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PubMed1986

[Role of acetate and butyrate in the induction of NADH: rubredoxin oxidoreductase in Clostridium acetobutylicum].

Study of the biosynthesis of NADH: rubredoxin oxidoreductase in resting cells of Clostridium acetobutylicum shows that this enzyme is synthesized at a maximal rate in the presence of acetic acid at a concentration of 3 g . l-1 and at pH 4.8. Protons do not play any role in this biosynthesis since no induction is observed in a medium without acetate for the same values of pH. Butyric acid at a concentration of 0.5 g . l-1 gives 50% induction and formic acid, isobutyric acid and propionic acid have no inductive action on NADH: rubredoxin oxidoreductase. These results are confirmed by studies using a dialysis bag. Only a culture against acetic acid at an initial concentration of 2 g . l-1 gives maximal biosynthesis of the enzyme, whereas a culture in which all products of metabolism are eliminated gives an activity which is 80% lower.

Acetates↗

PubMed1987

Inhibitory effect of retinoid (E5166) on cell growth and suppressive effect on Epstein-Barr virus early-antigen induction by n-butyrate in nasopharyngeal hybrid cells.

The in vitro proliferation and colony-forming activity (plating efficiency) of Epstein-Barr virus (EBV) nuclear antigen-positive nasopharyngeal hybrid cells were inhibited by one of the retinoid, polyprenoic acid; E5166. It was dependent on retinoid concentration. Furthermore, an induction of EBV early antigen after treatment with 4 mM n-butyrate was markedly suppressed by E5166 and this was similar to the previously reported effects of retinoid acid on iododeoxyuridine (IUDR) and 12-O-tetra-decanoyl-phorbol-13-acetate (TPA) induction. These results support to lead a clinical application of E5166 for combination chemotherapy in patients with nasopharyngeal carcinoma.

Antigens, Viral, Tumor↗

PubMed1996

Genes related to growth and invasiveness are repressed by sodium butyrate in ovarian carcinoma cells.

Down-regulation of oncogene expression is one of the hallmarks of the process whereby transformed cells are forced into differentiation and/or growth arrest by potent inducers and therefore can represent an interim end point in cancer treatment. The differentiation inducer sodium butyrate (NaB) arrested growth of N.1 ovarian carcinoma cells and repressed expression of cyclin D1/prad1 and the invasiveness-related protease plasminogen activator-urokinase (plau). This was accompanied by the acquisition of a differentiated morphology, all of which characteristics were maintained as long as N.1 cells were exposed to the inducer. In accordance with a differentiated phenotype was the finding that fibronectin expression was increased significantly. Recently, it was shown that NaB represses the transcription factor c-myc by blocking Ca2+ signals and modulating serine threonine kinase activity. We wanted to investigate NaB-mediated interference on signals contributing to the expression on prad1, plau and growth arrest-specific 6 (gas6). Protein kinase A (PKA) inactivation de-repressed prad1 and plau transcript levels. NaB had onlygeneral but no specific influence on PKA-modulated prad1 and plau expression however. Protein kinase C activation up-regulated plau transcript levels, but not that of prad1. Prad1 expression seemed to depend on Ca2+-triggered signals. Constitutive plau expression was insensitive to additional Ca2+-mediated signals, but it became responsive upon NaB treatment.

Adenylyl Cyclases↗

PubMed1997

Time-course of butyric acid-induced differentiation in human K562 leukemic cell line: rapid increase in gamma-globin, porphobilinogen deaminase and NF-E2 mRNA levels.

Butyric acid (BA) was shown to induce hemoglobinization of K562 cells in a dose- and time-dependent manner. The maximal differentiation (54% of hemoglobinized cells) was obtained with the 0.5 mM concentration, which induced a 60% inhibition of cell growth at day 3 without cytotoxicity. Parallel to the kinetics of hemoglobinization, a rapid increase in gamma-globin and porphobilinogen deaminase (PBGD) mRNAs was observed in BA-treated cells. This increase was time-dependent and higher for gamma-globin than for PBGD (six- and two-fold at day 3, respectively). In contrast, erythropoietin receptor mRNAs were not affected by BA treatment. Analysis of erythroid transcription factor mRNA levels during the time course of BA treatment showed, for the first time, an early and marked (up to three-fold) increase in p45 NF-E2 mRNA, contrasting with that of GATA-1 mRNA (<1.5-fold). Taken together, these results showed the rapid differentiating effect of BA and suggest the involvement of the NF-E2 transcription factor.

Butyrates↗

PubMed1988

Inorganic pyrophosphate is located primarily in the mitochondria of the hepatocyte and increases in parallel with the decrease in light-scattering induced by gluconeogenic hormones, butyrate and ionophore A23187.

1. The effects of a variety of hormones on the PPi content and light-scattering of isolated rat liver cells was studied. 2. The basal PPi content was about 130 pmol/mg of cell protein, and increased after hormone addition, in parallel with a decrease in light-scattering which we have observed previously [Quinlan, Thomas, Armston & Halestrap (1983) Biochem. J. 214, 395-404]. 3. The mean increases in PPi content with the agonists shown (as pmol/mg of protein) were: 0.1 microM-glucagon, 25; 20 microM-phenylephrine, 30; 25 nM-vasopressin, 127; glucagon + phenylephrine, 115; glucagon + vasopressin, 382; 100 microM-ADP, 50; 15 microM-A23187, 72; 1 mM-butyrate, 80. 4. In the absence of extracellular Ca2+, vasopressin had little effect on either the PPi content or the light-scattering of hepatocytes. 5. The magnitude of the increase in PPi content correlated with that of the decrease in light-scattering irrespective of the stimulating agent, provided that the PPi did not exceed 300 pmol/mg of protein. Above this value little additional change in light-scattering was observed. 6. Subcellular fractionation showed that over 90% of the cellular PPi was intramitochondrial in both control and stimulated cells. 7. The data support the conclusions of previous experiments using isolated liver mitochondria [Davidson & Halestrap (1987) Biochem. J. 246, 715-723] that hormones increase the mitochondrial matrix volume through a Ca2+-induced rise in matrix [PPi]. 8. It is further proposed that this increase in mitochondrial [PPi] allows entry of ADP into the mitochondria in exchange for PPi and is therefore responsible for the increase in total mitochondrial adenine nucleotides observed after hormone treatment.

Animals↗

PubMed1989

Biochemical localization of the transformation-sensitive 52 kDa (p52) protein to the substratum contact regions of cultured rat fibroblasts. Butyrate induction, characterization, and quantification of p52 in v-ras transformed cells.

A 52 kDa protein (p52) was identified, using differential extraction and electrophoretic criteria, as a major extracellular and substrate-associated component of normal rat kidney (NRK) fibroblasts. Cells transformed with Kirsten murine sarcoma virus (KNRK cells) did not express p52 constitutively, but were inducible for both p52 production and its substrate association during culture in sodium butyrate (NaB)-supplemented growth medium. Comparative analysis of the relative molecular mass, subcellular distribution, and isoelectric complexity (five variants ranging in pI from 5.4 to 6.2) of the 52 kDa species constitutively and inducibly expressed by NRK and KNRK/NaB cells respectively, indicated that they were, indeed, the same protein. p52 selectively localized to cellular fractions enriched in substrate focal contact sites and associated ventral undersurface components. NaB induction of p52 in KNRK cells occurred before cell spreading; other polar compounds, such as dimethyl sulphoxide, which did not induce KNRK cell spreading, similarly failed to elicit p52 production. p52 accumulated more rapidly in (and was quickly released from) the focal-contact-enriched protein fraction of NRK cells compared with its time course of appearance in the medium. These data collectively suggest that p52 is one of a relatively small number of proteins the synthesis of which is either involved in determination of cell shape or regulated as a consequence of cell-shape changes.

Animals↗

PubMed1991

p52(PAI-1) and actin expression in butyrate-induced flat revertants of v-ras-transformed rat kidney cells.

Flat revertants of v-ras-transformed (KNRK) rat kidney cells, which express elevated levels of p21ras protein, were generated to high efficiencies with sodium butyrate (NaB). Overall protein synthesis in revertants was not different from parental cells, although changes were evident in expression and distribution of specific microfilament-associated cytoskeletal proteins. Quantitative two-dimensional electrophoresis revealed revertant-associated 3-4-fold increases in cytoskeletal deposition of the microfilament-associated proteins gelsolin and vinculin correlating with microfilament reorganization and focal-contact formation respectively. Similar increases in actin content were evident at both the total-cellular- and cytoskeletal-associated-protein levels. In contrast, intermediate-filament family elements (vimentin, lamins) remained unaltered. The only unique protein resolved in flat revertants was p52, a 52 kDa extracellular-matrix-associated protein previously identified as plasminogen-activator inhibitor type 1 (PAI-1). p52(PAI-1) expression was induced early during generation of the revertant phenotype and preceded development of focal-contact structures. NaB-induced p52(PAI-1) synthesis and generation of early morphological reversion in KNRK cells required ongoing RNA synthesis, since exposure to actinomycin D before addition of NaB inhibited both events. p52(PAI-1) induction by NaB was regulated at the level of mRNA abundance; in contrast, actin mRNA levels were the same in parental and revertant cells, suggesting that the increased actin content which typified the revertant phenotype was due to augmented actin microfilament stability.

Animals↗

PubMed1992

Butyric acid-induced differentiation of HL-60 cells increases the expression of a single lysophospholipase.

Treatment of HL-60 cells with 0.5 mM-butyric acid resulted in morphological changes, including the formation of cytoplasmic granules, nuclear condensation and segmentation. These differentiated cells had an elevated phospholipase A2 activity and an increased capacity to synthesize a variety of eicosanoids, including both lipoxygenase and cyclooxygenase products. Phospholipase A2-mediated release of arachidonic acid is accompanied by an equimolar production of potentially cytotoxic lysophospholipid. In association with the differentiation process, there was a 2-3-fold increase in lysophospholipase activity. Subsequent studies were undertaken to identify and characterize the lysophospholipases in this cell system, with 1-[1-14C]palmitoyl-2-hydroxy-sn-glycero-3-phosphocholine as substrate. Hydrophobic chromatography of both undifferentiated and differentiated cell extracts revealed three peaks of enzyme activity. Extracts of differentiated cells contained a dramatic increase in activity contained in peak 2. The increase in enzymic activity of peak 2 appeared to account for the increase in total lysophospholipase activity found in the differentiated cell homogenates. The lysophospholipases contained in peaks 2 and 3 were purified to homogeneity and were 20 and 22 kDa respectively, as determined by denaturing polyacrylamide-gel electrophoresis. Peaks 2 and 3 were similar on the basis of amino acid composition, but had distinctive C-terminal peptide amino acid sequences. Enzymic characterization of these proteins demonstrated that there was no detectable level of non-specific esterase, acyltransferase or transacylase activity associated with these proteins. We concluded that peak 2 lysophospholipase is regulated by differentiation in HL-60 cells and may play an important role in protecting these cells from the cytolytic effects of the lysophospholipids produced by the activation of phospholipase A2.

Amino Acid Sequence↗

PubMed1995

Expression of human platelet-activating factor receptor gene in EoL-1 cells following butyrate-induced differentiation.

Platelet-activating factor (PAF) is a potent lipid mediator of allergic inflammation through its interaction with eosinophils. Expression of the PAF receptor is modulated by many agents, including those responsible for cell differentiation. We report here that differentiation of a human eosinophilic leukaemia cell line, EoL-1, by sodium n-butyrate is associated with induction of PAF receptor gene expression, as indicated by: PAF receptor mRNA accumulation; increases in the binding of [3H]WEB 2086, a PAF antagonist; analysis of cell-surface expression of PAF receptor protein using a monoclonal anti-(PAF receptor) antibody; and augmentation of PAF-induced increase in the intracellular concentration of calcium. Using cDNA cloning, the receptor expressed in EoL-1 cells was identified as 'Transcript 1', one of two transcripts which was previously reported from human genomic analysis (Mutoh, Bito, Minami, Nakamura, Honda, Izumi, Nakata, Kurachi, Terano and Shimizu (1993) FEBS Lett. 322, 129-134). The PAF-induced calcium response and phosphoinositide turnover were decreased by pertussis toxin (PTX) treatment, suggesting that these signals are coupled largely with PTX-sensitive G-protein(s) in EoL-1 cells. These systems may provide a useful experimental model with which to investigate the relationship between eosinophilic differentiation and PAF receptor induction, and the role of eosinophils in allergic responses.

Amino Acid Sequence↗

PubMed1985

5-Azacytidine and sodium butyrate induce expression of aromatase in fibroblasts from chickens carrying the henny feathering trait but not from wild-type chickens.

Male chickens with the henny feathering trait have a female feathering pattern. In two henny-feathered breeds, the Sebright bantam and the Golden Campine, the synthesis of estrogen is increased as a consequence of increased activity of aromatase, a cytochrome P-450 enzyme that converts androgen to estrogen. The activity of the enzyme is elevated in tissue slices and in cultured fibroblasts from heterozygous and homozygous birds of both breeds. In contrast, aromatase activity is very low in extraglandular tissues from control chickens and is undetectable in fibroblasts cultured from these tissues. The current studies show that two agents known to alter gene expression--5-azacytidine and sodium butyrate--markedly induce expression of aromatase activity in Sebright and Campine fibroblasts but have no effect on aromatase activity in fibroblasts from wild-type chickens. Induction of aromatase is specific since two other microsomal enzymes in chicken fibroblasts--one, a component of the aromatase enzyme complex and the other a cytochrome P-450 oxidase distinct from the aromatase--are not significantly affected by these agents. Further study of this unique mutation should provide insight into the mechanisms by which genes are switched to an uninducible state during differentiation.

Animals↗

PubMed1995

Use of sodium butyrate to enhance production of retroviral vectors expressing CFTR cDNA.

Previously, we constructed a retrovirus vector (LCFSN) for transduction and expression of the cDNA encoding the normal human cystic fibrosis transmembrane conductance regulator (CFTR). The titer of virus from amphotropic packaging cells producing the LCFSN vector was low (10(3)-10(4) infectious units/ml). In an attempt to increase virus production, we used sodium butyrate (NaB) to treat murine retrovirus packaging cells producing this vector. NaB treatment increased the production of LCFSN from between 20-fold to greater than 1,000-fold, depending upon the producer clone, thereby resulting in virus titers up to about 1 x 10(7) infectious units/ml. This induction of virus titer could be accounted for, at least in part, by an increase in steady-state levels of full-length vector RNA within the producer cells. With some clonal producer cell lines, lowering the temperature of the virus harvest in combination with NaB treatment resulted in an apparent synergistic increase in virus production. The production of retrovirus vectors containing genes other than CFTR could also be increased by NaB treatment, although the enhancement in titer was modest (2-fold to 10-fold). The increase in virus production was not accompanied by an induction of replication-competent helper virus. NaB treatment also increased the transient production of retroviral vectors following DNA-mediated transfection into packaging cells such that virus titers of greater than 10(6) infectious units/ml could be readily attained.

Butyrates↗

PubMed1986

Butyrate induced accumulation of a 2.3 kb polyadenylated H1(0) histone mRNA in HeLa cells.

Sodium butyrate was used to induce the accumulation of human H1(0) mRNA in HeLa cells. The length of this mRNA (2,300 nucleotides) was determined by Northern blot hybridization and S1 nuclease analysis using a human H1(0) gene probe. The mRNA shows long 5' and 3' non coding segments and it is polyadenylated. The signal for this step of mRNA maturation (cleavage and polyadenylation) appears to be the hexanucleotide AAUAAA in analogy to most (other than histone) mRNA species. Thus, the mode of maturation of H1(0) mRNA differs, on one hand, from that of the cell cycle dependent mRNA species, where it is based on a specific stem-and-loop structure. On the other hand, the 3' end of H1(0) mRNA varies from H5 mRNA, which is characterized by two unique dyad symmetry structures at its 3' end.

Base Sequence↗

PubMed1989

Enhanced transfection efficiency and improved cell survival after electroporation of G2/M-synchronized cells and treatment with sodium butyrate.

To achieve high transfection efficiency in human fibroblasts with good preservation of proliferative capacity we developed an electroporation procedure that combines two distinct modalities: use of recipient cells synchronized in the late G2/mitotic phase of the cell cycle and treatment of cells post-electroporation with 5 mM butyrate. This combination enabled reduction of plasmid DNA concentration and electroporation voltage, both associated with cytotoxicity, while greatly enhancing transfection efficiencies. Although the method was primarily developed for transient expression it was also found to improve stable expression. This procedure should have wide applicability, particularly in studies seeking to identify DNA sequences that lead to inhibition of DNA synthesis and proliferation in human fibroblasts and other cells refractory to transfection.

Butyrates↗

PubMed1993

Induction of phenotypic changes in SCLC cell lines in vitro by hexamethylene bisacetamide, sodium butyrate, and cyclic AMP.

BACKGROUND: Hexamethylene bisacetamide (HMBA), sodium butyrate (NaBt), and cyclic AMP (cAMP) have been shown to induce differentiation, which may regulate tumour growth differently from conventional cytotoxic drugs. It was the intention in the present study to determine whether alterations could be induced in the phenotype of small cell lung cancer (SCLC) cell lines with HMBA, NaBt and cAMP, and whether these alterations would correlate with reduced growth in vivo, implying a phenotypic shift from malignancy towards differentiation. MATERIALS AND METHODS: The cell lines were NCI-H69, H187 and H128. The activity of dopa decarboxylase (DDC), the BB isozyme of creatine kinase (CK-BB), the synthesis of bombesin-like peptide (BLI), and the presence of neurone specific enolase (NSE) and chromogranin were used as markers of the small cell phenotype. Clonogenicity in suspension in agar, and growth as xenografts in nude mice, were used as malignancy-associated properties. Cell proliferation in vitro was determined by cell counting and growth curve analysis. RESULTS: HMBA, NaBt and cAMP were found to be reversibly cytostatic in liquid culture and pre-exposure reduced the cloning efficiency in agar by 60%-80%. Growth as xenografts was inhibited (three- to five-fold increase in the tumour doubling time), most significantly by NaBt. Effects of phenotypic markers were more complex. The most significant were a two-fold reduction in DDC with NaBt and HMBA, a 50% increase in CK-BB with cAMP, and a 70%-100% increase in secreted BLI with HMBA and cAMP, in NCI-H69 cells. No significant effects were seen on NSE and chromogranin. There was little sign of an interaction with adriamycin and vincristine, although a slight increase was observed in the ID50 of VP-16 following treatment with cAMP. CONCLUSIONS: NaBt, HMBA and cAMP were cytostatic and inhibited tumour growth, but there was no coordinated response in marker expression that would confirm phenotypic alteration indicative of differentiation. The problem of defining differentiation in SCLC further complicated the analysis. The possibility remains of combining these agents with conventional cytotoxics as there appears to be little antagonistic effect, and other studies have suggested synergism may be possible with correct scheduling.

Acetamides↗

PubMed1996

Histone hyperacetylation plays a role in augmentation of IL-4-induced IgE production in LPS-stimulated murine B-lymphocytes by sodium butyrate.

We previously reported the augmentation by sodium butyrate (NaBu) of IL-4-induced IgE production in LPS-stimulated murine B-lymphocytes. Histone deacetylase inhibition may be involved in the molecular mode of action of NaBu. Thus, this study was accomplished to examine the involvement of histone hyperacetylation in IL-4-induced class switching promotion by NaBu with a specific histone deacetylase inhibitor, trichostatin A (TSA). TSA was found to enhance IL-4-dependent IgE production in a concentration-dependent manner (0.3-30 nM) as did NaBu, although neither compound affected the IgE production in the absence of IL-4. The effect of combined addition of suboptimal concentrations of NaBu and TSA to the culture appeared to be additive, not synergistic. Moreover, the intense of enhancement of IgE production observed by addition of both compounds at optimal concentrations appeared to be equivalent to that obtained with each maximal concentration. Furthermore, enhancement of IgE production by TSA or NaBu was confirmed to be absolutely IL-4 dependent and was not due to the shift of kinetics. On the other hand, various cell cycle inhibitors such as caffeine and theophylline (G1 or G2-arrest), hydroxyurea (S-arrest), and colchicine (M-arrest), none of which have the ability to inhibit histone deacetylase, were shown to have no effect. These findings suggest that histone hyperacetylation plays an important regulatory role in the modification of IL-4-dependent class switching to C epsilon in LPS-stimulated murine B-cells by NaBu.

Animals↗

PubMed1992

Beta-oxidation of butyrate, the short-chain-length fatty acid, occurs in peroxisomes in the yeast Candida tropicalis.

When an n-alkane-utilizable yeast, Candida tropicalis pK233, was cultivated on butyrate, the fatty acid of shortest chain-length for beta-oxidation, as the sole source of carbon and energy, catalase and the enzymes of the fatty acid beta-oxidation system were inducibly synthesized at high levels. As in the alkane-grown cells, the proliferation of peroxisomes was harmonized with the induction of peroxisomal enzymes. The results of subcellular fractionation and immunoelectronmicroscopy indicated the localization of these enzymes in peroxisomes, not in mitochondria. It was suggested that only peroxisomes have a role in fatty acid beta-oxidation in the yeast cells, unlike in mammalian cells, in which cooperation between peroxisomes and mitochondria is essential.

Acetyl-CoA C-Acyltransferase↗

PubMed1993

Isolation of a mitomycin-resistant human lung adenocarcinoma cell subline to investigate the modulation by sodium butyrate of cell growth and drug resistance.

We developed a mitomycin C (MMC)-resistant human lung adenocarcinoma cell subline, SPC-A1/DM4, from cloned SPC-A1/D13 parent cells by 1 h exposures to escalating concentrations of the drug over 17 months. A 5.9-fold resistance to MMC and a 3.8-fold cross-resistance to cisplatin were present in resistant cells compared with parent cells. This phenotype was stable in the absence of drug exposure for at least 6 months. Sodium butyrate (NaBu), a widely used differentiating agent, was shown to inhibit cell proliferation in a dose-dependent manner, with the cytostatic concentration of 2 mM. This NaBu-induced growth inhibition was reversible. However, SPC-A1/DM4 cells, after recovery from the cytostasis induced by 2 days treatment with 2 mM NaBu, became 2-fold more sensitive to MMC than the cells not exposed to the agent. Meanwhile, the cisplatin response of these treated cells reached a level comparable to the parent cells. This modulation by NaBu of drug resistance could be retained for at least 1 month. Treatment with 2 mM NaBu for 2 days caused inhibition of DNA synthesis and accumulation of cells in the G1 and G2/M-phases of the cell cycle. Correlated with these were a marked increase of protein content in these cell subpopulations and an enhanced RNA synthesis. In addition, NaBu-treated cells acquired development of endoplasmic reticulum and accumulated lipid droplets. These morphological alterations were accompanied by a significant decrease in the ratio of nuclear to cytoplasmic areas. These findings suggest that NaBu is potentially useful in the treatment of drug-resistant non-small cell lung cancer. Information about the NaBu-induced phenotypic alterations may offer a clue to the understanding of its long-term effect on drug resistance.

Adenocarcinoma↗

PubMed1994

Antiproliferative effects of sodium butyrate in adriamycin-sensitive and -resistant human cancer cell lines.

The proliferation of the MCF7 and MCF7-A (adriamycin-resistant) and KB-3-1 and KB-A (adriamycin-resistant) cell lines was arrested by sodium butyrate (NaBut) at 1 mM or higher concentrations. In the MCF7 and MCF7-A cell lines, an accumulation in the G1 phase was observed, whereas the KB-3-1 and KB-A cell lines accumulated in both G1 and G2/M phases. The level of the mRNA coded by the 'early G1' gene c-myc was high in all these cell lines, and was only transiently decreased by NaBut treatment. The 'late' mRNA coding for the proliferating cell nuclear antigen (PCNA) was also strongly expressed in all the cell lines studied; incubation with NaBut caused a decrease of the PCNA mRNA in the MCF7 and MCF7-A cells but not in the KB-3-1 and KB-A cells. The anti-oncoprotein p105RB was undetectable in the MCF7 and MCF7-A cells, while the KB-3-1 as well as KB-A cells contained a high level of this protein. Neither the content nor the apparent state of phosphorylation of the RB protein were affected by incubation (up to 48 h) with NaBut.

Butyrates↗