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BACKGROUND: Hemorheologic indices are known to be related to vascular complications in variable clinical settings. However, little is known about the associations between hemorheologic parameters and acute myocardial infarction (AMI) in type 2 diabetes mellitus (T2DM). The purpose of this study was to demonstrate the changes of hemorheologic environment inside of blood using hemorheologic parameters, especially the elongation index (EI) and critical shear stress (CSS) in diabetics with versus without AMI. METHODS: A total of 195 patients with T2DM were enrolled. Patients were divided into the study group with AMI (AMI+, n = 77) and control group (AMI−, n = 118) who had no history of coronary artery disease. Hemorheologic parameters such as EI and CSS were measured and compared between the two groups. RESULTS: The EI was lower (30.44%±1.77% in AMI+ and 31.47%±1.48% in AMI−, P < 0.001) but the level of CSS was higher (316.13±108.20 mPa in AMI+ and 286.80±85.34 mPa in AMI−, P = 0.040) in the AMI+. The CSS was significantly related to the erythrocyte sedimentation rate (R² = 0.497, P < 0.001) and use of dipeptidyl peptidase-4 inhibitors (R² = 0.574, P = 0.048). CONCLUSION: Diabetics with AMI resulted in adverse hemorheologic changes with lower EI and higher CSS compared to diabetic subjects without AMI. Evaluation of the hemorheologic parameters may provide valuable supplementary information for managing patients with AMI and T2DM.
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Humans , Blood Sedimentation , Coronary Artery Disease , Diabetes Mellitus, Type 2 , Erythrocyte Deformability , Hemorheology , Myocardial InfarctionABSTRACT
AIM:To investigate the effects of hypoxia exposure on the structure and function of erythrocytes in rats at different time.METHODS:Male SD rats(n=40)were randomly divided into 5 groups,normal control group,1-week hypoxia group ,2-week hypoxia group ,3-week hypoxia group and 4-week hypoxia group ,with 8 rats per group.The rats in hypoxia groups were placed in the simulated 5800 m of high altitude in a hypobaric chamber for different time.The values of detected blood ,erythrocyte deformation index ,erythrocyte osmotic fragility ,erythrocyte oxygen dissociation ,e-rythrocyte apoptosis and bone marrow biopsy were determined.RESULTS:Compared with normal control group ,the red blood cell count ,hemoglobin content ,mean corpuscular volume and mean corpuscular hemoglobin significantly increased(P<0.01).Eversion rate of phosphatidylserine of erythrocytes increased.Oxygen half-saturation of hemoglobin increased(P<0.05).Bone marrow erythroid proliferation increased.The erythrocyte deformation index and erythrocyte osmotic fra-gility decreased significantly(P<0.01).In addition,oxygen dissociation curves shifted to the right.CONCLUSION:In the early stage of hypoxia ,compared with normal control group ,the changes of erythrocyte structure and function increase the oxygen supply to the tissue and are conducive to adapting to the plateau.However ,with the extension of hypoxia ,ex-cessive erythrocytosis results in thrombosis ,microcirculation disturbance and aggravating tissue hypoxia.
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Aims: Loss of erythrocyte deformability under oxidative stress is poorly understood. The present study aimed to determine which of the detrimental effects of oxidant stress, namely, lipid peroxidation or protein degradation, is responsible for loss of erythrocyte deformability. Methodology: Different natural and synthetic antioxidants were tested for their protective effects on erythrocyte deformability, lipid peroxidation and protein degradation after exposure to H2O2. Antioxidants used included -Tocopherol (vitamin E), Butylated Hydroxytoluene (BHT), vitamin C, PNU-101033E, carbon monoxide (CO) and selected flavonoids and herbal extracts. Results: Exposure of human erythrocytes in vitro to H2O2 caused loss of deformability, lipid peroxidation and protein degradation. Pre-incubation of erythrocytes with vitamin E, BHT, vitamin C, PNU-101033E, the flavonoids rutin and morin and herbal extracts of Ferula hermonis, Hibiscus sabdariffa, Teucrium polium, prevented lipid peroxidation caused by H2O2 but did not prevent loss of erythrocyte deformability, nor protein degradation. CO, the flavonoid quercetin and herbal extracts of Nigella sativa and Allium sativum prevented both lipid peroxidation and protein degradation, but also prevented loss of erythrocyte deformability. The flavonoid 3,5,7-trihydroxy-4’-methoxy flavone-7-rutinoside prevented both protein degradation and loss of deformability, with no effect on lipid peroxidation. Vitamin C, unexpectedly, caused a significant increase in loss of erythrocyte deformability induced by H2O2 in parallel to the increased rate of protein degradation. Conclusion: These results suggest that protein degradation rather than lipid peroxidation is responsible for loss of erythrocyte deformability under oxidative stress. Also that lipid peroxidation and protein degradation occur by independent mechanisms. This study should initiate a search for potential drugs that can prevent protein oxidation as well as lipid peroxidation, thereby acting in the prevention of adverse hemorheological consequences in disease states associated with oxidative stress. Caution should be exercised in the therapeutic use of vitamin C, especially under oxidant stress.
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Aim: It is known that blood viscosity and erythrocyte aggregation are increased and erythrocyte deformability is decreased in diabetic patients. Blood rheology is known to be affected by numerous factor including anaesthetic drugs. Accordingly, we aimed to investigate the effects of sevoflurane and desflurane on erythrocyte deformability in diabetic rats. Place and Duration of Study: The study was performed upon the approval of Gazi University Experimental Animals Ethics Committee in Gazi University Experimental and Clinical Research Center (GUDAM). Methodology: In this study, 24 male albino Wistar rats were used.Diabetes was induced by a single IP injection of streptozotocin, at a dose of 55 mg.kg-1 body weight in 18 Wistar Albino rats.72 hours following this injection rats were classified as diabetic if their fasting blood glucose (FBG) levels exceeded 250 mg.dl-1 and only animals with FBGs of > 250 mg.dl-1 were included in the diabetic groups. After the effects of chronic diabetes encountered diabetic rats were randomly assigned into diabetic control (group DC), diabetic desflurane (group DD) and diabetic sevoflurane (group DS) groups. Another 6 rats without diabetes were assigned as control group (group C). 4 weeks after the injection of streptozotocin diabetic rats were anaesthetized by desflurane 6% or sevoflurane 2% at a dose by which minimal alveolar concentration (MAC) for rats would be one. The drugs were given for 2 hours within 100% oxygen at a rate of 4 L.min1. After the anesthesia all rats were given ketamine (100 mg.kg-1) intraperitoneally and blood samples were withdrawn from the abdominal aorta and then rats were sacrificed. Erythrocyte samples were obtained from heparinized whole blood samples. Measurements for deformability were conducted on erythrocyte suspensions within serum physiologic tamponized with phosphate. Results: Diabetes led to increased relative resistance compared to group C however desflurane and sevoflurane did not alter erythrocyte deformability significantly in diabetic rats. Conclusion: Neither sevoflurane nor desflurane caused a negative effect on erythrocyte deformability in diabetic rats. However these findings should be further investigated in larger and more detailed studies.
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Objective To evaluate the effects of pyruvate Ringer' s solution on erythrocyte deformation function in the patients undergoing cardiopulmonary bypass (CPB) in vitro.Methods Thirteen patients of both sexes,aged 25-64 yr,of ASA physical status Ⅱ or Ⅲ (NAHY Ⅱ or Ⅲ),scheduled for elective cardiac valve replacement under CPB were enrolled in the study.At 10 and 60 min of CPB (T1,2) and 60 min after termination of CPB (T3),blood samples 18 ml were drawn from the radial artery and each patient's blood sample was equally divided into 6 parts (3 ml per part).The blood samples were divided into 3 groups (n =13 each):control group (group C),lactated Ringer's solution group (group R),and pyruvate Ringer's solution group (group P).In C,R and P groups,normal saline 1 ml,lactated Ringer's solution 1 ml,and pyruvate Ringer's solution 1 ml were added,respectively,and then the erythrocytes were incubated for 60 min at 37 ℃.At 30 and 60 min of incubation,the erythrocyte rigidity index (ERI) and erythrocyte deformation index (EDI) were detected.Results Compared with C and R groups,the ERI was significantly decreased at 30 and 60 min of incubation at T1,the EDI was decreased at 30 min of incubation at T1,2,and no significant change was found in ERI at T2,3 or in EDI at T3 in group P.There was no significant difference in ERI and EDI at different time points of incubation within groups.Conclusion Pyruvate Ringer's solution can enhance erythrocyte deformation function in the patients undergoing CPB.
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[Objective] Perspiration is almost only heat radiation mechanism under high temperature environments. And sudoriferous water is supplied from blood. Blood flow is determined by blood fluidity, blood volume and the cardiovascular system. It was reported that strong stress decreased blood fluidity.In this experiment, we investigated the relation between blood fluidity and water supply in rats loaded with forced exercise in high temperature environment.[Methods] SPF male Wistar rats weighing 250g were used. All animals were put in high temperature environment (Wet Bulb Globe Temperature; WBGT: 28°C) through whole experimental period. The rats were divided into four groups randomly; Suitable temperature environment-Exercise-Non water intake (SEN), High temperature environment-Exercise-Non water intake (HEN), High temperature environment-Exercise-Water intake (HEW) and Baseline (BL). In a group of water supply, distilled water was served before and later exercise by sonde forcibly. The blood was collected before or later of exercise and blood and erythrocyte suspension fluidity were measured.[Results] In the HEN, hydroperoxides, blood sodium, lactic acid and adrenaline increased while blood and erythrocyte suspension fluidity were decreased significantly compared with the BL. In addition, the hematocrit did not increase even if water equivalent to 4% of body weight lost it.[Conclusion] We speculate that exercise in high temperature environment decreases blood fluidity. However, the water supply in exercise that might not be sufficiently improve blood fluidity.
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BACKGROUND: Normal erythrocyte is deformable and this facilitates blood flow in the capillaries. Oxidative stress reduces the deformability of erythrocytes, and influences on blood flow in microcirculation. The objective of this study was to investigate the deformability of erythrocytes exposed to oxidative stress, the protective effects of verapamil and ascorbic acid against oxidative damages in erythrocytes, and the value of the microfluidic ektacytometer, RheoScan-D (RheoMeditech, Korea) in clinical application. METHODS: Effects of oxidative stress on erythrocytes were investigated using tert-butyl hydroperoxide (tBHP). Before exposure to tBHP, the erythrocytes were pretreated with verapamil and ascorbic acid to examine their protective effect against oxidative damages. The deformability of erythrocytes was measured by the microfluidic ektacytometer, RheoScan-D. RESULTS: When treated with tBHP, the deformability of erythrocytes was decreased (P<0.01) and methemoglobin (metHb) formation and mean corpuscular volume (MCV) of erythrocytes were increased (P<0.01, P<0.05) compared to those of the untreated control cells. Compared to the tBHP treated cells, pretreatment with verapamil increased the deformability of erythrocytes (P<0.01) and decreased metHb formation (P<0.01) and MCV (P<0.05). Likewise, pretreatment with ascorbic acid increased the deformability of erythrocytes (P<0.01) and decreased metHb formation (P<0.01). CONCLUSIONS: Oxidative stress reduces the deformability of erythrocytes and the deformability could be one of markers for oxidative damage. Verapamil and ascorbic acid have protective role against tBHP induced oxidative stress. The ektacytometer, RheoScan-D used in this study is convenient for clinical measurement and could be used in various fields of clinical medicine.
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Adult , Humans , Male , Antioxidants/pharmacology , Ascorbic Acid/pharmacology , Calcium Channel Blockers/pharmacology , Erythrocyte Deformability/drug effects , Erythrocytes/drug effects , Microfluidic Analytical Techniques/instrumentation , Oxidative Stress , Statistics, Nonparametric , Verapamil/pharmacology , tert-Butylhydroperoxide/pharmacologyABSTRACT
Objective:To observe DUXIL's curative effects and mechanisms for cerebral ischemia and anoxia secondary to the alteration of altering the number and configuration of human erythrocyte,which results in cerebral microcirculatory disturbance and dysunction of cerebrum.Methods:The patients were divided into two groups randomly and each group had 20 patients who had the prodrome of cerebral ischemia and anoxia.One group took DUXIL and the other NIMODIPINE for 15 days for comparison.Blood test and CVA were performed separately before and after the treatment.Twenty patients were chosed randomly from each group for SPECT.Results:There are varging degrees increases of parameters of erythrocyte acompanyed by alteration of parameters of CVA before treatment and SPECT qualitative analysis shows areas of low perfusion with differents severities.The number and configuration of erythrocyte was changed in group taken DUXIL.The parameters of CVA had been improved and the defect of encephalic perfusion also amended.The clinical symptoms were alleviated or disappeared.But no improvement were obtained in the other group.Conclusion:DUXIL can improve symptoms of cerebral ischemia and anoxia by affecting erythrocyte to make it have more favourable erythrocyte deformability(ED),which can contribute to effective perfusion of cerebral microcirculation.
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Objective To observe the characteristics of hemorheologic changes of hyperlipidemia rats at an early stage and to explore the mechanism of myocardial ischemic injury.Methods Seventy-two SD rats which were fed with high cholesterol diet(cholesterol+lard+pig bile salt) to result in hyperlipidemia model fell into HC group.Thirty-six SD rats which were fed with common diet fell into control group.The rats were fed for 10 to 90 d.At an interval of 10 d,9 time points were set.Therefore the 2 groups were randomly divided into 9 subgroups.At each time point,the changes of plasma lipids,cTnI,hemorheologic parameters,and pathological change of the rats’ myocardium and coronary vessel were assayed.Results The main characteristic of our models was hypercholesterolemia and high low-density-lipoproteins(LDL).With the extension of feeding time,plasma viscosity of HC group increased significantly,and erythrocyte deformability decreased.After fed with cholesterol for 50 d,myocardial ischemic injury occurred in the HC group.Correlation analysis revealed that the incidence of myocardial ischemic injury in hyperlipidemia rats was closely related with hypercholesterolemia and high low-density-lipoproteins.Conclusion The abnormal change of hemorheologic characteristics of hypercholesterolemia is a cause of myocardial ischemic injury.
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Objective Our study is to observe the effects of conjugated equine estrogen (CEE) combined with medroxyprogesterone acetate (MPA) on hemorheology in postmenopausal women in order to evaluate mechanism responsible for the increase in the incidence of cardiovascular disease after menopause and also to provide proper instruction and advice of hormone replacement therapy (HRT) for postmenopausal women Methods 60 healthy postmenopausal women were assigned to 3 groups randomly, 20 cases in each group Group A: CEE 0 625 mg/d+MPA 2 mg/d+calcium carbonate co. (Ca D) 600 mg/d Group B: CEE 0 3 mg/d+MPA 2 mg/d+Ca D 600 mg/d Group C: Ca D 600 mg/d only served as control Measurements of hemorheological parameters were performed before and 6 months after treatment Results After 6 months of HRT, group A: blood viscosity under the shear rate of 94 5 s -1 dropped from (5 23? 0 37) mPa?s to (5 03? 0 43) mPa?s ( P 0 05) Conclusion Both different dosages of CEE have favor effects on blood viscosity and erythrocyte deformabillity, which could play the role in preventing cardiovascular disease in postmenopausal women
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Haemorheological changes, including blood viscosity (?b) and plasma viscosity (?p) measured on a cone-plate viscometer, erythrocyte aggregation calculated, erytkrocyte deformability (DI) determined by the nuclear pore microfiltration technique and red blood cell shape using scanning electromicroscopy, were observed in patients during anesthesia There acs a significant reduction in ?b (at shear rates range 7. 68- 307. 20 s-l ), ?p and haemotocrit after induction (preintubation ) and 30 min after enflurane in the presence of iv fentanyl, compared with pre-aneathesia, accompanying remarkable increased DI. No changes of erythrocyte shape, however, was found add, nor was the difference of the index between induction period and maintenance of anesthesia. These findings suggest that general anesthesia leads to haemorheological alterations which may improve the microcirculation of the patients.
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To explore the mechanism of protecting erythrocyte deformability (ED) of polysaccharide sulfate(PSS)and propyllene glycolmannurate sulfate(PGMS) in patients with acute myocardial infarction (AMI). The erythrocyte filtration index(EFI),erythrocgte membrane Na+,K+-ATPase .glutathione peroxidase(GSH-Px)activity and lipid peroxide(LPO) were measured in 52 patients with AMI. Meanwhile the effects of PSS and PGMS on EFI, Na+,K+-ATPase ,GSH-Px and LPO in AMI patients were observed in vitro. The results showed that the EFI and LPO were markedly higher ,Na+ ,K+-ATP ase and GSH-Px were si-hnificantly lower in patients than those in control(P0. 05). These results indicate that PSS and PGMS could improve the ED in patients ,and the efficacy of PSS or PGMS was related to enchancement of erythrocyte membrane ATP-ase anci GSH-Px activity.
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BACKGROUND: To pass through the microcirculation, erythrocytes need to undergo considerable deformation. We performed an experiment to investigate the erythrocyte deformability in healthy adults and in patients with uncontrolled hypertension and controlled hypertension. METHODS: 5ml of whole blood is anticoagulated with 2mg ethylenediaminotetra-acetic acid(EDTA). 1ml graduated plastic syringe, without its plunger, is filled with anticoagulated whole blood to the 1ml mark, And the syringe is put into the assembled membrane holder. Under standard condition, whole blood is passed through a 5micro polycarbonate membrane filter under negative pressure of 20cm H2O. The studies are performed at roon temperature and within two hours of venipuncture. RESULTS: Erythrocyte deformability was observed in 91 normal healthy adults and 25 patients with uncontrolled hypertension and 18 patients with controlled hypertension. Following results were obtained. 1) In male control age group I, II, III, the erythrocyte deformability indices were 0.776+/-0.125, 0.792+/-0.189, and 0.714+/-0.172 respectively and in female the indices were 0.880+/-0.138, 0.865+/-0.182 and 0.796+/-0.170 accordingly. 2) THe RBC deformability indices in female control troup were significantly higher than the male group in statistics(p0.05). CONCLUSION: This study reveals that the erythrocyte deformability in patients with essential hypertension is significantly lower than the healthy adults.
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Adult , Female , Humans , Male , Erythrocyte Deformability , Erythrocytes , Hypertension , Membranes , Microcirculation , Phlebotomy , Plastics , SyringesABSTRACT
AIM: To study the changes of excretive amount of albumin(ALB) , N-acetyl-beta-D-glucosaminidase(NAG) in patients with high altitude polycythemia(HAPC) at different altitude and its mechanism. METHODS: Urinary ALB, NAG, activity of red blood cell superoxide dismutase(RBC-SOD), malonyldialdehyde(MDA) and erythrocyte filtration index(EFI) of 231 healthy subjects and 86 patients with HAPC at different altitude were detected. RESULTS:Excretive amount of urinary ALB, NAG, and plasma MDA, EFI were higher,and RBC-SOD was lower in patients with HAPC than those in healthy subjects, the changes were significantly obvious, with increasing altitude. Urinary ALB and NAG were negatively correlates to EFI, and no correlated to the content of MDA and RBC-SOD. CONCLUSIONS: EFI exertes an independent influence on urinary ALB and NAG. The decrease in erythrocyte deformability caused by the increase of peroxidation of lipids might participate in the pathogenesis and progress of the increase of excretive amount of ALB and NAG in HAPC.
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cholesterol/phospholipid ratio.