Lens Epithelial Apoptosis and Cell Proliferation in Human Age-Related Cortical Cataract

Abstract

The epithelium of human lenses with cortical cataract undergoes low rate apoptotic death. This limited epithelial apoptosis is unlikely to result in any significant cell density decrease since epithelial gaps are likely to be replaced by cell proliferation at the germinative zone of the anterior lens capsule. Nevertheless, the accumulation of small-scale epithelial losses during lifetime may induce alterations in lens fiber formation and homeostasis and result in loss of lens transparency.

Trypan blue staining for capsulorhexis: Ultrastructural effect on lens epithelial cells and capsules

“…We observed that trypan blue toxicity changed LEC morphology and found evidence of 2 pathways of cell death, apoptosis and autophagy. Although apoptosis has been described in studies of LECs from regular senile cataract surgery, 21 to our knowledge our study is the first to analyze the ability of trypan blue to induce apoptosis in LECs. Our immunohistochemical study showing the presence of beclin-1, a marker of cell death by autophagy, also appears to be a unique finding, further supporting that trypan blue-assisted capsulorhexis causes damage to the remaining lens cells.…”

Programmed cell death in intervertebral disc degeneration

“…PCD is extensively involved in embryonic development and various physiological and pathological processes in multicellular organisms. There are evidences indicating that PCD plays an important role in some human degenerative diseases such as Alzheimer's disease [20][21][22], senile cataract [23][24][25], osteoarthritis [26][27][28][29], and so on. PCD in human IVD was initially reported in 1998 by Gruber et al [30] and it has become a new research area of interest in recent years, with suggestions that it is a crucial event in IVD degeneration.…”

Activity of superoxide dismutase isoenzymes in lens epithelial cells derived from different types of age-related cataract

“…This limited epithelial apoptosis is unlikely to result in a significant decrease in cell density because epithelial gaps are likely to be replaced by cell proliferation in the germinative zone of the anterior lens capsule. 21 We believe that the replacement of epithelial cells by cell proliferation in the epithelial gaps maintains cell density in cortical cataracts, which in turn may play a crucial role in the production of an increased level of SOD to counteract the elevated level of oxidative stress.…”