alexa Interleukin-6 protects retinal ganglion cells from pressure-induced death.
Ophthalmology

Ophthalmology

Journal of Clinical & Experimental Ophthalmology

Author(s): Sappington RM, Chan M, Calkins DJ

Abstract Share this page

Abstract PURPOSE: The response of retinal ganglion cells (RGCs) to ocular pressure in glaucoma likely involves signals from astrocytes and microglia. How glia-derived factors influence RGC survival at ambient and elevated pressure and whether the inflammatory cytokine interleukin-6 (IL-6) is a contributing factor were investigated. METHODS: Primary cultures of retinal astrocytes, microglia, and RGCs were prepared using immunomagnetic separation. Comparisons were made of RGC survival at ambient and elevated pressure (+70 mm Hg) and with pressure-conditioned medium from glia with, and depleted of, IL-6. RESULTS: Pressure elevated for 24 to 48 hours reduced RGC density, increased TUNEL labeling, and upregulated several apoptotic genes, including the early immediate genes c-jun and jun-B. Pressure-conditioned medium from astrocytes reduced RGC survival another 38\%, while microglia medium returned RGC survival to ambient levels. These effects were unrelated to IL-6 in microglia medium. Neither astrocyte- nor microglia-conditioned medium affected ambient RGC survival unless depleted of IL-6, which induced a 63\% and a 18\% decrease in RGCs, respectively. Recombinant IL-6 equivalent to levels in glia-conditioned medium doubled RGC survival at elevated pressure. CONCLUSIONS: For RGCs at ambient pressure, IL-6 secreted from astrocytes and microglia under pressure is adequate to abate other proapoptotic signals from these glia. For RGCs challenged by elevated pressure, decreased IL-6 in astrocyte medium is insufficient to counteract these signals. Increased IL-6 in microglia medium counters not only proapoptotic signals from these cells but also the pressure-induced apoptotic cascade intrinsic to RGCs. This article was published in Invest Ophthalmol Vis Sci and referenced in Journal of Clinical & Experimental Ophthalmology

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords