scholarly journals Studies on the differential inhibition of glutathione conjugate formation of (+)-anti-benzo[a]pyrene 7,8-dihydrodiol 9,10-epoxide and 1-chloro-2,4-dinitrobenzene in V79 Chinese hamster cells

2000 ◽  
Vol 349 (3) ◽  
pp. 693-696 ◽  
Author(s):  
Kathrin SUNDBERG ◽  
Bengt JERNSTRÖM ◽  
Stellan SWEDMARK
Keyword(s):  
Molecular Mass ◽  
Glutathione Transferase ◽  
Chinese Hamster ◽  
Cell Extract ◽  
Differential Inhibition ◽  
V79 Cells ◽  
Chinese Hamster Cells ◽  
Carcinogenic Compound ◽  
V79 Cell ◽  
Mcf 7

V79 Chinese hamster cells have previously been shown to lack the capacity to detoxify the mutagenic and carcinogenic compound (+)-anti-benzo[a]pyrene 7,8-dihydrodiol 9,10-epoxide [(+)-anti-BPDE] by Pi class glutathione transferase (GSTPi)-catalysed conjugation with GSH, although these cells contain such an enzyme [Romert, Dock, Jenssen and Jernström (1989) Carcinogenesis 10, 1701–1707; Swedmark, Romert, Morgenstern and Jenssen (1992) Carcinogenesis 13, 1719–1723; Swedmark and Jenssen (1994) Gene 139, 251–256]. Previous findings also indicate that these results do not depend on an inactive GSTPi enzyme, since V79 cells conjugate 1-chloro-2,4-dinitrobenzene (CDNB) with GSH, but more likely on (a) factor(s) that inhibit(s) V79 GSTPi selectively [Swedmark, Jernström and Jenssen (1996) Biochem. J. 318, 533–538]. The present study demonstrates that both human and V79 recombinant GSTPi enzymes are inhibited with respect to conjugating (+)-anti-BPDE, but not CDNB, after pre-incubation with V79-cell extract, but not with MCF-7-cell extract. In addition, it was found that the inhibition is dependent on the amount of cell extract present and that the factor(s) is heat-resistant and has a molecular mass of less than 10 kDa, suggesting that the factor(s) is (are) non-proteinaceous in nature.

Bioactivation and Toxicity of Two Anthraquinones in V79 Chinese Hamster Cells

1991 ◽  
Vol 19 (1) ◽  
pp. 48-52
Author(s):  
Maurizio Mian ◽  
Duccio Fratta ◽  
Giuseppe Rainaldi ◽  
Dino Benetti ◽  
Pier Giovanni Gervasi
Keyword(s):  
Cytochrome P450 ◽  
Nadh Dehydrogenase ◽  
Chinese Hamster ◽  
Cytochrome P450 Reductase ◽  
V79 Cells ◽  
Chinese Hamster Cells ◽  
P450 Reductase ◽  
Nadph Cytochrome P450 Reductase ◽  
Dt Diaphorase

The role of the flavoprotein NADPH cytochrome P450 reductase, NADH-dehydrogenase and DT-diaphorase in the biotransformation of the anthraquinones rhein and danthron was investigated using purified enzymes, subcellular fractions and cell cultures. The results demonstrated that rhein was more able than danthron to produce O2 by P450 reductase, NADH-dehydrogenase and V79 homogenate and microsomes, and this may explain its higher toxicity to V79 cells. In addition, unlike other quinones, DT-diaphorase appeared not to play a detoxication role in rhein and danthron biotransformation. On the contrary, by inhibiting DT-diaphorase with dicoumarol, the rhein- and danthron-derived cytotoxicity in V79 cells was reduced. This finding suggests that, for these quinones, other coumarol-sensitive biotransformation routes are operative in V79 cells.

scholarly journals Tyrosyltubulin ligase and colchicine binding activity in synchronized Chinese hamster cells.

1978 ◽  
Vol 78 (2) ◽  
pp. 441-450 ◽  
Author(s):  
G L Forrest ◽  
R R Klevecz
Keyword(s):  
Cell Cycle ◽  
Chinese Hamster ◽  
Binding Activity ◽  
Maximum Activity ◽  
V79 Cells ◽  
Chinese Hamster Cells ◽  
Minor Peak ◽  
A Minor ◽  
Two Peaks ◽  
Potassium Magnesium

Tyrosyltubulin ligase (TTL) was found to be present in CHO and V79 Chinese hamster cells grown in tissue culture. The enzyme is soluble and requires potassium, magnesium, and ATP for maximum activity and requires tubulin as a substrate. TTL was analyzed through the cell cycle of V79 and CHO Chinese hamster cells. The enzyme showed two peaks of activity in V79 cells at 4 h and 7 h after mitotic selection, corresponding to the early S and mid to late S phases of the cell cycle. In CHO cells the enzyme displayed a major peak of activity at mid S and a minor peak or plateau during early S. Tubulin, as measured by (3H)colchicine binding, was shown to increase through S phase and reach a maximum late in the cycle during G2 approx. 3 h after maximum TTL activity.

scholarly journals Proteomics provides insights into the inhibition of Chinese hamster V79 cell proliferation in the deep underground environment

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jifeng Liu ◽  
Tengfei Ma ◽  
Mingzhong Gao ◽  
Yilin Liu ◽  
Jun Liu ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Dose Rate ◽  
Background Radiation ◽  
Chinese Hamster ◽  
Biological Study ◽  
V79 Cells ◽  
Deep Underground ◽  
Γ Ray ◽  
V79 Cell ◽  
Cells Cultured

Abstract As resources in the shallow depths of the earth exhausted, people will spend extended periods of time in the deep underground space. However, little is known about the deep underground environment affecting the health of organisms. Hence, we established both deep underground laboratory (DUGL) and above ground laboratory (AGL) to investigate the effect of environmental factors on organisms. Six environmental parameters were monitored in the DUGL and AGL. Growth curves were recorded and tandem mass tag (TMT) proteomics analysis were performed to explore the proliferative ability and differentially abundant proteins (DAPs) in V79 cells (a cell line widely used in biological study in DUGLs) cultured in the DUGL and AGL. Parallel Reaction Monitoring was conducted to verify the TMT results. γ ray dose rate showed the most detectable difference between the two laboratories, whereby γ ray dose rate was significantly lower in the DUGL compared to the AGL. V79 cell proliferation was slower in the DUGL. Quantitative proteomics detected 980 DAPs (absolute fold change ≥ 1.2, p < 0.05) between V79 cells cultured in the DUGL and AGL. Of these, 576 proteins were up-regulated and 404 proteins were down-regulated in V79 cells cultured in the DUGL. KEGG pathway analysis revealed that seven pathways (e.g. ribosome, RNA transport and oxidative phosphorylation) were significantly enriched. These data suggest that proliferation of V79 cells was inhibited in the DUGL, likely because cells were exposed to reduced background radiation. The apparent changes in the proteome profile may have induced cellular changes that delayed proliferation but enhanced survival, rendering V79 cells adaptable to the changing environment.

scholarly journals Differential activation of the hprt gene on the inactive X chromosome in primary and transformed Chinese hamster cells.

1989 ◽  
Vol 9 (4) ◽  
pp. 1635-1641 ◽  
Author(s):  
S G Grant ◽  
R G Worton
Keyword(s):  
Cell Lines ◽  
X Chromosome ◽  
Gene Activation ◽  
Chinese Hamster ◽  
Fibroblast Cell ◽  
Dna Demethylation ◽  
Hprt Gene ◽  
Primary Fibroblast ◽  
Chinese Hamster Cells ◽  
Inactive X Chromosome

We have investigated the genetic activation of the hprt (hypoxanthine-guanine phosphoribosyltransferase) gene located on the inactive X chromosome in primary and transformed female diploid Chinese hamster cells after treatment with the DNA methylation inhibitor 5-azacytidine (5azaCR). Mutants deficient in HPRT were first selected by growth in 6-thioguanine from two primary fibroblast cell lines and from transformed lines derived from them. These HPRT- mutants were then treated with 5azaCR and plated in HAT (hypoxanthine-methotrexate-thymidine) medium to select for cells that had reexpressed the hprt gene on the inactive X chromosome. Contrary to previous results with primary human cells, 5azaCR was effective in activating the hprt gene in primary Chinese hamster fibroblasts at a low but reproducible frequency of 2 x 10(-6) to 7 x 10(-6). In comparison, the frequency in independently derived transformed lines varied from 1 x 10(-5) to 5 x 10(-3), consistently higher than in the nontransformed cells. This increase remained significant when the difference in growth rates between the primary and transformed lines was taken into account. Treatment with 5azaCR was also found to induce transformation in the primary cell lines but at a low frequency of 4 x 10(-7) to 8 x 10(-7), inconsistent with a two-step model of transformation followed by gene activation to explain the derepression of hprt in primary cells. Thus, these results indicate that upon transformation, the hprt gene on the inactive Chinese hamster X chromosome is rendered more susceptible to action by 5azaCR, consistent with a generalized DNA demethylation associated with the transformation event or with an increase in the instability of an underlying primary mechanism of X inactivation.

The Cytotoxicity of 27 Chemicals to V79 Chinese Hamster Cells

1987 ◽  
Vol 15 (1) ◽  
pp. 30-32
Author(s):  
Michael Garle ◽  
Alison H. Hammond ◽  
Jeffrey R. Fry
Keyword(s):  
Chinese Hamster ◽  
Chinese Hamster Cells
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