July 2019
Volume 60, Issue 9
Open Access
ARVO Annual Meeting Abstract  |   July 2019
Assessing the Effects of Exogenous Cholesterol Metabolites on Human Optic Nerve Stiffness with Atomic Force Microscopy
Author Affiliations & Notes
  • Gurkaran Singh Sarohia
    University of British Columbia, Prince George, British Columbia, Canada
  • Wyndham More Batchelor
    University of Miami, Miami, Florida, United States
  • Erik D Garza
    University of Miami, Miami, Florida, United States
  • Nicholas DiStefano
    University of Miami, Miami, Florida, United States
  • Noel Marysa Ziebarth
    University of Miami, Miami, Florida, United States
  • Sanjoy K Bhattacharya
    University of Miami, Miami, Florida, United States
  • Footnotes
    Commercial Relationships   Gurkaran Sarohia, None; Wyndham Batchelor, None; Erik Garza, None; Nicholas DiStefano, None; Noel Ziebarth, Carl Zeiss Meditec (C); Sanjoy Bhattacharya, None
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science July 2019, Vol.60, 3787. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Gurkaran Singh Sarohia, Wyndham More Batchelor, Erik D Garza, Nicholas DiStefano, Noel Marysa Ziebarth, Sanjoy K Bhattacharya; Assessing the Effects of Exogenous Cholesterol Metabolites on Human Optic Nerve Stiffness with Atomic Force Microscopy. Invest. Ophthalmol. Vis. Sci. 2019;60(9):3787.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : To assess changes in the elasticity of ex vivo human optic nerve tissue due to exogenous addition of various cholesterol species, including esterified cholesterol, using atomic force microscopy (AFM).

Methods : Optic nerve tissue (total n=25) was procured from human cadaveric donor eyes (with equal gender distribution, donor age average 70.5 ± 6.5 year, all Caucasian donors) with no known history of ocular diseases. Optic nerves were transversely sectioned, and these sections were secured to the bottom of the petri dish using a topical “liquid bandage” formulation (CVS Health); the tissue was then immersed in PBS to maintain hydration. Young’s Modulus was determined using a custom designed AFM through microindentation (2mm diameter spherical tip, 0.1N/m spring constant). Force-indentation curves were acquired from measurements and analyzed using custom MATLAB code. Young’s modulus of elasticity was determined using the Hertz model for a spherical indenter. Measurements were repeated up to 15 times at 3 different points. For each sample, elasticity was assessed prior to and immediately after a 15-minute treatment period. Tissue sections were treated with 5 µM lipids (Cholesterol Ester (20:3), Cholesterol, Zymosterol, and 15-alpha-hydroxycholestane), or phosphate buffered saline (PBS) as a control for 15 minutes. The results were normalized using the average elastic modulus values from each experiment and a two-tailed t-test was performed.

Results : All samples had a significantly different (p<0.05, n=5) Young’s modulus of elasticity pre- and post-treatment with exogenous lipids (Cholesterol Ester (20:3), Cholesterol, Zymosterol, and 15-alpha-hydroxycholestane). There was no significant difference for the samples treated with PBS control. There was an increase in Young’s modulus (increase in stiffness) for cholesterol (154%), Zymosterol (190%), 15-alpha-hydroxycholestane (30%) and a decrease in Young’s modulus (decrease in stiffness) for Cholesterol Ester (56%).

Conclusions : Our results suggest that cholesterol and its precursors such as Zymosterol and 15-alpha-hydroxycholestane increase the stiffness of the optic nerve, whereas unsaturated Cholesterol Ester (20:3) decreases its stiffness.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×