A nontoxic dietary supplement is giving new hope to some HIV-positive people whose immune systems have been ravaged by the virus, researchers reported Saturday. The supplement, known as N-acetylcysteine or NAC and available in any health food store, restores the body's stores of an antioxidant molecule called glutathione, the new research showed.
And among the 200-plus patients studied, the more glutathione molecules that HIV-infected patients carried in their immune system, the longer the patients were likely to survive.
The new findings also suggest that Tylenol can be deadly for AIDS patients as the popular painkiller can deplete the bodys glutathione stores.
Glutathione was found to be an even better predictor of survival and sickness among HIV-infected people than the traditional measure of predicting disease progression; the CD4 count, according to study authors Leonore and Leonard Herzenberg, genetics professors at Stanford University School of Medicine in Stanford, Calif.
It's been known since 1989 that people with HIV have CD4 cells deficient in glutathione, Leonard Herzenberg said. Now we know that glutathione levels matter to patient survival.
Restoring glutathione levels is particularly important for the survival of people whose CD4 counts are less than 200, he said. The disease-fighting soldiers of the body's immune system, CD4 cells are attacked by the AIDS virus and their number typically declines as HIV progresses. An infected patient with a CD4 count of less than 200 cells per microliter of blood is considered to have AIDS even in the absence of other symptoms, while a healthy person has a CD4 count of about 1000.
"Total CD4 counts don't reliably predict how long an individual patient is likely to live or how rapidly the person's disease will progress,"; Leonore Herzenberg said. "Some patients with low CD4 counts unexpectedly survive a very long time,"; she said, and glutathione may explain why.
So what is this powerful molecule and what does it do?
A natural antioxidant found in protein-rich foods such as meat, glutathione plays a role in body activities ranging from cell integrity to mopping up oxidants and other toxic molecules.
The researchers don't know for sure why it works, but it seems logical that it helps rebuild the immune system or helps a damaged immune system work better, Leonard Herzenberg said.
The husband-and-wife team studied 204 patients, all infected with the AIDS virus but with no outward signs of illness.
Over the next three years, patients who maintained normal glutathione levels; "even if their CD4 counts were low"; tended to outlive those with low glutathione levels.
The study included 97 patients with CD4 counts below 200. Most of these patients also had low levels of glutathione and died within three years. But among the 28 patients who started the study with low CD4 counts but maintained normal glutathione levels, 23 or about 80 percent; survived. "And in second study in which NAC was given to about 25 HIV-infected patients with such low glutathione levels that the doctors thought they would die, the patients survived," Lenore Herzenberg said.
"Daily NAC tablets boosted glutathione to healthy levels," she said. John Jones, publisher of the San Francisco-based newsletter AIDS Treatment News, said "NAC is a safe, cheap supplement; that AIDS patients may want to consider as a supplement to conventional therapies such as protease inhibitors." In addition to health food stores, NAC can be purchased through AIDS buying clubs, he added.