Phytonutrients - Proanthocyanidins

Question 1

Proanthocyanidins

Answer 1

Proanthocyanidins are known as condensed tannins and are formed from building blocks including catechin and epicatechin. They are predominant in the seeds and skin of grapes

Question 2

Food sources:

Answer 2

• Grapes (skin and seeds).
• Cranberries, blueberries, elderberry, bilberries.
• Cocoa.
• Apples, cinnamon, cashews.
• Maritime pine bark (pycnogenol).
  Anthocyanidin from Greek anthos, for flower + kyanos–blue colouration
  Tannins = polyphenols that have a typical mouth-puckering, sour taste

Question 3

Functions and Therapeutic uses:

Answer 3

• Cardiovascular health
• Immune-modulation
• Neurological health
• Anti-cancer

Question 4

Cardiovascular health:

Answer 4

Functions:
* Potent antioxidant properties -preventing LDL oxidation.
* Enhance nitric oxide promoting vasodilation.
* Improve circulation and capillary integrity. Protect capillaries from oxidative stress.
Therapeutic uses:
* Cardiovascular disease prevention.
* Atherosclerosis.
* Hypertension.
* Peripheral oedema.
* Diabetic retinopathy and neuropathy.

Question 5

Immune-modulation:

Answer 5

Functions:
* Stimulate lymphocyte and macrophage activity.
* Stabilise mast cells —inhibit histamine-producing enzymes.
Therapeutic uses:
* Immune support.
* Anti-allergic: Allergic rhinitis, asthma / eczema.

Question 6

Neurological health:

Answer 6

Therapeutic uses: Neuroprotective properties against:
* Alzheimer’s by inhibiting beta-amyloid aggregation.
* Parkinson’s by protecting dopamine-producing cells.

Question 7

Anti-cancer:

Answer 7

Therapeutic uses: Proanthocyanidins have anti-cancer properties:
* They can inhibit cell proliferation and induce apoptosis and cell cycle arrest.
* Research suggests an inhibitory effect on cancer stem cells, which are central to tumour initiation and metastasis.

Question 8

Dosage:

Answer 8

• A plant-rich diet is considered to provide proanthocyanidins at an amount that promotes general health.
• For specific health conditions, supplemental doses based on grape seed and pine bark extracts can be used (proanthocyandins 100–300 mg daily).

Question 9

Safety and interactions:

Answer 9

• Generally recognised as safe and well tolerated.
• Monitor with antihypertensive medication. Caution with anti-coagulant medications —may have additive effects.