Hypoxic conditions decrease the mRNA expression of proalpha1(I) and (III) collagens and increase matrix metalloproteinases-1 of dermal fibroblasts in three-dimensional cultures.

M Yamanaka; O Ishikawa

doi:10.1016/s0923-1811(00)00086-4

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Hypoxic conditions decrease the mRNA expression of proalpha1(I) and (III) collagens and increase matrix metalloproteinases-1 of dermal fibroblasts in three-dimensional cultures.

M Yamanaka·O Ishikawa

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Abstract

The effect of hypoxia on the expression of extracellular matrix-related genes by human dermal fibroblasts was investigated using a novel three-dimensional culture supplemented with L-ascorbic acid 2-phosphate. Experiments were performed by placing replicate dishes in either hypoxic (2%) or in normoxic (20%) condition for various periods of time ranging up to 72 h. The mRNA expression levels of proalpha1(I), proalpha1(III) collagens and MMP-1 were analyzed using Northern blotting. Hypoxia transiently increased proalpha1(I) and proalpha1(III) collagen gene expression at 24 h, but a prolonged exposure to hypoxia decreased them. A slight increase in MMP-1 mRNA was observed at 24 h and prolonged exposure for up 72 h resulted in significantly increased expression of MMP-1 gene. Our results suggest that enhanced degradation as well as decreased synthesis of collagens induced by hypoxia may account for the delayed wound healing associated with circulatory disturbances.

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Actins Cells, Cultured Cytological Techniques Fibroblasts Glyceraldehyde-3-Phosphate Dehydrogenases Humans Hypoxia Matrix Metalloproteinase 1 Procollagen RNA, Messenger Skin Journal Article Research Support, Non-U.S. Gov't

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M Yamanaka, O Ishikawa. 2000. Hypoxic conditions decrease the mRNA expression of proalpha1(I) and (III) collagens and increase matrix metalloproteinases-1 of dermal fibroblasts in three-dimensional cultures.. https://doi.org/10.1016/s0923-1811(00)00086-4

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