Epidemiological and animal studies have shown that dietary fiber is protective against the development of colon cancer. Dietary fiber is a rich source of the hydroxycinnamic acids ferulic acid (FA) ...and p-coumaric acid (p-CA), which both may contribute to the protective effect. We have investigated the effects of FA and p-CA treatment on global gene expression in Caco-2 colon cancer cells. The Caco-2 cells were treated with 150 μM FA or p-CA for 24 h, and gene expression was analyzed with cDNA microarray technique. A total of 517 genes were significantly affected by FA and 901 by p-CA. As we previously have found that FA or p-CA treatment delayed cell cycle progression, we focused on genes involved in proliferation and cell cycle regulation. The expressions of a number of genes involved in centrosome assembly, such as RABGAP1 and CEP2, were upregulated by FA treatment as well as the gene for the S phase checkpoint protein SMC1L1. p-CA treatment upregulated CDKN1A expression and downregulated CCNA2, CCNB1, MYC, and ODC1. Some proteins corresponding to the affected genes were also studied. Taken together, the changes found can partly explain the effects of FA or p-CA treatment on cell cycle progression, specifically in the S phase by FA and G
2
/M phase by p-CA treatment.
Recently, a group of betainized compounds have been suggested to play a role in health effects in relation to a whole-grain-rich diet.
The aims of this study were to develop a quantitative mass ...spectrometric method for selected betainized compounds in human plasma, and to investigate their association with nutrient intake and measures of metabolic health in participants of the SYSDIET study.
The SYSDIET study was a controlled randomized intervention including individuals with metabolic syndrome, where the healthy Nordic diet (HND) group increased intakes of whole grains, canola oil, berries, and fish, whereas the control diet (CD) group consumed low-fiber cereal products, milk fat, and restricted amounts of fish and berries. A quantitative LC combined with triple quadrupole MS method for betainized compounds was developed and applied to fasting plasma samples from baseline (week 0) and the end of the intervention (week 18 or 24). Concentrations of betainized compounds were correlated with intakes of selected nutrients and fiber and measures of metabolic health.
Pipecolic acid betaine (PAB) concentrations were significantly higher in the HND group than in the CD group (P = 0.00032) at the end of the intervention and correlated directly (P < 0.0001) with intakes of dietary fiber (r = 0.376) and a biomarker related to whole-grain rye intake, namely the ratio of alkylresorcinol C17:0 to C21:0 (r = 0.442). PAB was associated inversely with fasting plasma insulin consistently at the beginning and at the end of the intervention (P < 0.001, r = −0.300; P < 0.01, r = −0.250, respectively), as well as IL-1 receptor antagonist (P < 0.01, r = −0.232 at the beginning; P < 0.01, r = −0.236 at the end) and serum LDL/HDL cholesterol (P < 0.01, r = −0.239 at the beginning; P < 0.01, r = −0.241 at the end).
Among adults with the metabolic syndrome, PAB plasma concentrations were associated with fasting insulin, inflammation, and lipids and were significantly increased with adoption of the HND. Further studies are needed to clarify the biological functions of betainized compounds. This trial was registered at clinicaltrials.gov as NCT00992641.
The present review examines the evidence regarding the effect of β‐glucan on variables linked to the metabolic syndrome (MetS), including appetite control, glucose control, hypertension, and gut ...microbiota composition. Appetite control can indirectly influence MetS by inducing a decreased energy intake, and promising results for a β‐glucan intake to decrease appetite have been found using gut hormone responses and subjective appetite indicators. Beta‐glucan also improves the glycemic index of meals and beneficially influences glucose metabolism in patients with type 2 diabetes or MetS, as well as in healthy subjects. Furthermore, a blood‐pressure‐lowering effect of β‐glucan in hypertensive subjects seems fairly well substantiated. The gut microbiota composition might be an interesting target to prevent MetS, and preliminary results indicate the prebiotic potential of β‐glucan. The evidence that β‐glucan influences appetite control and gut microbiota in a positive way is still insufficient or difficult to interpret, and additional studies are needed in this field. Still, much evidence indicates that increased β‐glucan intake could prevent MetS. Such evidence should encourage increased efforts toward the development of β‐glucan‐containing functional foods and promote the intake of β‐glucan‐rich foods, with the aim of reducing healthcare costs and disease prevalence.
Background The relationship between selenium and cancer involves many different aspects. These include the forms of selenium present in the diet and in the body, their functions and mechanisms of ...action, and methods employed in assessing an individual's selenium nutritional status--both in general, and in epidemiological studies of the risk of cancer in relation to diet, as well as in connection with long-term trials for investigating the disease-preventive potential of selenium supplementation. Aim of the review To review different aspects on selenium metabolism, the occurrence of different selenoproteins and their use as biomarkers of selenium status, the results of intervention trials of the cancer-preventive effects of selenium supplementation, the mechanisms of action involved, together with epidemiological findings on relations between the selenium status in the body and risk of cancer. Results and conclusions The rapid advance in the knowledge of different selenoproteins and their biological functions has opened up new possibilities for the understanding of the biological effects of selenium supplementation. A wide variety of effects of different forms and doses of selenium has been observed in a number of experimental systems, and it is at present difficult to pinpoint the mechanism that may explain the positive preventive effects of selenium supplementation observed in some human long-term trials. Moreover, additional such trials are needed to define the benefits and risks of different types and doses of selenium supplements which in the future may be implemented for public health reasons. Another necessary focus for future research is a better understanding of the mechanisms by which selenium interferes with the carcinogenesis process.
Bioactive compounds were investigated in genotypes (cauliflower 10, white cabbage 10, curly kale 1) and plant parts of the three crops. The content of most of the major glucosinolates glucobrassicin, ...sinigrin and glucoiberin differed significantly between cultivars. Samples harvested in 2000 had higher amounts of several glucosinolates than samples from 1999. Within cauliflower the buds of the floret had 1.5 to 2.5-fold higher concentration of glucobrassicin and 4-methoxyglucobrassicin than the stalk. In white cabbage several glucosinolates had their highest content in the outer leaves (up to 2-fold higher). Upper leaves of curly kale contained 5-fold more of total glucosinolates than lower leaves. Chlorogenic acid was the dominating hydroxycinnamate in curly kale, which also contained at least ten times more of carotenoids (mainly lutein) than white cabbage. Total antioxidant capacity (TAC) assayed with the FRAP method was 0.76 (0.06) micromole/g fw (mean (SD)) in water-soluble and 0.32 (0.04) in water-insoluble extracts of cauliflower which was 62-68% higher than in white cabbage. Curly kale contained 6.4 and 6.1 micromol/g fw TAC in water-soluble and water-insoluble extracts. TAC did not differ between plant parts. Progoitrin and 4-hydroxyglucobrassicin were correlated to water-soluble TAC in white cabbage, probably reflecting a variation in other compounds. Cauliflower contained less glucose, fructose and sorbitol but more sucrose than white cabbage. Curly kale had lower contents of glucose (approximately 2 times), fructose (approximately 4-5 times) and sucrose (20 and 36 times, respectively) than cauliflower and white cabbage, while inositol was only found in curly kale. Storage of white cabbage reduced the amount of sorbitol and sucrose. The study shows that cultivar, plant part and storage affect the content of bioactive compounds in Brassica vegetables. The variation between years, as in cauliflower, is due to environmental factors. Since the cultivar ranking order was rather stable for several components the data could provide a basis for the selection of cultivars optimised for valuable health components for fresh market consumption.
Biomarkers of dietary intake can be important tools in nutrition research. Our aim was to assess whether plasma alkylresorcinol (AR) and β-carotene concentrations could be used as dietary biomarkers ...for whole-grain, fruits and vegetables in a healthy Nordic diet (ND). Participants (n = 166), 30–65 y with a body mass index of 27–40 kg/m2 and two more features of metabolic syndrome (International Diabetes Federation definition, slightly modified), were recruited through six centers in the Nordic countries and randomly assigned to an ND or control diet for 18 or 24 wk, depending on study center. Plasma AR and β-carotene were analyzed and nutrient intake calculated from 4-d food records. Median fiber intake increased in the ND group from 2.5 g/MJ at baseline to 4.1 g/MJ (P < 0.001) at end point (week 18 or 24), and median (IQR) fasting plasma total AR concentration increased from 73 (88) to 106 (108) nmol/L, or 45%, from baseline to end point (P < 0.001). The AR concentration was significantly higher in the ND group (P < 0.001) than in the control group at end point. β-Carotene intake tended to increase in the ND group (P = 0.07), but the plasma β-carotene concentration did not change significantly throughout the study and did not differ between the groups at follow-up. In conclusion, an ND resulted in higher dietary fiber intake and increased plasma total AR concentration compared with the control diet, showing that the total AR concentration might be a valid biomarker for an ND in which whole-grain wheat and rye are important components. No significant difference in plasma β-carotene concentrations was observed between the ND and control groups, suggesting that β-carotene may not be a sensitive enough biomarker of the ND.
Selenium is essential for maintaining many body functions through the actions of selenoproteins. To find factors regulating selenoprotein biosynthesis in the bovine mammary cell line MAC-T, the ...effects of supplementation with selenite and also with retinoic acid, insulin, hydrocortisone and prolactin on the mRNA expression of a number of selenoproteins were investigated. It was found that MAC-T cells express glutathione peroxidase (GPx) 1 and 4, thioredoxin reductase 1 and selenoprotein P, but not GPx 3, which is interesting considering that GPx 3 is one of the only few selenoproteins detected in milk so far. Addition of selenite to the cell culture resulted in a large increase in GPx 1 expression and an increase in selenoprotein P expression, which is similar to the findings made in other systems investigated. Increased mRNA levels of GPx 1 were also observed in cells treated with insulin and hydrocortisone or with retinoic acid. The expression of thioredoxin reductase 1 was increased in cells treated with retinoic acid, whereas that of selenoprotein P was decreased in cells exposed to insulin. The results indicate that several hormones, selenium, and retinoic acid regulate the biosynthesis of various selenoproteins differently in the bovine mammary cell. The possible implications of the findings for processes related to milk formation and mammary carcinogenesis will need additional investigation. Further study of the detailed mechanisms involved is also necessary.
Abstract
The effect of antioxidant supplementation on biomarkers of oxidative stress was investigated in a 6-week intervention study in 60 overweight men. The supplement contained a combination of ...antioxidants aiming to correspond to the antioxidant content found in a diet rich in fruit and vegetables. Placebo, single or double dose of antioxidants was provided to the subjects. Metabolic variables, plasma antioxidants and biomarkers of oxidative stress (lipid peroxidation and DNA damage) were measured. No effect of supplementation on biomarkers of oxidative stress was observed. Both intervention groups showed substantial increases of plasma antioxidants. This study demonstrated that supplementation with a combination of antioxidants did not affect lipid peroxidation and DNA damage in overweight men, despite increased concentrations of plasma antioxidants. The absence of antioxidant supplement effect might possibly be explained by the chosen study group having a normal level of oxidative stress, duration of the intervention and/or doses of antioxidants.
Abstract Cutaneous leishmaniasis triggers a varied immune response depending on parasite and host factors, which in turn can be influenced by nutrients. The resistance to the infection is associated ...with the Th1 type of cytokine production. The Th1 type can be reduced as a consequence of zinc deficiency, which may increase the risk for chronicity of the infection. Using in vitro and ex vivo models, we studied the influence of zinc supplementation on the immune response in patients with cutaneous leishmaniasis treated with antimony and the data were also compared to those of matched controls. Twenty-nine patients with cutaneous leishmaniasis ( n = 14 in zinc-supplemented group 45 mg/day and n = 15 in placebo group) were treated by intramuscular injections of antimony for 20 days and took supplements for 60 days. Immunoglobulins in plasma and cell proliferation, IFN-γ production and CD markers of isolated peripheral blood mononuclear cells (PBMC) were measured. It was found that the cellular immune response of the patients maintained its activity as assessed by the ability of the PBMC to proliferate and produce IFN-γ in response to concanavalin A. Moreover, there was no difference in these variables between the zinc-supplemented and placebo groups after 60 days. The addition of zinc sulphate in vitro to PBMC reduced the IFN-γ production in the placebo group only. It is concluded that the cellular immune response of the cutaneous leishmaniasis patients remained active during treatment by antimony when compared to that of controls. It was not possible to document an additional effect of zinc supplementation for 60 days on the immune response.
The role of micronutrient status for the incidence and clinical course of cutaneous leishmaniasis is not much studied. Still zinc supplementation in leishmaniasis has shown some effect on the ...clinical recovery, but the evidence in humans is limited.
To compare biochemical nutritional status in cutaneous leishmaniasis patients with that in controls and to study the effects of zinc supplementation for 60 days.
Twenty-nine patients with cutaneous leishmaniasis were treated with antimony for 20 days. Fourteen of them got 45 mg zinc daily and 15 of them got placebo. Biomarkers of nutritional and inflammatory status and changes in size and characteristics of skin lesions were measured.
The level of transferrin receptor was higher in patients than in controls but otherwise no differences in nutritional status were found between patients and controls. No significant effects of zinc supplementation on the clinical recovery were observed as assessed by lesion area reduction and characteristics or on biochemical parameters.
It is concluded that nutritional status was essentially unaffected in cutaneous leishmaniasis and that oral zinc supplementation administered together with intramuscular injection of antimony had no additional clinical benefit.
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