Ascorbate deficiency results in decreased collagen production: under-hydroxylation of proline leads to increased intracellular degradation. Academic Article uri icon

Overview

MeSH

  • Ascorbic Acid
  • Cells, Cultured
  • Fibroblasts
  • Humans
  • Hydroxyproline
  • Kinetics

MeSH Major

  • Ascorbic Acid Deficiency
  • Collagen
  • Lung
  • Proline

abstract

  • Collagen production by cultured human lung fibroblasts was examined when the cells were made deficient in ascorbate. Cells grown in the absence of ascorbate produced 30% less collagen during a 6-h labeling period than cells incubated with as little as 1 microgram/ml ascorbate during the labeling period. Cells grown without ascorbate produced under-hydroxylated collagen which was subject to increased intracellular degradation from a basal level of 16% to an enhanced level of 49% of all newly synthesized collagen. The likely mechanism for increased intracellular degradation is the inability of under-hydroxylated collagen to assume a triple-helical conformation causing it to be susceptible to intracellular degradation. Measurement of collagen production by enzyme linked immunoassay (ELISA) using antibodies directed against triple-helical determinants of collagen showed that both types I and III collagens were affected. In contrast, another connective tissue component, fibronectin, was not affected. Analysis by ELISA showed a greater decrease in collagen production than did analysis by the collagenase method, suggesting that some non-helical collagen chains (detected by collagenase but not by ELISA) were secreted in the absence of ascorbate. These results provide a mechanism to account, in part, for the deficiency of collagen in connective tissues which occurs in a state of ascorbate deficiency.

publication date

  • October 15, 1983

has subject area

  • Ascorbic Acid
  • Ascorbic Acid Deficiency
  • Cells, Cultured
  • Collagen
  • Fibroblasts
  • Humans
  • Hydroxyproline
  • Kinetics
  • Lung
  • Proline

Research

keywords

  • Journal Article

Identity

Language

  • eng

PubMed ID

  • 6639074

Additional Document Info

start page

  • 681

end page

  • 686

volume

  • 226

number

  • 2