Carnitine is an amino acid that is used to help move fatty substances to places inside cells where they can be burnt to release energy. The parts of a cell where this energy release takes place are called mitochondria. Carnitine can also act as an antioxidant and appears to play a role in maintaining the health of nerves and protecting the liver and kidneys from the toxicity of drugs. Carnitine exists in several forms; the two most commonly used are L-carnitine and L-acetyl-carnitine.
A number of studies have found that people with HIV/AIDS (PHAs) may have less-than-normal levels of carnitine. Signs/symptoms of carnitine deficiency include the following:
- Higher-than-normal levels of triglycerides.
- Weak and/or tired muscles.
As some PHAs can develop high triglyceride (TG) levels in their blood -- whether or not they are taking anti-HIV drugs -- research teams in Montreal and Rome have found that supplements of this nutrient may be helpful for PHAs. The Montreal team recently conducted a small study to observe the effect of carnitine supplements on high TG levels in people with HIV.
Researchers enrolled 16 adult subjects who had the following profile at the start of the study:
- 1 female, 15 male.
- Average age: 43 years.
- All but one were using protease inhibitors.
- Average viral load: 2,500 copies.
- Average CD4+ count: 218 cells.
- Average TG level: 5.67 mmol/Litre (normal range 0.5 to 2).
- Average cholesterol: 5.6 mmol/Litre (normal range 2 to 5.2).
- Average glucose: 5.3 mmol/Litre (normal range 3.6 to 6.1).
Subjects received 3 grams of L-carnitine daily for an average of nine months.
One month after entering the study TG levels had decreased by an average of 39% -- a significant decrease from their pre-study levels. This decrease was maintained throughout the study.
According to the researchers, "near-normal TG levels (3 mmol/Litre or lower)" were seen in 54% of subjects after two months of L-carnitine use, and in 69% of subjects after their last lab test. There were no significant changes in cholesterol or glucose levels during the study.
No serious side effects from L-carnitine were reported and, at a dose of 3 grams/day, L-carnitine appears to be relatively safe. The results of this pilot study will be used to plan a larger more complex trial. Carnitine is sold in North America as the prescription drug Carnitor. L-carnitine and L-acetyl-carnitine are also available from some health food stores, particularly in the United States.
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- Famularo G. Alternative strategies other than growth hormone for the treatment of immune diseases. Trends in Immunology 2001;22(1):14-15.
- Bohan T.P., Helton E., McDonald I., et al. Effect of L-carnitine treatment for valproate-induced hepatotoxicity. Neurology 2001;56:1405-1409.
- Myers C.D. Carnitine; updated 1998. Available at: http://www.catie.ca/myers.nsf. Last accessed on 27 July, 2001.