Ileal and colonic fatty acid profiles in patients with active Crohn's disease.

In patients with active Crohn's disease and in a control group the fatty acid profiles in the whole lipid fraction of ileal and colonic mucosal biopsy specimens were determined by capillary gas chromatography. The biopsy specimens in Crohn's disease patients were taken from the inflamed terminal ileum as well as from the inflamed and macroscopically normal colon. Compared with controls the fatty acid distribution in the inflamed ileal mucosa was significantly characterised by (a) a decrease of 18:2 n6 and 18:3 n3 accompanied by a substantial increase of the highly polyunsaturated fatty acids 20:4 n6, 22:4 n6, and 22:6 n3 and (b) a higher unsaturation index of total fatty acids compared with controls. These changes were similar in the inflamed colon. Additionally, both the inflamed and the macroscopically normal colonic mucosa showed an increase of saturated (18:0) and a decrease of monounsaturated fatty acids (18:1 n9). Fatty acid profiles of ileum and colon showed side variations in controls, but not in the Crohn's disease group. These data suggest that in Crohn's disease changes in the distribution of polyunsaturated fatty acids seem to be the general feature of inflamed mucosa in small and large intestine. Results further suggest that colonic fatty acid metabolism in Crohn's disease is altered by degrees, showing changes in saturated and monounsaturated fatty acids as an additional, primary event.     

Effects of dietary fish oil on lung phospholipid fatty acid composition and intrinsic pulmonary vascular reactivity

A fish oil diet has been shown to lower systemic blood pressure in man and alter vascular reactivity to exogenous noradrenaline in man and rats. The effects of a fish oil diet on the vascular reactivity of the pulmonary circulation have not been assessed. The effect of dietary lipid composition on pulmonary artery pressure and vascular reactivity of 30 adult male Sprague-Dawley rats (250-300 g) was assessed in vivo (n = 9) and in the isolated perfused lung (n = 21). Isocaloric diets containing 20% lipid (% by weight) as fish oil, corn oil, or lard were given in unlimited quantities to the rats. After one month of the diet, pulmonary vascular reactivity to angiotensin II (0.15 micrograms) and hypoxia (fractional inspired oxygen 0.025) were assessed in the isolated perfused rat lung. The haemodynamic effects of the diet on resting normoxic pulmonary artery pressure (in vivo) were assessed in chloralose anaesthetised rats. The fish oil diet appreciably increased the content of eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) in lung phospholipids but had no effect on pulmonary vascular reactivity. The arachidonic acid (C20:4) content of the lung was considerably decreased. Platelet counts were lower in the rats fed fish oil. The study indicates that a fish oil diet does not alter acute intrinsic pulmonary vascular reactivity despite pronounced changes in lung phospholipid fatty acid profile.     

Effects of a fish oil concentrate in patients with hypercholesterolemia

The effects of a fish oil supplement on lipid and lipoprotein levels, platelet function, and vital signs were investigated in 31 hypercholesterolemic patients. Thirteen patients took 5 g of encapsulated fish oil per day and 18 patients took 5 g of encapsulated safflower oil "placebo" per day for 28 days. Diet and exercise patterns were kept as constant as possible during the study. The fish oil group had significant increases in several lipid/lipoprotein values at the end of the treatment, including an increase of total cholesterol of 14% (P = 0.0001), LDL of 16% (P = 0.003), HDL of 13% (P = 0.015) and HDL2 of 36% (P = 0.009). The triglyceride level fell 24%, a nonsignificant change (P = 0.217). The ratios of total cholesterol/HDL and LDL/HDL were increased at the end of fish oil treatment, and returned to baseline 30 days after fish oil was stopped. The placebo group had no significant changes in any of the lipid/lipoprotein values. Neither the fish oil nor the placebo group had significant changes in vital signs or platelet function tests (bleeding time, thromboxane B2, platelet factor 4 and beta-thromboglobulin) during the study. These results suggest that fish oil supplements may have an adverse effect on lipid/lipoprotein values in hypercholesterolemic patients.     

Plasma phospholipid fatty acid pattern in severe liver disease

BACKGROUND/AIMS: In acute liver failure the liver has to regenerate, which may increase the consumption of essential fatty acids. Nutritional support consists mainly of infusion of glucose. It is therefore possible that essential fatty acid deficiency may develop in such patients. METHODS: Plasma phospholipid composition was studied in healthy controls (n=11), in patients with acute liver failure, (n=10), in patients with stable cirrhosis (n=7), and in patients with acute on chronic liver disease with hepatic encephalopathy (n=6). The influence of 2 days of fat-free diet followed by infusion of glucose was studied in five healthy controls. RESULTS: The ratio between the sums of nonessential/ essential fatty acids, (n-7+n-9)/(n-3+n-6), was higher in patients with acute liver failure (0.73+/-0.17) compared to healthy controls (0.35+/-0.06, p<0.001). The ratio was also higher in patients with acute on chronic liver disease (1.11+/-0.39) compared to patients with cirrhosis (0.61+/-0.18, p<0.01). These differences were mainly due to low levels of linoleic acid and high levels of oleic acid in the patients with acute liver failure and acute on chronic liver disease. Two days of fat-free diet followed by infusion of glucose did not change this ratio (0.40+/-0.04 vs. 0.47+/-0.05, NS) in healthy controls. The essential fatty acid deficiency indicator eicosatrienoic acid was detectable in 2 out of 11 controls, in 5/10 with acute liver failure, in 7/7 with cirrhosis, and in 6/7 with acute on chronic liver disease. CONCLUSION: Acute severe deterioration of liver function was associated with changes in the fatty acid composition of plasma phospholipids suggestive of essential fatty acid deficiency.     

Effects of two types of fish oil supplements on serum lipids and plasma phospholipid fatty acids in coronary artery disease

Fish oil has consistently been shown to lower triglyceride levels, but its effects on low-density lipoprotein (LDL) cholesterol remain controversial. The current study compares the long-term effects of 2 different fish oil preparations (ethyl ester and triglyceride) versus olive oil in patients with coronary artery disease. Eighty-nine subjects were randomly assigned to receive capsules containing 6 g/day (triglyceride group) or 7 g/day (ethyl ester group) of n-3 fatty acids, or capsules containing 12 g/day of olive oil for 6 months. Mean triglyceride levels decreased by 28% in the ester and 32% in the triglyceride fish oil groups (p less than 0.05 for both). LDL cholesterol levels increased by 3% (difference not significant) in the ester and 12% (p less than 0.05) in the triglyceride fish oil groups; in hypertriglyceridemic subjects the increase was 23% (p less than 0.01) and 14% (difference not significant), respectively. Plasma phospholipid fatty acid analysis showed a fivefold increase in eicosapentaenoic acid levels in both fish oil groups (p less than 0.001), and a long-term decrease in arachidonic acid levels (p less than 0.001). Achieved eicosapentaenoic acid level correlated with the degree of increase in LDL cholesterol (r = 0.38, p less than 0.05). These data suggest that fish oil administration is associated with an increase in LDL cholesterol levels in a diverse group of patients with coronary artery disease; this change appears to be correlated with n-3 fatty acid absorption. The impact of this increase in LDL is unknown, but should be considered as potentially adverse.     

Transformation of chenodeoxycholic acid to ursodeoxycholic acid in patients with Crohn's disease

In vivo 7 beta-epimerization of chenodeoxycholic acid to ursodeoxycholic acid and the role of 7-ketolithocholic acid as an intermediate in this biotransformation were studied in 11 patients with Crohn's disease and in 5 healthy volunteers. The incorporation of deuterium into biliary ursodeoxycholic acid and 7-ketolithocholic acid was determined by computed gas chromatography-mass fragmentography after ingestion of a dideuterated chenodeoxycholic acid, chenodeoxycholic-11,12-d2 acid. The incorporation of deuterium into ursodeoxycholic acid increased to a peak level at 48 h in the patients with Crohn's disease, but was delayed in healthy volunteers. In 8 patients and 2 healthy controls there were small amounts of 7-ketolithocholic acid in bile. The incorporation of deuterium into 7-ketolithocholic acid was confirmed in only 2 patients and the peak level was noted at 48 h. These observations suggest that 7-ketolithocholic acid is an intermediate of this biotransformation in patients with Crohn's disease.     

Effects of dietary butter fat on fecal bile acid excretion in patients with Crohn's disease on elemental diet

The excretion rate of fecal bile acids was determined by gas-liquid chromatography in nine patients with Crohn's disease and six healthy volunteers under two dietary conditions with different amounts of fat: during nasoduodenal tube feeding with a fat-restricted elemental diet containing approximately 1.5 g/day of fat, and during the addition of 50 g/day of butterfat by peroral administration. The fecal bile acid excretion rate on the elemental diet was significantly greater in the patients with Crohn's disease than in the healthy controls. With ingestion of the additional fat, the excretion rate was significantly increased in the patients with Crohn's disease, but not significantly changed in the healthy controls. The bile acid excretion rate in Crohn's disease correlated with fecal fat excretion, but not with either fecal weight or disease activity. These studies show that the amount of dietary fat represents an important consideration in the evaluation of bile acid malabsorption in Crohn's disease.This work was supported in part by a grant from Clinical Medicine Promoting Foundation, Fukuoka City, Japan.     

Effects of a fish oil supplement on blood pressure and serum lipids in patients treated for coronary artery disease.

OBJECTIVE: The purpose of this study was to evaluate the effects of a concentrate of fish oil on blood pressure and serum lipids in patients treated for coronary artery disease. DESIGN: One hundred and twenty-five patients were randomly assigned to receive 15 g/day MaxEPA (4.5 g eicosapentaenoic and docosahexaenoic acids) or olive oil. Blood pressure and serum lipids were measured at enrollment and six months thereafter. MAIN RESULTS: As an important proportion of antihypertensive or antianginal drug users stopped their usual medication during the trial, blood pressure increased in both groups. The increase in systolic blood pressure was less in the fish oil group than in the control group (P = 0.002). Serum triglyceride levels decreased markedly in the fish oil group while they remained constant in the control group (P = 0.0001). Fish oil supplementation had no effect on total cholesterol and only marginal independent influence on high density lipoprotein and low density lipoprotein cholesterol levels. CONCLUSIONS: In conclusion, fish oil supplementation has a beneficial effect on blood pressure and serum triglycerides in patients treated for coronary artery disease.     

Purified fish oil eliminating linoleic and alpha linolenic acid meets essential fatty acid requirements in rats

This study examined whether purified fish oil (PFO) supplemented to an essential fatty acid deficient (EFAD) diet meets EFA needs in rats. The EFAD diet contained 10% hydrogenated coconut oil (HCO). A similar diet contained 7% HCO and 3% PFO which also provided 2.84% arachidonic acid (AA), 52.50% eicosapentaenoic acid (EPA) and 35.73% docosahexaenoic acid (DHA) but no linoleic acid (LA) or alpha linolenic acid (ALA). A 10% soybean oil control diet provided ample LA and ALA. After 4 weeks of feeding, blood glucose, plasma triglyceride and phospholipid fatty acid profiles, C-reactive protein (CRP), TNF and IL-6 were determined after saline or LPS injection. EFAD developed with the HCO diet with triene:tetraene ratios in plasma phospholipids >.20, which remained <.02 with the control and HCO+PFO diets. Mead acid levels significantly increased by a factor of 10 with the HCO diet compared to the AIN and HCO+PFO diets and were significantly lowest with the HCO+PFO diet. 18:1 n9 levels were significantly higher in plasma phospholipids and triglycerides with the HCO diet. CRP levels were significantly highest with the control diet and significantly lowest with the HCO diet. LPS significantly increased 18:1n9 and cytokines, and decreased AA and plasma glucose in all diets and significantly increased plasma triglycerides and decreased plasma glucose in controls. Providing AA, EPA and DHA in EFAD prevents EFAD over the short-term as reflected in Mead acid production, triene:tetraene ratio, and de novo lipogenesis and may reduce the inflammatory response to LPS.     

Plasma polyunsaturated fatty acid pattern in active inflammatory bowel disease.

Plasma fatty acid patterns were assessed by gas liquid chromatography in 73 patients with active inflammatory bowel disease and 107 healthy controls. The influence of the disease activity on fatty acid profile was also investigated. Plasma fatty acid patterns in patients with ulcerative colitis and Crohn's disease were similar. Plasma C18:3n3 and C22:6n3 were significantly higher in active ulcerative colitis (p = 0.0143 and p < 0.00001 respectively) and in Crohn's disease (p < 0.00001 for both) than in controls, whereas C20:3n6 was significantly lower in patients than in controls, both in ulcerative colitis (p = 0.0001) and in Crohn's disease (p = 0.0041). In more severe disease, plasma polyunsaturated fatty acid concentrations fell with a significant stepwise decrease in the desaturation index (p = 0.0031 in ulcerative colitis and p = 0.0355 in Crohn's disease). Even in patients with severe disease, however, plasma n3 fatty acids (C18:3n3 and C22:6n3) never fell below those of healthy controls. These findings suggest that in active inflammatory bowel disease, an increased biosynthesis might coexist with an increased consumption of polyunsaturated fatty acids. These observations may be of relevance in the pathogenesis of the disease as polyunsaturated fatty acids are involved in tissue eicosanoid synthesis and cellular membrane function, including that of immunocompetent cells. These results also question the rationale of using n3 polyunsaturated fatty acids in the treatment of inflammatory bowel disease.     

Analysis of omega-3 fatty acid content of South African fish oil supplements

Introduction

Substantial evidence describes the protective effects of marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFA) on cardiovascular diseases as well as many other conditions. Numerous fatty acid preparations are marketed for supplementing the Western diet, which is low in n-3 fats. Since these preparations may vary in their n-3 PUFA content, we tested 45 commercially available products on the South African market for their fatty acid composition.

Method

Forty-five commercially available n-3 fatty acid supplements were analysed using gas–liquid chromatography to determine their fatty acid content.

Results

More than half of the n-3 supplements available on the South African market contained ≤ 89% of the claimed content of EPA and/or DHA as stated on the product labels. To meet ISSFAL’s recommendation of 500 mg EPA + DHA/day can cost consumers between R2 and R5 per person per day (R60 to R150 p/p/month). Regarding rancidity, the majority of capsules contained conjugated diene (CD) levels higher than that of vegetable oil obtained from opened containers (three months) used for domestic cooking purposes, despite the addition of vitamin E as antioxidant.

Conclusion

Since no formal regulatory structure for dietary supplements currently exists in South Africa, consumers depend on self-regulation within the nutraceutical industry for assurance of product quality, consistency, potency and purity. Our results indicate that more than half of the n-3 fatty acid supplements on the South African market do not contain the claimed EPA and/or DHA contents as stated on product labels, and they contained CD levels higher than that in unused vegetable oils obtained from opened containers used for domestic cooking purposes.     

Nutritional supplementation with N-3 fatty acids and antioxidants in patients with Crohn's disease in remission: effects on antioxidant status and fatty acid profile

In patients with Crohn's disease (CD), malnutrition is frequently observed and is generally accepted to be an important issue. The aim of this study was to investigate the effects of 3 months of supplementation with a liquid formula containing either antioxidants (AO) or n-3 fatty acids plus AO on the antioxidant status and fatty acid profile of plasma phospholipids and adipose tissue, respectively, in patients with long-standing CD currently in remission. In a randomized, double-blind placebo-controlled study, CD patients received either placebo, AO, or n-3 fatty acids plus AO for 3 months in addition to their regular diet. In all, 25/37 CD patients completed the study. AO status was assessed by blood biochemical parameters. A statistical per-protocol analysis was performed. Serum concentrations of selenium, vitamin C, and vitamin E, the activity of superoxide dismutase and total antioxidant status were significantly (p < 0.05) increased after AO supplementation. Furthermore, compared with controls, serum concentrations of beta-carotene, selenium, and vitamin C and the activity of glutathione peroxidase (GPx) were significantly (p < 0.05) lower before supplementation; however, after AO supplementation these levels were not significantly different from controls (except for GPx). N-3 fatty acids plus AO supplementation significantly (p < 0.05) decreased the proportion of arachidonic acid, and increased the proportion of eicosapentanoic acid and docosahexanoic acid in both plasma phospholipids and adipose tissue. Supplementation with antioxidants improved antioxidant status in patients with CD in remission. In addition, supplementation with n-3 fatty acids plus antioxidants significantly changed the eicosanoid precursor profile, which may lead to the production of eicosanoids with attenuated proinflammatory activity. This study indicates that an immunomodulating formula containing n-3 fatty acids and/or AO may have the potential to play a role in the treatment of CD.     

Mucosal-associated bacterial flora of the intestine in patients with Crohn's disease and in a control group

The bacterial flora intimately associated with the intestinal mucosa of patients with Crohn's disease has been examined and compared with the mucosal flora of a control group. Specimens were obtained at operation from patients undergoing intestinal surgery. Whole thickness intestinal sections were taken from the diseased segment and from a portion of uninvolved intestine from patients with Crohn's disease as well as from a control group. A section of each specimen was examined histologically. Twenty-two specimens of Crohn's tissue (12 ileum, 10 colon) and 46 control samples from small and large bowel were examined using strictly anaerobic bacteriological techniques in an anaerobic chamber. Organisms were grown under both aerobic and anaerobic conditions. A mucosal flora was found to exist in all the large bowel samples and in three-quarters of the small bowel samples. It was qualitatively similar in all the samples, consisting mainly of Gram positive bacteria, aerobic Gram negative rods and bacteroides. Greater numbers of bacteria were associated with colonic tissue (10⁷ - 10⁸ per g) than with tissue from the jejunum (10³ - 10⁴ per g). This difference was statistically significant (p<0·03). Samples from the terminal ileum were quantitatively intermediate between jejunum and colon. There was no statistical difference in the numbers of bacteria associated with Crohn's tissue compared with histologically normal tissue from the same patients and from the control group of patients. Among the bacterial isolates, however, Enterobacteria were more commonly associated with Crohn's tissue.     

鱼油对ARDS患者预后影响的Meta分析

目的：评价鱼油对 ARDS 患者预后的影响。方法计算机及手工检索 PubMed、Embase、Cochrane图书馆临床随机对照试验资料库、Highwire、中国生物医学文献数据库、中国学术期刊全文数据库(CNKI)、万方数据库,并在互联网检索正在进行的试验：Current Controlled Trial (www.controlled-trials.com)和美国国立卫生研究院临床试验数据库(www.clinicaltrials.gov)。按Cochrane系统评价的方法,选择试验、评价质量,使用 Review Manager 5.2软件进行 Meta 分析。结果共纳入7项随机对照临床试验,包括994例研究对象。与非鱼油添加组相比：鱼油未能降低ARDS患者28 d病死率(RR =0.81,95%CI ：0.56~1.18,P =0.27);鱼油未能减少 ARDS 患者28 d机械通气时间(WMD=-2.06,95%CI ：-4.81~0.70,P=0.14);鱼油缩短 ARDS患者28 d内 ICU住院天数,且差异具有统计学意义(WMD=-2.47,95%CI ：-4.33~-0.60,P=0.009)。结论对于 ARDS患者,鱼油的摄入并不能降低病死率及缩短机械通气时间,但有助于减少 ICU 住院时间。     

Significance of serum sialic acid in patients with Crohn's disease.

Serum sialic acid was measured to evaluate the activity of Crohn's disease. The sialic acid levels of patients with Crohn's disease in remission (CRP 0.0 mg/dl) were significantly higher than those of healthy subjects and postoperative patients with Crohn's disease. In patients in remission, serum sialic acid was significantly correlated with hemoglobin, hematocrit, platelet, and rapid turnover protein. Correlations with platelet, retinol-binding protein, and prealbumin were especially strong. From these findings, it was concluded that serum sialic acid level provides a useful index of the activity of Crohn's disease.     

Bile acid metabolism in patients with Crohn's disease in terminal ileum

Bile acid metabolism was studied by means of the fractional turnover rate or orally ingested 14C-labeled taurocholic acid and by gas chromatographic determination of fecal excretion of the bile acids cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), and lithocholic acid (LCA). Thirty patients with Crohn's disease (CD) of the small bowel, of whom 19 had been operated on with limited ileal resections, were studied and compared with 11 healthy volunteers. The unoperated group of CD patients did not show significant increase in bile acid excretion in the stools in contrast to the CD patients with ileal resection. The fecal excretion consisted mostly of primary bile acids, and a significant correlation between length of resection and bile acid excretion was found (rs = 0.81, p less than 0.01). The fractional turnover rate of CA + DCA was significantly increased in both unoperated (0.21 l/day) and operated (0.44 l/day) patients compared with normal controls (0.06 l/day). The bile acid pool of CA + DCA, however, was normal in patients with ileal resections, indicating a compensatory increase in bile acid synthesis. In unoperated patients the bile acid pool of CA + DCA was slightly decreased (3.1 mmol) compared with operated patients (6.2 mmol) and normal controls (4.8 mmol). The pool size was not significantly correlated to mean transit time of dietary residue, feces excretion, loss of weight, or amount of fat in feces. The mean transit time of dietary residue was decreased in both operated and unoperated CD patients.