Discovery in S.Korea promises dieting without limits on eating

A drug candidate in South Korea could allow people seeking to lose weight to eat to their heart's content.

The Center for Cognition and Sociality of the Institute for Basic Science, an affiliate of the Ministry of Science and ICT, on Thursday said it developed KDS2010, which was found to effectively reduce weight regardless of the volume of food consumed based on tests on animals. 

The brain's lateral hypothalamus controls hunger and body energy balance. Lateral hypothalamic neurons connected to fatty tissue are known to be involved in fat metabolism, but the exact mechanism for controlling such metabolism remains unknown.

The center's research team discovered GABRA-5, a nerve cell cluster that expresses the inhibitory neutral receptor GABA in the lateral hypothalamus. Tests on obese mice found that suppression of GABRA-5 activity reduced heat generation (exhaustion of energy) in fatty tissue, causing accumulation of fat and increase in body weight. Conversely, the pounds came off when GABRA-5 was activated, showing that the cluster could be a "weight control switch."

The study also found that astrocytes, or star-shaped non-neural cells in the lateral hypothalamus, regulate GABRA-5 activity.

A rise in astrocytes resulted in the release of the enzyme MAO-B and mass production of persistent GABA, which led to the suppressing of GABRA-5. Conversely, inhibition of the enzyme activated GABRA-5 and raised heat generation in fatty tissue, which caused weight loss even when the mice ate a lot.

Inhibiting the MAO-B enzyme, KDS2010 will see clinical trials from next year.

Nature Metabolism, a sister publication of the London-based Nature, one of the world's top three academic journals, carried the results of the study, in which the Korea Advanced Institute of Science and Technology and Ulsan National Institute of Science and Technology participated.

Write to Hae-Sung Lee at ihs@hankyung.com