Retinaldehyde: Vitamin A Derivative, May Protect Against Diabetes

Filed in archive Information , Notable , Research on June 17, 2007

Retinaldehyde - a derivative of Vitamin A - has long been known for only one job in mammals: as phototransducer in the eye.

Now, Harvard Medical School (HMS) researcher has found a newly-discovered role for this retinoid: it limits fat cell development.

HMS researchers Ouliana Ziouzenkova, Gabriela Orasanu, Jorge Plutzky, and Molly Sharlach, with colleagues, showed that the retinoid helps reduce fat deposits in mice and protects them against type 2 diabetes.

Exactly how retinaldehyde works is not clear, but it seems to be related to PPARs, retinoid receptors, and general metabolism. The researchers found that Raldh-negative animals have higher metabolic rates and elevated body temperature compared to control animals, which helps explain why they do not gain weight.

The retinoid also binds to PPAR-gamma, albeit weakly, and attenuates increases in adiponectin and adipogenesis driven by the PPAR-gamma agonist rosiglitazone.

Plutzky and colleagues also found that retinaldehyde has both retinoid X receptor-dependent and -independent effects on lipid cell precursors and it could also bind to retinoid binding protein 4, a retinoid carrier protein that HMS researcher Barbara Kahn has linked to diabetes.

This finding - reported online May 27 in Nature Medicine - could dramatically change how researchers view obesity and the retinoid itself and hopefully will lead to a potentially more efficient type 2 diabetes drug in the future.

Find more details from Harvard Medical School.