The study, published in Nature Communications, used animal models including nematode worms (Caenorhabditis elegans) and mice to demonstrate that D-glucosamine (GlcN) extends life span by impairing glucose metabolism that activates AMP-activated protein kinase, and increases mitochondrial biogenesis.
Led by Dr Michael Ristow from ETH Zurich, the team noted that glucosamine supplementation has been linked to beneficial effects against arthritis and in the prevention joint degeneration, in addition to reported anti-cancer properties.
"The current findings indicate that GlcN at pharmacologically relevant concentrations is capable of extending life span in C. elegans and ageing mice," wrote the research team.
"This appears to be a result of decreased glycolysis and a compensatory increase of amino-acid turnover."
Animal models
Ristow and his colleagues first supplemented roundworms with glucosamine - finding that they lived around 5% longer than their non-supplemented counterparts.
Next and perhaps most importantly, the team fed glucosamine to ageing mice in addition to their normal diet.
The mice were 100 weeks of age, reflecting a comparative human age of approximately 65 years. A control group of mice received no glucosamine while otherwise receiving an identical diet.
Feeding the supplement to mice extended their lifespan by almost 10%, said the team - adding that this reflects around 8 additional years of human lifespan.
Moreover, glucosamine improved glucose metabolism in elderly mice indicating protection from diabetes, a life-threatening disease most prevalent amongst the elderly.
Mimicking a low-carb diet?
Further analysis by Ristow and his team revealed that glucosamine feeding promotes the breakdown of amino acids in both worms and mice.
"This reflects the metabolic state of a low-carb diet due to glucosamine supplementation alone – while these mice ingested the same amount of carbohydrates as their unsupplemented counterparts," said Ristow - who suggested that the findings imply that glucosamine could mimic a low-carb diet in humans as well, without the necessity of reducing the uptake of carbohydrates in our daily diet.