The effects of weight loss on adipokines and markers of inflammation in dogs

Evidence suggests that adipose tissue-derived adipokines induce mild inflammation and may play a role in insulin resistance associated with diabetes. The present study was designed to examine a series of adipokines and markers of inflammation in dogs before and after a successful weight loss. The study included fasting serum samples from twenty-five dogs before and after a weight-loss programme. Serum C-reactive protein (CRP) and monocyte chemoattractant protein-1 (MCP-1) were measured as indicators of chronic inflammation, while serum adipokines including total adiponectin, high-molecular-weight (HMW) adiponectin, resistin and leptin were also examined. Medians for CRP (before, 10.0 (interquartile range 5.4-15.0) μg/ml; after, 5.6 (interquartile range 3.8-7.0) μg/ml) and MCP-1 (before, 212 (interquartile range 157-288) ng/ml; after, 185 (interquartile range 143-215) ng/ml) decreased significantly after weight loss. Medians for resistin showed a mild, yet significant reduction (before, 67.1 (interquartile range 44.4-88.5) pg/ml; after, 60.5 (interquartile range 32.3-67.1) pg/ml), while leptin showed a dramatic decrease after weight loss (before, 18.9 (interquartile range 10.8-35.4) ng/ml; after, 6.6 (interquartile range 3.9-10.2) ng/ml). Serum total adiponectin and HMW adiponectin were unchanged on all analyses performed. These data suggest that weight loss can decrease chronic inflammation; however, the clinical implications of this decrease are not well elucidated in dogs. Surprisingly, there was no increase in total or HMW serum adiponectin after weight loss, as observed previously in human subjects. The lack of change in total and HMW adiponectin might explain why insulin resistance and type 2 diabetes are less prevalent in obese dogs when compared with humans and cats.     

Increased lean red meat intake does not elevate markers of oxidative stress and inflammation in humans

Red meat intake has been associated with increased risk of coronary heart disease and type 2 diabetes, but it remains uncertain whether these associations are causally related to unprocessed lean red meat. It has been proposed that iron derived from red meat may increase iron stores and initiate oxidative damage and inflammation. We aimed to determine whether an increase in unprocessed lean red meat intake, partially replacing carbohydrate-rich foods, adversely influences markers of oxidative stress and inflammation. Sixty participants completed an 8-wk parallel-designed study. They were randomized to maintain their usual diet (control) or to partially replace energy from carbohydrate-rich foods with approximately 200 g/d of lean red meat (red meat) in isoenergetic diets. Markers of oxidative stress and inflammation were measured at baseline and at the end of intervention. Results are presented as the mean between-group difference in change and [95% CI]. Red meat, relative to control, resulted in: higher protein [5.3 (3.7, 6.9) % of energy], lower carbohydrate [-5.3 (-7.9, -2.7)% of energy], and higher iron [3.2 (1.1, 5.4) mg/d] intakes; lower urinary F2-isoprostane excretion [-137 (-264, -9) pmol/mmol creatinine], lower leukocyte [-0.51 (-0.99, -0.02)x10(9)/L] counts, and a trend for lower serum C-reactive protein concentrations [-1.6 (-3.3, 0.0) mg/L, P=0.06]; and no differences in concentrations of plasma F2-isoprostanes [-12 (-122, 100) pmol/L], serum gamma-glytamyltransferase [-0.8 (-3.2, 1.5) U/L], serum amyloid A protein [-1.4 (-3.4, 0.5) mg/L], and plasma fibrinogen concentrations [-0.08 (-0.40. 0.24) g/L]. Our results suggest that partial replacement of dietary carbohydrate with protein from lean red meat does not elevate oxidative stress or inflammation.     

A high intake of trans fatty acids has little effect on markers of inflammation and oxidative stress in humans

Consumption of industrial trans fatty acids (iTFA) increases LDL cholesterol, decreases HDL cholesterol, and is strongly associated with a higher risk of cardiovascular disease (CVD). However, changes in circulating cholesterol cannot explain the entire effect. Therefore, we studied whether iTFA and conjugated linoleic acid (CLA) affect markers of inflammation and oxidative stress. Sixty-one healthy adults consumed each of 3 diets for 3 wk, in random order. Diets were identical except for 7% of energy provided by oleic acid (control diet), iTFA, or CLA. At the end of the 3 wk, we measured plasma inflammatory markers IL-6, C-reactive protein, tumor necrosis factor receptors I and II (TNF-RI and -RII), monocyte chemotactic protein-1 and E-selectin, and urinary 8-iso-PGF(2α), a marker of lipid peroxidation. Consumption of iTFA caused 4% lower TNF-RI concentrations and 6% higher E-selectin concentrations compared with oleic acid (control) and had no significant effect on other inflammatory markers. CLA did not significantly affect inflammatory markers. The urine concentration of 8-iso-PGF(2α) [geometric mean (95% CI)] was greater after the iTFA [0.54 (0.48, 0.60) nmol/mmol creatinine] and the CLA [1.2 (1.1, 1.3) nmol/mmol creatinine] diet periods than after the control period [0.45 (0.41, 0.50) nmol/mmol creatinine; P < 0.05]. In conclusion, high intakes of iTFA and CLA did not substantially affect plasma concentrations of inflammatory markers, but they increased the urine 8-iso-PGF(2α) concentration. However, it is unlikely this plays a major role in the mechanism by which iTFA increase the risk of CVD. However, more research is needed to fully understand the implications of these findings.     

Bioactive compounds: Safety and efficacy

The efficacy and safety of bioactive compounds depend on a few known and unknown parameters. What is a physiologic dose and how can that dose be defined in cases of bioactive compounds with a poor knowledge of supply and distribution? What safety sets are needed? How can individual aspects such as polymorphisms or differences in absorption be considered? A group of experts tried to answer these and related questions during the 23rd Hohenheim Consensus Meeting at the University of Hohenheim in Stuttgart.     

Bioactive compounds in berries relevant to human health

Berries contain powerful antioxidants, potential allergens, and other bioactive compounds. Genetic and environmental factors affect production and storage of such compounds. For this reason breeding and biotechnological approaches are currently used to control or to increase the content of specific health-related compounds in fruits. This work reviews the main bioactive compounds determining the nutritional quality of berries, the major factors affecting their content and activity, and the genetic options currently available to achieve new genotypes able to provide, under controlled cultivation conditions, berries with the proper balance of bioactive compounds for improving consumer health.     

Short-term effects of air temperature on blood markers of coagulation and inflammation in potentially susceptible individuals

Objectives Changes in air temperature are associated with an increase in cardiovascular events, but the role of procoagulant and proinflammatory blood markers is still poorly understood. The authors investigated the association between air temperature and fibrinogen, plasminogen activator inhibitor type 1, interleukin-6 and high-sensitivity C reactive protein in two potentially susceptible groups. Methods This prospective panel study was conducted between March 2007 and December 2008 in Augsburg, Germany. The study population comprised 187 participants with type 2 diabetes mellitus or impaired glucose tolerance and 87 participants with genetic polymorphisms on the detoxification and inflammation pathways. Overall, 1766 repeated blood measurements were collected. Hourly meteorology data were available from a central measurement site. The association between temperature and blood markers was analysed with additive mixed models. Results For type 2 diabetes mellitus and impaired glucose tolerance participants, the authors observed immediate, lagged and cumulative increases in fibrinogen (range of percentage changes in geometric mean: 0.6%-0.8%) and plasminogen activator inhibitor type 1 (6.0%-10.1%) in association with a 5°C temperature decrement. Participants with a body mass index above 30 kg/m(2) as well as females showed particularly strong fibrinogen effects. In participants with the special genetic background, 5°C decreases in the 5-day average of temperature led to a change of 8.0% (95% CI 0.5% to 16.2%) in interleukin-6 and of -8.4% (95% CI -15.8% to -0.3%) in high-sensitivity C reactive protein, the latter driven by physically active individuals. Conclusions The authors observed different temperature effects on blood markers in two potentially susceptible groups probably indicating varying underlying biological mechanisms. This study results might provide a link between temperature and cardiovascular events.     

Effect of sucrose on inflammatory markers in overweight humans

BACKGROUND: Observational studies have found that dietary glycemic load is positively associated with C-reactive protein (CRP) concentrations in healthy humans, which suggests that the type of carbohydrate ingested influences inflammatory activity. OBJECTIVE: We investigated the effect of a diet with a high content of sucrose or artificial sweeteners on the inflammatory markers CRP, haptoglobin, and transferrin in overweight subjects. DESIGN: Overweight men and women consumed daily food and drink supplements containing either sucrose [n = 21; body mass index (BMI, in kg/m2): 28.0] or artificial sweeteners (n = 20; BMI: 27.6), predominantly from soft drinks (70%; average approximately 1.3 L/d) for 10 wk. RESULTS: During the intervention, sucrose intake increased by 151% in the sucrose group and decreased by 42% in the sweetener group, resulting in a 1.6-kg weight gain in the sucrose group and a 1.2-kg weight loss in the sweetener group over 10 wk (P < 0.001). Concentrations of haptoglobin, transferrin, and CRP increased by 13%, 5%, and 6%, respectively, in the sucrose group and decreased by 16%, 2%, and 26%, respectively, in the sweetener group (between-group differences: P = 0.006, P = 0.01, and P = 0.1, respectively). Adjustment for changes in body weight and energy intake did not substantially influence this outcome. CONCLUSIONS: The study shows that in the present group of overweight subjects a high consumption of sugar-sweetened foods and drinks increased haptoglobin and transferrin but had, at best, only a limited influence on CRP.     

Foods with different satiating effects in humans

The aim of this study was to identify particular properties of foods that can affect satiety. Two levels (50 and 200 kcal) of three preloads (tomato soup, melon, cheese on crackers) were given just before two different second courses (macaroni and beef casserole, grilled cheese sandwiches), allowing us to examine the effects of caloric level, energy density, and sensory-specific satiety on food intake in normal weight, non-dieting males. Eating time and initial palatability ratings were held constant. Soup was found to reduce second course intake significantly more than the other preloads. This reduction could be partially accounted for by the low energy density of tomato soup; however, soup reduced intake more than the melon preload, which was matched for energy density. Sensory-specific satiety did not explain the satiating efficiency of the soup. Thus, during a meal, tomato soup is more satiating than the melon and cheese on crackers. Further studies are required to determine why these foods have different effects and to determine whether soup consumption can be beneficial in weight reduction programs.     

Neurochemical markers of alcoholism vulnerability in humans

This review considers several neurochemical characteristics or trait markers that may be related to a genetic vulnerability to alcoholism. These potential neurochemical markers of alcoholism vulnerability include indices of activity of five neurotransmitter systems, namely gamma-aminobutyric acid, serotonin, dopamine, noradrenaline and beta-endorphin. This review evaluates whether potential abnormalities in these neurochemical indices, as assessed in alcoholics and in the children of alcoholics, meet three criteria for the identification of a vulnerability marker of alcoholism: (1). heritable; (2). associated with alcoholism in the general population; (3). state independent. It is concluded that, at present, indices of increased baseline activity of the serotonin transporter in platelets and of increased responsiveness of the pituitary beta-endorphin system may fulfil each of these three criteria. Additional research efforts should be devoted to the evaluation of trait marker properties of neurochemical indices in individuals at high risk for alcoholism.     

Bioavailability and antioxidant effects of olive oil phenolic compounds in humans: a review

Olive oil, the main source of fat in the Mediterranean diet, is a functional food which besides having a high level of monounsaturated fatty acid contains several minor components with biological properties. For some olive oil minor components, such as the antioxidant phenolic compounds, a large body of studies, mainly experimental or in animal models, have been performed. Randomized, controlled, clinical trials in humans are required to provide evidence that olive phenolic compounds contribute significantly to health benefits in order to give recommendations at population level. Here, we summarize the state of the art of the body of knowledge, and to which extent we have evidence, of the bioavailability and of the antioxidant benefits of olive oil phenolic compounds in humans.     

Bioactive compounds: Definition and assessment of activity

Biomarkers and their role in evaluating efficacy and safety were the topic of the 23rd Hohenheim Consensus Meeting at the University of Hohenheim in Stuttgart. Scientists who had published and reviewed scientific and regulatory papers on the topic were invited, among them basic researchers, toxicologists, clinicians, and nutritionists. The participants were presented with 11 questions (in bold font), which were discussed and answered (in italic font) at the workshop, with the aim of summarizing the current state of knowledge on the subject. The explicatory text accompanying the short answers was produced and agreed on after the conference and was backed up by corresponding references.     

Dietary micronutrient intakes are associated with markers of inflammation but not with markers of subclinical atherosclerosis

Few studies have examined associations of dietary micronutrients with markers of inflammation and subclinical atherosclerosis. The present study investigated associations of heme iron, nonheme iron, zinc (Zn), magnesium (Mg), β-carotene, vitamin C, and vitamin E with C-reactive protein (CRP), IL-6, total homocysteine (tHcy), fibrinogen, coronary artery calcium, and common and internal carotid artery intima media thickness. Micronutrient intakes and markers of inflammation and subclinical atherosclerosis were studied in 5,181 participants from the Multi-Ethnic Study of Atherosclerosis who were aged 45-84 y and free of diabetes and cardiovascular disease. Models were adjusted for energy intake, demographics, lifestyle characteristics, and BMI. Dietary nonheme iron and Mg intakes were inversely associated with tHcy concentrations (mean tHcy: 9.11, 8.86, 8.74, 8.71, and 8.50 μmol/L, and 9.20, 9.00, 8.65, 8.76, and 8.33 μmol/L across increasing quintiles of nonheme iron and Mg, respectively; P-trend < 0.001 for both). However, dietary Zn and heme iron were positively associated with CRP [mean: 1.73, 1.75, 1.78, 1.88, and 1.96 mg/L across increasing quintiles of Zn and 1.72, 1.76, 1.83, 1.86, and 1.94 mg/L across increasing quintiles of heme iron (P-trend = 0.002 and 0.01, respectively). Other tested micronutrient-marker associations were not significant. In conclusion, of the 49 tested associations, only 7 were significant. Although this study does not provide strong support for associations between the micronutrients and markers of inflammation and subclinical atherosclerosis, the results are consistent with dietary guidelines that advocate for a balanced diet that includes a variety of plant foods containing Mg, Zn, and nonheme iron.     

Bioactive compounds in different citrus varieties. Discrimination among cultivars

Cultivars of Clementine mandarin (Arrufatina, Clemenpons, Clemenules, Fino, Hernandina Loretina, Marisol, Orogrande, Oronules and Oroval), Satsume mandarin (Avasa Pri-10, Avasa Pri-19, Okitsu and Owari), Hybrid mandarin (Fortune, Ortanique and Nova), Navel orange (Fukumoto, Lanelate, Navelate, Navelina, Navel Foyos, Newhall and Powell), Common orange (Salustiana and Valencia Late) and Pigmented orange (Sanguinelli) groups have been analysed for its content in narirutin, hesperidin and total vitamin C. Sweet orange groups presented the higher concentration in flavonoids and total vitamin C. The influence of variety on the content of bioactive constituents and its contribution to taxonomy at the varietal level is studied.     

Effect of a wild blueberry (Vaccinium angustifolium) drink intervention on markers of oxidative stress, inflammation and endothelial function in humans with cardiovascular risk factors

Purpose

Wild blueberries (WB) (Vaccinium angustifolium) are rich sources of polyphenols, such as flavonols, phenolic acids and anthocyanins (ACNs), reported to decrease the risk of cardiovascular and degenerative diseases. This study investigated the effect of regular consumption of a WB or a placebo (PL) drink on markers of oxidative stress, inflammation and endothelial function in subjects with risk factors for cardiovascular disease.

Methods

Eighteen male volunteers (ages 47.8 ± 9.7 years; body mass index 24.8 ± 2.6 kg/m²) received according to a cross-over design, a WB (25 g freeze-dried powder, providing 375 mg of ACNs) or a PL drink for 6 weeks, spaced by a 6-week wash-out. Endogenous and oxidatively induced DNA damage in blood mononuclear cells, serum interleukin levels, reactive hyperemia index, nitric oxide, soluble vascular adhesion molecule concentration and other variables were analyzed.

Results

Wild blueberry drink intake significantly reduced the levels of endogenously oxidized DNA bases (from 12.5 ± 5.6 % to 9.6 ± 3.5 %, p ≤ 0.01) and the levels of H₂O₂-induced DNA damage (from 45.8 ± 7.9 % to 37.2 ± 9.1 %, p ≤ 0.01), while no effect was found after the PL drink. No significant differences were detected for markers of endothelial function and the other variables under study.

Conclusions

In conclusion, the consumption of the WB drink for 6 weeks significantly reduced the levels of oxidized DNA bases and increased the resistance to oxidatively induced DNA damage. Future studies should address in greater detail the role of WB in endothelial function. This study was registered at www.isrctn.org as ISRCTN47732406.     

Effect of whole grains on markers of subclinical inflammation

The reduction of subclinical inflammation has been suggested as a potential mechanism to explain the favorable association between whole-grain consumption and reduced risk for cardiovascular disease, diabetes, and certain cancers. This review examines evidence for the effects of whole-grain consumption on markers of subclinical inflammation derived from 13 epidemiological and 5 interventional studies retrieved from a search of the PubMed database. Epidemiological studies provide reasonable support for an association between diets high in whole grains and lower C-reactive protein (CRP) concentrations. After adjusting for other dietary factors, each serving of whole grains is estimated to reduce CRP concentrations by approximately 7%. In contrast to epidemiological studies, interventional studies do not demonstrate a clear effect of increased whole-grain consumption on CRP or other markers of inflammation. Issues related to insufficient length of intervention, extent of dietary control, population selection, types of whole grains, and lack of a direct anti-inflammatory effect may underlie these discrepant findings. Additional carefully controlled interventional studies are needed to clarify the effects of whole grains on subclinical inflammation.     

Serum carotenoids and markers of inflammation in nonsmokers

One explanation for discrepant results between epidemiologic studies and randomized trials of beta-carotene and cardiovascular disease may be a failure to consider inflammation as a confounder. To evaluate the potential for such confounding, the authors relate the serum concentrations of five carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin) to levels of three inflammatory markers (C-reactive protein, fibrinogen, and white blood cell count) measured during the Third National Health and Nutrition Survey, 1988-1994. The analysis included 4,557 nonsmoking participants aged 25-55 years. Adjusted concentrations of all five carotenoids were significantly lower in those with C-reactive protein levels above 0.88 mg/dl (p = 0.001). There was a trend toward lower adjusted beta-cryptoxanthin concentrations with increasing level of fibrinogen (p value test for trend = 0.01), but other carotenoids were not related. Many of the carotenoid concentrations were lower among participants with high white blood cell counts. After log transformation, only adjusted mean beta-carotene levels were significantly lower in those with white blood cell counts above 7.85 x 10(9)/liter (p < 0.01). These cross-sectional data do not clarify the biologic relation between carotenoids and C-reactive protein but, to the extent that the carotenoids are associated with C-reactive protein levels, a carotenoid-heart disease association may be, in part, an inflammation-heart disease association.     

Bioactive compounds from regular diet and faecal microbial metabolites

European Journal of Nutrition - Short-chain fatty acids (SCFAs) formation by intestinal bacteria is regulated by many different factors, among which dietary fibre is currently receiving most...     

Argan oil improves surrogate markers of CVD in humans

Limited - though increasing - evidence suggests that argan oil might be endowed with potential healthful properties, mostly in the areas of CVD and prostate cancer. We sought to comprehensively determine the effects of argan oil supplementation on the plasma lipid profile and antioxidant status of a group of healthy Algerian subjects, compared with matched controls. A total of twenty healthy subjects consumed 15 g/d of argan oil - with toasted bread - for breakfast, during 4 weeks (intervention group), whereas twenty matched controls followed their habitual diet, but did not consume argan oil. The study lasted 30 d. At the end of the study, argan oil-supplemented subjects exhibited higher plasma vitamin E concentrations, lower total and LDL-cholesterol, lower TAG and improved plasma and cellular antioxidant profile, when compared with controls. In conclusion, we showed that Algerian argan oil is able to positively modulate some surrogate markers of CVD, through mechanisms which warrant further investigation.     

Identification of gene markers for formaldehyde exposure in humans

BACKGROUND: Formaldehyde (FA) is classified as a human carcinogen and has been linked to increased leukemia rates in some epidemiologic studies. Inhalation of FA induces sensory irritation at relatively low concentrations. However, little is known concerning the cellular alterations observed after FA exposure in humans. OBJECTIVES: Our aim was to profile global gene expression in Hs 680.Tr human tracheal fibroblasts exposed to FA and to develop biomarkers for the evaluation of FA exposure in humans. METHODS AND RESULTS: We used gene expression analysis, and identified 54 genes designated as FA responsive. On the basis of these data, we conducted an exploratory analysis of the expression of these genes in human subjects exposed to high or low levels of FA. We monitored FA exposure by measuring the urinary concentration of thiazolidine-4-carboxylate (TZCA), a stable and quantitative cysteinyl adduct of FA. Nine genes were selected for real-time PCR analysis; of these, BHLHB2, CCNL1, SE20-4, C8FW, PLK2, and SGK showed elevated expression in subjects with high concentrations of TZCA. CONCLUSION: The identification of gene marker candidates in vitro using microarray analysis and their validation using human samples obtained from exposed subjects is a good tool for discovering genes of potential mechanistic interest and biomarkers of exposure. Thus, these genes are differentially expressed in response to FA and are potential effect biomarkers of FA exposure.