Promotion of cystine uptake, increase of glutathione biosynthesis, and modulation of glutathione status by S-2-(3-aminopropylamino)ethyl phosphorothioic acid (WR-2721) in Chinese hamster cells

Journal Article · Sat Apr 15 00:00:00 EDT 1989 · Cancer Res.; (United States)

OSTI ID:5991532

Issels, R D; Nagele, A

We recently found that exposure of cells to different aminothiols promotes cystine uptake and leads to an increase of cellular glutathione by new biosynthesis. Therefore, we further investigated whether the known radioprotective and chemoprotective aminothiol derivative S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) or its dephosphorylated form (WR-1065) will lead to similar effects. In order to convert WR-2721 to the free thiol compound (WR-1065) in vitro, the medium also contained 20 U/ml alkaline phosphatase (AP). For uptake studies a modified McCoy's 5A medium supplemented with 0.1 mM (35S)cystine was used. In Chinese hamster ovary (CHO) and Chinese hamster ovarian carcinoma (OvCa) cells, WR-2721 exposure alone did not increase the cystine uptake relative to that of control (untreated) cells, while WR-2721 + AP enhanced the uptake of cystine more than twofold in both cell lines. The increase of cystine uptake was dependent on the time of exposure (0-60 min) and the concentrations of WR-2721 (0-8 mM) + AP. Half-maximal uptake of cystine was observed at concentrations of 0.69 and 0.57 mM WR-2721 in CHO and OvCa cells, respectively. Determination of both reduced (GSH) and oxidized (GSSG) cellular glutathione levels after the exposure (0-300 min) to WR-2721 + AP in CHO cells showed a depletion of GSH to less than 10% of the pretreatment value and a 4-fold reduction of the GSH/GSSG ratio. In contrast, in OvCa cells the amount of total glutathione rather increased with no significant change of the GSH/GSSG ratio by the exposure to WR-2721 + AP. Further analysis using high-performance liquid chromatography of cell extracts revealed that the relative amount of incorporated (35S)-cystine into glutathione was increased similarly in both cell lines.

• Research Organization: Ludwig-Maximilians-Universitaet Muenchen (West Germany)
• OSTI ID: 5991532
• Journal Information: Cancer Res.; (United States), Vol. 49:8
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CYSTINE
UPTAKE
GLUTATHIONE
BIOSYNTHESIS
ORGANIC PHOSPHORUS COMPOUNDS
BIOLOGICAL EFFECTS
ALKALINE PHOSPHATASE
CELL CULTURES
CHO CELLS
DOSE-RESPONSE RELATIONSHIPS
HAMSTERS
LIQUID COLUMN CHROMATOGRAPHY
SULFUR 35
THIOLS
TIME DEPENDENCE
TRACER TECHNIQUES
TUMOR CELLS
AMINO ACIDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
DISULFIDES
DRUGS
ENZYMES
ESTERASES
EVEN-ODD NUCLEI
HYDROLASES
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MAMMALS
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PEPTIDES
PHOSPHATASES
POLYPEPTIDES
PROTEINS
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
RODENTS
SEPARATION PROCESSES
SULFUR ISOTOPES
SYNTHESIS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques