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OBJECTIVE: Urea transporter-B (UT-B), highly expressed in erythrocyte, confers specific permeability to urea, urea analogues and water. The purpose of this study was to determine the hemorheological properties of UT-B null erythrocyte using a series of biophysical techniques. METHODS AND RESULTS: The blood was taken from UT-B knockout and wild-type mice and the hemorheological parameters were measured. The UT-B inhibitor, PU-14, was used to treat the erythrocyte of wild-type mice in vitro and the deformability of the treated erythrocyte was analyzed. The results showed that UT-B knockout improves the hemorheological properties of erythrocyte, including increased erythrocyte deformation index, small deformation index, orientation index, low osmotic fragility and high electrophoretic rate. The UT-B inhibitor PU-14 had the similar effect as UT-B knockout on the deformation indices. The whole blood viscosity in UT-B knockout mice showed reduction trend as compared to wild-type mice. CONCLUSIONS: The data indicate that UT-B is involved in the regulation of hemorheology, which suggests that UT-B may be a potential therapeutic target for improving the hemorheology in some metabolic and hereditary diseases. [ABSTRACT FROM AUTHOR]

Living-donor renal transplantation is an ideal treatment for patients with end stage renal disease because it affords earlier transplantation and better graft for long term survival. CD14+ monocytes are the predominant inflammatory cells in renal allograft intimal arteritis. The biomechanical alterations in CD14+ monocytes would affect the function of graft. The aim of the present study was to explore the changes in the biorheological properties of CD14+ monocytes before and after the living donor renal transplantation. We found that the viscoelastic properties of CD14+ monocytes were greatly decreased after renal transplantation. Confocal microscopy showed that the F-actin content was increased when the oral immunosuppressive agents started. We also found that two cytoskeletal regulatory proteins, cofilin1 and profilin1, changed. Our results suggest that the immunosuppressive agents could significantly change the biorheological characteristics of the CD14+ mononuclear cells and the biomechanical changes may greatly affects their function, which would play a critical role to gain longer immune-tolerance stage. [ABSTRACT FROM AUTHOR]

Living-donor renal transplantation is the preferred treatment for patients with end stage renal disease since it affords earlier transplantation and better graft for long term survival. The aim of the present study was to explore the hemorheological changes in patients undergone living-donor renal transplantation. We investigated the dynamic changes in the hemorheological properties of blood taken from the patients before renal transplantation and at 1 week, 2 week, 3 week and >1 month after the operation. As compared with pre-operation, the whole blood viscosity at different shear rates decreased significantly; the erythrocyte aggregation index decreased; the erythrocyte deformation index (DI) and integrated deformation index (IDI) had a remarkable improvement; the erythrocyte electrophoresis rate was rasied. We also found that the osmotic fragility of RBCs at 145 mOsm/kg was greatly decreased after renal transplantation. Importantly, the ratio of erythrocyte membrane protein 4.1 a to 4.1 b decreased, which may explain the changes in DI, IDI, and osmotic fragility. Our results suggest that these hemorheological changes may greatly improve the organ microcirculation, which would play a critical role in reduce the ischemia-reperfusion injury in the graft. [ABSTRACT FROM AUTHOR]

The differentiation, maturation and functioning of Dendritic cells (DCs) are dynamic processes. This study investigated the changes of DCs' migration ability and biorheological properties during their differentiation. Transmigration assay showed that, DCs' migration rate was improved significantly as they differentiate (p < 0.05); NSC (Rac1 blocker) treatment could significantly decrease their migration rates (p < 0.05). Confocal images showed that, F-actin uniformly distributed in monocytes; with DC's differentiation, F-actin began to remodel and gather at the site of dendrites; the images presented surface ruffles and uneven sawtooth-like cytoskeletal structures. Fluorescence polarization analysis showed that, membrane fluidity was increased significantly with DC's differentiation (p < 0.05). CD62L was upregulated significantly (p < 0.05) on the third and ninth days. CD2 was upregulated significantly (p < 0.05) until the seventh day. DC's electrophoretic mobility was increased continuously, especially increased significantly from the third day to the fifth day and the final stage (p < 0.05). These results indicate that there are significant changes in the biorheological properties of DCs during their differentiation. [ABSTRACT FROM AUTHOR]

Dichlorvos is an important insecticide used largely. Some studies have demonstrated that organophosphate pesticide has effects on erythrocyte membrane structures, which is critical to erythrocyte function and hemorheology. The aim of the present study was to explore the effect of oxidative stress on hemorheological changes during dichlorvos poisoning in rabbits. Data indicated that after dichlorvos exposure the hematocrit adjusted viscosity at high shear rate increased and erythrocyte membrane fluidity decreased. Data obtained from plasma showed that lipid peroxidative substance-malonaldehyde was elevated and superoxide dismutase was reduced. In summary, oxidative stress does occur in dichlorvos poisoning and may lead to hemorheological alterations. The changes of hemorheology may be responsible for the pathophysiology of the dichlorvos poisoning. [ABSTRACT FROM AUTHOR]

Erythroblasts were obtained from murine spleen. After cultured for 12 hr, the cells were divided into four groups with the use of the following cytokines in culture: EPO, EPO+SCF, EPO+IL-3, and EPO+IL-3+SCF. Cell proliferation assay was done. Apoptosis rates were obtained by using a flow cytometer. Mitochondrial membrane potential (MMP) was assessed in flow cytometry (FCM) by labeling with rhodamine 123. Mitochondrial enzyme activity (MEA) was evaluated with MTT colorimetric assay. The cells were labeled with Fluo-3/Am Ester and Ca2+ concentration was measured. The expression of Bax mRNA and Bcl-2 mRNA was analyzed by RT-PCR. At same time, the expression of Bax and Bcl-2 was analyzed by western blotting. Our results showed that IL-3 and SCF have synergistic effects with EPO on the proliferation, differentiation and apoptosis of erythroid progenitors. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the changes of hemorheological properties of erythrocytes in the nude mice with erythroleukemia and the treatment effects of etoposide (VP16). Thirty mice were randomly divided into three groups: the control group (C group), injected with 1 ml saline solution, the MEL group (M group) injected with 1 ml MEL (murine erythroleukemia cell line) and the MEL + VP16 group (V group) injected with 1 ml MEL and from the 8th day after injection, 20 μl VP16 (1 μg/μl) was injected intraperitoneally every five days. One week after MEL injection, erythroblastic cells increased in the bone marrow and proerythroblasts were found in the peripheral blood, suggesting that erythroleukemia was induced. Abnormalities were also found in spleens and livers later. At around twenty days after injection, the mice in M group died and about four weeks after injection, the mice in V group also died. Compared with C group, the hemorheological indexes [the deformation index DI, orientation index (DIor), and the small deformation index (DId)], electrophoretic mobility, membrane fluidity as well as osmotic fragility of red blood cells (RBC) in M and V groups changed significantly. But after VP16 administration, the changes of above parameters in V group were less significant than those of M group. The results above suggested that intraperitoneal injection of MEL cells could cause erythroleukemia in nude mice, VP16 could alleviate the erythroleukemia symptom and improve the hemorheological properties, and could prolong V group nude mice survival. [ABSTRACT FROM AUTHOR]