Usage 1: Physiological function of α -linolenic acid: enhancing intelligence, improving memory, protecting eyesight and improving sleep. Inhibit thrombotic diseases and prevent myocardial infarction and cerebral infarction. Reduce blood fat. Lower blood pressure. Inhibit hemorrhagic stroke. Prevent allergies. γ -linolenic acid can be used to treat hypertension, as an adjuvant therapy for diabetes, improvement of zinc deficiency and sensitization of γ -ray radiotherapy, and also has different therapeutic effects on Huntington's chorea, phenylketonuria, menopausal syndrome, Parkinson's disease, asthma, eczema, hyperparathyroidism and other diseases.
Use 2: Nutritional supplement.
Usage 3: γ -linolenic acid is an essential fatty acid for human body. As a nutritional fortifier, it can be used to fortify γ -linolenic acid drinks, blended oil, milk and dairy products in China, and the dosage is 2% ~ 5%.
physiological function
α -linolenic acid, as energy supply for growth, cell metabolism and muscle movement, is only a part of its function, and it is more a structural substance and a metabolic regulatory substance, which plays a structural function and regulatory function.
Structural function
α -linolenic acid and its derived long-chain polyunsaturated fatty acids are important components of all cell membranes and mitochondrial membranes. The fatty acids in membrane phospholipids directly affect membrane functions, such as enzyme catalytic reaction, receptor activity, transmembrane transport and metabolic rate. When the content of ω-3 unsaturated fatty acids in cell membrane increases, the fluidity and plasticity of the membrane increase. There is a positive correlation between membrane fluidity and glucose transport, which can increase the sensitivity of insulin to regulate glucose metabolism and help improve glucose tolerance and correct insulin resistance. The increase of fatty acid saturation in cell membrane can lead to the decrease of metabolic rate, obesity and physical fatigue. The plasticity of membrane plays an important role in resisting arteriosclerosis and restoring vascular elasticity.
The structural function of ω-3 polyunsaturated fatty acids (ω-3 PUFA) in the nervous system is even more indispensable. The deficiency of ω-3 PUFA in fetus and infant can lead to the hypoplasia of brain, nerve and retina, which has a negative impact on the development of intelligence and vision. The deficiency of ω-3 PUFA in adults is also prone to mental and visual fatigue. It is generally believed that the function of ω-3 PUFA in brain, nerve and retina is that it can provide a highly fluid membrane environment.
Regulation function
Some physiological functions of α -linolenic acid are realized by regulating the activities of related enzymes. α -linolenic acid changes the activity of some membrane-bound enzymes in biofilm, such as adenosine cyclase, 5, nucleotidase and Na-K-ATPase, which are sensitive to fatty acids. The change of enzyme activity is also an adaptation to the change of membrane structure.
The hypolipidemic effect of α -linolenic acid is achieved by regulating metabolic rate on the one hand, and by inhibiting related fat and glycerol synthetases and cholesterol synthetases on the other hand. α -linolenic acid can reduce the activity of HMG-CoA, the rate-limiting enzyme of cholesterol synthase, and reduce the production of cholesterol. α -linolenic acid inhibits fatty acid synthase (including fatty acid synthase, CoA- carboxylase, diacylglycerol acetyltransferase, etc.) and strengthens β -oxidation in mitochondria, which reduces the synthesis of triglycerides and increases consumption.
α -linolenic acid inhibits the metabolism of ω-6 series PUFA through competitive inhibition, reduces the synthesis of prostaglandin PGE2, prostacyclin PGI2, thromboxane TXA2 and leukotriene LT4, and increases the corresponding metabolites of ω-3 series PUFA, thus producing numerous biological regulatory effects, such as anti-inflammatory, antithrombotic and antiallergic effects.
Physiological demand
Because the amount of ω-3 fatty acids ingested by different regions and different living habits is different, the demand for α -linolenic acid is also different. In the diet structure of coastal areas, marine food accounts for a large proportion, and the intake of EPA and DHA, both ω-3 unsaturated fatty acids, is relatively large, and the demand for α -linolenic acid as their parent is relatively reduced. According to the ideal ratio of energy supply, ω-3 fatty acids should be able to provide 1% of energy every day, that is, 20 kilocalories per day, which is equivalent to 2.2 grams of α -linolenic acid, and the intake of linoleic acid should be controlled below 8.7 grams to reduce its inhibition on the transformation of linolenic acid into EPA and DHA. Because there is competition inhibition between ω-6pufa and ω-3pufa, the ω-6/ω-3 ratio is paid attention to. Some countries and organizations use ω-6/ω-3 ratio to express the recommended dietary intake of PRFA, such as WHO's recommendation ω-6/ω-3 = 5 ~10:1,Sweden's recommendation ω-6/ω-3 = 5:1,and Japan's recommendation ω-6/ω.
Important efficacy
With the deepening of research, the relationship between α -linolenic acid and health and diseases has attracted the attention of scholars at home and abroad. Although the amount of α -linolenic acid resources is small, and there are few kinds of food that can be ingested, their physiological activities are indispensable to the human body. Based on the research results of global medicine and nutrition, α -linolenic acid has the following basic functions:
Regulation of blood lipid
Dyslipidemia is a serious threat to human health and life, and it is an important risk factor for the formation and progress of atherosclerotic lesions. It has been proved that lipid-regulating drugs can delay the occurrence of atherosclerotic events (such as myocardial infarction and stroke). Many experiments show that α -linolenic acid can reduce serum total cholesterol (TC), triglyceride (TG), low density lipoprotein and very low density protein, and increase serum high density lipoprotein.
In the mechanism of α -linolenic acid lowering serum cholesterol, it is also important to inhibit endogenous cholesterol synthesis besides increasing cholesterol excretion. HMG-CoA is the main rate-limiting enzyme for cholesterol synthesis, and α -linolenic acid inhibits its activity and reduces cholesterol synthesis. Tield et al. found that the intake of α -linolenic acid can decrease the activity of HMG-CoA reductase in rabbit liver and increase the activity of ACAT. α -linolenic acid inhibits the lipase synthesis system and strengthens the β -oxidation in mitochondria, which reduces the synthesis of triglycerides and increases the consumption. α -linolenic acid can reduce the blood lipid of rabbits, but there is no accumulation of lipid in the liver. However, linoleic acid and γ -linolenic acid belonging to ω-6pufa can also reduce blood lipid, but they mainly promote the transfer of lipid from blood to liver, which leads to fatty liver.
At the same time, some papers report that different types of ω-PUFA in deep-sea fish oil have different lipid-lowering effects. EPA mainly plays a role in lowering triglycerides, while DHA plays a role in lowering cholesterol. As their parent, α -linolenic acid can play a comprehensive role in lowering blood lipid and expelling fat.
Prevention of infarction
From the mechanism, there are two main types of thrombosis, one is lipid embolus, and the other is blood coagulation. Most antithrombotic drugs only have an effect on one factor, while the antithrombotic effect of α -linolenic acid is complete and comprehensive.
Under the ultra-high power electron microscope, through the observation of peripheral blood, cholesterol crystals and chyle granules can be clearly seen, and some patients also have large plaques. These cholesterol crystals and lipid plaques adhere to the inner wall of blood vessels, which can form lipid thrombosis. Hyperlipidemia is the main cause of lipid thrombosis. Free cholesterol and triglycerides can't be dissolved in blood, but exist in the form of crystals or granules. When the inner wall of blood vessels is damaged, these lipid substances can adhere to the inner wall of blood vessels, form large plaques after long-term accumulation, and cause atherosclerosis. α -linolenic acid can reduce cholesterol, triglyceride, LDL and VLDL, increase HDL, and play an antithrombotic role. After taking 1.2g/d α -linolenic acid 120 days, the density of cholesterol crystals can be significantly reduced under the microscope, and large lipid plaques can disappear.
Platelet aggregation is the most important link in the process of blood coagulation. Thromboxane TXA2 can cause platelet aggregation, while PGI2 plays an antagonistic role. Arachidonic acid AA generates PGI2 under the action of cyclooxygenase, and it also generates TXA2. EPA competes with AA for cyclooxygenase to generate PGI3 and TXA3, which reduces the generation of PGI2 and TXA2. PGI3 and PGI2 have considerable antagonistic activity to TXA2, but TXA3 has no platelet aggregation activity, so EPA. At the same time, ω-3 PUFA can stabilize myocardial membrane potential, reduce ventricular arrhythmia and sensitivity, and prevent arrhythmia, especially fatal ventricular arrhythmia caused by ischemia.
Reducing viscosity and increasing oxygen
In most cases, coronary heart disease and cerebral ischemia are caused by thrombus, but blood viscosity is also a factor that cannot be ignored. Some patients with coronary heart disease and cerebral ischemia have no obvious arterial embolism, which is caused by the increase of blood viscosity and the decrease of blood oxygen carrying capacity, resulting in insufficient blood supply to myocardium and brain and peripheral circulation disorder, showing symptoms such as palpitation, chest tightness, dizziness, insomnia, memory loss and numbness of limbs.
Hyperviscosity can have two meanings: first, it is reflected in the fluidity of blood, that is, the rheological meaning of blood, which can be measured by viscometer. The decrease of blood fluidity slows down the flow of blood in blood vessels, leading to tissue ischemia and increasing the burden on the heart. Second, it is reflected in the aggregation of red blood cells, that is, the adhesion of red blood cells. Under the high-power microscope, it can be seen that red blood cells are overlapped. In this state, the total surface area of red blood cells that can carry oxygen is reduced, and the oxygen carrying capacity is reduced, and the tissues also have hypoxia symptoms. The increase of various solutes in the blood makes the blood viscosity increase and the fluidity decrease. The solutes are mainly some protein, such as glycoprotein, lipoprotein, fibrinogen and collagen. However, the change of the composition of the erythrocyte membrane reduces the charge on the membrane surface, and the repulsion between cells is not enough to separate the cells and cause adhesion.
There is no specific drug for blood viscosity. In this respect, α -linolenic acid has its unique function. α -linolenic acid can regulate the metabolism of sugar, fat and protein, reduce the level of soluble protein in blood and increase the fluidity of blood. The effect can be seen after supplementing α -linolenic acid for about 90 days. When the proportion of α -linolenic acid in cell membrane phospholipids increases, the fluidity of the membrane increases, and at the same time, the electric charge on the surface of the cell membrane increases, and the adhesion between cells can be obviously improved. Generally, the adhered cells are obviously dispersed after 30 days of α -linolenic acid supplementation. The patients with hyperviscosity were supplemented with α -linolenic acid at a dose of 1.5g/d for 90 days, and all the indexes were restored to normal, while the symptoms such as palpitation, chest tightness, dizziness, insomnia, memory loss and numbness of limbs were obviously improved, and the effective rate was over 90%.
For diabetes
α -linolenic acid can promote insulin secretion by insulin β -cells and keep insulin stable in blood, reduce the resistance of target cells to insulin, improve the sensitivity of insulin receptors on cell membrane and reduce the antagonism of insulin.
When suffering from diabetes, the decomposition of fat in the body is accelerated, and the disorder of lipid metabolism causes the increase of blood lipid, which leads to complications such as arteriosclerosis, hyperlipidemia, fatty liver and hypertension. In addition, excessive decomposition of fat will produce ketone bodies. If ketone bodies exceed the utilization limit of the body and accumulate in large quantities in the body, ketoacidosis will occur. α -linolenic acid can regulate lipid metabolism, inhibit complications and reduce the probability of acid and ketone poisoning in human body. At the same time, the protection and enhancement of α -linolenic acid on human organs and nervous system are of great benefit to diabetic patients.
reduce blood press
α -linolenic acid and its metabolites EPA and DHA can reduce blood pressure in patients with hypertension. Taking1.2g daily can reduce systolic blood pressure, diastolic blood pressure and average arterial pressure by 10mmHg, while normal blood pressure is almost unaffected. The hypotensive mechanism of ω-3 PUFA is thought to be the response of endogenous vasoactive substances to blood vessels, such as the vasodilating effect of PGI3, which stimulates endothelial cells to release NO, and at the same time, α -linolenic acid can reduce the content of neutral fat (cholesterol and triglyceride) in plasma.
lose weight
α -linolenic acid is different from any other drugs in reducing the weight of obese patients. It is mainly achieved through the following two ways: first, increasing metabolic rate; The second is to inhibit the synthesis of triglycerides and increase the excretion of various lipids in the body. But to achieve the effect of losing weight, the dosage should be increased relatively.
Suppress allergic reaction
The incidence of pollen allergy, food allergy, specific eczema and asthma is increasing. There are two possible reasons for this situation. First, the allergens that people can contact are increasing. Second, the body is hyperactive. Mast cells and neutrophils play an important role in the process of allergy. As soon as allergens enter the human body, they combine with mast cells, which are stimulated to release histamine and leukotrienes (LT4). In addition, platelet activating factor is released from neutrophils. These active substances lead to various symptoms of allergy, such as dyspnea, increased secretion, rhinitis and so on.
Changes in the proportion of different kinds of essential fatty acids in food can cause allergic reaction in the body. Because 4-series leukotrienes LT4(LTB4, LTC4, LTD4, LTE4) are produced by arachidonic acid of ω-6pufa, while 5-series leukotrienes LT5(LTB5, LTC5, LTD5, LTE5) are produced by α -linolenic acid. LTB4 can strongly attract neutrophils, eosinophils and monocytes, and increase the permeability of blood vessel wall, while the physiological activity of LT5 in this respect is only a few tenths to a few hundred percent of that of LT4. Rats were fed diets with high α -linolenic acid and high linoleic acid (safflower oil) for two generations. Glycogen was injected into abdominal cavity to aggregate neutrophils, which were stimulated to release LT substances, and then quantified. There is no big difference in the total amount of LT released, but there is a big difference in the ratio of B4 type with strong activity and B5 type with weak activity.
anti-inflammatory action
With the application of antibiotics and other antibiotics, the influence of pathogenic inflammation on human health is decreasing day by day, while some non-pathogenic and non-fatal chronic inflammations bring new threats to human health and seriously affect people's quality of life, such as rheumatism, rheumatoid arthritis, chronic rhinitis, chronic prostatitis, etc. Antipyretic and analgesic drugs, non-steroidal anti-inflammatory drugs and hormonal anti-inflammatory drugs can only play a symptomatic role in treating this kind of diseases. That is, it reduces the synthesis of various inflammatory mediators, but at the same time it has serious side effects on the body. α -linolenic acid can inhibit various inflammatory mediators and cytokines, and will not bring adverse reactions, which will bring new ideas to the treatment of this kind of diseases.
Effect of α -linolenic acid on lipid inflammatory mediators
When inflammation occurs, arachidonic acid AA on cell membrane produces a series of lipid mediators with physiological activities under the action of cyclooxygenase and lipoxygenase, mainly including prostaglandin PGE2 and tetraleukotriene LT4, which causes inflammatory reaction. EPA, a metabolite of α -linolenic acid, is a homologue of AA. By competing for the same enzyme system, PGE3 and LT5, a penta-leukotriene, can inhibit the production of PGE2 and LT4. Compared with PGE2 and LT4, PGE3 and LT5 have little effect on inflammatory activities, so α -linolenic acid has a good anti-inflammatory effect in vivo.
Effect of α -linolenic acid on inflammatory mediators (cytokines) of peptides
IL-Iβ and TNF-α are important inflammatory mediators, which can stimulate the production of collagenase, mediate the adhesion of white blood cells to endothelial cells, and activate neutrophils and macrophages to lead to inflammatory reactions. α -linolenic acid can obviously inhibit the production of cytokines, but its mechanism is not clear. After taking α -linolenic acid with 56% purity for 4 weeks, the concentration of EPA in white blood cells in the body increased, and the production of IL-Iβ and TNF-α could be inhibited by about 30%.
From the inhibition of α -linolenic acid on inflammatory mediators, it can be judged that α -linolenic acid has therapeutic effect on inflammatory diseases. Supplementing α -linolenic acid has preventive and therapeutic effects on many inflammatory diseases, such as rheumatoid arthritis, atopic dermatitis, especially prostatitis, because it is difficult for general water-soluble anti-inflammatory drugs to play their role through the lipid membrane structure surrounding the prostate, but α -linolenic acid, as a fatty acid, can easily enter the prostate through the membrane structure to play an anti-inflammatory role. Japan has developed α -linolenic acid pharmaceutical preparations to prevent asthma and allergic diseases.
Protect eyesight
As mentioned earlier, the outer segment of optic cells in the retina contains a lot of DHA. It has been reported that if DHA is deficient, vision will decrease and the recovery time of retinal reflex energy will be prolonged. Because as soon as the retina touches light, it reacts chemically, resulting in potential changes, which are then transmitted to the brain through nerves. Rats were fed with ω-6 series safflower oil and α-linolenic acid for two generations, and then given different intensities of light to change the potential, so as to compare the magnitude (amplitude) of α wave and β wave of cell membrane potential diagram to determine the retinal reflection energy. The results show that the amplitude corresponds to the content of α -linolenic acid, that is, safflower oil, control group and α -linolenic acid increase in order. Experiments with monkeys have also proved that the lack of α -linolenic acid will reduce vision.
Enhance intelligence
Docosahexaenoic acid (DHA) from α -linolenic acid is abundant in the brain and retina. At the same time, brain development is very important from fetus to lactation. By the time of weaning, most of the brain cell division has ended, and the number of nerve cells has not increased much since then, so it is very necessary to supply α -linolenic acid from pregnancy to lactation.
In addition, α -linolenic acid also has the functions of anti-cancer, anti-aging, anti-depression, prevention of senile dementia, etc., which is essential for maintaining the normal growth and development of human beings and maintaining the normal state of skin.
Ω-3 PUFA, including α -linolenic acid, has been widely used in clinic as a medicine in western countries for the prevention and treatment of cardiovascular diseases, diabetes, obesity, tumors, inflammation, depression and other diseases. Some countries also stipulate by law that α -linolenic acid must be added to certain foods, otherwise it may not be sold. It is believed that with the deepening of the research on α -linolenic acid, α -linolenic acid should have a broader application prospect. Traditional oils and fats are divided into vegetable oil and vegetable oil according to their sources, and vegetable oil is further divided into dry, semi-dry and non-drying oil according to its iodine value. According to the traditional method, oils and fats are divided into ten categories, of which six are edible vegetable oils, one is its yoke fatty acid type oil, and the other is hydroxyl fatty acid type oil. Traditionally, the fatty acids of the main vegetable oils are mainly lauric acid (coconut oil, palm kernel oil and babassu oil) and palmitic acid (palm oil). Oleic acid (olive oil, canola oil with low erucic acid, peanut oil, sunflower oil with high oleic acid, safflower oil and rattan oil), linoleic acid (medium content, corn oil, cottonseed oil, sesame oil and soybean oil), oleic acid content (high content, sunflower oil and safflower oil) and erucic acid (canola oil). Classification by fatty acid composition of oils and fats is more suitable for genetically modified oils and fats, and the fatty acid composition of such oils and fats may be changed, such as common sunflower seed oil and high oleic sunflower seed oil.