Reduced Stiffness and Augmented Traction Force in Type 2 Diabetic Coronary Microvascular Smooth Muscle.

Reduced Stiffness and Augmented Traction Force in Type 2 Diabetic Coronary Microvascular Smooth Muscle. Am J Physiol Heart Circ Physiol. 2020 May 01;: Authors: McCallinhart P, Cho Y, Sun Z, Ghadiali SN, Meininger GA, Trask AJ Abstract Type 2 diabetic (T2DM) coronary resistance microvessels (CRMs) undergo inward hypertrophic remodeling associated with reduced stiffness and reduced coronary blood flow in both mice and pig models. Since reduced stiffness does not appear to be due to functional changes in the extracellular matrix, this study tested the hypothesis that decreased CRM stiffness in T2DM is due to reduced vascular smooth muscle cell (VSMC) stiffness, which impacts the traction force generated by VSMCs. Atomic force microscopy (AFM) and traction force microscopy (TFM) were conducted on primary low-passage CRM VSMCs from normal Db/db and T2DM db/db mice, in addition to low-passage normal and T2DM de-identified human coronary VSMCs. Elastic modulus was reduced in T2DM mouse and human coronary VSMCs compared to normal (Mouse: Db/db: 6.84±0.34 kPa vs. db/db: 4.70±0.19 kPa, p<0.0001; Human: Normal: 3.59±0.38 kPa vs. T2DM: 2.61±0.35 kPa, p=0.05). Both mouse and human T2DM coronary microvascular VSMCs were less adhesive to fibronectin compared to normal. T2DM db/db coronary VSMCs generated enhanced traction force by TFM (Control: 692±67 Pa vs db/db: 1507±207 Pa; p<0.01). Immunoblot analysis showed that T2DM human coronary...
Source: Physiological Research - Category: Physiology Authors: Tags: Am J Physiol Heart Circ Physiol Source Type: research