Cysteine

2024 Author: Jasmine Walkman | [email protected]. Last modified: 2023-12-16 08:29

Cysteine is a sulfur-containing amino acid that can be obtained naturally through food, it can also be produced by the body, from the amino acid methionine. In the production of cysteine, methionine is converted to S-adenosyl methionine, which is then converted to homocysteine. Homocysteine reacts with serine to form cysteine.

Cysteine plays a key role in maintaining glutathione in the human body. Its formula is C3H7NO2S and it is extremely important for the proper functioning of the muscular system. An interesting fact is that cysteine is part of the composition of insulin, with which it has the ability to be converted into pure glucose if necessary. Thus, in reality, this substance can saturate the body with more energy for the various activities we perform daily. That is why this supplement is important for people who train a lot and generally lead a very active lifestyle.

Cysteine functions

Antioxidant activity - as a main component of glutathione, cysteine has many important physiological functions. Glutathione, formed from cysteine, glutamic acid and glycine, is found in all human tissues, with its highest concentrations in the liver and eyes. Glutathione is a powerful antioxidant, protecting adipose tissue from the harmful effects of free radicals.

Detoxification - glutathione also plays a vital role in liver detoxification. Glutathione also carries important nutrients to lymphocytes and phagocytes - cells important for the immune system.

Helps eliminate mucus - Cysteine also has the ability to break down proteins contained in mucus that damage the lungs. As a result, it can be useful in treating bronchitis and other respiratory problems.

Cysteine deficiency

Cysteine deficiency can be seen in vegetarians who eat plant foods low in methionine and cysteine. However, a medical condition directly caused by cysteine deficiency is not known.

Consumption of foods with cysteine or methionine is unlikely to cause toxic symptoms. However, cysteine is a brain excitoxin that can cause damage to the cells in the brain of susceptible individuals. Such people do not have a proper amino acid metabolism and as a result may be at risk of some neurodegenerative diseases, including multiple sclerosis, Alzheimer's disease and others.

Cysteine deficiency adversely affects the body and in particular the condition of hair, nails and skin. This can even lead to depression. No less important is the fact that the lack of enough cysteine in the body can become a provoking factor for a number of pathologies of the heart system, digestive problems, memory impairment or weakened immunity.

Cysteine overdose

High doses of oral N-acetyl-cysteine, such as those given to patients with acetaminophen toxicity, may cause nausea, vomiting and diarrhea. Intravenous administration of N-acetyl cysteine can cause allergic reactions, and in a small percentage of people it is characterized by reddening of the skin, drop in blood pressure, irregular heartbeat and respiratory distress. Accidental overdose of intravenous N-acetyl-cysteine could be fatal.

The combination of nitroglycerin and N-acetyl-cysteine can cause severe headaches. Cysteine helps in the rapid metabolism of acetaminophen so as to prevent liver damage. N-acetyl cysteine also protects against heart damage caused by certain drugs during chemotherapy and increases the effectiveness of interferon in the treatment of hepatitis C.

There are people who show individual intolerance to this supplement and this leads to swelling of the throat and face, skin rash and difficulty breathing. In this case, it is vital to seek medical attention immediately.

Allergic reaction to cysteine due to the fact that the body takes it as a toxin and thus fights it, producing huge doses of homocysteine. That is why it is especially important to consider how your body tolerates each supplement, which also applies to the foods you eat.

Required daily norm of cysteine

If you are taking this amino acid cysteine in the form of supplements, the daily norm of the package is always indicated. It is important to adhere to these recommendations, as taking higher doses of cysteine has its side effects on the body. When taking this amino acid, you should also drink enough water. Experts believe that daily norm is equal to 2500-3000 mg. A dose above 7000 mg has the opposite effect on the body, namely it is toxic and can cause quite unpleasant health side effects.

Cysteine synthesis

Cysteine in the human body is obtained with the help of another important amino acid, namely the so-called methionine. The very process of obtaining and in particular the conversion of methionine to cysteine is quite complex. The presence of certain vitamins and enzymes involved in this process is very important. This leads to confusion of the body's system, namely the lack of any important components involved in cysteine synthesis.

In some diseases, a "systemic disorder" can also occur in the body and as a result, the conversion of methionine to cysteine can also be difficult. Diseases are of great importance for the synthesis of amino acids. This is especially true for pathologies of the liver and metabolic disorders.

An interesting feature is that this synthesis does not occur in the body of newborns. The reason for this is that babies receive all the necessary substances from the mother's breast milk, including cysteine.

Benefits of cysteine

Cysteine may play a role in the prevention and / or treatment of the following diseases: acute respiratory distress syndrome, asthma, cancer, cataracts, hair loss, heart disease, severe metal toxicity, AIDS, liver disease, psoriasis, rheumatoid arthritis and viral infections.

However, its benefits are far from over. In 2008, a very interesting study was done on rats, which showed a significant improvement in the condition of animals with diabetes. For example, after taking cysteine, the level of blood sugar in their body is significantly reduced and the sensitivity of animals to insulin has increased. Additionally, cysteine helps to inhibit inflammation of blood vessels.

In 2008, other important evidence was made about the benefits of this substance on the intestines and in particular in their inflammation. Thus, it has been proven that the amino acid has an excellent positive effect in colitis. Pigs participated in this experiment.

Along with all this, it prevents the production of free radicals. This was proven in a 7-day experiment involving 10 men who showed an increase in the body's antioxidant capacity, as well as a decrease in the formation of free radicals.

In alternative medicine cysteine is used as a natural remedy for:

- angina;

- cardiovascular diseases;

- chronic bronchitis;

- diabetes;

- flu;

- inflammation;

- intestinal diseases;

- osteoarthritis.

Who needs cysteine the most?

Everyone needs this amino acid, but for some people it is even more important. This is especially true for those of you who lead a very active lifestyle, train actively, under severe stress and in people who have weakened immunity. They have a special need for food or cysteine supplements.

Proper nutrition will help to optimize bodily functions and increase resistance to disease. Therefore, it is especially important to eat foods that are rich in this amino acid in people who have AIDS, have heart disease or respiratory problems.

Action of cysteine and other substances

Today, this area is much better studied, namely how this amino acid can affect the body in combination with other substances. The supplement has a negative interaction with some medications. For example, this component blocks the action of drugs in angina. The supplement is not recommended for pregnant and breastfeeding women or for taking drugs that suppress the immune system.

The amino acid in industry

Cysteine is used active in the food industry as a supplement E920. Thus, it is not only meaningless for the body, but is even believed that in the form of a dietary supplement causes kidney and cardiovascular disease.

Cysteine supplements can be of both natural and synthetic origin. The production process of the former is much cheaper, and on the other hand, the latter are the result of a number of complex processes in the chemical industry. Various raw materials, such as feathers or wool, can be used in the production of natural amino acids. As you know, they are quite rich in keratin, which is so important for the body, which contains cysteine. As a result of prolonged manipulations, the product of its decomposition is extracted from the raw material in the form of this amino acid.

Sources of cysteine

Cysteine can be obtained through a variety of foods, including poultry, yogurt, egg yolk, red peppers, garlic, onions, broccoli, Brussels sprouts, oats and wheat germ. Rich in cysteine are eggs, cod, pork kidneys and liver, caviar, raw sunflower seeds.

Cysteine, along with other sulfur-containing amino acids such as methionine, is recommended for use in all individuals over the age of 1 year. 25 milligrams of cysteine plus methionine (combined) for every 1 gram of dietary protein.

See also all about the amino acid cystine.