TY - JOUR PY - 2014// TI - Early detection of subclinical visual damage after blast-mediated TBI enables prevention of chronic visual deficit by treatment with P7C3-S243 JO - Investigative ophthalmology and visual science A1 - Dutca, Laura A1 - Stasheff, Steven F. A1 - Hedberg-Buenz, Adam A1 - Rudd, Danielle S. A1 - Batra, Nikhil A1 - Blodi, Frederick R. A1 - Yorek, Matthew S. A1 - Yin, Terry A1 - Shankar, Malini A1 - Herlein, Judith A1 - Naidoo, Jacinth A1 - Morlock, Lorraine A1 - Williams, Noelle A1 - Kardon, Randy H. A1 - Anderson, Michael A1 - Pieper, Andrew A1 - Harper, Matthew M. SP - 8330 EP - 8341 VL - 55 IS - 12 N2 - PURPOSE: TBI frequently leads to visual dysfunction. The purpose of this study was to investigate the effect of TBI on RGCs, and to test whether treatment with the novel neuroprotective compound P7C3-S243 could prevent functional deficits in the visual system.

METHODS: Blast-mediated TBI was induced in a blast chamber. RGC physiology was evaluated using a multi-electrode array and pattern electroretinogram (PERG). Analysis of RGC dendritic field and number were evaluated at the end of the study. Visual outcome measures were also evaluated based on treatment of mice with P7C3-S243 or vehicle control.

RESULTS Deficits in PERG after TBI occur in a temporally bimodal fashion, with temporary recovery 4 weeks after injury followed by chronically persistent dysfunction 12 weeks later. This later time point is associated with dendritic abnormalities and death of RGCs. We also demonstrate that ongoing pathologic processes during the temporary recovery latent period (including abnormalities of RGC physiology) lead to future dysfunction of the visual system. We report that modification of PERG to provocative postural tilt testing elicits changes in PERG measurements that correlate with a key in vitro measures of damage: the spontaneous and light-evoked activity of RGCs.

CONCLUSIONS: Provocative PERG testing serves as a non-invasive test in the living organism to identify early damage to the visual system, which may reflect corresponding damage in the brain that is not otherwise detectable by noninvasive means. Treatment with P7C3-S243 immediately after injury and throughout the temporary recovery latent period protects mice from developing chronic visual system dysfunction.

Language: en

LA - en SN - 0146-0404 UR - http://dx.doi.org/10.1167/iovs.14-15468 ID - ref1 ER -