Osmotic Fragility Of Human Erythrocytes Research Articles

Action of cetiedil citrate on the cation content, deformability, and osmotic fragility of human erythrocytes

Action of cetiedil citrate on the cation content, deformability, and osmotic fragility of human erythrocytes

Особенности модификации геометрических параметров и изменения осмотической хрупкости эритроцитов человека под влиянием сахарозы и ПЭГ-1500

The effect of be polyethylene glycol with a molecular weight of 1500 (PEG-1500) and sucrose on the changes in geometric parameters and osmotic fragility of human erythrocytes was studied. At equal mass fractions of two substances, sucrose caused more pronounced changes in the distribution of erythrocytes according to direct light scattering (FSC) in comparison with PEG. Nevertheless, PEG induced a shift in the distribution of erythrocytes according to the sphericity index in the direction of the spherical cell types, and also increased the osmotic fragility of the erythrocytes relative to the intact and incubated in the presence of sucrose cells. Stomatocytosis was the prevailing trend of the shape modification in the PEG presence, while the effect of sucrose led to the dominance of dehydrated flattened cells. Differences in the external manifestations of the erythrocyte response to PEG and sucrose solutions, accompanied by unequal changes in osmotic fragility, indicate the role of structural membrane modifications induced by cryoprotectants for cell stabilization during subsequent freezing. Probl Cryobiol Cryomed 2017; 27(4): 2 96 – 310

Safety assessment and antioxidant activity of Lantana montevidensis leaves: Contribution to its phytochemical and pharmacological activity.

Lantana camara, the widely studied species, and L. montevidensis, the less studied species of the genus Lantana are both used in traditional medicine for the same purpose (anti-asthma, anti-ulcer, anti-tumor, etc). However, little is known about the toxicity of L. montevidensis and there is limited information on its chemical constituents. Here, we investigated for the first time the genotoxicity and cytotoxicity of the ethanolic (EtOH) and aqueous extracts from the leaves of Lantana montevidensis in human leukocytes, as well as their possible interaction with human erythrocyte membranes in vitro. The antioxidant activities of both extracts were also investigated in chemical and biological models. Treatment of leukocytes with EtOH or aqueous extracts (1-480 µg/mL) did not affect DNA damage index, but promoted cytotoxicity at higher concentrations (240-480 µg/mL). Both extracts did not modify the osmotic fragility of human erythrocytes. The extracts scavenged DPPH radical and prevented Fe2+-induced lipid peroxidation in rat's brain and liver homogenates, and this was likely not attributed to Fe (II) chelation. The HPLC analysis of the extracts showed different amounts of polyphenolic compounds (isoquercitrin, gallic acid, catechin, ellagic acid, apigenin, kaempferol, caffeic acid, rutin, quercitrin, quercetin, chlorogenic acid, luteolin) that may have contributed to these effects. These results supported information on the functional use of L. montevidensis in folk medicine.

Ebselen exhibits glycation‐inhibiting properties and protects against osmotic fragility of human erythrocytes in vitro

Diabetic status is associated with an increase on oxidative stress markers in humans and animal models. We have investigated the in vitro effects of high concentrations of glucose on the profile of oxidative stress and osmotic fragility of blood from control and diabetic patients; we considered whether its antioxidant properties could afford some protection against glucose-induced osmotic fragility, and whether ebselen could act as an inhibitor of hemoglobin glycation. Raising blood glucose to 5-100 mmol/L resulted in a concentration-dependent increase of glycated hemoglobin (HbA1c; P < 0.001) and thiobarbituric acid reactive species (TBA-RS) content (P < 0.004). Non-protein SH groups (NPSH) also increased significantly as the concentration of glucose increased up to 30 mmol/L (P < 0.001). The osmotic fragility was more pronounced in blood of uncontrolled diabetic patients than in these non-diabetic subjects. Ebselen significantly reduced the glucose-induced increase in osmotic fragility and inhibited HbA1c formation (P < 0.0001). These results indicate that blood from patients with uncontrolled diabetes are more sensitive to osmotic shock than from patients with controlled diabetes and control subjects in relation to increased production of free radicals in vivo.

Osmotic fragility of human erythrocytes in vitro using Vipera lebetina venom

The objective of this study was to investigate the in vitro effect of Vipera lebetina venom on human erythrocytes’ osmotic fragility with respect to different venom concentrations, time of incubation with the venom, initial volume of red blood cells, and presence of antivenom. In vitro osmotic fragility of human erythrocytes was determined using Dacie and Lewis method. Osmotic fragility is increased significantly after incubation with the venom at different concentrations. The maximal effect was detected at the venom concentration of 400 μg. Time of incubation with the venom was an important factor in hemolytic process while the initial cell volume has no significant effect. Incubation of envenomed erythrocytes for 120 min with antivenom did not reverse the changes in osmotic fragility induced by the venom. The study suggests that the venom could alter the susceptibility of erythrocytes to hemolysis when subjected to osmotic stress and the degree of hemolysis depends on venom concentration and time of intubation with the venom.

Structure-activity relationships regarding the antioxidant effects of the flavonoids on human erythrocytes

The effects of eleven flavonoids on lipid peroxidation, protein degradation, deformability and osmotic fragility of human erythrocytes exposed in vitro to 10 mM H2O2 for 60 min at 37˚C have been studied. The following flavonoids; quercetin, rutin and morin significantly protected erythrocytes against lipid peroxidation caused by H2O2. This inhibition of lipid peroxidation could be explained by the presence of at least two hydroxyl groups in ring B of the flavonoid structure, regardless of their positions. However, the flavonoids; quercetin, 3,5,7-trihydroxy-4'-methoxy flavone-7-rutinoside and 3-hydroxy flavone significantly protected erythrocytes against protein degradation. This inhibition could also be explained by the presence of a hydroxyl group at C-3 in ring C of the flavonoid structure. Quercetin and 3,5,7-trihydroxy-4'-methoxy flavone-7-rutinoside significantly protected erythrocytes against loss of deformability and increased osmotic fragility, indicating that the loss of erythrocyte deformability and the increase in osmotic fragility of erythrocytes exposed to H2O2 are related to protein degradation rather than to lipid peroxidation. The other flavonoids (chrysin, 2-carboxy ethyl dihydroxy flavone, apigenin, cirsimaritin, α-naphto flavone and flavanone) failed to protect erythrocytes against the observed oxidative damages. The results demonstrate the importance of the chemical groups substituted on the basic skeleton of the flavonoids in dictating the type of antioxidant activity, and also demonstrate the hemorheological potentials of flavonoids that have particular protein-antioxidant activities.

تأثير خلاصة سبع نباتات تقليدية شائعة الاستعمال على كريات الدم الحمراء

Background: Many plants contain chemical substances that might have a hemolytic or anti-hemolytic effect on human erythrocytes. Aim: To test the influence of the aqueous extract of seven commonly used plants in Jordan on the osmotic fragility of human erythrocytes. Methods: Osmotic fragility test was used to assess hemolytic activity of the crude extracts of the plants. The dried plants were extracted and dissolved in dimethyl sulphoxide. Blood samples were collected from healthy volunteers, dissolved and then divided into control and treated groups. The results of hemolysis were determined spectrophotometrically. Data were analyzed using SPSS 15. Results: The plants were classified into three groups: group I: has no effect and includes Solanum tuberosum, Solanum melongena, Hibiscus sabdariffa, and Malva sylvestris, group II: decreases hemolysis and includes Colchicum ritchii, and group III: increases hemolysis and includes Ferula harmonis, and Silybum marianum. Results from group II and III showed that hemolysis was independent of time, while the degree of hemolysis was concentration- dependent. Conclusion: Some plants have anti hemolytic effect on human erythrocytes; others induce it, and a third group does not have any effect. خلفية: تحتوي العديد من النباتات مواد كيميائية قد يكون لها تأثير انحلالي أو مضاد للانحلال على كريات الدم الحمراء. الهدف: اختبار تأثير المستخلص المائي لسبع نباتات تستخدم عادة في الأردن على مدى تحلل كريات الدم الحمراء. طريقة العمل :تم استخدم اختبار هشاشة كريات الدم الحمراء لتقييم النشاط الانحلالي أو مضاد الانحلال الذي تحدثه مستخلصات النباتات. تم تجفيف النباتات واستخلاصها ثم إذابتها في DMSO. تم جمع عينات دم من متطوعين أصحاء ، ثم تقسيم العينات إلى مجموعة المراقبة ومجموعة المعالجة. نتائج انحلال الدم تم قياسها بواسطة تحليل الطيف الضوئي. تم تحليل البيانات باستخدام البرنامج الاحصائي SPSS 15. النتائج : تم تقسيم النباتات الى ثلاث مجموعات بناء على النتائج: المجموعة الأولى: ليس لها أي تأثير على انحلال كريات الدم الحمراء وتشمل: Solanum tuberosum, Solanum melongena, Hibiscus sabdariffa, Malva sylvestris، المجموعـة الثانيـة: تقلـل مـن الانحلال فـي كريـات الـدم الحمـراء وتشمـل Colchicum ritchii والمجموعة الثالثة : تؤدي الى زيادة انحلال كريات الدم الحمراء وتشمل ferula Harmonis ، Silybum marianum. اظهرت النتائج من المجموعة الثانية والثالثة ان انحلال كريات الدم الحمراء حصل بغض النظر عن الزمن ، في حين أن درجة انحلال كريات الدم الحمراء كانت تعتمد على التركيز. الاستنتاج: بعض النباتات لها تأثير مضاد لانحلال كريات الدم الحمراء في الإنسان، وبعضها الآخر يسبب انحلالا في كريات الدم الحمراء، ومجموعة ثالثة ليس لها تأثير على كريات الدم الحمراء.

The approximate entropy of the electromyographic signals of tremor correlates with the osmotic fragility of human erythrocytes.

BackgroundThe main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics.MethodsThis work sought correlations between the osmotic fragility of erythrocytes and features extracted from electromyographic (EMG) activity resulting from physiological tremor in healthy patients (N = 44) at different ages (24-87 years). The osmotic fragility was spectrophotometrically evaluated by the dependence of hemolysis, provided by the absorbance in 540 nm (A54o), on the concentration of NaCl. The data were adjusted to curves of sigmoidal regression and characterized by the half transition point (H50), amplitude of lysis transition (dx) and values of A540 in the curve regions that characterize the presence of lysed (A1) and preserved erythrocytes (A2). The approximate entropy was estimated from EMG signals detected from the extensor carpi ulnaris muscle during the movement of the hand of subjects holding up a laser pen towards an Archimedes spiral, fixed in a whiteboard. The evaluations were carried out with the laser pen at rest, at the center of the spiral, and in movement from the center to the outside and from outside to the center. The correlations among the parameters of osmotic fragility, tremor and age were tested.ResultsNegative correlations with age were found for A1 and dx. With the hand at rest, a positive correlation with H50 was found for the approximate entropy. Negative correlations with H50 were found for the entropy with the hand in movement, as from the center to the outside or from the outside to the center of the spiral.ConclusionIn healthy individuals, the increase in the erythrocyte osmotic fragility was associated with a decrease in the approximate entropy for rest tremor and with an increase of the entropy for movement tremor. This suggests that the neuromuscular degeneration associated with tremor entails also the mechanisms involved in the breakdown of structural homeostasis of the erythrocyte membrane.

Effects of charged amphiphiles in depolarising solutions on potassium efflux and the osmotic fragility of human erythrocytes

The effect of the presence of charged amphiphiles during the incubation of human erythrocytes in a sucrose-substituted low-Cl − solution on the shift of the osmotic resistance profile and the net K + efflux was investigated. Osmotic fragility was determined by fitting the complementary error function to the haemolysis resistance curve. K + efflux was calculated from the increase in the K + concentration in supernatant measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). The cationic amphiphile hexadecyltrimethylammonium bromide (CTAB) at 14 μM decreases, whereas the anionic amphiphile sodium dodecyl sulfate (SDS) at 50 μM increases the shift of the haemolysis resistance curve of erythrocytes incubated in isotonic sucrose by 0.069 and 0.079 %NaCl, respectively. Both the positively and the negatively charged amphiphile caused a significant change in the K + efflux into isotonic sucrose solution: CTAB decreased and SDS increased K + efflux by about 40%. In view of the lack of effect of the investigated compounds on the haemolysis resistance curve and K + efflux from human erythrocytes incubated in isotonic NaCl solution, these results suggest that the insertion of charged amphiphiles into the erythrocyte membrane modulates the properties of the K + transport pathway which is activated under low ionic strength (LIS) conditions.

Oxidative stress of vanadium-mediated oxygen free radical generation stimulated by aluminium on human erythrocytes.

It has been suggested that aluminium stimulates vanadium-mediated superoxide radical generation. The oxidative stress of generated superoxide radicals on antioxidant enzyme activity, oxidation of NADH and NADPH, membrane lipid peroxidation and osmotic fragility in human red blood cells (RBC) was investigated. RBC were incubated with varying concentrations of vanadium and aluminium ions at 37 degrees C for 2 h. RBC incubated with vanadium ions showed significantly increased superoxide dismutase and catalase activities, and oxidized NADH and NADPH concentrations compared with control RBC preparations. Erythrocyte lipid peroxidation was assessed by measuring thiobarbituric acid reactivity. RBC incubated with elevated levels of vanadium showed significantly increased membrane lipid peroxidation when compared with control RBC; it increased further on addition of aluminium. A significant positive correlation was observed between the extent of vanadium induced membrane lipid peroxidation and the osmotic fragility of treated RBC. In the presence of vanadium, aluminium stimulates superoxide dismutase and catalase activities. NADH and NADPH oxidation and membrane lipid peroxidation, as well as increasing osmotic fragility of human erythrocytes. The stimulatory effect of aluminium was dependent on concentration. These results may have implications for the mechanism of toxicity of aluminium and vanadium in haemodialysis patients.

The decrease in osmotic fragility of erythrocytes during supplementation with n-3 fatty acids is a transient phenomenon

In order to study the effect of dietary n-3 fatty acids on osmotic fragility of human erythrocytes, 11 healthy subjects were given a supplement of 6 g day-1 of an oil containing 50% n-3 fatty acids for either 14 days or 34 days. Fourteen days after start the osmotic fragility was decreased by 60-80% (buffer-salt concentration 0.41%), and the level of n-3 fatty acids in membrane phospholipids was increased by approximately 60%. The decrease in fragility was less marked after 24 days and almost at the pre-supplementation level after 34 days. There was no correlation between changes in fragility and in the fatty acid pattern of membrane phospholipids of the erythrocytes. The changes induced in fatty acid composition of phospholipids did not affect membrane fluidity. It is concluded that factors other than the nature of fatty acids in membranes may be involved in modifying osmotic fragility, and that there is no correlation between membrane fragility and membrane fluidity.

The relationship between the osmotic fragility of human erythrocytes and cell age

Erythrocytes in a normal blood sample are hemolyzed over a range of hypotonic salt concentrations. In order to investigate the relationship between the distribution of osmotic fragilities and the distribution of cellular ages, the osmotic fragility has been compared with three indices of cellular age. The activity of glutamic-oxalacetic transaminase (GOT) and the percentage hemoglobin A 1C were measured in samples hemolyzed in different hypotonic salt concentrations. The osmotic fragility curve was also obtained for cells of different density separated by centrifugation. These experiments indicate that the fragility distribution is not an accurate reflection of the distribution of cellular ages. The mean fragility for older cells is higher than that of younger cells. However, cellular aging does not produce a gradual increase in osmotic fragility. Instead, it seems to produce changes which can both increase and decrease the fragility, resulting in a broader distribution of fragilities with some of the older cells actually less fragile than the younger ones.

Effect of lead in vitro on water metabolism and osmotic fragility of human erythrocytes.

The addition of lead to normal human blood was previously found to cause a decrease in erythrocyte osmotic fragility in vitro. The mechanism of the decreased osmotic fragility caused by lead has not been completely clarified, but the following hypothesis has been proposed. Lead causes a leakage of water from erythrocytes, thus more water can enter the cell before haemolysis occurs. There has been no report, however, of the direct measurement of the intracellular water content of erythrocytes treated with lead. This study has tried to clarify the relation between intracellular water and the osmotic fragility of lead-treated erythrocytes in vitro. The results showed that 0.05 microM/ml of lead decreased the osmotic fragility, the intracellular water content, and intracellular potassium and mean corpuscular volume, increased the plasma water content and trapped water content, and contracted the erythrocyte shape. These changes corresponded well with each other, and close coincidence of the osmotic fragility and the intracellular water content was also observed.

Effect of parathyroid hormone on osmotic fragility of human erythrocytes.

The survival of erythrocytes (RBC) is shortened in uremia, and it has been shown that calcium influx into RBC evoked crenation and increased their rigidity. The high blood levels of parathyroid hormone (PTH) may augment entry of calcium into RBC and hence affect their integrity. We examined the effect of PTH on osmotic fragility of human RBC and investigated the mechanisms through which PTH interacts with RBC. Both the amino-terminal (1-34) PTH and the intact (1-84) PTH, but not the carboxy-terminal (53-84) PTH, produced significant increases in osmotic fragility. This effect was abolished by prior inactivation of the hormone. There was a dose-response relationship between both moieties of PTH and the increase in osmotic fragility. This action of PTH required calcium, was mimicked by calcium ionophore, and was partially blocked by verapamil. PTH caused significant influx of (45)Ca into RBC, which was not associated with potassium leak. The hormone did not affect water content of RBC. Scanning electron microscopy revealed that the incubation of RBC with PTH was associated with the appearance of membrane filamentous extensions, which anchor RBC together. Inhibition of glycolytic activity of RBC with NaF or inhibition of Na-K-activated ATPase with ouabain did not abolish the effect of PTH on osmotic fragility. PTH did not stimulate RBC Na-K-activated ATPase or Mg-dependent ATPase but caused marked and significant stimulation of Ca-activated ATPase. The basal activity of the RBC adenylate cyclase was low and PTH produced only a modest stimulation of this enzyme. Both cyclic AMP and dibutyryl cyclic AMP had no effect on osmotic fragility. THE DATA INDICATE THAT: (a) the RBC is a target organ for PTH, (b) the hormone increases osmotic fragility of RBC, and (c) this effect of PTH is due to enhanced calcium entry into RBC. We suggest that the increased calcium influx may affect the spectrin-actin of the cytoskeletal network of the RBC and may alter the stability and integrity of the cell membrane. This action of PTH on the RBC could be, at least in part, responsible for the shortened survival of RBC in uremia, and assign a new role for PTH in the pathogenesis of the anemia of uremia.

Diminished osmotic fragility of human erythrocytes following the membrane insertion of oxygenated sterol compounds

Oxygenated sterol compounds (OSC), when incubated for 1 hr with human erythrocytes in lipoprotein-depleted medium at concentrations of 0.625-5 X 10(-5) M, are inserted into the cell membrane and remain there despite subsequent washing of the cells. The insertion results in expansion of the surface area of the red cell ghost membrane, an increase in critical hemolytic volume, and as a consequence, in diminished osmotic fragility of the erythrocytes. This effect is seen with echinocyte-forming as well as with non-echinocyte-forming OSC. Erythrocytes treated with OSC do not differ from control cells with respect to their mean cell volume (MCV) in isotonic solution, water content, ion fluxes, and filterability through polycarbonate filters. The shift of the osmotic fragility curve toward lower NaCl concentrations is proportional to the amount of OSC inserted into the red cell membrane. 7 beta-Hydroxycholesterol, 22-ketocholesterol, and 20 alpha-hydroxycholesterol are the most potent inhibitors of osmotic lysis. The effect of OSC on osmotic fragility is diminished if the erythrocytes are incubated in a lipoprotein-containing medium; free cholesterol, however, does not change this effect. Various progesterones also protect red cell from osmotic lysis, but only if the erythrocytes are directly exposed to the compounds present in the hypotonic NaCl solutions used for measurement of their osmotic fragility. Progesterones do not remain in the membrane after the cells have been washed. The OSC are also capable of correcting the osmotic fragility curve of red cells from patients with hereditary spherocytosis. These experiments may suggest an approach to the pharmacologic treatment of hereditary spherocytosis.

Diminished Osmotic Fragility of Human Erythrocytes Following the Membrane Insertion of Oxygenated Sterol Compounds

Abstract Oxygenated sterol compounds (OSC), when incubated for 1 hr with human erythrocytes in lipoprotein-depleted medium at concentrations of 0.625- 5 X 10(-5) M, are inserted into the cell membrane and remain there despite subsequent washing of the cells. The insertion results in expansion of the surface area of the red cell ghost membrane, an increase in critical hemolytic volume, and as a consequence, in diminished osmotic fragility of the erythrocytes. This effect is seen with echinocyte-forming as well as with non-echinocyte-forming OSC. Erythrocytes treated with OSC do not differ from control cells with respect to their mean cell volume (MCV) in isotonic solution, water content, ion fluxes, and filterability through polycarbonate filters. The shift of the osmotic fragility curve toward lower NaCl concentrations is proportional to the amount of OSC inserted into the red cell membrane. 7 beta-Hydroxycholesterol, 22-ketocholesterol, and 20 alpha-hydroxycholesterol are the most potent inhibitors of osmotic lysis. The effect of OSC on osmotic fragility is diminished if the erythrocytes are incubated in a lipoprotein-containing medium; free cholesterol, however, does not change this effect. Various progesterones also protect red cell from osmotic lysis, but only if the erythrocytes are directly exposed to the compounds present in the hypotonic NaCl solutions used for measurement of their osmotic fragility. Progesterones do not remain in the membrane after the cells have been washed. The OSC are also capable of correcting the osmotic fragility curve of red cells from patients with hereditary spherocytosis. These experiments may suggest an approach to the pharmacologic treatment of hereditary spherocytosis.

The erythrocyte membrane site for the effect of temperature on osmotic fragility

The osmotic fragility of human erythrocytes is well known to decrease as the temperature is elevated. The cellular site for the temperature effect was studied by assessing possibles roles of hemoglobin and of membrane lipids and by taking advantage of the unique response of camel erythrocytes to temperature. It is concluded that the erythrocyte membrane is the site for the temperature effect on osmotic fragility. The human erythrocyte is likely to rupture in protein-lipid boundary regions in the membrane, from which cholesterol is apparently excluded.

Erythrocyte osmotic fragility in the presence of lead or mercury.

SummaryThe osmotic fragility of human erythrocytes was analyzed with a recording Fragilograph after incubation with known amounts of lead or mercury. Incubation with lead produced two populations of red cells, one osmotically fragile and the other osmotically resistant. Mercury (10-4 to 10-6M Hg), unlike lead, caused an overall increase in osmotic fragility. With lead an osmotically resistant population of erythrocytes developed after 1 hr incubation with 0.7 to 1.0 × 10-4M Pb (1500 to 2000 μg Pb/100 ml), after 2 hr with 0.3 × 10-4 M Pb (800 μg Pb/100 ml), but did not appear until 24 hr incubation with 10-5M Pb (200 μg Pb/100 ml). The gradual development of an osmotically resistant population of erythrocytes with lead, but not with mercury, indicates different modes of interaction of these two ions with the red cell membrane and contents.

Effects of cytochalasin B on osmotic fragility and deformability of human erythrocytes.

The presence of cytochalasin B is associated with an increase in the osmotic fragility of human erythrocytes as determined by measuring the extent of hemolysis in solutions of various osmolarities. Erythrocytes exposed to cytochalasin and subsequently washed displayed the same osmotic fragility as controls. Cytochalasin similarly increased deformability as indicated by measurement of pressure differences required to draw single cells into a micropipette of 2.0–2.5 μm diameter. The required pressure, reduced in the presence of cytochalasin, was the same as for controls after the cells treated with cytochalasin were washed.The reversible increases in osmotic fragility and deformability are interpreted as indicative of a reduction in tensile strength of the plasma membrane, perhaps associated with a loss of microfilaments.