Kynurenine Tryptophan Cycle in Addiction

The immune system is an important part of normal body functioning. It is constantly modulating a balance between tolerance to non-harmful antigens and responsiveness to some pathogens. The process that facilitates tolerance is not known. However, recent studies show that this tolerance is due to tryptophan catabolism via the kynurenine metabolic pathway. The breakdown of tryptophan requires several enzymes which. These enzymes are found in various cells which includes those of the immune system.

Some of these enzymes involved in the breakdown of tryptophan produced through activation of the immune system. This process involves among others limitation of enzymes that are present in the dendritic cells and macrophages, 3-dioxygenase and indoleamine 2. Recent studies have shown that inhibition of these enzymes can result in the body rejecting allogeneic fetuses. This means that breakdown of tryptophan is necessary in immune tolerance aspects.

Some theories have been invented to try and explain how catabolism of tryptophan facilitates tolerance to drugs like alcohol. One such theory holds it that breakdown of tryptophan ends up suppressing proliferation of T cells by greatly reducing the supply of this amino acid that is critical in body processes. The other theory states that the down streaming of the metabolites involved in catabolism of tryptophan act as suppressors of some immune cells mainly through mechanisms of pro-apoptotic processes.

Kynurenine Tryptophan Cycle

What is tryptophan?

It is an amino acid that is required by all processes of the body for the synthesis of proteins and other body metabolic functions. Tryptophan is synthesized mainly from molecules like phosphoenolpyruvate that are present in bacteria, plants and fungi. Such organisms activate the tryptophan throughout the food chain. Animals are incapable of synthesizing this amino acid and because of this it must be taken in the diet in form of proteins which are then broken down into the respective amino acids in the digestive tract. The tryptophan that results from diet is deposited in the liver via the hepatic portal system. The protein that is not broken down in the liver enters into any of the two metabolic processes.

Because animals are incapable of synthesizing tryptophan, they must take it in the form of proteins, which are then hydrolyzed into the constituent amino acids in the digestive system. Dietary tryptophan is delivered to the liver through the hepatic portal system, and that portion which is not used for protein synthesis in the liver can then follow one of two basic metabolic fates.

In the first place, the protein that does not undergo synthesis can enter into the blood stream to later be used for synthesis of proteins and other cell functions in the body. Secondly, it can undergo degradation in the liver via a number of steps of metabolism which is basically referred to as the kynurenine pathway. Besides being a building block for proteins in the body, tryptophan also acts as the only source of substrate used for the production of important molecules in the body. Tryptophan is used in the gut and nervous system for serotonin synthesis and on the other hand pineal gland is useful in melatonin synthesis. In case the content of niacin in the body is not enough to carry out metabolic processes, tryptophan come in to facilitate cellular cofactor synthesis and nicotinamide adenine dinucleotide (NAD +) synthesis. NAD + synthesis as research shows take place mostly in the liver.

The kynurenine pathway

The kynurenine pathway results from proteins that are not synthesized in the liver. The enzymatic reactions take place proceeding from tryptophan. The main intermediates of the metabolic system include quinolinate, 3-hydroxyanthranilate and kynurenine. A catabolic reaction is completed in the liver and this result in the total oxidation of the amino acid tryptophan and in the process carbon dioxide and adenosine triphosphate are produced.

Tryptophan metabolism and addiction

The three stages that take place in the kynurenine pathway include an intial stage that involves tryptophan being broken down into kynurenine. The second stage starts from the produced kynurenine all the way to production of quinolinate. The final stage of the process involves enzymes that translate into total oxidation. The other processes that occurs within the three major processes picolinate production, kynuretic acid synthesis and synthesis of NAD +.

Most cells in the body have some of the enzymes that are involved in the kynurenine pathway. However, only hepatocytes have been shown to contain each and every enzyme that is used in every stage of the kynurenine pathway. Since the liver is the only tissue in the body that contains all thes enzymes of the pathway, the liver then acts as the major site in which NAD + is synthesized from tryptophan. Diet and intake of certain substances like alcohol can affect the flow of metabolisms in the kynurenine pathway. For more information about this topic visit www.awaremednetwork.com. At AwareMed you will also find other health and awareness tips that will benefit you.

Kynurenine Tryptophan Cycle in Addiction

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Low Testosterone and Anxiety

January 5, 2015

Low Testosterone Causes Anxiety and Depression

Low testosterone Testosterone is a very important hormone in the body. Of all the androgens it is the most dominant and is charged with very many responsibilities. Many people still think that testosterone has only one function which is to ensure a good sexual performance. No testosterone has far more functions that together make your life what it ought to be. So, to the many people who think that deficiency in testosterone hormone can only affect your sexual life, it’s time to think again. The reality is that this hormone has very many roles beyond ensuring a healthy sex life. Apart from production of sperms, the testosterone hormone is also crucial in production of red blood cells. This hormone also helps in distribution of fats in the body parts, increasing muscle mass, improving bone mineral density and even regulation of moods in a person. A major symptom of those suffering flooring testosterone levels is low moods. It is common to find men who are suffering from hypogonadism in bad moods as any decline in this hormone does much to dampen moods of an individual. It is also this hormone that gives men the physique of man- masculinity.

Anxiety and depression linked to Low T

Several studies have also found out that high levels of testosterone in a person reduce their risks of developing anxiety and depression. Many researchers have proved that many men who suffer from anxiety and depression are of low testosterone levels and therefore testosterone replacement therapy may help them to fight anxiety and depression. After testosterone replacement therapy most anxiety and depression patients break free from the bonds of anxiety and depression. Anxiety and depression are major problems that men deal with today. The number of men held victims by these two conditions increase rapidly with low testosterone levels being a major contributor to these conditions.

Currently, in the United States alone, the numbers of men who have fallen victims to anxiety and depression have doubled the number of women suffering from the same. This can be attributed to the many roles that this hormone plays in men. Scientists have proved that maintaining an optimum level of testosterone hormone is an effective way of fighting anxiety and depression. In a study that was published in 2005 in the Journal of Clinical Psychiatry, a team of researchers from the US Department of Veterans Affairs examined the connection between low testosterone levels and future depression risks in more than 700 men who were at least 50 years old. The report concluded that men aged below 50 years with low testosterone level were more likely to become depressed than men within the same age but have optimum level of testosterone hormone. The finding from this study is enough to tell prove the link between low testosterone levels to anxiety and depression.

However this is not the only study that has established the connection between testosterone and depression. Another study that was published in 2003 in the American Journal of Psychiatry also examined the connection between these two phenomena. The research done by Harvard University worked with 56 men who had developed major anxiety and depression but had failed to respond to antidepressant treatments. The researchers found that 40 percent of the men had low testosterone levels. It can therefore be concluded that going for testosterone replacement therapy can help an individual fight against anxiety and depression and restore good health in men.

Can Testosterone replacement Therapy really help?

Testosterone replacement therapy is one of the most common solutions to anxiety and depression induced by low testosterone levels. It only makes sense that when a person has low levels of testosterone then he ought to have the levels of testosterone in his body supplemented so that the normal levels can be restored.

What does it involve?

Testosterone replacement therapy involves supplementation of testosterone in the body. This can be done in form of injections, pellets, patches or gel in order to treat conditions in which the testes do not produce enough testosterone. It is also available in IV forms. Just like the estrogen replacement therapy in women, this ought to be done by an expert as the dosage is important for better results and to mitigate on the side effects. This therefore cannot be done without the help of an expert. This therapy has been found to be effective in fighting hypogonadism and all other major symptoms associated with low testosterone levels. It is also good as it improves energy levels, perfect body mass, sex functions and muscle strength among other benefits.

Testosterone replacement therapy has been used for a long time in treatment of men with erectile problems which are also a major cause of anxiety among men. Hypogonadism is a problem that most men go through and seek treatment from every day. however many patients seem to concentrate on getting their sexual energy back but are blind to other conditions that might be suffered as a result of hypogonadism. Men who suffer hypogonadism are not strangers to anxiety and depression and therefore emphasis should be placed more on the debilitating effects of low testosterone levels other than a fall in sexual drive and performance in men as is mostly the case. The use of testosterone replacement therapy in hypogonadism is not news, however some people are still not aware of the link between anxiety and depression and low testosterone levels.

Finally

Dr. Dalal Akoury of AWAREmed Health and Wellness Center has dedicated her life to helping patients restore their lives by use of integrative medicine. She also holds many conferences in which she offers training on how integrative medicine can be used to fight addiction among other conditions. Call her on (843) 213-1480 for help.