Essential polyunsaturated fatty acids, inflammation, atherosclerosis and cardiovascular diseases

Association between circulating levels of unsaturated fatty acids and risk for prediabetes in the NHANES 2003-2004 and 2011-2012

AIMS

This study aimed to investigate the association between serum levels of common and uncommon unsaturated fatty acids and prediabetes risk.

METHODS

Data were collected from the National Health and Nutrition Examination Survey for 2003-2004 and 2011-2012. Weighted proportional and multivariate logistic regression analyses were performed to assess the association of serum PUFAs and MUFAs with prediabetes risk after adjusting for potential confounders.

RESULTS

A total of 3575 individuals were enrolled in this study. Serum levels of PUFAs EPA (20:5 n3) and GLA (18:3 n6) were associated with increased prediabetes risk (EPA (20:5 n3): OR = 1.878, 95% CI: 1.177-2.996, Ptrend = 0.002; GLA (18:3 n6): 1.702, 95% CI: 1.140-2.541, Ptrend = 0.016). The MUFAs PA (16:1 n7) and EA (20:1 n9) were associated with the risk of prediabetes (OR in quintile5: PA (16:1 n7): 1.780, 95% CI: 1.056-3.001, Ptrend = 0.003; EA (20:1 n9): 0.587, 95% CI: 0.347-0.994, Ptrend = 0.010). Moreover, nonlinear analysis revealed that serum levels of EPA (20:5 n3) and EA (20:1 n-9) were nonlinearly associated with prediabetes risk.

CONCLUSION

Some serum n-3 PUFAs are positively associated with prediabetes, several serum n-6 PUFAs are inversely associated with prediabetes. Regulating individual serum USFA levels may help prevent prediabetes, thereby providing evidence for clinical and nutritional practices.

Impact of dietary n-6/n-3 fatty acid ratio of atherosclerosis risk: A review

Atherosclerosis is a causative factor associated with cardiovascular disease (CVD). Over the past few decades, extensive research has been carried out on the relationship between the n-6/n-3 fatty acid ratio of ingested lipids and the progression of atherosclerosis. However, there are still many uncertainties regarding the precise nature of this relationship, which has led to challenges in providing sound dietary advice to the general public. There is therefore a pressing need to review our current understanding of the relationship between the dietary n-6/n-3 fatty acid ratio and atherosclerosis, and to summarize the underlying factors contributing to the current uncertainties. Initially, this article reviews the association between the n-6/n-3 fatty acid ratio and CVDs in different countries. A summary of the current understanding of the molecular mechanisms of n-6/n-3 fatty acid ratio on atherosclerosis is then given, including inflammatory responses, lipid metabolism, low-density lipoprotein cholesterol oxidation, and vascular function. Possible reasons behind the current controversies on the relationship between the n-6/n-3 fatty acid ratio and atherosclerosis are then provided, including the precise molecular structures of the fatty acids, diet-gene interactions, the role of fat-soluble phytochemicals, and the impact of other nutritional factors. An important objective of this article is to highlight areas where further research is needed to clarify the role of n-6/n-3 fatty acid ratio on atherosclerosis.

Anti-pollutant effect of oleic acid against urban particulate matter is mediated via regulation of AhR- and TRPV1-mediated signaling in vitro

Urban Particulate Matter (UPM) induces skin aging and inflammatory responses by regulating skin cells through the transient receptor potential vanilloid 1 (TRPV1). Although oleic acid, an unsaturated free fatty acid (FFA), has some functional activities, its effect on UPM-induced skin damage has not been elucidated. Here, we investigated signaling pathways on how oleic acid is involved in attenuating UPM induced cell damage. UPM treatment increased XRE-promoter luciferase activity and increased translocation of AhR to the nucleus, resulting in the upregulation of CYP1A1 gene. However, oleic acid treatment attenuated the UPM effects on AhR signaling. Furthermore, while UPM induced activation of TRPV1 and MAPKs signaling which activated the downstream molecules NFκB and AP-1, these effects were reduced by cotreatment with oleic acid. UPM-dependent generation of reactive oxygen species (ROS) and reduction of cellular proliferation were also attenuated by the treatment of oleic acid. These data reveal that cell damage induced by UPM treatment occurs through AhR signaling and TRPV1 activation which in turn activates ERK and JNK, ultimately inducing NFκB and AP-1 activation. These effects were reduced by the cotreatment of oleic acid on HaCaT cells. These suggest that oleic acid reduces UPM-induced cell damage through inhibiting both the AhR signaling and activation of TRPV1 and its downstream molecules, leading to a reduction of pro-inflammatory cytokine and recovery of cell proliferation.

Omega-9 fatty acids: potential roles in inflammation and cancer management

Background

Omega-9 fatty acids represent one of the main mono-unsaturated fatty acids (MUFA) found in plant and animal sources. They are synthesized endogenously in humans, though not fully compensating all body requirements. Consequently, they are considered as partially essential fatty acids. MUFA represent a healthier alternative to saturated animal fats and have several health benefits, including anti-inflammatory and anti-cancer characters.

The main body of the abstract

This review capitalizes on the major omega-9 pharmacological activities in context of inflammation management for its different natural forms in different dietary sources. The observed anti-inflammatory effects reported for oleic acid (OA), mead acid, and erucic acid were directed to attenuate inflammation in several physiological and pathological conditions such as wound healing and eye inflammation by altering the production of inflammatory mediators, modulating neutrophils infiltration, and altering VEGF effector pathway. OA action mechanisms as anti-tumor agent in different cancer types are compiled for the first time based on its anti- and pro-carcinogenic actions.

Conclusion

We conclude that several pathways are likely to explain the anti-proliferative activity of OA including suppression of migration and proliferation of breast cancer cells, as well stimulation of tumor suppressor genes. Such action mechanisms warrant for further supportive clinical and epidemiological studies to confirm the beneficial outcomes of omega-9 consumption especially over long-term intervention.

Association of Dietary Nutrient Intake with Early Age-Related Macular Degeneration in Japanese-Americans

Lifestyle factors may be associated with the development of age-related macular degeneration (AMD), in addition to demographic and genetic factors. The purpose of this cross-sectional study is to elucidate the association between nutrient intake and AMD in the Japanese-American population living in Los Angeles. We conducted a medical survey of Japanese immigrants and their descendants living in Los Angeles, including interviews on dietary habits, fundus photography, and physical examinations. Participants were classified into early AMD and control groups on the basis of fundus photographic findings. Consequently, among the 555 participants, 111 (20.0%) were diagnosed with early AMD. There were no late-stage AMD participants. Multivariate logistic regression analysis showed that the intake of animal fat and saturated fatty acids (SFA) was positively associated with early AMD (p for trend = 0.01 for animal fat, p for trend = 0.02 for SFA), and the intake of vegetable fat, total carbohydrate, simple carbohydrate, sugar, and fructose was inversely associated with early AMD (p for trend = 0.04 for vegetable fat, p for trend = 0.046 for carbohydrate, p for trend = 0.03 for simple carbohydrate, p for trend = 0.046 for sugar, p for trend = 0.02). Our findings suggest that excessive animal fat and SFA intake increases the risk for early AMD in Japanese-Americans whose lifestyles have been westernized.

The Short Overview on the Relevance of Fatty Acids for Human Cardiovascular Disorders

This review presents existing evidence of the influence of saturated and unsaturated fatty acids on cardiovascular diseases (CVD). Data are discussed regarding the roles of the most relevant fatty acids, such as myristic (C14:0), palmitic (C16:0), stearic (C18:0), palmitoleic (C16:1), oleic (C18:1), linoleic (C18:2), α-linolenic (C18:3, ω-3), γ-linolenic (C18:3, ω-6), arachidonic (C20:4), eicosapentaenoic (C20:5), docosahexaenoic (C22:6), and docosapentaenoic (C22:5) acid. The accumulated knowledge has expanded the understanding of the involvement of fatty acids in metabolic processes, thereby enabling the transition from basic exploratory studies to practical issues of application of these biomolecules to CVD treatment. In the future, these findings are expected to facilitate the interpretation and prognosis of changes in metabolic lipid aberrations in CVD.

The Role of Nutri(epi)genomics in Achieving the Body's Full Potential in Physical Activity

Physical activity represents a powerful tool to achieve optimal health. The overall activation of several molecular pathways is associated with many beneficial effects, mainly converging towards a reduced systemic inflammation. Not surprisingly, regular activity can contribute to lowering the “epigenetic age”, acting as a modulator of risk toward several diseases and enhancing longevity. Behind this, there are complex molecular mechanisms induced by exercise, which modulate gene expression, also through epigenetic modifications. The exercise-induced epigenetic imprint can be transient or permanent and contributes to the muscle memory, which allows the skeletal muscle adaptation to environmental stimuli previously encountered. Nutrition, through key macro- and micronutrients with antioxidant properties, can play an important role in supporting skeletal muscle trophism and those molecular pathways triggering the beneficial effects of physical activity. Nutrients and antioxidant food components, reversibly altering the epigenetic imprint, have a big impact on the phenotype. This assigns a role of primary importance to nutri(epi)genomics, not only in optimizing physical performance, but also in promoting long term health. The crosstalk between physical activity and nutrition represents a major environmental pressure able to shape human genotypes and phenotypes, thus, choosing the right combination of lifestyle factors ensures health and longevity.

Relationship between high-sensitivity C-reactive protein and subclinical carotid atherosclerosis stratified by glucose metabolic status in Chinese adults

BACKGROUND

Atherosclerosis is an inflammatory disease. Many studies demonstrated that hyperglycemia is not only increased inflammatory response, but also is a cause of atherosclerosis, implying that glucose metabolic status may be an important stratification factor when analyzing the relationship between inflammatory levels and subclinical carotid atherosclerosis. The aim of the present study is to assess the relationship between inflammatory levels and subclinical carotid atherosclerosis, stratified by different glucose metabolic status in a general population.

METHODS

An assessment was performed in 7975 participants living in Tianjin, China. In the present study, we examined subclinical carotid atherosclerosis, as defined by increased carotid intima-media thickness [IMT] and plaques. Measurements were performed using a carotid artery B-mode ultrasound system. The glucose metabolic status was defined by the criteria of the American Diabetes Association, and high-sensitivity C-reactive protein (hs-CRP) as an inflammatory indicator, was measured by immunoturbidimetric assay. Multiple logistic models were used to assess a stratified relationship between hs-CRP levels and subclinical carotid atherosclerosis. Strata were defined according to glucose metabolic status.

RESULTS

The prevalence of increased IMT and plaques were 27.3% and 21.3%, respectively. The adjusted odds ratios (95% confidence interval) for IMT across hs-CRP quartiles were as follows: 1.00 (reference), 1.10(0.88-1.38), 1.08(0.86-1.35) and 1.32(1.06-1.66) in blood glucose-normal subjects; 1.00 (reference), 1.33(0.92-1.91), 1.33(0.93-1.91), and 1.59(1.10-2.30) in prediabetic subjects; 1.00 (reference), 0.94(0.54-1.62), 1.17(0.65-2.12) and 0.98(0.55-1.76) in diabetic subjects, respectively. Similar results were observed for plaques.

CONCLUSIONS

Our results suggest that inflammatory levels are differently related to subclinical carotid atherosclerosis by the different glucose metabolic status.

Berberine protects myocardial cells against anoxia-reoxygenation injury via p38 MAPK-mediated NF-κB signaling pathways

Ischemic heart disease is a leading cause of mortality and occurs due to coronary arterial atherosclerosis, vascular cavity stenosis and occlusion. It has previously been demonstrated that berberine treatment may ameliorate and help to prevent cardiovascular diseases due to its anti-inflammatory and anti-apoptotic effects in myocardial cells. However, the potential signaling mechanisms mediated by berberine in the progression of myocardial injury remain to be elucidated. The aim of the present study was to investigate the therapeutic effects of berberine and its potential mechanism in a mouse model of myocardial cell injury. The results revealed that berberine treatment downregulated the serum expression of inflammatory factors, including interleukin (IL)-6, tumor necrosis factor-α, IL-10 and IL-17A in mice with anoxia-reoxygenation injury. Berberine treatment also decreased myocardial cell apoptosis following anoxia-reoxygenation injury via regulating the expression of apoptosis-associated genes. Histological analysis revealed that the area, circumference fragmentation and segmentation of myocardial cells were significantly decreased by berberine treatment compared with the control group. The body weight, blood lipid levels, blood pressure and heart rate were markedly improved in mice with anoxia-reoxygenation injury following berberine treatment compared with untreated mice. The expression of p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-κB expression was downregulated in myocardial cells from in mice with anoxia-reoxygenation injury following berberine treatment compared with untreated mice. However, p38 MAPK overexpression ameliorated the berberine-induced decrease in NF-κB activity and expression, as well as the berberine-induced inhibition of myocardial apoptosis in myocardial cells isolated from experimental mice. In conclusion, the results of the present study indicate that berberine is able to decrease the expression of inflammatory cytokines expression and inhibit myocardial cell apoptosis via downregulating the p38 MAPK-mediated NF-κB signaling pathway. These results suggest that berberine may be an effective treatment for anoxia-reoxygenation injury.

A new perspective on lipid research in age-related macular degeneration

There is an urgency to find new treatment strategies that could prevent or delay the onset or progression of AMD. Different classes of lipids and lipoproteins metabolism genes have been associated with AMD in a multiple ways, but despite the ever-increasing knowledge base, we still do not understand fully how circulating lipids or local lipid metabolism contribute to AMD. It is essential to clarify whether dietary lipids, systemic or local lipoprotein metabolismtrafficking of lipids in the retina should be targeted in the disease. In this article, we critically evaluate what has been reported in the literature and identify new directions needed to bring about a significant advance in our understanding of the role for lipids in AMD. This may help to develop potential new treatment strategies through targeting the lipid homeostasis.

Docosahexaenoic acid (DHA) at the sn-2 position of triacylglycerols increases DHA incorporation in brown, but not in white adipose tissue, of hamsters

We hypothesised that the incorporation of docosahexaenoic acid (DHA) across adipose tissues will be higher when it is ingested as triacylglycerols (TAG) structured at the sn-2 position. Ten-week old male hamsters were allocated to 4 dietary treatments (n = 10): linseed oil (LSO-control group), fish oil (FO), fish oil ethyl esters (FO-EE) and structured DHA at the sn-2 position of TAG (DHA-SL) during 12 weeks. In opposition to the large variations found for fatty acid composition in retroperitoneal white adipose tissue (WAT), brown adipose tissue (BAT) was less responsive to diets. DHA was not found in subcutaneous and retroperitoneal WAT depots but it was successfully incorporated in BAT reaching the highest percentage in DHA-SL. The PCA on plasma hormones (insulin, leptin, adiponectin) and fatty acids discriminated BAT from WATs pointing towards an individual signature on fatty acid deposition, but did not allow for full discrimination of dietary treatments within each adipose tissue.

Circulating Omega-6, But Not Omega-3 Polyunsaturated Fatty Acids, Are Associated with Clinical Outcomes in Patients with Acute Decompensated Heart Failure

Background

Circulating polyunsaturated fatty acid (PUFA) levels are associated with clinical outcomes in cardiovascular diseases including coronary artery disease and chronic heart failure (HF). However, their clinical implications in acute decompensated HF (ADHF) remain unclear. The aim of this study was to investigate the clinical roles of circulating PUFAs in patients with ADHF.

Methods

Circulating levels of PUFAs, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA) and dihomo-gamma linoleic acid (DGLA), were measured on admission in 685 consecutive ADHF patients. Adverse events were defined as all-cause death and worsening HF.

Results

During a median follow-up period of 560 days, 262 (38.2%) patients had adverse events. Although patients with adverse events had lower n-6 PUFA (AA + DGLA) level than those without, n-3 PUFA (EPA + DHA) level was comparable between the groups. Kaplan-Meier analyses showed that lower n-6 PUFA level on admission was significantly associated with the composite of all-cause death and worsening HF, all-cause death, cardiovascular death and worsening HF (p < 0.001, p = 0.005, p = 0.021, p = 0.019, respectively). In a multivariate Cox model, lower n-6 PUFA level was independently associated with increased risk of adverse events (HR 0.996, 95% CI: 0.993–0.999, p = 0.027).

Conclusions

Lower n-6 but not n-3 PUFA level on admission was significantly related to worse clinical outcomes in ADHF patients. Measurement of circulating n-6 PUFA levels on admission might provide information for identifying high risk ADHF patients.

Reduction of Platelet Aggregation From Ingestion of Oleic and Linoleic Acids Found in Vitis vinifera and Arachis hypogaea Oils

The purpose of this study was to evaluate the effect of the consumption of seed oils from Vitis vinifera and Arachis hypogaea in platelet aggregation. The initial hypothesis suggested that subjects who have consumed these seed oils undergo modified platelet aggregation. This study was performed using a pre-post test design, with a control group, and double blind. The effects of the consumption of grape seed and peanut oils were measured for platelet aggregation in clinical and laboratory tests in 30 healthy subjects. In addition to this group, a control group of 4 health subjects received no treatment with oils, just 500 mg oral administration acetylsalicylic acid for 7 days. Platelet aggregation was assessed by the Born turbidimetric method, using 3 different concentrations of adenosine diphosphate as agonists (2, 54; 1, 17; and 0, 58 μM). The study subjects had very similar results; both oils were shown to have a significant reduction in platelet aggregation. Grape seed oil showed a decrease of 8.4 ± 1% in aggregation, compared with peanut oil, which decreased aggregation by 10.4 ± 1%. The control group, taking 500 mg OD aspirin for 7 days, showed a significant decrease in platelet aggregation, similar to that of oil ingestion. Each of the oils was analyzed for fatty acids, to determine which particular acids were presents in greater levels, which could explain the reduction in platelet aggregation. The oil found to be most abundant in grape seeds was linoleic acid (omega-6), and in peanuts, it was oleic acid (omega-9). However, in fact, both acids reduced platelet aggregation. Consumption of plant oils from grape seeds and peanuts had a lowering effect on platelet aggregation, in addition to containing a high content of unsaturated fatty acids. However, omega-3, omega-6, and omega-9 fatty acids were not specifically responsible for the reductions mentioned above.

Oleic acid promotes adaptability against oxidative stress in 3T3-L1 cells through lipohormesis

Although fatty acids are important components of biological membranes, energy sources, and signal transducers or precursors of lipid mediators, excess intake of fatty acids and their accumulation cause obesity and metabolic syndrome. Thus, fatty acid quantity is known to be an important factor for obesity-related diseases, but the effects of different types of fatty acids (i.e., fatty acid quality) on human health are not completely understood. We here focused on the relationship between fatty acid quality and oxidative stress by investigating whether resistibility to tert-butyl hydrperoxide (t-BuOOH)-induced oxidative stress in 3T3-L1 cells varied according to the fatty acid type. Among eight fatty acids (both saturated and unsaturated) tested, oleic acid (OA) exerted the most pronounced cytoprotective effects, with efficacy over a wide range of concentrations. OA treatment markedly enhanced the intracellular levels of lipid peroxidation markers, including N(ε)-(hexanoyl)lysine, 4-hydroxy-2-nonenal, and acrolein. The levels of these markers in OA-treated cells were decreased after t-BuOOH exposure, whereas the levels in untreated control cells were notably increased after t-BuOOH exposure. Our results suggested that unsaturated fatty acids, particularly OA, could promote an adaptive response and enhance cell tolerance through increased cellular antioxidative capacity via OA-induced mild lipid peroxidation (lipohormesis), and thus protect cells against subsequent oxidative stress-related injury.

Influence of physical activity and nutrition on obesity-related immune function

Research examining immune function during obesity suggests that excessive adiposity is linked to impaired immune responses leading to pathology. The deleterious effects of obesity on immunity have been associated with the systemic proinflammatory profile generated by the secretory molecules derived from adipose cells. These include inflammatory peptides, such as TNF- α , CRP, and IL-6. Consequently, obesity is now characterized as a state of chronic low-grade systemic inflammation, a condition considerably linked to the development of comorbidity. Given the critical role of adipose tissue in the inflammatory process, especially in obese individuals, it becomes an important clinical objective to identify lifestyle factors that may affect the obesity-immune system relationship. For instance, stress, physical activity, and nutrition have each shown to be a significant lifestyle factor influencing the inflammatory profile associated with the state of obesity. Therefore, the purpose of this review is to comprehensively evaluate the impact of lifestyle factors, in particular psychological stress, physical activity, and nutrition, on obesity-related immune function with specific focus on inflammation.

Omega-3 fatty acids inhibit tumor growth in a rat model of bladder cancer

Omega-3 (ω-3) fatty acids have been tested on prevention and treatment of several cancer types, but the efficacy on “in vivo” bladder cancer has not been analyzed yet. This study aimed at evaluating the chemopreventive efficacy of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) mixture in an animal model of bladder cancer. Forty-four male Wistar rats were divided into 4 groups during a 20-week protocol: control; carcinogen—N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN); ω-3 (DHA + EPA); and ω-3 + BBN. BBN and ω-3 were given during the initial 8 weeks. At week 20 blood and bladder were collected and checked for the presence of urothelium lesions and tumors, markers of inflammation, proliferation, and redox status. Incidence of bladder carcinoma was, control (0%), ω-3 (0%), BBN (65%), and ω-3 + BBN (62.5%). The ω-3 + BBN group had no infiltrative tumors or carcinoma in situ, and tumor volume was significantly reduced compared to the BBN (0.9 ± 0.1 mm³ versus 112.5 ± 6.4 mm³). Also, it showed a reduced MDA/TAS ratio and BBN-induced serum CRP, TGF-β1, and CD31 were prevented. In conclusion, omega-3 fatty acids inhibit the development of premalignant and malignant lesions in a rat model of bladder cancer, which might be due to anti-inflammatory, antioxidant, anti-proliferative, and anti-angiogenic properties.

Prevention of postoperative atrial fibrillation in open heart surgery patients by preoperative supplementation of n-3 polyunsaturated fatty acids: an updated meta-analysis

BACKGROUND

Several randomized clinical trials evaluated whether preoperative supplementation of omega-3 (n-3) polyunsaturated fatty acids protects against postoperative atrial fibrillation after cardiac surgery, a condition associated with increased cardiac and cerebral mortality. However, their efficacy remains still controversial. An updated meta-analysis was performed to clarify if preoperative n-3 polyunsaturated fatty acid supplementation prevents postoperative atrial fibrillation in patients undergoing cardiac surgery.

METHODS

Articles were retrieved until November 2012 by screening electronic databases (PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials) and cross references. Two of us independently reviewed articles and agreed to select 8 randomized clinical trials. For each study, the incidence of atrial fibrillation in both the intervention and placebo groups was extracted to calculate odd ratio and 95% confidence intervals (CIs). Weighted study-specific estimates were combined using fixed (Mantel-Haenszel method) and random-effects (DerSimonian-Laird method) models.

RESULTS

This meta-analysis includes 2687 patients (1337 in the intervention group) who underwent cardiac surgery. Pooled analysis using fixed-effects models showed a significant reduction (average, 16%; 95% CI, 1%-29%) in postoperative atrial fibrillation by preoperative n-3 polyunsaturated fatty acids. There was a low heterogeneity among studies (P = .07 and I(2) = 46%). By using a random-effects model, the reduction averaged 25% (odds ratio, 0.75; 95% CI, 0.57-1.00; P = .05). When isolated coronary artery bypass graft surgery was only considered (7 studies), a significant protection averaging 34% was observed in a fixed model (odds ratio, 0.66; 95% CI, 0.50-0.87; P = .003; I(2) = 26%, P = .23).

CONCLUSIONS

A preoperative supplementation of n-3 polyunsaturated fatty acids significantly prevents the occurrence of postoperative atrial fibrillation in patients undergoing cardiac surgery, in particular coronary artery bypass surgery.

Effect of dietary linoleic acid on markers of inflammation in healthy persons: a systematic review of randomized controlled trials

The majority of evidence suggests that n-6 polyunsaturated fatty acids, including linoleic acid (LA), reduce the risk of cardiovascular disease as reflected by current dietary recommendations. However, concern has been expressed that a high intake of dietary n-6 polyunsaturated fatty acid contributes to excess chronic inflammation, primarily by prompting the synthesis of proinflammatory eicosanoids derived from arachidonic acid and/or inhibiting the synthesis of anti-inflammatory eicosanoids from eicosapentaenoic and/or docosahexaenoic acids. A systematic review of randomized controlled trials that permitted the assessment of dietary LA on biologic markers of chronic inflammation among healthy noninfant populations was conducted to examine this concern. A search of the English- and non-English-language literature using MEDLINE, the Cochrane Controlled Trials Register, and EMBASE was conducted to identify relevant articles. Fifteen studies (eight parallel and seven crossover) met inclusion criteria. None of the studies reported significant findings for a wide variety of inflammatory markers, including C-reactive protein, fibrinogen, plasminogen activator inhibitor type 1, cytokines, soluble vascular adhesion molecules, or tumor necrosis factor-α. The only significant outcome measures reported for higher LA intakes were greater excretion of prostaglandin E2 and lower excretion of 2,3-dinor-thromboxane B(2) in one study and higher excretion of tetranorprostanedioic acid in another. However, the authors of those studies both observed that these effects were not an indication of increased inflammation. We conclude that virtually no evidence is available from randomized, controlled intervention studies among healthy, noninfant human beings to show that addition of LA to the diet increases the concentration of inflammatory markers.

Polyunsaturated fatty acids confer cryoresistance on megakaryocytes generated from cord blood and also enhance megakaryocyte production from cryopreserved cord blood cells

BACKGROUND AIMS

Previous data have shown that the addition of docosahexanoic acid (DHA)/arachidonic acid (AA) has a beneficial effect on cytokine-mediated in vitro generation of megakaryocytes (MK) from umbilical cord blood (UCB).Cryopreservation forms an inherent part of UCB banking and MK progenitors are known to be very sensitive to the stresses of freezing. It is therefore imperative to generate functional cells from cryopreserved cells, and the generated cells need to be cryopreserved until used. In the present study, cryopreservation of ex vivo-expanded MK as well as MK generation from cryopreserved UCB samples was investigated.

METHODS

MK generated with or without DHA/AA were cryopreserved in freezing medium containing 10% dimethyl sulfoxide (DMSO). Freezing efficacy was tested by quantitating MK after revival. Cryopreserved CD34(+) cells were cultured with stem cell factor (SCF) and thrombopoietin (TPO), in the presence and absence of DHA/AA for 10 days, and then quantitated for MK. Results. We observed a 1.5-3-fold increase in MK numbers, their progenitor content and their expression of phenotypic markers and MK-related transcription factors. DHA/AA sets showed a 2-5-fold improved engraftment in NOD/SCID mice. These data showed that the beneficial effect of DHA/AA obtained during MK expansion was not altered after freezing stress. The enhancement in MK generation obtained from fresh cord blood (CB) cells was reproduced with comparable efficiency when we used cryopreserved CB samples.

CONCLUSIONS

Taken together, our data suggest that in vitro-generated DHA/AA MK survive cryoinjuries in a functionally better state. DHA/AA support a more efficient generation of MK from cryopreserved UCB.

Diet and inflammation

The emerging role of chronic inflammation in the major degenerative diseases of modern society has stimulated research into the influence of nutrition and dietary patterns on inflammatory indices. Most human studies have correlated analyses of habitual dietary intake as determined by a food frequency questionnaire or 24-hour recall with systemic markers of inflammation like high-sensitivity C-reactive protein (HS-CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). An occasional study also includes nutrition analysis of blood components. There have been several controlled interventions which evaluated the effect of a change in dietary pattern or of single foods on inflammatory markers in defined populations. Most studies reveal a modest effect of dietary composition on some inflammatory markers in free-living adults, although different markers do not vary in unison. Significant dietary influences have been established for glycemic index (GI) and load (GL), fiber, fatty acid composition, magnesium, carotenoids, and flavonoids. A traditional Mediterranean dietary pattern, which typically has a high ratio of monounsaturated (MUFA) to saturated (SFA) fats and ω-3 to ω-6 polyunsaturated fatty acid (PUFAs) and supplies an abundance of fruits, vegetables, legumes, and grains, has shown anti-inflammatory effects when compared with typical North American and Northern European dietary patterns in most observational and interventional studies and may become the diet of choice for diminishing chronic inflammation in clinical practice.

High-density lipoprotein metabolism in human apolipoprotein B(100) transgenic/brown adipose tissue deficient mice: a model of obesity-induced hyperinsulinemia

Obese and diabetic humans display decreased plasma high-density lipoprotein cholesterol (HDL-C) concentrations and an increased risk for coronary heart disease. However, investigation on HDL metabolism in obesity with a particular emphasis on hepatic ATP-binding cassette transporter A1 (ABCA1), the primary factor for HDL formation, has not been well studied. Human apolipoprotein B(100) transgenic (hApoB(tg)) and brown adipose tissue deficient (BATless) mice were crossed to generate hApoB(tg)/BATless mice. Male and female hApoB(tg) and hApoB(tg)/BATless mice were maintained on either a regular rodent chow diet or a diet high in fat and cholesterol until 24 weeks of age. The hApoB(tg)/BATless mice that were fed a HF/HC diet became obese, developed hepatic steatosis, and had significantly elevated plasma insulin levels compared with their hApoB(tg) counterparts, but plasma concentrations of total cholesterol, HDL-C, triglycerides, and free fatty acids and lipoprotein distribution between genotypes were not significantly different. Hepatic expression of genes encoding HDL-modifying factors (e.g., scavenger receptor, class B, type I, hepatic lipase, lecithin:cholesterol acyltransferase, and phospholipid transfer protein) was either altered significantly or showed a trend of difference between 2 genotypes of mice. Importantly, hepatic protein levels of ABCA1 were significantly lowered by ∼35% in male obese hApoB(tg)/BATless mice with no difference in mRNA levels compared with hApoB(tg) counterparts. Despite reduced hepatic ABCA1 protein levels, plasma HDL-C concentrations were not altered in male obese hApoB(tg)/BATless mice. The result suggests that hepatic ABCA1 may not be a primary contributing factor for perturbations in HDL metabolism in obesity-induced hyperinsulinemia.

Oleic acid modulation of the immune response in wound healing: a new approach for skin repair

Injury triggers inflammatory responses and tissue repair. Several treatments are currently in use to accelerate healing; however, more efficient formulations are still needed for specific injuries. Since unsaturated fatty acids modulate immune responses, we aimed to evaluate their therapeutic effects on wound healing. Skin wounds were induced in BALB/c mice and treated for 5 days with n-3, n-9 fatty acids or vehicle (control). n-9 treated mice presented smaller wounds than control and n-3 at 120 h post-surgery (p.s.). Collagen III mRNA, TIMP1 and MMP9 were significantly elevated in n-9 group compared to n-3 or vehicle at 120 h p.s. Among the inflammatory mediators studied we found that IL-10, TNF-α and IL-17 were also higher in n-9 treated group compared to n-3 or vehicle at 120 h p.s. Interestingly, COX2 had decreased expression on wound tissue treated with n-9. Inflammatory infiltrate analysis revealed diminished frequency of CD4(+), CD8(+) and CD11b(+) cells in n-9 wounds at 24 and 120 h p.s., which was not related to cell death, since in vitro apoptosis experiments did not show any cell damage after fatty acids administration. These results suggested that unsaturated fatty acids, specifically n-9, modulate the inflammation in the wound and enhance reparative response in vivo. n-9 may be a useful tool in the treatment of cutaneous wounds.

Enhanced generation of megakaryocytes from umbilical cord blood-derived CD34(+) cells expanded in the presence of two nutraceuticals, docosahexanoic acid and arachidonic acid, as supplements to the cytokine-containing medium

BACKGROUND AIMS

Ex vivo generation of megakaryocytes (MK) from hematopoietic stem cells (HSC) is important for both basic research, to understand the mechanism of platelet biogenesis, and clinical infusions, for rapid platelet recovery in thrombocytopenic patients. We investigated the role of two nutraceuticals, docosahexanoic acid (DHA) and arachidonic acid (AA), in the in vitro generation of MK.

METHODS

Umbilical cord blood (UCB)-derived CD34+cells were cultured with stem cell factor (SCF) and thrombopoietin (TPO) in the presence (test) or absence (control) of the two additives. On day 10, MK and platelets generated were quantitated by morphologic, phenotypic and functional assays.

RESULTS

The cell yield of MK and platelet numbers were significantly higher in test compared with control cells. Phenotypic analyzes and gene expression profiles confirmed these findings. Functional properties, such as colony-forming unit (CFU)-MK formation, chemotaxis and platelet activation, were found to be enhanced in cells cultured with nutraceuticals. The engraftment potential of ex vivo-expanded cells was studied in NOD/SCID mice. Mice that received MK cultured in the presence of DHA/AA engrafted better. There was a reduction in apoptosis and total reactive oxygen species (ROS) levels in the CD41(+) compartment of the test compared with control sets. The data suggest that these compounds probably exert their beneficial effect by modulating apoptotic and redox pathways.

CONCLUSIONS

Use of nutraceuticals like DHA and AA may prove to be a useful strategy for efficient generation of MK and platelets from cord blood cells, for future use in clinics and basic research.

Association between dietary fat intake and age-related macular degeneration in the Carotenoids in Age-Related Eye Disease Study (CAREDS): an ancillary study of the Women's Health Initiative

OBJECTIVE

To evaluate the relationships between the amount and type of dietary fat and intermediate age-related macular degeneration (AMD).

DESIGN

Women aged 50 to 79 years with high and low lutein intake from 3 sites of the Women's Health Initiative Observational Study were recruited into the Carotenoids in Age-Related Eye Disease Study. Fat intake from 1994 through 1998 was estimated using food frequency questionnaires, and AMD was assessed photographically from 2001 through 2004.

RESULTS

Intakes of omega-6 and omega-3 polyunsaturated fatty acids, which were highly correlated (r = 0.8), were associated with approximately 2-fold higher prevalence of intermediate AMD in high vs low quintiles. However, monounsaturated fatty acid intake was associated with lower prevalence. Age interactions were often observed. In women younger than 75 years (n = 1325), total fat and saturated fatty acid intakes were associated with increased prevalence of AMD (multivariate adjusted odds ratios [95% confidence interval] for intermediate AMD, 1.7 [1.0-2.7] for quintile 5 vs quintile 1 for total fat [P = .10 for trend] and 1.6 [0.7-3.6] for saturated fatty acids [P = .23 for trend]). The associations were reversed in older women.

CONCLUSIONS

These results support a growing body of evidence suggesting that diets high in several types of fat may contribute to the risk of intermediate AMD and that diets high in monounsaturated fatty acids may be protective.

Site specific delivery of microencapsulated fish oil to the gastrointestinal tract of the rat

The aim of this study was to design food grade matrices to deliver microencapsulated fish oil to the large bowel of the rat where the potential exists to retard inflammation and cancer development. Digestion in simulated gastric fluid and intestinal fluid demonstrated that only 4-6% of oil was released from the following dried emulsion formulations: 50% fish oil encapsulated in heated casein-glucose-dried glucose syrup (1:1:1) (Cas-Glu-DGS-50); 25% fish oil in casein-modified resistant starch (Hylon VII) (1:1) (Cas-Hylon-25); or 25% fish oil in Cas-Glu-Hylon (1:1:1) (Cas-Glu-Hylon-25). A short-term gavage study (0-12 h) with fish oil and Cas-Glu-DGS-50 demonstrated the appearance of fish oil long chain (LC) n-3 polyunsaturated fatty acids (PUFA) into the plasma indicating specific small intestinal absorption with little LC n-3 PUFA reaching the large bowel. In a 2-week-long term, daily gavage study, the bioavailability of fish oil and fish oil in Cas-Glu-DGS-50 or Cas-Hylon-25 demonstrated that fish oil and Cas-Glu-DGS-50 LC n-3 PUFA were incorporated into the tissue of the small intestine and colon, whereas Cas-Hylon-25 was resistant to degradation in the small intestine. The use of modified Hylon VII for targeted colonic delivery was confirmed in the final short-term gavage study (0-14 h) using Cas-Glu-Hylon-25 with [(14)C]-trilinolenin as a marker incorporated into the microcapsules, where up to 60% of the labeled oil reached the large bowel. Depending on the microencapsulating matrix employed, fish oil can be delivered selectively to the small intestine or to a high degree to the large bowel.

Interactions of wine drinking with omega-3 fatty acids in patients with coronary heart disease: a fish-like effect of moderate wine drinking

BACKGROUND

Moderate alcohol drinking and marine omega-3 fatty acids (omega3) have both been associated with low mortality from coronary heart disease (CHD). However, there is little data evaluating the interactions of wine ethanol drinking with omega3 in CHD patients.

METHODS

The relationships between wine drinking and marine omega3 were evaluated in a cross-sectional study in patients with CHD participating in a randomized trial testing the effect of a high alpha-linolenic acid (ALA, the main plant omega3) diet. Daily ethanol intake was calculated as energy and expressed as a percentage of total energy. Plant and marine omega3 in the diet were carefully evaluated in each patient in both groups.

RESULTS

Patients were classified according to their habitual consumption of ethanol. Patients in the "high ALA group" and controls ("low ALA group") were analyzed separately. Within each group, there was a progressive increase in marine omega3 levels with increased alcohol intake, with a level of eicosapentanoic acid (EPA) that increased by 50% (P < .005) and 37% (P < .05) in the low and high ALA groups, respectively. After controlling for potential confounders (including dietary EPA) in a multivariate linear model, the association between wine ethanol and EPA remained significant in the low (P < .001) and high (P < .05) ALA groups.

CONCLUSION

In these patients with CHD, moderate wine drinking was associated with higher marine omega3 concentrations than no alcohol use. Although the data have to be confirmed in large groups, this effect of wine comparable to that of fish may partly explain the protective effects of wine drinking against CHD.