Back in 1999, researchers discovered a hormone called ghrelin that helps control appetite in animals and people. Now researchers are saying that a vaccine that slows down ghrelin has successfully kept lab rats from gaining weight… even when they over-ate.
The study on vaccination against ghrelin in rats was performed by the Scripps Research Institute in California. The vaccine enables the immune system to recognize something it doesn’t ordinarily recognize — the hormone ghrelin. When the immune system doesn’t allow ghrelin to reach the brain, the rats in the trial that ate normally ended up losing weight.
Although the vaccine was successful in slowing weight gain and fat build-up in rats, it may not work in humans. Even testing with human volunteers is a long way off — a spokesperson for Scripps said human testing was at least two years away. If nothing else, the study showed researchers a lot about how hunger and weight gain work.
For the hormone to impact appetite and weight gain, it has to move from the bloodstream into the brain. Over long periods of time, ghrelin stimulates fat storage for energy. Suppressing ghrelin appears to help control whether the body stores fat or burns it off… at least in rats. The Scripps Research Institute believes that their study is the first published evidence proving that an active vaccination inhibiting ghrelin can produce a reduction in weight gain.
So what’s next? The folks at Scripps hope that the vaccine can help people avoid yo-yo dieting. The results of the study may not answer the question of treating obesity once and for all… but they hope that active immunization against ghrelin can be a workable solution to weight problems.
However… researchers aren’t sure whether or not a ghrelin vaccine would be useful against a high-fat diet. The rats enjoyed a low-fat, low-energy diet during the study.
Meanwhile, a biotechnology company in Sweden called Cytos is already testing a vaccine against ghrelin in humans. It works differently from the Scripps vaccine — the Cytos vaccine prevents the uptake of ghrelin in the brain, rather than stimulating the immune system to produce antibodies like the Scripps vaccine does.