Effect of high glucose concentrations on human erythrocytes in vitro

Abstract

Exposure to high glucose concentrations in vitro is often employed as a model for understanding erythrocyte modifications in diabetes. However, effects of such experiments may be affected by glucose consumption during prolonged incubation and changes of cellular parameters conditioned by impaired energy balance. The aim of this study was to compare alterations in various red cell parameters in this type of experiment to differentiate between those affected by glycoxidation and those affected by energy imbalance. Erythrocytes were incubated with 5, 45 or 100 mM glucose for up to 72 h. High glucose concentrations intensified lipid peroxidation and loss of activities of erythrocyte enzymes (glutathione S-transferase and glutathione reductase). On the other hand, hemolysis, eryptosis, calcium accumulation, loss of glutathione and increase in the GSSG/GSH ratio were attenuated by high glucose apparently due to maintenance of energy supply to the cells. Loss of plasma membrane Ca2+-ATPase activity and decrease in superoxide production were not affected by glucose concentration, being seemingly determined by processes independent of both glycoxidation and energy depletion. These results point to the necessity of careful interpretation of data obtained in experiments, in which erythrocytes are subject to treatment with high glucose concentrations in vitro.

In vitro particulate analogue fluids for experimental studies of rheological and hemorheological behavior of glucose-rich RBC suspensions

“…A normal blood glucose level in nondiabetic humans (as our healthy donor), before a meal, is about 5 mM, so 100 mM represents a very high glucose concentration. 25,28 After the incubation time, the RBCs were washed twice with PBS in order to remove any remaining traces of the glucose-rich medium. Finally, we resuspended the glucose-rich RBCs at the desired Hct in Dx 40 to perform all the experiments.…”

“…This could be explained by the difficulty of the glucose-rich RBCs in recovering their original shape due to the reduction in their membrane viscoelastic properties. 24,25 The PMMA microbeads also show some deformation; however, a quick recover is observed in Regions 2 and 3. Hence, by performing the deformability tests, we have demonstrated that the less deformable cells correspond to pathological in vitro RBCs.…”

“…In Fig. 3, it 25,[27][28][29] In contrast, the results obtained for Region 3 show that glucose-rich RBCs have a larger DIs when compared with the healthy RBCs. This could be explained by the difficulty of the glucose-rich RBCs in recovering their original shape due to the reduction in their membrane viscoelastic properties.…”

“…As a consequence, there is an increase in the internal viscosity of RBCs due to structural alterations in the hemoglobin molecule and also an enhancement of aggregate formation that increases the blood viscosity. 24,25 Hyperglycemia is the most important factor on the onset, and the progress of diabetic complications and untreated hyperglycemia can cause long-term complications.…”

Synthesis of poly(HEMA‐co‐AAm) hydrogels by visible‐light photopolymerization of aqueous solutions containing aspirin or ibuprofen: analysis of the initiation mechanism and the drug release

“…In accordance with cell‐culture assays, where cell death is monitored by membrane disruption, hemolysis of red blood cells can be regarded as a mode of measuring death of erythrocytes . In this assay, the cytotoxicity produced by HG of different compositions, upon erythrocyte cells, was evaluated.…”