Effect of Hemodialysis on the Content of Fatty Acids in Monolayers of Erythrocyte Membranes in Patients with Chronic Renal Failure

Lipid metabolism disorders are found in patients with chronic renal failure (CRF). Changes in the content of fatty acids of the phospholipid fraction of erythrocyte membranes can lead to changes in the rheological properties. The objective of our study was to assess the effect of hemodialysis on the composition of fatty acids in two fractions of phospholipids: sphingomyelin (SPH, representative of the external monolayer) and phosphatidylethanolamine (PE, representative of the internal monolayer). Venous blood was drawn from patient with CRF before and after the HD procedure. Lipids from the erythrocyte stroma were extracted using the Rose and Oklander method and then were separated into phospholipid fractions using thin-layer chromatography (TLC). PE and SPH fractions were extracted, and the fatty acid profile was determined using gas chromatography (Perkin Elmer 8400; RTx 2330 column; length: 105 m). In the phospholipid fractions tested, a high content of saturated FA with a medium carbon chain (C 16:0 to C 18:2) and a long carbon chain such as C 24:0, C 24:1; C 22:6; and C 26:0 was found. The HD procedure affected the FA profile in the fractions tested. The proportion of saturated and unsaturated long-chain FA (above 18 C) increased in PE. However, the content of medium-chain FA C 16:0 to C 18:1 decreased. A significant decrease in the content of the majority of long-chain FA could be noted in SPH. The ratio of unsaturated (U) to saturated (S) fatty acids in the SPH fraction increased. Hemodialysis has a significant effect on the content of fatty acids in the PE and SPH fractions of erythrocyte membranes in patients with CRF.     

Plasma Fatty Acid Composition in Continuous Ambulatory Peritoneal Dialysis Patients: An Increased Omega-6/Omega-3 Ratio and Deficiency of Essential Fatty Acids

Abstract

Patients with end-stage renal disease, including those treated with peritoneal dialysis, have a high risk for death, particularly from cardiovascular causes. Plasma fatty acid (FA) composition is used as an indicator of disease risk, because its alteration has been related to metabolic disease and cardiovascular disease. For this purpose, we have measured plasma FA composition in continuous ambulatory peritoneal dialysis (CAPD) patients and compared them with those of healthy subjects. This study was performed on 51 (21 M, 30 F) CAPD patients at least 6 months under dialysis, aged 20–75 years (mean 47.81 ± 11.8 years) and 45 (25 M, 20 F) healthy control subjects aged 20–60 years (mean 38.62 ± 12.9 years). Plasma 10-cis-pentadecanoic acid, 10-cis-heptadecanoic acid, heneicosanoic acid, tricosanoic acid, nervonic acid, saturated fatty acid, and monounsaturated FA levels and delta 9 desaturase activity were significantly higher whereas linoleic acid, linolenic acid, 11,14-eicosedienoic acid, arachidonic acid, docosahexaenoic acid, and omega-3 FA levels were significantly lower in the CAPD group than those in the healthy group. Our results show that there are FA abnormalities and especially a depletion in essential FA levels and a high level of omega-6/omega-3 ratio in CAPD patients, the underlying mechanism of which is not known and needs to be investigated. Therefore, we believe that essential FA supplementation should be encouraged for CAPD patients.     

Effects of Omega-3 Fatty Acids on Serum Lipids,Lipoprotein (a), and Hematologic Factors in Hemodialysis Patients

Abstract

Background: Lipid abnormalities, especially high serum lipoprotein (a) [Lp (a)] concentration, and anemia are two major causes of cardiovascular diseases (CVDs) in hemodialysis patients. Therefore, this study was designed to investigate the effects of marine omega-3 fatty acids on serum lipids, Lp (a), and hematologic factors in hemodialysis patients. Methods: Thirty-four hemodialysis patients were randomly assigned to either omega-3 fatty acid supplement or placebo group. Patients in the omega-3 fatty acids group received 2080 mg marine omega-3 fatty acids, daily for 10 weeks, whereas the placebo group received a corresponding placebo. At baseline and the end of week 10, 7 mL blood was collected after a 12- to 14-h fast and serum triglyceride, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), Lp (a), blood hemoglobin, hematocrit, red blood cells (RBCs), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were measured. Results: Serum triglyceride decreased significantly in the omega-3 fatty acids group at the end of week 10 compared with baseline (p < 0.05) and this reduction was significant in comparison with the placebo group (p < 0.01). No significant differences were observed between the two groups in mean changes of serum total cholesterol, LDL-C, HDL-C, Lp (a), blood hemoglobin, hematocrit, RBC, MCV, MCH, and MCHC. Conclusion: The results of our study indicate that marine omega-3 fatty acids can reduce serum triglyceride, as a risk factor for CVD, but it does not affect other serum lipids, Lp (a), and hematologic factors in hemodialysis patients.     

Relationship among Adiponectin, Adiponectin Gene Expression and Fatty Acids Composition in Morbidly Obese Patients

Background he aim of this study was to examine the relationship between adiponectin plasma circulating levels and its gene expression in two abdominal fat depots (subcutaneous and visceral) with the fatty acid composition of plasma and adipose tissue in morbidly obese subjects. Methods 20 patients (10 women and 10 men) were selected. All were morbidly obese (BMI ≥40 kg/m²) and admitted for gastric surgery. Plasma samples and adipose tissue from both subcutaneous and visceral regions were obtained. Plasma adiponectin and adipose adiponectin expression were analyzed. Results Adiponectin mRNA expression in the subcutaneous tissue was significantly higher (P = 0.048) than in visceral tissue. Circulating adiponectin values, were positively associated with the proportion of n-3 polyunsaturated fatty acids in plasma (r = 0.62, P = 0.002). The visceral depot showed greater statistical associations between adiponectin gene expression and fatty acids profile, being saturated fatty acids associated with a decrease (r = −0.68, P = 0.015), whereas monounsaturated were related to an increase in this adipose region (r = 0.67, P = 0.017). Conclusions e demonstrated significant associations between adipose tissue adiponectin gene expression and fatty acid composition. These associations were more evident in relation to the visceral depot, an adipose tissue region highly implicated in the metabolic syndrome.     

番茄籽油的脂肪酸及甘油酯组成分析

采用柱层析、气相色谱法和薄层层析法 ,研究了国内常见的几种番茄籽中油脂含量、脂肪酸组成和甘油酯的结构 .番茄籽油含油率为 2 0 %～ 2 3 % ,不饱和脂肪酸质量分数在 70 %以上 ,其中必需脂肪酸———亚油酸质量分数为 50 %以上 .番茄籽油是一种优质食用油 .     

Polyunsaturated Fatty Acids in Relation to Sperm Motility

The absolute amounts of phospholipid-linked fatty acids of different andrological conditions were analyzed by gas-liquid-chromatography. There was a significant linear correlation between docosahexaenoic acid and the spermatozoal density. Similarly there was a significant correlation between the content of docosahexaenoic acid and the number of motile normal sperm. These findings suggest that the process of lipid peroxidation is probably one of the biochemical causes of the low docosahexaenoic acid content in poorly motile sperm.     

分子蒸馏法制备鱼油多不饱和脂肪酸

研究了多级分子蒸馏法提取深海鱼油中多不饱和脂肪酸的工艺方法,通过对压力和温度的控制得到不同多不饱和脂肪酸含量的各级鱼油产品,当蒸馏温度为110℃以上,蒸馏压力为20Pa以下时,经过三级串联分子蒸馏,得到高碳链不饱和脂肪酸质量分数为90.96%的鱼油产品,并用气相色谱法测定了产品的脂肪酸组成,分析了产品的理化指标.     

Relation Between Echinocytosis and Erythrocyte Calcium Content in Hemodialyzed Uremic Patients

A rise in intracellular calcium concentration in erythrocytes has multiple effects on these cells. The purpose of this study was to determine the changes of calcium content in red blood cells (RBCs) and of echinocyte percentages in uremic patients during hemodialysis sessions. In 30 uremic patients under hemodialysis, the calcium content of RBCs and echinocyte percentages were determined in 3 blood samples collected at 0 min hemodialysis (prehemodialysis), 45 min hemodialysis, and 240 min hemodialysis (end hemodialysis) for a 4 h hemodialysis session. Calcium content of RBCs and echinocytes were also determined in 22 normal subjects (controls). The findings of the present study were that the mean values (+/-SD) of calcium content of RBCs in patients at 0 min hemodialysis, 45 min hemodialysis, and 240 min hemodialysis were 2.00 +/- 1.0, 2.66 +/- 0.87, and 1.62 +/- 0.66 microg/ml respectively and 0.65 +/- 0.07 microg/ml in controls. These values show that the calcium content of RBCs in uremic patients at 0 min hemodialysis, 45 min hemodialysis, and 240 hemodialysis was significantly higher than in controls (p < 0.0001), and that RBC calcium content at 45 min hemodialysis was significantly higher in comparison to that at 0 min hemodialysis (p < 0.001) and to that at 240 min hemodialysis (p < 0.0001), while that at 240 min hemodialysis was significantly lower than at 0 min hemodialysis (p < 0.05). The mean values (+/-SD) of echinocyte percentages in patients at 0 min hemodialysis, 45 min hemodialysis, and 240 hemodialysis were 11.93 +/- 6.18, 17.23 +/- 4.1, and 7.96 +/- 5.67% respectively, and in controls ranged from 0 to 1%. The values in uremic patients show a transient increase of echinocyte percentages at 45 min hemodialysis, which is significant in comparison to that at 0 min hemodialysis (p < 0.001) and to that at 240 min hemodialysis (p < 0.0001). Echinocyte percentages at 240 min hemodialysis were significantly lower to those at 0 min hemodialysis (p < 0.001). Correlation between calcium content of erythrocytes and echinocyte percentages shows a significantly positive relationship at 45 min hemodialysis (r = 0.368, p < 0.05) but no significant relationship at 0 min hemodialysis and 240 min hemodialysis. In conclusion, uremic patients under hemodialysis present with high calcium content in erythrocytes and abnormal erythrocytes like echinocytes. A rapid and transient increase of erythrocyte calcium is also accompanied by transient elevation of echinocytes in the first hour of hemodialysis (45 min hemodialysis), which returns after hemodialysis to lower than prehemodialysis levels.     

游离脂肪酸对大鼠肾小球系膜细胞增殖和细胞周期的影响

目的：探讨游离脂肪酸（FFAs）对体外培养的大鼠肾小球系膜细胞增殖和生长周期的影响。方法：用不同浓度的游离脂肪酸处理大鼠HBZY-1细胞株（即大鼠肾小球系膜细胞）24h～72h。采用噻唑蓝比色（MTT）法检测内皮细胞增殖情况,流式细胞术（FCM）分析法测定细胞周期变化。结果：游离脂肪酸可抑制HBZY-1细胞的生长增殖（与对照组比较,P〈0.01）,且这种抑制作用具有剂量和时间依赖性;游离脂肪酸作用于HBZY-1细胞24h、48h、72h,细胞周期发生明显改变,G1期细胞数增多,S期细胞数减少（与对照组比较,P〈0.01）。结论：游离脂肪酸可通过停滞细胞生长于G1期,抑制大鼠肾小球系膜细胞的生长增殖。     

Impact of Supplementing Preoperative Intravenous Omega 3 Fatty Acids in Fish Oil on Immunomodulation in Elderly Patients Undergoing Hip Surgery

The aim of this study was to evaluate the immunomodulatory effects of supplementing intravenous omega-3 fatty acids in fish oil (IVFO) in elderly patients undergoing hip surgery. This was a single centre, randomized, controlled, comparative, phase IV study in elderly patients undergoing hip surgery. The subjects, within the age range of 50–90 years, were assigned randomly to the group receiving intravenous omega-3 fatty acids in fish oil (IVFO, Omegaven®) or the control group not receiving intravenous fish oil (n = 20 in each group). IL-6, IL-8, IL-10, and HS-CRP levels were the inflammatory markers assessed in this study. The within-group comparison was done by paired t-test and between-group comparison by unpaired t-test. At day 4, IL-6 values in the IVFO group decreased as compared to day 0. At day 4, IL-8 mean values increased for both IVFO and control groups. This increase was highly significant in the control group (P = 0.0182). IL 10 values decreased at day 4 and increased at day 8 in the IVFO group. Increase in HS-CRP levels was nonsignificant at day 4 in the IVFO group (P = 0.60) and significant at day 8 for the control group (P = 0.0084) as compared to day 0. Various biochemical parameters including albumin, protein, SGOT, SGPT, blood glucose, and urea values generated evidence regarding the safety profile of IVFO. This study suggests a role for IVFO in the short-term suppression of inflammatory mediators for patients undergoing hip surgery. However, further, larger trials may be needed to establish its definitive role in this patient population.     

Effects of Thoracic Epidural Analgesia on Cardiovascular Function and Plasma Concentration of Free Fatty Acids and Catecholamines in the Dog

Increased plasma levels of free fatty acids (FFA), leading to increases in the myocardial oxygen demand, are seen after, for example, surgical stress, traumas and myocardial infarction. The present study was undertaken to investigate the cardiovascular effects of thoracic epidural analgesia (TEA) and the effect of TEA on the plasma concentration of FFA and catecholamines. In 10 sodium-pentobarbital-anaesthetized dogs the local anaesthetic agent bupivacaine was injected into the thoracic epidural space via a surgically introduced catheter. TEA markedly reduced heart rate, mean aortic blood pressure, left ventricular systolic blood pressure and dP/dtmax. TEA reduced the plasma concentration of FFA. The FFA-lowering effect was greatest when the FFA values were high. The effect of TEA on the plasma concentration of noradrenaline and adrenaline was inconsistent and seemed to be of minor importance for the haemodynamic and FFA effects of TEA. The study indicates that TEA, by its haemodynamic and FFA-lowering effects, may reduce myocardial oxygen demand.     

Plasma Lipids and Fatty Acid Levels in Chronically Uremic Patients Undergoing Blood Purification with Different Methods

Levels of plasma lipids and the fatty acid composition of major plasma lipid classes have been determined in chronically uremic patients before and after treatments with hemofiltration, high efficiency paired filtration dialysis, or acetate-free biofiltration. The major findings are a decrease of triglycerides and an increase of total free fatty acids (FFAs) at the end of the dialytic session--already reported in the literature--that do not appear to be strictly dependent on heparin administration. The changes in the plasma concentrations of selected saturated and polyunsaturated fatty acids, which may contribute to alteration of functional parameters in the cardiovascular system in dialyzed patients, are different in the various types of techniques.     

Free Amino-Acid Composition of Human Seminal Plasma in Different Andrological Diagnoses

Der Gehalt an f reien Aminosäuren im menschlichen Spermaplasma bei verschiedenen andrologischen Diagnosen
Der Gehalt an freien Aminosäuren des menschlichen Seminalplasmas wurde 30 min nach der Ejakulation bestimmt. Die Hauptbestandteile sind Serin, Threonin und Tyrosin. Ein Vergleich des Aminosäuregehaltes von vier andrologischen Diagnosen deutet auf eine Verknüpfung von freien Aminosäuren und Spermatozoen hin.     

Successful Declotting of Arteriovenous Grafts with Local Infusion of Urokinase in Hemodialyzed Patients

Local infusion of urokinase was used in 15 cases of thrombotic occlusion of polytetrafluoroethylene grafts in 10 hemodialyzed patients. The treatment was successful in all patients except one in whom recurring thrombosis occurred because of junctional stenosis at the venous anastomosis. No relevant side effects were observed. Follow-up data show that such treatment can significantly prolong the survival of arteriovenous grafts in hemodialyzed patients with otherwise difficult access to the circulation.     

Dialysis Modalities and HDL Composition and Function

Lipid abnormalities may have an effect on clinical outcomes of patients on dialysis. Recent studies have indicated that HDL dysfunction is a hallmark of ESRD. In this study, we compared HDL composition and metrics of HDL functionality in patients undergoing hemodialysis (HD) or peritoneal dialysis (PD) with those in healthy controls. We detected a marked suppression of several metrics of HDL functionality in patients on HD or PD. Compositional analysis revealed that HDL from both dialysis groups shifted toward a more proinflammatory phenotype with profound alterations in the lipid moiety and protein composition. With regard to function, cholesterol efflux and anti-inflammatory and antiapoptotic functions seemed to be more severely suppressed in patients on HD, whereas HDL-associated paraoxonase activity was lowest in patients on PD. Quantification of enzyme activities involved in HDL metabolism suggested that HDL particle maturation and remodeling are altered in patients on HD or PD. In summary, our study provides mechanistic insights into the formation of dysfunctional HDL in patients with ESRD who are on HD or PD.