Erythrocyte Membrane Lipid Research Articles

OXIDATIVE STRESS IN THE PATIENTS WITH CKD V STAGE AND ANEMIA WHO RECEIVE REPLACEMENT HEMODIALYSIS THARAPY

The article presents research data of oxidative stress role in the pathogenesis of anemia in patients with CKD V stage, who receive hemodialysis replacement therapy.
 Background. Oxidative stress is a part of the pathogenesis of many complications in patients with CKD stage V on replacement therapy with hemodialysis. Anemia syndrome is the most frequent complication of this patient`s population.
 Aim. The aim of this study was to study indicators of oxidative stress in patients with CKD stage V and anemia on replacement therapy with hemodialysis.
 Materials and methods. We studied laboratory parameters in 42 hemodialysis patients with CKD V stage. Biochemical methods are used for investigation of lipid peroxidation processes: studied diene conjugates (DC), malondialdehyde (MDA), total lipids and catalase, lipid’s structure of erythrocytes membranes and their osmotic resistance.
 Results. We found that in dialysis patients anemic syndrome was associated with high activity of oxidative stress. Also increased destruction of red blood cells depends from high activity of oxidative stress. In the blood of the patients concentration of DC was 1,12±0,26 opt.den.units/ mg of lipids (p<0,01), and MDA level 0,35±0,05 opt.den.units/ mg of lipids (p<0,01). Levels of catalase, decreased to 0,029±0,0019 mm/l*sec (p<0,001). Also osmotic resistance of erythrocytes significantly decreased. MDA has inverse correlation relationship with hemoglobin in the blood, with a correlation coefficient r=-0,36. Investigation of erythrocyte membrane lipid structure of patients by TLC showed a significant decrease of phospholipids and monoglycerides of higher fatty acids, and the increase of cholesterol fractions.
 Conclusions. In patients with chronic kidney disease on dialysis replacement therapy anemic syndrome is associated with high activity of oxidative stress, as there is an inverse relationship between the level of hemoglobin and the content of MDA in blood. As a consequence of oxidative stress changes the lipid composition of erythrocyte membranes of the patient, because some fraction of lipids are substrates for oxidative processes. Impairment of lipid membranes of red blood cells of hemodialysis patients is one of the probably causes of anemia.

КЛЕТОЧНЫЕ ТЕХНОЛОГИИ В КОРРЕКЦИИ НАРУШЕНИЙ МЕТАБОЛИЗМА ЭРИТРОЦИТОВ ПРИ ОСТРОМ ТОКСИЧЕСКОМ ПОРАЖЕНИИ ПЕЧЕНИ

Цель. Установление эффективности использования аллогенных гепатоцитов и мексидола в коррекции нарушений содержания белков и липидов мембран и показателей метаболизма эритроцитов в условиях острого токсического поражения печени.Материалы и методы. Исследования проведены на 65 крысах-самцах Вистар. Острое токсическое поражение печени моделировали путем внутримышечного введения четыреххлористого углерода. Выделение аллогенных гепатоцитов от животных через 5–6 дней после рождения производилась по методике M.N. Berry, D.S. Friend. Мексидол вводили одновременно с токсикантом, пятикратно, через 24 часа, внутрибрюшинно в дозе 50 мг/кг отдельно или вместе с аллогенными гепатоцитами.Результаты. В статье изложены данные о нарушениях содержания белков и липидов мембран и показателей метаболизма эритроцитов у экспериментальных животных в условиях острого токсического поражения печени (ОТПП), вызванного введением четыреххлористого углерода. В работе определена эффективность использования аллогенных гепатоцитов и мексидола в коррекции нарушенных показателей липидного спектра мембран и метаболизма эритроцитов у животных при ОТПП.Заключение. Эффект мексидола при остром токсическом поражении печени обусловлен нормализацией липидного обмена в клеточной мембране и, соответственно, белкового спектра мембран.Область применения результатов. Полученные результаты могут быть использованы при разработке эффективных способов коррекции метаболических нарушений при различных видах патологии печени.

A Small Cohort Omega-3 PUFA Supplement Study: Implications of Stratifying According to Lipid Membrane Incorporation in Cardiac Surgical Patients.

Epidemiological studies and randomised clinical trials (RCTs) report disparate findings in relation to omega-3 polyunsaturated fatty acids (n-3 PUFA) benefit for cardiac patients. With RCTs interpretation is potentially confounded by background n-3 PUFA intake. The goal of this pilot, small cohort, pre-surgical supplementation study was to evaluate postoperative atrial fibrillation (AF) and cardiac molecular expression profiles employing two data analysis approaches - by treatment randomisation and by stratification using measured n-3 PUFA. Patients (n=20) received 3g/day of fish or placebo oil (FO vs PO) in a double blind randomised protocol prior to elective coronary artery graft and valve surgery. Groups were matched for age, gender, and mean treatment duration (∼20 days). Resected atrial myocardium was sampled for assay of viability metabolic markers, and blood obtained for erythrocyte membrane lipid measurement. There was substantial overlap of cell membrane n-3 PUFA content across PO and FO groups, and no group treatment effects on AF incidence or myocardial molecular marker levels were detected. In contrast, data stratification using membrane n-3 PUFA content (at 8% total membrane lipid) achieved significant separation of patients (by n-6:n-3 PUFA ratio), a significant differential cardiac expression of the marker peroxisomal proliferator-activated receptor, but no difference in AF incidence. This small n-3 PUFA case study demonstrates that the same cohort may yield differing findings when evaluated using randomisation or stratification approaches based on direct molecular measures in cell membranes.

Abnormalities of erythrocyte deformability and membrane lipid composition in alcoholic liver diseases

Abnormalities of erythrocyte deformability and membrane lipid composition in alcoholic liver diseases

Lack of effect of nifedipine on erythrocyte filterability and on erythrocyte membrane lipids in healthy volunteers: A double blind cross-over study

Lack of effect of nifedipine on erythrocyte filterability and on erythrocyte membrane lipids in healthy volunteers: A double blind cross-over study

Abnormalities of erythrocyte membrane lipids in insulin-dependent diabetics are improved by short term strict control of diabetes

Abnormalities of erythrocyte membrane lipids in insulin-dependent diabetics are improved by short term strict control of diabetes

Antihemolytic and antioxidant properties of pearl powder against 2,2′-azobis(2-amidinopropane) dihydrochloride-induced hemolysis and oxidative damage to erythrocyte membrane lipids and proteins

Pearl powder, a well-known traditional mineral medicine, is reported to be used for well-being and to treat several diseases from centuries in Taiwan and China. We investigated the in vitro antihemolytic and antioxidant properties of pearl powder that could protect erythrocytes against 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative damage to membrane proteins/lipids. Human erythrocytes were incubated with different concentrations of pearl powder (50–200 μg/mL) for 30 minutes and then exposed to AAPH for 2–6 hours. We found that AAPH alone time dependently increased the oxidative hemolysis of erythrocytes, while pearl powder pretreatment substantially inhibited the hemolysis in a concentration-/time-dependent manner. AAPH-induced oxidative damage to erythrocyte membrane lipids was evidenced by the elevated malondialdehyde (MDA) levels. However, pearl powder remarkably inhibited the malondialdehyde formation, and the 200 μg/mL concentration showed almost similar malondialdehyde values to the control. Furthermore, pearl powder suppressed the AAPH-induced high-molecular-weight protein formation and concomitantly increased the low-molecular-weight proteins in erythrocytes. Antioxidant potential that was measured as superoxide dismutase activity and glutathione content was significantly dropped by AAPH incubation, which suggests the vulnerability of erythrocytes to AAPH-induced oxidative stress. Noteworthy, erythrocytes pretreated with pearl powder showed restored superoxide dismutase activity and glutathione levels against AAPH-induced loss. Our findings conclude that pearl powder attenuate free radical-induced hemolysis and oxidative damage to erythrocyte membrane lipids/proteins. The potent antioxidant property of pearl powder may offer protection from free radical-related diseases.

Association between alcohol-induced erythrocyte membrane alterations and hemolysis in chronic alcoholics.

The present study aimed to understand the association between erythrocyte membrane alterations and hemolysis in chronic alcoholics. Study was conducted on human male volunteers aged between 35–45 years with a drinking history of 8–10 years. Results showed that plasma marker enzymes AST, ALT, ALP and γGT were increased in alcoholic subjects. Plasma and erythrocyte membrane lipid peroxidation, erythrocyte lysate nitric oxide (NOx) levels were also increased significantly in alcoholics. Furthermore, erythrocyte membrane protein carbonyls, total cholesterol, phospholipid and cholesterol/phospholipid (C/P) ratio were increased in alcoholics. SDS-PAGE analysis of erythrocyte membrane proteins revealed that increased density of band 3, protein 4.2, 4.9, actin and glycophorins, whereas glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and glycophorin A showed slight increase, however, decreased ankyrin with no change in spectrins (α and β) and protein 4.1 densities were observed in alcoholics. Moreover, alcoholics red blood cells showed altered morphology with decreased resistance to osmotic hemolysis. Increased hemolysis showed strong positive association with lipid peroxidation (r = 0.703, p<0.05), protein carbonyls (r = 0.754, p<0.05), lysate NOx (r = 0.654, p<0.05) and weak association with C/P ratio (r = 0.240, p<0.05). Bottom line, increased lipid and protein oxidation, altered membrane C/P ratio and membrane cytoskeletal protein profile might be responsible for the increased hemolysis in alcoholics.

Changes in the Fatty Acid Profile and Phospholipid Molecular Species Composition of Human Erythrocyte Membranes after Hybrid Palm and Extra Virgin Olive Oil Supplementation.

This work aims to evaluate and compare, for the first time, the effects of extra virgin olive oil (EVOO) and hybrid palm oil (HPO) supplementation on the fatty acid profile and phospholipid (PL) molecular species composition of human erythrocyte membranes. Results supported the effectiveness of both HPO and EVOO supplementation (3 months, 25 mL/day) in decreasing the lipophilic index of erythrocytes with no significant differences between HPO and EVOO groups at month 3. On the other hand, the novel and rapid ultraperformance liquid chromatography-tandem mass spectrometry method used for PL analysis reveals an increase in the levels of phosphatidylcholine and phosphatidylethanolamine species esterified with polyunsaturated fatty acids. This work demonstrates the ability of both EVOO and HPO to increase the degree of unsaturation of erythrocyte membrane lipids with an improvement in membrane fluidity that could be associated with a lower risk of developing cardiovascular diseases.

An Unrecognized Function of Cholesterol: Regulating the Mechanism Controlling Membrane Phospholipid Asymmetry.

An asymmetric distribution of phospholipids in the membrane bilayer is inseparable from physiological functions, including shape preservation and survival of erythrocytes, and by implication other cells. Aminophospholipids, notably phosphatidylserine (PS), are confined to the inner leaflet of the erythrocyte membrane lipid bilayer by the ATP-dependent flippase enzyme, ATP11C, counteracting the activity of an ATP-independent scramblase. Phospholipid scramblase 1 (PLSCR1), a single-transmembrane protein, was previously reported to possess scrambling activity in erythrocytes. However, its function was cast in doubt by the retention of scramblase activity in erythrocytes of knockout mice lacking this protein. We show that in the human erythrocyte PLSCR1 is the predominant scramblase and by reconstitution into liposomes that its activity resides in the transmembrane domain. At or below physiological intracellular calcium concentrations, total suppression of flippase activity nevertheless leaves the membrane asymmetry undisturbed. When liposomes or erythrocytes are depleted of cholesterol (a reversible process in the case of erythrocytes), PS quickly appears at the outer surface, implying that cholesterol acts in the cell as a powerful scramblase inhibitor. Thus, our results bring to light a previously unsuspected function of cholesterol in regulating phospholipid scrambling.

Erythrocyte Membrane Lipid Peroxidation in Recently Diagnosed Essential Hypertensive Patients : Correlation with Dyslipidemia

Erythrocyte Membrane Lipid Peroxidation in Recently Diagnosed Essential Hypertensive Patients : Correlation with Dyslipidemia

Inflammation-associated changes in lipid composition and the organization of the erythrocyte membrane

BackgroundReduced erythrocyte survival and deformability may contribute to the so-called anemia of inflammation observed in septic patients. Erythrocyte structure and function are affected by both the membrane lipid composition and the organization. We therefore aimed to determine whether these parameters are affected during systemic inflammation. MethodsA sensitive matrix-assisted laser desorption and ionization time-of-flight mass spectrometric method was used to investigate the effect of plasma components of 10 patients with septic shock and of 10 healthy volunteers subjected to experimental endotoxemia on erythrocyte membrane lipid composition. ResultsIncubation of erythrocytes from healthy control donors with plasma from patients with septic shock resulted in membrane phosphatidylcholine hydrolysis into lysophosphatidylcholine (LPC). Plasma from volunteers undergoing experimental human endotoxemia did not induce LPC formation. The secretory phospholipase A2 IIA concentration was enhanced up to 200-fold in plasma of septic patients and plasma from endotoxin-treated subjects, but did not correlate with the ability of these plasmas to generate LPC. Erythrocyte phosphatidylserine exposure increased up to two-fold during experimental endotoxemia. ConclusionsErythrocyte membrane lipid remodeling as reflected by LPC formation and/or PS exposure occurs during systemic inflammation in a secretory phospholipase A2 IIA-independent manner. General significanceSepsis-associated inflammation induces a lipid remodeling of the erythrocyte membrane that is likely to affect erythrocyte function and survival, and that is not fully mimicked by experimental endotoxemia.

The influence of erythrocyte maturity on ion transport and membrane lipid composition in the rat.

Significant relationships between ion transport and membrane lipid composition (cholesterol, total phospholipids and sphingomyelins) were found in erythrocytes of salt hypertensive Dahl rats. In these animals mean cellular hemoglobin content correlated negatively with Na(+)-K(+) pump activity and Na(+) leak but positively with Na(+)-K(+) cotransport activity. Immature erythrocytes exhibit lower mean cellular hemoglobin content (MCHC) than mature ones. The aim of the present study was to find a relationship between erythrocyte maturity, membrane lipid composition and ion transport activity in Wistar rats aged three months which were subjected to repeated hemorrhage (blood loss 2 ml/day for 6 days) to enrich circulating erythrocytes with immature forms. Immature and mature erythrocyte fractions in control and hemorrhaged rats were separated by repeated centrifugation. Hemorrhaged rats had increased number of reticulocytes but reduced hematocrit and MCHC compared to control rats. Immature erythrocytes of hemorrhaged rats differed from mature ones of control animals by elevated Na(+)-K(+) pump activity, reduced Na(+)-K(+) cotransport activity and increased Rb(+) leak. These ion transport changes in immature erythrocytes were accompanied by higher concentration of total phospholipids in their cell membranes. Membrane phospholipid content correlated positively with Na(+)-K(+) pump activity and cation leaks but negatively with Na(+)-K(+) cotransport activity. Moreover, they were also negatively related with MCHC which correlated negatively with Na(+)-K(+) pump activity and Rb(+) leak but positively with Na(+)-K(+) cotransport activity. Thus certain abnormalities of erythrocyte ion transport and membrane lipid composition detected in hypertensive animals might be caused by higher incidence of immature cells.

Short-Term Effects of Chlorpromazine on Oxidative Stress in Erythrocyte Functionality: Activation of Metabolism and Membrane Perturbation.

The purpose of this paper is to focus on the short-term effects of chlorpromazine on erythrocytes because it is reported that the drug, unstable in plasma but more stable in erythrocytes, interacts with erythrocyte membranes, membrane lipids, and hemoglobin. There is a rich literature about the side and therapeutic effects or complications due to chlorpromazine, but most of these studies explore the influence of long-term treatment. We think that evaluating the short-term effects of the drug may help to clarify the sequence of chlorpromazine molecular targets from which some long-term effects derive. Our results indicate that although the drug is primarily intercalated in the innermost side of the membrane, it does not influence band 3 anionic flux, lipid peroxidation, and protein carbonylation processes. On the other hand, it destabilizes and increases the autooxidation of haemoglobin, induces activation of caspase 3, and, markedly, influences the ATP and reduced glutathione levels, with subsequent exposure of phosphatidylserine at the erythrocyte surface. Overall our observations on the early stage of chlorpromazine influence on erythrocytes may contribute to better understanding of new and interesting characteristics of this compound improving knowledge of erythrocyte metabolism.

Increased membrane lipid peroxidation and decreased Na+/K+-ATPase activity in erythrocytes of patients with stable coronary artery disease.

We aimed to determine erythrocyte membrane lipid peroxidation levels and Na/K-ATPase activity in patients with and without coronary artery disease (CAD) documented by coronary angiography. A total of 144 patients who had undergone coronary angiography were divided into a CAD group (n=82) and a non-CAD group (control group, n=62) according to the results of coronary angiography. Lipid peroxide levels in plasma and the erythrocyte membrane were measured using a fluorimetric method. Total antioxidant status and Na/K-ATPase activity in plasma were determined using spectrophotometric methods. Lipid peroxidation levels were significantly higher in the erythrocyte membrane of CAD patients compared with controls, whereas Na/K-ATPase activity was significantly lower in the erythrocyte membrane of CAD patients compared with controls. The coronary artery scores were correlated positively with membrane lipid peroxidation (r=0.324, P<0.001) and negatively with Na/K-ATPase activity (r=-0.302, P<0.001). This study shows that the levels of membrane lipid peroxidation and Na/K-ATPase activity are correlated with the severity of CAD.

The Effects of Pistachio Consumption on Erythrocyte Membrane Lipids, Dietary Changes, and Satiety in Healthy College‐Aged Females

Research on pistachio consumption of erythrocyte membrane lipids, diet, and satiety is limited. Thus, we sought to investigate the effects of pistachio consumption on these outcomes in healthy females (n=48, age=21±0.51).We utilized a free‐living crossover design: two 10wk treatment periods; pistachios added (20% of kcals) (PT), a no‐pistachio control treatment, and a 15wk washout at both campuses. Measurements were taken at beginning and end of each treatment and nine randomized diet and satiety records (Visual Analog Scale) per treatment collected. Diet was analyzed using Nutrition Data System for Research software. Data were analyzed by mixed effects model.Neither treatment had significant effects on erythrocyte membrane lipids; however, the PT membranes contained more PUFA, total EFAs, as well as EPA and DHA. Dietary relationship trends for membrane incorporation indicate dietary pistachio MUFA and PUFA positively influence membrane lipids. PT diet data indicated a significant (P&lt;0.001) increase of dietary total MUFA, total PUFA, insoluble fiber, gamma‐tocopherol, vitamin B6, copper, potassium, and decreased glycemic index. PT satiety data significantly indicated that when pistachios are consumed there was less hunger, participants were more satisfied, and felt more full when they consume pistachios than when they did not consume pistachios.Inclusion of 20% of kcals as pistachios in the diet may potentially increase lipid erythrocyte membrane concentrations, improve dietary nutrient intake, increase satiety, and decrease hunger and cravings.

Microviscosity of erythrocyte membranes during chronic heart failure in patients of middle and senior age groups

Microviscosity coefficients were studied in the area of integrated and annular lipids of erythrocyte membranes in the peripheral blood of patients aged 35–50 and 60–75 with chronic coronary heart disease (CHD), as well as healthy donors of corresponding age. It was found in healthy donors that the microviscosity coefficients in the area of integrated and of annular lipids are significantly higher in the senior age group (60–75 years). In CHD, both an increase and a decrease in the microviscosity parameters in the area of lipid–lipid interactions can be characteristic for erythrocyte membranes, regardless of the patient age. In the protein–lipid contacts, an increase in microviscosity parameters is characteristic for patients aged 35–50 and, in contrast, a decrease in the microviscosity coefficient was observed in 60- to 75-year-old patients. It was concluded that the indicators of erythrocyte membrane microviscosity in patients of different age groups reflect both the implementation of general mechanisms of adaptive changes in cell membranes and the individual characteristics determined by their lipid and protein composition during the development of chronic CHD.

Effect of hydrosoluble vitamin E on erythrocyte membrane lipid composition in patients with advanced cirrhosis: An open‐label pilot trial

Deficiency in vitamin E, a natural antioxidant, participates in abnormal erythrocyte membrane lipids, structural alterations and hemolysis in advanced cirrhosis. Poor absorption of fat-soluble vitamins limits full correction of deficiency with standard formulations in cirrhosis with cholestasis. The aim of the present study was to examine safety and effects of tocofersolan, a water-soluble derivative of vitamin E, on erythrocyte membrane lipids and anemia in patients with biopsy-proven advanced cirrhosis, vitamin E deficiency and hemolysis. Twenty patients (age, 53 ± 10 years; Child class B/C, 8/12), with low plasma vitamin E, chronic anemia and hemolysis, received oral tocofersolan 700 mg/day for 4 weeks. Erythrocyte membrane lipid composition (cholesterol [Chol], phospholipids [Phosph]) was determined by enzymatic assays. Total and conjugated bilirubin, hemoglobin and vitamin E were measured. Abdominal pain occurred in one patient. Five patients received blood transfusions due to severe anemia. After 4 weeks, both Chol and Phosph decreased, but changes were not significant. Both plasma vitamin E (P < 0.05) and hemoglobin (P < 0.05) increased, together with a decrease in total (P < 0.05) and conjugated (P < 0.05) bilirubin. In patients with advanced cirrhosis, low vitamin E plasma levels and chronic anemia with hemolysis, oral tocofersolan was overall well tolerated, but did not affect erythrocyte membrane lipid composition.

Erythrocyte membrane cholesterol and lipid core growth in a rabbit model of atherosclerosis: modulatory effects of rosuvastatin

Abstract Background Lipid core expansion is partly responsible for the conversion of a stable atherosclerotic lesion to a rupture-prone plaque. Intraplaque hemorrhage contributes to the accumulation of cholesterol within unstable plaques. In the present study, we investigated, using a rabbit model of atherosclerosis, the extent to which diet-induced increases in cholesterol content of erythrocyte membranes (CEM) contribute to lipid core expansion and the modulatory effect of rosuvastatin use. Methods and results Rabbits fed with atherogenic diet (0.75% cholesterol) for 5months exhibited advanced atherosclerotic lesions (mean plaque area, 0.39±0.03mm 2 ), and lipid core size was associated with the concentration–time integral (CTI) of CEM levels ( r =0.567, P =0.004) independent of other established predictors of lipid core size. Further experiments were performed by feeding rabbits atherogenic diet (1% cholesterol) for 3months, followed by either normal diet or normal diet plus rosuvastatin for the next 3months. Although no differences were observed in total plaque area between both groups, administration of rosuvastatin was associated with significantly smaller lipid cores, fewer macrophages within the lipid core, less microvessels as well as with lower CTI of CEM levels compared to normal diet alone. Moreover, intraplaque erythrocyte membranes covered a smaller lipid core area in rabbits under rosuvastatin plus normal diet as opposed to rabbits under diet alone. Conclusions Increased CEM levels, induced by high-cholesterol diet, are associated with lipid core growth. Ingestion of a potent HMG-CoA reductase inhibitor (rosuvastatin) may decrease CEM levels, and this effect may contribute to regression of the lipid core.

Purification of Pomegranate Pericarps (&lt;i&gt;Punica granatum l.&lt;/i&gt;) Extracts with Macroporous Resins and Evaluation of Antioxidant Activities &lt;i&gt;In Vivo&lt;/i&gt;

Punica granatum L. Pomegranate has been traditionally used as a folk fruits for centuries in Oriental countries. It extract and subsequent fractions were used to evaluate antioxidant and related activities of Punica granatum L. It were extracted by 70% acetone, and then purified by HPD-400 macroporous adsorbent resins column. The aim of this study was to verify the antioxidant properties of acetone extracts of pomegranate pericarps and their lyophilized samples, and also to study the relationship between the activity and the contents of the tannins. The effects of natural extracts on microsomal lipid of mice liver and erythrocyte membrane lipid were examined. Vc/Fe2+, Cys/Fe2+induced microsomal lipid peroxidation, UV light induced erythrocyte membrane lipid peroxidation were measured by malondialdehyde (MDA) content with spectrophotometric methods. The natural plant extracts not only diminish the Vc/Fe2+,Cys/Fe2+ induced microsomal lipid peroxidation, UV light induced erythrocyte membrane lipid peroxidation and also showed its activity in a concentration-dependent manner. Our study found that the higher tannins contents showed more effective of antioxidant properties. Keywords: Punica granatum L.; liver microsome; antioxidant activity; Lipid peroxidation