|Cancer||Cell death||Cell cycle||Cytoskeleton||Exo/endocytosis||Differentiation||Division||Organelles||Signalling||Stem cells||Trafficking|
Inhibitory effects of Vitamin E on UVB-induced apoptosis of chicken embryonic fibroblasts
Dapeng P Jin*†, Chunying Li‡1, Yimei Cong*, Hongjian Yang†, Wenxiu X Zhang*, Weijun Guan*2 and Yuehui Ma*
*Institute of Animal Sciences, Chinese Academy of Agricultural Sciences CAAS, Beijing 100193, Peoples Republic of China, †College of Biological Sciences, China Agricultural University CAU, Beijing 100193, Peoples Republic of China, and ‡Northeast Forestry University NFU, Harbin 150040, Heilongjiang, Peoples Republic of China
Apoptosis research has been focused on several model species in the past decades, whereas studies concerned with non-mammalian vertebrate, particularly birds, have rarely been involved. In accord with requirements to expand the biodiversity of apoptotic research, a chicken embryonic fibroblasts model involving UVB (ultraviolet B) as the death stimulus was established through primary explantation and serial passage. Myriads of antioxidants can inhibit UVB-induced apoptosis by virtue of scavenging reactive oxygen species. To improve our understanding of the possible anti-apoptotic effects and mechanisms of Vitamin E against UVB-induced apoptosis in chicken embryonic fibroblasts, cells treated with Vitamin E after UVB irradiation were stained with AO/EB and Fluo-3/AM to visualize chromatin distribution and calcium homoeostasis, respectively. They were also analysed by flow cytometry to detect mitochondrial transmembrane potential, and cell cycle progression and apoptotic rates were recorded. RT-PCR was used to analyse the expression of some apoptosis-related genes. Typical apoptotic events, including cell shrinkage, blebbing and nuclear condensation, occurred after radiation. In the presence of Vitamin E following irradiation, apoptotic cells were reduced. Ca2+ release was temporarily prevented, and cell cycle arrest at S/G2 checkpoint had almost completely reverted to normal. fas decreased, while procaspase-3 remained nearly unchanged with and without Vitamin E, and bcl2/bax ratio was up-regulated, indicating possible anti-apoptotic mechanisms through the mitochondrial pathway. This new investigation of an apoptosis model involving chicken embryonic fibroblasts expands the database of knowledge across a wider spectrum of vertebrate species.
Key words: apoptotic model, Beijing fatty chicken, Ca2+, embryonic fibroblast line, ultraviolet light, Vitamin E
Abbreviations: [Ca2+](i), free Ca2+, DISC, death-inducing signal complex, PDT population doubling time,, TUNEL, terminal deoxynucleotidyl transferase dUTP nick-end labelling, UVB, ultraviolet B
1Dapeng P. Jin and Chunying Li contributed equally to this work.
2To whom correspondence should be addressed (email email@example.com).
Received 9 October 2009/12 July 2010; accepted 5 November 2010
Published as Cell Biology International Immediate Publication 5 November 2010, doi:10.1042/CBI20090285
© The Author(s) Journal compilation © 2011 Portland Press Limited