ORCID Profile
0000-0002-5186-5579
Current Organisations
AgResearch Ltd
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Agresearch Grasslands Research Centre
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Publisher: MDPI AG
Date: 15-10-2018
DOI: 10.3390/NU10101510
Abstract: Dairy, as a major component of a high protein diet, is a critical dietary source of branched chain amino acids (BCAA), which are biomarkers of health and diseases. While BCAA are known to be key stimulators of protein synthesis, elevated circulatory BCAA is an independent risk factor for type 2 diabetes mellitus. This study examined the impact of altered dairy intake on plasma BCAA and their potential relationship to insulin sensitivity. Healthy adults (n = 102) were randomized to receive dietary advice to reduce, maintain, or increase habitual dairy intake for 1 month. Food intake was recorded with food frequency questionnaires. Self-reported protein intake from dairy was reported to be reduced (−14.6 ± 3.0 g/day), maintained (−4.0 ± 2.0 g/day) or increased (+13.8 ± 4.1 g/day) according to group allocation. No significant alterations in circulating free amino acids (AA), including BCAA, were measured. Insulin sensitivity, as assessed by homeostatic model assessment-insulin resistance (HOMA-IR), was also unaltered. A significant change in dairy protein intake showed no significant effect on fasting circulatory BCAA and insulin sensitivity in healthy populations.
Publisher: Elsevier BV
Date: 06-2018
Publisher: Springer Science and Business Media LLC
Date: 27-09-2007
Publisher: Elsevier BV
Date: 2020
DOI: 10.1093/AJCN/NQZ279
Abstract: Lactose malabsorption (LM) is a major cause of digestive discomfort from dairy products. Recently, a role for bovine β-casein A1 has been proposed. We examined whether there are distinct symptoms of digestive discomfort due to either lactose or differing bovine β-casein types. Women (n = 40 age: 25.2 ± 0.5 y) with self-reported varying dairy tolerance underwent a 50-g lactose challenge. Based on postchallenge LM and digestive discomfort, participants were classified as either lactose intolerant (LI n = 10, self-reported intolerant, diagnosed lactose intolerant), nonlactose dairy intolerant (NLDI n = 20, self-reported intolerant, diagnosed lactose tolerant), or dairy tolerant (DT n = 10, self-reported tolerant, diagnosed lactose tolerant). In a double-blinded randomized sequence, participants consumed 750 mL conventional milk (CON containing A1 and A2 β-casein and lactose), a2 Milk (A2M exclusively containing A2 β-casein with lactose), or lactose-free conventional milk (LF-CON containing A1 and A2 β-casein without lactose). Subjective digestive symptoms and breath hydrogen (measuring LM) were recorded regularly over 3 h, and further ad hoc digestive symptoms over 12 h. LI subjects experienced prolonged digestive discomfort with CON milk. A2M reduced (P < 0.05) some symptoms (nausea: A2M 8 ± 3 mm compared with CON 15 ± 3mm fecal urgency: A2M 4 ± 1 compared with CON 10 ± 3 mm), and attenuated the rise in breath hydrogen over 3 h, relative to CON milk (A2M 59 ± 23 compared with CON 98 ± 25 ppm at 150 min P < 0.01). In contrast, NLDI subjects experienced rapid-onset, transient symptoms (abdominal distension, bloating, and flatulence) without increased breath hydrogen, irrespective of milk type. In LI in iduals, LM and digestive comfort with lactose-containing milks was improved with milk containing exclusively A2 β-casein. Furthermore, self-reported dairy intolerance without LM (NLDI) is characterized by early-onset digestive discomfort following milk ingestion, irrespective of lactose content or β-casein type. This trial was registered at www.anzctr.org.au as ACTRN12616001694404.
Publisher: Informa UK Limited
Date: 20-03-2014
DOI: 10.3109/09637486.2014.898260
Abstract: We compared the gastrointestinal effects of milk-based diets in which the β-casein component was either the A1 or A2 type in male Wistar rats fed the experimental diets for 36 or 84 h. Gastrointestinal transit time was significantly greater in the A1 group, as measured by titanium dioxide recovery in the last 24 h of feeding. Co-administration of naloxone decreased gastrointestinal transit time in the A1 diet group but not in the A2 diet group. Colonic myeloperoxidase and jejunal dipeptidyl peptidase (DPP)-4 activities were greater in the A1 group than in the A2 group. Naloxone attenuated the increase in myeloperoxidase activity but not that in DPP-4 activity in the A1 group. Naloxone did not affect myeloperoxidase activity or DPP-4 activity in the A2 group. These results confirm that A1 β-casein consumption has direct effects on gastrointestinal function via opioid-dependent (gastrointestinal transit and myeloperoxidase activity) and opioid-independent (DPP-4 activity) pathways.
Publisher: Wiley
Date: 24-09-2010
Abstract: Oleic acid (OA) has been used as a control fatty acid in dietary polyunsaturated fatty acid (PUFA) intervention studies due to its lack of effect on eiconasoid biosynthesis. Since the effect of OA as a control fatty acid has not yet been investigated for transcriptomics and proteomics studies, this study aimed to test whether colonic transcriptome and proteome profiles associated with colitis development in mice fed a linoleic acid-rich corn oil-AIN-76A diet (Il10(-/-) compared to C57 mice) where similar to those of OA-fed Il10(-/-) compared to C57 mice (genotype comparison). A close clustering of colonic gene and protein expression profiles between the mice fed the AIN-76A or OA diet was observed. Inflammation-induced regulatory processes associated with cellular and humoral immune responses, cellular stress response and metabolic processes related to energy utilization were identified in Il10(-/-) compared to C57 mice fed either diet. Thus OA was considered as a suitable control unsaturated fatty acid for use in multi-omics PUFA studies. The second aim of this study was to test the effect of an OA-enriched AIN-76A diet compared to a linoleic acid-rich corn oil-AIN-76A diet on colonic transcriptome and proteome changes within Il10(-/-) or C57 mice (diet comparison). Overall, there was a limited concordance observed between measureable transcriptomics and proteomics profiles for genotype and diet comparisons. This underlines the importance and validity of a systems biology approach to understand the effects of diet on gene expression as a function of the genotype.
Publisher: MDPI
Date: 08-03-2023
Publisher: Cambridge University Press (CUP)
Date: 09-12-2011
DOI: 10.1017/S0007114511005241
Abstract: Inflammatory bowel disease (IBD) is a collective term for conditions characterised by chronic inflammation of the gastrointestinal tract involving an inappropriate immune response to commensal micro-organisms in a genetically susceptible host. Previously, aqueous and ethyl acetate extracts of gold kiwifruit ( Actinidia chinensis ) or green kiwifruit ( A. deliciosa ) have demonstrated anti-inflammatory activity using in vitro models of IBD. The present study examined whether these kiwifruit extracts (KFE) had immune-modulating effects in vivo against inflammatory processes that are known to be increased in patients with IBD. KFE were used as a dietary intervention in IL-10-gene-deficient ( Il10 − / − ) mice (an in vivo model of IBD) and the C57BL/6J background strain in a 3 × 2 factorial design. While all Il10 − / − mice developed significant colonic inflammation compared with C57BL/6J mice, this was not affected by the inclusion of KFE in the diet. These findings are in direct contrast to our previous study where KFE reduced inflammatory signalling in primary cells isolated from Il10 − / − and C57BL/6J mice. Whole-genome gene and protein expression level profiling indicated that KFE influenced immune signalling pathways and metabolic processes within the colonic tissue however, the effects were subtle. In particular, expression levels across gene sets related to adaptive immune pathways were significantly reduced using three of the four KFE in C57BL/6J mice. The present study highlights the importance of investigating food components identified by cell-based assays with appropriate in vivo models before making dietary recommendations, as a food that looks promising in vitro may not be effective in vivo.
Publisher: Open Access Text Pvt, Ltd.
Date: 2015
Publisher: Springer Science and Business Media LLC
Date: 14-02-2018
DOI: 10.1007/S00394-018-1620-6
Abstract: Elemental deficiencies are highly prevalent and have a significant impact on health. However, clinical monitoring of plasma elemental responses to foods remains largely unexplored. Data from in vitro studies show that red meat (beef) is a highly bioavailable source of several key elements, but cooking method may influence this bioavailability. We therefore studied the postprandial responses to beef steak, and the effects of two different cooking methods, in healthy young males. In a randomized cross-over controlled trial, healthy males (n = 12, 18-25 years) were fed a breakfast of beef steak (270 ± 20 g) in which the meat was either pan-fried (PF) or sous-vide (SV) cooked. Baseline and postprandial blood s les were collected and the plasma concentrations of 15 elements measured by inductively coupled plasma-mass spectrometry (ICP-MS). Concentrations of Fe and Zn changed after meal ingestion, with plasma Fe increasing (p < 0.001) and plasma Zn decreasing (p < 0.05) in response to both cooking methods. The only potential treatment effect was seen for Zn, where the postprandial area under the curve was lower in response to the SV meal (2965 ± 357) compared to the PF meal (3190 ± 310 p < 0.05). This multi-element approach demonstrated postprandial responsiveness to a steak meal, and an effect of the cooking method used. This suggests the method would provide insight in future elemental metabolic studies to evaluate responses to meat-based meals, including longer-term interventions in more specifically defined cohorts to clearly establish the role of red meat as an important source of elements.
Publisher: Springer Science and Business Media LLC
Date: 09-03-2015
DOI: 10.1007/S12603-015-0500-5
Abstract: To measure the postprandial plasma amino acid appearance in younger and older adults following a high protein mixed meal. Cross-sectional study. Clinical research setting. Healthy men and women aged 60-75 (n=15) years, and young controls aged 20-25 years (n=15) matched for body mass index and insulin sensitivity based on the homeostatic model assessment of insulin resistance. High protein mixed meal of complete food products. Circulating amino acid concentrations were determined hourly before and for 5 hours after meal ingestion. There was no difference between cohorts in postprandial appearance of non-essential amino acids, or area under the curve of any in idual amino acid or amino acid class. However, older adults had higher baseline concentrations of aspartic acid, glutamic acid, glycine, ornithine, threonine and tyrosine and lower baseline concentrations of hydroxyproline, isoleucine, leucine, methionine and valine compared to younger adults. Younger adults showed peak essential (EAA) and branched-chain amino acid (BCAA) concentrations at 1 hour post meal while older adults' peak EAA and BCAA concentration was at 3 hours. Similarly, peak total amino acid concentrations were at 3 hours in older adults. Older adults digested and absorbed the protein within a mixed meal more slowly than younger adults. Delayed absorption of AA following a mixed meal of complete food products may suppress or delay protein synthesis in senescent muscle.
Publisher: American Physiological Society
Date: 03-2016
DOI: 10.1152/AJPREGU.00351.2015
Abstract: A high-saturated-fat diet (HFD) during pregnancy and lactation leads to metabolic disorders in offspring concomitant with increased adiposity and a proinflammatory phenotype in later life. During the fetal period, the impact of maternal diet on skeletal muscle development is poorly described, despite this tissue exerting a major influence on life-long metabolic health. This study investigated the effect of a maternal HFD on skeletal muscle anabolic, catabolic, and inflammatory signaling in adult rat offspring. Furthermore, the actions of maternal-supplemented conjugated linoleic acid (CLA) on these measures of muscle phenotype were investigated. A purified control diet (CD 10% kcal fat), a CD supplemented with CLA (CLA 10% kcal fat, 1% total fat as CLA), a high-fat (HFD 45% kcal fat from lard), or a HFD supplemented with CLA (HFCLA 45% kcal fat from lard, 1% total fat as CLA) was fed ad libitum to female Sprague-Dawley rats for 10 days before mating and throughout gestation and lactation. Male offspring received a standard chow diet from weaning, and the gastrocnemius was collected for analysis at day 150. Offspring from HF and HFCLA mothers displayed lower muscular protein content accompanied by elevated monocyte chemotactic protein-1, IL-6, and IL-1β concentrations. Phosphorylation of NF-κBp65 (Ser 536 ) and expression of the catabolic E3 ligase muscle ring finger 1 (MuRF1) were increased in HF offspring, an effect reversed by maternal CLA supplementation. The present study demonstrates the importance of early life interventions to ameliorate the negative effects of poor maternal diet on offspring skeletal muscle development.
Publisher: MDPI AG
Date: 11-03-2015
DOI: 10.3390/NU7031798
Publisher: MDPI AG
Date: 17-11-2020
DOI: 10.3390/NU12113529
Abstract: Multivitamin and mineral (MVM) supplements are frequently used amongst older populations to improve adequacy of micronutrients, including B-vitamins, but evidence for improved health outcomes are limited and deficiencies remain prevalent. Although this may indicate poor efficacy of supplements, this could also suggest the possibility for altered B-vitamin bioavailability and metabolism in older people. This open-label, single-arm acute parallel study, conducted at the Liggins Institute Clinical Research Unit in Auckland, compared circulatory and urinary B-vitamer responses to MVM supplementation in older (70.1 ± 2.7 y, n = 10 male, n = 10 female) compared to younger (24.2 ± 2.8 y, n = 10 male, n = 10 female) participants for 4 h after the ingestion of a single dose of a commercial MVM supplement and standardized breakfast. Older adults had a lower area under the curve (AUC) of postprandial plasma pyridoxine (p = 0.02) and pyridoxal-5′phosphate (p = 0.03) forms of vitamin B6 but greater 4-pyridoxic acid AUC (p = 0.009). Urinary pyridoxine and pyridoxal excretion were higher in younger females than in older females (time × age × sex interaction, p 0.05). Older adults had a greater AUC increase in plasma thiamine (p = 0.01), riboflavin (p = 0.009), and pantothenic acid (p = 0.027). In older adults, there was decreased plasma responsiveness of the ingested (pyridoxine) and active (pyridoxal-5′phosphate) forms of vitamin B6, which indicated a previously undescribed alteration in either absorption or subsequent metabolic interconversion. While these findings cannot determine whether acute B6 responsiveness is adequate, this difference may have potential implications for B6 function in older adults. Although this may imply higher B vitamin substrate requirements for older people, further work is required to understand the implications of postprandial differences in availability.
Publisher: Elsevier BV
Date: 08-2010
DOI: 10.1016/J.MRFMMM.2010.02.006
Abstract: Epigenomic regulation, via DNA methylation, histone modification and non-coding RNA, is increasingly recognised as having a key role in normal development and function of an organism, acting to control cellular and tissue growth and differentiation. It is also thought to be involved in many complex diseases now common in the Western world, including cardiovascular disease, type 2 diabetes, obesity and inflammatory bowel disease (IBD). There is a range of evidence to suggest that nutrition plays a vital role in the protection from such diseases. However, there is little information about the role of nutrition on the epigenetic regulation of IBD. This review aims to elucidate the interactions of nutrients and the epigenome in IBD. More specifically, the plasticity of epigenetic modifications that occur due to low selenium and folate levels in the diet during gestation and lactation will be discussed. A better understanding of this plasticity, and of nutrient-epigenome interactions, will have important implications for enhancing human health through foods.
Publisher: MDPI AG
Date: 08-05-2015
DOI: 10.3390/NU7053370
Publisher: MDPI AG
Date: 17-07-2019
DOI: 10.3390/NU11071636
Abstract: Hydrogen (H2) measurement in exhaled breath is a reliable and non-invasive method to diagnose carbohydrate malabsorption. Currently, breath H2 measurement is typically limited to clinic-based equipment. A portable breath analyser (AIRE, FoodMarble Digestive Health Limited, Dublin, Ireland) is a personalised device marketed for the detection and self-management of food intolerances, including lactose malabsorption (LM). Currently, the validity of this device for breath H2 analysis is unknown. In iduals self-reporting dairy intolerance (six males and six females) undertook a lactose challenge and a further seven in iduals (all females) underwent a milk challenge. Breath s les were collected prior to and at frequent intervals post-challenge for up to 5 h with analysis using both the AIRE and a calibrated breath hydrogen analyser (BreathTracker, QuinTron Instrument Company Inc., Milwaukee, WI, USA). A significant positive correlation (p 0.001, r 0.8) was demonstrated between AIRE and BreathTracker H2 values, after both lactose and milk challenges, although 26% of the AIRE readings demonstrated the maximum score of 10.0 AU. Based on our data, the cut-off value for LM diagnosis (25 ppm H2) using AIRE is 3.0 AU and it is effective for the identification of a response to lactose-containing foods in in iduals experiencing LM, although its upper limit is only 81 ppm.
Publisher: Springer Science and Business Media LLC
Date: 2010
Publisher: Elsevier BV
Date: 2016
DOI: 10.1016/J.JNUTBIO.2015.08.030
Abstract: The aim of this study was to provide insight into how curcumin reduces colon inflammation in the Mdr1a(-/-) mouse model of human inflammatory bowel disease using a combined transcriptomics and proteomics approach. Mdr1a(-/-) and FVB control mice were randomly assigned to an AIN-76A (control) diet or AIN-76A+0.2% curcumin. At 21 or 24weeks of age, colonic histological injury score (HIS) was determined, colon mRNA transcript levels were assessed using microarrays and colon protein expression was measured using 2D gel electrophoresis and LCMS protein identification. Colonic HIS of Mdr1a(-/-) mice fed the AIN-76A diet was higher (P<.001) than FVB mice fed the same diet the curcumin-supplemented diet reduced colonic HIS (P<.05) in Mdr1a(-/-) mice. Microarray and proteomics analyses combined with new data analysis tools, such as the Ingenuity Pathways Analysis regulator effects analysis, showed that curcumin's antiinflammatory activity in Mdr1a(-/-) mouse colon may be mediated by activation of α-catenin, which has not previously been reported. We also show evidence to support curcumin's action via multiple molecular pathways including reduced immune response, increased xenobiotic metabolism, resolution of inflammation through decreased neutrophil migration and increased barrier remodeling. Key transcription factors and other regulatory molecules (ERK, FN1, TNFSF12 and PI3K complex) activated in inflammation were down-regulated by dietary intervention with curcumin.
Publisher: Elsevier BV
Date: 10-2013
DOI: 10.1016/J.JNUTBIO.2013.02.007
Abstract: Animal models are an important tool to understand the complex pathogenesis of inflammatory bowel diseases (IBDs). This study tested the anti-inflammatory potential of a green tea extract rich in polyphenols (GrTP) in the colon of the multidrug resistance targeted mutation (Mdr1a(-/-)) mouse model of IBD. Insights into mechanisms responsible for this reduction in inflammation were gained using transcriptome and proteome analyses. Mice were randomly assigned to an AIN-76A (control) or GrTP-enriched diet. At 21 or 24 weeks of age, a colonic histological injury score was determined for each mouse, colon mRNA transcript levels were assessed using microarrays, and colon protein expression was measured using two-dimensional gel electrophoresis and liquid chromatography-mass spectrometry protein identification. Mean colonic histological injury score of GrTP-fed Mdr1a(-/-) mice was significantly lower compared to those fed the control diet. Microarray and proteomics analyses showed reduced abundance of transcripts and proteins associated with immune and inflammatory response and fibrinogenesis pathways, and increased abundance of those associated with xenobiotic metabolism pathways in response to GrTP, suggesting that its anti-inflammatory activity is mediated by multiple molecular pathways. Peroxisome proliferator-activated receptor-α and signal transducer and activator of transcription 1 appear to be two key molecules which regulate these effects. These results support the view that dietary intake of polyphenols derived from green tea can ameliorate intestinal inflammation in the colon of a mouse model of IBD, and are in agreement with studies suggesting that consumption of green tea may reduce IBD symptoms and therefore play a part in an overall IBD treatment regimen.
Publisher: Hindawi Limited
Date: 2010
DOI: 10.1155/2010/621069
Abstract: The interleukin-10 gene-deficient ( Il 10 - / - ) mouse is a model of human inflammatory bowel disease and Ppara has been identified as one of the key genes involved in regulation of colitis in the bacterially inoculated Il 10 - / - model. The aims were to (1) characterize colitis onset and progression using a histopathological, transcriptomic, and proteomic approach and (2) investigate links between PPAR α and IL10 using gene network analysis. Bacterial inoculation resulted in severe colitis in Il 10 - / - mice from 10 to 12 weeks of age. Innate and adaptive immune responses showed differences in gene expression relating to colitis severity. Actin cytoskeleton dynamics, innate immunity, and apoptosis-linked gene and protein expression data suggested a delayed remodeling process in 12-week-old Il 10 - / - mice. Gene expression changes in 12-week-old Il 10 - / - mice were related to PPAR α signaling likely to control colitis, but how PPAR α activation might regulate intestinal IL10 production remains to be determined.
Publisher: Springer Science and Business Media LLC
Date: 03-03-2016
Publisher: Elsevier BV
Date: 08-2010
DOI: 10.1016/J.MRFMMM.2009.12.006
Abstract: Many milk-derived components have immunomodulatory and anti-inflammatory properties, and some of these reduce intestinal inflammation when orally administered to animal models of colitis. However, the potential for ruminant milk or milk components to benefit people with intestinal inflammatory disorders (such as Inflammatory Bowel Disease) has not been well-researched. This review describes published research into mechanisms by which ruminant milk and its components may have beneficial effects when consumed by people who have intestinal inflammation.
Publisher: Springer Science and Business Media LLC
Date: 22-04-2022
DOI: 10.1038/S41430-022-01119-0
Abstract: Self-reported digestive intolerance to dairy foods is common. As dairy can be an important source of dietary protein, this study aimed to identify whether milk protein digestion is compromised in in iduals with digestive intolerance. Adult women ( n = 40) were enroled in this double-blinded, randomised cross-over trial, with digestive symptoms characterised using a lactose challenge and self-reported digestive symptom questionnaire. Participants were classified as either lactose intolerant (LI, n = 10), non-lactose dairy intolerant (NLDI, n = 20) or dairy tolerant (DT, n = 10). In a randomised sequence, participants consumed three different kinds of milk (750 ml) conventional milk (CON), a2 Milk™ (A2M), and lactose-free conventional milk (LF-CON). Circulatory plasma amino acid (AA) concentrations were measured at baseline and every 30 min until 3 h post-ingestion. In all participants across all milk types, plasma AA concentrations (AUC 0-180 ) increased after milk ingestion with no significant differences in responses observed between milk types or participants ( P 0.05), with the exception of the suppressed lysine response in the DT group following A2M ingestion, relative to the other two groups and milk types ( P 0.05). Milk protein digestion, as determined by circulatory AAs, is largely unaffected by dairy- and lactose- intolerances.
Publisher: MDPI AG
Date: 31-01-2020
DOI: 10.3390/NU12020380
Abstract: Cooking changes the texture and tenderness of red meat, which may influence its digestibility, circulatory amino acids (AA) and gastrointestinal (GI) hormonal responses in consumers. In a randomised crossover intervention, healthy males (n = 12) consumed a beef steak sandwich, in which the beef was cooked by either a pan-fried (PF) or sous-vide (SV) method. Plasma AA were measured by ultrahigh performance liquid chromatography (UPLC), while plasma GI hormones were measured using a flow cytometric multiplex array. Following meat ingestion, the circulatory concentrations of some of the essential AA (all the branched-chain AA: leucine, isoleucine and valine and threonine), some of the nonessential AA (glycine, alanine, tyrosine and proline) and some of the nonproteogenic AA (taurine, citrulline and ornithine) were increased from fasting levels by 120 or 180 min (p 0.05). There were no differences in circulating AA concentrations between cooking methods. Likewise, of the measured GI hormones, glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 (GLP-1) concentrations increased from fasting levels after consumption of the steak sandwich (p 0.05), with no differences between the cooking methods. In the healthy male adults, protein digestion and circulating GI hormone responses to a beef-steak breakfast were unaltered by the different cooking methods.
Publisher: Microbiology Society
Date: 11-2010
Abstract: Interleukin-10 gene-deficient ( Il10 –/– ) mice show a hyper-reaction to normal intestinal bacteria and develop spontaneous colitis similar to that of human Crohn's disease when raised under conventional (but not germ-free) conditions. The lack of IL10 protein in these mice leads to changes in intestinal metabolic and signalling processes. The first aim of this study was to identify changes in the bacterial community of the caeca at 7 weeks of age (preclinical colitis) and at 12 weeks of age (when clinical signs of colitis are present), and establish if there were any changes that could be associated with the mouse genotype. We have previously shown that dietary n-3 and n-6 polyunsaturated fatty acids (PUFA) have anti-inflammatory effects and affect colonic gene expression profiles in Il10 –/– mice therefore, we also aimed to test the effect of the n-3 PUFA eicosapentaenoic acid (EPA) and the n-6 PUFA arachidonic acid (AA) on the bacterial community of caeca in both Il10 –/– and C57 mice fed these diets. The lower number of caecal bacteria observed before colitis (7 weeks of age) in Il10 –/– compared to C57 mice suggests differences in the intestinal bacteria that might be associated with the genotype, and this could contribute to the development of colitis in this mouse model. The number and ersity of caecal bacteria increased after the onset of colitis (12 weeks of age). The increase in caecal Escherichia coli numbers in both inflamed Il10 –/– and healthy C57 mice might be attributed to the dietary PUFA (especially dietary AA), and thus not be a cause of colitis development. A possible protective effect of E. coli mediated by PUFA supplementation and associated changes in the bacterial environment could be a subject for further investigation to define the mode of action of PUFA in colitis.
Publisher: S. Karger AG
Date: 22-10-2008
DOI: 10.1159/000134292
Abstract: i Background/Aims: /i Dietary n–3 polyunsaturated fatty acids can reduce inflammation via a range of mechanisms. This study tested the effect of dietary eicosapentaenoic acid (EPA) on intestinal inflammation using interleukin-10 gene-deficient i (Il10 /i sup –/– /sup i ) /i mice. i Methods: /i At 35 days of age, 12 weaned i Il10 /i sup –/– /sup and 12 C57 mice were randomly assigned to one of two modified AIN-76A diets, supplemented with 3.7% purified ethyl esters of either EPA (n–3) or oleic acid (OA, control). To identify genes relevant to colon inflammation, transcription profiling (microarrays and qRT-PCR) and bioinformatic analyses were used. i Results: /i In this study, dietary EPA reversed the decrease in colon fatty acid β-oxidation gene expression observed in OA-fed i Il10 /i sup –/– /sup compared to C57 mice. i Il10 /i sup –/– /sup mice fed the OA diet showed decreased expression of antioxidant enzyme genes, as well as those involved in detoxification of xenobiotics, compared to C57 mice on the same diet. In contrast, dietary EPA increased the expression of these genes in i Il10 /i sup –/– /sup mice. i Conclusions: /i These data indicate that dietary EPA-induced endogenous lipid oxidation which might have a potential anti-inflammatory effect on colon tissue. This is supported by the activation of the i Ppara /i gene that regulates the expression of pro-inflammatory and immunomodulatory genes and proteins.
Publisher: Wiley
Date: 05-2010
Abstract: Increased levels of n-6 arachidonic acid (AA), a precursor of pro-inflammatory eicosanoids, have been found in the colon mucosa of inflammatory bowel disease patients when compared with healthy subjects. The hypothesis was that dietary AA would aggravate colon inflammation by changing expression of genes in inflammatory signaling pathways. AA-enriched diet was fed to IL10 gene-deficient (Il10-/-) mice, model of a inflammatory bowel disease, and compared with Il10-/- mice fed an oleic acid control diet. Effects of AA on gene expression profiles during colitis were examined using whole genome microarray analysis. Dietary AA decreased the expression levels of some colonic genes in ER stress, complement system, nuclear respiratory factor 2-mediated oxidative stress and positive acute phase response pathways compared with Il10-/- mice fed an oleic acid diet. AA increased the expression levels of fatty acid catabolism genes, but decreased that of lipid synthesis genes during colitis, likely by sterol regulatory element binding transcription factor 1 and target gene regulation. A link has been suggested between AA and reduction of intestinal fibrosis by down-regulating the expression levels of pro-inflammatory and fibrotic marker genes. Contrary to the hypothesis, these findings suggest that dietary AA, in the present experimental conditions, is not pro-inflammatory, reduces ER stress and protects colonocytes from oxidative stress in Il10-/- mice.
Publisher: Editorial CSIC
Date: 11-12-2008
DOI: 10.3989/GYA.086508
Publisher: Cambridge University Press (CUP)
Date: 02-09-2008
DOI: 10.1017/S0007114508009847
Abstract: Damage of the intestinal epithelial barrier by xenobiotics or reactive oxygen species and a dysregulated immune response are both factors involved in the pathogenesis of inflammatory bowel diseases (IBD). Curcumin and rutin are polyphenolic compounds known to have antioxidant and anti-inflammatory activities, but their mechanism(s) of action are yet to be fully elucidated. Multidrug resistance gene-deficient ( mdr1a − / − ) mice spontaneously develop intestinal inflammation, predominantly in the colon, with pathology similar to IBD, so this mouse model is relevant for studying diet–gene interactions and potential effects of foods on remission or development of IBD. The present study tested whether the addition of curcumin or rutin to the diet would alleviate colonic inflammation in mdr1a − / − mice. Using whole-genome microarrays, the effect of dietary curcumin on gene expression in colon tissue was also investigated. Twelve mice were randomly assigned to each of three diets (control (AIN-76A), control +0·2 % curcumin or control +0·1 % rutin) and monitored from the age of 7 to 24 weeks. Curcumin, but not rutin, significantly reduced histological signs of colonic inflammation in mdr1a − / − mice. Microarray and pathway analyses suggested that the effect of dietary curcumin on colon inflammation could be via an up-regulation of xenobiotic metabolism and a down-regulation of pro-inflammatory pathways, probably mediated by pregnane X receptor (Pxr) and peroxisome proliferator-activated receptor α (Ppara) activation of retinoid X receptor (Rxr). These results indicate the potential of global gene expression and pathway analyses to study and better understand the effect of foods in modulating colonic inflammation.
Publisher: Oxford University Press (OUP)
Date: 02-2016
Publisher: CSIRO Publishing
Date: 2008
DOI: 10.1071/EA08010
Abstract: Smart Foods, or foods with functions that confer health benefits, are the future of the food and nutrition sectors. Pastoral products such as milk and meat are easily manipulated to improve the health benefits of these products. Therefore, there is the potential for farmers to add value to their current products. Additionally, the identification of key nutrients for health and the prevention of disease using nutrigenomic and nutritional epigenetic approaches may identify new ways to manipulate milk and meat products. However, consumer perceptions of product efficacy and the marketing of foods with health claims will be drivers behind the uptake of Smart Foods in the future.
Publisher: Wiley
Date: 2016
DOI: 10.14814/PHY2.12670
Publisher: American Chemical Society (ACS)
Date: 13-12-2011
DOI: 10.1021/PR200807P
Abstract: Inflammatory bowel disease (IBD) is characterized by intestinal inflammation and is believed to involve complex interactions between genetic, immunological, and environmental factors. We measured changes in the proteome associated with bacterially induced intestinal inflammation in the interleukin 10 gene-deficient (Il10(-/-)) mouse model of IBD, established effects of the dietary polyunsaturated fatty acids (PUFAs) n-3 eicosapentaenoic acid (EPA) and n-6 arachidonic acid (AA) on protein expression (using oleic acid as a control fatty acid), and compared these changes with previously observed transcriptome changes in the same model. Ingenuity pathways analysis of proteomics data showed bacterially induced inflammation was associated with reduced expression of proteins from pathways of metabolism and digestion/absorption/excretion of nutrients/ions, and increased expression of cellular stress and immune response proteins. Both PUFA treatments showed anti-inflammatory activity EPA appeared to act via the PPARα pathway, whereas AA appeared to increase energy metabolism and cytoskeletal organization and reduce cellular stress responses, possibly enabling a more robust response to inflammation. While there was agreement between proteomic and transcriptomic data with respect to pathways, there was limited concordance between in idual gene and protein data, reflecting the importance of having both gene and protein data to better understand complex diseases such as IBD.
Publisher: Public Library of Science (PLoS)
Date: 20-05-2013
Publisher: Elsevier BV
Date: 09-2007
DOI: 10.1016/J.MRFMMM.2007.04.003
Abstract: In vivo models of Inflammatory Bowel Diseases (IBD) elucidate important mechanisms of chronic inflammation. Complex intestinal responses to food components create a unique "fingerprint" discriminating health from disease. Five-week-old IL10(-/-) and C57BL/6J (C57 control) mice were inoculated orally with complex intestinal microflora (CIF) and/or pure cultures of Enterococcus faecalis and E. faecalis (EF) aiming for more consistent inflammation of the intestinal mucosa. Inoculation treatments were compared to non-inoculated IL10(-/-) and C57 mice, either kept in specific pathogen free (SPF) or conventional conditions (2x5 factorial design). At 12 weeks of age, mice were sacrificed for intestinal histological (HIS) and transcriptomic analysis using limma and Ingenuity Pathway Analysis Software. Colonic HIS was significantly affected (P<0.05) in inoculated IL10(-/-) mice and accounted for approximately 60% of total intestinal HIS. Inoculation showed a strong effect on colonic gene expression, with more than 2000 genes differentially expressed in EF.CIF-inoculated IL10(-/-) mice. Immune response gene expression was altered (P<0.05) in these mice. The second study investigated the effect of arachidonic (AA) and eicosapentaenoic acid (EPA) on colonic HIS and gene expression to test whether EPA, contrary to AA, diminished intestinal inflammation in EF.CIF IL10(-/-) mice (2 x 4 factorial design). AIN-76A (5% corn oil) and AIN-76A (fat-free) +1% corn oil supplemented with either 3.7% oleic acid (OA), AA or EPA were used. IL10(-/-) mice fed EPA- and AA-enriched diets had at least 40% lower colonic HIS (P<0.05) than those fed control diets (AIN-76A and OA diets). The expression of immune response and 'inflammatory disease' genes (down-regulated: TNFalpha, IL6, S100A8, FGF7, PTGS2 up-regulated: PPARalpha, MGLL, MYLK, PPSS23, ABCB4 with EPA and/or AA) was affected in IL10(-/-) mice fed EPA- and AA-enriched diets, compared to those fed AIN-76A diet.
No related grants have been discovered for Matthew Barnett.