A new study indicates that the flavonol Pycnogenol can help improve memory in the elderly - findings the researchers say support putative benefits of antioxidants for cognitive function.
Pycnogenol is extracted from the bark of the Maritime pine that grows on the southern coast of France, and is currently used in over 400 dietary supplements, multi-vitamins and health products. It is made by Horphag Research and its US distributor is Natural Health Science.
It is thought that one of the main causes of ageing is damage to macromolecules caused by the reactive by-products of oxidative metabolism - and the ageing brain is particularly susceptible to oxidative injury.
In addition to examining the effects of Pycnogenol on a range of cognitive and biochemical measures in 101 seniors, aged between 60 and 80 years, the new study, which has been accepted for publication in the Journal of Psychopharmacology, also looked at this oxidative stress hypothesis of ageing and neurological degeneration in elderly individuals.
Conducted at the Centre for Neuropsychology at Swinburne University in Melbourne, Australia, the study used a double-blind, placebo controlled and matched-pairs design. The participants were divided into two groups which were matched by age, sex, body mass index, micronutrient intake and intelligence.
They received a daily dose of 150mg of Pycnogenol over a three month period, and were assessed at baseline, then one, two, and three months into the treatment. The assessment involved cognitive tasks, conducted using a computerised system, to measure attention, working memory, episodic memory and psycho-motor performance.
The researchers, led by Dr Con Stough, found that, after three months, the participants receiving Pycnogenol had "significantly improved" memory, as seen in a factor that combined accuracy scored from spatial working memory and numeric working memory tasks.
In addition, the team measured a number of biological markers: levels of clinical hepatic enzymes, serum lipid profile, human growth hormone and lipid peroxidation products.
The team found that there was a statistically significant relationship between memory-based cognitive variables and lipid peroxidation products. A marker known as F2-isoprostanes, which developed when unsaturated fatty acids are oxidised, was seen to be present in high quantities in the nerve cell membranes.
Study participants in the Pycnogenol group were seen to have improved performance on working memory measures and decreased concentrations of f2-isoprostanes, compared to those in the placebo group.
"These results support research from a range of disciplines that suggest that antioxiodants may have an effect in preserving or enhancing specific mental functions," said Dr Stough in a communication about the results. "Cognitive research in this area specifically indicates that the putative benefits associated with antioxidant supplementation are associated with memory."
However in the conclusion to the study, Stough said that further research should expand the study over two to three years, and with more subjects.
In addition, since molecular oxidative injury to neural cells over a period of more than five years is strongly associated with age-related cognitive impairment developing into Alzheimer's and Parkinson's disease, he said that further research should look at the effects of Pycnogenol in preventing these.
Pycnogenol has previously been researched for other cognitive function benefits, including in children affected by Attention Deficit Disorder.
Journal of Psycopharmacology
(publication issue not yet known)
"An examination of the effects of the antioxidant Pycnogenol on cognitive performance, serum lipid profile, endocrinological and oxidative stress biomarkers in an elderly population".
Authors: Jacob Ryan, Kevin Croft, Keith Wesnes and Con Stough