Adiposity associates with lower plasma resolvin E1 (Rve1): a population study.

BACKGROUND: Inadequate inflammation resolution may contribute to persistent low-grade inflammation that accompanies many chronic conditions. Resolution of inflammation is an active process driven by Specialized Pro-resolving Mediators (SPM) that derive from long chain n-3 and n-6 fatty acids. This study examined plasma SPM in relation to sex differences, lifestyle and a broad range cardiovascular disease (CVD) risk factors in 978, 27-year olds from the Australian Raine Study. METHODS: Plasma SPM pathway intermediates (18-HEPE, 17-HDHA and 14-HDHA), and SPM (E- and D-series resolvins, PD1, MaR1) and LTB4 were measured by liquid chromatography-tandem mass spectrometry (LCMSMS). Pearson correlations and multiple regression analyses assessed relationships between SPM and CVD risk factors. Unpaired t-tests or ANOVA assessed the effect of sex, smoking, unhealthy alcohol consumption and obesity on SPM. RESULTS: Women had higher 17-HDHA (p = 0.01) and lower RvE1 (p < 0.0001) and RvD1 (p = 0.05) levels compared with men. In univariate analysis, obesity associated with lower RvE1 (p = 0.002), whereas smoking (p < 0.001) and higher alcohol consumption (p < 0.001) associated with increased RvE1. In multiple regression analysis, plasma RvE1 was negatively associated with a range of measures of adiposity including BMI, waist circumference, waist-to-height ratio, abdominal subcutaneous fat volume, and skinfold thicknesses in both men and women. CONCLUSION: This population study suggests that a deficiency in plasma RvE1 may occur in response to increasing adiposity. This observation could be relevant to ongoing inflammation that associates with CVD and other chronic diseases.

A randomised controlled trial of succinylated gelatin (4%) fluid on urinary acute kidney injury biomarkers in cardiac surgical patients.

BACKGROUND: Fluid resuscitation is frequently required for cardiac surgical patients admitted to the intensive care unit. The ideal fluid of choice in regard to efficacy and safety remains uncertain. Compared with crystalloid fluid, colloid fluid may result in less positive fluid balance. However, some synthetic colloids are associated with increased risk of acute kidney injury (AKI). This study compared the effects of succinylated gelatin (4%) (GEL) with compound sodium lactate (CSL) on urinary AKI biomarkers in patients after cardiac surgery. METHODS: Cardiac surgical patients who required an intravenous fluid bolus of at least 500 mL postoperatively were randomly allocated to receive GEL or CSL as the resuscitation fluid of choice for the subsequent 24 h. Primary outcomes were serial urinary neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C concentrations measured at baseline, 1 h, 5 h and 24 h after enrolment, with higher concentrations indicating greater kidney injury. Secondary biomarker outcomes included urinary clusterin, α1-microglobulin and F2-isoprostanes concentrations. Differences in change of biomarker concentration between the two groups over time were compared with mixed-effects regression models. Statistical significance was set at P < 0.05. RESULTS: Forty cardiac surgical patients (n = 20 per group) with similar baseline characteristics were included. There was no significant difference in the median volume of fluid boluses administered over 24 h between the GEL (1250 mL, Q1-Q3 500-1750) and CSL group (1000 mL, Q1-Q3 500-1375) (P = 0.42). There was a significantly greater increase in urinary cystatin C (P < 0.001), clusterin (P < 0.001), α1-microglobulin (P < 0.001) and F2-isoprostanes (P = 0.020) concentrations over time in the GEL group, compared to the CSL group. Change in urinary NGAL concentration (P = 0.68) over time was not significantly different between the groups. The results were not modified by adjustment for either urinary osmolality or EuroSCORE II predicted risk of mortality. CONCLUSIONS: This preliminary randomised controlled trial showed that use of succinylated gelatin (4%) for fluid resuscitation after cardiac surgery was associated with increased biomarker concentrations of renal tubular injury and dysfunction, compared to crystalloid fluid. These results generate concern that use of intravenous gelatin fluid may contribute to clinically relevant postoperative AKI. Trial registration ANZCTR.org.au, ACTRN12617001461381. Registered on 16th October, 2017, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373619&isReview=true .

The effects of perioperative dexamethasone on eicosanoids and mediators of inflammation resolution: A sub-study of the PADDAG trial.

INTRODUCTION: Dexamethasone is an antiemetic that is frequently administered before or after the induction of anesthesia for prevention and treatment of perioperative nausea and vomiting. Dexamethasone has anti-inflammatory and immunosuppressive effects primarily via suppression of expression of inflammatory mediators. However, its effect on the eicosanoids and docosanoids that mediate the inflammatory response and inflammation resolution are unclear. We aimed to assess the effect of a single dose of intra-operative dexamethasone on peri­operative eicosanoids involved in inflammation including leukotriene B4 (LTB4) and 20-hydroxyeicosatetraenoic acid (20-HETE), and inflammation resolution (Specialised Proresolving Mediators (SPM)). PATIENTS AND METHODS: A subgroup of 80 patients from the randomised controlled PADDAG trial was enrolled into this substudy. They were allocated to receive 0, 4 or 8 mg dexamethasone administered intravenously at induction of anesthesia. Blood samples were collected before and 24 h after dexamethasone, for measurement of leukocytes, hs-CRP, LTB4, 20-HETE, the SPM pathway intermediates (14-HDHA, 18-HEPE and 17-HDHA) and SPMs (E-series resolvins, and d-series resolvins). RESULTS: Compared to the administration of placebo, neutrophil count was elevated (P<0.05) 24 h after administration of 4 and 8 mg dexamethasone. Dexamethasone (8 mg) resulted in increased levels of LTB4 (P = 0.012) and 20-HETE (P = 0.009) and reduced hs-CRP levels (P<0.001). Dexamethasone did not significantly affect plasma SPM pathway intermediates or RvE3. CONCLUSION: Antiemetic doses of dexamethasone given during surgery increased plasma LTB4 and 20-HETE at a time when hs-CRP was significantly reduced. Plasma SPM pathway intermediates and RvE3 were unaffected.

Increased inspired oxygen concentration does not adversely affect oxidative stress and the resolution of inflammation during reperfusion in patients undergoing knee replacement surgery.

The level of inspired oxygen during surgery may modify free radical release, and reperfusion injury. This controlled trial examined the effect of inspired oxygen on F2-isoprostanes (F2-IsoPs), isofurans (IsoFs), and specialized mediators of inflammation resolution (SPM) during knee replacement surgery. Patients received either 30% O2 (control n = 21), 50% O2 (n = 20), or 80% O2 (n = 19) O2, in a parallel design. Hemoglobin (Hb) was measured throughout the surgery and F2-IsoPs, IsoFs and SPM were analyzed by mass spectrometry. The effect of O2 on F2-IsoPs and IsoFs was examined during tourniquet inflation and after tourniquet release. SPM were measured at baseline and the end of surgery. There was a significant interaction between O2 and Hb concentrations with plasma IsoFs during tourniquet inflation. An increase in plasma IsoFs over time was attenuated in the 80% O2 group (p=.012) compared with the 30% O2 group after adjusting for Hb concentration. After tourniquet release, plasma F2-IsoPs were significantly lower in the 50% and 80% O2 groups (p=.009 and p=.001, respectively) compared with the 30% O2 group after adjustment for Hb concentration. The SPM RvD2 and RvE2 were increased with 50% and 80% O2 (RvD2, p=.014 and p=.002, respectively; RvE2, p=.032 with 50% O2) compared with the 30% O2 group, in analyses that corrected for Hb concentration. We have shown for the first time that higher O2 levels may be beneficial in reducing oxidative stress and increasing resolution of inflammation during surgery that involves reperfusion after application of a tourniquet.

Effects of antiemetic doses of dexamethasone on plasma mediators of inflammation resolution and pain after surgery in women.

BACKGROUND: Dexamethasone is commonly given as an antiemetic during surgical procedures. It has immunosuppressive effects and can affect key enzymes involved in the synthesis of specialised lipid mediators of inflammation resolution (SPM) that direct inflammation resolution and have anti-nociceptive actions. This study examined the effect of dexamethasone on plasma SPM, and the relationship between SPM and perceived pain in women undergoing surgery. METHODS: Plasma SPM were measured in samples obtained from two double-blind controlled interventions. The first, included 51 women mean age 53 ± 1.5 years, undergoing breast surgery allocated to either intravenous saline, or dexamethasone (4 mg or 8 mg) after induction of anaesthesia. The second study included 31 women of mean age 44 ± 0.5 years undergoing laparoscopic gynecological surgery that were allocated to either saline, or dexamethasone (4 mg). SPM (18-HEPE, 17-HDHA, RvE2, RvD1 17R-RvD1 and RvD2) were measured in plasma collected prior to induction of anaesthesia and at 24 h, and 6 weeks post-surgery. Pain was assessed using a verbal analogue scale at discharge from the post-anaesthesia recovery unit. The data from each study was combined to examine the effect of dexamethasone on plasma SPM. The relationship between pain score and SPM was examined using ordinal logistic regression. RESULTS: The SPM 18-HEPE, 17-HDHA, RvE2, RvD1 17R-RvD1 and RvD2 were detectable in all plasma samples. There was no significant difference in any SPM due to dexamethasone over the duration of the study. There was a fall in 17-HDHA between baseline and 24 h in both the dexamethasone and saline groups (P = 0.003) but no change in the downstream SPM (RvD1, 17R-RvD1 and RvD2) or 18-HEPE and RvE2. Pain score was negatively related to levels of RvE2 measured prior to induction of anaesthesia (rho = -0.2991, P = 0.006) and positively related to BMI (rho = 0.279, P = 0.011). In ordinal logistic regression the odds ratio for RvE2 was 0.931 (CI 0.880, 0.986; P = 0.014); after adjusting for the effect of BMI indicating that an increase in RvE2 of 1 pg/ml would result in a 6.9 % fall in pain score. Allocation to a dexamethasone group did not influence the pain score or the relationship between RvE2 and pain score. CONCLUSION: Dexamethasone administered as an anti-emetic does not affect plasma SPM levels. An elevated RvE2 level prior to surgery is predictive of a lower perceived pain score post-anaesthesia.

Evaluation of biomarkers of kidney injury following 4% succinylated gelatin and 6% hydroxyethyl starch 130/0.4 administration in a canine hemorrhagic shock model.

OBJECTIVE: To investigate the association between synthetic colloids and biomarkers of acute kidney injury (AKI) in dogs with hemorrhagic shock. DESIGN: Experimental interventional study. SETTING: University. ANIMALS: Twenty-four healthy ex-racing Greyhounds. INTERVENTIONS: Anesthetized Greyhounds subjected to hemorrhage for 60 min were resuscitated with 20 mL/kg of fresh whole blood (FWB), 6% hydroxyethyl starch (HES) 130/0.4, 4% succinylated gelatin (GELO), or 80 mL/kg of isotonic crystalloid (CRYST) over 20 min (n = 6 per treatment). Concentrations of biomarkers of AKI were measured at baseline, end of hemorrhage, and at 40 (T60), 100 (T120), and 160 (T180) min after fluid bolus. Biomarkers included neutrophil gelatinase-associated lipocalin in urine and serum (uNGAL; sNGAL), and urine cystatin C (uCYSC), kidney injury molecule-1 (uKIM), clusterin (uCLUST), osteopontin, gamma-glutamyl transferase, monocyte chemoattractant protein-1 (uMCP), interleukin-6, interleukin-8, protein (uPROT), hyaluronan, and F2 -isoprostanes. Renal histology was scored for tubular injury and microvesiculation. Biomarker fold-change from baseline was compared between groups using mixed effects models (Bonferroni-Holm corrected P<0.05). Frequencies of histology scores were compared by Fisher's exact test. MEASUREMENTS AND MAIN RESULTS: In dogs treated with GELO, uNGAL fold-change was markedly greater compared with all other groups at T60, T120, and T180 (all P<0.001), and uCYSC was greater at T60 compared with CRYST (P<0.001), and at T120 and T180 compared with all other groups (all P<0.001). Smaller, albeit significant, between-group differences in uKIM, uCLUST, uMCP, and urine protein concentration were observed across the FWB, GELO, and HES groups, compared with CRYST. The GELO group more frequently had marked tubular microvesiculation than the other groups (P = 0.015) although tubular injury scores were comparable. CONCLUSION: In dogs with hemorrhagic shock, GELO was associated with greater magnitude increases in urine biomarkers of AKI and more frequent marked tubular microvesiculation, compared with FWB, CRYST, and HES.

The effects of alcohol on plasma lipid mediators of inflammation resolution in patients with Type 2 diabetes mellitus.

BACKGROUND: Type 2 diabetes mellitus is characterized by peripheral insulin resistance and low-grade systemic inflammation. Inflammation resolution is recognised as an important process driven by specialised pro-resolving mediators of inflammation (SPMs) and has the potential to moderate chronic inflammation. Alcohol has the potential to affect synthesis of SPMs by altering key enzymes involved in SPM synthesis and may influence ongoing inflammation associated with Type 2 diabetes mellitus. AIMS: (i) To examine the effects of alcohol consumed as red wine on plasma SPM in men and women with Type 2 diabetes in a randomised controlled trial and (ii) compare baseline plasma SPM levels in the same patients with those of healthy volunteers. METHODS: Twenty-four patients with Type 2 diabetes mellitus were randomized to a three-period crossover study with men drinking red wine 300 ml/day (∼31 g alcohol/day) and women drinking red wine 230 ml/day (∼24 g alcohol/day), or equivalent volumes of dealcoholized red wine (DRW) or water, each for 4 weeks. The SPM 18-hydroxyeicosapentaenoic acid (18-HEPE), E-series resolvins (Rv) (RvE1-RvE3), 17-hydroxydocosahexaenoic acid (17-HDHA), and D-series resolvins (RvD1, 17R-RvD1, RvD2, RvD5), 14-hydroxydocosahexaenoic acid (14-HDHA) and Maresin 1 were measured at the end of each period. A baseline comparison of plasma SPM, hs CRP, lipids and glucose was made with healthy volunteers. RESULTS: Red wine did not differentially affect any of the SPM measured when compared with DRW or water. Baseline levels of the hs-CRP and the SPM 18-HEPE, 17-HDHA, RvD1 and 17R-RvD1 in patients with Type 2 diabetes mellitus were all significantly elevated compared with healthy controls and remained so after adjusting for age and gender. CONCLUSION: Moderate alcohol consumption as red wine does not alter plasma SPM in patients with Type 2 diabetes mellitus. The elevation of SPM levels compared with healthy volunteers may be a homeostatic response to counter ongoing inflammation.

Hyperbaric oxygen therapy is not associated with oxidative stress assessed using plasma F2-isoprostanes and isofurans.

BACKGROUND AND AIMS: Hyperbaric oxygen (HBO) therapy is increasingly used in medical practice as a means of enhancing the formation of collagen matrix and angiogenesis, thus promoting healing in wounds and necrotic tissue. However, there are concerns that oxygen can also associate with increased production of oxygen free radicals and oxidative stress. F2-Isoprostanes (F2-IsoPs) formed by non-enzymatic oxidation of arachidonic acid (AA) are reliable measures for assessing oxidative stress in vivo. In addition, under conditions of high oxygen tension isofurans (IsoFs) are preferentially formed from AA and are considered to better reflect oxidative stress in the setting of high oxygen tension. This study aimed to measure plasma IsoFs and F2-IsoP in patients receiving HBO therapy to treat osteonecrosis secondary to radiation therapy. Our hypothesis was that IsoFs would continue to rise with increasing oxygen pressures in contrast to F2-IsoPs whose synthesis would be reduced. METHODS: Twelve patients receiving hyperbaric therapy to treat osteonecrosis secondary to radiation therapy were studied during hyperbaric treatment. Blood samples were collected prior to, during and after cessation of HBO therapy that lasted for 119min. Seven serial blood samples were collected for measurement of plasma F2-IsoPs and IsoFs, blood gases and haemoglobin. RESULTS: Oxygen saturation and venous oxygen partial pressure (PvO2) rose significantly during hyperbaric therapy. However, there were no significant changes in plasma IsoFs or F2-IsoPs during the hyperbaric therapy session. CONCLUSION: In this study of patients with osteonecrosis, HBO therapy at a maximum pressure of 2.4atm with up to 100% oxygen did not worsen oxidative stress assessed using plasma F2- IsoFs and IsoPs.

A Randomized Trial of Effects of Alcohol on Cytochrome P450 Eicosanoids, Mediators of Inflammation Resolution, and Blood Pressure in Men.

BACKGROUND: Cardiovascular effects of alcohol consumption may be influenced by both pro- and anti-inflammatory mechanisms. We previously showed that chronic alcohol consumption increased blood pressure (BP), oxidative stress, and 20-hydroxyeicosatetraenoic acid (20-HETE), a vasoconstrictor and pro-inflammatory eicosanoid synthesized by cytochrome P450 (CYP450) enzymes from arachidonic acid. This study in men examined the effect of consuming red wine (RW) on BP in relation to changes in 20-HETE, oxidative stress (F2 -isoprostanes), markers of inflammation, anti-inflammatory CYP450 epoxyeicosatrienoic acids (EETs), and specialized pro-resolving mediators of inflammation (SPMs) derived from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). METHODS: Normotensive men (n = 22) were randomly allocated to drink RW (375 ml/d) or the equivalent volume of dealcoholized red wine (DRW) or water for 4 weeks in a 12-week, 3-period crossover trial. BP, heart rate, 20-HETE, F2 -isoprostanes, and SPM were measured at baseline, 4, 8, and 12 weeks. RESULTS: Drinking RW increased BP (p < 0.05), plasma and urinary 20-HETE (p < 0.05), plasma F2 -isoprostanes (p < 0.0001), and the SPMs 18-hydroxyeicosapentaenoic acid (18-HEPE) from EPA, and resolvin D1 (RvD1) and 17R-resolvin D1 (17R-RvD1) from DHA (all p < 0.05) compared with DRW and water. EETs and high-sensitivity C-reactive protein were unaffected by RW. Plasma 18-HEPE was positively related to urinary 20-HETE (p < 0.008) only after RW. CONCLUSIONS: This study has shown that men consuming moderate-to-high alcohol as RW for 4 weeks had increased BP, 20-HETE, and oxidative stress, as well as specific SPM that resolve inflammation. These paradoxical findings require further studies to determine whether alcohol stimulates different CYP450 enzymes and whether the findings can be replicated in females.

Controlled moderate hypovolaemia in healthy volunteers is not associated with the development of oxidative stress assessed by plasma F2-isoprostanes and isofurans.

Hypovolaemia can be associated with substantial morbidity, particularly when it occurs in the setting of trauma and in patients with comorbid diseases. Hypovolaemia and inflammation such as occur in the setting of trauma and surgery, are associated with systemic oxidative stress and free-radical injury. Free-radical injury that results from hypovolaemia-induced organ reperfusion may further augment inflammatory processes. It is unknown exactly what proportion of free-radical injury is associated with isolated hypovolaemia as opposed to the contribution from inflammation from surgery or trauma. In the first human study of its kind, we exposed 8 adult male volunteers to venesection-induced hypovolaemia in progressive aliquots of 5% of total blood volume until 20% had been removed. This blood was subsequently reinfused. Plasma F2-isoprostanes and isofurans, markers of in vivo lipid oxidation, were measured by gas chromatography-mass spectrometry at each 5% aliquot venesected and at each 5% reinfused. Between baseline and maximal blood loss there was a minor fall in haemoglobin concentration from 143.9g/l to 138.8g/l (p=0.004, 95% CI 2.2, 8.0g/L). No significant change from baseline occurred in the concentrations of either plasma F2-isoprostanes or isofurans during venesection (p=0.116 and p=0.152, respectively) or blood reinfusion (p=0.553 and p=0.736, respectively). We can conclude that in healthy adult volunteers, isolated hypovolaemia to 20% total blood volume loss is not associated with detectable systemic oxidative stress. The free-radical injury identified in surgical and trauma patients may represent the effects of tissue damage and inflammation, with an uncertain contribution from tissue ischemia as may occur with hypovolaemia.

Echium oil is better than rapeseed oil in improving the response of barramundi to a disease challenge.

Pathogen infection stimulates the fatty acid (FA) metabolism and the production of pro-inflammatory derivatives of FA. Barramundi, Lates calcarifer, was fed on a diet rich in preformed long-chain (⩾C20) polyunsaturated fatty acids (LC-PUFA) from fish oil (FO), to compare with diets containing high levels of C18 precursors for LC-PUFA - stearidonic (SDA) and γ-linolenic acid (GLA) - from Echium plantagineum (EO), or rapeseed oil (RO) rich in α-linolenic acid (ALA), but a poor source of LC-PUFA and their precursors. After 6weeks, when growth rates were similar amongst the dietary treatments, a sub-lethal dose of Streptococcus iniae was administered to half of the fish, while the other half were maintained unchallenged and were pair-fed with the infected fish. Under a disease challenge situation, the tissue FA depots depleted at 3days post-infection (DPI) and were then restored to their previous concentrations at 7DPI. During the infection period, EO fish had a higher content of n3 and n6 PUFA in their tissues, higher n3:n6 PUFA ratio and reduced levels of the eicosanoids, TXB2 and 6-keto-PGF1α, in their plasma compared with RO fish. Fish fed on FO and EO had a longer lasting and enduring response in their FA and eicosanoid concentrations, following a week of bacterial infection, compared with those fed on RO. EO, containing SDA and GLA and with a comparatively higher n3:n6 PUFA ratio, proved more effective than RO in compensating for immunity stress.

Hemoglobin attenuates the effects of inspired oxygen on plasma isofurans in humans during upper-limb surgery.

Reperfusion injury is characterized by significant oxidative stress. F(2)-isoprostanes (F(2)-IsoP's) and isofurans (IsoF's), the latter preferentially produced during increased oxygen tension, are recognized markers of in vivo oxidative stress. We aimed to determine whether increasing oxygen tension during reperfusion modified levels of plasma total IsoF's and F(2)-IsoP's. Forty-five patients undergoing upper-limb surgery were randomized to receive inspired oxygen concentrations of 30, 50, or 80% during the last 15 min of surgery. Venous blood samples were taken before the change in inspired oxygen, after 10 min (before reperfusion), and after 15 min (5 min after reperfusion). IsoF's and F(2)-IsoP's were measured by gas chromatography-mass spectrometry. Venous oxygen tension and hemoglobin concentrations were also measured. Plasma IsoF and F(2)-IsoP levels in the 50 and 80% O(2) groups were not significantly different from those of the 30% O(2) group. In secondary analyses, using data combining all groups, levels of IsoF's, but not F(2)-IsoP's, associated with higher venous oxygen tension (P=0.038). Hemoglobin negatively modified the influence of oxygen tension on levels of IsoF's (P=0.014). This study has shown, for the first time, that plasma IsoF levels associate with higher oxygen tension in a human model of reperfusion, and this effect is significantly attenuated by hemoglobin.

Effects of spinal or general anesthesia on F2-isoprostanes and isofurans during ischemia/reperfusion of the leg in patients undergoing knee replacement surgery.

General and spinal anesthesia are used extensively in orthopedic surgery. However, these methods of anesthesia may result in different amounts of oxygen being delivered to the patient. Ischemia/reperfusion injury after release of the tourniquet initiates free radical-mediated oxidative stress. F2-isoprostanes are reliable markers of in vivo lipid peroxidation. However, under conditions of high oxygen tension, isofurans are formed. We aimed to compare plasma isofurans and F2-isoprostanes in spinal versus general anesthesia in patients undergoing knee-replacement surgery in a randomized, blinded study. Thirty-nine patients were randomized to spinal (SA; n = 19) or general anesthesia (GA; n = 20). Blood was collected before anesthesia, and a tourniquet was then applied to the limb during surgery. After release of the tourniquet, blood samples were collected at 30 min, 2 h, and 24 h for measurement of plasma F2-isoprostanes and isofurans by gas chromatography-mass spectrometry. The two groups were comparable in age and body mass index. Plasma F2-isoprostanes were significantly lower in the GA patients compared with the SA patients (p = 0.045). In contrast, the GA patients had significantly elevated plasma isofurans (p = 0.032). Increased isofurans during GA compared with SA are likely to reflect increased oxidative stress due to elevated oxygen concentrations during GA. Further studies are required to assess the implications of these findings on perioperative outcomes.

The effects of a lupin-enriched diet on oxidative stress and factors influencing vascular function in overweight subjects.

A diet enriched in lupin kernel flour can lower blood pressure, but mechanisms responsible are unclear. Lupin is a source of polyphenols, protein, and L-arginine, factors that may influence blood pressure via effects on oxidative stress and vascular function. Therefore, we aimed to determine the effects of a lupin-enriched diet on oxidative stress and factors influencing vascular function as potential mechanisms for demonstrated benefits on blood pressure. Overweight men and women (n = 88) were recruited to a 16-week parallel-design study. Participants were randomly assigned to replace 15%-20% of their usual daily energy intake with white bread (control) or lupin kernel flour-enriched bread (lupin). All measurements were taken at baseline and 16 weeks. At baseline, plasma F2-isoprostanes and 20-hydroxyeicosatetraenoic acid (20-HETE) were positively associated with blood pressure, and plasma nitrite was negatively associated with blood pressure (p < 0.05). For lupin relative to control, the estimated differences in plasma F2-isoprostanes (45 pmol/L; 95%CI: -68, 158), urinary F2-isoprostanes (17 pmol/mmol creatinine; 95%CI: -43, 76), plasma 20-HETE (75 pmol/L; 95%CI: -91, 241), and plasma nitrite (-0.3 µmol/L; 95%CI: -1.1, 0.4) were not significant. Although regular consumption of lupin-enriched bread can lower blood pressure, these results do not support for the hypothesis that this is via effects on oxidative stress or vascular function.

Measurement of urinary F(2)-isoprostanes by gas chromatography-mass spectrometry is confounded by interfering substances.

Analysis of F(2)-isoprostanes in urine using gas chromatography-mass spectrometry is confounded by the presence of endogenous compounds interfering with the internal standard, 15-F(2t)-IsoP-d(4) (m/z 573). Previous efforts to resolve the 15-F(2t)-IsoP-d(4) from co-eluting peaks with different solid phase extractions were unsuccessful. This study has now used a highly-deuterated, d(9)-analogue of the derivatization agent N,O-Bis(trimethyl-d(9)-silyl) trifluoroacetamide (BSTFA-d(9)) yielding trimethylsilyl ethers, but this was not successful in resolving the 15-F(2t)-IsoP-d(4) from co-eluting peaks. It was hypothesized that interfering peaks at m/z 573 could be the tetrahydro analogue of 15-F(2t)-IsoP. However, using an authentic standard showed the interfering peaks are not due to this metabolite. In subsequent experiments good resolution was shown of the 15-F(2t)-IsoP peak using 8-F(2t)-IsoP-d(4) (m/z 573) as the internal standard. These data show that care must be taken when using GC-MS for quantitation of F(2)-IsoPs to prevent interfering substances affecting the results.

Flaxseed oil supplementation increases plasma F1-phytoprostanes in healthy men.

Supplementation with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has been reported to reduce lipid peroxidation products formed from arachidonic acid (F(2)-isoprostanes) in healthy humans, as well as in those under oxidative stress. alpha-Linolenic acid (ALA) is a precursor to EPA and DHA; however, its conversion in humans is thought to be inefficient. ALA can also undergo free radical oxidation, forming compounds known as F(1)-phytoprostanes, which are found in all plants and are in high concentrations in plant pollens. In this study, we examined the effect of ALA supplementation on plasma and urine F(1)-phytoprostane and F(2)-isoprostane concentrations in men. Thirty-six nonsmoking men, aged 20-65 y, were recruited from the general population and randomly allocated to consume 9 g/d of either flaxseed oil (62% ALA, 5.4 g/d) or olive oil (placebo) for 4 wk in a parallel design. At baseline and after 4 wk of supplementation, blood samples and a 24-h urine sample were collected for measurement of plasma and urinary F(1)-phytoprostanes and F(2)-isoprostanes and plasma fatty acids. Compared with the olive oil group, plasma phospholipid ALA was greater (P < 0.0001), as were F(1)-phytoprostanes in plasma (P = 0.049) and urine (P = 0.06) in the flaxseed oil group after 4 wk supplementation. Flaxseed oil did not affect plasma or urinary F(2)-isoprostanes. The greater plasma F(1)-phytoprostane concentration in the flaxseed oil group most likely resulted from the increased plasma concentration of the ALA substrate and/or the F(1)-phytoprostane content of the flaxseed oil. Future studies are needed to determine the physiological importance of increased plasma and urine F(1)-phytoprostanes and their relevance to heart disease prevention.

Maternal fish oil supplementation in pregnancy modifies neonatal leukotriene production by cord-blood-derived neutrophils.

Fish oil supplementation has been shown to reduce neutrophil production of inflammatory LTB4 (leukotriene B4) in adults. The present study is the first to examine the effects on neonatal neutrophil function following supplementation in pregnancy. Pregnant women with allergic disease (n=98) were randomized to receive either fish oil [3.7 g of n-3 long-chain PUFAs (polyunsaturated fatty acids)/day] or a placebo supplement for the final 20 weeks of pregnancy. Leukotriene production by neonatal neutrophils was measured after stimulation with the calcium ionophore A23187. This was examined in relation to supplementation, cell membrane fatty acid levels and mononuclear cytokine production. Neutrophil LTB4 production was significantly reduced in neonates whose mothers had received fish oil in pregnancy. This was most evident for isomer 2 of LTB4 (P=0.031), although this was also observed for total LTB4 (P=0.051) and isomer 1 (P=0.088). There was also a trend for lower production of other PUFA metabolites, namely 5-HETE (5-hydroxyeicosatetraenoic acid; P=0.054) in the fish oil group. Accordingly, LTB4 levels were inversely related to membrane n-3 PUFA levels. Less inflammatory products (LTB5) were only produced at very low levels, although there was a trend for higher levels of this metabolite in the fish oil group. Consistent with this, LTB5 levels were positively correlated with n-3 PUFA membrane levels, particularly EPA (eicosapentanoic acid) and negatively correlated with n-6 PUFAs. Neonates with lower neutrophil LTB4 production also had lower production of pro-inflammatory IL (interleukin)-6 responses (r=0.35, P=0.005) and regulatory IL-10 responses (r=0.37, P=0.003) by LPS (lipopolysaccharide)-stimulated neonatal mononuclear cells. In conclusion, maternal dietary changes can modify neonatal neutrophil function. This has implications for the early immune programming, which can be influenced by the inflammatory milieu of local tissues during initial antigen encounter. It also provides evidence of another pathway through which long-chain PUFAs status can influence early immune development.

Association of maternal smoking with increased infant oxidative stress at 3 months of age.

BACKGROUND: Cigarette smoke is a major source of free radicals and oxidative stress. With a significant proportion of women still smoking during pregnancy, this common and avoidable exposure has the potential to influence infant oxidative status, which is implicated in the increased propensity for airway inflammation and asthma. The aim of this study was to examine the effects of maternal smoking on markers of infant oxidative stress. METHODS: The level of oxidative stress (using urinary F2-isoprostanes as a marker of lipid peroxidation) was compared in infants of smokers (n = 33) and non-smokers (n = 54) at 3 months of age. These groups were balanced for maternal atopy and socioeconomic status. Infant urinary cotinine levels were also measured as an indicator of early postnatal cigarette smoke exposure. RESULTS: Maternal smoking was associated with significantly higher infant cotinine levels, despite the fact that most smoking mothers (83.8%) claimed not to smoke near their baby. Maternal smoking was associated with significantly higher markers of oxidative stress (F2-isoprostane) at 3 months of age. There was also a positive correlation between urinary F2-isoprostanes and infant urinary cotinine levels. CONCLUSIONS: Although this study does not separate the prenatal and postnatal effects of smoking, these findings indicate that environmental tobacco smoke in the early postnatal period adversely affects pro-oxidative/antioxidative status within weeks of life in very early infancy.

Lupin-enriched bread increases satiety and reduces energy intake acutely.

BACKGROUND: Protein and fiber may be important determinants of satiety. Lupin kernel flour is a novel food ingredient that is rich in protein and fiber. OBJECTIVE: The objective was to investigate the effects of lupin kernel flour-enriched bread (LB) on satiety and energy intake in humans. DESIGN: Two randomized controlled crossover trials were performed to compare the acute effects of LB with those of white bread (WB). In study 1, the subjects (n = 16) completed 4 treatments 1 wk apart: WB breakfast (as toast) and WB lunch (as sandwiches), WB breakfast and LB lunch, LB breakfast and WB lunch, and LB breakfast and LB lunch. Energy intake at all breakfast meals was matched (1655 kJ), and ad libitum energy intake at lunch, 3 h after breakfast, was measured. In study 2, the subjects (n = 17) completed 2 treatments 1 wk apart: WB breakfast and LB breakfast (each 1655 kJ). Blood samples were taken at baseline and at regular intervals for 3 h after breakfast. RESULTS: In study 1, the LB breakfast resulted in significantly higher self-reported satiety (P < 0.001) and lower energy intake (kJ) at lunch (-488; 95% CI: -798, -178) than did the WB breakfast. The LB lunch resulted in a significantly lower within-meal energy intake (kJ) at lunch (-1028; 95% CI: -1338, -727) than did the WB lunch. In study 2, compared with the WB breakfast, the LB breakfast significantly altered the 3-h postmeal plasma ghrelin response (P = 0.04) and resulted in significantly lower mean 3-h plasma ghrelin concentrations (P = 0.009). CONCLUSION: A novel food enriched in protein and fiber derived from lupin kernel flour significantly influences energy intake acutely.

Red wine and beer elevate blood pressure in normotensive men.

A positive relationship between alcohol consumption and blood pressure (BP) is well-established but the relative effect of specific alcoholic beverages is controversial. This study aimed to determine whether red wine may improve vascular function and have less of an impact on blood pressure because of its high content of antioxidant vasodilator polyphenolic compounds. Healthy normotensive men entered a 4-period crossover study comparing in random order 4 weeks of control-abstinence with similar periods of daily consumption of red wine (375 mL; 39 grams alcohol), de-alcoholized red wine (375 mL), or beer (1125 mL; 41 grams alcohol). Ambulatory systolic BP and diastolic BP and heart rate (HR) were measured together with vascular function as assessed by flow-mediated dilatation (FMD) and glyceryl trinitrate-mediated (GTNMD) dilatation of the brachial artery. The systolic and diastolic BP and HR were not different between control-abstinence and de-alcoholized red wine. However, compared with control-abstinence, both red wine and beer increased awake systolic BP (2.9 and 1.9 mm Hg, respectively; P<0.05) and asleep HR (5.0 and 4.4 bpm; P<0.05). There were no specific effects of red wine, de-alcoholized red wine, or beer on FMD or GTNMD. Daily consumption of approximately 40 grams alcohol as either red wine or beer for 4 weeks results in similar increases in systolic BP and HR. De-alcoholized red wine did not lower BP, and neither red wine nor de-alcoholized red wine influenced vascular function, suggesting that red wine polyphenolics do not have a significant role in mitigating the blood pressure-elevating effects of alcohol in men.