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1.
The effect of an intrinsic defect in the red cell and pronounced hypochromia on oxidative damage to RBC membrane lipids was compared in beta-thalassemia and iron deficiency anemia (IDA), which have a varied etiology but equivalent low hemogiobin content. The study was planned to correlate the etiology of the disorders to the severity of lipid imbalance and RBC hemolysis in membranes of both the conditions. Results indicated a fall of lysophosphatidylcholine(LPC), phosphatidylethanolamine(PE) and the unsaturated to saturated fatty acid ratio in both conditions, while phosphatidylcholine(PC) increased only in thalassemia. However, irrespective of the disease, sphingomyelin(SM), total cholesterol and phospholipid levels elevated and the hydrogen peroxide stress test indicated increased susceptibility of both pathologic RBCs to peroxidation. Present findings indicate that IDA and thalassemla, allow for considerable amounts of oxidative damage to membrane lipids, irrespective of their etiologles, and thus point hypochromia as an important contributor for inducing lipid imbalance and RBC hemolysis.  相似文献   

2.
Reactive oxygen species (ROS) cause damage to the DNA producing mutations and formation of tumours such as carcinoma of breast. Tumour cells are known to produce ROS at a greater pace than the non-transformed cells. The increased production of reactive oxygen species causes oxidative stress leading to cell proliferation and hence increased inflammatory conditions. The present study was aimed to investigate the role of oxidative stress in the pathogenesis of breast cancer. Females suffering from breast cancer had significantly decreased Superoxide dismutase (SOD) and reduced glutathione (GSH) levels in comparison to normal females. The compromised antioxidant defence system produces the oxidative stress which in turn creates the inflammatory response shown by concomitant increased adenosine deaminase (ADA) activity in female patients. ADA diminishes the protective molecule adenosine. There were significant variations (p < 0.01) in ADA activity with different clinical stages (stage 1–4) of breast cancer suggesting thereby that estimation of ADA activity can be used as a diagnostic tool to detect the stage of cancer along with cytological studies. Mastectomy was performed and post-operatively serum SOD and ADA activity and plasma GSH levels were estimated. There was a statistically significant increase in activity of SOD and levels of GSH while serum ADA activity decreased significantly, suggesting thereby that oxidative stress is responsible for increased cell proliferation and hence the inflammatory conditions in CA breast that got ameliorated post-operatively.  相似文献   

3.
An unexpected increase in erythrocyte osmotic resistance during viral hepatitis in two patients prompted study of effects of hepatitis (in Karad) on osmotic resistance. The test was performed by placing erythrocytes in saline solutions of decreasing osmolarity and osmotic fragility defined in terms of the saline concentration at which hemolysis begins. Study included 44 infected subjects (acute viral hepatitis non-A non-B). All forty four infected subjects showed abnormal results when compared to normal subjects. increased erythrocyte osmotic resistance i.e. hemolysis begins between 0.45% to 0.40% of NaCl and is completed between 0.25% to 0.20% NaCl, whereas in normal subjects. hemolysis begins between 0.50% to 0.45% NaCl and is completed between 0.35% to 0.30% NaCl. Osmotic resistance was observed with increase in total bilirubin (mean±SD) (4.6 ±3.6), direct bilirubin (3.0±2.5), SGOT (58.8±55.5) SGPT (114.2±150.3) activity. Physiologic shifts in erythrocyte osmotic resistance may be due to changes in membrane lipid ratio.  相似文献   

4.
A comparative study was conducted to evaluate calcineurin activity in normal pancreatic beta cells and insulinoma cells in relation to their oxidative state. In comparison to normal islets, insulinoma cells had enhanced oxidative stress as evidenced by increased content of thiobarbituric acid reactive substances. In addition, diminished activity of calcineurin in insulinoma cells was concomitant with decreased content of reduced glutathione and glutathione peroxidase activity signifying diminished antioxidant status in these cells. Culturing insulinoma cells in presence of the calcineurin inhibitor cyclosporin A resulted in further decrease of calcineurin activity with restoration of glutathione peroxidase but without restoration of reduced glutathione levels. These results indicate that an estimate of oxidative stress in pancreatic islets and insulinoma cells can be obtained by assaying calcineurin activity.  相似文献   

5.
Red blood cells (RBCs) possess a unique capacity for undergoing cellular deformation to navigate across various human microcirculation vessels, enabling them to pass through capillaries that are smaller than their diameter and to carry out their role as gas carriers between blood and tissues. Since there is growing evidence that red blood cell deformability is impaired in some pathological conditions, measurement of RBC deformability has been the focus of numerous studies over the past decades. Nevertheless, reports on healthy and pathological RBCs are currently limited and, in many cases, are not expressed in terms of well-defined cell membrane parameters such as elasticity and viscosity. Hence, it is often difficult to integrate these results into the basic understanding of RBC behaviour, as well as into clinical applications. The aim of this review is to summarize currently available reports on RBC deformability and to highlight its association with various human diseases such as hereditary disorders (e.g., spherocytosis, elliptocytosis, ovalocytosis, and stomatocytosis), metabolic disorders (e.g., diabetes, hypercholesterolemia, obesity), adenosine triphosphate-induced membrane changes, oxidative stress, and paroxysmal nocturnal hemoglobinuria. Microfluidic techniques have been identified as the key to develop state-of-the-art dynamic experimental models for elucidating the significance of RBC membrane alterations in pathological conditions and the role that such alterations play in the microvasculature flow dynamics.  相似文献   

6.
Red blood cells (RBC) from iron-deficient chidren were found to have decreased levels of reduced glutathione and reduced content of glucose-6-phosphate dehydrogenase, glutathione peroxidase and glutathione reductase than RBC from normal control children. These findings suggest an increased oxidant stress on iron-deficient red cells which may be one of the mechanisms responsible for membrane alterations leading to shortened life span of erythrocytes in iron-deficiency anaemia.  相似文献   

7.
Cholinesterases belongs to class hydrolases. There are two types acetylcholinesterase and butyryl cholinesterase. Acetylcholinesterase present in nerve endings and also in the RBC membrane. It helps to maintain the shape and size of RBCs. Any change in shape and size of RBCs may affect the activity of Acetylcholinesterase. Thus this study aimed to estimate RBCs Acetylcholinesterase enzyme activity in various types of anemias and correlate the RBCs Acetylcholinesterase enzyme activity with various hematological indices such as Erythrocyte Sedimentation Rate (ESR), Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Hemoglobin Concentration (MCHC), Mean Corpuscular Volume (MCV), Red cell Distribution Width (RDW) etc. After obtaining ethical approval from Institutional ethics committee total of 100 samples were collected from Clinical Biochemistry laboratory, Kasturba Medical College, Manipal, Manipal University. 25 were having normal RBC indices, 12 with hemolytic anemia, 26 with microcytic anemia and 26 with macrocytic anemia based on peripheral smear report and RBC indices. Acetylcholinesterase were measured using Ellman’s method. RBC acetylcholinesterase activity was significantly increased in microcytic anemia (58.13 ± 5.4) and macrocytic anemia (76.87 ± 6.7) than normal group (37.62 ± 2.71). Also increased RBC acetylcholinesterase was seen in hemolytic anemia (48.11 ± 5.18) but the increase is not statistically significant. RBC acetylcholinesterase correlated negatively with hemoglobin (r = ?0.356, p = 0.001) and positively with RDW (r = 0.31, p = 0.003). To conclude RBC acetylcholinesterase activity can be used as one of the potential marker for various types of anemia.  相似文献   

8.
The main objective of the study was to assess the oxidative stress in plasma and erythrocytes of rheumatoid arthritis patients by measuring the levels of thiobarbituric acid reactive substances (TBARS), non-enzymatic antioxidants (vitamin E, C and reduced glutathione) and enzymatic antioxidants [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHPx)]. This study has been conducted on twenty-two adult female rheumatoid arthritis patients and an equal number of healthy subjects. Elevated lipid peroxidation and multidirectional changes in the antioxidant defence system were noticed in patients with rheumatoid arthritis. The enhanced lipid peroxidation accompanied by disturbance in antioxidant status indicates that rheumatoid arthritis patients are more prone to free radical mediated oxidative damage.  相似文献   

9.
Lipid peroxidation and hemolysis in humand red blood cells (RBCs) increased on their exposure to increasing concentrations of lead acetate (0.01–1.0mM). However pretreatment of RBCs with ascorbic acid (2mM and 4mM) significantly reduced the effect of lead acetate on lipid peroxidation and hemolysis in human RBCs.  相似文献   

10.
Cryopreservation of human red blood cells (RBCs) in the presence of 40% glycerol allows a shelf-life of 10 years, as opposed to only 6 weeks for refrigerated RBCs. Nonetheless, cryopreserved blood is rarely used in clinical therapy, in part because of the requirement for a time-consuming (∼1 h) post-thaw wash process to remove glycerol before the product can be used for transfusion. The current deglycerolization process involves a series of saline washes in an automated centrifuge, which gradually removes glycerol from the cells in order to prevent osmotic damage. We recently demonstrated that glycerol can be extracted in as little as 3 min without excessive osmotic damage if the composition of the extracellular solution is precisely controlled. Here, we explore the potential for carrying out rapid glycerol extraction using a membrane-based microfluidic device, with the ultimate goal of enabling inline washing of cryopreserved blood. To assist in experimental design and device optimization, we developed a mass transfer model that allows prediction of glycerol removal, as well as the resulting cell volume changes. Experimental measurements of solution composition and hemolysis at the device outlet are in reasonable agreement with model predictions, and our results demonstrate that it is possible to reduce the glycerol concentration by more than 50% in a single device without excessive hemolysis. Based on these promising results, we present a design for a multistage process that is predicted to safely remove glycerol from cryopreserved blood in less than 3 min.  相似文献   

11.
Reactive oxygen species (ROS) are believed to be responsible for pathogenesis of various diseases affecting tissues and systems. ROS generated by mitochondrial electron transport chain as well as extra-mitochondrially are eliminated by the respective defense mechanisms. We checked the activity of ROS generating system such as xanthine oxidase and also the parameter of ROS defense mechanism e.g. superoxide dismutase (SOD), catalase, glutathione peroxidase (GPox), reduced glutathione content (GSH) and glucose-6-phosphate dehydrogenase (G6PDH) in mitochondrial and post-mitochondrial fractions from various tissues (liver, kidney, brain and heart) of normal rats. Extent of lipid peroxidation (LPO) which is immediate consequence of ROS generation was also examined. Our results shows that significant tissue-specific differences exist in mitochondrial and cytosolic ROS generating systems and ROS defense mechanisms.  相似文献   

12.
Alcohol induced oxidative stress is linked to the metabolism of ethanol. In this study it has been observed that administration of ethanol in lower concentration caused gain in body and liver weight. while higher concentration of ethanol caused lesser gain in body and liver weight. Ethanol treatment enhanced lipid peroxidation significantly, depletion in levels of hepatic glutathione and ascorbate, accompanied by a decline in the activities of glutathione peroxidase and glutathione reductase, and increased in hepatic glutathione s-transferase activity. Interestingly catalase activity increases in lower concentration of ethanol exposure, and decreased in higher concentration. Superoxide dismutase activity was also increased on ethanol exposure. But, ethanol feeding did not show any effect on glucose-6-phosphate dehydrogenase activity. Ethanol ingestion perturbs the antioxidant system in a dose and time dependent manner.  相似文献   

13.
Ethanol-induced liver injury may be linked, at least partly, to an oxidative stress resulting from increased free radical production and/or decreased antioxidant defence. Distinguishing alcoholic and non-alcoholic liver disease has important implications. This study looked at the possible changes between alcoholic and non-alcoholic liver diseases by examining the presence of oxidative damage, as monitored by several parameters relating to oxidative stress. Lipid peroxides concentration, superoxide dismutase activity and glutathione S-transferase activity increased, where as glutathione content, glutathione peroxidase activity and glutathione reductase activity decreased among the tested subjects in comparison to normal healthy group. Determination of these parameters may be valuable in the evaluation of liver disease. However, oxidative stress related enzymes and non-enzymes can not be utilized as a marker for alcoholic liver diseases, as these parameters responded in the same way after liver is damaged irrespective of their cause. Their level may help in determining the degree of liver damage. Degree of oxidative injury was similar in patients with non-alcoholic liver disease and in moderate drinkers; while significantly higher in heavy drinkers. The differences between the groups might be based on the type of liver pathological condition rather than its etiology (i.e. alcohol and non alcohol related causes).  相似文献   

14.
Glyco-oxidation is considered as a source of permanent, cumulative, oxidative damage to long lived proteins in ageing and in diabetes. Although RBC depends solely on glucose for energy purpose, hyperglycemic state glycosylates hemoglobin, creates oxidative stress and puts the cellular components at risk. In view of this, RBC membrane composition was analyzed in diabetic patients. The results were compared with healthy age and sex matched control groups. When RBC membrane components such as protein, sialic acid, phospholipids and cholesterol were determined in insulin dependent diabetes mellitus, a significant rise in phospholipids and cholesterol and significant fall in sialic acid and protein content was noted. RBC membrane composition showed pronounced alterations in insulin dependent diabetes mellitus. These changes were accompanied by higher levels of lipid peroxidation products like Malondialdehyde.  相似文献   

15.
The excessive generation of reactive oxygen species (ROS) by abnormal spermatozoa and contaminating leukocytes has been defined as one of the few etiologies for male infertility. Administration of antioxidants in patients with ‘male factor’ infertility has begun to attract considerable interest. The main difficulty of such an approach is our incomplete understanding of the role of free radicals in normal and abnormal sperm function leading to male infertility. Mammalian spermatozoa membranes are very sensitive to free radical induced damage mediated by lipid peroxidation, as they are rich in polyunsaturated fatty acids. Limited endogenous mechanisms exist to reverse these damages. ROS attacks the fluidity of the sperm plasma membrane and the integrity of DNA in the sperm nucleus. ROS induced DNA damage accelerate the germ cell apoptosis. Unfortunately spermatozoa are unable to repair the damage induced by excessive ROS as they lack the cytoplasmic enzymes required to accomplish the repair. Assessment of such oxidative stress status (OSS) may help in the medical treatment. Treatment strategies must be directed toward lowering of ROS levels to keep only a small amount necessary to maintain normal cell function.  相似文献   

16.
It is clear that Haptoglobin binds to Hemoglobin strongly and irreversibly. This binding, protects body tissues against heme-mediated oxidative tissue damages via peroxidase activity of Haptoglobin–Hemoglobin complex. Peroxidase activity of Haptoglobin(2-2)–Hemoglobin complex was determined via measurement of following increase in absorption of produced tetraguaiacol as the second substrate of Haptoglobin–Hemoglobin complex by UV–Vis spectrophotometer at 470 nm and 42°C. The results are showing that peroxidase activity of Haptoglobin(2-2)–Hemoglobin complex is modulated by homotropic effect of hydrogen peroxide as the allosteric substrate. On the other hand, antioxidant activity of Haptoglobin(2-2)–Hemoglobin is increased via heterotropic effect of two antibiotics (especially ampicillin) on the peroxidase activity of the complex. The condition of pathologic temperature along with the administration of ampicillin and/or coamoxiclav is in favor of amplification in antioxidant activity of Haptoglobin(2-2)–Hemoglobin and combating against free radicals in individuals with Hp2-2 phenotype. Therefore, oxidative stress effects have been diminished in the population with this phenotype.  相似文献   

17.
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18.
The confined flow of red blood cells (RBCs) in microvasculature is essential for oxygen delivery to body tissues and has been extensively investigated in the literature, both in vivo and in vitro. One of the main problems still open in microcirculation is that flow resistance in microcapillaries in vivo is higher than that in vitro. This discrepancy has been attributed to the glycocalyx, a macromolecular layer lining the inner walls of vessels in vivo, but no direct experimental evidence of this hypothesis has been provided so far. Here, we investigate the flow behavior of RBCs in glass microcapillaries coated with a polymer brush (referred to as “hairy” microcapillaries as opposed to “bare” ones with no coating), an experimental model system of the glycocalyx. By high-speed microscopy imaging and image analysis, a velocity reduction of RBCs flowing in hairy microcapillaries as compared to bare ones is indeed found at the same pressure drop. Interestingly, such slowing down is larger than expected from lumen reduction due to the polymer brush and displays an on-off trend with a threshold around 70 nm of polymer brush dry thickness. Above this threshold, the presence of the polymer brush is associated with an increased RBC deformation, and RBC velocity is independent on polymer brush thickness (at the same pressure drop). In conclusion, this work provides direct support to the hypothesis that the glycocalyx is the main factor responsible of the higher flow resistance found in microcapillaries in vivo.  相似文献   

19.
The changes in the erythrocyte lipid peroxidation products (MDA), levels of glutathione (GSH), ascorbic acid and plasma vitamin E (non enzymatic antioxidant parameters) and activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase in erythrocytes and plasma glutathione - S - transferase (GST) activity were estimated in patients with rheumatoid arthritis. This work was undertaken to assess oxidative stress and anti oxidant status in patients with rheumatoid arthritis. It was observed that there was a significant increase in erythrocyte MDA levels, activities of SOD, GPX, plasma GST and a significant decrease in erythrocyte GSH, ascorbic acid, plasma vitamin E levels and catalse activity in patients with rheumatoid arthritis when compared to controls. The results of our study suggests higher oxygen free radical production, evidenced by increased MDA and decreased GSH, ascorbic acid, vitamin E and Catalase activity, support to the oxidative stress in rheumatoid arthritis. The increased activities of antioxidant enzymes may be a compensatory regulation in response to increased oxidative stress.  相似文献   

20.
Advanced age is associated with an accumulation of free radical damage, which leads to physiological and clinical modifications. Age related changes resulting from free radical reactions include increasing levels of lipid peroxides, alterations in enzyme activities and greater osmotic fragility. The present study was conducted to estimate the level of lipid peroxidation product-Malondialdehyde and antioxidants Catalase and Glutathione in elderly people. An increase in lipid peroxidation and decrease in antioxidants was observed in normal elderly people. Highly significant increase in MDA and decrease in antioxidants was observed in elderly people when complicated with diabetes and hypertension. Supplementation of antioxidants may prevent further oxidative injury in elderly people.  相似文献   

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