Higher dietary flavone, flavonol, and catechin intakes are associated with less of an increase in BMI over time in women: a longitudinal analysis from the Netherlands Cohort Study

BACKGROUND: Dietary flavonoids are suggested to have antiobesity effects. Prospective evidence of an association between flavonoids and body mass index (BMI) is lacking in general populations. OBJECTIVE: We assessed this association between 3 flavonoid subgroups and BMI over a 14-y period in 4280 men and women aged 55-69 y at baseline from the Netherlands Cohort Study. DESIGN: Dietary intake was estimated at baseline (1986) by a validated food-frequency questionnaire. BMI was ascertained through self-reported height (in 1986) and weight (in 1986, 1992, and 2000). Analyses were based on sex-specific quintiles for the total intake of 6 catechins and of 3 flavonols/flavones. Linear mixed effect modeling was used to assess longitudinal associations in 3 adjusted models: age only, lifestyle (age, energy intake, physical activity, smoking status, alcohol intake, type 2 diabetes, and coffee consumption), and lifestyle and diet (vegetables, fruit, fiber, grains, sugar, dessert, and dieting habits). RESULTS: After adjustment for age and confounders, the BMI (kg/m(2)) of women with the lowest intake of total flavonols/flavones and total catechins increased by 0.95 and 0.77, respectively, after 14 y. Women with the highest intake of total flavonols/flavones and total catechins experienced a significantly lower increase in BMI of 0.40 and 0.31, respectively (between group difference: P < 0.05). This difference remained after additional adjustment for dietary determinants and after stratification of median baseline BMI. In men, no significant differences in BMI change were observed over the quintiles of flavonoid intake after 14 y. CONCLUSION: Our results suggest that flavonoid intake may contribute to maintaining body weight in the general female population. AD - .s FAU - Hughes, Laura A E AU - CN - Netherlands Cohort Study LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - United States TA - Am J Clin Nutr JT - The American journal of clinical nutrition JID - 0376027 SB - AIM SB - I

We’ve Been Down this Road Before: Evidence on the Health Consequences of Precarious Employment in Industrial Societies, 1840-1920

A large body of international scientific research now indicates that the growth of job insecurity, flexible/temporary work and precarious forms of self-employment have had significant negative consequences for occupational health and safety. What is often overlooked in debates over the ‘changing world of work’ is that today’s widespread use insecure and short term work is not new but represents a return to something more resembling labour markets in Australia, Europe and North America in the 19th and early 20th century. As this paper will seek to show, not only were precarious and exploitive working arrangements common during this period but the adverse effects of these on the health, safety and wellbeing was well documented in government inquiries, medical research, press reports and a variety of other sources. Drawing primarily on Australian and British sources, attention here will focus on casual labourers, sweated garment workers, the self-employed and merchant seamen. The paper highlights the valuable role historical research can play in shedding light on contemporary problems and policy debates.The symposium is organised on behalf of AAHANZBS by the Business and Labour History Group, The University of Sydney, with the financial support of the University’s Faculty of Economics and Business

Antioxidant therapeutic advances in COPD

Chronic obstructive pulmonary disease (COPD) is associated with a high incidence of morbidity and mortality. Cigarette smoke-induced oxidative stress is intimately associated with the progression and exacerbation of COPD and therefore targeting oxidative stress with antioxidants or boosting the endogenous levels of antioxidants is likely to have beneficial outcome in the treatment of COPD. Among the various antioxidants tried so far, thiol antioxidants and mucolytic agents, such as glutathione, N-acetyl-L-cysteine, N-acystelyn, erdosteine, fudosteine and carbocysteine; Nrf2 activators; and dietary polyphenols (curcumin, resveratrol, and green tea catechins/quercetin) have been reported to increase intracellular thiol status along with induction of GSH biosynthesis. Such an elevation in the thiol status in turn leads to detoxification of free radicals and oxidants as well as inhibition of ongoing inflammatory responses. In addition, specific spin traps, such as α-phenyl-N-tert-butyl nitrone, a catalytic antioxidant (ECSOD mimetic), porphyrins (AEOL 10150 and AEOL 10113), and a SOD mimetic M40419 have also been reported to inhibit cigarette smoke-induced inflammatory responses in vivo in the lung. Since a variety of oxidants, free radicals and aldehydes are implicated in the pathogenesis of COPD, it is possible that therapeutic administration of multiple antioxidants and mucolytics will be effective in management of COPD. However, a successful outcome will critically depend upon the choice of antioxidant therapy for a particular clinical phenotype of COPD, whose pathophysiology should be first properly understood. This article will review the various approaches adopted to enhance lung antioxidant levels, antioxidant therapeutic advances and recent past clinical trials of antioxidant compounds in COPD

The type of sugar moiety is a major determinant of the small intestinal uptake and subsequent biliary excretion of dietary quercetin glycosides.

Item does not contain fulltextQuercetin is an important dietary flavonoid with putative beneficial effects in the prevention of cancer and CVD. The in vivo bioactivity of quercetin depends on its bioavailability, which varies widely between foods. We used an in situ rat intestinal perfusion model to study whether differential small intestinal hydrolysis of the sugar moiety of five naturally occurring quercetin glycosides determines the small intestinal uptake and subsequent biliary excretion of quercetin. After 30 min perfusion, a decrease of intact quercetin glycoside in perfusate was observed for quercetin-3-O-ss-glucoside (20.9 (sem 1.4) micromol/l) and quercetin-4'-O-ss-glucoside (23.5 (sem 1.6) micromol/l), but not of quercetin-3-O-ss-galactoside, quercetin-3-O-ss-rhamnoside and quercetin-3-O-alpha-arabinopyranoside. Appearance of free quercetin in perfusate and conjugated quercetin metabolites (quercetin, isorhamnetin, and tamarixetin) in portal and peripheral plasma and bile were also significantly greater after treatment with quercetin-3-O-ss-glucoside or quercetin-4'-O-ss-glucoside compared with any of the other glycosides. Thus, the type of sugar moiety is a major determinant of the small intestinal absorption of quercetin glycosides, but the position (3 or 4') of the glucose moiety does not further influence absorption. The poor bioavailability of important dietary quercetin glycosides has implications for their in vivo bioactivities

Plasma enterolignans are associated with lower colorectal adenoma risk.

Item does not contain fulltextLignans are biphenolic compounds that occur in foods of plant origin such as whole grains, seeds, fruits and vegetables, and beverages, such as coffee and tea. Plant lignans are converted by intestinal bacteria into the enterolignans, enterodiol and enterolactone. Enterolignans possess several biological activities, whereby they may influence carcinogenesis. We studied the associations between plasma enterolignans and the risk of colorectal adenomas in a Dutch case-control study. Colorectal adenomas are considered to be precursors of colorectal cancer. Cases (n = 532) with at least one histologically confirmed colorectal adenoma and controls (n = 503) with no history of any type of adenoma were included. Plasma enterodiol and enterolactone concentrations were measured by liquid chromatography with tandem mass spectrometry. Associations were stronger for incident than for prevalent cases. When only incident cases (n = 262) were included, high compared to low plasma concentrations of enterodiol were associated with a reduction in colorectal adenoma risk after adjustment for confounding variables. Enterodiol odds ratios (95% confidence intervals) were 1.00, 0.69 (0.42-1.13), 0.60 (0.37-0.99), and 0.53 (0.32-0.88) with a significant trend (P = 0.01) through the quartiles. Although enterolactone plasma concentrations were 10-fold higher, enterolactone's reduction in risk was not statistically significant (P for trend = 0.09). Use of oral antibiotic therapy could decrease the plasma concentrations of enterolactone. Exclusion of antibiotic users resulted in similar odds ratios for both enterolignans, but the association for enterolactone became somewhat stronger (P = 0.05 versus P = 0.09). We observed a substantial reduction in colorectal adenoma risk among subjects with high plasma concentrations of enterolignans, in particular, enterodiol. These findings could be important in the prevention of colorectal adenomas

SIRT1 stimulation by polyphenols is affected by their stability and metabolism

Silent information regulator two ortholog 1 (SIRT1) is the human ortholog of the yeast sir2 protein; one of the most important regulators of lifespan extension by caloric restriction in several organisms. Dietary polyphenols, abundant in vegetables, fruits, cereals, wine and tea, were reported to stimulate the deacetylase activity of recombinant SIRT1 protein and could therefore be potential regulators of aging associated processes. However, inconsistent data between effects of polyphenols on the recombinant SIRT1 and on in vivo SIRT1, led us to investigate the influence of (1) stability of polyphenols under experimental conditions and (2) metabolism of polyphenols in human HT29 cells, on stimulation of SIRT1. With an improved SIRT1 deacetylation assay we found three new polyphenolic stimulators. Epigallocatechin galate (EGCg, 1.76-fold), epicatechin galate (ECg, 1.85-fold) and myricetin (3.19-fold) stimulated SIRT1 under stabilizing conditions, whereas without stabilization, these polyphenols strongly inhibited SIRT1, probably due to H2O2 formation. Using metabolically active HT29 cells we were able to show that quercetin (a stimulator of recombinant SIRT1) could not stimulate intracellular SIRT1. The major quercetin metabolite in humans, quercetin 3-O-glucuronide, slightly inhibited the recombinant SIRT1 activity which explains the lack of stimulatory action of quercetin in HT29 cells. This study shows that the stimulation of SIRT1 is strongly affected by polyphenol stability and metabolism, therefore extrapolation of in vitro SIRT1 stimulation results to physiological effects should be done with caution