Scientists believe that two drugs which have already been approved by the US Food and Drug Administration (FDA) may provide new forms of obesity treatment.
Researchers at Harvard Medical School have shed light on resistance to the hormone leptin, which usually signals the brain to stop eating when a person has eaten enough.
Many obese people do not respond to this hormone, leading them to continue eating and put on excess weight.
Scientists have now shown that leptin resistance can be brought on by a condition called endoplasmic reticulum (ER) stress and that mice with induced ER stress were more likely to become obese when given a high-fat diet.
They also discovered that this process could be reversed in mice by giving them one of two existing drugs - 4-Phenyl Butyric Acid (PBA) and Tauroursodeoxycholic acid (TUDCA).
Researcher Umut Ozcan said that the finding was "very exciting" and that re-sensitising people to leptin "could treat obesity".
"When the high safety profiles of PBA, TUDCA and leptin are taken into consideration, our results may define a novel treatment option for obesity," he claimed.
The findings are published in the journal Cell Metabolism and are likely to be welcomed by obesity experts, many of whom are concerned by the government's recent Foresight report that predicted some 60 per cent of English men and 50 per cent of women could be clinically obese by 2050.
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