The effect of phacoemulsification energy on the redox state of cultured human corneal endothelial cells.
OBJECTIVE
To evaluate the effects of phacoemulsification energy on the redox state and mitochondrial distribution of cultured human endothelial cells.


METHODS
Human corneal endothelial cells from fresh banked human donor tissue not suitable for transplantation were harvested and cultured. Cellular autofluorescence images were obtained using an inverted microscope. The redox fluorometric ratio, which can be related to oxidative stress, was calculated as the net value of fluorescence from the 4,6-diamidino-2-phenylindole channel divided by the net value of fluorescence from the fluorescein isothiocyanate-conjugated channel after subtraction of background. For determining the mitochondrial distribution patterns, the cell area was divided by drawing a line halfway between the nuclear and cell membranes. The average fluorescence in the central area was divided by the average fluorescence in the peripheral area. This ratio was compared.


RESULTS
Human corneal endothelial cells exposed to increasing phacoemulsification times and increasing ultrasonic energy levels displayed dose-dependent decreases in measured redox ratios. Lower redox ratios in response to phacoemulsification did not associate with decreases in cell size or altered patterns of mitochondrial localization.


CONCLUSIONS
Redox fluorometry may serve as a useful indicator for the in vitro study of human corneal endothelial cell physiological response to ultrasonic stressors and potentially other nonoxidative stressors.


CONCLUSIONS
Redox fluorometry in combination with human corneal endothelial cell morphometric measurements has potential to serve as an indicator of human corneal endothelial cell injury resulting secondary to ultrasound phacoemulsification.
Department of Ophthalmology, Johns Hopkins University, Baltimore, Maryland 21287, USA.
Young Joo
YJ
Shin
Yutaro
Y
Nishi
Christoph
C
Engler
Joann
J
Kang
Sarah
S
Hashmi
Albert S
AS
Jun
Peter L
PL
Gehlbach
Roy S
RS
Chuck
D048429:Cell Size; D002470:Cell Survival; D002478:Cells, Cultured; D004728:Endothelium, Corneal / Q000166:cytology / Q000378:metabolism*; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D005456:Fluorescent Dyes; D015590:Fluorophotometry; D006801:Humans; D007211:Indoles / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000378:metabolism*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D018918:Phacoemulsification
D005456:Fluorescent Dyes; D007211:Indoles; C007293:DAPI; D016650:Fluorescein-5-isothiocyanate