Cookies

We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Department of Biosciences

Profile

Publication details for Prof Roy Andrew Quinlan

Markiewicz, Ewa, Barnard, Stephen, Haines, Jackie, Coster, Margaret, Geel, Orry van, Wu, Weiju, Richards, Shane, Ainsbury, Elizabeth, Rothkamm, Kai, Bouffler, Simon & Quinlan, Roy A. (2015). Nonlinear ionizing radiation-induced changes in eye lens cell proliferation, cyclin D1 expression and lens shape. Open biology 5: 150011.

Author(s) from Durham

Abstract

Elevated cataract risk after radiation exposure was established soon after the
discovery of X-rays in 1895. Today, increased cataract incidence among medical
imaging practitioners and after nuclear incidents has highlighted how little is
still understood about the biological responses of the lens to low-dose ionizing
radiation (IR). Here, we show for the first time that in mice, lens epithelial cells
(LECs) in the central region repair DNA double strand breaks (DSB) after
exposure to 20 and 100 mGy more slowly compared with circulating blood lymphocytes,
as demonstrated by counts of gH2AX foci in cell nuclei. LECs in the
central region repaired DSBs faster than either LECs in the lens periphery or
lymphocytes. Although DSB markers (gH2AX, 53BP1 and RAD51) in both lens
regions showed linear dose responses at the 1 h timepoint, nonlinear responses
were observed in lenses for EdU (5-ethynyl-20-deoxy-uridine) incorporation,
cyclin D1 staining and cell density after 24 h at 100 and 250 mGy. After 10
months, the lens aspect ratio was also altered, an indicator of the consequences
of the altered cell proliferation and cell density changes. A best-fit model demonstrated
a dose-response peak at 500 mGy. These data identify specific nonlinear
biological responses to low (less than 1000 mGy) dose IR-induced DNA
damage in the lens epithelium.