PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 4469696

Decrease in free cystine content of cultured cystinotic fibroblasts by ascorbic acid.

W A Kroll·J A Schneider
View original source ↗Export metadata ↓

Abstract

The 100-fold increase in free cystine content characteristic of cultured skin fibroblasts from patients with nephropathic cystinosis was decreased more than 50 percent by addition of L-ascorbic acid to the culture medium at concentrations of 0.29 to 2.9 millimolar. Fresh ascorbic acid must be added to the culture medium daily to produce a progressive decrease of the free cystine content of the cells over a 3-day period. Upon removal of ascorbic acid from the medium, the free cystine content returns to its initial value.

Explore related subjects

Ascorbic AcidCells, CulturedCystineCystinosisDithiothreitolJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

W A Kroll, J A Schneider. 1974-12-13. Decrease in free cystine content of cultured cystinotic fibroblasts by ascorbic acid.. https://doi.org/10.1126/science.186.4168.1040

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2024

Effect of light on ascorbic acid biosynthesis and bioinformatics analysis of related genes in Chinese chives.

Ascorbic acid (AsA) is an essential nutritional component and powerful antioxidant in vegetables, and in plants, AsA levels are regulated by light. AsA levels in the leaves of Chinese chive (Allium tuberosum Rottler ex Spr), a popular vegetable, are poorly understood. Thus, this study was performed to assess the influence of light on AsA biosynthesis in chive and select related genes (AtuGGP1 and AtuGME1); in addition, bioinformatic analyses and gene expression level assays were performed. The biological information obtained for AtuGGP1 and AtuGME1 was analysed with several tools, including NCBI, DNAMAN, and MEGA11. After different light treatments were performed, the Chive AsA content and AtuGGP1 and AtuGME1 expression levels were determined. These results suggest that 1) compared with natural light, continuous darkness inhibited AsA synthesis in chives. 2) The amino acid sequences of AtuGGP1 and AtuGME1 are very similar to those of other plants. 3) The trends observed for the expression levels of AtuGGP1 and AtuGME1 were consistent with the AsA content observed in chives. Hence, we speculated that light controls AsA biosynthesis in chives by regulating AtuGGP1 and AtuGME1 expression. This study provided impactful and informative evidence regarding the functions of GGP and GME in chives.

Ascorbic Acid↗
PubMed1992

Human gastric carcinogenesis: a multistep and multifactorial process--First American Cancer Society Award Lecture on Cancer Epidemiology and Prevention.

Evidence from pathology and epidemiology studies has been provided for a human model of gastric carcinogenesis with the following sequential stages: chronic gastritis; atrophy; intestinal metaplasia; and dysplasia. The initial stages of gastritis and atrophy have been linked to excessive salt intake and infection with Helicobacter pylori. The intermediate stages have been associated with the ingestion of ascorbic acid and nitrate, determinants of intragastric nitrosation. The final stages have been linked with the supply of beta-carotene and with excessive salt intake. Nitrosating agents are candidate carcinogens and could originate in the gastric cavity or in the inflammatory infiltrate.

Ascorbic Acid↗
PubMed1992

Evidence for free radical formation during horseradish peroxidase-catalyzed N-demethylation of crystal violet.

Crystal violet (gentian violet) can undergo an oxidative metabolism, catalyzed by horseradish peroxidase, resulting in formaldehyde formation. The N-demethylation reaction was strongly inhibited by reduced glutathione. Evidence for the formation of a crystal violet radical during the horseradish peroxidase catalyzed reaction was the detection of thiyl and ascorbate radicals from glutathione and ascorbate, respectively. The concentration of radicals from both compounds was significantly increased in the presence of crystal violet. Oxygen uptake was stimulated when glutathione was present in the system and this oxygen uptake was dependent on the dye and enzyme concentration. Oxygen uptake did not occur when ascorbate, instead of glutathione, was present in the system. However, when glutathione was present, ascorbate totally inhibited the glutathione-stimulated oxygen uptake in the crystal violet/horseradish peroxidase/hydrogen peroxide system. Although a weak ESR spectrum from a crystal violet-derived free radical was detected when the dye reacted with H2O2 and horseradish peroxidase, using the fast flow technique, this spectrum could not be interpreted.

Ascorbic Acid↗