Print Digg


The Fabulous Flavonoids

Friday, August 15, 2014

Flavonoids, also called bioflavonoids and classified as phytochemicals, were once called vitamin P, based on the clinically suggested effect they have on the permeability of capillaries. Unfortunately, that name fell out of favor a number of years ago.

They have also been referred to as "nature's biological response modifiers," because they are able to modify the body's reaction to vascular disease, cholesterol reduction, carcinogens, allergens and viruses.  

Their ability to help inhibit angiogenesis, as well as protect and strengthen the new capillaries formed by angiogenesis (neovascularization) can be particularly important to AMD, diabetic retinopathy, and cancer patients. 

Flavonoids are synthesized by and widely distributed in plants. Their jobs are many; the most important, supplying the pigments for flower coloration producing yellow, red and blue pigmentation in petals designed to attract pollinators. They also protect plants from microbes and fungi. 

According to the nutrition science research team at the Linus Pauling Institute at Oregon State University, many of the biological effects of flavonoids appear to be related to their ability to modulate gene-based cell-signaling pathways associated with degenerative disease, rather than their antioxidant abilities. 

Biological Activities

While flavonoids have not proven to have the antioxidant abilities once thought, they are proving to chelate (bind) iron and copper ions to specific proteins, which limits their participation in biochemical reactions that produce free radicals. This, too, could be important to AMD and cancer patients, since excess copper is necessary for angiogenesis to take place. 

Cell-Signaling Pathways

Many of the biological effects of flavoniods fare now related to their ability to modulate cell-signaling pathways.

Effective signal transduction requires proteins known as kinases that catalyze the phosphorylation of target proteins at specific sites. These proteins ultimately affect the activity of transcription factors that bind to specific response elements on DNA and promote or inhibit the transcription of various genes. This activity is also very important to those at higher risk of genetic degenerative disease, including AMD and Alzheimer’s. 

The Big Three 

Quercetin: Quercetin is widely distributed in nature. Foods rich in quercetin include black and green tea, apples, onions and especially red onions, red grapes, citrus fruits, tomatoes, broccoli and other leafy green vegetables, as well as raspberry and cranberry. It’s used to treat conditions of the heart and blood vessels including hardening of the arteries (atherosclerosis), high cholesterol and most circulation problems.  

Rutin: This flavonoid is a glycoside bound by sugar to quercetin and the disaccharide rutinose. It’s found in apples and fruit rinds, especially citrus fruit rinds. It is also the primary flavonoid found in clingstone peaches. It inhibits platelet aggregation, inhibits aldose reductase activity, the enzyme normally present in the eye and associated with diabetic complications. Rutin also strengthens the capillaries and attaches to the iron ion, preventing it from binding to hydrogen peroxide, which creates highly reactive free radicals that damage cells, particularly in the eye. 

According to the Harvard Health Letter, their researchers discovered rutin's antithrombotic property when they screened a set of 5,000 compounds for their ability to block the action of a key protein involved in the formation of vessel-clotting blood clots—suggesting that rutin could be effective at helping prevent both the arterial clots that cause heart attacks, strokes and the venous clots that cause deep-vein thrombosis and pulmonary embolism.  

Hesperadin: Hesperadin is a water- soluble type of flavonoid called a flavanone, due to the presence of a specific sugar molecule in its structure. It's found in all citrus fruits, but it is the predominant flavonoid in lemons and oranges. It’s been implicated in many of their beneficial effects including vascular protection and cholesterol lowering, and some studies suggest anticancer effects, and to up regulate the LDL receptors. This leads to the reduced assembly and secretion of apoB-containing lipoproteins, and enhanced reuptake of those lipoproteins lowers cholesterol levels.

Ellen Troyer, with Spencer Thornton, MD, and the Biosyntrx staff


Since the flavonoids are a lot more than a plant-based pretty face, and because they play an important role in gene related cell-signaling and vascular health, and since cell signaling and vascular disease are so often associated with macular degeneration and neurodegenerative disease, it makes biological sense to recommend diets high in flavonoids, as well as flavonoid supplementation to all those at increased risk of gene-related degenerative disease, including macular degeneration, dementia, Alzheimer’s, heart disease, stroke and cancer.  

The Biosyntrx multiple, Eye & Body Health (formerly Macula Complete) includes 300 mg of our bioflavonoid complex. The complex includes generous amounts of quercetin, rutin and hesperidin.


Relative impact of flavonoid composition, dose and structure on vascular function: A systematic review of randomised controlled trials of flavonoid-rich food products. Kay CD, Hooper L, et al. Mol Nutr Food Res. 2012 Sep 19 [abstract]

Phytochemicals and their impact on adipose tissue inflammation and diabetes. Leiherer A, Mundlein A, Drexel H. Vascul Pharmacol 2012 Sep 12

The Flavonoid Quercetin Inhibits Pancreatic Cancer Growth In Vitro and In Vivo. Angst E, Park JL, et al. Pancreas 2012 Sept 20. [abstract] 

Inhibition of advanced glycation end-product formation on eye lens protein by rutin. Muthenna P, Akileshwari C, et al. Br J Nutr 2012 Apr; 107(7): 941-9 [abstract]

Barrier protective effects of rutin in LPS-induced inflammation in vitro and in vivo. Lee W, Ku SK, Bae JS. Food Chem Toxicol 2012 Sept. 50(9): 3028-55. [abstract]

The rutin catobolic pathway with special emphasis on quercetinase. Tranchimand S, Brouant P, et al. Biodegradation 2010 Nov;21(6): 833-59 [abstract]

Hesperidin inhibited acetaldehyde-induced matrix metalloproteinase-9 gene expression in human hepatocellular carcinoma cells. Yeh MF, Kao St, et al. Toxicol Lett 2009 Feb 10;184(3): 204-10. [abstract]

Bioavailability of orally administered water-dispersible hesperetin and its effect on peripheral vasodilation in human subjects: implication of endothelial function of plasma conjugated metabolites. Ikemura M, Saski Y. et al. Phytother Res. 2012 Sep, 26(9): 1272-7/ [abstract]

Systematic phosphorylation analysis of human mitotic protein complexes. Hegermann B, Hutchins JR, et al. Sci Signal 2011 Nov 8,4(198): rs12 [abstract]