Cushing's Hit the Mainstream News Services!

[~MaryO~]

http://story.news.yahoo.com/news?tm....hing_dc

 

Health - Reuters

 

Diabetes Drugs May Help Cushing's Syndrome

By Keith Mulvihill

 

NEW YORK (Reuters Health) - A new study in mice is helping researchers zero in on a potential treatment for Cushing's syndrome, a hormone disorder that can be caused by a tumor in the brain's pituitary gland.

 

While such tumors can be removed surgically, this may not always cure the disease and there are no drugs suitable to treat the condition. The new study suggests that commonly used diabetes drugs may help such patients, according to a report in the November issue of the journal Nature Medicine.

 

Cushing's syndrome results from high levels of the hormone cortisol, and can cause fat accumulation in the upper body and face, and thinning of the arms and legs. Patients can experience high blood pressure and high blood sugar, along with depression, fatigue, irritability and weakened bones.

 

Cortisol levels rise when another hormone, called adrenocorticotropic hormone (ACTH), is overproduced by the brain's pituitary gland. ACTH stimulates the adrenal glands, which sit on top of the kidneys, to produce the cortisol, explained lead author Dr. Anthony P. Heaney of the Cedars-Sinai Medical Center in Los Angeles, California during an interview with Reuters Health.

 

Cushing's syndrome can be caused by a tumor of the pituitary gland, a tumor of the adrenal gland or by long-term use of drugs, called corticosteroids, commonly used to treat illnesses, such as rheumatoid arthritis and asthma.

 

In the current study, Heaney and colleagues found that a protein called PPAR-gamma, which is found on pituitary gland tumor cells, appears to be linked to overproduction of ACTH.

 

The researchers injected mice with ACTH-secreting pituitary tumor cells and then treated them with commonly used diabetes drugs, rosiglitazone (Avandia) and troglitazone, or an inactive placebo. Such drugs are known to inhibit PPAR-gamma, which also plays a role in sugar metabolism. Troglitazone (Rezulin) was withdrawn from the US market in 2000 after it was linked to liver damage and deaths in some patients.

 

The investigators found that production of ACTH, as well as the chemical equivalent of human cortisol in mice, dropped substantially.

 

"We saw pretty dramatic reduction in ACTH and cortisol-like hormone in the mice that got either of the drugs," Heaney told Reuters Health. "There was an 85% reduction in ACTH and a corresponding 96% reduction in their cortisol-like hormone."

 

In addition, the drugs caused the tumor cells to die and the overall size of the tumors to shrink, Heaney explained.

 

"Since we know that PPAR-gamma plays a role in the pituitary tumors that cause Cushing's syndrome, we may be able to treat the illness effectively with (the diabetes drugs)," he added.

 

The study was funded by the Doris Factor Molecular Endocrinology Laboratory, the Annenberg Foundation, and a National Institutes of Health grant.

 

SOURCE: Nature Medicine 2002;8:1281-1287