Almost 600 studies - the majority conducted in Russia - have been published on the effects of taxifolin, a powerful flavonoid extracted from Siberian larch. They have shown that taxifolin protects cell membranes, improves capillary activity and blood microcirculation throughout the body and normalises metabolism at a cellular level. It also has anti-inflammatory, hepatoprotective and anti-oedema effects, and reduces both cholesterol levels and the development of blood clots and viscosity. It acts synergistically with, and enhances the effects of vitamin C.
Flavonoids boost the elasticity and ‘leak-tightness’ of vessels
Flavonoids are phenolic compounds present in many plants. Although they were isolated in 1814 by the scientist E. Chevreul, it was 1936 before they were properly discovered - almost by chance - by Hungarian scientist Albert Szent- Györgyi. A friend of his had succeeded in stopping his gums bleeding by taking a crude vitamin C preparation isolated from lemon. When they later began to bleed again, Szent- Györgyi gave his friend a purer form of vitamin C, believing it would produce an even better result but it actually proved ineffective. Szent- Györgyi then gave his friend a fraction of the flavonoid isolated from the original crude vitamin C supplement and his friend’s gums healed completely.
Szent- Györgyi subsequently highlighted the ability of flavonoids to reduce the permeability of blood vessels and their synergistic action with vitamin C, which is why he originally gave them the name ‘vitamin P’ for ‘permeability’. Flavonoids do not, however, have vitamin activity. The Hungarian scientist was awarded the Nobel Prize for his research on vitamin C and on the biochemical properties of flavonoids. These compounds help to boost blood vessels’ elasticity and ‘leak-tightness’ and thus their resistance. They also act as potent antioxidants, protecting the body from oxidative stress and free radical attack, as well as boosting the effects of vitamin C.
Taxifolin is a powerful flavonoid
It was in the mid-1950s that scientists for the first time extracted and described taxifolin, or dihydroquercetin, which is an analogue of quercetin or rutin but with somewhat different properties. It displays vitamin P activities, boosting vascular membranes and reducing allergic and inflammatory reactions, and also has many properties not shared by the majority of other bioflavonoids. Taxifolin therefore exerts a much more potent antioxidant effect than most flavonoids.
Most research into taxifolin has been carried out in Russia at the Institute of Aviation and Space Medicine, the Military Medical Academy (named after SM Kirov), the Central Military Hospital (named after NN Burdenko), the 6th Central Military Clinical Hospital and the Institute of the Human Brain at the Russian Academy of Sciences.
Taxifolin inhibits oxidative stress and inflammation
Taxifolin has been shown to be a powerful neutraliser of free radicals, capable of destroying two of the most dangerous forms present in the human body: the superoxide and peroxide radicals. It also works to protect red and white blood cells. Studies show that it protects white blood cells from environmental damage, and that in red blood cells it prevents oxidative cell death.
The antioxidant effect of taxifolin was studied in Wistar rats with methane tetrachloride-induced experimental hepatitis. The animals were divided into three groups: 9 were given methane tetrachloride subcutaneously for four days, another 9 were given taxifolin (100mg/kg) for four days before the first injection of methane tetrachloride and for 14 days after it, and the third group were not given anything. The content of products of lipid peroxidation reacting with thiobarbituric acid in those given just the methane tetrachloride injections increased 1.5 fold compared with the controls and those given taxifolin. Similarly, the antioxidant activity of their plasma was 1.8-2 times lower than that of the other animals 1
Capillaries and functional disorders
Capillaries are very small vessels, 5-8 microns in diameter, comprising just one endothelial cell layer with a basal lamina and a few collagen fibres. It is at the capillary level that all exchanges between the blood and vascularised tissues take place. These vessels are also the link between the arterial and venous systems. Several thousand kilometres of capillaries provide the oxygen and nutrients necessary for all the body’s cells and simultaneously remove the resulting waste products.
Capillaries do not exist in an isolated state but form an organised network that moves between arterioles and venules.
If capillary circulation is damaged, cells become starved of oxygen, and are ultimately destroyed. Capillary circulation problems are at the root of many disease processes.
Russian doctor A.S. Zalmanov theorised that human health could be improved by helping to increase the work capacity of the capillaries: “It is not a question of finding treatments for particular diseases and repairing damage to organ function without taking into account the origins of the diagnosis. It is the capillaries which are at the root of these functional problems”.
Microcirculation problems and arterial hypertension
In arterial hypertension, the system of microcirculation responsible for organ blood irrigation quickly becomes damaged. This has huge clinical significance in terms of the blood supply to the heart, brain and kidneys. In hypertensive patients, inadequate microcirculation occurs as a result of a decrease in the number and density of capillaries.
At the level of microcirculation, important changes in the blood’s rheological properties take place which cause increased blood viscosity. Such rheological blood changes associated with a reduction in microvessels are responsible for a decrease in irrigation and oxygen supply to tissues as well as an increase in peripheral resistance and arterial pressure.
Taxifolin has various properties likely to be of benefit to those with hypertension. Clinical studies have shown that it improves the elasticity of erythrocytes such that they are able to easily penetrate even the most delicate blood vessels. Elevations in pressure no longer occur as a matter of course and thus the risk of stroke is drastically reduced. Taxifolin also decreases blood viscosity and improves microcirculation at capillary level.
Various studies have been conducted in this context in Russia. Taxifolin’s effects were investigated in two groups of 40 patients with neuro-circulatory asthenia (a form of tachycardia) with hypertonia and arterial hypertension. While both groups were given a hypotensive, the second group also received an additional daily dose of 40mg of taxifolin. In the first group, a clear hypotensive effect was observed between the third and fourth days of treatment but 17% of participants needed an increase in their dose of medication. The same hypotensive effect was seen in the second group but sooner - between the first and second days of treatment - and none of this group needed their medication increased.
In another trial, 80 males aged 23-52 with neuro-circulatory asthenia of hypertonic type or arterial hypertension with extrasystolic arrhythmia, were given a complex treatment for arrhythmia, with 40 of the participants receiving an additional 40mg/day of taxifolin. Efficacy was measured on the third, fifth and eighth days of treatment. The anti-arrhythmia effects were observed one or two days earlier in those taking the taxifolin and the effect was also 86.7% greater. This trial demonstrates that taxifolin has a clear hypotensive and anti-arrhythmia effect, with no side-effects.
100 patients with stage 1 or 2 hypertension on stable medication were randomly divided into two groups, receiving either taxifolin (68 patients) or a placebo (42 patients).
- a significant reduction over three months in systolic and diastolic blood pressure in both groups, and a decrease in the frequency of cardiac contractions in the group given taxifolin ;
Beneficial in the treatment of cerebrovascular disease
- a stable hypotensive effect in daytime systolic and diastolic blood pressure in both groups after six weeks, and a significant decrease in night-time systolic pressure in the taxifolin group only, by the end of the study ;
- a reduction in stagnant processes in microcirculation flow and an improvement in microcirculation in the taxifolin group. Supplementation with taxifolin partly reduced rheological damage and haemodynamic problems in the microvessels ;
- after six weeks of treatment, a normalisation of endothelial function in the taxifolin group.
Arterial hypertension is a major risk factor for stroke - present in 78.2% of cases - followed by age, diabetes, smoking, atherogenic changes in lipoproteins and hypertrophy of the left ventricle.
Studies have been conducted at the National Research Institute of the Human Brain at the Russian Academy of Sciences to assess the effects of taxifolin in individuals with cerebral circulation problems.
29 patients with an average age of 67.6, suffering from discirculatory encephalopathy, were given 80mg/day of taxifolin for 18 to 21 days. Twelve had suffered an ischaemic stroke.
Study methods included:
- evaluation of data on the patients’ condition including a questionnaire;
- clinical examination with an assessment of neurological symptoms, asthenia and psycho-emotional and vascular-vegetative problems;
- verification of the main organ anomalies in the central nervous system;
- assessment of vegetative tone, central haemodynamics and external respiration indices.
Taxifolin supplementation was shown to improve certain problems, particularly headaches, insomnia, asthenic and vascular-vegetative problems as well as vertigo. Improvements were more significant in patients with encephalopathy linked to stroke-associated posterior vascular problems. It also reduced emotional lability, irritability, anxiety, low mood, hypochondria and fixation on personal feelings. Again, with the exception of low mood and hypochondria, these improvements were greater in stroke patients. Indices of intellectual memory activity were better in two thirds of patients following administration of taxifolin, as were concentration and attention. Patients’ memory improved by 70% and volume of operational memory increased in 66.7% of cases.
The data obtained from studies on middle-aged patients with discirculatory encephalopathy shows that taxifolin exerts moderate effects in relation to the central mechanisms of functional vegetative and psycho-emotional regulation.
Two clinical studies were conducted on 52 patients to evaluate the effects of 21 days’ administration of taxifolin combined with vitamin C on patients with cerebral circulation problems. The supplementation resulted in decreased blood viscosity and clot-forming tendencies, improved memory, attention and mental performance, reduced vertigo, normalised sleep patterns, relief from headaches and less fatigue. No such changes were observed in a placebo group 2, 3
Taxifolin and cardiovascular disease
Scientists have shown that taxifolin inhibits lipid peroxidation, a process that often leads to atherosclerosis4
. In an animal study, taxifolin inhibited peroxidation of serum and hepatic lipids following toxic ionising radiation5
. Its inhibitory effects are boosted by vitamins C and E6
. By preventing the peroxidation of potentially dangerous low density lipoproteins, taxifolin helps prevent atherosclerosis.
Reducing raised low density lipoprotein levels is a major objective of anti-cholesterol treatments and of the statins prescribed by doctors. Studies suggest that taxifolin may be helpful in therapeutic efforts to lower LDLs. In fact, it may inhibit the formation of apoprotein B, one of the main components of LDL, reducing both lipid production in the liver as well as secretion of apoprotein B, and increasing that of apoprotein A. 7
Additional studies have shown that taxifolin lowers serum and hepatic lipid levels and cholesterol concentrations in rats, its action proving much more effective than that of quercetin.
In addition, animal studies have shown that taxifolin lowered elevated blood pressure and normalised an electric measurement associated with activation of cardiac ventricles.
Prevents complications of diabetes
Diabetes can have serious consequences, particularly for the cardiovascular system and the eyes. Scientists have noted that type 2 diabetics are at higher risk of arterial disease. This is partly because type 2 diabetes increases the ability of white blood cells called neutrophils to adhere to the blood vessel lining or endothelium8
. This may contribute to the development of vascular disease throughout the body, particularly in the essential blood vessels of the heart. A Russian study found that taxifolin inhibits the pro-inflammatory activity of neutrophils in type 2 diabetics and may therefore help protect the vascular system from the disease’s harmful effects 9
In diabetics, taxifolin has been shown to protect against two common causes of sight loss: macular degeneration and cataract. The former develops when the area of the retina responsible for detailed vision starts to deteriorate. Taxifolin promotes blood flow to this region of the eye, providing protection against loss of vision. In addition, by inhibiting the activity of an enzyme in the lens, it may also help prevent cataract formation in diabetics.
Maintains a healthy central nervous system
The brain and central nervous system are particularly vulnerable to the harmful effects of free radicals. Over the years, radical damage can accumulate in the brain, leading to cognitive decline and diseases such as dementia or Alzheimer’s disease. Taxifolin offers essential protection to the brain and neurons.
In order to establish how taxifolin protects the brain from such damage, scientists used an animal stroke model. They found that taxifolin inhibits the expression of enzymes that lead to inflammation. In addition, it helps prevent inflammatory white cells from attacking and adhering to vulnerable areas of the brain. These actions help provide vital neuro-protection against free radical-induced oxidative damage which often occurs when the brain receives insufficient blood or oxygen10, 11
Alongside the cognitive decline that frequently accompanies ageing, essential functions such as perception, thought, language and awareness can also be negatively affected. Protecting the areas of the brain responsible for these functions is another important benefit of taxifolin. In one study, researchers noted that taxifolin was preventing free radicals from causing oxidative damage to the crucial nerve cells that control these functions12
By protecting brain cells and the central nervous system, taxifolin may help prevent some of the most devastating changes associated with the ageing process.
Protection against liver damage and hepatitis
A number of chemicals used in industry and commerce, such as dioxins, dibenzofurans and carbon tetrachloride, act like poisons in the liver. Some can cause liver toxicity and hepatitis by promoting hepatic lipid peroxidation. Due to its significant antioxidant potency, taxifolin may protect the liver against exposure both to these toxins and as well as to viruses. When rats were given taxifolin for four days before being exposed to chemicals formerly used in the dry cleaning and refrigeration industries, they were protected against these toxins’ hepatitis-inducing effects 13
In addition, in a mouse model of liver damage, taxifolin was shown to be more effective than vitamin E at inhibiting the biochemical changes that lead to hepatitis. Specifically, taxifolin blocked production of the pro-inflammatory tumour necrosis factor-alpha, as well as infiltration of immune system cells.
Taxifolin shows promise in combatting hepatitis A - a virus usually contracted by eating contaminated food. In the laboratory, taxifolin inhibited the replication and pathogenic effects of the virus 14
Supplementing with taxifolin thus provides important benefits for the liver by helping to protect it from the damaging effects of exposure to toxins and viral hepatitis infection.
Boosts the immune system
Studies suggest that taxifolin may help combat serious infections such as pneumonia or HIV.
Researchers examined the effects of taxifolin on patients suffering from acute pneumonia. When subjects following a standard treatment supplemented with an antioxidant formula containing taxifolin, they recovered better from the symptoms of lung inflammation than patients receiving the traditional treatment alone 15
Preliminary studies seem to indicate that taxifolin may help combat the HIV virus. It was recently found to inhibit the activity of an enzyme used by viruses such as HIV to replicate their genetic 16
Synergistic action with vitamin C
Taxifolin boosts the beneficial effects of vitamin C by increasing the duration of its biological activity, stimulating its regeneration and slowing down its elimination from the body. In Russia, a complex of taxifolin and vitamin C is a popular treatment for many diseases where oxidative stress is the underlying mechanism.
1. Teselkin Yu O. et al., Dihydroquercetin as a mean of antioxidant defence in rats with tetrachloromethane hepatitis, Phytotherapy Research, 11 May 2000, vol. 14, issue 3, 160-162.
2. Plotnikov M.B. et al., Hemorheological and antioxidant effects of Ascovertin in patients with sclerosis of cerebral arteries, Clin. Hemorheol. Microcirc., 2004, 30(3-4): 449-52.
3. Plotnikov M.B. et al., Clinical efficacy of a novel hemorheological drug ascovertin in patients with vascular encephalopathy, Zh. Nevrol. Psikhiatr. Im SS Korsakova, 2004, 104(12): 33-7.
4. Kravchenko L.V. et al., Effects of flavonoids on the resistance of microsomes to lipid peroxidation in vitro and ex vitro, Bull. Exp. Biol. Med., 2003 Dec, 136(6): 572-5.
5. Teselkin Yu O. et al., Influence of dihydroquercetin on the lipid peroxidation of mice during post-radiation period, Phytotherapy Research, 1998, 12: 517-9.
6. Vasiljeva O.V. et al., Effect of combinated action of flavonoids, ascorbate and alpha-tocopherol on peroxidation of phospholipid liposomes induced by Fe2 + ions, Membr. Cell. Biol., 2000, 14(1): 47-56.
7. Theriault et al., Modulation of hepatic lipoprotein synthesis and secretion by taxifolin a plant flavonoid, Journal of Lipid Research, vol. 41, 1969-1979. December 2000.
8. Van Oostrom A.J. et al., Increased expression of activation markers on monocytes and neutrophils in type 2 diabetes, Neth. J. Med., 2004 Oct, 62(9): 320-5.
9. Fedosova N.F. et al., Mechanism underlying diquertin-mediated regulation of neutrophil function in patients with non-insulin-dependant diabetes mellitus, Bull. Exp. Biol. Med., 2004 Feb, 137(2): 143-6.
10. Wang Y.H. et al., Taxifolin ameliorate cerebral ischemia-reperfusion injury in rat through its anti-oxidative effect and modulation pf NF-kappa B activation, J. Biomed. Scien., 2006 Jan, 13(1): 127-41.
11. Wang Y.H. et al., Prevention of macrophage adhesion molecule-1dependant neutrophil firm adhesion by taxifolin through impairment of protein kinase-dependant NADPH oxidase activation and antagonism of G protein-mediated calcium influx, Biochem. Pharmacol., 2004 June 15, 67(12): 2251-62.
12. Dok-Go H. et al., Neuroprotective effects of antioxidative flavonoids, quercetin, dihydroquercetin and quercetin 3-méthyl ether isolated from Opuntia ficus-indica var. Saboten, Brain Res., 2003 Mar 7, 965(1-2):130-6.
13. Teselkin Yu O., Dihydroquercetin as a mean of antioxidative defence in rats with tetrachloromethane hepatitis, Phytother. Res., 200 May, 14(3): 495-502.
14. Biziagos E. et al., Effect of antiviral substances on hepatitis A virus replication in vitro, J. Med. Virol., 1987 May, 22(1) : 57-66.
15. Kolhir V.K. et al., Use of a new antioxidant diquertin as adjuvant in the therapy of patients with acute pneumonia, Phytotherapy Research, 1998, 12: 606-8.
16. Chu S.C. et al., Inhibitory effects of flavonoids on Moloney murine leukemia virus reverse transcriptase activity, J. Nat Prod., Feb 1992, 55(2): 179-83.