Leucine: A practical solution for muscle wasting?
As part of on-going research funded by NASA, scientists at the University of Texas medical branch have found that a measured approach to supplements could be the key to practical and feasible prevention of muscle wasting in bed-bound patients.
“This could potentially have a lot of application for hospitals and nursing homes or even individuals who are active and have been injured,” Dr Douglas Paddon-Jones, leader of the study, told NutraIngredients.
Building on past research
Over the past few years the researchers have looked at different age groups’ response to a 'cocktail' of essential amino acids and carbohydrates. “This worked well, it effectively prevented or really slowed down the loss of muscle,” explained Dr Paddon-Jones.
Within this earlier study where 13 healthy male volunteers were confined to beds for a 28-day period, it was found that those given the supplement mix lost half as much leg muscle as those who were given placebos.
Yet this would not be a practical solution for the kinds of patients most in need of this treatment, said Dr Paddon-Jones. “It tasted disgusting and it would be pretty expensive, you couldn’t just go out and buy the supplement.”
“The problem is that they [patients] quite often can’t or won’t consume enough food. They’re sick and a lot of the times they’re not interested in eating and there’s all sorts of associated costs and convenience issues too.”
A targeted response
Their latest wave of research focused on the potential use of the essential amino acid, leucine, only in the groups of middle-aged (45-60 years) and old aged patients confined to bed for 10 days. Three grams of leucine was added to their breakfast, lunch and dinner.
“Leucine acts as one of the building blocks that make up protein, but it is also kind of unique in that it acts as a trigger in turning on all of the protein synthesis pathways that start the muscle building process,” explained Dr Paddon-Jones. This allows patients to more efficiently use the regular protein already in their food.
“We’re not adding a lot of protein to people’s diets. This is absolutely not about just throwing a whole load of extra energy or food or protein at people because that won’t work. They’ll either get fat, they won’t eat it or they’ll become so full that they’ll skip the next meal.” Such an approach to intervention would be “dumb and blunt fisted,” said Dr Paddon-Jones.
“Three grams of leucine is what you would find in about 4 ounces, or 115 grams, of lean beef for example. So it’s not a lot, it’s a small amount.”
The use of this cheaper, smaller amount of supplement was found to be marginally less effective than the previous more complex supplement 'cocktail'.
This smaller amount, although also of an unpleasant taste, is far easier to hide in patients’ food in powder form.
The National Space Biological Research Institute study into the use of a leucine supplement has just been completed and is yet to be published.
Alongside this research, Dr Paddon-Jones and his colleagues are looking into the use of whey protein for the same purpose.