Primecuts – This Week In The Journals

February 19, 2013

By Aaron Smith

Faculty Peer Reviewed

Happy Belated Valentine’s Day! In this edition of Primecuts, we look at recent scientific articles pertaining to our favorite Valentine’s Day traditions. Next year, you may find the following information useful before you pour that bottle of wine, open that box of chocolates, or snuggle with that special someone.

Long believed to be an aphrodisiac, red wine is practically synonymous with love and romance. An article in Molecular Reproduction & Development supports red wine’s purported fertility-enhancing properties.[1] Aquila et al. examined the effects of the phytoestrogen myricetin on human sperm biology. Myricetin is a natural flavanoid, occurring widespread among plant species but particularly enriched in red wine. The authors exposed human sperm samples to increasing concentrations (10nM, 100nM, and 1?M) of myricetin and then analyzed sperm motility, viability, and biochemical changes. Sperm exposed to myricetin showed increased motility (25% at 10nM and 50% at 100nM), viability (20% at 10nM and 30% at 100nM), and increased biochemical activity for a host of reactions critical to sperm function. Myricetin increased the activity of specific proteins responsible for sperm capacitation in the female reproductive tract, it triggered the sperm acrosome reaction, and it increased sperm glucose and lipid metabolism. Notably, for all of the above variables, optimal results occurred at the 100nM, mid-level dose of myricetin, with decreased results at the 1?M, high-level dose. The authors note that further investigation is needed to better define the effects of high levels of myricetin, which could be obtained with moderate red wine consumption (1-2 glasses per day). Still, the authors show that the health benefits of red wine may be more complex than previously believed, and that there may be a scientific basis to red wine’s amorous reputation.

Red wine of course has a multitude of effects on human health. An article this week in Cardiovascular Drugs & Therapy adds to the already substantial trove of literature describing red wine’s effects on the cardiovascular system.[2] Resveratrol, a polyphenol found in red wine, has been known to have antiinflammatory properties. In a triple-blinded, randomized trial by Tomé-Carneiro et al., 75 patients with stable coronary artery disease (CAD) received 350 mg/day of a placebo, a grape extract lacking resveratrol, or a grape extract containing resveratrol. After one year, in contrast to the placebo and conventional grape extract groups, the resveratrol-containing grape extract group showed an increase in anti-inflammatory serum adiponectin (9.6%, p=0.01) and a decrease in thrombogenic plasminogen activator inhibitor type-1 (PAI-1) (-18.6%, p=0.05). The study supports the hypothesis that resveratrol contributes to red wine’s positive effects on the cardiovascular system, and suggests that resveratrol extract may be a useful supplement for patients with stable CAD.

Some would argue that chocolate, not wine, is the key to a romantic Valentine’s Day. A recent study in Molecular Nutrition & Food Research suggests that like red wine, chocolate may benefit the cardiovascular system.[3] Flavan-3-ol, a polyphenol abundant in dark chocolate, has been hypothesized to have beneficial effects on platelet function. In this study by Ostertag et al., 42 subjects were randomly fed flavan-3-ol-enriched dark chocolate, normal dark chocolate, or white chocolate. Blood and urine samples were obtained before consumption and at two and six hours after consumption, and measured for markers of platelet function and for bioavailability and excretion of flavan-3-ols. The flavan-3-ol-enriched dark chocolate, and to a lesser extent the normal dark and white chocolate, were all found to decrease platelet aggregation. Surprisingly, however, the mechanism appeared to be gender-specific. For example, enriched dark chocolate decreased adenosine diphosphate activity in men but not in women (p?0.020), while it decreased thrombin receptor-activating peptide activity in women but not in men (p?0.041). Nevertheless, flavan-3-ol-containing compounds may beneficially affect atherogenesis in both genders. A Valentine’s Day filled with wine and chocolate may lead not only to romance, but to a healthy heart.

Red wine, dark chocolate…Eurycoma longifolia Jack? An article in the Journal of Ethnopharmacology suggests that E. longifolia Jack, a small tree known as “Tongkat Ali” in Malaysia, may be useful as an aphrodisiac and fertility enhancer.[4] In this study Low et al. fed rats various extracts of E. longifolia root. Compared with control animals, rats fed the extract had higher LH and FSH levels (p<0.001), lower estrogen levels, increased sperm concentration (p<0.05), increased number of spermatocytes and round spermatids (p<0.05), and increased number of Leydig cells (p<0.001). Consequently the animals had a higher fertility index, fecundity index, and pup litter size. The authors conclude that E. longifolia improves spermatogenesis in rats by affecting the hypothalamic-pituitary-gonadal axis, and may be worthy of further investigation as a treatment for male infertility. Perhaps one day “Tongkat Ali” will find itself on the table next to wine, chocolate, oysters, and strawberries.

Finally, here are a few non-Valentine’s Day-related highlights from the previous week:

1. Schuepbach WMM, Rau J, Knudsen K, et al. Neurostimulation for Parkinson’s Disease with Early Motor Complications. N Engl J Med. 2013;368(7):610–622. http://www.nejm.org/doi/full/10.1056/NEJMoa1205158

For patients at early stages of Parkinson’s Disease, subthalamic neurostimulation was compared to medical therapy and resulted in higher quality of life.

2. Surén P, Roth C, Bresnahan M, et al. Association Between Maternal Use of Folic Acid Supplements and Risk of Autism Spectrum Disorders in Children. JAMA. 2013;309(6):570-577. http://jama.jamanetwork.com/article.aspx?articleid=1570279

Use of prenatal folic acid supplements around the time of conception was associated with a lower risk of autistic disorder for a sample of 85,176 children derived from the population-based, prospective Norwegian Mother and Child Cohort Study (MoBa).

3a. Atkin W, Dadswell E, Wooldrage K, et al. Computed tomographic colonography versus colonoscopy for investigation of patients with symptoms suggestive of colorectal cancer (SIGGAR): a multicentre randomised trial. Lancet. 2013. http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)62186-2/fulltext

3b. Halligan S, Wooldrage K, Dadswell E, et al. Computed tomographic colonography versus barium enema for diagnosis of colorectal cancer or large polyps in symptomatic patients (SIGGAR): a multicentre randomised trial. Lancet. 2013. http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)62124-2/fulltext

Two “online first,” randomized, controlled trials published in The Lancet support more widespread use of computed tomographic (CT) colonography as an alternative to colonoscopy and barium enema in the detection of colorectal cancer.

Aaron Smith is a 4th year medical student at NYU School of Medicine

Peer reviewed by Robert Gianotti, Associate Editor, Clinical Correlations

Image courtesy of Wikimedia Commons

References:

1. Aquila S, Santoro M, De Amicis F, et al. Red wine consumption may affect sperm biology: The effects of different concentrations of the phytoestrogen Myricetin on human male gamete function. Mol. Reprod. Dev. 2013;80(2):155–165. http://onlinelibrary.wiley.com/doi/10.1002/mrd.22145/full

2. Tomé-Carneiro J, Gonzálvez M, Larrosa M, et al. Grape resveratrol increases serum adiponectin and downregulates inflammatory genes in peripheral blood mononuclear cells: a triple-blind, placebo-controlled, one-year clinical trial in patients with stable coronary artery disease. Cardiovasc Drugs Ther. 2013;27(1):37–48. http://link.springer.com/article/10.1007/s10557-012-6427-8/fulltext.html

3. Ostertag LM, Kroon PA, Wood S, et al. Flavan-3-ol-enriched dark chocolate and white chocolate improve acute measures of platelet function in a gender-specific way-a randomized-controlled human intervention trial. Mol Nutr Food Res. 2013;57(2):191–202. http://onlinelibrary.wiley.com/doi/10.1002/mnfr.201200283/full

4. Low B-S, Das PK, Chan K-L. Standardized quassinoid-rich Eurycoma longifolia extract improved spermatogenesis and fertility in male rats via the hypothalamic-pituitary-gonadal axis. J Ethnopharmacol. 2013;145(3):706–714. http://dx.doi.org/10.1016/j.jep.2012.11.013

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