Some Obesity Linked To Virus

BOSTON, Aug. 23 -- Obesity may be caused -- at least in some cases -- by a virus, researchers said here.

Adenovirus-36, one of a family of about 50 common viruses, appears to cause stem cells in fat tissue to develop into adipocytes rather than other forms of cell, according to Nikhil Dhurandhar, Ph.D., of Louisiana State University in Baton Rouge, told attendees at the American Chemical Society meeting.

What's more, the new fat cells accumulate more fat than similar cells that develop from uninfected stem cells, said Dr. Dhurandhar, the study's senior author.

"Obesity is multi-factorial," Dr. Dhurandhar said. "Infections may be one of the causes."

In the long run, he said, the implication for clinicians is that therapy based on a specific cause of obesity may be more successful than the "blanket therapy" now employed.

Dr. Dhurandhar said the finding opens up the possibility of preventing at least some obesity by targeting the virus with a vaccine. But, he added, fat people shouldn't take the finding to mean that they can blame their condition on a virus.

"This only explains how you got there," he said. "It doesn't absolve you of the responsibility to take care of yourself."

The researchers took adult stem cells from fatty tissue from a broad cross-section of patients who had undergone liposuction.

Half of the stem cells were exposed to adenovirus-36 and half were not, according to Magdalena Pasarica, M.D., Ph.D., also of the Pennington Biomedical Research Center, who presented the study.

After about a week in culture, most of the infected stem cells had developed into adipocytes, but only a few of the uninfected cells did, Dr. Pasarica said in a statement.

What's more, the infected adipocytes accumulated 2.5 times more fat on average than fat cells that developed from non-infected stem cells, Dr. Dhurandhar said. The difference was statistically significant at P

The difference was significant at P