Selenium: A shield for the heart. A comprehensive study of influence and mechanisms
Section 1: Selenium – key trace element for life
Selenium (SE) is an essential trace element necessary for the normal functioning of the human body. It plays a decisive role in a number of biological processes, including antioxidant protection, thyroid function, immune response and DNA synthesis. The meaning of Selena for the health of the heart is becoming more and more obvious due to the growing number of studies that demonstrate its protective properties against cardiovascular diseases.
1.1. Chemical properties and bioavailability:
Selenium exists in various forms, both organic and inorganic. Inorganic forms include selenic and selenite, and organic forms – selenometyonin and selenocysteine. Seleenomeininin is the predominant form of selenium contained in food products, especially in cereals and yeast. Selenocysteine is an amino acid that is part of selenoproteins that play a key role in various biochemical processes.
The bioavailability of selenium depends on its chemical form, as well as on the presence of other nutrients in the diet. Seleenomeininin, as a rule, has higher bioavailability than inorganic forms. The absorption of selenium can be affected by factors such as PH of the stomach, the presence of vitamins C and E, as well as the presence of heavy metals.
1.2. Sources of Selena in food:
A diverse diet, including products rich in selenium, is the best way to ensure adequate consumption of this trace element. The best food sources of Selena include:
- Brazilian nuts: One of the richest sources of Selena.
- Seafood: Tuna, sardines, salmon, shrimp.
- Meat: Beef, pork, chicken.
- Eggs: Especially egg yolks.
- Whole grain products: Brown rice, oats, barley.
- Seeds: Sunflower seeds, pumpkin seeds.
- Mushrooms: Especially the mushrooms of Shiitaka and champignons.
The content of selenium in food products can vary depending on the content of selenium in the soil where they were grown or grown. For example, Brazilian nuts grown in soils rich in selenium will contain much more selenium than those that were grown in soils with a low selenium content.
1.3. Recommended daily dose (RDA) and upper permissible level of consumption (UL):
The recommended daily dose (RDA) Selena for adults is 55 micrograms (mcg) per day. This dose is considered sufficient to meet the needs of most people. During pregnancy and breastfeeding, the need for Selena increases slightly.
The upper permissible level of consumption (UL) selenium is 400 mcg per day. Exceeding this level can lead to selenium toxicity, which can manifest itself with various symptoms, including nausea, vomiting, diarrhea, hair loss, fatigue and neurological problems. It is important to adhere to the recommended doses and avoid excessive selenium consumption, especially from food additives.
1.4. Methods for measuring the level of selenium in the body:
Determining the level of selenium in the body can be useful for assessing the status of selenium and detecting a deficiency or excess. The most common methods for measuring the level of selenium include:
- Blood test: Measurement of selenium levels in plasma or serum.
- Hair or nail analysis: Assessment of the long -term status of Selena.
- Urine analysis: Evaluation of selenium excretion with urine.
A blood test is considered the most reliable method for assessing the current status of selenium. Analysis of hair and nails can provide information about the long -term status of selenium, but external factors, such as environmental pollution, can affect the results.
Section 2: The role of selenium in the cardiovascular system
Selenium has a multifaceted effect on the cardiovascular system, due to its antioxidant, anti-inflammatory and anti-atherosclerotic properties. It plays an important role in maintaining the health of the heart and the prevention of cardiovascular diseases.
2.1. Antioxidant protection and selenoprotein:
Selenium is a key component of the antioxidant system of the body. It is part of selenoprotein, such as glutathioneperoxidase (GPX), thio -coper -lectase (TRXR) and selenoprotein P (SEPP). These selenoproteins play a decisive role in neutralizing free radicals and protecting cells from oxidative stress.
Oxidative stress occurs when the balance between the production of free radicals and antioxidant protection is disturbed. Free radicals are unstable molecules that can damage cells, proteins and DNA. Oxidative stress plays an important role in the development of many cardiovascular diseases, including atherosclerosis, coronary heart disease and heart failure.
Glutathioneperoxidase (GPX) is a family of enzymes that catalyze the reaction of the neutralization of peroxides, such as hydrogen peroxide, using glutathione as a cofactor. GPX protects cells from damage caused by peroxides, which are powerful oxidizing agents. Selehen deficiency can lead to a decrease in GPX activity and increased susceptibility to oxidative stress.
Tioredoxinreduktase (TRXR) is another important selenoprotein that is involved in the regulation of the redox balance in the cells. TRXR catalyzes the restoration of thioredoxin, protein, which plays a role in antioxidant protection, regulation of cell growth and apoptosis.
Selenoprotein P (SEPP) is the main transport protein of selenium in blood plasma. He delivers selenium to various fabrics and organs, including the heart. SEPP also has antioxidant properties and can protect cells from oxidative stress.
2.2. The influence of Selena on inflammation:
Chronic inflammation plays an important role in the development of atherosclerosis and other cardiovascular diseases. Selenium has anti-inflammatory properties and can help reduce inflammation in the cardiovascular system.
Selenium modulates the activity of various inflammatory cytokines, such as the factor of the necrosis of the alpha tumor (TNF-α) and Interleukin-6 (IL-6). TNF-α and IL-6 are pro-inflammatory cytokines that are involved in the development of atherosclerosis and other cardiovascular diseases. Selenium can reduce the production of these cytokines, thereby reducing inflammation in the cardiovascular system.
In addition, selenium can affect the function of immune cells, such as macrophages and T-lymphocytes, which play a role in the development of atherosclerosis. Selenium can modulate the activity of these cells, thereby reducing inflammation in the walls of arteries.
2.3. Selenium and endothelium function:
Endothelium is the inner layer of cells lining the blood vessels. It plays an important role in the regulation of vascular tone, preventing blood clots and controlling inflammation. Endothelium dysfunction is an early sign of atherosclerosis and is associated with an increased risk of cardiovascular disease.
Selenium can improve the function of the endothelium due to various mechanisms. Firstly, it can protect endothelial cells from oxidative stress and damage caused by free radicals. Secondly, it can increase the production of nitrogen oxide (No), which is a powerful vasodilator and plays an important role in maintaining the normal function of the endothelium. Thirdly, it can reduce inflammation in endothelial cells.
2.4. Selenium and atherosclerosis:
Atherosclerosis is a chronic disease characterized by the formation of plaques in the walls of arteries. These plaques consist of cholesterol, fats, inflammatory cells and other substances. Over time, plaques can narrow the arteries and limit blood flow, which can lead to coronary heart disease, stroke and other cardiovascular diseases.
Selenium can play a protective role in the development of atherosclerosis due to its antioxidant, anti -inflammatory and anti -atherosclerotic properties. It can protect low density lipoproteins (LDL) from oxidation, which is a key step in the development of atherosclerosis. Oxidized LDLs are more prone to capture by macrophages, which leads to the formation of foamy cells and the formation of plaques.
In addition, selenium can reduce inflammation in the walls of arteries, which can also slow down the progression of atherosclerosis. It can also affect the function of smooth muscle cells in the walls of arteries, preventing their proliferation and migration, which can also contribute to the formation of plaques.
2.5. Selenium and blood pressure:
High blood pressure (hypertension) is an important risk factor for cardiovascular diseases. Selenium can affect blood pressure, although the results of research in this area are ambiguous.
Some studies show that adequate selenium consumption can help reduce blood pressure, especially in people with selenium deficiency. The mechanisms with which selenium can reduce blood pressure, include an improvement in endothelium function, a decrease in inflammation and an increase in nitrogen oxide (NO).
However, other studies did not reveal a significant connection between Selena’s consumption and blood pressure. Additional studies are needed to confirm the effect of selenium on blood pressure and determine the optimal doses to reduce blood pressure.
2.6. Selenium and heart failure:
Heart failure is a condition in which the heart cannot effectively pump blood to meet the needs of the body. Cardiac failure can be caused by various causes, including coronary heart disease, hypertension, cardiomyopathy and other diseases.
Selenium plays an important role in the prevention and treatment of heart failure. Selehen deficiency is associated with an increased risk of developing Keshan cardiomyopathy, form of heart failure, which is endemic for some regions of China. Selena additives can improve heart function and reduce heart failure symptoms in people with selenium deficiency.
Selenium can protect the heart from damage caused by oxidative stress and inflammation, which play an important role in the development of heart failure. It can also improve the function of mitochondria, energy centers, which play an important role in maintaining the normal function of the heart.
Section 3: Clinical studies and epidemiological data
Clinical studies and epidemiological data indicate that selenium can have a positive effect on the health of the heart. However, the results of the studies are often contradictory, and additional studies are necessary to confirm these effects and determine the optimal doses of selenium for the prevention and treatment of cardiovascular diseases.
3.1. Epidemiological studies:
Epidemiological studies study the relationship between selenium consumption and the risk of cardiovascular diseases in large population groups. Some epidemiological studies have shown that people with higher selenium consumption have a lower risk of cardiovascular disease, such as coronary heart disease and stroke.
For example, one major study published in the journal American Journal of Clinical Nutritionshowed that people with the highest level of selenium in the blood had a 50% lower risk of coronary heart disease compared to people with the lowest level of selenium in the blood.
Another study published in the journal The Lancetshowed that selenium additives can reduce the risk of cardiovascular diseases in people with selenium deficiency.
However, other epidemiological studies did not reveal a significant connection between selenium consumption and the risk of cardiovascular diseases. These conflicting results can be associated with differences in research design, methods for evaluating selenium consumption, as well as the influence of other factors, such as diet and lifestyle.
3.2. Clinical research:
Clinical studies study the effect of selenium additives on markers of cardiovascular health, such as blood pressure, cholesterol, inflammatory markers and endothelial function.
Some clinical studies have shown that selenium additives can improve endothelial function, reduce blood pressure and reduce cholesterol in people with cardiovascular diseases or risk factors for cardiovascular diseases.
For example, one study published in the journal Journal of the American College of Cardiologyshowed that selenium additives improve the function of endothelium in people with coronary heart disease.
Another study published in the journal Hypertensionshowed that selenium additives reduce blood pressure in people with hypertension.
However, other clinical studies did not reveal the significant impact of selenium additives on markers of cardiovascular health. These conflicting results can be associated with differences in the doses of selenium, the duration of research, the characteristics of research participants, as well as with the influence of other factors.
3.3. Methaanalysis:
Meta -analyzes are statistical reviews that combine the results of several studies to obtain a more accurate assessment of the effect of treatment or intervention. Several meta -analyzes were carried out to assess the effect of selenium on the health of the heart.
One meta -analysis published in the journal Cochrane Database of Systematic Reviewsshowed that selenium additives can reduce the risk of cardiovascular mortality in people with selenium deficiency.
Another meta -analysis published in the journal Journal of Trace Elements in Medicine and Biologyshowed that selenium additives can improve the function of endothelium in people with cardiovascular diseases or risk factors for cardiovascular diseases.
However, some meta-analyzes did not reveal the significant effect of selenium additives on the risk of cardiovascular diseases. These conflicting results emphasize the need to conduct additional studies to confirm the effect of selenium on the health of the heart and determine the optimal doses of selenium for the prevention and treatment of cardiovascular diseases.
Section 4: Selena deficiency and its consequences for the heart
Selena deficiency can have serious consequences for the health of the heart, increasing the risk of cardiomyopathy, heart failure and other cardiovascular diseases.
4.1. Causes of selenium deficiency:
Selena deficiency can be caused by various factors, including:
- Low selenium content in the soil: In some regions of the world, such as some areas of China and Russia, the soil is poor selenium, which leads to a low content of selenium in food products grown in these regions.
- Insufficient consumption of selenium with food: People who do not consume enough products rich in selenium, such as seafood, meat, eggs and whole grain products, can be at risk of selenium deficiency.
- Selena absorption disorders: Some diseases, such as Crohn’s disease and cystic fibrosis, may disrupt the absorption of selenium from the intestines.
- Dialysis: People who are on dialysis can lose selenium during the procedure.
- HIV infection: HIV infection can lead to selenium deficiency due to the increased need for selenium and selenium absorption disorders.
4.2. Symptoms of selenium deficiency:
Symptoms of selenium deficiency can be non -specific and include:
- Fatigue:
- Muscle weakness:
- Joint pain:
- Hair loss:
- Reduced immunity:
- Slow down growth:
- Increased risk of cardiovascular disease:
4.3. Cardiomyopathy Kesana:
Keshan cardiomyopathy is a form of heart failure, which is endemic for some regions of China, where the soil is poor selenium. Keshan cardiomyopathy is characterized by an increase in the heart, a violation of its function and an increased risk of sudden heart death.
Selenium deficiency is considered the main cause of Keshan cardiomyopathy. Selena additives can prevent the development of Keshan cardiomyopathy and improve the function of the heart in people with this disease.
4.4. Other cardiovascular consequences of selenium deficiency:
Selena deficiency can also increase the risk of other cardiovascular diseases, such as coronary heart disease, heart failure and stroke. It can also aggravate the course of these diseases.
Selenium deficiency can lead to increased oxidative stress and inflammation in the cardiovascular system, which can contribute to the development and progression of cardiovascular diseases.
Section 5: Selena toxicity and precaution
Although selenium is necessary for health, excessive selenium consumption can be toxic. It is important to adhere to the recommended doses of selenium and avoid excessive selenium consumption, especially from food additives.
5.1. Symptoms of selenium toxicity (selenosis):
Symptoms of selenium toxicity (selenosis) may include:
- Nausea:
- Vomiting:
- Diarrhea:
- Hair loss:
- Nail defeat:
- Fatigue:
- Irritability:
- Neurological problems:
- The smell of garlic from the mouth:
In severe cases, the toxicity of selenium can lead to liver failure, renal failure and even death.
5.2. Selena toxic risk factors:
The risk factors of selenium toxicity include:
- Excessive consumption of selenium additives:
- Professional influence of Selena:
- Some diseases:
5.3. Recommendations for the safe consumption of Selena:
To avoid selenium toxicity, it is recommended to adhere to the following recommendations:
- Do not exceed the upper permissible level of consumption (UL) selenium, which is 400 mcg per day for adults.
- Get selenium mainly from food products, and not from food additives.
- If you take selenium supplements, consult your doctor to determine the correct dose.
- Do not take selenium supplements if you have no selenium deficiency.
Section 6: Selenium and interaction with other nutrients
Selenium can interact with other nutrients, affecting their absorption and effectiveness.
6.1. Selenium and Vitamin E:
Selenium and vitamin E are two important antioxidants that work synergistic to protect cells from oxidative stress. Selenium is part of glutathioneperoxidase (GPX), and vitamin E is a fat -soluble antioxidant that protects lipids from oxidation.
The joint consumption of selenium and vitamin E can increase their antioxidant protection and reduce the risk of developing cardiovascular diseases.
6.2. Selenium and iodine:
Selenium plays an important role in the function of the thyroid gland, which is necessary for the production of thyroid hormones. The thyroid hormones are necessary to regulate metabolism and cardiovascular function.
Selenium is involved in the transformation of the thyroid hormone T4 into T3, which is a more active form of the thyroid hormone. Selena deficiency can disrupt the function of the thyroid gland and lead to hypothyroidism, which can increase the risk of cardiovascular diseases.
Adequate consumption of selenium and iodine is necessary to maintain the normal function of the thyroid gland and heart health.
6.3. Selenium and Zinc:
Selenium and zinc are two important trace elements that play the role in the immune function. The deficiency of selenium and zinc can weaken the immune system and increase the risk of infections.
Selenium and zinc also have antioxidant properties and can protect cells from oxidative stress. Adequate consumption of selenium and zinc is necessary to maintain normal immune function and protection against cardiovascular diseases.
Section 7: Research Prospects and future areas
Despite the fact that it is already known about the role of Selena in the health of the heart, there are questions that require further study.
7.1. The optimal doses of selenium for the prevention and treatment of cardiovascular diseases:
Additional studies are needed to determine the optimal doses of selenium for the prevention and treatment of cardiovascular diseases. The results of existing studies are contradictory, and the optimal doses of selenium can vary depending on the age, gender, state of health and other factors.
7.2. The influence of various forms of selenium on the health of the heart:
Selenium exists in various forms, both organic and inorganic. Additional studies are needed to study the influence of various forms of selenium on the health of the heart. Some studies show that the organic forms of selenium, such as selenometyine, can be more bio -accessible and effective than the inorganic forms of Selena.
7.3. The role of selenium in the prevention and treatment of specific cardiovascular diseases:
Additional studies are needed to study the role of selenium in the prevention and treatment of specific cardiovascular diseases, such as coronary heart disease, heart failure, stroke and arrhythmias.
7.4. The interaction of selenium with other nutrients in the context of the heart health:
Additional studies are needed to study the interaction of selenium with other nutrients, such as vitamins E and C, iodine and zinc, in the context of heart health. Understanding these interactions can help develop more effective strategies for the prevention and treatment of cardiovascular diseases.
7.5. Genomic and proteomic studies of the role of selenium in the cardiovascular system:
Genomic and proteomic studies can help identify genes and proteins, which are affected by selenium in the cardiovascular system. This can lead to a better understanding of the mechanisms by which selenium affects the health of the heart, and help develop new strategies for the prevention and treatment of cardiovascular diseases.
Section 8: Conclusion (lowered in accordance with the instructions)
(In accordance with the instructions, there is no conclusion).