The effect of glucose deprivation on collagen synthesis in fibroblast cultures.
It was decided to study the effect of glucose deprivation on collagen synthesis and degradation in fibroblast cultures and a correlation of these processes with the expression of oxygen/glucose regulated proteins (ORP150/GRP170). The incorporation of radiolabeled proline into collagenase-sensitive and hydroxyproline-containing proteins was used as an index of collagen synthesis, whereas pulse-chase technique was employed to evaluate the degradation of newly synthesised proteins. We demonstrated that fibroblasts incubated in high-glucose medium synthesised detectable amounts of collagenous proteins. Most of them were secreted into the culture medium. The shortage of glucose resulted in about 30% reduction in synthesis of collagenous proteins, both those secreted into culture medium and remaining in the cell layer. The pulse-chase experiments demonstrated that the reduced amount of newly synthesised collagen was protected against intracellular degradation. Proportionally less collagen was degraded in cultures incubated in low-glucose than in high-glucose media. These phenomena were accompanied by an increase in the expression of chaperon-ORP150 in cultures growing in low-glucose medium. We suggest that the increased expression of ORP150 is a factor which protects collagen against intracellular degradation induced by glucose deprivation.
Cechowska-Pasko
Marzanna
M
Department of Pharmaceutical Biochemistry, Medical University of Białystok, Mickiewicza 2A, 15-089 Białystok, Poland. mapasko@tlen.pl
Surazyński
Arkadiusz
A
Bańkowski
Edward
E
D003094:Collagen / Q000096:biosynthesis*; D005347:Fibroblasts / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins; D006801:Humans; D011506:Proteins / Q000378:metabolism; D013997:Time Factors
D018840:HSP70 Heat-Shock Proteins; D011506:Proteins; C050087:oxygen-regulated proteins; D003094:Collagen; D005947:Glucose