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Lester Packer was an exceptional scientific leader, whose radiant personality inspired and encouraged generations of students and scientists for research to pursue oxidants and antioxidants in biology and medicine. For the FORUM dedicated to Professor Packer, we here describe key aspects of his professional career, from the early years at Brooklyn College, Yale University, and the Johnson Research Foundation at Philadelphia to his long-term base at the University of California, at UC Berkeley. The concept of the "Antioxidant Network" formed the core of his activities in later years. His welcoming and integrative personality led to a worldwide network of colleagues, starting with the Bay Area Oxygen Club, which turned into the Oxygen Club of California, and his leadership in the Society for Free Radical Research-International. To illustrate his warmth and outreach, which enabled him to form borderless global collaborations, we conclude with words from some of his many friends also from outside academia: Lester Packer's legacy. Antioxid. Redox Signal. 38, 768–774. [ABSTRACT FROM AUTHOR]

Aims Endothelial function is essential for cardiovascular health, and flow-mediated dilation (FMD) is an established technique to measure it. This paper aims to assess FMD values in apparently healthy individuals and provides reference values to facilitate wider clinical use. Methods and results In 1,579 apparently healthy individuals (aged 18–76), fasted FMD values (data from 44 studies, 6 institutions, 22 operators) were normally distributed and inversely univariately correlated with age, body mass index, glucose, cholesterol, blood pressure, and brachial artery (BA) diameter. Significant multivariate predictors of FMD were age (−0.4%/decade), BMI (0.04%/kg/m2), smoking (−0.7%), and BA diameter (−0.44%/mm) that together explained 19% of the variability independent of operator, institution or ultrasound machine. Individuals in the high FMD tertile (>6.8%) were younger, had smaller BA diameter, lower blood pressure and cholesterol. In individuals with low- and intermediate fatal cardiovascular risk (SCORE), 26% and 53% of individuals, respectively, had FMD values in the low tertile (<5.4%). After adding data from 385 patients with stable coronary artery disease (CAD), ROC analysis (c = 0.841 , P < 0.001) showed that FMD of >6.5% excluded CAD (95% sensitivity; 60% specificity) and FMD <3.1% excluded 95% healthy individuals (95% specificity, 31% sensitivity). A meta-analysis and meta-regression of 82 clinical trials (11 countries, n = 3,509) using similar FMD methodology showed that despite considerable heterogeneity (I 2 = 0.97) FMD in healthy individuals was on average 6.4% (95%CI: 6.2%, 6.7%) with no significant differences between countries but a significant age-dependent decline (−0.3%/decade, R 2 = 0.13). Conclusions We provide an age-adapted frame of FMD reference intervals in apparently healthy individuals for use as a biomarker of cardiovascular health. As the degree of vascular endothelial function integrates environmental and genetic factors with classical CV risk factors, FMD may more comprehensively classify individuals with and without standard modifiable cardiovascular risk factors and serve as a target for cardiovascular prevention. [ABSTRACT FROM AUTHOR]

The extended abstracts in this report are based on presentations from the 12th Special Conference on Functional Foods for Health Promotion, cosponsored by the North American branch of the International Life Sciences Institute (ILSI North America) Project Committee on Flavonoids and the American Society for Nutrition at the Experimental Biology meeting in April 2009. The theme of this year's special conference was 'State-of-the-Science on Dietary Flavonoids.' The conference began with a general introduction and overview offlavonoids and their presence in the diet as well as the estimated intake levels in the US population. Subsequent presentations addressed issues pertaining to study design and interpretation, mechanisms of action, and the potential health impacts related to inflammation, the vasculature, and the brain. The present summary of the current science indicates that dietary flavonoids, particularly flavanols, show promising potential for reducing cardiovascular disease risk via reduction of inflammation and improvement in vascular function. However, the existing data must be interpreted cautiously, with consideration given to the compound tested (i.e., parent or metabolite), the use of controls, and the practicality of the concentrations used. While more data are needed on the long-term health impacts of dietary flavonoids in humans, including the efficacious dose, current data indicate it may soon be possible to develop public health messages about flavonoid-rich foods. [c] 2009 International Life Sciences Institute doi: 10.1111/j.1753-4887.2009.00257.x

The subsequent years coincided with an explosion of interest in free radicals in biology generally, and Robin's contributions expanded rapidly to include major contributions to diverse areas of free radical chemistry and biology. The Newcastle group focused on reactions of radicals produced on radiolysis of aqueous solutions of nucleic acids, and Robin's first papers were in this area; he was awarded his PhD in 1966. It is with great sadness that we announce the passing of one of the "founding fathers" of the free radical and redox fields, Professor Robin Linhope Willson. In thinking about what highlights to include of the many discoveries associated with Robin Willson, and particularly those of the widest and most-enduring interest to the field of free radical chemistry and biology, the direct observation of the "repair" of radicals formed from the antioxidants, vitamin E and thiols, by ascorbate (vitamin C) immediately springs to mind [[1]]. [Extracted from the article]

Dietary antioxidants contribute to endogenous photoprotection and are important for the maintenance of skin health. In the present study, 2 groups of women consumed either a high flavanol (326 mg/d) or low flavanol (27 mg/d) cocoa powder dissolved in 100 mL water for 12 wk. Epicatechin (61 mg/d) and catechin (20 mg/d) were the major flavanol monomers in the high flavanol drink, whereas the low flavanol drink contained 6.6 mg epicatechin and 1.6 mg catechin as the daily dose. Photoprotection and indicators of skin condition were assayed before and during the intervention. Following exposure of selected skin areas to 1.25 x minimal erythemal dose (MED) of radiation from a solar simulator, UV-induced erythema was significantly decreased in the high flavanol group, by 15 and 25%, after 6 and 12 wk of treatment, respectively, whereas no change occurred in the low flavanol group. The ingestion of high flavanol cocoa led to increases in blood flow of cutaneous and subcutaneous tissues, and to increases in skin density and skin hydration. Skin thickness was elevated from 1.11 [+ or -] 0.11 mm at wk 0 to 1.24 [+ or -] 0.13 mm at wk 12; transepidermal water loss was diminished from 8.7 [+ or -] 3.7 to 6.3 [+ or -] 2.2 g/(h x [m.sup.2]) within the same time frame. Neither of these variables was affected in the low flavanol cocoa group. Evaluation of the skin surface showed a significant decrease of skin roughness and scaling in the high flavanol cocoa group compared with those at wk 12. Dietary flavanols from cocoa contribute to endogenous photoprotection, improve dermal blood circulation, and affect cosmetically relevant skin surface and hydration variables. KEY WORDS: * epicatechin * photoprotection * skin * human * flavonoids * blood flow

Astaxanthin is a carotenoid found in plants and algae; it provides the color of marine seafood such as salmon, lobster, or shrimp. Carotenoids are antioxidants and exhibit other biological functions, including effects on gap junctional communication important for homeostasis, growth control, and development of cells. Cancer cells have an impaired gap junctional intercellular communication. The objective of the present study was to determine the effects of astaxanthin and canthaxanthin on gap junctional intercellular communication in vitro. Primary human skin fibroblasts were exposed to carotenoids from 0.001 to 10 [micro]mol/L, and gap junctional communication was measured with a dye transfer assay. After incubation with canthaxanthin for 24 and 72 h, intercellular communication increased, whereas it was strongly diminished by astaxanthin at levels > 0.1 [micro]mol/L. Inhibition was reversed when astaxanthin was withdrawn. Western blot analysis showed that after exposure to canthaxanthin, the amount of the gap junction protein connexin43 was increased. Incubation with astaxanthin led to a change in the phosphorylation pattern of connexin43, shifting from higher to lower phosphorylation states. We suggest that astaxanthin affects channel function by changing the phosphorylation pattern of connexin43. KEY WORDS: * astaxanthin * canthaxanthin * carotenoids * connexin * gap junction * phosphorylation

Cocoa beans have historically been used as a treatment for diarrhea, leading us to hypothesize that polyphenols contained in cocoa inhibit intestinal [Cl.sup.-] secretion. In this study, the dose-dependent effects of flavonoid compounds present in cocoa, or molecularly closely related compounds, were tested on forskolin-stimulated cystic fibrosis transmembrane conductance regulator (CFTR)-mediated [Cl.sup.-] secretion across T84 colonic epithelia in Ussing chambers. Addition of cocoa extract or cocoa flavanols to the mucosal side of tissues caused partial inhibition following Michaelis-Menten kinetics and resulted in a rank order of maximum blocker effects as follows: epicatechin > catechin [greater than or equal to] standardized cocoa preparation [greater than or equal to] procyanidin B2. Half-maximal blocker concentrations ([K.sub.1]) were not substantially different between the tested preparations and were in the range of 100 [micro]mol/L. For comparison, the structurally related flavonoids, quercetin and luteolin, caused a total block of [Cl.sup.-] currents with [K.sub.i] values similar to the cocoa flavanols tested. Morin and baicalein were less effective blockers. Effects of test compounds on mucosal redox potential did not correlate with blocker activity. These data indicate that cocoa flavanols target intestinal CFTR [Cl.sup.1] transport and may serve as mild inhibitors of cAMP-stimulated [Cl.sup.-] secretion in the intestine. KEY WORDS: * diarrhea * CFTR [Cl.sup.-] channel * cocoa * flavonoids * CFTR blocker * redox potential