Dicentra Newsletter – Issue #12

December 15, 2010 By

Science and Research Updates

R.H.X. Wong, P.R.C. Howe, J.D. Buckley, A.M. Coates, I. Kunz, N.M. Berry. Acute resveratrol supplementation improves flow-meditated dilation in overweight/obese individuals with mildly elevated blood pressure. Science Direct, March 2010.

Impaired flow-meditated dilation of the brachial artery (FMD) is associated with cardiovascular risk factors including hypertension and obesity. This study investigated whether consuming resveratrol, a polyphenol found in red wine can enhance FMD acutely and whether there is a dose-response relationship for this effect. Fourteen overweight/obese men and 5 post-menopausal women with untreated borderline hypertension consumed 3 doses of resveratorl and a placebo at weekly intervals in this double-blind crossover comparison. Plasma resveratrol and FMD were measured one hour after supplement consumption. With increasing doses of resveratrol, there were proportional increases in plasma resveratrol concentration, and linear regression analysis revealed a significant relationship. Furthermore, a significant linear relationship between plasma resveratrol concentration and acute FMD. These results are encouraging but further research is needed to determine whether the improvement seen in FMD after oral resveratrol supplementation is sustainable over the long-term.

Lemke SL, Vicini JL, Su H, Goldstein DA, Nemeth MA, Krul ES, Harris WS. Dietary intake of stearidonic acid-enriched soybean oil increases the omega-3 index: randomized, double-blind clinical study of efficacy and safety. Am J Clin Nutr. 2010 Aug 25. [Epub ahead of print].

The benefits of omega-3 (n-3) long chain polyunsaturated fatty acids (LCPUFAs), eicosapentaenoic (EPA) and docoshexaenoic acids (DHA) in reducing cardiovascular disease (CVD) are supported in the literature. To recieve these benefits, the American Heart Association (AHA) recommends that individuals eat a variety of fatty fish at least twice a week, and even often more for those suffering from CVD. The most common land-based n-3 fatty acid is α-linoleic acid (ALA), but its conversion rate to EPA in vivo is exceedingly low. Stearidonic acid (SDA) is the product of the rate-limiting step in the synthesis of EPA from ALA and thus is more readily converted to EPA than ALA is. Therefore, the present double-blind study aimed to compare the effect of SDA-enriched soybean oil with that of EPA and soybean oil on the omega-3 index over a 12 week period. Additionally, secondary endpoints measured include: serum triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, systolic blood pressure, diastolic blood pressure, heart rate, high sensitivity C-reactive protein (Hs-CRP), adiponectin and EPA, DHA and SDA as percentages of total lipids in the red blood cell membrane. Two hundred and fifty-two healthy individuals randomly received soybean oil only (control), 1 g EPA with soybean oil or soybean oil enriched with 4.2 g SDA each day. Treatment with EPA and SDA resulted in a higher omega-3 index when compared to the placebo-controlled group and no differences observed between the EPA and SDA groups. The higher omega-3 index was a result of the increase in EPA levels within the red blood cell membrane. No significant changes were observed in any of the additional secondary endpoints. As for safety assessment, no SDA-specific adverse reactions were observed. In cloncusion, the results of this study suggest that SDA as effective as EPA in increasing tissue EPA levels.

Yen CH, Tseng YH, Kuo YW, Lee MC, Chen HL. Long-term supplementation ofisomalto-oligosaccharides improved colonic microflora profile, bowel function, and blood cholesterol levels in constipated elderly people-A placebo-controlled, diet-controlled trial. Nutrition. 2010 Jul 10. [Epub ahead of print].

Impaired bowel function, particularly constipation, is a common complaint of ill or inactive elderly people. Populations with poor chewing ability need suitable dietary fibre which can easily be incorporated into their ordinary diet to maintain regular bowel movements. Isomalto-oligosaccharides (IOs) exist naturally in Japanese foods such as miso and soy sauce. IOs are commercially produced from corn starch as a functional food ingredient. The aim of this double-blind, placebo-controlled study was to evaluate the effects IO on fecal microflora, bowel function and fecal short chain fatty acids in constipated elderly subjects over an 8 week period. Subjects consumed an afternoon drink containing 5 g of IO for the first 4 weeks which was gradually increased to provide 10 g IO daily for the last 4 weeks of the study. Additionally, all participants consumed an identical diet throughout the study. Supplementation with 5 and 10 g IO resulted in significant increases in fecal counts of bifidobacteria, lactobacilli, bacteriodes and total bacteria. Moreover, following supplementation, the fecal clostridia content decreased significantly when compared to pacebo-control. The number of spontaneous bowel movements and amount of stool output were significantly increased following supplementation with 10 g IO daily, but this increase was not observed post-treatment. Additionally, the daily outputs of total short chain fatty acids significantly increased following supplementation with IO when compared to placebo-control. In conclusion, supplementation with IO improved bowel function and promoted the growth of health gut microflora, while decreasing the growth of harmful bacteria, i.e. clostridia. Clostridia are pathogenic to humans and decreasing the amount of this type of bacteria from the bowel may help protect from illness. Overall, supplementation with IO functioned as prebiotic to stimulate to growth of healthy gut bacteria while reducing the presence of pathogenic types of bacteria in the bowels of elderly people.

Thank you for reading, if you have any comments or questions, we can be reached at 1-866-647-3279 or at dicentra.com


Ashleigh Hampton