Hypertension, the Kuna, and the epidemiology of flavanols.
ABSTRACT A low sodium diet has often been implicated in the protection of low blood pressure populations from hypertension, but several other dietary factors, including those as yet unidentified, may also be involved. The Kuna Indians of Panama are free of hypertension and cardiovascular disease, but this is changing with migration to urban areas. We compared the indigenous diet of Kuna Indians living on remote islands in Panama (Ailigandi), whose lifestyle is largely hunter-gatherer, with those who have moved to a suburb of Panama City (Vera Cruz). Between April and October 1999, members of a Kuna research team administered a 118-item food frequency questionnaire to133 adult Kuna from Ailigandi and 183 from Vera Cruz. Single 24-hour urine collections and nonfasting blood samples were obtained. The Kuna in Ailigandi reported consuming a 10-fold higher amount of cocoa-containing beverages, 4 times the amount of fish, and twice the amount of fruit as urban Kuna (P<0.05 by t test). Salt added was ample among those living in Ailigandi and Vera Cruz according to both self-report (7.1+/-1.1 and 4.6+/-0.3 tsp weekly) and urinary sodium levels (177+/-9 and 160+/-7 mEq Na/g creatinine), respectively. The low blood pressure of island-dwelling Kuna does not seem to be related to a low salt diet. Among dietary factors that varied among migrating Kuna, the notably higher intake of flavanol-rich cocoa is a potential candidate for further study.
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ABSTRACT: Throughout the recent past, there has been an increasing awareness of and movement towards organic food and natural products. At the same time, with the steady incline in life expectancy, we have become increasingly dependent on a large list of pharmaceutical drugs. With recent insight into the mechanisms involved in diseases, such as cardiovascular disease, cancer, stroke, neurodegenerative diseases, and diabetes, more efficient modes of treatment are now being assessed. Traditional medicine is widely practiced around the world, assuming that certain natural products contain the healing properties that may in fact have a preventative role in many of the diseases plaguing the human population. This article reviews the biological effects of a group of natural compounds called polyphenols, including apigenin, epigallocatechin gallate, genistein, and (-)-epicatechin, with a focus on the latter. (-)-Epicatechin has several unique features responsible for a variety of its effects. One of these is its ability to interact and neutralize reactive oxygen species (ROS) in the cell. (-)-Epicatechin also modulates cell signaling including the MAP kinase pathway, which is involved in cell proliferation. Mutations in this pathway are often associated with malignancies, and the use of ()epicatechin holds promise as a preventative agent and as an adjunct for chemo and radiation therapy to improve outcome. This article discusses the potential of these compounds to maintain, protect, and possibly reinstate health.Oxidative medicine and cellular longevity 12/2014; · 3.36 Impact Factor
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ABSTRACT: Background and aim Hypertension is one of the main cardiovascular risk factors in the elderly. The aims of this work were to evaluate if a one-year intervention with two Mediterranean diets (Med-diet) could decrease blood pressure (BP) due to a high polyphenol consumption, and if the decrease in BP was mediated by plasma nitric oxide (NO) production. Methods and Results An intervention substudy of 200 participants at high cardiovascular risk was carried out within the PREDIMED trial. They were randomly assigned to a low-fat control diet or to two Med-diets, one supplemented with extra virgin olive oil (Med-EVOO) and the other with nuts (Med-nuts). Anthropometrics and clinical parameters were measured at baseline and after one year of intervention, as well as BP, plasma NO and total polyphenol excretion (TPE) in urine samples. Systolic and diastolic BP decreased significantly after a one-year dietary intervention with Med-EVOO and Med-nuts. These changes were associated with a significant increase in TPE and plasma NO. Additionally, a significant positive correlation was observed between changes in urinary TPE, a biomarker of TP intake, and in plasma NO (Beta= 4.84; 95% CI: 0.57 to 9.10). Conclusions TPE in spot urine sample was positively correlated with plasma NO in Med-diets supplemented with either EVOO or nuts. The statistically significant increases in plasma NO were associated with a reduction in systolic and diastolic BP levels, adding to the growing evidence that polyphenols might protect the cardiovascular system by improving the endothelial function and enhancing endothelial synthesis of NO.Nutrition Metabolism and Cardiovascular Diseases 09/2014; 25(1). DOI:10.1016/j.numecd.2014.09.001 · 3.88 Impact Factor
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ABSTRACT: Plant metabolism creates complex mixtures of polyphenols in plant foods. Epidemiology and human trials reduced this complexity, by studying specific foods; subclasses of polyphenols; individual polyphenols, or total antioxidant capacity (TAC). This implies the following assumptions: 1) a limited number of potent polyphenols exists; 2) well-defined natural potent mixtures of polyphenols exist; 3) polyphenols share a common biological activity (e.g. antioxidant activity). To find potent polyphenols (1st assumption), in vitro screening has been widely applied, but most published results are of limited use because metabolism, changing biological activity profoundly, has frequently not been considered. The abundant anecdotal evidence for natural potent mixtures of polyphenols (2nd assumption) on the internet is very hard to verify. Additionally, cross-cultural studies have revealed the potency of e.g. cocoa. Polyphenols share the antioxidant phenolic group which inspired researchers to measure their antioxidant activity, thus greatly reducing complexity (3rd assumption). Unfortunately, the elegant antioxidant hypothesis has to be rejected, because poor absorption and extensive metabolism annihilate any contribution to the endogenous body antioxidants. In conclusion, the above assumptions are hard to verify, and no quick answers are to be expected. Future research should focus on structure-activity relations at nanomolar levels and explore metabolomics.Archives of Biochemistry and Biophysics 05/2014; DOI:10.1016/j.abb.2014.04.013 · 3.04 Impact Factor