Important note: Information in this article was accurate in March 2000. The state of the art may have changed since the publication date.
Ever wonder where your energy comes from? Inside nearly all the body's cells are tiny power plants called mitochondria (Mt). To provide cells with energy, Mt "burn" a mixture of fat and sugar. This process also requires the help of other substances such as B-complex vitamins. When Mt have been damaged by drugs or when they don't have enough B-vitamins they produce less-than-normal amounts of energy.
The instructions for making new Mt are found within its DNA or genetic material. This DNA appears to be extremely sensitive to damage. As well, there is no system to repair DNA damage in mitochondria. Damaged DNA results in mistakes, or mutations, during the production of new Mt. A small number of mutations probably poses few problems. Over time, however, the level of mutations can build up and cause two basic problems:
Power failure
A decreased power supply and far less than the normal amount of Mt results in a loss of power within the cell. When cells are not able to generate the power necessary to maintain their health, they begin to malfunction and can die. All cells are affected by power shortages, but symptoms appear when energy levels fall below a certain critical level. The critical level may differ from one group of cells to another so symptoms may vary. Some symptoms include:
Drugs that have the potential to damage Mt include the currently licensed nucleoside analogues (nukes):
Other drugs that can damage Mt include:
Clearly, nukes will continue to play an important role in the anti-HIV regimens of many people. Taking "drug holidays" may be one way to give the mitochondria a rest, but this is not practical for some people. Other ways to reduce the Mt toxicity of drugs may include taking antioxidant supplements of antioxidants - vitamins C and E, alpha-lipoic acid, Co-enzyme Q10 and the amino acid L-acetylcarnitine. Our next article reports on the use of some of these supplements in people with HIV infection.
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