The Mechanical Characteristics of Human Endothelial Cells in Response to Single Ionizing Radiation Doses By Using Micropipette Aspiration Technique

Abstract

The mechanical properties of living cells are known to be promising biomarkers when investigating the health and functions of the human body. Ionizing irradiation results in vascular injury due to endothelial damage. Thus, the current study objective was to evaluate the influence of continuous radiation doses on the mechanical properties of human umbilical vein endothelial cells (HUVECs), and to identify Young's modulus (E) and viscoelastic behavior. Single-dose (0, 2, 4, 6, and 8 Gy) radiation was applied to HUVECs using a Cobalt-60 treatment machine in the current vitro irradiation study. Thereafter, a micropipette-aspiration technique was used to measure the elastic modulus of the HUVECs in control and radiation-induced samples. Confocal imaging was then performed for following of the cytoskeletal reorganization of the HUVECs in response to the different radiation doses. Significant enhanced adhesion of the elastic modulus of the HUVECs was observed. The dose value was seen to increase from 0 Gy to 8 Gy. A linear relationship was observed between the 0 Gy and 8 Gy doses following an examination of the dose-response curve for elastic modulus after irradiation. The correlation coefficient was found to be 0.955 and the sensitivity of the dose-elastic modulus to be 7.69 Pa..Gy-1 following analysis of the linear portion of the response curve. Also, a significant increment in stiffness accompanied with the considerable drop in creep compliance curve was detected in radiation-induced groups. Biomechanics-based analysis can provide a platform from which to assess the response of the endothelium to radiation when studying vascular system behavior during the cancer therapy process.

Recent Advances on the Model, Measurement Technique, and Application of Single Cell Mechanics

“…E = σ/ε, the ratio of stress to strain. [7,17,18,38,39,43,48,69,70,[105][106][107]123,125,126,133,134,[139][140][141][142][143]149,152,155] Shear modulus (G)…”

“…The reason for the difference was analyzed, and it was considered that the cell adhesion characteristics and the nonuniformity of the internal skeleton affected the overall mechanical properties of the cells. Alireza [ 70 ] used micropipette aspiration technology, combined with confocal technology, to obtain Young’s modulus and viscosity characteristics of human umbilical vein endothelial cells in order to study the changes in the mechanical performances of cells under single electric radiation. It was found that the hardness of cells increased significantly, and the creep flexibility curve decreased significantly under the effect of electric radiation.…”

“… E = σ/ε, the ratio of stress to strain. [ 7 , 17 , 18 , 38 , 39 , 43 , 48 , 69 , 70 , 105 , 106 , 107 , 123 , 125 , 126 , 133 , 134 , 139 , 140 , 141 , 142 , 143 , 149 , 152 , 155 ] Shear modulus (G) Shear stress characterizes the material’s ability to resist shear strain. G = τ/γ, the ratio of shear stress to shear strain.…”

Mechanical Studies of the Third Dimension in Cancer: From 2D to 3D Model

“…The studies of mechanics in 3D systems for cancer research have enabled researchers to develop better technologies and adapt protocols from material science to cancer biology. So far, at a cellular level, mechanics can be measured with different methods probing stiffness at the nano-scale and micro-scale, including micropipette aspiration [ 57 , 58 , 59 ] and optical stretcher [ 60 ] for measuring mechanics of whole cells in suspensions, and atomic force microscopy (AFM) for the investigation of single adherent cells [ 61 , 62 , 63 , 64 ]. For example, many studies used AFM on different types of epithelial cancer cells, showing that cancer cells are generally softer and display lower intrinsic variability in cell stiffness than non-malignant cells [ 65 , 66 ].…”

Finite Element Simulations of Mechanical Behaviour of Endothelial Cells

“…For our research, the following testing methods are most relevant: microplate stretcher [ 10 ], microplate manipulation [ 11 , 12 ], and atomic force microscopy (AFM) [ 13 ]. There are other more recent techniques which can reveal the mechanical characteristics of cells such as a microfluidic device [ 14 ], dissipative particle dynamics [ 15 ], or micropipette aspiration [ 16 , 17 ].…”