An introduction to dietary/supplemental omega-3 fatty acids for general health and prevention: Part II

Impact of Modern Oven Treatments on Lipid Oxidation and Vitamin E Content of Fillets from Sardine (Sardina pilchardus) at Different Reproductive Cycle Phases

The beneficial effects of sardine consumption can be related to the presence of bioactive compounds, such as vitamin E and ω3 polyunsaturated fatty acids. In any case, the levels of these compounds in sardine fillet depend on different factors mainly related to the diet and reproductive cycle phase of the fish as well as the technological treatments carried out to cook the fillets. The aim of the present study is two-fold: first, to evaluate changes in the total fatty acid profile, lipid oxidation, and vitamin E content of raw fillets from sardine (Sardina pilchardus) at different reproductive cycle phases (pre-spawning, spawning, and post-spawning); and second, to highlight how these nutritional profiles are affected by three oven treatments (conventional, steam, and sous-vide). For this purpose, raw fish was grouped into pre-spawning, spawning, and post-spawning phases according to the mesenteric fat frequency and the gonadosomatic index evaluation, and submitted to conventional (CO), steam (SO), and sous-vide (SV) baking. The ratio of EPA/DHA and vitamin E increased from post-spawning to pre-spawning, to spawning. Considering the reproductive phases, baking affected the oxidative degree differently: a CO > SO ≥ SV impact was found in the worst scenario (post-spawning), mitigated by vitamin E, to CO ≥ SO > SV in the best scenario (spawning). SV was the best treatment with high values of vitamin E in pre-spawning individuals (110.1 mg/kg). This study shows how vitamin E is correlated to the combined effect of endogenous and exogenous factors.

Formation of Self-Assembled Liquid Crystalline Nanoparticles and Absorption Enhancement of Ω-3s by Phospholipids and Oleic Acids

This study aimed to optimize and evaluate self-assembled liquid crystalline nanoparticles (SALCs) prepared from phospholipids and oleic acid for enhancing the absorption of Ω-3s. We explored the structure and optimal formulation of SALCs, which are composed of Ω-3 ethyl ester (Ω-3 EE), phospholipids, and oleic acid, using a ternary diagram and evaluated the improvement in Ω-3 dissolution, permeation, and oral bioavailability. The in vitro dissolution and pharmacokinetics of Ω-3 SALCs were compared with those of Omacor soft capsules (as the reference). The shape of the liquid crystal was determined according to the composition of phospholipids, oleic acids, and Ω-3s and was found to be in cubic, lamellar, and hexagonal forms. The dissolution rates of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) obtained from Ω-3 SALCs were 1.7 to 2.3-fold higher than those of the Omacor soft capsules. Furthermore, a pharmacokinetic study in male beagle dogs revealed that Ω-3 SALCs increased the oral bioavailability of Ω-3 EE by 2.5-fold for EPA and 3.1-fold for DHA compared with the reference. We found an optimal formulation that spontaneously forms liquid crystal-based nanoparticles, improving the bioavailability of EPA and DHA, not found in the existing literature. Our findings offer insight into the impact of nanoparticle phase on the oral delivery of oil-soluble drugs and provide a novel Ω-3 EE formulation that improves the bioavailability of EPA and DHA.

Docosahexaenoic acid inhibits zymogen activation by suppressing vacuolar ATPase activation in cerulein-stimulated pancreatic acinar cells

BACKGROUND

The premature activation of digestive enzyme zymogens within pancreatic acinar cells is an important early feature of acute pancreatitis. Supraphysiological concentrations of cholecystokinin (CCK) cause intrapancreatic zymogen activation and acute pancreatitis. Stimulation of vacuolar ATPase (vATPase) activity is required for zymogen activation in pancreatic acinar cells. Parkin, a multiprotein E3 ubiquitin ligase complex, promotes vATPase ubiquitination and degradation, which inhibits vATPase activity. Docosahexaenoic acid (DHA), an omega-3 fatty acid, exerts anti-inflammatory effects. It is reported to bind to G-protein coupled receptor 120 (GPR120) and GPR40. DHA induces the degradation of certain proteins by activating ubiquitin-proteasome system in various cells. This study aimed to investigate whether DHA induces Parkin and inhibits vATPase activity, resulting in zymogen inactivation in pancreatic acinar AR42J cells stimulated with cerulein, a CCK analog.

RESULTS

Cerulein induced the translocation of the cytosolic V1 domain (E subunit) of vATPase to the membrane, which indicated vATPase activation, and zymogen activation in AR42J cells. DHA suppressed the association of the vATPase with membranes, and zymogen activation (increased trypsin activity and amylase release) induced by cerulein. Pretreatment with a GPR120 antagonist AH-7614, a GPR40 antagonist DC260126, or an ubiquitination inhibitor PYR-41 reduced the effect of DHA on cerulein-induced zymogen activation. Treatment with PYR-41 reversed the DHA-induced decrease in vATPase activation in cerulein-treated cells. Furthermore, DHA increased the level of Parkin in membranes of cerulein-treated cells.

CONCLUSIONS

DHA upregulates Parkin which inhibits vATPase-mediated zymogen activation, via GPR120 and GPR40, in cerulein-stimulated pancreatic acinar cells.

Updates to the n-3 polyunsaturated fatty acid biosynthesis pathway: DHA synthesis rates, tetracosahexaenoic acid and (minimal) retroconversion

N-3 polyunsaturated fatty acids (PUFA) and the numerous families of lipid mediators derived from them collectively regulate numerous biological processes. The mechanisms by which n-3 PUFA regulate biological processes begins with an understanding of the n-3 biosynthetic pathway that starts with alpha-linolenic acid (18:3n-3) and is commonly thought to end with the production of docosahexaenoic acid (DHA, 22:6n-3). However, our understanding of this pathway is not as complete as previously believed. In the current review we provide a background of the evidence supporting the pathway as currently understood and provide updates from recent studies challenging three central dogma of n-3 PUFA metabolism. By building on nearly three decades of research primarily in cell culture and oral dosing studies, recent evidence presented focuses on in vivo kinetic modelling and compound-specific isotope abundance studies in rodents and humans that have been instrumental in expanding our knowledge of the pathway. Specifically, we highlight three main updates to the n-3 PUFA biosynthesis pathway: (1) DHA synthesis rates cannot be as low as previously believed, (2) DHA is both a product and a precursor to tetracosahexaenoic acid (24:6n-3) and (3) increases in EPA in response to DHA supplementation are not the result of increased retroconversion.

Effects of the polyunsaturated fatty acids, EPA and DHA, on hematological malignancies: a systematic review

Omega-3 polyunsaturated fatty acids (PUFAs) have well established anti-cancer properties. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are among this biologically active family of macromolecules for which various anti-cancer effects have been explained. These PUFAs have a high safety profile and can induce apoptosis and inhibit growth of cancer cells both in vitro and in vivo, following a partially selective manner. They also increase the efficacy of chemotherapeutic agents by increasing the sensitivity of different cell lines to specific anti-neoplastic drugs. Various mechanisms have been proposed for the anti-cancer effects of these omega-3 PUFAs; however, the exact mechanisms still remain unknown. While numerous studies have investigated the effects of DHA and EPA on solid tumors and the responsible mechanisms, there is no consensus regarding the effects and mechanisms of action of these two FAs in hematological malignancies. Here, we performed a systematic review of the beneficial effects of EPA and DHA on hematological cell lines as well as the findings of related in vivo studies and clinical trials. We summarize the key underlying mechanisms and the therapeutic potential of these PUFAs in the treatment of hematological cancers. Differential expression of apoptosis-regulating genes and Glutathione peroxidase 4 (Gp-x4), varying abilities of different cancerous and healthy cells to metabolize EPA into its more active metabolites and to uptake PUFAS are among the major factors that determine the sensitivity of cells to DHA and EPA. Considering the abundance of data on the safety of these FAs and their proven anti-cancer effects in hematological cell lines and the lack of related human studies, further research is warranted to find ways of exploiting the anticancer effects of DHA and EPA in clinical settings both in isolation and in combination with other therapeutic regimens.

Are pupils' 'Programme for International Student Assessment (PISA)' scores associated with a nation's fish consumption?

AIMS

Omega-3 fatty acids are essential for neurodevelopment. Fish is a major source of these essential nutrients. We asked whether a nation's fish consumption is associated with its pupils' PISA scores as measures of school achievement, independent of economic status and breastfeeding. Method (Design and Setting): This was a regression analytic study based on published data.

RESULTS

Data on fish consumption and PISA scores were available for 64 countries. A significant regression model explained 72% of the variance in PISA scores. Breastfeeding does not enter the model. After controlling for technical and/or economic development, a nation's fish consumption remains a significant predictor, explaining an additional 4% of the variance.

DISCUSSION

This effect is likely due to the fact that fish, as the major source of omega-3 polyunsaturated fatty acids for a population, is important for the omega-3 supply to mothers and the early neurodevelopment of their children.

CONCLUSIONS

Fish consumption, as a proxy for a population's omega-3 supply, is an independent predictor of pupils' school achievement, in addition to a nation's economic development.

A Mini-Review on the Effect of Docosahexaenoic Acid (DHA) on Cerulein-Induced and Hypertriglyceridemic Acute Pancreatitis

Acute pancreatitis refers to the sudden inflammation of the pancreas. It is associated with premature activation and release of digestive enzymes into the pancreatic interstitium and systemic circulation, resulting in pancreatic tissue autodigestion and multiple organ dysfunction, as well as with increased cytokine production, ultimately leading to deleterious local and systemic effects. Although mechanisms involved in pathogenesis of acute pancreatitis have not been completely elucidated, oxidative stress is regarded as a major risk factor. In human acute pancreatitis, lipid peroxide levels in pancreatic tissues increase. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid (C22:6n-3), exerts anti-inflammatory and antioxidant effects on various cells. Previous studies have shown that DHA activates peroxisome proliferator-activated receptor-γ and induces catalase, which inhibits oxidative stress-mediated inflammatory signaling required for cytokine expression in experimental acute pancreatitis using cerulein. Cerulein, a cholecystokinin analog, induces intra-acinar activation of trypsinogen in the pancreas, which results in human acute pancreatitis-like symptoms. Therefore, DHA supplementation may be beneficial for preventing or inhibiting acute pancreatitis development. Since DHA reduces serum triglyceride levels, addition of DHA to lipid-lowering drugs like statins has been investigated to reduce hypertriglyceridemic acute pancreatitis. However, high DHA concentrations increase cytosolic Ca²⁺, which activates protein kinase C and may induce hyperlipidemic acute pancreatitis. In this review, effect of DHA on cerulein-induced and hypertriglyceridemic acute pancreatitis has been discussed. The relation of high concentration of DHA to hyperlipidemic acute pancreatitis has been included.

Docosahexaenoic Acid Inhibits Cerulein-Induced Acute Pancreatitis in Rats

Oxidative stress is an important regulator in the pathogenesis of acute pancreatitis (AP). Reactive oxygen species induce activation of inflammatory cascades, inflammatory cell recruitment, and tissue damage. NF-κB regulates inflammatory cytokine gene expression, which induces an acute, edematous form of pancreatitis. Protein kinase C δ (PKCδ) activates NF-κB as shown in a mouse model of cerulein-induced AP. Docosahexaenoic acid (DHA), an ω-3 fatty acid, exerts anti-inflammatory and antioxidant effects in various cells and tissues. This study investigated whether DHA inhibits cerulein-induced AP in rats by assessing pancreatic edema, myeloperoxidase activity, levels of lipid peroxide and IL-6, activation of NF-κB and PKCδ, and by histologic observation. AP was induced by intraperitoneal injection (i.p.) of cerulein (50 μg/kg) every hour for 7 h. DHA (13 mg/kg) was administered i.p. for three days before AP induction. Pretreatment with DHA reduced cerulein-induced activation of NF-κB, PKCδ, and IL-6 in pancreatic tissues of rats. DHA suppressed pancreatic edema and decreased the abundance of lipid peroxide, myeloperoxidase activity, and inflammatory cell infiltration into the pancreatic tissues of cerulein-stimulated rats. Therefore, DHA may help prevent the development of pancreatitis by suppressing the activation of NF-κB and PKCδ, expression of IL-6, and oxidative damage to the pancreas.

Docosahexaenoic acid inhibits IL-6 expression via PPARγ-mediated expression of catalase in cerulein-stimulated pancreatic acinar cells

Cerulein pancreatitis mirrors human acute pancreatitis. In pancreatic acinar cells exposed to cerulein, reactive oxygen species (ROS) mediate inflammatory signaling by Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 3, and cytokine induction. Docosahexaenoic acid (DHA) acts as an agonist of peroxisome proliferator activated receptor γ (PPARγ), which mediates the expression of some antioxidant enzymes. We hypothesized that DHA may induce PPARγ-target catalase expression and reduce ROS levels, leading to the inhibition of JAK2/STAT3 activation and IL-6 expression in cerulein-stimulated acinar cells. Pancreatic acinar AR42J cells were treated with DHA in the presence or absence of the PPARγ antagonist GW9662, or treated with the PPARγ agonist troglitazone, and then stimulated with cerulein. Expression of IL-6 and catalase, ROS levels, JAK2/STAT3 activation, and nuclear translocation of PPARγ were assessed. DHA suppressed the increase in ROS, JAK2/STAT3 activation, and IL-6 expression induced nuclear translocation of PPARγ and catalase expression in cerulein-stimulated AR42J cells. Troglitazone inhibited the cerulein-induced increase in ROS and IL-6 expression, but induced catalase expression similar to DHA in AR42J cells. GW9662 abolished the inhibitory effect of DHA on cerulein-induced increase in ROS and IL-6 expression in AR42J cells. DHA-induced expression of catalase was suppressed by GW9662 in cerulein-stimulated AR42J cells. Thus, DHA induces PPARγ activation and catalase expression, which inhibits ROS-mediated activation of JAK2/STAT3 and IL-6 expression in cerulein-stimulated pancreatic acinar cells.

Interaction of dietary fatty acids with tumour necrosis factor family cytokines during colon inflammation and cancer

Intestinal homeostasis is precisely regulated by a number of endogenous regulatory molecules but significantly influenced by dietary compounds. Malfunction of this system may result in chronic inflammation and cancer. Dietary essential n-3 polyunsaturated fatty acids (PUFAs) and short-chain fatty acid butyrate produced from fibre display anti-inflammatory and anticancer activities. Both compounds were shown to modulate the production and activities of TNF family cytokines. Cytokines from the TNF family (TNF- α, TRAIL, and FasL) have potent inflammatory activities and can also regulate apoptosis, which plays an important role in cancer development. The results of our own research showed enhancement of apoptosis in colon cancer cells by a combination of either docosahexaenoic acid (DHA) or butyrate with TNF family cytokines, especially by promotion of the mitochondrial apoptotic pathway and modulation of NF κ B activity. This review is focused mainly on the interaction of dietary PUFAs and butyrate with these cytokines during colon inflammation and cancer development. We summarised recent knowledge about the cellular and molecular mechanisms involved in such effects and outcomes for intestinal cell behaviour and pathologies. Finally, the possible application for the prevention and therapy of colon inflammation and cancer is also outlined.

Maternal dietary canola oil suppresses growth of mammary carcinogenesis in female rat offspring

As suggested by rodent studies and studies using human breast cancer cells, dietary canola oil is linked with lower breast cancer risk. Here, we investigated the effect of maternal (pregnancy plus lactation) dietary canola oil on the susceptibility of female Sprague-Dawley rat offspring to mammary carcinogenesis. Although the control diet had 10% soybean oil, the treatment diet was formulated to contain 10% canola oil as a fat source. N-nitroso-N-methylurea was injected to induce mammary cancer in offspring. The offspring of canola-fed dams showed significantly decreased tumor multiplicity (1.0 ± 0.3 vs. 1.9 ± 0.3, respectively; P = 0.04) and tumor volume (1232.5 ± 771.0 mm(3) vs. 6,302.5 ± 1,747.4 mm(3), respectively; P = 0.01), along with increased survival rate (87% vs. 47%, respectively; P = 0.01). In addition, the mRNA expression of development-related gamma-glutamyltransferase 1 was significantly higher in the lactating mammary tissues of the canola group dams and mammary tumor tissues of the offspring [2.5 ± 0.6 vs. 0.5 ± 0.2, respectively (P = 0.01) and 0.98 ± 0.03 vs. 0.56 ± 0.15, respectively (P = 0.05)]. These results suggest a potential anticancer effect of maternal dietary canola oil and may be useful in devising prenatal nutritional strategies to reduce breast cancer risk in humans.

Organochlorine pesticide residues: an extensive monitoring of Italian fishery and aquaculture

A sampling campaign from 21 sites in Italy was carried out to investigate the presence of organochlorine pesticide residues in different fish species. Samples came from marine fishery and either from sea- or freshwater aquaculture. Fish feed used in some fish farms were also analyzed. Pesticides studied belong to Persistent Organic Pollutants widely used in the past such as DDT, chlordane, heptachlor, and others. To ensure good quality results and proper data validation the main existing guidelines in the field were applied. The instrumental technique was a Dual column-Dual detector Gas Chromatography (GC-ECD and Ion Trap GC-MS) which allowed that complementary data on the same sample were acquired. Results for fishery showed a wide range of concentrations depending from the area and species examined. DDT, the major OC pesticide detected, varied from 0.02 to 130.03 ng g(-1) edible portion. As regards the products of aquaculture we observed slightly lower average levels of pollutants in a more narrow range of concentration: this is probably due to fish feed used as shown by some measures performed in the present study. Organochlorine pesticide residues were detected in all samples examined but they were generally well below the existing tolerance or action levels. Also the estimated daily intakes are well below than those recommended by WHO. This is a good indication about OCPs in the areas investigated but some further considerations on fish safety must be taken into account. An example on how fishes may act as bioindicators is reported.

Plasma phospholipid fatty acids and prostate cancer risk in the SELECT trial

BACKGROUND

Studies of dietary ω-3 fatty acid intake and prostate cancer risk are inconsistent; however, recent large prospective studies have found increased risk of prostate cancer among men with high blood concentrations of long-chain ω-3 polyunsaturated fatty acids ([LCω-3PUFA] 20:5ω3; 22:5ω3; 22:6ω3]. This case-cohort study examines associations between plasma phospholipid fatty acids and prostate cancer risk among participants in the Selenium and Vitamin E Cancer Prevention Trial.

METHODS

Case subjects were 834 men diagnosed with prostate cancer, of which 156 had high-grade cancer. The subcohort consisted of 1393 men selected randomly at baseline and from within strata frequency matched to case subjects on age and race. Proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) for associations between fatty acids and prostate cancer risk overall and by grade. All statistical tests were two-sided.

RESULTS

Compared with men in the lowest quartiles of LCω-3PUFA, men in the highest quartile had increased risks for low-grade (HR = 1.44, 95% CI = 1.08 to 1.93), high-grade (HR = 1.71, 95% CI = 1.00 to 2.94), and total prostate cancer (HR = 1.43, 95% CI = 1.09 to 1.88). Associations were similar for individual long-chain ω-3 fatty acids. Higher linoleic acid (ω-6) was associated with reduced risks of low-grade (HR = 0.75, 95% CI = 0.56 to 0.99) and total prostate cancer (HR = 0.77, 95% CI = 0.59 to 1.01); however, there was no dose response.

CONCLUSIONS

This study confirms previous reports of increased prostate cancer risk among men with high blood concentrations of LCω-3PUFA. The consistency of these findings suggests that these fatty acids are involved in prostate tumorigenesis. Recommendations to increase LCω-3PUFA intake should consider its potential risks.

Dietary ω-3 deficiency and IOP insult are additive risk factors for ganglion cell dysfunction

AIM

Dietary deficiencies in ω-3 polyunsaturated fatty acids are known to effect retinal function including retinal ganglion cell (RGC) activity, which may have implications for glaucoma. In this study we consider retinal function after dietary manipulation and intraocular pressure (IOP) stress designed to compromise RGCs.

METHODS

Sprague-Dawley dams were fed either ω-3 sufficient (ω-3, n=15) or deficient (ω-3, n=16) diets 5 weeks before conception with pups subsequently weaned onto their mothers diets. At 20 weeks of age, acute IOP elevation was induced repeatedly through anterior chamber cannulation to 70 mm Hg for 1 hour on 3 separate occasions separated by 1 week. Electroretinograms were recorded 1 week after each IOP elevation to assay the photoreceptors (PIII), ON-bipolar cells (PII), and ganglion/amacrine cells (STR).

RESULTS

Repeat IOP insult results in a specific RGC dysfunction (pSTR -14.5%, P<0.035) as does ω-3 deficiency (-26.4%, P<0.01). However, the combination of both causes an even larger RGC functional loss (-40.1%, P<0.001) than does either diet or IOP insult in isolation (P<0.001).

CONCLUSIONS

Both ω-3 deficiency and repeat acute IOP insult cause RGC dysfunction and the combination of these factors results in a cumulative effect. Our data indicate that sufficient dietary ω-3 improves RGC function making it less susceptible to IOP insult.

Docosahexaenoic fatty acid (DHA) in the regulation of colon cell growth and cell death: a review

BACKGROUND

Experimental, epidemiological and clinical data substantiate the beneficial role of n-3 polyunsaturated fatty acids (PUFAs) in preventing inflammation and cancer of the colon. This review covers the unsaturated docosahexaenoic fatty acid (DHA), describes some of its important cellular and molecular mechanisms, its interaction with another dietary lipid, butyrate and with endogenous apoptotic regulators of the tumour necrosis factor (TNF) family. We also discuss the clinical impact of this knowledge and the use of these lipids in colon cancer prevention and treatment.

RESULTS

From the literature, DHA has been shown to suppress the growth, induce apoptosis in colon cancer cells in vitro and decrease the incidence and growth of experimental tumours in vivo. Based on these data and our own experimental results, we describe and discuss the possible mechanisms of DHA anticancer effects at various levels of cell organization. We show that DHA can sensitize colon cancer cells to other chemotherapeutic/chemopreventive agents and affect the action of physiological apoptotic regulators of the TNF family.

CONCLUSION

Use of n-3 PUFAs could be a relatively non-toxic form of supportive therapy for improving colon cancer treatment and slowing down or preventing its recurrence. However, it is necessary to use them with caution, based on solid scientific evidence of their mechanisms of action from the molecular to the cellular and organism levels.

Flaxseed oil as a neuroprotective agent on lead acetate-induced monoamineric alterations and neurotoxicity in rats

Lead remains a considerable occupational and public health problem, which is known to cause a number of adverse effects in both man and animals. Here, the neuroprotective effect of flaxseed oil (1,000 mg/kg) on lead acetate (20 mg/kg) induced alternation in monoamines and brain oxidative stress was examined in rats. The levels of lead, dopamine (DA), norepinephrine (NE), serotonin (5-HT), lipid peroxidation, nitrite/nitrate (NO), and glutathione (GSH) were determined; also, the activity of acetylcholinesterase (AChE) and Na(+)-K(+)-ATPase were estimated on different brain regions of adult male albino rats. The level of lead was markedly elevated in different brain regions of rats. This leads to enhancement of lipid peroxidation and NO production in brain with concomitant reduction in AChE activity and GSH level. In addition, the levels of DA, NE, and 5-HT were decreased in the brain. These findings were associated with BAX over expression. Treatment of rats with flaxseed oil induced a marked improvement in most of the studied parameters as well as the immunohistochemistry features. These data indicated that dietary flaxseed oil provide protection against lead-induced oxidative stress and neurotoxic effects.

N-3 PUFAs have antiproliferative and apoptotic effects on human colorectal cancer stem-like cells in vitro

The n-3 polyunsaturated fatty acids have been shown to inhibit the induction and progression of many kinds of tumor and to increase the therapeutic effects of numerous chemotherapeutics, but their anticancer effect on cancer stem cells from colorectal cancer has not been described previously. In the present study, we cultivated spheres from the SW620 cell line in serum-free medium and evaluated the features of the spheres by immunofluorescence, cell cycle distribution, resistance to chemotherapeutics and soft agar clone formation, and the spheres were shown to be cancer stem-like cells through tumorigenicity in athymic nude mice. Reverse transcriptase polymerase chain reaction analysis of pluripotency genes, such as Sox-2, Oct-4 and Bmi-1, showed that the spheres were generated by dedifferentiation of SW620 cells. The study explored the use of n-3 polyunsaturated fatty acids (PUFAs) in spheres, which were treated with two n-3 PUFAs [docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA)]. Treatment of the spheres with DHA and EPA alone or in combination for 72 h led to apoptosis and the progressive loss of viability and DNA fragmentation and an increase in annexin V expression. DHA and EPA can enhance the chemotherapeutic sensitivity effect of 5-Fu and mitomycin C, especially DHA combined with EPA. Taken together, these results provide evidence that n-3 PUFAs exert a direct anticancer action that may contribute to their antiproliferative and proapoptotic effect on the cancer stem-like cells.

Analysis of fatty acids in 12 Mediterranean fish species: advantages and limitations of a new GC-FID/GC-MS based technique

When fatty acids in fish are analyzed, results in percentage form (profile analysis) are mostly reported. However, the much more useful results expressed as mg/100 g (absolute analysis) is the main information required. Absolute methods based on calibration curves are of good accuracy but with a high degree of complexity if applied to a great number of analytes. Procedures based on the sequence profile analysis-total FA determination-absolute analysis may be suitable for routine use, but suffer from a number of uncertainties that have never been really resolved. These uncertainties are mainly related to the profile analysis. In fact, most profile analyses reported in the literature disagree about the number and type of fatty acids monitored as well as about the total percentage to assign to their sum so leading to possible inaccuracies; in addition the instrumental response factor for all FAME (fatty acid methyl esters) is often considered as a constant, but this is not exactly true. In this work, a set of 24 fatty acids was selected and studied on 12 fish species in the Mediterranean area (variable in lipid content and month of sampling): in our results, and in these species, this set constitutes, on average, 90 ± 3 % of the total fatty acid content. Moreover the error derived from the assumption of a unique response factor was investigated. Two different detection techniques (GC-FID and GC-MS) together with two capillary columns (different in length and polarity) were used in order to acquire complementary data on the same sample. With the protocol here proposed absolute analyses on the 12 cited species are easily achievable by the total FA determination procedure. The accuracy of this approach is good in general, but in some cases (DHA for example) is lower than the accuracy of calibration-based methods. The differences were evaluated on a case by case basis.

The optimal male health diet and dietary supplement program

The primary cause of mortality in most developed countries is cardiovascular disease, which is the primary cause of death in the largest clinical studies of male health conditions. There are simplistic correlations between heart health and male-specific diseases. Clinicians need to motivate and provide a simplistic and realistic set of lifestyle, dietary supplement, and prescription drug recommendations to men to affect all-cause morbidity and mortality. This article provides recommendations to assist the clinician and patient to make practical changes that may be accomplished in a short period of time, and should provide tangible overall benefit for men's health.

Cod liver oil: a potential protective supplement for human glaucoma

Glaucoma is one of the leading causes of visual impairment and blindness. Improved knowledge of the pathogenesis of this disease has allowed the exploration of new therapeutic methods. In general, elevated intraocular pressure (IOP), oxidative stress, and vascular insufficiency are accepted as the major risk factors for the progression of glaucoma. Many natural compounds have been found beneficial for glaucoma. Nutritional therapies are now emerging as potentially effective in glaucomatous therapy. One nutritional supplement with potential therapeutic value is cod liver oil, a dietary supplement that contains vitamin A and omega-3 polyunsaturated fatty acids (PUFAs). Vitamin A is important for preserving normal vision and it is a well-known antioxidant that prevents the oxidative damage that contributes to the etiology and progression of glaucoma. Vitamin A is also a crucial factor for maintaining the integrity of conjunctival and corneal ocular surfaces, and preventing the impairment of ocular epithelium caused by topical antiglaucomatous drugs. Omega-3 fatty acids are beneficial for glaucoma patients as they decrease IOP, increase ocular blood flow, and improve optic neuroprotective function. In this article, we propose that cod liver oil, as a combination of vitamin A and omega-3 fatty acids, should be beneficial for the treatment of glaucoma. However, further studies are needed to explore the relationship between cod liver oil and glaucoma.

Docosahexaenoic acid metabolome in neural tumors: identification of cytotoxic intermediates

Docosahexaenoic acid (DHA) protects neural cells from stress-induced apoptosis. On the contrary, DHA exerts anticancer effects, and we have shown that DHA induces apoptosis in neuroblastoma, an embryonal tumor of the sympathetic nervous system. We now investigate the DHA metabolome in neuroblastoma using a targeted lipidomic approach in order to elucidate the mechanisms behind the DHA-induced cytotoxicity. LC-MS/MS analysis was used to identify DHA-derived lipid mediators in neuroblastoma cells. Presence of the 15-lipoxygenase enzyme was investigated using immunoblotting, and cytotoxic potency of DHA and DHA-derived compounds was compared using the MTT cell viability assay. Neuroblastoma cells metabolized DHA to 17-hydroxydocosahexaenoic acid (17-HDHA) via 17-hydroperoxydocosahexaenoic acid (17-HpDHA) through 15-lipoxygenase and autoxidation. In contrast to normal neural cells, neuroblastoma cells did not produce the anti-inflammatory and protective lipid mediators, resolvins and protectins. 17-HpDHA had significant cytotoxic potency, with an IC(50) of 3-6 microM at 72 h, compared to 12-15 microM for DHA. alpha-Tocopherol protected cells from 17-HpDHA-induced cytotoxicity. DHA inhibited secretion of prostaglandin-E(2) and augmented the cytotoxic potency of the cyclooxygenase-2-inhibitor celecoxib. The cytotoxic effect of DHA in neuroblastoma is mediated through production of hydroperoxy fatty acids that accumulate to toxic intracellular levels with restricted production of its products, resolvins and protectins.-Gleissman, H., Yang, R., Martinod, K., Lindskog, M., Serhan, C. N., Johnsen, J. I., Kogner, P. Docosahexaenoic acid metabolome in neural tumors: identification of cytotoxic intermediates.

Docosahexaenoic acid induces dose dependent cell death in an early undifferentiated subtype of acute myeloid leukemia cell line

Acute myeloid leukemia (AML) is the most frequently diagnosed adulthood leukemia, yet current therapies offer a cure rate of less than 30%. This may be due in part to the fact that the leukemia-initiating cells in AML reside within the rare and highly primitive CD34(+)CD38(-) hematopoietic stem/progenitor cell (HSC) population that are often resistant to chemotherapy. Docosahexanoic acid (DHA), a major component of fish oil, has previously been shown to inhibit the induction and progression of breast, prostate and colon cancer, and increase the therapeutic effects of numerous chemotherapeutics, often by enhancing apoptosis. In the present studies, we investigated DHA's effect on the primitive and undifferentiated AML cell line KG1a, to explore the potential of this fatty acid to serve as adjuvant therapy for AML. Treatment of KG1a cells with DHA for 96 hours did not lead to maturation or cell cycle modification when compared to an untreated KG1a control (n = 4). However, DHA treatment of KG1a cells resulted in a progressive loss of viability, DNA fragmentation, and an increase in Annexin V expression, demonstrating DHA-induced apoptosis (n = 4). Moreover, expression of the pro-apoptotic protein Bax was increased, with resultant skewing in the Bax/bcl-2 ratio, providing a mechanistic explanation for the observed DHA-induced increase in apoptosis. Since we also show that DHA does not have a detrimental effect on normal hematopoiesis our results suggest that DHA could potentially serve as an well-tolerated adjuvant in the treatment of AML patients.

Simulated impact of a fish based shift in the population n--3 fatty acids intake on exposure to dioxins and dioxin-like compounds

Due to the favourable health effects of LC n-3 PUFAs, marine products have been recognised as a food group of special importance in the human diet. However, seafood is susceptible to contamination by lipophilic organic pollutants. The objective of this study was to evaluate intake levels of PCDDs, PCDFs and dioxin-like PCBs, by a probabilistic Monte Carlo procedure, in relation to the recommendation on LC n-3 PUFAs given by Belgian Federal Health Council. Regarding the recommendation, two scenarios were developed differing in LC n-3 PUFAs intake: a 0.3 E% and a 0.46 E% scenario. Total exposure to dioxins and dioxin-like substances in the 0.3 E% LC n-3 PUFAs scenario ranges from 2.31 pg TEQ/kg bw/day at the 5th percentile, over 4.37 pg TEQ/kgbw/day at the 50th percentile to 8.41 pg TEQ/kgbw/day at the 95th percentile. In the 0.46 E% LC n-3 PUFAs scenario, 5, 50 and 95th percentile are exposed to 2.74, 5.52 and 9.98 pg TEQ/kgbw/day, respectively. Therefore, if the recommended LC n-3 PUFAs intake would be based on fish consumption as the only extra source, the majority of the study population would exceed the proposed health based guidance values for dioxins and dioxin-like substances.