Investigadores de la UCLA clarifican la función de la molécula transportadora de glucosaContributed by: AdminStaff1 · Views: 2,169
Contributed by: AdminStaff1 · July 04, 2008 @ 05:09 PM MDT · Views: 2,169
UCLA researchers clarify function of glucose transport molecule Findings may lead to improved treatments for diabetes, obesityBy Elaine Schmidt
Researchers at the David Geffen School of Medicine at UCLA have solved the structure of a class of proteins known as sodium glucose co-transporters (SGLTs), which pump glucose into cells. These transport proteins are used in the treatment of chronic diarrhea through oral rehydration therapy, saving the lives of millions of children each year. The solution of the SGLT structure will accelerate the development of new drugs designed to treat patients with diabetes and cancer.
3-D image of sodium glucose transporter protein
Colored corkscrews represent 3-D models of a sodium
glucose transporter protein, which propels glucose from
the intestine back into the bloodstream.
"This was a very challenging study that required innovation at each step of the process," said Abramson. "We literally had to invent new approaches to entice the protein into a crystal and then spent years optimizing these crystals to reach a quality suitable for visualization by X-rays. This would not have been possible without high-throughput protein production and purification capabilities."
An interesting observation made during the determination of the glucose transporter structure was the possibility for structural similarities with a previously crystallized neurotransmitter transporter molecule. Exploiting these similarities, along with computer modeling of structural dynamics, the researchers obtained the first atomic-level evidence for the mechanism underlying transport of glucose and neurotransmitters, such as serotonin, into cells. These results provide a fundamental understanding of how membrane proteins function in a dynamic manner.
Pharmaceutical companies already have extensive clinical trials underway to evaluate the use of inhibitors targeting SGLT1 and SGLT2 proteins to control blood glucose levels in diabetic patients by blocking intestinal glucose absorption and increasing glucose excretion into the urine. The UCLA findings will dramatically enhance the ability to rationally design these drugs.
In ongoing work, Wright and Abramson are examining the manner in which inhibitors of the transporter proteins modulate function, with the goal of facilitating better drug design for the treatment of diabetes, obesity and cancer.
The National Institute of Diabetes and Digestive and Kidney Diseases, and the American Heart Association helped support the study.
Co-authors included Salem Faham, Akira Watanabe, Gabriel Mercado Besserer and Bruce Hirayama, of the UCLA Department of Physiology; Duilio Cascio, of the UCLA Institute of Genomics and Proteomics; and Alexandre Specht, of Université Louis Pasteur.
Courtesy: UCLA Newsroom