Abstract
Purpose :
Cigarette smoking is one of the strongest and most consistent risk factor for age-related macular degeneration (AMD), which retinal pigment epithelial (RPE) cell loss is the key pathophysiological mechanism. This study aimed to investigate the effect of nicotine, a major constituent in the cigarette smoke, and its metabolite, cotinine, on the survival, migration and angiogenic factor secretion properties of human RPE cell line (ARPE-19).
Methods :
ARPE-19 cells were treated with 1 or 2 µM nicotine and/or cotinine continuously for 7 days. Cell viability was evaluated by the MTT assay, whereas cell migration was assessed by the wound scratch assay. The cell integrity of nicotine and cotinine-treated RPE cells was examined by the immunofluorescence analysis of tight junction marker, ZO-1. Angiogenic factor secretion by the nicotine and/or cotinine-treated cells was determined using a multiplex chemiluminescent ELISA kit. Mean of the triplicated experiments from the treated group was compared to that from the vehicle control group.
Results :
The integrity of RPE cells was not altered with the continuous treatment of nicotine and cotinine as shown by the immunofluorescence analysis of ZO-1. Both nicotine and cotinine treatment showed significant reduction in RPE cell viability from 9 – 30% (p < 0.05), compared to the vehicle control at Day 7. Moreover, both nicotine and cotinine would also attenuate the migration properties of RPE cells by 14 – 38% (p < 0.05). In addition, cotinine treatment, but not nicotine, significantly demonstrated lower vascular endothelial growth factor (VEGF) secretion of RPE cells by 2.45 folds (p < 0.001), compared to the control group.
Conclusions :
Continuous exposure of physiological level of nicotine and cotinine alters human RPE cell viability, migration and VEGF secretion properties.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.