Scientists have developed a patent-pending vitamin B12 system and are using this to deliver the PYY hormone, reported to promote the feeling of fullness.
Preliminary research published in the Journal of Medicinal Chemistry indicated that a molecular complex between vitamin B12 and PYY may protect the hormone on passage through the stomach and into the intestines, allowing uptake into the blood system.
Once in the blood, the hormone can exert its satiating effects, making people feel fuller for longer.
Translated to humans
Researchers from Syracuse University in New York and Murdoch University in Australia tested the effects of their B12-PYY complex in lab rats and found a “clinically relevant” increase in blood levels of PYY, and this effect was sustained for the length of the experiment.
“This number also represents a clinically relevant dose should it translate to humans,” wrote the researchers.
“With the dose achieved and lifetime noted, this uptake profile bodes well for future clinical investigations. To explore these highly positive results further, full dose-delivery studies and studies pertaining to function now need to be undertaken.”
According to Syracuse’s Robert Doyle, the next step involves finding ways to insert the B12-PYY system into chewing gum or an oral tablet to create a nutritional supplement.
"If we are successful, PYY-laced gum would be a natural way to help people lose weight," he says. "They could eat a balanced meal, then chew a stick of gum. The PYY supplement would begin to kick in about three to four hours later, decreasing their appetite as they approach their next meal."
Dr Doyle confirmed to NutraIngredients-USA that “PYY is a natural hormone and should be able to pass as a supplement without FDA approval”.
An industrial partner is involved, he added, but would not identify the company.
With the World Health Organization estimating that by 2015, there will be more than 1.5 billion overweight consumers, the opportunities for a scientifically-substantiated weight management product are impressive.
The market for food, beverage and supplement weight management products is already valued at $3.64bn (2009 figures) in the US, according to Euromonitor. In Western Europe, the market was worth $1.3bn in 2009.
Boosting satiety has been a focus of numerous nutritional approaches, with gut hormones PYY and GLP-1 common targets. As people eat, they release PYY into the bloodstream, and the amount of PYY released increases with the number of calories that are consumed.
Oral delivery of PYY is also difficult since the hormone is readily inactivated in the harsh conditions of the stomach.
Dr Doyle has previous tested vitamin B12 as a vehicle for the oral delivery of insulin, due to the ability of B12 to pass through the digestive system relatively easily and carry substances into the bloodstream.
The researchers then tested the patent-pending vitamin B12 system as a vehicle for PYY.
"Phase one of this study was to show that we could deliver a clinically relevant amount of PYY into the bloodstream," said Doyle. "We did that, and we are very excited by the results."
A complex was formed using a two-step coupling reaction between vitamin B12 (cyanocobalamin) and hPYY. This was then tested in lab rats.
Results showed that the PYY levels increased in the lab animals to levels comparable to those observed after the animals have eaten.
“Given that humans have a far greater B12 uptake capacity than rats (rat is about 9−13 picomoles per dose, with humans about 0.7−1.4 nmol per dose), this work then suggests that the system described herein may be suitable for delivering clinically relevant doses of hPYY in humans (with suitable dose delivery studies performed to maximize/ optimize delivery),” wrote the researchers.
Source: Journal of Medicinal Chemistry
Published online ahead of print, Articles ASAP, doi: 10.1021/jm2012547
“Oral Delivery of the Appetite Suppressing Peptide hPYY(3–36) through the Vitamin B12 Uptake Pathway”
Authors: C.H. Fazen, D. Valentin, T.J. Fairchild, R.P. Doyle