Avenanthramides, polyphenols from oats, exhibit anti-inflammatory and anti-itch activity

Adaptive cellular stress pathways as therapeutic targets of dietary phytochemicals: focus on the nervous system

During the past 5 decades, it has been widely promulgated that the chemicals in plants that are good for health act as direct scavengers of free radicals. Here we review evidence that favors a different hypothesis for the health benefits of plant consumption, namely, that some phytochemicals exert disease-preventive and therapeutic actions by engaging one or more adaptive cellular response pathways in cells. The evolutionary basis for the latter mechanism is grounded in the fact that plants produce natural antifeedant/noxious chemicals that discourage insects and other organisms from eating them. However, in the amounts typically consumed by humans, the phytochemicals activate one or more conserved adaptive cellular stress response pathways and thereby enhance the ability of cells to resist injury and disease. Examplesof such pathways include those involving the transcription factors nuclear factor erythroid 2-related factor 2, nuclear factor-κB, hypoxia-inducible factor 1α, peroxisome proliferator-activated receptor γ, and forkhead box subgroup O, as well as the production and action of trophic factors and hormones. Translational research to develop interventions that target these pathways may lead to new classes of therapeutic agents that act by stimulating adaptive stress response pathways to bolster endogenous defenses against tissue injury and disease. Because neurons are particularly sensitive to potentially noxious phytochemicals, we focus on the nervous system but also include findings from other cell types in which actions of phytochemicals on specific signal transduction pathways have been more thoroughly studied.

Evaluation of the bioactive properties of avenanthramide analogs produced in recombinant yeast

Saccharomyces cerevisiae has been proven to be a valuable tool for the expression of plant metabolic pathways. By engineering a S. cerevisiae strain with two plant genes (4cl-2 from tobacco and hct from globe artichoke) we previously set up a system for the production of two novel phenolic compounds, N-(E)-p-coumaroyl-3-hydroxyanthranilic acid (Yeast avenanthramide I, Yav I) and N-(E)-caffeoyl-3-hydroxyanthranilic acid (Yeast avenanthramide II, Yav II). These compounds have a structural similarity with a class of bioactive oat compounds called avenanthramides. By developing a fermentation process for the engineered S. cerevisiae strain, we obtained a high-yield production of Yav I and Yav II. To examine the biological relevance of these compounds, we tested their potential antioxidant and antiproliferative properties upon treatment of widely used cell models, including immortalized mouse embryonic fibroblast cell lines and HeLa cancer cells. The outcomes of our experiments showed that both Yav I and Yav II enter the cell and trigger a significant up-regulation of master regulators of cell antioxidant responses, including the major antioxidant protein SOD2 and its transcriptional regulator FoxO1 as well as the down-regulation of Cyclin D1. Intriguingly, these effects were also demonstrated in cellular models of the human genetic disease Cerebral Cavernous Malformation, suggesting that the novel phenolic compounds Yav I and Yav II are endowed with bioactive properties relevant to biomedical applications. Taken together, our data demonstrate the feasibility of biotechnological production of yeast avenanthramides and underline a biologically relevant antioxidant activity of these molecules.

Current topical and systemic therapies for itch

Itch is a common distressing symptom which may be caused by multifactorial aetiologies including inflammatory skin diseases, systemic diseases, neuropathic conditions and psychogenic disorders. Itch is a term used synonymously with pruritus and is defined as acute if it lasts less than 6 weeks or chronic if it persists for more than 6 weeks. It can have the same impact on the quality of life as chronic pain and shares many of the same pathophysiological pathways. Depending on the aetiology of the itch, different pathogenic mechanisms have been postulated with a number of mediators identified. These include histamine, leukotrienes, proteases, neuropeptides, cytokines and opioids, which may activate peripheral itch-mediating C-fibres via receptors on the nerve terminals and central neuronal pathways. Therefore, there is no single universally effective anti-itch treatment available. First-line treatments for itch include topical therapies, such as emollients, mild cleansers (low pH), topical anaesthetics, steroids, calcineurin inhibitors and coolants (menthol). Treatment with systemic therapies can vary according to the aetiology of the chronic itch. Non-sedating antihistamines are helpful in conditions such as urticaria where the itch is primarily histamine mediated. Although the itch of eczema is not mediated by histamine, sedating antihistamines at night are helpful to break the itch-scratch cycle. Chronic itch may also be treated with other systemic therapies, such as anticonvulsants, antidepressants as well as mu-opioid antagonists, kappa-opioid agonists and phototherapy, depending on the cause of the itch. This article summarises the topical and systemic therapies available with our current understanding of the pathophysiology of itch.

New series of avenanthramides in oat seed

Avenanthramides are characteristic constituents of oat seeds. We analyzed the methanol extract of oat seeds by HPLC and detected three compounds 1, 2, and 3 eluted at retention times similar to avenanthramides. The three compounds were purified by column chromatography and HPLC. Spectroscopic analyses of 1, 2, and 3 suggested that they are amides of 4,5-dihydroxyanthranilic acid with caffeic, p-coumaric, and ferulic acids, respectively. Their identities were confirmed by comparing spectra and chromatographic behavior with compounds synthesized from 4,5-dihydroxyanthranilic acid and N-hyrdroxysuccinimide esters of hydroxycinnamic acids. LC-MS/MS analysis with multiple reaction monitoring showed that the amounts of 1, 2, and 3 were 16.5–26.9% of corresponding avenanthamides with 5-hydroxyanthranilic acid. Compounds 1, 2, and 3 showed stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity than the corresponding avenanthramides with 5-hydroxyanthranilic acid, indicating the involvement of 4,5-dihydroxyanthranilic acid moiety in the scavenging of DPPH radicals.

Dihydroavenanthramide D prevents UV-irradiated generation of reactive oxygen species and expression of matrix metalloproteinase-1 and -3 in human dermal fibroblasts

Ultraviolet B (UVB) radiation induces photoageing by upregulating the expression of matrix metalloproteinases (MMPs) in human skin cells. Dihydroavenanthramide D (DHAvD) is a synthetic analog to naturally occurring avenanthramide, which is the active component in oats. Although anti-inflammatory, anti-atherosclerotic and antioxidant effects have been reported, the antiphotoageing effects of DHAvD are yet to be understood. In this study, we investigated the inhibitory effects of DHAvD on UVB-induced production of reactive oxygen species (ROS) and expression of MMPs, and its molecular mechanism in UVB-irradiated human dermal fibroblasts. Western blot and real-time PCR analyses revealed that DHAvD inhibited UVB-induced MMP-1 and MMP-3 expression. It also significantly blocked UVB-induced ROS generation in fibroblasts. Additionally, DHAvD attenuated UVB-induced phosphorylation of MAPKs, activation of NF-κB and AP-1. DHAvD regulates UVB-irradiated MMP expression by inhibiting ROS-mediated MAPK/NF-κB and AP-1 activation. DHAvD may be a useful candidate for preventing UV light-induced skin photoageing.

An emulsion restores the skin barrier by decreasing the skin pH and inflammation in a canine experimental model

The aim of this study was to investigate the effect of Douxo(®) Calm Mousse (Sogeval, Laval, France) on restoration of the skin barrier in a canine model of barrier disruption. Tape strips were performed, daily for 6 days, on the lateral thorax of five healthy beagle dogs. Douxo(®) Calm Mousse was applied daily for 5 days to one side of the thorax and the opposite side was left untreated. The effects of treatment were evaluated by measurement of transepidermal water loss (TEWL) and pH and by histological assessment of disrupted skin at various times during barrier repair. Although no effect on TEWL was observed, Douxo(®) Calm Mousse maintained an acidic pH after three applications and reduced skin inflammation, which was most pronounced after five applications. The results of the study suggest that Douxo(®) Calm Mousse exerts a beneficial effect on barrier restoration and on markers of inflammation.

Avenanthramide supplementation attenuates exercise-induced inflammation in postmenopausal women

During aging, chronic systemic inflammation increases in prevalence and antioxidant balance shifts in favor of oxidant generation. Avenanthramide (AVA) is a group of oat phenolics that have shown anti-inflammatory and antioxidant capability. The present study investigated whether dietary supplementation of avenanthramides (AVA) in oats would increase antioxidant protection and reduce inflammation after a bout of downhill walking (DW) in postmenopausal women. Women at age of 50–80 years (N = 16) were randomly divided into two groups in a double-blinded fashion, receiving two cookies made of oat flour providing 9.2 mg AVA or 0.4 mg AVA (control, C) each day for 8 weeks. Before and after the dietary regimen, each group of subjects walked downhill on a treadmill (−9% grade) for 4 bouts of 15 minutes at a speed of 4.0 km/h with 5 minutes rest between sessions. Blood samples were collected at rest, 24 h post-DW, and 48 h post-DW pre- and post-supplementation. Both DW sessions increased plasma creatine kinase activity (P < 0.05). Before supplementation, in vitro neutrophil respiratory burst (NRB) activity was increased at 24 h post-DW (P < 0.05) and C-reactive protein (CRP) was increased 48 h post-DW (P < 0.05). AVA supplementation decreased DW-induced NRB at 24 h (P < 0.05) and CRP level 48 h (P < 0.05). Plasma interleukin (IL)-1β concentration and mononuclear cell nuclear factor (NF) κB binding were suppressed at rest and during post-DW period in AVA but not C group (P < 0.05). Plasma total antioxidant capacity (P < 0.05) and erythrocyte superoxide dismutase activity were increased in AVA vs. C (P < 0.05), whereas glutathione redox status was elevated 48 h post-DW but not affected by AVA. Thus, chronic AVA supplementation decreased systemic and DW-induced inflammation and increased blood-borne antioxidant defense in postmenopausal women.

Picea mariana polyphenolic extract inhibits phlogogenic mediators produced by TNF-α-activated psoriatic keratinocytes: Impact on NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Picea mariana ((Miller) Britton, Sterns, and Poggenburg; Pinaceae) bark has been traditionally used by North American natives for treating topical inflammations. It has been also suggested to improve various inflammatory skin disorders like Psoriasis vulgaris. Extracts from this bark storage protein contain polyphenolic compounds which have well-known antiinflammatory activities. Based on the capacity of polyphenolic compounds to modulate functions of normal human keratinocytes, this study was set up to decipher the mechanisms of action of a chemically characterized polyphenolic extract from Picea mariana bark (BS-EAcf) on lesional keratinocytes of skin with psoriasis vulgaris, a disease driven by the immune system in which TNF-α plays a significant role.

MATERIALS AND METHODS

BS-EAcf corresponds to the ethyl acetate soluble fraction from the hot water extract of Picea mariana bark. BS-EAcf effects were evaluated in normal human (NHK) and psoriatic (PK) keratinocytes stimulated by TNF-α. Cell viability was assessed by lactate deshydrogenase release and propidium iodide (PI) staining. The mechanisms of action of BS-EAcf in keratinocytes were investigated by flow cytometry, ELISAs, RT-PCR and western blot analyses.

RESULTS

PK exhibited a higher response to TNF-α than NHK regarding the ICAM-1 expression and the production of NO, IL-6, IL-8, fractalkine and PGE2, whereas BS-EAcf significantly inhibited this TNF-α-induced increase at concentrations without causing keratinocyte toxicity. Additionally, this extract significantly inhibited the TNF-α-induced release of elafin and VEGF by PK and NHK. Since TNF-α activation of most of these factors is dependent on the NF-κB pathway, this latter was studied in TNF-α-activated PK. BS-EAcf inhibited the TNF-α-induced phosphorylation and degradation of total IκBα as well as phosphorylation of NF-κB p65.

CONCLUSIONS

The ethyl acetate fraction from Picea mariana bark extract showed inhibitory effects of cytokines, chemokines, adhesion molecules, nitric oxide and prostaglandins produced by keratinocytes under TNF-α activation through down-regulating the NF-κB pathway. This study demontrated that this extract could be a potential antiinflammatory agent capable of improving psoriatic skin.

Chronic consumption of a wild green oat extract (Neuravena) improves brachial flow-mediated dilatation and cerebrovascular responsiveness in older adults

BACKGROUND

Heart health benefits have been attributed to regular consumption of oats. Preclinical evidence suggests that a wild green oat extract (WGOE) may improve vasodilator function, but this is yet to be evaluated in humans.

OBJECTIVE

To determine whether regular daily consumption of WGOE can influence vasodilator function in systemic and cerebral arteries.

METHODS

Thirty-seven healthy older adults (>60 years) completed a 24-week randomized, double-blind, placebo-controlled two-way crossover dietary intervention with 1500 mg/day of encapsulated WGOE or placebo. All assessments were conducted at the end of each 12-week intervention arm, after participants had fasted for at least 4 h and at least 18 h after they had taken their last dose of supplement. Flow-mediated dilatation (FMD) of the brachial artery and hypercapnia-induced increases of blood flow in the middle cerebral artery were used to measure systemic and cerebral vasodilator responsiveness (CVR), respectively.

RESULTS

Compared with placebo, WGOE supplementation increased CVR and FMD to a similar extent (42 and 41%, respectively, P < 0.01 for both). The improvements in CVR and FMD were not correlated. Resting blood pressure did not alter with supplementation. Dose and treatment duration were well tolerated by participants.

CONCLUSION

WGOE supplementation can improve vasodilator function in systemic and cerebral arteries, suggesting a potential role in the maintenance of cardiovascular health.

Production of hydroxycinnamoyl anthranilates from glucose in Escherichia coli

BACKGROUND

Oats contain hydroxycinnamoyl anthranilates, also named avenanthramides (Avn), which have beneficial health properties because of their antioxidant, anti-inflammatory, and antiproliferative effects. The microbial production of hydroxycinnamoyl anthranilates is an eco-friendly alternative to chemical synthesis or purification from plant sources. We recently demonstrated in yeast (Saccharomyces cerevisiae) that coexpression of 4-coumarate: CoA ligase (4CL) from Arabidopsis thaliana and hydroxycinnamoyl/benzoyl-CoA/anthranilate N-hydroxycinnamoyl/benzoyltransferase (HCBT) from Dianthus caryophyllusenabled the biological production of several cinnamoyl anthranilates upon feeding with anthranilate and various cinnamates. Using engineering strategies to overproduce anthranilate and hydroxycinnamates, we describe here an entire pathway for the microbial synthesis of two Avns from glucose in Escherichia coli.

RESULTS

We first showed that coexpression of HCBT and Nt4CL1 from tobacco in the E. coli anthranilate-accumulating strain W3110 trpD9923 allowed the production of Avn D [N-(4'-hydroxycinnamoyl)-anthranilic acid] and Avn F [N-(3',4'-dihydroxycinnamoyl)-anthranilic acid] upon feeding with p-coumarate and caffeate, respectively. Moreover, additional expression in this strain of a tyrosine ammonia-lyase from Rhodotorula glutinis (RgTAL) led to the conversion of endogenous tyrosine into p-coumarate and resulted in the production of Avn D from glucose. Second, a 135-fold improvement in Avn D titer was achieved by boosting tyrosine production using two plasmids that express the eleven genes necessary for tyrosine synthesis from erythrose 4-phosphate and phosphoenolpyruvate. Finally, expression of either the p-coumarate 3-hydroxylase Sam5 from Saccharothrix espanensis or the hydroxylase complex HpaBC from E. coli resulted in the endogenous production of caffeate and biosynthesis of Avn F.

CONCLUSION

We established a biosynthetic pathway for the microbial production of valuable hydroxycinnamoyl anthranilates from an inexpensive carbon source. The proposed pathway will serve as a platform for further engineering toward economical and sustainable bioproduction of these pharmaceuticals and other related aromatic compounds.

Agriculture and bioactives: achieving both crop yield and phytochemicals

Plants are fundamental elements of the human diet, either as direct sources of nutrients or indirectly as feed for animals. During the past few years, the main goal of agriculture has been to increase yield in order to provide the food that is needed by a growing world population. As important as yield, but commonly forgotten in conventional agriculture, is to keep and, if it is possible, to increase the phytochemical content due to their health implications. Nowadays, it is necessary to go beyond this, reconciling yield and phytochemicals that, at first glance, might seem in conflict. This can be accomplished through reviewing food requirements, plant consumption with health implications, and farming methods. The aim of this work is to show how both yield and phytochemicals converge into a new vision of agricultural management in a framework of integrated agricultural practices.

Phytochemicals attenuating aberrant activation of β-catenin in cancer cells

Phytochemicals are a rich source of chemoprevention agents but their effects on modulating the Wnt/β-catenin signaling pathway have remained largely uninvestigated. Aberrantly activated Wnt signaling can result in the abnormal stabilization of β-catenin, a key causative step in a broad spectrum of cancers. Here we report the modulation of lithium chloride-activated canonical Wnt/β-catenin signaling by phytochemicals that have antioxidant, anti-inflammatory or chemopreventive properties. The compounds were first screened with a cervical cancer-derived stable Wnt signaling reporter HeLa cell line. Positive hits were subsequently evaluated for β-catenin degradation, suppression of β-catenin nuclear localization and down-regulation of downstream oncogenic targets of Wnt/β-catenin pathway. Our study shows a novel degradation path of β-catenin protein in HeLa cells by Avenanthramide 2p (a polyphenol) and Triptolide (a diterpene triepoxide), respectively from oats and a Chinese medicinal plant. The findings present Avenanthramide 2p as a potential chemopreventive dietary compound that merits further study using in vivo models of cancers; they also provide a new perspective on the mechanism of action of Triptolide.

Safety and efficacy of personal care products containing colloidal oatmeal

BACKGROUND

Colloidal oatmeal is a natural ingredient used in the formulation of a range of personal care products for relief of skin dryness and itchiness. It is also used as an adjunctive product in atopic dermatitis. The safety of personal care products used on vulnerable skin is of particular importance and the risk of developing further skin irritations and/or allergies should be minimized.

METHODS

In a series of studies, we tested the safety of personal care products containing oatmeal (creams, cleansers, lotions) by assessing their irritant/allergenic potential on repeat insult patch testing, in safety-in-use and ocular studies using subjects with nonsensitive and sensitive skin. We also tested the skin moisturizing and repair properties of an oatmeal-containing skin care product for dry skin.

RESULTS

We found that oatmeal-containing personal care products had very low irritant potential as well as a very low allergenic sensitization potential. Low-level reactions were documented in 1.0% of subjects during the induction phase of repeat insult patch testing; one of 2291 subjects developed a persistent but doubtful low-level reaction involving edema during the challenge phase in repeat insult patch testing. No allergies were reported by 80 subjects after patch testing after in-use application. Sustained skin moisturizing was documented in subjects with dry skin that lasted up to 2 weeks after product discontinuation.

CONCLUSION

Our results demonstrate that colloidal oatmeal is a safe and effective ingredient in personal care products. No allergies were reported by consumers of 445,820 products sold during a 3-year period.

Chronic effects of a wild green oat extract supplementation on cognitive performance in older adults: a randomised, double-blind, placebo-controlled, crossover trial

Background and aim: Preliminary evaluation of a wild green oat extract (WGOE) (Neuravena^® ELFA^®955, Frutarom, Switzerland) revealed an acute cognitive benefit of supplementation. This study investigated whether regular daily WGOE supplementation would result in sustained cognitive improvements. Method: A 12-week randomised, double-blind, placebo-controlled cross-over trial of WGOE supplementation (1500 mg/day) versus placebo was undertaken in 37 healthy adults aged 67 ± 0.8 years (mean ± SEM). Cognitive assessments included the Stroop colour-word test, letter cancellation, the rule-shift task, a computerised multi-tasking test battery and the trail-making task. All assessments were conducted in Week 12 and repeated in Week 24 whilst subjects were fasted and at least 18 h after taking the last dose of supplement. Result: Chronic WGOE supplementation did not affect any measures of cognition. Conclusion: It appears that the cognitive benefit of acute WGOE supplementation does not persist with chronic treatment in older adults with normal cognition. It remains to be seen whether sustained effects of WGOE supplementation may be more evident in those with mild cognitive impairment.

Influence of polyphenols on allergic immune reactions: mechanisms of action

The increased incidence of allergic disease seems to rely on many factors. Among them, the association between genetic variations of the immune response and environmental pressure by allergens, infectious agents and pollutants should be taken into consideration. In alternative to conventional treatments with corticosteroids and antihistaminics, nutraceuticals have been shown to act on allergic disease either during allergic sensitisation or on consolidated disease. In this review, special emphasis is placed on the effects of dietary polyphenols on three major allergic diseases, namely atopic eczema, food allergy and asthma. Interference of polyphenols with T-helper 2 activation seems to be the main mechanism of their inhibitory effects on allergy development. Moreover, deficits of T-regulatory cells seem to play a pathogenic role in allergic disease and, therefore, these cells may represent a major target of polyphenol activity.

Effect of chemical systemic acquired resistance elicitors on avenanthramide biosynthesis in oat (Avena sativa)

Oats produce a group of phenolic antioxidants termed avenanthramides. These metabolites are, among food crops, unique to oats and have shown, in experimental systems, certain desirable nutritional characteristics such as inhibiting atherosclerotic plaque formation and reducing inflammation. Avenanthramides occur in both the leaves and grain of oat. In the leaves they are expressed as phytoalexins in response to crown rust (Puccina coronata) infection. The experiments reported here demonstrate that avenanthramide levels in vegetative tissue can be enhanced by treatment with benzothiadiazole (BTH), an agrochemical formulated to elicit systemic acquired resistance (SAR). The response to BTH was dramatically stronger than those produced with salicylic acid treatment. The roots of BTH treated plants also showed a smaller but distinct increase in avenanthramides. The dynamics of the root avenanthramide increase was substantially slower than that observed in the leaves, suggesting that avenanthramides might be transported from the leaves.

Avenanthramides are bioavailable and accumulate in hepatic, cardiac, and skeletal muscle tissue following oral gavage in rats

Avenanthramides (AVA), polyphenols found exclusively in oats ( Avena sativa L.), may play a role in the anti-inflammatory and antiatherogenic activity of oats. The bioavailability of AVA has been demonstrated previously, but its distribution at the organ and tissue level and the extent of conjugation following ingestion have been unexplored. Synthetic AVA was administered to 24 rats by oral gavage, whereas 6 control rats received saline. AVA concentrations were measured via HPLC in plasma, liver, heart, and gastrocnemius (GAS) obtained over a 12 h period (0, 2, 4, 12 h; n = 6 at each time point). Samples were extracted with and without glucuronidase-sulfatase to assess the level of conjugation. We conclude that AVA are bioavailable to the blood circulation following oral ingestion in the rat and reach peripheral tissues where they can be taken up by various organs differentially. With AVA remaining in the organs for up to 12 h, it seems possible to maintain an increased level of AVA in the rat via repeated feedings.

Dihydroavenanthramide D inhibits human breast cancer cell invasion through suppression of MMP-9 expression

Dihydroavenanthramide D (DHAvD) is a synthetic analog to naturally occurring avenanthramide, which is the active component of oat. Previous study demonstrates that DHAvD strongly inhibits activation of nuclear factor-kappa B (NF-κB), which is a major component in cancer cell invasion. The present study investigated whether DHAvD can modulate MMP-9 expression and cell invasion in MCF-7 human breast cancer cells. MMP-9 expression and cell invasion in response to 12-O-tetradecanoylphorbol-13-acetate (TPA) was increased, whereas these inductions were muted by DHAvD. DHAvD also suppressed activation of mitogen-activated protein kinase (MAPK), and MAPK-mediated nuclear factor-kappa B (NF-κB) and activator protein-1 (AP-1) activations in TPA-treated MCF-7 cells. The results indicate that DHAvD-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of the MAPK/NF-κB and MAPK/AP-1 pathways in MCF-7 cells. DHAvD may have potential value in breast cancer metastasis.

Naringenin chalcone suppresses allergic asthma by inhibiting the type-2 function of CD4 T cells

BACKGROUND

Some polyphenols possess anti-allergic activities. Naringenin chalcone is one of the polyphenols that is present in the skin of red tomatoes. In this study, we investigated the effect of naringenin chalcone in allergic responses in vivo using an experimental mouse model system of allergic asthma.

METHODS

Allergic airway inflammation was induced in mice by sensitization and challenge with ovalbumin. Naringenin chalcone was orally administrated every day during the course of the experiment. Airway hyperreactivity, the eosinophilic infiltration in the bronchioalveolar lavage fluid and Th2 cytokine production from splenic CD4 T cells were assessed.

RESULTS

Eosinophilic airway inflammation, airway hyperreactivity and Th2 cytokine production from CD4 T cells were significantly suppressed in mice that were treated with naringenin chalcone. Hyperproduction of mucus was slightly reduced.

CONCLUSIONS

The results of this study suggest that naringenin chalcone suppresses asthmatic symptoms by inhibiting Th2 cytokine production from CD4 T cells. Thus, naringenin chalcone may be a useful supplement for the suppression of allergic symptoms in humans.

Potential health benefits of avenanthramides of oats

Oats are known to be a healthy food for the heart due mainly to their high beta-glucan content. In addition, they contain more than 20 unique polyphenols, avenanthramides, which have shown strong antioxidant activity in vitro and in vivo. The polyphenols of oats have also recently been shown to exhibit anti-inflammatory, antiproliferative, and anti-itching activity, which may provide additional protection against coronary heart disease, colon cancer, and skin irritation.

Regulatory effects of a fermented food concentrate on immune function parameters in healthy volunteers

OBJECTIVE

Nutrition is known to influence the immune system and can thereby modulate resistance to infection. The objective of this clinical trial was to assess the influence of a cascade-fermented food consisting of fruits, nuts, and vegetables rich in polyphenols (Regulat) on the immune system in healthy volunteers.

METHODS

The clinical trial was double-blinded and placebo-controlled. In total, 48 healthy men 20-48 y of age with a body mass index of 20-28 kg/m(2) were enrolled in the clinical trial. The group was characterized according to lifestyle parameters and only men with regular low to moderate intake of fruit and vegetables were enrolled. The intervention lasted for a period of 4 wk. Volunteers received Regulat twice daily or a placebo product (essence of vinegar).

RESULTS

The intake of Regulat significantly enhanced intracellular glutathione content in lymphocytes (P < 0.05), monocytes (P < 0.05), and natural killer cells (P < 0.01). Furthermore, activation of natural killer cell cytotoxicity in response to interleukin-2 stimulation (P < 0.05), a reduction of total lipid peroxidation, and a reduction of soluble vascular cell adhesion molecule-1 (P < 0.01) and soluble intercellular adhesion molecule-1 (P < 0.05) as inflammatory blood markers were found in the Regulat but not in the placebo group.

CONCLUSION

In summary, the results from this intervention study demonstrate promising physiologic effects of immune regulation on the innate immune system and antioxidative and anti-inflammatory parameters after Regulat supplementation. However, these promising results need to be confirmed in more volunteers with a more prolonged application to ensure significant beneficial effects of Regulat in the general population.