|
KMID : 0578319960060060659
|
|
Molecules and Cells
1996 Volume.6 No. 6 p.659 ~ p.665
|
|
|
Inductions of Keratins, bcl-2 ad p53 in Human Epidermal Raft culture upon UV-B irradiation Were Dependent on UV-B Doses and Post-irradiation time
|
|
Son, Young sook
Lee, Ji Yong/Yi, Jae youn/Hong, Seok-Il/Youn, Jai Il/Cho, Kwang Hyun
|
|
|
Abstract
|
|
|
|
We reprort here that the stratified human epidermis regenerated in vitro by raft culture can reproduce most of the UV-B mediated biological responses of in vivo skin, and furthermore those responses are highly dependent on UV-B doses and post-irradiation time. Kertains are one of the most susceptible biomolecules for UV-B irradiation on the skin. Biosynthesis of all keratins in the intermediate filament preparation was diminished for the first 16 h post-irradiation, of which K1 and K13 were most prominently inhibited. During the biosynthetic labeling period from 24 h to 40 h post-irradiation, all keratins except K13 were stimulated in the 10 and 20 mj/cm² irradiated but still suppressed in the 30 mj/cm² irradiated. The strongest K1 and K6 inductions were observed in the 20 mj/cm² irradiated. Immunocytochemical staining of the raft sections with anti-K1 antibody revealed that the K1 negative suprabasal cell layer became greater at 40 h post-irradiation in the 30 mj/cm² irradiated. For the estimation of the apoptotic progression in the UV-B irradiated raft culture, bcl-2 biosynthesis and p53 induction were also examined at a different post-irradiarion time. Bcl-2 biosynthesis was almost undetectable before or immediately after UV-B irradiation. But a new synthesis of bcl-2 was markedly elevated during the labeling period from 24 h to 40 h post-irradiation in the 10 mj/cm² irradiated, much less in the 20 mj/cm² irradiated, and none in the 30 mj/cm² irradiated. Based on immunocytochemical staining, basal cells accumulated p53 protein in the nucleus at 16 h post-irradiation in a UV-B dose-dependent manner. In the 30 mj/cm² irradiated, all the basal cells were positive in p53 staining. However at 40 h post irradiation, p53 staining disappeared in most basal cells of the 10 or 20 mj/cm² irradiated raft culture but persistant accumulation of p53 protein was still observed in the 30 mj/cm² irradiated, which is well correlated with the lack of bcl-2 and keratin induction at this dose. Therefore inductions or suppressions of K1, K6, K13, bcl-2, and p53 in response to UV-B irradiation were specific to the UV-B doses and post-irradiation time. The results in this study using the raft culture system may be applied in the future as useful biomarkers for the estimation of UV-B mediated epidermal damage as well as for the evaluation of UV-protection agents on the skin.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
  
|
|