Yang HM, Liao MF, Zhu SY, Liao MN, Rohdewald P. A randomised, double-blind, placebo-controlled trial on the effect of Pycnogenol on the climacteric syndrome in peri-menopausal women. Acta Obstet Gynecol Scand. 2007;86(8):978-985.
A randomized, double-blind, placebo-controlled study of 200 peri-menopausal Taiwanese women analyzed the effect of pine bark extract (Pycnogenol®, 200 mg daily) on menopausal symptoms. After 6 months, the participants completed the Women's Health Questionnaire, which demonstrated the climacteric symptom-relieving characteristics of Pycnogenol as compared to the placebo group. The authors concluded that because Taiwanese women report differing peri-menopausal symptoms compared to European women, this study should be expanded to other populations of women.
Nishioka K, et al. Pycnogenol, French maritime pine bark extract, augments endothelium-dependent vasodilation in humans. Hypertens Res 2007;30(9):775-780.
The effect of Pycnogenol on forearm blood flow in response to endothelial-dependent (acetylcholine, Ach) and independent (sodium nitroprusside, SNP) vasodilators was assessed in this small, double-blind, randomized, placebo-controlled study of 16 healthy men. Participants either received placebo or Pycnogenol (180 mg daily) for 2 weeks before forearm blood flow was measured. Although Pycnogenol alone did not affect forearm blood flow, Ach-dependent forearm blood flow was increased in the Pycnogenol-treated group, an effect that was reversed upon administration of a NO synthase inhibitor. Pycnogenol did not influence vasodilation mediated by SNP, indicating that Pycnogenol influences endothelial-dependent vasodilation most likely through enhancing NO synthesis. Further studies with larger numbers of participants are required to determine if Pycnogenol is beneficial in subjects with oxidative stress-related diseases.
Ryan J, et al. An examination of the effects of the antioxidant Pycnogenol on cognitive performance, serum lipid profile, endocrinological and oxidative stress biomarkers in an elderly population. J Psychopharmacol 2008;22(5):553-562.
In a double-blind, placebo-controlled, matched-paired study, the effect of Pycnogenol on cognitive function and serum lipid profiles was assessed in 101 elderly participants. After 3 months, working memory was enhanced in the participants receiving Pycnogenol (150 mg/day) as compared to the placebo group. The authors surmise that this enhancement may be due to the anti-oxidant activity of Pycnogenol. Larger, long term studies are necessary to full determine the clinical benefits of Pycnogenol supplementation on memory.