Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0038187 (starvation)
24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dimethyl sulfoxide (DMSO), a well-known differentiation inducer in several myeloid cells, also induces a reversible G(1) arrest in many cell lines. We recently showed that DMSO induces a G(1) phase arrest in Chinese hamster ovary (CHO) cells, by restoring contact inhibition and preventing high density-dependent apoptosis. CHO cells are frequently used in cell biology and mutagenesis studies due to their good growth capacity and ease of manipulation but are very difficult to synchronize by serum starvation since they detach from monolayers when they reach confluence. In this study we investigated the possibility of using DMSO to reversibly synchronize CHO cells in the G(1) phase of the cell cycle and analysed whether toxic effects follow the arrest using growth curve, sister chromatid exchange and micronuclei assays. We carried out a kinetic analysis of the arrest by DMSO and re-entry into the cell cycle after drug release by cytofluorimetric analysis of DNA content and bromodeoxyuridine incorporation. We show that CHO cells are efficiently and reversibly arrested in G(1) by DMSO in concentrations ranging between 1 and 2%. In our experiments, >90% of cells grown for 96 h in presence of the drug were arrested in G(1) and synchronously re-entered S phase approximately 8-12 h after release. Furthermore, expression levels of p27 were down-regulated during G(1) progression and cyclin D3 and E expression patterns were similar to those observed after serum starvation. No detectable cytotoxicity or genetic damage were induced in G(1) released cells as revealed by the tests employed. Our results show that DMSO is a very powerful inducer of G(1) synchronization in CHO cells without detectable cytotoxic or genetic effects in cell populations released from G(1) arrest. DMSO synchronization represents a model system in which to analyse protein activities regulating G(1) progression and investigate the response of G(1) cells to mutagen treatments.
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PMID:Reversible G(1) arrest by dimethyl sulfoxide as a new method to synchronize Chinese hamster cells. 1220 30

We recently cloned six human importin a proteins that transport specific substrates in complex with importin beta into the nucleus. We now compared their absolute expression levels in different human cell lines. We examined their expression regulation during human cell proliferation and differentiation by means of specific antibodies. Proliferation inhibition by starvation of HeLa and HaCaT cells led to a marked decrease in the expression of various nuclear transport factors. In contrast, re-addition of serum increased alpha-importin expression. We analyzed two models for cell differentiation and found differential importin regulation. Stimulation of rat pancreatic AR42J cell differentiation towards a neuroendocrine phenotype with activin A or towards an acinar phenotype with dexamethasone, caused strong upregulation of importin alpha3 and alpha4 expression. Phorbol ester-induced differentiation of human leukemia (HL60) cells towards a macrophage phenotype led to downregulation of importin alpha1 and alpha4 expression after 72 hours. Similarly, importins alpha1 and alpha4 displayed a strong downregulation when HL60 cells were directed towards a neutrophil phenotype by DMSO treatment. This study is the first to assess all the human importin alpha isoforms in documenting differential nuclear transport factor regulation during cell proliferation and differentiation.
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PMID:Differential expression of classical nuclear transport factors during cellular proliferation and differentiation. 1243 69

The toxic effects that organic solvents have on whole cells are important drawbacks in the application of these solvents in the production of fine chemicals by whole-cell stereoselective biotransformations. Although early studies found that organic solvents mainly destroyed the integrity of cell membranes by accumulating in the lipid bilayer of plasma membranes, the cellular metabolic responses to the presence of an organic solvent remain unclear. With the rapid development of genomics, it is possible to study cellular metabolism under perturbed conditions at the genome level. In this paper, the global gene expression profiles of Saccharomyces cerevisiae BY4743 grown in media with a high concentration of the organic solvent dimethyl sulfoxide (DMSO) were determined by microarray analysis of ~6,200 yeast open reading frames (ORFs). From cells grown in SD minimal medium containing 1.0% (v/v) DMSO, changes in transcript abundance greater than or equal to 2.5-fold were classified. Genomic analyses showed that 1,338 genes were significantly regulated by the presence of DMSO in yeast. Among them, only 400 genes were previously found to be responsive to general environmental stresses, such as temperature shock, amino acid starvation, nitrogen source depletion, and progression into stationary phase. The DMSO-responsive genes were involved in a variety of cellular functions, including carbohydrate, amino acid and lipid metabolism, cellular stress responses, and energy metabolism. Most of the genes in the lipid biosynthetic pathways were down-regulated by DMSO treatment, whereas genes involved in amino acid biosynthesis were mostly up-regulated. The results demonstrate that the application of microarray technology allows better interpretation of metabolic responses, and the information obtained will be useful for the construction of engineered yeast strains with better tolerance of organic solvents.
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PMID:Microarray analyses of the metabolic responses of Saccharomyces cerevisiae to organic solvent dimethyl sulfoxide. 1254 88

Microbial dimethyl sulfide (DMS) conversion is thought to be involved in the global sulfur cycle. We isolated Pseudomonas putida strain DS1 from soil as a bacterium utilizing DMS as a sole sulfur source, and tried to elucidate the DMS conversion mechanism of strain DS1 at biochemical and genetic level. Strain DS1 oxidized DMS to dimethyl sulfone (DMSO(2)) via dimethyl sulfoxide, whereas the oxidation was repressed in the presence of sulfate, suggesting that a sulfate starvation response is involved in DMS utilization by strain DS1. Two of the five DMS-utilization-defective mutants isolated by transposon 5 (Tn 5) mutagenesis had a Tn 5 insertion in the ssuEADCBF operon, which has been reported to encode a two-component monooxygenase system (SsuED), an ABC-type transporter (SsuABC), and a small protein (SsuF), and also to play a key role in utilization of sulfonates and sulfate esters in another bacterium, P. putida strain S-313. Disruption of ssuD and SsuD enzymatic activity demonstrated that methanesulfonate is a metabolic intermediate of DMS and desulfonated by SsuD. Disruption of ssuC or ssuF also led to a DMS-utilization-defective phenotype. Another two mutants had a defect in a gene homologous to pa2354 from P. aeruginosa PAO1, which encodes a putative transcriptional regulator, while the remaining mutant had a defect in cysM encoding O-acetylserine (thiol)-lyase B.
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PMID:Characterization and identification of genes essential for dimethyl sulfide utilization in Pseudomonas putida strain DS1. 1283 25

One of the major points of debate in determining the effectiveness of nuclear transfer technology has been the phase of the cell cycle of the donor cell at the time of nuclear transfer. Here, a primary mammary cell line has been isolated and various treatments for synchronization of the cell cycle have been tested. The cells were then simultaneously stained for DNA content and protein content and the percentages of cells in G1, G0, S, and G2 + M were estimated. In the first experiment, cells were either cycling, grown to confluence, or serum-starved for 5 days. Serum starvation increased (p < 0.05) the percentage of cells in G0 compared to confluent or cycling cells from 3% to 8% to 22%. By using forward scatter to determine the size of the cells it was determined that if small cells (7-15 microm) were selected from the serum-starved group 43.9% will be in G(0) as compared to 4.5% of cycling cells and 9.9% of confluent cells. Dimethyl sulfoxide (DMSO) treatment (0%, 0.5%, or 1.0%) for 72 hours (shown to synchronize some cell types in G0) had no effect on the percentage of cells in G0, G1, S, or G2 + M. Treatment with mimosine (0 microM, 0.4 microM, 0.8 microM or 1.2 microM), a compound that should synchronize the cells in G1, increased (p < 0.05) the percentage of cells in G1 from 66.7% (0 microM mimosine) to 79.0% to 82.0%. Finally, treatment with colchicine for 24 hours (shown to synchronize some cell types in G2 + M) increased (p < 0.05) the percentage of cells in G2 + M (0 microM colchicine) from 13.3% to 27.2% to 31.6%. It is concluded that many cell cycle synchronization techniques are effective in porcine mammary cell lines, but none of the techniques are 100% effective. Such results should help elucidate the mechanisms involved in nuclear transfer.
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PMID:Cell cycle analysis of cultured porcine mammary cells. 1621 27

The present study was undertaken to examine cell cycle characteristics of endangered Goral (CITES Appendix I) adult skin fibroblasts. Seven experiments were performed, each with a one-way completely randomized design involving three replicates. Least significant difference (LSD) was used to determine variation among treatment groups. Experiment I focused on the effects of cycling, serum-starved, and fully confluent stages of Goral cells. In Experiments II and III, the effects of different antioxidants like beta-mercaptoethanol (beta-ME, 10 microM), cysteine (2 mM), and glutathione (2 mM) were examined after cells were fully confluent without serum starvation for 24 h and 4 h, respectively. In Experiments IV and V, three protease inhibitors, namely 6-dimethylaminopurine (6-DMAP, 2 mM), cycloheximide (7.5 microg/ml) and cytochalasin B (7.5 microg/ml), were used as in Experiment II. In Experiments VI and VII, the effect of different levels of dimethylsulphoxide (DMSO) at 0%, 0.5%, 1.0% and 2.5% were tested by flow cytometry (FACS). In Experiment I, 68.7% of Goral skin fibroblasts reached the G(0)/G(1) stage (2C DNA content) when subjected to the serum-starved medium, which was more than the cycling (64.9%) and fully confluent groups (61.0%) (P > 0.05). Among the chemically treated group, beta-ME, cysteine and DMSO showed better results for synchronization of G(0) + G(1) phases than cycling, serum-starved and fully confluent groups. It can thus be concluded that beta-ME, cysteine and DMSO at certain concentrations can synchronize the cell cycle effectively, which could have a positive impact on somatic cell nuclear transfer in the goral.
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PMID:Cell cycle analysis of in vitro cultured goral (Naemorhedus caudatus) adult skin fibroblasts. 1679 92

The present study was conducted to examine the effect of cell culture conditions, antioxidants, protease inhibitors (PI), and different levels of dimethylsulfoxide (DMSO) for the promotion of synchronization of different cell cycles of Siberian tiger skin fibroblasts. We also compared the ability of somatic cell nuclei of the Siberian tiger in pig cytoplasts and to support early development after reconstruction. Cell cycle synchronization between nuclear donor and recipient cells is considered to be one of the most crucial factors for successful cloning. Five experiments were performed each with a one-way completely randomized design involving three replicates of all treatments. Least significant difference (LSD) was used to determine variation among treatment groups. Experiment I focused in the effects of cycling, serum starved and fully confluent stages of Siberian tiger cells on different cell cycles. In Experiment II, the effects of different antioxidants like beta-Mercaptoethanol (beta-ME, 10 microM), cysteine (2 mM), and glutathione (2 mM) were examined after cells were fully confluent without serum starvation for 4 hr. In Experiment III, three PI, namely 6-dimethylaminopurine (6-DMAP, 2 mM), cycloheximide (7.5 microg/ml) and cytochalasin B (7.5 microg/ml) were used in the sane manner as in Experiment II. In Experiment IV, different levels of DMSO at 0%, 0.5%, 1.0%, and 2.5% were tested on different cell cycle stages of Siberian tiger examined by Flowcytometry (FACS). In Experiment I, 67.2% of the Siberian tiger skin fibroblasts reached the G0/G1 stage (2C DNA content) in fully confluent conditions which was more than the cycling (49.8%) and serum starved (SS) medium (65.5%; P < 0.05). Among the chemically treated group, glutathione (72.6%) and cycloheximide (71.3%) had little bit better results for the synchronization of G0 + G1 phases than serum starved and fully confluent. After nuclear transfer we did not see any significant differences on the development of tiger-porcine reconstructed embryos at cycling, SS and fully confluent. Data indicate that prolonged culture of cells in the absence of serum as well as using different chemicals for this experiment does not imply a shift in the percentage of cells that enter G0/G1 and that confluency is sufficient to induce quiescence. This finding can be beneficial in nuclear transfer programs in Siberian tiger, because there are negative effects, such as apoptosis associated with serum starvation.
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PMID:Cell cycle analysis and interspecies nuclear transfer of in vitro cultured skin fibroblasts of the Siberian tiger (Panthera tigris Altaica). 1707 34

The sigma(54)-dependent transcriptional regulator SfnR is essential for the use of dimethyl sulfone (DMSO(2)) as a sulfur source by Pseudomonas putida DS1. SfnR binds three SfnR-binding sites (sites 1, 2 and 3) within an intergenic region of the divergently transcribed sfnAB and sfnFG gene clusters. The site 1 region, proximal to the sfnF gene, is indispensable for the expression of the sfnFG operon, which encodes components of DMSO(2) monooxygenase. We investigated the transcriptional regulation of the sfnAB operon and possible functions of the sfnA gene. RT-PCR analysis revealed that the sfnAB gene cluster, which is similar to homologues of the acyl-CoA dehydrogenase family, was transcribed as an operon, and its expression was regulated by SfnR under conditions of sulfate starvation. Deletion analyses using lacZ as a reporter demonstrated that the region up to at least -138 bp from the transcription start point of sfnA (containing sites 2 and 3) was necessary for the expression of the sfnAB operon. A growth test of the sfnA-disrupted mutant revealed the possibility that sfnA may be involved in the use of methanethiol as a sulfur source.
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PMID:Transcriptional regulation of the sulfate-starvation-induced gene sfnA by a sigma54-dependent activator of Pseudomonas putida. 1776 52

The aim of this study was to assess by flow cytometry the cell cycle of brown bear fibroblast cells cultured under different growth conditions. Skin biopsies were taken in Cantabria (Spain) from a live, anaesthetized brown bear. DNA analysis was performed by flow cytometry following cell DNA staining with propidium iodide. Serum starvation increased (P<0.01) the percentage of G0/G1 phase cells (92.7+/-0.86) as compared to cycling cells (39.7+/-0.86) or cells cultured to confluency (87.3+/-0.86). DMSO included for 48h in the culture significantly increased (P<0.01) the percentage of G0/G1 phase of the cell cycle at all concentrations used and decreased percentages of S phase in a dose-dependent fashion. Roscovitine increased the G0/G1 phase of the cell cycle (P<0.01) at 15microM concentration. Interestingly, the G2/M stage significantly increased at 30 and 50microM compared to the control and 15microM (P<0.02). The cell cycle of brown bear adult fibroblast cells can be successfully synchronized under a variety of culture conditions.
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PMID:Flow cytometric cell cycle analysis of cultured brown bear fibroblast cells. 1839 24

Cycle synchronization of donor cells in the G0/G1 stage is a crucial step for successful somatic cell nuclear transfer. In the present report, we evaluated the effects of contact inhibition, serum starvation and the reagents - dimethyl sulphoxide (DMSO), roscovitine and cycloheximide (CHX) - on synchronization of canine fibroblasts at the G0/G1 stage. Ear fibroblast cells were collected from a beagle dog, placed into culture and used for analysis at passages three to eight. The population doubling time was 36.5 h. The proportion of G0/G1 cells was significantly increased by contact inhibition (77.1%) as compared with cycling cells (70.1%); however, extending the duration of culture did not induce further synchronization. After 24 h of serum starvation, cells were effectively synchronized at G0/G1 (77.1%). Although synchronization was further increased gradually after 24 h and even showed significant difference after 72 h (82.8%) of starvation, the proportion of dead cells also significantly increased after 24 h. The percentage of cells at the G0/G1 phase was increased (as compared with controls) after 72 h treatment with DMSO (76.1%) and after 48 h treatment with CHX (73.0%) or roscovitine (72.5%). However, the rate of cell death was increased after 24 and 72 h of treatment with DMSO and CHX, respectively. Thus, we recommend the use of roscovitine for cell cycle synchronization of canine ear fibroblasts as a preparatory step for SCNT.
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PMID:Cell cycle synchronization of canine ear fibroblasts for somatic cell nuclear transfer. 1903 1


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