FF2 study guide

Bioavailability

The rate and extent to which the therapeutic moiety is absorbed and becomes available to the site of drug action.

Phytochemicals

Bioactive non-nutrient compounds in fruits, vegetables, grains, and other plants.

Glycoside

A molecule that is bonded to a sugar group.

Aglycone

The compound that is left after the glycosyl group on a glycoside is replaced by a hydrogen atom.

Glycone

The sugar group that was separated from the aglycone.

Causes of pathogenesis of many human diseases

Overproduction of oxidants (reactive oxygen species and reactive nitrogen species) in the human body is involved in the pathogenesis of many chronic diseases.

what types of compounds discussed have antioxidant activity

Polyphenols and carotenoids are the two main kinds of antioxidant phytochemicals, and they contribute the most to the antioxidant properties of foods/plants.

polyphenols actions to improve cardiovascular disease mechanisms

Antioxidant polyphenols could modify molecular events towards an improvement in endothelial function, and therefore play an important role in the prevention of CVD.

role of antioxidants in aging

Free radicals and oxidative stress have been considered as important factors in the biology of aging and in many age-associated degenerative diseases, since the antioxidant systems are under deterioration during aging.

major antioxidants in strawberries (2 of them)

Anthocyanins and ellagitannins are the major antioxidant compounds among the phytochemicals of strawberry.

Allicin and its role in cardioprotection

Allicin, an antioxidant organosulfur compound from garlic, was found to protect the cardiovascular system by inducing vasorelaxation and alleviating cardiac hypertrophy, angiogenesis, platelet aggregation, hyperlipidemia and hyperglycemia.

antioxidant defenses in individuals with obesity

Antioxidant defenses (endogenous antioxidant compounds and antioxidant enzymes) of the obese are lower compared with their normal weight counterparts.

walnuts to treat or prevent Alzheimer’s

Polyphenolic compounds of walnuts reduced the oxidant and inflammatory load on brain cells, improved interneuronal signaling, increased neurogenesis, as well as enhanced sequestration of insoluble toxic protein aggregates.

Structural components of simple phenolic acids

Hydroxybenzoic acids have carboxyl groups (-COOH) attached to the phenol ring. Hydroxycinnamic acids have 2-propenoic acid group attached to the ring.

Health benefits of polyphenols

antioxidant, free radical scavenging, anti-inflammatory, anti-cancer

Health benefits of flavonoids

anti-bacterial, anti-inflammatory, anti-cancer, anti-viral.

General structure of flavonoids

A flavan nucleus with 15 carbon atoms within the 3 rings. Structure is 2 benzene rings connected by pyran ring.

What part of flavonoid structure is most important for antioxidant capacity

The B ring structure, donates hydrogen and an electron to hydroxyl radicals which neutralizes them.

How phenolic compounds have antioxidant activity

Direct free radical scavenging activity of phenolic compounds. Chelation of pro-oxidant metal ions (indirect effects).

Metal chelation

Metal Chelation is a chemical reaction that bonds metal ions to another molecule or ion resulting in a ring-like structure called a chelate ring.

Polyphenols role in metal chelation

Flavonoids can chelate metal ions (iron, copper, etc.) and by doing this they can inhibit free radical generation and oxidation stress.

Most bioavailable polyphenol

Genistein glucoside (soy isoflavone) has the highest bioavailability (100% bioavailable in body).

Least bioavailable polyphenol

anthocyanins

Bioavailability of polyphenols

Bioavailability is defined as the fraction of a nutrient or non-nutrient that is available for the human body for physiological functions and/or storage.

Factors influencing the bioavailability of polyphenols

Release of polyphenols from food; Digestion of polyphenols; Cellular uptake of aglycons and some polyphenols by enterocytes (intestinal cells); Microbiological fermentation of non-absorbed polyphenols; Enzymatic modification; Transport in the bloodstream and tissue redistribution; Excretion via kidney.

Additional factors affecting bioavailability

External factors: sun exposure, degree of ripeness (when food is growing). Food processing: homogenization, lyophilization, cooking methods, storage. Food-related factors: amount of fat, fiber, etc. in the meal. Interaction with other compounds. Polyphenol related factors: chemical structure, concentration in food, amount introduced. Host related factors: intestinal factors, gender, age, genetics, etc.

What are general structural components of simple phenolic acids like hydroxybenzoic acid

and hydroxycinnamic acid

Structural components of simple phenolic acids Hydroxybenzoic acids have carboxyl groups (-COOH) attached to the phenol ring. Hydroxycinnamic acids have a 2-propenoic acid group attached to the phenol ring.

Names of simple phenolic acids

Gallic Acid, Protocatechuic acid, P-hydroxybenzoic acid, Syringic Acid, Ferulic Acid, Caffeic acid, P-Coumaric acid, Sinapic Acid.

Examples of functions of simple phenolic acids

Reduced LDL cholesterol, total cholesterol, triglycerides, increased HDL cholesterol. Reduced oxidative stress and inflammatory biomarkers.

Function of stilbenes in plants

Made by plants to help them defend themselves against pathogens, bacterial and fungal growth and damaging effects of UV light.

Stilbene consumption levels

quantity is low in the human diet, any effect of this molecule is unlikely at normal nutritional intake.

Resveratrol slide

How much it would take to consume 1 gram of resveratrol through food products alone: Therefore, supplements are needed to achieve higher doses.

Food sources of lignans

seeds, grains, fruits and vegetables, and in higher concentrations in sesame and flax seeds.

Examples of lignan food sources

Flaxseeds, cashews, peanuts, broccoli, Brussel sprouts, green beans, apricot, pears, wine, tea, soymilk, fruit juices, coffee.

Potential health benefits of lignans

Anti-microbial including anti-viral and anti-bacterial; anti-inflammatory, anti-oxidant.

More health benefits of lignans

They may improve menopausal symptoms and consequences like osteoporosis and estrogen-dependent cancers. Flaxseed intake is associated with a significantly reduced risk of breast cancer.

Tannins common food and drink sources

Red wine, green tea, raspberries, black-eyed peas.

Non-hydrolyzable tannins

Condensed tannins (non-hydrolyzable): Also called phiobatannins or proanthocyanidins.

Hydrolyzable tannins

Hydrolyzable tannins- if heated with hydrochloric or sulfuric acid it produces gallic or ellagic acids.

Tannins effects on diabetes 1

They may lower glucose levels by delaying intestinal glucose absorption and an insulin-like effect on insulin-sensitive tissues.

Tannins effects on diabetes 2

They may also delay the onset of insulin-dependent diabetes mellitus by regulating the antioxidant environment of pancreatic beta cells.

Factors influencing the bioavailability of polyphenols

Release of polyphenols from food; digestion of polyphenols; cellular uptake of aglycons and some polyphenols by enterocytes; microbiological fermentation of non-absorbed polyphenols; enzymatic modification; transport in the bloodstream and tissue redistribution; excretion via kidney.Factors influencing the bioavailability of polyphenols Release of polyphenols from food; digestion of polyphenols; cellular uptake of aglycons and some polyphenols by enterocytes; microbiological fermentation of non-absorbed polyphenols; enzymatic modification; transport in the bloodstream and tissue redistribution; excretion via kidney.

Overview of polyphenol absorption and metabolism

In food, polyphenols are generally linked to carbohydrates and organic acids (glycosides). Thus, for bioavailability, cleavage from carbohydrates is necessary.

Beginning of digestion of polyphenols

The digestion of polyphenols starts in the mouth, with amylase being the predominant enzyme. Chewing also decreases particle size.

Why brush border enzymes are needed

The majority of polyphenols need to be cleaved from their sugar moiety by brush border enzymes before uptake into the intestinal cell.

What brush border enzymes do

Enzyme breaks off sugar. Polyphenol without sugar on it can be absorbed into the intestinal cell and then the body.

Where most polyphenols are absorbed

small intestine (not stomach).

Why brush border enzymes are needed

The majority of polyphenols need to be cleaved from their sugar moiety by brush border enzymes before uptake into the intestinal cell.

Benefits of soy vs estrogen treatment

Soy contains phytoestrogens (isoflavones) that can bind to estrogen receptors and provide some of the benefits of estrogen with fewer risks.

• Reduced hot flashes during menopause

• Possible protection against bone loss / osteoporosis

• Possible cardiovascular benefits

• Lower risk of some hormone-related cancers

Soy and menopause symptoms

Soy phytoestrogens may help reduce menopausal symptoms such as hot flashes by interacting with estrogen receptors.

Why soy can act differently than estrogen

Soy contains isoflavones (phytoestrogens) that can act as weak estrogen-like compounds in the body rather than the stronger hormone estrogen itself.

Countries with higher soy intake

Asian countries such as Japan, China, and Korea traditionally consume much higher amounts of soy foods.

Countries with lower soy intake

Western countries such as the United States and many European countries consume much lower amounts of soy foods.

Soy isoflavone intake in Asia

People in countries like Japan and China consume about 15–50 mg of isoflavones per day from soy foods.

Soy isoflavone intake in Western countries

People in Western countries typically consume less than about 3 mg of isoflavones per day.

Molecule that phytoestrogens are similar to

Phytoestrogens are plant-derived dietary compounds with structural similarity to 17-β-oestradiol (E2), the primary female sex hormone.

EFSA conclusion on soy and bone mineral density

It was concluded that the available evidence was not sufficient to establish a relationship between the maintenance of bone mineral density and the consumption of soy isoflavones.

Phytoestrogens and metabolic disease treatment

possible not definitive. The meta-analysis reported an improvement in glucose metabolism and a significant reduction in insulin levels and insulin resistance in menopausal women, by especially genistein.

Soy intake and breast cancer risk

significant trend of decreased risk for breast cancer upon increasing intake of soy food. high doses could be bad for yiu though.

High lignan exposure and breast cancer risk

High lignan exposure has also been associated with a reduced breast cancer risk in postmenopausal women.

Soy intake and lung cancer risk

The consumption of soy food is associated with lower lung cancer risk. too much is risky

Soy isoflavones and thyroid function

are not conclusive. (not harmful but mixed outcomes)

Equol

Equol is a metabolite of daidzein produced by the human intestinal microflora and may be more biologically active (enhances) only some people have. can also harm

Equol producers vs non-producers

Only a limited percentage (30–40%) of the population has the ability to convert daidzein to equol.

Risks and benefits of phytoestrogens

Several potential health benefits of phytoestrogens have been reported but the current evidence on these beneficial health effects is not so obvious that they clearly outweigh the possible health risks.

Benefits mentioned

Phytoestrogens have been associated with:

• Reduced menopausal symptoms (hot flashes)

• Possible cardiovascular benefits

• Possible reduced risk of some cancers

• Potential metabolic and brain health benefits

Possible risks

The article says the evidence does not clearly show that benefits outweigh risks, because phytoestrogens:

• Can bind to estrogen receptors

• May act as estrogen-like compounds in the body

• Could potentially affect hormone-sensitive tissues

Key takeaway

There are both potential benefits and possible risks, and the overall effects are still not completely certain.

Japanese Phenomenon

people in Japan have lower rates of certain chronic diseases, which is thought to be related to their higher lifelong intake of soy (isoflavin) foods and phytoestrogens.

Major classes of phytoestrogens

The four classes of phytoestrogens are: 1. Isoflavones: concentrated mostly in soy products. 2. Lignans: distributed in seeds, whole grains, berries, fruits, etc. 3. Coumestans: found mostly in broccoli and sprouts. 4. Prenyl Flavonoids: not as widely found in foods; available in jackfruit, soybean, licorice, hops. :contentReference[oaicite:0]{index=0}

Non-flavonoid phytoestrogen

Lignans are considered non-flavonoid phytoestrogens.

Flavonoid phytoestrogens

Isoflavones, coumestans and prenyl flavonoids are flavonoids.

Possible health benefits of phytoestrogens

Phytoestrogens have been shown to have many beneficial health effects including preventative or therapeutic actions in carcinogenesis (cancer), atherosclerosis (blood vessel disease), and osteoporosis (bone demineralization). :contentReference[oaicite:3]{index=3}

Overview of absorption of phytoestrogens

The phytoestrogens and their various precursors and metabolite molecules, but not the glucose-containing forms (aka the glycosides), are passively absorbed in the small intestine with other fat-soluble molecules.

Isoflavone digestion characteristic

Isoflavones in soy are not biologically active until after they are digested and absorbed in the small intestine.

Role of enzymes in isoflavone absorption

Enzymes in the small intestine remove glycoside (sugar) residues from the isoflavones, turning them into bioactive forms that can be absorbed.

Isoflavone glycoside form

The glycoside form is not readily absorbed from the gut and have low levels of estrogenic activity.

Phytoestrogen transport in the body

These lipid-soluble nutrients are packed by intestinal cells into chylomicron particles and transferred to the lymphatic circulation before entering the bloodstream and reaching body tissues. :contentReference[oaicite:8]{index=8}

Equol formation

Equol is an isoflavone-derived metabolite formed from daidzein by bacteria in the small intestine and colon. :contentReference[oaicite:9]{index=9}

Equol activity

Equol is more stable, more easily absorbed and has stronger estrogenic activity than other isoflavone metabolites. :contentReference[oaicite:10]{index=10}

Genistein and estrogen receptors

Phytoestrogens are similar enough to bind to the same receptors on our cells that estrogen binds to. :contentReference[oaicite:11]{index=11}

Tissue sensitivity to phytoestrogens

The reproductive tissues contain the highest number of estrogen receptors and would therefore be most sensitive to phytoestrogens

Make sure you understand the relationship between concentration of genistein and ER activation and estrogen.

• Estrogen: strong binding, lower concentration

• Genistein: weak binding, much higher concentration
  ➡ So genistein can still influence ER activation.

Groups with lowest rates of hot flashes during menopause

Women in Asian populations consuming high soy diets

High soy diets and breast cancer risk

significant trend of decreased risk for breast cancer upon increasing intake of soy food.

High lignan exposure and breast cancer risk

High lignan exposure has also been associated with a reduced breast cancer risk in postmenopausal women.

know the slide titled Estrogen properties of soy isoflavones well – info about Genistein and estrogen receptor. Make sure you understand the relationship between concentration of genistein and ER activation and estrogen.

Anthocyanin rich berries

Blueberries, blackberries, raspberries, strawberries and cranberries are rich in anthocyanins.

Health benefits of anthocyanin rich berries

Anthocyanins have antioxidant, anti-inflammatory, anti-cancer and cardioprotective effects.

ORAC

ORAC stands for Oxygen Radical Absorbance Capacity and measures the antioxidant capacity of foods.

Berry antioxidant ranking

Berries have some of the highest antioxidant capacities among fruits and vegetables.

Can prunes beat blueberries in antioxidant capacity

Prunes can have a higher ORAC value than blueberries.

Compound blueberries are particularly high in

Blueberries are particularly high in anthocyanins.

Superfruits

Berries such as blueberries, acai berries and pomegranates are commonly referred to as superfruits.

Beneficial compounds in berries

The beneficial compounds in berries include phenolic compounds such as anthocyanins, flavonols, phenolic acids and tannins.

Common phenolic compounds in berries

Anthocyanins, flavonols, phenolic acids and tannins are some of the most common phenolic compounds found in berries.

Health benefits of berries

Berries have antioxidant, anti-inflammatory, anti-cancer and cardioprotective effects and may improve brain health and metabolic health.

How was gut health defined in the State of the Science article

Gut health is typically defined as absence of gastrointestinal (GI) symptoms (e.g., abdominal pain, diarrhea), disease (e.g., inflammatory bowel disease, CVD, diabetes, colon cancer), and unfavorable GI conditions (e.g., increased permeability, mucosal inflammation).

How blueberries help cardiovascular health

Consumption of anthocyanin-rich berries was associated with lower blood total cholesterol and the pro-inflammatory marker C-reactive protein, and blueberries significantly decreased blood lipids and diastolic blood pressure and improved vascular function. :contentReference[oaicite:1]{index=1}

How many blueberries per week improve cardiovascular health

Consumption of >3 servings per week of strawberries and blueberries compared with ≤1 time per week was associated with a trend towards a 34% lower risk of myocardial infarction. :contentReference[oaicite:2]{index=2}

Uses of berries

Berries have been associated with benefits related to cardiovascular health, pre-diabetes and type 2 diabetes, brain and cognitive function, gut health, and exercise recovery. :contentReference[oaicite:3]{index=3}

Health benefits and uses of goji berries

as a food and traditional medicinal plant

associated with antioxidant activity, immune support, and potential benefits for eye health and general wellbeing.

How are prunes and dried plums related?

Prunes are dried plums, but not all plum varieties can be dried and made into prunes. Only plums that can be sun dried without fermenting while still containing the pit become prunes.