Monounsaturated fats and immune function

Natural therapeutics and nutraceuticals for lung diseases: Traditional significance, phytochemistry, and pharmacology

BACKGROUND

Lung diseases including chronic obstructive pulmonary disease (COPD), infections like influenza, acute respiratory distress syndrome (ARDS), asthma and pneumonia lung cancer (LC) are common causes of sickness and death worldwide due to their remoteness, cold and harsh climatic conditions, and inaccessible health care facilities.

PURPOSE

Many drugs have already been proposed for the treatment of lung diseases. Few of them are in clinical trials and have the potential to cure infectious diseases. Plant extracts or herbal products have been extensively used as Traditional Chinese Medicine (TCM) and Indian Ayurveda. Moreover, it has been involved in the inhibition of certain genes/protiens effects to promote regulation of signaling pathways. Natural remedies have been scientifically proven with remarkable bioactivities and are considered a cheap and safe source for lung disease.

METHODS

This comprehensive review highlighted the literature about traditional plants and their metabolites with their applications for the treatment of lung diseases through experimental models in humans. Natural drugs information and mode of mechanism have been studied through the literature retrieved by Google Scholar, ScienceDirect, SciFinder, Scopus and Medline PubMed resources against lung diseases.

RESULTS

In vitro, in vivo and computational studies have been explained for natural metabolites derived from plants (like flavonoids, alkaloids, and terpenoids) against different types of lung diseases. Probiotics have also been biologically active therapeutics against cancer, anti-inflammation, antiplatelet, antiviral, and antioxidants associated with lung diseases.

CONCLUSION

The results of the mentioned natural metabolites repurposed for different lung diseases especially for SARS-CoV-2 should be evaluated more by advance computational applications, experimental models in the biological system, also need to be validated by clinical trials so that we may be able to retrieve potential drugs for most challenging lung diseases especially SARS-CoV-2.

Use of Natural Products in Asthma Treatment

Asthma, a disease classified as a chronic inflammatory disorder induced by airway inflammation, is triggered by a genetic predisposition or antigen sensitization. Drugs currently used as therapies present disadvantages such as high cost and side effects, which compromise the treatment compliance. Alternatively, traditional medicine has reported the use of natural products as alternative or complementary treatment. The aim of this review was to summarize the knowledge reported in the literature about the use of natural products for asthma treatment. The search strategy included scientific studies published between January 2006 and December 2017, using the keywords "asthma," "treatment," and "natural products." The inclusion criteria were as follows: (i) studies that aimed at elucidating the antiasthmatic activity of natural-based compounds or extracts using laboratory experiments (in vitro and/or in vivo); and (ii) studies that suggested the use of natural products in asthma treatment by elucidation of its chemical composition. Studies that (i) did not report experimental data and (ii) manuscripts in languages other than English were excluded. Based on the findings from the literature search, aspects related to asthma physiopathology, epidemiology, and conventional treatment were discussed. Then, several studies reporting the effectiveness of natural products in the asthma treatment were presented, highlighting plants as the main source. Moreover, natural products from animals and microorganisms were also discussed and their high potential in the antiasthmatic therapy was emphasized. This review highlighted the importance of natural products as an alternative and/or complementary treatment source for asthma treatment, since they present reduced side effects and comparable effectiveness as the drugs currently used on treatment protocols.

Bullfrog Oil Reduces the Carrageenan-induced Edema in Wistar Rats by in vitro Reduction of Inflammatory Mediators

Bullfrog oil (BFO) is a natural product from the adipose tissue of the amphibian Rana catesbeiana Shaw, a bio-product rich in polyunsaturated fatty acids, which claims anti-inflammatory activity. The objective of this work was to evaluate the cytotoxicity and the anti-inflammatory activity of BFO using in vivo and in vitro assays. Thus, the in vitro cytotoxicity was assessed by the MTT assay. Additionally, the in vivo anti-inflammatory activity was performed by the carrageenan-induced paw edema model in Wistar rats, followed by histological analysis. Moreover, the BFO effect on inflammatory pathways was investigated by in vitro evaluation of the nitric oxide (NO) synthesis, and type-6 interleukin (IL-6) and tumor-necrosis-factor (TNF) levels. In vivo experiments showed that BFO administered by intragastric route produced a significant anti-inflammatory effect, which was as substantial as indomethacin, the positive control. Histopathological analysis confirmed these results, showing the absence of the edema and minimal signs of inflammation in the paws of rats treated with BFO. The MTT results showed that BFO at all tested concentrations had no toxic effect against a macrophage cell line, not affecting the cell viability. In addition, after 48 hours of treatment, the BFO itself and its blend with Cetiol^®-V (1:1_v/v) at 200 µg.mL^-1 were able to reduce the NO synthesis, and the IL-6 and TNF levels up to 35 ± 2%, 40 ± 6%, and 12 ± 3%, respectively. Therefore, these results provide unprecedented scientific evidence of the anti-inflammatory effect of BFO, suggesting its potential as a new candidate for the development of pharmaceutical products with anti-inflammatory activity.

New Trends on Antineoplastic Therapy Research: Bullfrog (Rana catesbeiana Shaw) Oil Nanostructured Systems

Bullfrog oil is a natural product extracted from the Rana catesbeiana Shaw adipose tissue and used in folk medicine for the treatment of several diseases. The aim of this study was to evaluate the extraction process of bullfrog oil, to develop a suitable topical nanoemulsion and to evaluate its efficacy against melanoma cells. The oil samples were obtained by hot and organic solvent extraction processes and were characterized by titration techniques and gas chromatography mass spectrometry (GC-MS). The required hydrophile-lipophile balance and the pseudo-ternary phase diagram (PTPD) were assessed to determine the emulsification ability of the bullfrog oil. The anti-tumoral activity of the samples was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for normal fibroblast (3T3) and melanoma (B16F10) cell lines. Both extraction methods produced yielded around 60% and the oil was mainly composed of unsaturated compounds (around 60%). The bullfrog oil nanoemulsion obtained from PTPD presented a droplet size of about 390 nm and polydispersity = 0.05 and a zeta potential of about -25 mV. Both the bullfrog oil itself and its topical nanoemulsion did not show cytotoxicity in 3T3 linage. However, these systems showed growth inhibition in B16F10 cells. Finally, the bullfrog oil presented itself as a candidate for the development of pharmaceutical products free from cytotoxicity and effective for antineoplastic therapy.

Safety and efficacy of an olive oil-based triple-chamber bag for parenteral nutrition: a prospective, randomized, multi-center clinical trial in China

Background

Small studies suggest differences in efficacy and safety exist between olive oil-based (OLIVE) and soybean oil-based (SOYBEAN) parenteral nutrition regimens in hospitalized adult patients. This large, prospective, randomized (1:1), open-label, multi-center, noninferiority study compared the delivery, efficacy, and safety of OLIVE (N = 226) with SOYBEAN (N = 232) in Chinese adults (≥18 years) admitted to a surgical service for whom parenteral nutrition was required.

Methods

Treatments were administered for a minimum of 5 days up to 14 days (to achieve approximately 25 kcal/kg/day, 0.9 g/kg/day amino acids, 0.8 g/kg/day lipid). Impact of treatment on anabolic/catabolic and serum inflammatory, chemistry, and hematological markers, safety, and ease of use were assessed. The primary efficacy variable was serum prealbumin level at Day 5.

Results

OLIVE (n = 219) was not inferior to SOYBEAN (n = 224) based on the prealbumin least square geometric mean [LSGM] ratio [95 % CI] 1.12 [1.06, 1.19]; P = 0.002), improved the anabolic/catabolic status of patients enrolled in the study, and was well tolerated compared with SOYBEAN. Improved anabolic status was supported by significantly higher levels of prealbumin at Day 5, albumin at Day 5 and IGF-1 at Day 14 in the OLIVE group, while catabolism was similar between groups. C-reactive protein, intercellular adhesion molecule-1, procalcitonin, and oxidation were similar in each group, but infections were significantly lower with OLIVE (3.6 % versus 10.4 %; P < 0.01).

Conclusions

OLIVE provided effective nutrition, was well tolerated, was associated with fewer infections, and conferred greater ease-of-use than SOYBEAN.

Trial registration

NTC 01579097.

Management of hyperglycemia during enteral and parenteral nutrition therapy

Hyperglycemia is a frequent complication of enteral and parenteral nutrition in hospitalized patients. Extensive evidence from observational studies indicates that the development of hyperglycemia during parenteral and enteral nutrition is associated with an increased risk of death and infectious complications. There are no specific guidelines recommending glycemic targets and effective strategies for the management of hyperglycemia during specialized nutritional support. Managing hyperglycemia in these patients should include optimization of carbohydrate content and administration of intravenous or subcutaneous insulin therapy. The administration of continuous insulin infusion and insulin addition to nutrition bag are efficient approaches to control hyperglycemia during parenteral nutrition. Subcutaneous administration of long-acting insulin with scheduled or corrective doses of short-acting insulin is superior to the sliding scale insulin strategy in patients receiving enteral feedings. Randomized controlled studies are needed to evaluate safe and effective therapeutic strategies for the management of hyperglycemia in patients receiving nutritional support.

A double-blind, randomized clinical trial comparing soybean oil-based versus olive oil-based lipid emulsions in adult medical-surgical intensive care unit patients requiring parenteral nutrition

OBJECTIVE

Parenteral nutrition has been associated with metabolic and infectious complications in intensive care unit patients. The underlying mechanism for the high risk of complications is not known but may relate to the proinflammatory effects of soybean oil-based lipid emulsions, the only Food and Drug Administration-approved lipid formulation for clinical use.

DESIGN

Prospective, double-blind, randomized, controlled trial.

SETTING

Medical-surgical intensive care units from a major urban teaching hospital and a tertiary referral university hospital.

PATIENTS

Adult medical-surgical intensive care unit patients.

INTERVENTION

Parenteral nutrition containing soybean oil-based (Intralipid) or olive oil-based (ClinOleic) lipid emulsions.

MEASUREMENTS

Differences in hospital clinical outcomes (nosocomial infections and noninfectious complications), hospital length of stay, glycemic control, inflammatory and oxidative stress markers, and granulocyte and monocyte functions between study groups.

RESULTS

A total of 100 patients were randomized to either soybean oil-based parenteral nutrition or olive oil-based parenteral nutrition for up to 28 days. A total of 49 patients received soybean oil-based parenteral nutrition (age 51 ± 15 yrs, body mass index 27 ± 6 kg/m2, and Acute Physiology and Chronic Health Evaluation II score 15.5 ± 7 [±SD]), and a total of 51 patients received olive oil-based lipid emulsion in parenteral nutrition (age 46 ± 19 yrs, body mass index 27 ± 8 kg/m2, and Acute Physiology and Chronic Health Evaluation II score 15.1 ± 6 [±SD]) for a mean duration of 12.9 ± 8 days. The mean hospital blood glucose concentration during parenteral nutrition was 129 ± 14 mg/dL, without differences between groups. Patients treated with soybean oil-based and olive oil-based parenteral nutrition had a similar length of stay (47 ± 47 days and 41 ± 36 days, p = .49), mortality (16.3% and 9.8%, p = .38), nosocomial infections (43% vs. 57%, p = .16), and acute renal failure (26% vs. 18%, p = .34). In addition, there were no differences in inflammatory and oxidative stress markers or in granulocyte and monocyte functions between groups.

CONCLUSION

The administration of parenteral nutrition containing soybean oil-based and olive oil-based lipid emulsion resulted in similar rates of infectious and noninfectious complications and no differences in glycemic control, inflammatory and oxidative stress markers, and immune function in critically ill adults.

Medical nutrition therapy in hospitalized patients with diabetes

Medical nutrition therapy (MNT) plays an important role in management of hyperglycemia in hospitalized patients with diabetes mellitus. The goals of inpatient MNT are to optimize glycemic control, to provide adequate calories to meet metabolic demands, and to create a discharge plan for follow-up care. All patients with and without diabetes should undergo nutrition assessment on admission with subsequent implementation of physiologically sound caloric support. The use of a consistent carbohydrate diabetes meal-planning system has been shown to be effective in facilitating glycemic control in hospitalized patients with diabetes. This system is based on the total amount of carbohydrate offered rather than on specific calorie content at each meal, which facilitates matching the prandial insulin dose to the amount of carbohydrate consumed. In this article, we discuss general guidelines for the implementation of appropriate MNT in hospitalized patients with diabetes.

Substitution of standard soybean oil with olive oil-based lipid emulsion in parenteral nutrition: comparison of vascular, metabolic, and inflammatory effects

CONTEXT

Soybean oil-based lipid emulsions are the only Food and Drug Administration-approved lipid formulation for clinical use in parenteral nutrition (PN). Recently concerns with its use have been raised due to the proinflammatory effects that may lead to increased complications because they are rich in ω-6 polyunsaturated fatty acids.

METHODS

This was a prospective, randomized, controlled, crossover study comparing the vascular, metabolic, immune, and inflammatory effects of 24-h infusion of PN containing soybean oil-based lipid emulsion (Intralipid), olive oil-based (ClinOleic), lipid free, and normal saline in 12 healthy subjects.

RESULTS

Soybean oil-PN increased systolic blood pressure compared with olive oil-PN (P < 0.05). Soybean oil PN reduced brachial artery flow-mediated dilatation from baseline (-23% at 4 h and -25% at 24 h, both P < 0.01); in contrast, olive oil PN, lipid free PN, and saline did not change either systolic blood pressure or flow-mediated dilatation. Compared with saline, soybean oil PN, olive oil PN, and lipid free PN similarly increased glucose and insulin concentrations during infusion (P < 0.05). There were no significant changes in plasma free fatty acids, lipid profile, inflammatory and oxidative stress markers, immune function parameters, or sympathetic activity between soybean oil- and olive oil-based lipid emulsions.

CONCLUSION

The 24-h infusion of PN containing soybean oil-based lipid emulsion increased blood pressure and impaired endothelial function compared with PN containing olive oil-based lipid emulsion and lipid-free PN in healthy subjects. These vascular changes may have significant implications in worsening outcome in subjects receiving nutrition support. Randomized controlled trials with relevant clinical outcome measures are needed in patients receiving PN with olive oil-based and soybean oil-based lipid emulsions.

Molecular mechanisms by which saturated fatty acids modulate TNF-α expression in mouse macrophage lineage

Many macrophage functions are modulated by fatty acids (FAs), including cytokine release, such as tumor necrosis factor-α (TNF-α). TNF-α is of great interest due to its role in the inflammation process observed in several diseases such as rheumatoid arthritis, atherosclerosis, and obesity. However, the mechanisms by which FA effects occur have not been completely elucidated yet. In this study, we used a mouse monocyte lineage (J774 cells) to evaluate the effect of 50 and 100 μM of saturated (palmitic and stearic acids), monounsaturated (oleic acid) and polyunsaturated (linoleic acid) FAs on TNF-α production. Alterations in gene expression, poly(A) tail length and activation of transcription factors were evaluated. Oleic and linoleic acids, usually known as neutral or pro-inflammatory FA, inhibited LPS-induced TNF-α secretion by the cells. Saturated FAs were potent inducers of TNF-α expression and secretion under basal and inflammatory conditions (in the presence of LPS). Although the effect of the saturated FA was similar, the mechanism involved in each case seem to be distinct, as palmitic acid increased EGR-1 and CREB binding activity and stearic acid increased mRNA poly(A) tail. These results may contribute to the understanding of the molecular mechanisms by which saturated FAs modulate the inflammatory response and may lead to design of associations of dietary and pharmacological strategies to counteract the pathological effects of TNF-α.

Modulatory effect of fatty acids on fungicidal activity, respiratory burst and TNF-α and IL-6 production in J774 murine macrophages

The reported effects of different families of fatty acids (FA; SFA, MUFA, n-3 and n-6 PUFA) on human health and the importance of macrophage respiratory burst and cytokine release to immune defence led us to examine the influence of palmitic acid (PA), oleic acid (OA), linoleic acid, arachidonic acid, EPA and DHA on macrophage function. We determined fungicidal activity, reactive oxygen species (ROS) and cytokine production after the treatment of J774 cells with non-toxic concentrations of the FA. PA had a late and discrete stimulating effect on ROS production, which may be associated with the reduced fungicidal activity of the cells after treatment with this FA. OA presented a sustained stimulatory effect on ROS production and increased fungicidal activity of the cells, suggesting that enrichment of diets with OA may be beneficial for pathogen elimination. The effects of PUFA on ROS production were time- and dose-dependently regulated, with no evident differences between n-3 and n-6 PUFA. It was worth noting that most changes induced after stimulation of the cells with lipopolysaccharide were suppressed by the FA. The present results suggest that supplementation of the diet with specific FA, not classes of FA, might enable an improvement in host defence mechanisms or a reduction in adverse immunological reactions.

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.

The relationship between the fatty acid composition of immune cells and their function

The immune system, including its inflammatory components, is fundamental to host defence against pathogenic invaders. It is a complex system involving interactions amongst many different cell types dispersed throughout the body. Central to its actions are phagocytosis of bacteria, processing of antigens derived from intracellular and extracellular pathogens, activation of T cells with clonal expansion (proliferation) and production of cytokines that elicit effector cell functions such as antibody production and killing cell activity. Inappropriate immunologic activity, including inflammation, is a characteristic of many common human disorders. Eicosanoids produced from arachidonic acid have roles in inflammation and regulation of T and B lymphocyte functions. Eicosapentaenoic acid (EPA) also gives rise to eicosanoids and these may have differing properties from those of arachidonic acid-derived eicosanoids. EPA and docosahexaenoic acid (DHA) give rise to newly discovered resolvins which are anti-inflammatory and inflammation resolving. Human immune cells are typically rich in arachidonic acid, but arachidonic acid, EPA and DHA contents can be altered through oral administration of EPA and DHA. This results in a changed pattern of production of eicosanoids and probably also of resolvins, although the latter are not well examined in the human context. Changing the fatty acid composition of immune cells also affects phagocytosis, T cell signaling and antigen presentation capability. These effects appear to mediated at the membrane level suggesting important roles of fatty acids in membrane order, lipid raft structure and function, and membrane trafficking. Thus, the fatty acid composition of human immune cells influences their function and the cell membrane contents of arachidonic acid, EPA and DHA are important. Fatty acids influence immune cell function through a variety of complex mechanisms and these mechanisms are now beginning to be unraveled.

Prenatal fatty acid status and immune development: the pathways and the evidence

This review explores the effects of dietary long chain polyunsaturated fatty acids (LCPUFA) on various aspects of early immune development and their potential role in the development or the prevention of immune disease. Modern diets have become increasingly rich in n-6 LCPUFA and relatively n-3 LCPUFA deficient. These potentially "pro-inflammatory" dietary changes have clear implications for the immature and developing fetal immune system. It is now well known that immunological abnormalities precede the development of allergic disease and are frequently evident at birth or in the first months of life. This has lead to the hypothesis that potential effects of LCPUFA could be greatest in very early life before immune responses and clinical phenotype are established. Here we summarise the evidence that patterns of LCPUFA exposure in pregnancy can influence aspects of fetal immune in ways that are consistent with the immunological properties of these nutrients in adults. Specifically, human studies have shown that higher levels of n-3 LCPUFA are associated with reduction in neonatal oxidative stress, reduced production of inflammatory leukotienne B4 (LTB4) and altered T cell function. Inverse correlations between n-3 LCPUFA levels and neonatal T cell cytokine production, are consistent with adult studies showing reduction in T cell cytokine production with fish oil supplementation. At this stage the relevance of these effects in the prevention of disease is unclear. Although there have been no effects of postnatal fish oil supplementation (from 6 months of age) on allergy prevention, preliminary studies suggest possible merits in pregnancy and there are ongoing pregnancy intervention studies to address this more definitively.

High-dose fish oil and antioxidants in Crohn's disease and the response of bone turnover: a randomised controlled trial

Crohn's disease is associated with altered bone turnover that may be influenced by nutritional status, the systemic inflammatory response, cytokine production by circulating (peripheral blood) mononuclear cells (PBMC) and antioxidant micronutrient intake. High-dose fish oil is associated with reductions in disease relapse and inflammatory markers, and modulates PBMC function. The effect of fish oil plus antioxidants on bone turnover and PBMC function (the production of interferon-gamma and prostaglandin E2) in Crohn's disease was investigated in a randomised-controlled trial. Patients with currently or recently raised biochemical markers of inflammation (C-reactive protein > or = 6.9 mg/l or erythrocyte sedimentation rate > or =18 mm/h) received fish oil (providing 2.7 g/d EPA and DHA) and antioxidants (vitamins A, C and E, and Se) (n 31) or placebo (n 30) for 24 weeks. Bone turnover was assessed by measuring the concentrations of urinary deoxypyridinoline (bone resorption) and serum osteocalcin (bone formation). Fish oil plus antioxidants were associated with increases in EPA, DHA Se in plasma (all P < 0.01), and with a reduction in interferon-gamma production by mitogen-stimulated PBMC, which demonstrated a negative correlation with deoxypyridinoline/creatinine:osteocalcin ratio (r - 0.33, P = 0.009). There were no differences between the groups at 24 weeks in the response of deoxypyridinoline or osteocalcin or their ratio, or in nutritional status. Dietary supplementation in Crohn's disease with high intakes of EPA and DHA, as fish oil, plus antioxidants was associated with a modulated production of interferon-gamma by PBMC but not altered indices of bone turnover.

Improved fatty acid and leukotriene pattern with a novel lipid emulsion in surgical patients

OBJECTIVE

We assessed the effects of a novel lipid emulsion with reduced content of n-6 fatty acids (FA), increased share of MUFA and n-3 FA and supplemental vitamin E on fatty acid and leukotriene pattern in surgical patients.

METHODS

In a double-blind, randomized study 33 patients received isonitrogenous, isocaloric TPN over 5 postoperative days following major abdominal surgery. 19 patients received the new SMOFlipid 20% and 14 patients a standard soybean oil emulsion (Lipovenoes 20%, both Fresenius Kabi), each 1.5 g fat/kg body weight (BW)/d. Routine lipid biochemistry, plasma tocopherol, fatty acid pattern in plasma phospholipids, as well as leukotriene (LT) release in leukocytes were assessed. Additionally, fatty acid pattern in leukocyte and platelet phospholipids were analysed, but results are not presented.

RESULTS

On day 6, plasma alpha-tocopherol (34.2 +/- 10.3 vs. 17.6 +/- 2.9 micromol/L) and, in plasma PL, total n-3 FA were higher (11.1 +/- 1.9 vs. 4.9 +/- 0.9 mol%; p < 0.05) and total n-6 FA lower (23.8 +/- 2.2 vs. 31.8 +/- 1.7 mol%; P < 0.05); the ratio n-3/n-6 FA being elevated (0.5 +/- 0.1 vs. 0.2 +/- 0.0 p < 0.05) with SMOFlipid compared to the soybean oil emulsion. The shares of EPA (3.3+/-1.0 vs. 0.4+/-0.2 mol%; p<0.05) and DHA (6.9 +/- 1.8 vs. 3.7 +/- 0.8 mol%; p < 0.05) were highly increased but that of arachidonic acid (AA) was unchanged with SMOFlipid while the ratio EPA/AA was increased (0.7 +/- 0.2 vs. 0.1 +/- 0.0 p < 0.05). LTB(5) release was enhanced on day 6 (8.1 +/- 5.3 vs. 1.8 +/- 3.8 pmol/10(7) PMN, p < 0.05) and liberation of LTB(4) was lowered, yet not significantly with SMOFlipid (124.0 +/- 51.2 vs. 152.1 +/- 68.8 pmol/10(7) PMN). Length of hospital stay was significantly shorter with SMOFlipid (13.4 +/- 2.0 vs. 20.4 +/- 10.0 days, p < 0.05).

CONCLUSION

Treatment with the new emulsion SMOFlipid is well tolerated and modulates FA and leukotriene pattern suggesting favourable anti-inflammatory effects and further clinical benefits.

Maternal dietary ratio of linoleic acid to alpha-linolenic acid affects the passive immunity of hatching chicks

The objective of the current study was to examine the effect of dietary ratio of linoleic acid (LA) to alpha-linolenic acid (LNA) on the humoral immune response in laying hens and further on the passive immunity of their progeny. Thirty-two Single Comb White Leghorn laying hens, 24 wk of age, were randomly assigned to 1 of 4 diets that had LA-to-LNA ratios of 0.8, 5.4, 12.5, and 27.7, respectively, by changing the proportions of sunflower and linseed oils. After 5 wk on the experimental diets, hens were immunized intramuscularly with 1 mg of BSA, followed by 2 boosters 2 and 6 wk later. Serum and egg yolk were obtained weekly from 0 to 6 wk following the first injection of BSA. One week after the second booster, fertile eggs were collected and incubated. The sera of 11-d-old embryos and hatchlings were collected. All serum samples were stored at -20 degrees C before analysis. The results showed that dietary LA-to-LNA ratio had no effect on the total IgG and BSA-specific antibody IgG concentrations in the serum or egg yolk of laying hens. Hatchlings from hens fed the diet containing the LA-to-LNA ratio of 12.4 showed lower (P < 0.05) BSA-specific IgG titer in the serum than those from hens given the diet containing LA-to-LNA ratio of 0.8. A lower (P < 0.05) total IgG concentration was observed in hatchlings from hens fed the diet containing LA-to-LNA ratio of 12.4 compared with those from hens fed diets containing 0.8 and 5.4 of LA-to-LNA ratios. It is suggested that the dietary ratio of LA to LNA has no effect on laying hen humoral response but affects the passive immunity of hatching chicks.

Fish oil and antioxidants alter the composition and function of circulating mononuclear cells in Crohn disease

BACKGROUND

Crohn disease (CD) is associated with osteoporosis and other extraintestinal manifestations that might be mediated by cytokines from circulating (peripheral blood) mononuclear cells (PBMCs). Fish oil rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) reduces disease activity in patients with CD with raised laboratory markers of inflammation and in healthy subjects alters PBMC function.

OBJECTIVE

We investigated the effect of fish oil plus antioxidants on cytokine production by PBMCs from patients with CD with raised C-reactive protein concentrations (>/=6.9 mg/L) or erythrocyte sedimentation rates (>/=18 mm/h).

DESIGN

A randomized placebo-controlled trial of fish oil (2.7 g EPA and DHA/d; n = 31) or placebo (olive oil; n = 31) for 24 wk was conducted in patients with CD. The fish-oil group additionally received an antioxidant preparation (vitamins A, C, and E and selenium). Exclusion criteria included corticosteroid use. Fatty acid composition was measured by gas chromatography. Production of tumor necrosis factor alpha, interferon gamma (IFN-gamma), and prostaglandin E(2) (PGE(2)) was measured by enzyme-linked immunosorbent assays after stimulation with mitogen and endotoxin (lipopolysaccharide).

RESULTS

Fish-oil plus antioxidant dietary supplementation was associated with higher EPA and DHA incorporation into PBMCs (P < 0.001) and lower arachidonic acid (P = 0.006) and lower production of IFN-gamma by mitogen-stimulated PBMCs (P = 0.012) and of PGE(2) by lipopolysaccharide-stimulated PBMCs (P = 0.047).

CONCLUSION

Dietary supplementation with fish oil plus antioxidants is associated with modified PBMC composition and lower production of PGE(2) and IFN-gamma by circulating monocytes or macrophages. The response of extraintestinal manifestations of CD should be investigated in a randomized controlled trial.

Effect of bullfrog (Rana catesbeiana) oil administered by gavage on the fatty acid composition and oxidative stress of mouse liver

The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil), corresponding to 0.4% of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity) in mouse liver. The activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT), biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60%) in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05) compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25%) was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS) was increased from 2.3 +/- 0.2 to 12.3 +/- 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 +/- 32 to 1110 +/- 45 micromol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 +/- 0.12 to 342.84 +/- 0.13 and 9.38 +/- 0.60 to 20.06 +/- 0.27 U/g, respectively) and in serum (from 95.41 +/- 6.13 to 120.32 +/- 3.15 and 234.75 +/- 11.5 to 254.41 +/- 2.73 U/l, respectively), suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 +/- 0.29 to 315.98 +/- 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver.

Effect of a Dietary n-6 Polyunsaturated Fatty Acid Supplement on Distinct Immune Functions of Goats

The aim of this study was to investigate whether dietary n-6 polyunsaturated fatty acids (PUFA) alter immune functions as lymphocyte blastogenesis, expression of lymphocyte and monocyte markers, and cell adhesion molecules of the integrin family in goats. Dutch White castrated male goats received a diet either rich in olive oil (control group, n = 4) or rich in corn oil (test group, n = 4) over a period of 3 weeks. The animals in the test group had significantly higher linoleic acid (LA, 18:2n-6) levels in plasma on days 7, 14 and 21 of the diet than control animals. This was also true for washed erythrocyte membranes at day 21. A significant reduction in the percentage of alpha-4 integrin (CD49d) expressing lymphocytes was observed in goats fed LA rich corn oil at day 21. However, no changes were observed in either lymphocyte proliferative responses to ConA and PHA or the expression of other lymphocyte/monocyte markers. In conclusion, feeding corn oil rich in LA caused significant increases in the proportion of LA in the fatty acid composition of plasma and erythrocyte membranes and was accompanied by a significant decrease of the adhesion molecule alpha-4 integrin (CD49d) on lymphocytes but not on monocytes.

Fatty acids and lymphocyte functions

The immune system acts to protect the host against pathogenic invaders. However, components of the immune system can become dysregulated such that their activities are directed against host tissues, so causing damage. Lymphocytes are involved in both the beneficial and detrimental effects of the immune system. Both the level of fat and the types of fatty acid present in the diet can affect lymphocyte functions. The fatty acid composition of lymphocytes, and other immune cells, is altered according to the fatty acid composition of the diet and this alters the capacity of those cells to produce eicosanoids, such as prostaglandin E2, which are involved in immunoregulation. A high fat diet can impair lymphocyte function. Cell culture and animal feeding studies indicate that oleic, linoleic, conjugated linoleic, gamma-linolenic, dihomo-gamma-linolenic, arachidonic, alpha-linolenic, eicosapentaenoic and docosahexaenoic acids can all influence lymphocyte proliferation, the production of cytokines by lymphocytes, and natural killer cell activity. High intakes of some of these fatty acids are necessary to induce these effects. Among these fatty acids the long chain n-3 fatty acids, especially eicosapentaenoic acid, appear to be the most potent when included in the human diet. Although not all studies agree, it appears that fish oil, which contains eicosapentaenoic acid, down regulates the T-helper 1-type response which is associated with chronic inflammatory disease. There is evidence for beneficial effects of fish oil in such diseases; this evidence is strongest for rheumatoid arthritis. Since n-3 fatty acids also antagonise the production of inflammatory eicosanoid mediators from arachidonic acid, there is potential for benefit in asthma and related diseases. Recent evidence indicates that fish oil may be of benefit in some asthmatics but not others.