Impaired blood circulation in diabetics may cause tissue damage and discolouration (necrobiosis) which leads to development of ulcers, which can be prone to infection and difficult to heal, said study researcher, Dr. Gianni Belcaro from Chieti-Pescara University in Italy.
"In this pilot study, oral Pycnogenol improved microcirculatory parameters and, consequently, ulcer healing, as indicated by the reduction in ulcer area and symptoms compared with the control group," wrote Belcaro in the the journal Clinical and Applied Thrombosis/Hemostasis (Vol. 12, No. 3, pp. 318-323, doi: 10.1177/1076029606290133).
The researchers randomly assigned 30 diabetic patients suffering from severe damage of blood vessels associated with their diabetes (microangiopathy) to one of four groups for six weeks.
Group 1 participants received 150 mg Pycnogenol as oral treatment and 100 mg from capsules as powder placed on the ulcerated area (local); Group 2 participants received oral treatment Pycnogenol with 150 mg; Group 3 received 100 mg of local treatment and Group 4 received no medical care, other then the same ulcer care as the other subjects (washed and cleaned with warm water and local disinfectant).
At the end of the study the researchers found that group 1 patients supplemented with oral and local pine bark extract experienced a 74.4 per cent decrease in leg ulcer size. Groups 2 and 3 experienced a 41.3 and 33 per cent decrease in ulcer size, respectively, while the control group's ulcers (Group 4) decreased by only 22 per cent. No adverse effects were reported, said the researchers.
The mechanism behind the effects was not investigated fully but the researchers proposed a role for the extract in improving glucose metabolism, anti-inflammatory effects, or improved circulation.
Indeed, this last mechanism appeared to be favoured by the researchers.
"The Pycnogenol groups all showed a significantly increased oxygen presence in the skin and a significantly lowered carbon dioxide level," noted Dr. Belcaro. "Better circulation decreases the chance of developing ulcers."
"If left untreated, damage to blood vessels from diabetes then manifests in typical circulatory problems such as hypertension, from which 50 per cent of type II diabetics suffer," he said.
While these results appear promising significantly more research is needed to confirm these results. Indeed, the researchers themselves called for larger, controlled studies to test if the pine bark extract could offer a "safe alternative to existing therapies".
Matt Hunt, science officer at British charity, Diabetes UK told NutraIngredients.com: "Lower limb ulcers in diabetes is often a neglected area and this research shows that combining treatments looks an effective method of treatment in area that can lead to more serious consequences such as amputation."
Horphag Research, manufacturers of Pycnogenol, has been very active in sponsoring and supporting studies into the potential health benefits of the pine bark extract. The extract has been claimed to have beneficial effects on a wide range of medical conditions from diabetes to asthma. It has also been proposed to boost male fertility and improve the memory of mice.
The authors of the current study do not disclose the source of their funding.
The product 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.