Hormone injection curbs appetite and ups activity

Topping up levels of the hormone oxyntomodulin found in the gut could help reduce appetite and increase physical activity in overweight and obese people, new research suggests.

The study, released online on Wednesday by the International Journal of Obesity, was carried out by a team led by Professor Steven Bloom, from Imperial College London, who has set up a spin-out company, Thiakis, to commercialise the discovery.

The team gave injections of oxyntomodulin to 15 overweight but healthy volunteers aged 23 to 49, and monitored how this affected their food intake and levels of activity.

The volunteers completed three separate four-day study sessions, where they self-administered either saline or oxyntomodulin according to a randomised protocol.

After the first injection, the volunteers were given a meal, and their calorific intake was monitored. They spent the next two days in their normal environment, self-administering the infusions three times a day before meals.

On the fourth day, the volunteers returned to the hospital to have their energy expenditure measured.

They found that after the first meal, the volunteers given oxyntomodulin ate on average 128 kcal or 17.4 percent less, while activity related energy expenditure increased by an average of 143 kcal or 26.2 percent.

The researchers also found a reduction in body weight by an average of 0.5 percent.

Professor Bloom said: "The discovery that this hormone has a double effect, increasing energy expenditure as well as reducing food intake, could be of huge importance.

"When most people diet, this produces a reduction in activity, which is probably an adaptive trait to conserve energy during times of famine. However, this does make it especially difficult for obese individuals trying to lose weight.

"In contrast, oxyntomodulin decreases calorific intake, but actually increases energy expenditure, making it an ideal intervention for the obese."

NO PARTNER YET

Bloom told APM he has still not found a commercial partner "although we're still looking".

He believes the absence of a partner might be due to the fact the product needs to be administered via injection. But he said it could be injected in the same "painless way" that diabetics inject insulin using the 'pen' system.

"It could be done completely painlessly just with one click. Lots of people, from young children to blind grannies, think nothing of it."

Bloom added in the report: "This discovery could provide doctors with a whole new way to treat the current obesity epidemic. We need to get away from the focus on food and start to think about how to increase exercise. The question is how to make people enjoy taking exercise and how to encourage them to do it spontaneously.