Mitochondria are often called the “power plants” of human cells

Mitochondria are often called the “power plants” of human cells. All cells contain these microscopic structures, which produce energy for the cell to do its work and stay healthy. Mitochondria convert fats and carbohydrates into a molecule called ATP, the basic fuel for cells. Some cells, like nerve, heart and muscle cells, need a lot of ATP, so they have a lot of mitochondria.

One of the most troublesome toxicities of anti-HIV drugs is that they can damage mitochondria. Some anti-HIV drugs damage the DNA so that the cell can’t produce new mitochondria. When cells get low on mitochondria, they can’t make enough energy to function properly. This condition is called mitochondrial toxicity. It wreaks havoc throughout the body and is thought to contribute to nerve damage (neuropathy), muscle damage (myopathy), heart muscle damage (cardiomyopathy), fat wasting (lipoatrophy) and other health problems. Two anti-HIV drugs associated with the highest risk of mitochondrial toxicity—d4T (stavudine, Zerit) and ddI (didanosine)—are used much less frequently now that we have newer, safer drugs that are less likely to cause this effect.

People experiencing mitochondrial toxicity often have elevated levels of lactate (lactic acid) in the blood. High lactate levels can cause nausea, headaches and fatigue and can make you feel full on a small amount of food (early satiety). Very high lactate levels, called lactic acidosis, can be fatal. If lactic acidosis has occurred or is suspected by your doctor, HAART must be stopped temporarily. Once the acidosis subsides, you may restart HAART with a different combination of anti-HIV drugs.

There are no specific nutrition guidelines for treating mitochondrial toxicity, but some small studies have shown a benefit from B vitamins and L-carnitine supplementation. As well, treatment options for children born with defective mitochondria may provide some guidance. In these children, experts often recommend supplementation with all the cofactors that help the mitochondria function properly (see below). Although there is no scientific evidence that this strategy works for mitochondrial toxicity in HIV, it may offer benefits in terms of feeling better and being able to stay on medications.