Regulation of adhesion molecule expression in human endothelial and smooth muscle cells by omega-3 fatty acids and conjugated linoleic acids: involvement of the transcription factor NF-kappaB?

We previously showed conjugated linoleic acids (CLA) inhibited TNF-alpha-induced monocyte (THP-1) adhesion to human umbilical vein endothelial cells (HUVEC) in vitro which involved an increase in platelet activating factor (PAF). Here we show adhesion molecule (ADM) regulation by fatty acids and the differing role of nuclear factor kappa B (NF-kappaB) activation in HUVEC and vascular smooth muscle cells (vSMC). CLA and omega-3 long-chain polyunsaturated fatty acids (PUFA) (FA) reduced TNF-alpha-induced expression of ADMs (intercellular adhesion molecule-1 (ICAM-1); vascular cell adhesion molecule-1 (VCAM-1) but not E-selectin) on HUVEC and vSMC to different extents depending on FA type and concentration, cell type and method of analysis. IkappaBalpha phosphorylation in HUVEC and vSMC and transient transfection with NF-kappaB-luciferase reporter plasmid (HUVEC only) indicated differential NF-kappaB involvement during FA modulation (cis-9, trans-11; trans-10, cis-12 and a 50:50 mix of both CLA isomers; eicosapentaenoic acid (EPA); docosahexaenoic acid (DHA)). TNF-alpha-induced ADM expression in both cell types by 2-10-fold. In HUVEC, CLA t10, c12 and CLA mix (50:50 mixture of CLA c9, t11 and t10, c12) and EPA and DHA reduced ICAM-1 expression (15-35%) at 12.5, 25 and/or 50 microM. VCAM-1 expression was reduced by 25 microM t10, c12 isomer and mix; omega-3 PUFA and other concentrations of CLA and TNF-alpha-induced E-selectin expression were unaffected. TNFalpha-induced inhibitor kappa B (IkappaB) phosphorylation was biphasic peaking at 5 min in both cell types and 60 and 120 min in HUVEC and SMC, respectively. IkappaBalpha phosphorylation and NF-kappaB activity was reduced (29% and 30%, respectively) by 25 microM CLA mix. n-3 PUFA did not reduce IkappaBalpha phosphorylation or NF-kappaB activity but reduced ADM expression. We show that n-3 PUFA and CLA reduce expression of ADM on HUVEC and vSMC. This reflected reduced adherence of monocytes to HUVEC previously reported by our group. Reduction of ICAM-1 and VCAM-1 protein expression by n-3 PUFA was less dependent on the NF-kappaB pathway than reduction by CLA which reflected the parallel attenuation of NF-kappaB activity. This indicated involvement of other transcription factors (i.e. AP-1) in the FA regulation of ADM expression and has, to our knowledge, not been previously reported.

Biomarkers of oxidative stress in schizophrenic and control subjects.

Increasing evidence indicates that oxidative injury exists in schizophrenia. Although it may not be the main cause, oxidative damage has been suggested to contribute to the pathophysiology and may account for deteriorating course and poor outcome in schizophrenia. A human study was undertaken, therefore, to investigate possible differences in biomarkers of DNA, lipid and protein oxidation in schizophrenic (n=16) and control subjects (n=17). Plasma vitamin C levels were also compared in both groups. Cellular DNA damage and plasma protein carbonyl levels were increased in the schizophrenic group compared to control subjects but not significantly. However, DNA damage in lymphocytes from the male schizophrenic group was significantly higher than the female group. Biomarkers of lipid peroxidation and plasma vitamin C levels also revealed no significant difference between the two groups under investigation, although a significant elevation in plasma vitamin C was observed in the female control group when compared to the male groups.

Effect of CLA supplementation on immune function in young healthy volunteers.

OBJECTIVES: This study investigated the effect of dietary CLA supplementation (3g/day; 50:50 mix of the two major isomers) on the immune system and plasma lipids and glucose of healthy human (male and female) volunteers. DESIGN: Double-blind, randomized, reference-controlled study. SUBJECT AND INTERVENTION: A total of 28 healthy male and female participants aged 25-50 y received either high oleic sunflower oil (reference) or 50% CLA 9-11 and 50% CLA 10-12 CLA isomers (50:50 CLA-triglyceride form). The treatments were given as supplements in soft-gel capsules providing a total 3 g (6 x 500 mg capsules) per day in treatment groups for 12 weeks. A 12-week washout period followed the intervention period. RESULTS: Levels of plasma IgA and IgM were increased (P < 0.05 and 0.01 respectively), while plasma IgE levels were decreased (P < 0.05). CLA supplementation also decreased the levels of the proinflammatory cytokines, TNF-alpha and IL-1beta (P < 0.05), but increased the levels of the anti-inflammatory cytokine, IL-10 (P < 0.05). Another aspect of immune function, delayed type hypersensitivity (DTH) response, was decreased during and after CLA supplementation (P < 0.05). However, plasma glucose, lipids, lymphocyte phenotypic results were not affected significantly by CLA. CONCLUSION: This is the first study to show that CLA, a fatty acid naturally found in dairy and meat products, can beneficially affect immune function in healthy human volunteers. SPONSORSHIP: This study was supported by Loders-Croklaan, The Netherlands and SEERAD (Scottish Executive Environmental Rural and Agriculture Department).

Nutrition and the surgical patient: triumphs and challenges.

The understanding of the role of nutrition in the surgical patient has lead to major developments in the nutritional support of patients undergoing surgery. Reductions in morbidity by ensuring that patients receive optimal nutritional support can be achieved. Furthermore, the use of nutrients to modify immune, inflammatory and metabolic processes also offers new possibilities for reducing morbidity following major surgery. However, we are only at an embryonic stage in our understanding of how nutrients and nutrition affect the genome and this knowledge offers exciting possibilities in the future for modulating many key intracellular processes, particularly in the patient with cancer.

Cell signal mechanisms, conjugated linoleic acids (CLAs) and anti-tumorigenesis.

Fats have been adversely implicated in the aetiology of many forms of cancer yet evidence is accumulating that certain types of fatty acids have anticancer properties. This is well documented for fish-oil fatty acids of the n-3 family. Recently, fatty acids found to occur naturally in ruminant-derived food products were found to have anticancer properties. These fatty acids were identified as conjugated linoleic acids (CLAs) derived from the parent linoleic acid by its partial hydrogenation by rumen bacteria. Studies with tumour-bearing animals have shown that consumption of CLAs particularly with regard to breast and prostate cancer is beneficial. Studies with cancer cells have also shown that these fatty acids can inhibit cell proliferation and induce cell death. However, little is known regarding the mechanisms of action of these CLAs. In particular, which cellular signal mechanisms are regulated by CLAs which can explain their anticancer properties. We have shown that CLAs specifically up-regulate cell signal systems at the level of gene expression (mRNA, protein) in human breast and prostate cancer cells which are responsible for the induction of apoptosis or programmed cell death. These findings support the anticancer effects of CLA found in animal models and indicate similar effects could occur in man.

Coenzyme Q differentially modulates phospholipid hydroperoxide glutathione peroxidase gene expression and free radicals production in malignant and non-malignant prostate cells.

The aim of this study was to investigate the role of coenzyme Q on the mRNA abundance of PHGPx and the reactive oxygen species (ROS) production in two different cell lines from human prostate, a line of non cancer cells (PNT2) and a line of cancer cells (PC3). Results showed that malignant cells markedly differ in their response to coenzyme Q compared to non-malignant cells, with no changes in PHGPx expression and greater ROS production. Furthermore coenzyme Q supplementation significantly lowered cell growth of the PC3 cancer line without affecting the PNT2. If these results are confirmed with additional experiments, it could represent a novel and interesting approach on the biomedical use of coenzyme Q10 in cancer therapy.

Immunonutrition in clinical practice: what is the current evidence?

The clinical trials of immunonutrition that we have undertaken have often been small, single centre studies. They have often been of limited statistical power and have often included patients with a variety of underlying disease states and at different points in the disease process. Three meta-analysis and a consensus statement in conjunction with a systematic review, have been performed in an attempt to overcome many of these limitations and understand further the clinical place for immunonutrition. However, there are still many questions regarding the place of immunonutrition in clinical practice that we still do not understand or have definitive answers to. For example, do we really know what is the optimal combination of nutrients and in what quantities they should be provided? Do we understand any potential interactions that might occur between these nutrients? What is the effect of the patients nutritional state? When and for how long should immunonutrition provided? What is the impact of the patients' underlying disease process and how does this interact with the provision of immunonutrition? At the present time whilst there is some indication and evidence as to which patients might benefit most, and as to those who may not benefit or even suffer detrimental effects from immunonutrition, we still can not answer these questions with any definitive authority. It is essential now that we undertake large well designed, well controlled multicentre studies with adequate statistical power to answer these questions. The indications are that immunonutrition has the potential to help patients but its place must be more clearly defined before its widespread acceptance into clinical practice is based on sound scientific evidence.

Regulation of fatty acid synthase (FAS) and apoptosis in estrogen-receptor positive and negative breast cancer cells by conjugated linoleic acids.

BACKGROUND: Conjugated linoleic acids (CLAs) are natural dairy food components that exhibit a unique body of potential health benefits in animals and man, including anti-cardiovascular disease and anti-cancer effects. Several studies have demonstrated that fatty acid synthase (FAS) levels (protein and mRNA) are over expressed in many carcinomas. Sterol regulatory element binding proteins (SREBPs) are transcription factors that regulate genes involved in lipid metabolism, including FAS. METHODS: Breast cancer cell lines, MCF-7 and MDA-MB-231 were treated with CLAs to investigate the regulation of SREBP-1c and FAS expression. RESULTS: In MDA-MB-231 cells, SREBP-1c and FAS were co-ordinately decreased by treatment with 25 µM CLA 9-11 and 10-12. In MCF-7 cells, the decrease in SREBP-1c and FAS expression was dependant on the concentration of CLA used. CONCLUSIONS: The data suggest a differential effect of CLAs on SREBP-1c and FAS in estrogen receptor-positive (MCF-7) compared to estrogen receptor-negative (MDA-MB-231) breast cancer cells.

Omega-3 N-acylethanolamines are endogenously synthesised from omega-3 fatty acids in different human prostate and breast cancer cell lines.

Omega-3 (n-3) fatty acids inhibit breast and prostate cancer cell growth. We previously showed that N-acylethanolamine derivatives of n-3 (n-3-NAE) are endocannabinoids, which regulate cancer cell proliferation. These n-3-NAE are synthesised in certain cells/tissues, after supplementing with fatty acids, however, no one has assessed whether and to what extent this occurs in cancer cells. We determined levels of endogenous n-3-NAEs in hormone sensitive and insensitive prostate and breast cancer cells and subsequent effects on other endocannabinoids (anandamide and 2-arachidonoylglycerol), before and after supplementing with DHA and EPA fatty acids, using HPLC tandem mass spectrometry. This is the first study reporting that n-3-NAEs are synthesised from their parent n-3 fatty acids in cancer cells, regardless of tumour type, hormone status or the presence of fatty acid amide hydrolase. This could have important implications for the use of n-3 fatty acids as therapeutic agents in breast and prostate cancers expressing cannabinoid receptors.

Effect of Lactobacillus casei on the Production of Pro-Inflammatory Markers in Streptozotocin-Induced Diabetic Rats.

It has been demonstrated that probiotic supplementation has positive effects in several murine models of disease through influences on host immune responses. This study examined the effect of Lactobacillus casei strain Shirota (L. casei Shirota) on the blood glucose, C-reactive protein (CRP), Interleukin-6 (IL-6), Interleukin-4 (IL-4), and body weight among STZ-induced diabetic rats. Diabetes mellitus was induced by streptozotocin (STZ, 50 mg/kg BW) in male Sprague-Dawley rats. Streptozotocin caused a significant increase in the blood glucose levels, CRP, and IL-6. L. casei Shirota supplementation lowered the CRP and IL-6 levels but had no significant effect on the blood glucose levels, body weight, or IL-4. Inflammation was determined histologically. The presence of the innate immune cells was not detectable in the liver of L. casei Shirota-treated hyperglycemic rats. The probiotic L. casei Shirota significantly lowered blood levels of pro-inflammatory cytokines (IL-6, CRP) and neutrophils in diabetic rats, showing a lower risk of diabetes mellitus and its complications.

Impaired expression of glutathione peroxidase-4 gene in peripheral blood mononuclear cells: a biomarker of increased breast cancer risk.

Breast cancer aetiology is unclear despite comprising approximately 28% of female cancers. Several risk factors are known. Not all women exhibiting established risk factors will develop breast cancer but many without recognised risk factors will, indicating involvement of unknown risk factors. Impaired basal or oxidation-stimulated gene expression of redox enzymes, particularly Glutathione Peroxidase 1 and 4 (GPX1 and 4), resulting in increased oxidative stress, could be an "unknown" risk factor in breast cancer. We determined whether basal expression of GPX1 and 4, two major redox enzymes, in Peripheral Blood Mononuclear Cells (PBMNC) and/or their stimulated expression (oxidative stress) was impaired in women with breast cancer who have no known markers of risk compared with control women without breast cancer. A significant 30% impairment (p< 0.01) in basal PBMNC GPX4, but not GPX1, gene expression was observed in cancer patients. Oxidative stress stimulation in vitro did not increase GPX4 expression significantly in cancer patients or control women whereas GPX1 expression was significantly increased (30%, p<0.05) only in the cancer group. Attenuation of GPX4 mRNA expression in PBMNC suggests this could be a simple,early biomarker for future breast cancer risk in the high proportion of women without known risk factors who eventually contract the disease.