Osmotic fragility of red blood cells, lipid peroxidation and Ca2+-ATPase activity of placental homogenates and red blood cell ghosts in salt-loaded pregnant rats

2015 ◽  
Vol 29 (2) ◽  
pp. 229-233 ◽  
Author(s):  
Deliana Rojas ◽  
Freddy Rodríguez ◽  
Juvell Barráez ◽  
Sandy Piñero ◽  
Delia I. Chiarello ◽  
...  
2004 ◽  
Vol 5 (1) ◽  
pp. 37-50 ◽  
Author(s):  
P. Vague ◽  
T. C. Coste ◽  
M. F. Jannot ◽  
D. Raccah ◽  
M. Tsimaratos

Na+,K+-ATPase is an ubiquitous membrane enzyme that allows the extrusion of three sodium ions from the cell and two potassium ions from the extracellular fluid. Its activity is decreased in many tissues of streptozotocin-induced diabetic animals. This impairment could be at least partly responsible for the development of diabetic complications.Na+,K+-ATPase activity is decreased in the red blood cell membranes of type 1 diabetic individuals, irrespective of the degree of diabetic control. It is less impaired or even normal in those of type 2 diabetic patients. The authors have shown that in the red blood cells of type 2 diabetic patients,Na+,K+-ATPase activity was strongly related to blood C-peptide levels in non–insulin-treated patients (in whom C-peptide concentration reflects that of insulin) as well as in insulin-treated patients. Furthermore, a gene-environment relationship has been observed. The alpha-1 isoform of the enzyme predominant in red blood cells and nerve tissue is encoded by theATP1A1gene.Apolymorphism in the intron 1 of this gene is associated with lower enzyme activity in patients with C-peptide deficiency either with type 1 or type 2 diabetes, but not in normal individuals. There are several lines of evidence for a low C-peptide level being responsible for lowNa+,K+-ATPase activity in the red blood cells. Short-term C-peptide infusion to type 1 diabetic patients restores normalNa+,K+-ATPase activity. Islet transplantation, which restores endogenous C-peptide secretion, enhancesNa+,K+-ATPase activity proportionally to the rise in C-peptide. This C-peptide effect is not indirect. In fact, incubation of diabetic red blood cells with C-peptide at physiological concentration leads to an increase ofNa+,K+-ATPase activity. In isolated proximal tubules of rats or in the medullary thick ascending limb of the kidney, C-peptide stimulates in a dose-dependent mannerNa+,K+-ATPase activity. This impairment inNa+,K+-ATPase activity, mainly secondary to the lack of C-peptide, plays probably a role in the development of diabetic complications. Arguments have been developed showing that the diabetesinduced decrease inNa+,K+-ATPase activity compromises microvascular blood flow by two mechanisms: by affecting microvascular regulation and by decreasing red blood cell deformability, which leads to an increase in blood viscosity. C-peptide infusion restores red blood cell deformability and microvascular blood flow concomitantly withNa+,K+-ATPase activity. The defect in ATPase is strongly related to diabetic neuropathy. Patients with neuropathy have lower ATPase activity than those without. The diabetes-induced impairment inNa+,K+-ATPase activity is identical in red blood cells and neural tissue. Red blood cell ATPase activity is related to nerve conduction velocity in the peroneal and the tibial nerve of diabetic patients. C-peptide infusion to diabetic rats increases endoneural ATPase activity in rat. Because the defect inNa+,K+-ATPase activity is also probably involved in the development of diabetic nephropathy and cardiomyopathy, physiological C-peptide infusion could be beneficial for the prevention of diabetic complications.


2015 ◽  
Vol 135 (2) ◽  
pp. 88-93 ◽  
Author(s):  
Yi-Feng Tao ◽  
Zeng-Fu Deng ◽  
Lin Liao ◽  
Yu-Ling Qiu ◽  
Xue-Lian Deng ◽  
...  

Background: Osmotic fragility testing based on flow cytometry was recently introduced for the screening of hereditary spherocytosis (HS). This study was undertaken to evaluate the clinical diagnostic value of a flow-cytometric osmotic fragility test for HS. Methods: Peripheral blood was collected from 237 subjects at the First Affiliated Hospital of Guangxi Medical University, including 56 HS patients, 86 thalassemia patients and 95 healthy controls. The samples were examined by flow-cytometric osmotic fragility test and the percentage of residual red blood cells was used to determine HS. Peripheral blood smears were performed to examine the red blood cell morphology. Results: With clinical diagnosis of HS as the gold standard and the percentage of residual red blood cells <23.6% as the diagnostic threshold in the flow-cytometric osmotic fragility test, the sensitivity of the flow-cytometric osmotic fragility test for HS was 85.71% and the specificity was 97.24%. Conclusion: The flow-cytometric osmotic fragility test combined with a red blood cell morphology test by peripheral blood smear could be a simple, practical and accurate laboratory screening method for HS.


Lab on a Chip ◽  
2021 ◽  
Author(s):  
Yuncheng Man ◽  
Debnath Maji ◽  
Ran An ◽  
Sanjay Ahuja ◽  
Jane A Little ◽  
...  

Alterations in the deformability of red blood cells (RBCs), occurring in hemolytic blood disorders such as sickle cell disease (SCD), contributes to vaso-occlusion and disease pathophysiology. However, there are few...


1999 ◽  
Vol 277 (2) ◽  
pp. H508-H514 ◽  
Author(s):  
Charmaine B. S. Henry ◽  
Brian R. Duling

The endothelial cell glycocalyx influences blood flow and presents a selective barrier to movement of macromolecules from plasma to the endothelial surface. In the hamster cremaster microcirculation, FITC-labeled Dextran 70 and larger molecules are excluded from a region extending almost 0.5 μm from the endothelial surface into the lumen. Red blood cells under normal flow conditions are excluded from a region extending even farther into the lumen. Examination of cultured endothelial cells has shown that the glycocalyx contains hyaluronan, a glycosaminoglycan which is known to create matrices with molecular sieving properties. To test the hypothesis that hyaluronan might be involved in establishing the permeation properties of the apical surface glycocalyx in vivo, hamster microvessels in the cremaster muscle were visualized using video microscopy. After infusion of one of several FITC-dextrans (70, 145, 580, and 2,000 kDa) via a femoral cannula, microvessels were observed with bright-field and fluorescence microscopy to obtain estimates of the anatomic diameters and the widths of fluorescent dextran columns and of red blood cell columns (means ± SE). The widths of the red blood cell and dextran exclusion zones were calculated as one-half the difference between the bright-field anatomic diameter and the width of the red blood cell column or dextran column. After 1 h of treatment with active Streptomyces hyaluronidase, there was a significant increase in access of 70- and 145-kDa FITC-dextrans to the space bounded by the apical glycocalyx, but no increase in access of the red blood cells or in the anatomic diameter in capillaries, arterioles, and venules. Hyaluronidase had no effect on access of FITC-Dextrans 580 and 2,000. Infusion of a mixture of hyaluronan and chondroitin sulfate after enzyme treatment reconstituted the glycocalyx, although treatment with either molecule separately had no effect. These results suggest that cell surface hyaluronan plays a role in regulating or establishing permeation of the apical glycocalyx to macromolecules. This finding and our prior observations suggest that hyaluronan and other glycoconjugates are required for assembly of the matrix on the endothelial surface. We hypothesize that hyaluronidase creates a more open matrix, enabling smaller dextran molecules to penetrate deeper into the glycocalyx.


2018 ◽  
Vol 42 (3) ◽  
pp. 151-157 ◽  
Author(s):  
Antony P McNamee ◽  
Kieran Richardson ◽  
Jarod Horobin ◽  
Lennart Kuck ◽  
Michael J Simmonds

Introduction: Accumulating evidence demonstrates that subhaemolytic mechanical stresses, typical of circulatory support, induce physical and biochemical changes to red blood cells. It remains unclear, however, whether cell age affects susceptibility to these mechanical forces. This study thus examined the sensitivity of density-fractionated red blood cells to sublethal mechanical stresses. Methods: Red blood cells were isolated and washed twice, with the least and most dense fractions being obtained following centrifugation (1500 g × 5 min). Red blood cell deformability was determined across an osmotic gradient and a range of shear stresses (0.3–50 Pa). Cell deformability was also quantified before and after 300 s exposure to shear stresses known to decrease (64 Pa) or increase (10 Pa) red blood cell deformability. The time course of accumulated sublethal damage that occurred during exposure to 64 Pa was also examined. Results: Dense red blood cells exhibited decreased capacity to deform when compared with less dense cells. Cellular response to mechanical stimuli was similar in trend for all red blood cells, independent of density; however, the magnitude of impairment in cell deformability was exacerbated in dense cells. Moreover, the rate of impairment in cellular deformability, induced by 64 Pa, was more rapid for dense cells. Relative improvement in red blood cell deformability, due to low-shear conditioning (10 Pa), was consistent for both cell populations. Conclusion: Red blood cell populations respond differently to mechanical stimuli: older (more dense) cells are highly susceptible to sublethal mechanical trauma, while cell age (density) does not appear to alter the magnitude of improved cell deformability following low-shear conditioning.


2019 ◽  
Vol 39 (3) ◽  
pp. 271
Author(s):  
Hyunjung Kim ◽  
Young Ok Kim ◽  
Yonggoo Kim ◽  
Jin-Soon Suh ◽  
Eun-Jung Cho ◽  
...  

2018 ◽  
Vol 1 (5) ◽  
Author(s):  
Junbei Bai

Objective To observe the national elite male rowers blood, red blood cell activity and serum copper, zinc, calcium, magnesium and iron content of the five elements, and compared with the ordinary people. Aimed to investigate the between athletes, athletes and ordinary differences between the two sets of indicators and to explore the impact of element contents in red blood cell activity and five factors. Trying to bring two sets of indicators and specific combining ability, used in training on the monitoring function, and for the future to provide some references for further study. Methods It was included 22 athletes and 22 ordinary men, as the research object, in the collection of blood, measuring red blood cell activity in the blood content of the five elements, simultaneous measurement of physical indicators , will be doing all the data at the differences between the two groups compared to the group to do correlation analysis. The recent record of 2000m, 6000m rowing Dynamometer test results, and red blood cell activity associated with the five elements of content analysis. Results 1. Athletes indicators related to aerobic exercise were significantly higher than ordinary people. The white blood cells of athletes group were average.It shows that athletes have high aerobic capacity, while white blood cells are more stable than normal people. The members of the national rowing men's iron, magnesium content was significantly higher than ordinary group, the iron content is higher than the normal reference value; blood calcium levels were significantly lower than ordinary people, and lower than the normal reference value. The total number of red blood cells and the number of living cells was very significant positive correlation in two groups subjects; Red blood cell activity and red blood cell diameter is proportional, and red blood cell roundness in inverse proportion to the relationship; from this experiment a special ability to see red blood cell activity and there is no correlation. In both groups, hemoglobin was positively correlated with iron content, while iron was positively correlated with copper content. Conclusions 1. Increasing the number and volume of red blood cells can effectively increase the activity of red blood cells; red blood cell activity has no correlation with specific ability, and can not be used as an indicator to determine specific ability. The content of iron and magnesium in rowers is higher than that in ordinary people, which indicates that the adjustment of aerobic capacity and nerve control is very effective. The lower calcium content indicates that the injury caused by calcium loss should be prevented and the urgency of calcium supplementation should be emphasized. In training, we should pay attention to increasing hemoglobin content and aerobic capacity by supplementing iron. We can further consider the effect of supplementing copper to promote iron supplementation.


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