Endothelial glycocalyx detection and characterization by means of atomic force spectroscopy: Comparison of various data analysis approaches.

In recent years, atomic force spectroscopy (AFS) has been used to detect and characterize the endothelial glycocalyx (eGlx) in in vitro and ex vivo experiments. Several analysis methods were proposed, which differ not only in the numerical implementations, but also in physical models of glycocalyx description. Therefore, it is difficult to directly relate the experiments performed by different groups.

Metformin attenuates adhesion between cancer and endothelial cells in chronic hyperglycemia by recovery of the endothelial glycocalyx barrier.

Background: Epidemiologic studies suggest that diabetes is associated with an increased risk of cancer. Concurrently, clinical trials have shown that metformin, which is a first-line antidiabetic drug, displays anticancer activity. The underlying mechanisms for these effects are, however, still not well recognized.

AFM-based detection of glycocalyx degradation and endothelial stiffening in the db/db mouse model of diabetes.

Degradation of the glycocalyx and stiffening of endothelium are important pathophysiological components of endothelial dysfunction. However, to our knowledge, these events have not been investigated in tandem in experimental diabetes. Here, the mechanical properties of the glycocalyx and endothelium in ex vivo mouse aorta were determined simultaneously in indentation experiments with an atomic force microscope (AFM) for diabetic db/db and control db/+ mice at ages of 11-19 weeks.

The impact of hyperglycemia on adhesion between endothelial and cancer cells revealed by single-cell force spectroscopy.

The impact of hyperglycemia on adhesion between lung carcinoma cells (A549) and pulmonary human aorta endothelial cells (PHAEC) was studied using the single-cell force spectroscopy. Cancer cells were immobilized on a tipless Atomic Force Microscopy (AFM) cantilever and a single layer of endothelial cells was prepared on a glass slide. The measured force-distance curves provided information about the detachment force and about the frequency of specific ligand-receptor rupture events.

Biocompatible and fluorescent superparamagnetic iron oxide nanoparticles with superior magnetic properties coated with charged polysaccharide derivatives.

Syntheses and characterizations of biocompatible superparamagnetic iron oxide nanoparticles with embedded curcumin and coated with ultrathin layer of hyaluronic acid-curcumin (HA-Cur) conjugate have been reported. Zeta potential measurements confirmed effective coating of native iron oxide nanoparticles stabilized by cationic derivative of chitosan (SPION-CCh) with the synthesized HA-Cur conjugate. Both SPIONs with embedded curcumin and the ones coated with HA-Cur (SPION-CCh/HA-Cur) revealed desired magnetic characteristics while fluorescent properties were much better for the coated nanoparticles.

Morphological and nanomechanical changes in mechanosensitive endothelial cells induced by colloidal AFM probes.

Mechanotransduction is one of the main properties of endothelial cells (ECs) phenotype. Hemodynamic forces like flow-generated endothelial shear stress play a fundamental role in ECs cytoskeletal remodeling and activate signaling cascades in ECs. AFM methods are widely used to characterize morphology as well as mechanical properties of cells.

Nano-mechanical model of endothelial dysfunction for AFM-based diagnostics at the cellular level.

A review of recent experimental investigations on the nanomechanical response of individual endothelial cells to inflammation caused by environmental agents and selected chemical compounds is presented. We focus on the results obtained by means of the force spectroscopy using the tip of an atomic force microscope as an imaging and nanoindentation spectroscopic probe. The findings presented in this review allow validating the nanoindentation method as a tool for quantitative cell elasticity probing and thereby allow proposing a nanomechanical model of endothelial dysfunction that could be practically used for drug efficacy and toxicity profiling in the endothelium at the subcellular level.