Purines play several important roles in the body. They help make DNA and RNA, which are the blueprints of cells, and help to construct protein. They help carry energy in the form adenosine triphosphate, or ATP, one of the primary energy currencies of the cell. Because purines have multiple important roles in the body, interfering with their functions at different points can cause various diseases. Most purine diseases are a problem of purine metabolism.
Gout
As noted by "Harrison's Principles of Internal Medicine" by Dr. Anthony Fauci, gout is a type of painful arthritis in which the joints, often the big toe, become extremely tender, swollen and red. It is caused by crystals of uric acid depositing in the joints and leading to inflammation. Purines are broken down into uric acid. Excessive amounts of purines in some people will cause the development of gout. The purines in meats and fish increase the chances of a gout attack in those prone to the condition. Treatment involves lifestyle changes such as diet and exercise and medical management.
Diseases of Purine Breakdown
In the disease called adenosine deaminase deficiency, the body has trouble breaking down the purine adenosine, which builds up in the cells and is converted to other similar chemicals. Excessive amounts of these chemicals interfere with DNA synthesis. Cells of the immune system are particularly sensitive to this disease, and it can lead to immune compromise and severe infections. Treatment involves enzyme replacement and bone marrow transplantation.
Diseases of Purine Recycling
Purines are partially broken down or used, then some of them are completely broken down to uric acid and excreted, while others are recycled to be used again. In Lesch-Nyhan syndrome, the process of recycling is interrupted by deficiency of the enzyme hypoxanthine-guanine phosphoribosyl transferase. According to "Pathologic Basis of Disease," by Dr. Vinay Kumar, people affected by the disease acquire gout, intellectual disability, involuntary movements, muscle spasms and self-mutilation. There is no treatment for this disorder yet.
Diseases of Purine Synthesis
Phosphoribosylpyrophosphate synthetase superactivity, or PRS superactivity, causes the overproduction of purines. It can exist as a severe or milder type. The enzyme involved produces purine chemicals that cause gout, kidney stones, hearing loss, weak muscles, nerve damage, developmental delays and trouble walking. Treatment involves a low purine diet and the drug allopurinol.
References
- "Harrison's Principles of Internal Medicine (17th edition)"; Dr. Anthony Fauci et al; 2008
- "Robbins and Cotran Pathologic Basis of Disease (eighth edition)"; Vinay Kumar et al; 2009
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