Effects of GSK101 Exposure on Astrocyte Mechanical Properties, Collagen Production, and Viability

Author

Ethan EcholsFollow

Date of Graduation

5-2018

Document Type

Thesis

Degree Name

Bachelor of Science in Biomedical Engineering

Degree Level

Undergraduate

Department

Biomedical Engineering

Advisor/Mentor

Wolchok, Jeffrey

Abstract

Transient receptor potential vanilloid 4 (TRPV4) is a cation channel protein which is thought to facilitate extracellular matrix (ECM) modification and glial scar formation following traumatic brain injury (TBI). Activation of TRPV4 has been shown to correlate with an increase in intracellular Ca²⁺ concentration. TRPV4 is subject to both chemical and mechanical activation. This study involved chemical activation of TRPV4 in cultured mouse astrocytes using GSK101, the primary agonist of TRPV4, and subsequent evaluation of mechanical and chemical changes to the ECM. Prior to GSK101 exposure, the cells were seeded into Matrigel Matrix, a gelatinous protein mixture intended to simulate a natural 3D environment for cell growth. Cells assigned to the experimental treatment group were regularly exposed to a known concentration of GSK101, while cells assigned to the control treatment group were exposed to an equivalent volumetric concentration of dimethyl sulfoxide (DMSO) accordingly. Following treatment, rheological testing was used to assess changes in the mechanical properties of each sample through application of shear stress. Following this, additional Matrigel samples were produced and treated. Each of these samples was lyophilized and hydrolyzed. The hydroxyproline assay was then used to quantify the presence of collagen, a major component of ECM, in each sample. Although the hydroxyproline assay revealed no statistically significant difference in collagen content between experimental and control samples, rheological testing revealed experimental samples to exhibit a greater storage modulus than control samples. The effects of mouse astrocyte exposure to DMSO and varying concentrations of GSK101 on cell viability were also assessed. While both exposure to high concentrations of pure DMSO and exposure to high concentrations of GSK101 suspended in DMSO were shown to reduce cell viability, there is no evidence to suggest that GSK101 alone affects cell viability.

Citation

Echols, E. (2018). Effects of GSK101 Exposure on Astrocyte Mechanical Properties, Collagen Production, and Viability. Biomedical Engineering Undergraduate Honors Theses Retrieved from https://scholarworks.uark.edu/bmeguht/56