Apoptosis is a feature of TGF beta-induced cataract.
BACKGROUND
Studies in our laboratory have shown that transforming growth factor beta (TGF beta) induces rodent lens epithelial cells to undergo aberrant growth and differentiation that reproduces morphological and molecular features of human anterior subcapsular cataract and posterior capsule opacification. In addition, features of apoptosis have been described in some forms of human cataract. In the present study we investigated apoptotic changes induced by TGF beta in our rodent models.


METHODS
Lens epithelial explants and whole lenses from rats were cultured with TGF beta. Morphological analysis and TUNEL were used to detect apoptotic changes. Transgenic mice expressing a self-activating form of human TGF beta 1 in the lens were included in the analysis.


RESULTS
TGF beta-induced cell loss in epithelial explants coincided with increased numbers of pyknotic nuclei. Some of these nuclei were TUNEL-positive. Studies on lenses cultured with TGF beta and lenses from transgenic mice showed that the subcapsular plaques that developed contained pyknotic nuclei and that many of these were TUNEL-positive.


CONCLUSIONS
This study shows that cells develop morphological and molecular features of apoptosis in TGF beta-induced cataract models. This confirms that apoptosis can be included as another TGF beta-induced cellular change that mimics events in human cataract.
Maruno
Kevin A
KA
Department of Anatomy and Histology and Institute for Biomedical Research, University of Sydney, NSW, Australia.
Lovicu
Frank J
FJ
Chamberlain
Coral G
CG
McAvoy
John W
JW
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002386:Cataract / Q000139:chemically induced* / Q000473:pathology*; D002452:Cell Count; D018929:Cell Culture Techniques; D004847:Epithelial Cells / Q000187:drug effects* / Q000473:pathology; D020287:In Situ Nick-End Labeling; D007908:Lens, Crystalline / Q000187:drug effects* / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D009924:Organ Culture Techniques; D051381:Rats; D017208:Rats, Wistar; D016212:Transforming Growth Factor beta / Q000494:pharmacology* / Q000502:physiology; D053773:Transforming Growth Factor beta1
C508960:TGFB1 protein, human; C508961:Tgfb1 protein, mouse; C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1