Critical Shear Stress is Associated with Diabetic Kidney Disease in Patients with Type 2 Diabetes

Critical shear stress of red blood cells as a novel integrated biomarker for screening chronic kidney diseases in cases of type 2 diabetes

BACKGROUND:

The glomerular filtration rate (GFR) and albumin-to-creatinine ratio (ACR) have been widely used to identify and manage diabetic kidney disease (DKD). However, classifications based on these two indices do not always concur in terms of DKD diagnosis; for example, cases of high ACR with normal GFR or normal ACR with low GFR may occur. A recent study suggested that critical shear stress (CSS), a hemorheological parameter to represent aggregating force of red blood cells (RBCs), is a potential screening index for DKD. In the present study, we investigated the diagnostic potential of CSS for DKD according to the KDIGO 2012 Guideline.

METHODS:

A total of 378 patients with type 2 diabetes who visited Yeungnam University Hospital between 2014 and 2017 were included. CSS was measured using a transient microfluidic hemorheometer, Rheoscan-D300® (Rheomeditech, Seoul, Republic of Korea) with whole blood. Patients who were DKD negative (green zone) were compared with patients who were DKD positive (red zone) as Model 1 and patients at risk for (orange zone) and red zones as Model 2, respectively.

RESULTS:

After exclusion criteria such as eGFR < 30 mL/min/1.73 m², alcoholism, and macrovascular complications were applied, the sensitivity and specificity were 100% and 77.8% for Model 1 and 75.0% and 72.0% for Model 2, respectively. The diagnostic accuracy measures of the CSS for Model 1 were found to be highly accurate or have the potential to alter clinical decisions. Similarly, the diagnostic accuracy measures of CSS for Model 2 were found to provide useful information, despite them expanding to the orange and red zones.

CONCLUSION:

DKD was successfully identified using a novel integrated hemorheological index of CSS that satisfied both ACR and GFR criteria. Therefore, CSS may be useful for the additive diagnosis of DKD with GFR and uACR.

The Relationship between Erythrocytes and Diabetes Mellitus

High blood glucose level (hyperglycemia) is a leading indicator of diabetes mellitus (DM). Erythrocytes are the most abundant cells in the circulation and the first to perceive changes in plasma composition. Long-lasting hyperglycemia affects the structure and function of erythrocytes. The detection of erythrocyte-related indicators can provide a valuable reference for the prevention, diagnosis, and treatment of DM and its complications. This paper reviews the normal structure and function of erythrocytes, the changes in erythrocytes in patients with diabetes, and the role of erythrocytes in the development of diabetic complications to provide more indicators for the early prevention of DM complications and to monitor the therapeutic effect of DM.

Assessment of Fibrinogen Macromolecules Interaction with Red Blood Cells Membrane by Means of Laser Aggregometry, Flow Cytometry, and Optical Tweezers Combined with Microfluidics

An elevated concentration of fibrinogen in blood is a significant risk factor during many pathological diseases, as it leads to an increase in red blood cells (RBC) aggregation, resulting in hemorheological disorders. Despite the biomedical importance, the mechanisms of fibrinogen-induced RBC aggregation are still debatable. One of the discussed models is the non-specific adsorption of fibrinogen macromolecules onto the RBC membrane, leading to the cells bridging in aggregates. However, recent works point to the specific character of the interaction between fibrinogen and the RBC membrane. Fibrinogen is the major physiological ligand of glycoproteins receptors IIbIIIa (GPIIbIIIa or αIIββ3 or CD41/CD61). Inhibitors of GPIIbIIIa are widely used in clinics for the treatment of various cardiovascular diseases as antiplatelets agents preventing the platelets’ aggregation. However, the effects of GPIIbIIIa inhibition on RBC aggregation are not sufficiently well studied. The objective of the present work was the complex multimodal in vitro study of the interaction between fibrinogen and the RBC membrane, revealing the role of GPIIbIIIa in the specificity of binding of fibrinogen by the RBC membrane and its involvement in the cells’ aggregation process. We demonstrate that GPIIbIIIa inhibition leads to a significant decrease in the adsorption of fibrinogen macromolecules onto the membrane, resulting in the reduction of RBC aggregation. We show that the mechanisms underlying these effects are governed by a decrease in the bridging components of RBC aggregation forces.