice fed a diet of 5% butyrate as a supplement to a high fat diet.
-Increase in energy expenditure
decrease in body fat
-increase in insulin sensitivity
healthy woman
-increase in insulin secretion and lower fasting glucose
-increased amount postprandial GLP 1 receptor and PYY form EEC cells.
Us recommended intake vs. Actually Consumed:
20-30 for woman
30-40 for men
10-20 actually consumed
Lean mice vs. obese mice expressed of what more things
Lean mice-expressed greater amount of proprionate and butyrate
obese mice
-metabolized more amino acids and sugars
-greater response for stress and detoxifcation
EU diet vs. boulspan village burkish diet:
EU diet: Burkish village diet
-plant based protein -more animal based protein
-animal protein -no antibiotics
- sugars and starch -high firmichutes to bacterichutes
-off of antibiotics for 6 monthsincrease in short chain fatty acids and
-
Describe effects of
Butyrate
Propionate
Acetate
Butryrate- inhibit growth of cancer colon cells while stimulating the growth of colon cells
- Suppresses macrophage, and dendritic cell attack against commensal bacteria
- Stimulates the release of antiinflammotory cytokines and suppress the attack of T regulatory cells against commensal bacteria
- Stimulates naive T cells cells to activate into pathogen attacking cells when inflammation occurs
Propionate- enters liver through portal vein and creates lipids, proteins and glycogen
Acetate-defends against enterohemmoragic ecoli infection
What happens when fiber is low in supply?
Bacteria convert branched chain amino acids into branched chain fatty acids which cause insulin resistance.
Effect of low fiber diet on mice. How can it be restored?
-A low fiber diet on mice will cause the gut microbiota to decrease within themselves and future generations. To restore it you need to implant feces from another mouse which has a healthy gut microbiota in addition to a high MAC diet.
