diabetes drug found to inhibit cognitive impairment due to radiation therapy to brain

[Lani]

Diabetes Drug May Inhibit Radiotherapy-Induced Cognitive Dysfunction

NEW YORK (Reuters Health) Jan 22 - Treatment with the diabetes drug pioglitazone, a PPAR-gamma agonist, may help prevent the cognitive impairment that often accompanies radiotherapy to the brain, findings from an animal study suggest.

"These findings offer the promise of improving the quality of life of these patients," Dr. Mike E. Robbins, from Wake Forest University School of Medicine in Winston-Salem, North Carolina, said in a statement. "The drug is already prescribed for diabetes and we know the doses that patients can safely take."

Up to one half of brain tumor patients who receive radiotherapy will develop progressive cognitive impairment, according to the report in the International Journal of Radiation Oncology, Biology, and Physics for January. Chronic inflammation is thought to play a key role in this pathogenic process and recent reports have suggested that PPAR-gamma agonists may have a beneficial effect in this regard.

The present study involved young adult rats that received sham or real whole brain irradiation with or without pioglitazone before, during, and after treatment. Object recognition testing was used to assess cognitive function 1 year after completion of radiotherapy.

Compared with rats that received sham irradiation, irradiated rats that did not receive pioglitazone displayed cognitive impairment. By contrast, no drop in cognitive function was observed in irradiated animals treated with pioglitazone. Further testing showed no advantage for continuing the drug for 54 weeks after irradiation compared with just 4 weeks.

"Translating these findings to the clinic offers the promise of not only improving the quality of life for long-term brain tumor survivors, but also increasing their therapeutic window," the authors conclude.

Int J Radiat Oncol Biol Phys 2007;67:6-9.