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PubMed1994

Positive modulation of the adipoconversion of adipoblasts derived from genetically obese rats by sodium butyrate.

Using a new serum-free primary culture system, we have previously reported genotypic differences between adipoblasts derived from the epididymal adipose deposit of lean and obese 8-week-old Zucker and Wistar Diabetic Fatty (WDF) rats (15). In these strictly controlled culture conditions, obese-derived adipoblasts expressed low levels of the late markers of differentiation (lipid accumulation, GPDH). In order to further characterize obese-derived adipoblasts and analyze the critical relationship between growth and differentiation, growth arrest was induced in lean- and obese-derived cultures using sodium butyrate treatment. Addition of 2.5 mM sodium butyrate to the serum-free medium from day 1 reduced markedly the growth of lean as well as obese-derived cells. Adipoconversion of lean-derived adipoblasts was not altered, similar levels of LPL and GPDH activities being obtained in control and butyrate-treated groups. By contrast, a marked increase in both activities was observed in obese-derived cultures, restoring the level of both markers of differentiation to the lean level. Similar results were obtained with adipoblasts derived from subcutaneous inguinal (ING) fat pad of obese Zucker as well as adipoblasts derived from ING and EPI fat deposits from obese WDF rats. Taken together, these results suggest that adipose deposits of these genetically obese rats contain a specific adipoblast population which differs from lean-derived adipoblasts in respect to its adipoconversion capacity and/or its stage of commitment to differentiation.

Adipocytes↗
PubMed1980

Sodium butyrate affects expression of fibronectin on CHO cells: specific increase in antibody-complement-mediated cytotoxicity.

Cellular fibronectin is expressed only at very low levels on the surface of the spontaneously transformed Chinese Hamster Ovary (CHO) cell line, as detected by immunofluorescence studies and confirmed by resistance of CHO cells to complement-mediated lysis in the presence of anti-fibronectin antibody. Treatment of CHO cells with sodium butyrate results in a marked susceptibility to anti-fibronectin complement-mediated killing. Using selected complement-containing sera from rabbits, it is possible to demonstrate that killing of butyrate-treated CHO cells is absolutely and specifically dependent on the presence of antibody to fibronectin. The increased susceptibility of butyrate-treated cells to complement-mediated killing correlates with an increase in cell surface fibronectin detected by immunofluorescence studies. This increased antigen expression should allow the isolation of mutants with altered regulation of fibronectin expression in a cell line of proven value for somatic cell genetic studies.

Animals↗
PubMed1993

Analogues of butyric acid that increase the expression of transfected DNAs.

Butyric acid has many strong effects on gene expression in mammalian and viral systems, as well as in increasing the expression of recombinant DNAs artificially introduced into cultured cells. We screened 14 analogues of butyric acid for their ability to upregulate expression from 3 different recombinant chloramphenicol acetyltransferase expression vectors stably integrated into NIH 3T3 cells that had been transformed by calcium phosphate transfection or electroporation. Butyric acid, 2-bromobutyric acid, 3-bromopropionic acid, 3-mercaptopropionic acid, vinylacetic acid, and butyraldehyde were found to upregulate human immunodeficiency viral long terminal repeat-, SV40 early gene promoter-, and glucocerebrosidase promoter-directed expression of heterologous genes in cultured cells. Three other analogues had lesser effects; and 6 additional analogues had very little, if any, effect.

3T3 Cells↗
PubMed1999

Redistribution of activated caspase-3 to the nucleus during butyric acid-induced apoptosis.

The colonic epithelial cells near the top of the crypt and in the lumen have been shown to undergo apoptosis. Since butyric acid is the major short-chain fatty acid produced by fermentation of dietary fiber in the large bowel, it has been proposed that it could act as an important regulator of apoptosis in colorectal cancer. Here we report that in cells treated with butyric acid, the cleavage of DNA-PKcs was paralleled or preceded by the induction of activation of caspase-3, and these events were inhibited by Bcl-2 overexpression. We also demonstrated the redistribution of activated caspase-3 to the nuclear compartment where it locally cleaves DNA-PKcs and poly(ADP-ribose) polymerase, and cleaved fragments were released in the cytosolic compartment. The observed activation of caspase-3 and nuclear cleavage of its substrates and their subsequent release into the cytosol were inhibited by a specific caspase-3 inhibitor, the tetrapeptide DEVD-CHO. These findings suggest that relocalization of activated caspase-3 to the nucleus may constitute an important apoptotic signal during butyric acid-induction of apoptosis human colorectal cancer cells.

Apoptosis↗
PubMed1998

Arginine butyrate-induced susceptibility to ganciclovir in an Epstein-Barr-virus-associated lymphoma.

Lymphoproliferative disorders associated with Epstein-Barr virus (EBV) infections can occur in the setting of immunosuppression. In some patients, the lymphoproliferative disorder can resemble an aggressive monoclonal non-Hodgkins lymphoma (NHL). These NHL are poorly responsive to conventional therapy. Similarly, antiviral therapy with synthetic nucleosides such as ganciclovir are ineffective because the genes that render the virus susceptible to therapy are not expressed in EBV+ lymphomas. Using a cell line derived from a lung transplant recipient with an EBV+ immunoblastic NHL, we studied the ability of arginine butyrate to induce the expression of EBV thymidine kinase. Arginine butyrate was not only effective in inducing EBV thymidine kinase transcription, but also acted synergistically with the antiviral agent ganciclovir to inhibit cell proliferation and decrease cell viability. Based on these findings, the patient from whom the cell line was derived was treated with arginine butyrate/ganciclovir as well as conventional cytotoxic chemotherapy. No additional toxicity was observed with the arginine butyrate/ganciclovir therapy. Histologic examination of the tumor showed substantial necrosis. These observations suggest the feasibility of arginine butyrate induction of ganciclovir susceptibility in patients with EBV-associated lymphomas.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Deoxycholate inhibits in vivo butyrate-mediated BrDU labeling of the colonic crypt.

The short-chain fatty acid butyrate (NaBu) selectively increases colonic crypt base proliferation and inhibits "premalignant" crypt surface hyperproliferation while the secondary bile acid deoxycholate (DCA) induces surface hyperproliferation, in vitro. We hypothesized that NaBu and DCA have similar selective and antagonistic effects on the colonic crypt proliferative pattern, in vivo. Fifty-six adult SD rats underwent surgical isolation of the colon and 24-hr intraluminal instillation with physiological (10 mM) and pharmacological (25 mM) levels of butyrate alone or combined with a physiological DCA level (5 microM). Bromodeoxyuridine-labeling indices (LI) were determined as labeled cells divided by total cells, for the whole crypt and five crypt compartments from base to surface. Treatment with NaBu increased total LI when compared to NaCl. This effect was significant only at the crypt base. Both doses of NaBu resulted in similar LI with no further response at the higher concentration. In contrast to prior in vitro studies, DCA alone at this concentration did not affect LI, but when combined with NaBu, DCA inhibited the effects of NaBu at the crypt base and surface. The conclusions are: (1) the in vivo proliferative effects of NaBu are selective to the crypt base, (2) an in vivo low physiological DCA level does not promote crypt surface hyperproliferation but does inhibit butyrate's proliferative effect, and (3) NaBu and DCA interact in a complex and antagonistic manner to selectively modulate crypt base and surface proliferation, in the rat colon, in vivo. These findings may have clinical relevance since colonic levels of NaBu and DCA are affected by diet.

Animals↗
PubMed1982

Effects of sodium butyrate, a new pharmacological agent, on cells in culture.

Sodium butyrate, at millimolar concentrations, when added to cell cultures produces many morphological and biochemical modifications in a reversible manner. Some of them occur in all cell lines. They concern regulatory mechanisms of gene expression and cell growth: an hyperacetylation of histone resulting from an inhibition of histone deacetylase and an arrest of cell proliferation are almost constantly observed. Some other modifications vary from one cell type to another: induction of proteins, including enzymes, hormones, hemoglobin, inhibition of cell differentiation, reversion of transformed characteristics of cells to normal morphological and biochemical pattern, increase in interferon antiviral efficiency and induction of integrated viruses. Most if not all these effects of butyrate could result from histone hyperacetylation, from changes in chromatin structures as measured by accessibility to DNases and from modifications in cytoskeleton assembly. We do not know at the present time whether butyrate acts on a very specific target site in cell or if it acts on several cell components.

Acetylation↗
PubMed1981

Multiple effects of 5 mM sodium butyrate on Physarum polycephalum macroplasmodia.

In a Physarum polycephalum macroplasmodium, nuclei naturally divide synchronously. Thus, it offers an opportunity to study growth and mitosis within a true organism. The effects of 5 mM sodium-butyrate on these processes have been examined. When this material is added to the culture medium during mitosis, the butyrate acts like a fixative on condensed chromosomes. During interphase, this short fatty acid stops growth and immediately inhibits DNA synthesis. Furthermore, it prevents differentiation in macroplasmodia induced to spherulate. All these modifications are readily reversible after transfer to a medium lacking butyrate.

Butyrates↗
PubMed1982

Butyrate: a cytotoxin for Vero cells produced by Bacteroides gingivalis and Bacteroides asaccharolyticus.

Culture filtrates of B. gingivalis and B. asaccharolyticus are cytotoxic for Vero cells. It is shown that the cytotoxic effect is due to the butyrate concentrations present in the culture filtrates of these strains. This cytotoxic effect proved to be reversible. Strains of the B. melaninogenicus subspecies intermedius and melaninogenicus did not produce butyrate and did not show cytotoxic activity towards Vero Cells. The significance of the production of toxic concentrations of butyrate for the etiology of especially periodontal diseases is discussed.

Animals↗
PubMed1995

Role of formate and hydrogen in the degradation of propionate and butyrate by defined suspended cocultures of acetogenic and methanogenic bacteria.

The butyrate-degrading Syntrophospora bryantii degrades butyrate and a propionate-degrading strain (MPOB) degrades propionate in coculture with the hydrogen- and formate-utilizing Methanospirillum hungatii or Methanobacterium formicicum. However, the substrates are not degraded in constructed cocultures with two Methanobrevibacter arboriphilus strains which are only able to consume hydrogen. Pure cultures of the acetogenic bacteria form both hydrogen and formate during butyrate oxidation with pentenoate as electron acceptor and during propionate oxidation with fumarate as electron acceptor. Using the highest hydrogen and formate levels which can be reached by the acetogens and the lowest hydrogen and formate levels which can be maintained by the methanogens it appeared that the calculated formate diffusion rates are about 100 times higher than the calculated hydrogen diffusion rates.

Butyrates↗
PubMed1979

Induction of alkaline phosphatase activity in HeLa cells by sodium butyrate.

The induction of HeLa cell alkaline phosphatase activity by sodium butyrate could be inhibited by the coadministration of caffeine or theophylline. The inhibitions were dose dependent, and at any given concentration the potency was theophylline greater than caffeine. Although the induction by sodium butyrate was more sensitive to the inhibition by the xanthines than was that produced by 5-iodo-2'-deoxyuridine, the magnitudes of the increases in cyclic AMP concentrations after treatment with the xanthines were similar in the inhibition of both types of induction. The induction of alkaline phosphatase activity by sodium butyrate also produced a shift in the thermostability pattern of the enzyme, with a proportionately greater increase in the heat-labile, rather than heat-stable, form of the activity.

Alkaline Phosphatase↗
PubMed1981

Effect of sodium butyrate on the hepatoma cell cycle: possible use for cell synchronization.

Exposure of HTC cells to sodium butyrate caused inhibition of growth. The site of growth inhibition was studied by time-lapse cinematography and [3H]thymidine incorporation studies. Evidence is presented that sodium butyrate affected the cell cycle at a specific point immediately after mitosis. Inasmuch as it does not modify the interphase duration after its removal, butyrate may be used for HTC synchronization.

Animals↗
PubMed2003

Characterization and transcription of the genes encoding enzymes involved in butyrate production in Butyrivibrio fibrisolvens.

Genes encoding enzymes that catalyze butyryl-CoA formation from acetyl-CoA in a type II strain of Butyrivibrio fibrisolvens were analyzed. The genes encoding thiolase, beta-hydroxybutyryl-CoA dehydrogenase, butyryl-CoA dehydrogenase, and electron transfer flavoproteins were clustered, but the crotonase gene was not present in this region. The deduced amino acid sequences of these enzymes were similar to those of clostridia. The clustered genes were shown to be cotranscribed. The rate of butyrate production increased with an increase in acetate concentration in the medium up to 5 mM, suggesting that the butyryl-CoA/acetate CoA transferase reaction limits butyrate production. Transcription of the clustered genes was not affected by acetate concentration, suggesting that acetate does not affect the synthesis of enzymes involved in butyryl-CoA formation. These results confirm that acetate stimulates butyrate production by acting as a CoA acceptor in the butyryl-CoA/acetate CoA transferase reaction.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed2006

Inhibition of telomerase enhances apoptosis induced by sodium butyrate via mitochondrial pathway.

Telomerase activation represents an early step in carcinogenesis. Increased telomerase activity in cervical cancer suggests a potential target for the development of novel therapeutic drugs. The aim of this study is to investigate the impact of telomerase activity on the biological features of HeLa cells and the possible mechanisms of enhanced apoptosis rate induced by sodium butyrate after telomerase inhibition. We introduced vectors encoding dominate negative (DN)-hTERT, wild-type (WT)-hTERT, or a control vector expressing only a drug-resistance marker into HeLa cells. Thus we assessed the biological effects of telomerase activity on telomere length, cell proliferation, chemosensitivity and radiosensitivity. In order to understand the mechanisms in which DN-hTERT enhances the apoptosis induced by sodium butyrate, we detected the release status of cytochrome c and apoptosis inducing factor (AIF) from mitochondria. Ectopic expression of DN-hTERT resulted in inhibition of telomerase activity, reduction of telomere length, decreased colony formation ability, and loss of tumorigenicity in nude mice. Moreover, DN-hTERT transfected HeLa cells with shortened telomeres were more susceptible to multiple chemotherapeutic agents and radiation. WT-hTERT transfected HeLa cells with longer telomeres exhibited resistance to radiation and chemotherapeutic agents. Our data demonstrate that elevated release level of cytochrome c and AIF from mitochondria might contribute to the enhanced apoptosis in DN-hTERT transfected HeLa cells after treatment with sodium butyrate. Inhibition of telomerase might serve as a promising adjunctive therapy combined with conventional therapy in cervical cancer.

Animals↗
PubMed1979

Histone deacetylation in nuclei isolated from hepatoma tissue culture cells. Inhibition by sodium butyrate.

Nuclei from hepatoma tissue culture (HTC) cells were isolated by standard methods and incubated in media commonly used for nuclease digestions (DNAase I and micrococcal nuclease) and for in vitro RNA synthesis. During the incubation, histones can be deacetylated from both control cells and cells treated with 6 mM sodium butyrate to enhance the levels of histone acetylation. Deacetylation of histone is much more apparent in nuclei isolated from sodium butyrate-treated cells. Inclusion of 6 mM sodium butyrate in the incubation medium effectively inhibits the endogenous deacetylase activity acting on histones H3 and H4, whereas sodium acetate at the same concentration has very little inhibitory effect.

Acetates↗
PubMed1994

Selection of a highly tumorigenic breast cancer cell line sensitive to estradiol to evidence in vivo the tumor-inhibitory effect of butyrate derivative Monobut-3.

To increase butyric acid mean residence time in vivo, we have produced a stable butyric acid derivative. Monobut-3. Recently, we have described that Monobut-3 is able to induce phenotypic changes in human mammary tumor cells in vitro. In this study, we explore the in vivo effect of Monobut-3. Human breast tumor cell-lines did not easily produce in vivo xenografts, thus, MCF-7 cells required exogenous 17 beta-estradiol to grow and to form in vivo xenografts. To evaluate in vivo and anti-tumor effects of monobut-3 without exogenous 17 beta-estradiol addition, we have established MCF-7 variant cells, highly tumorigenic MCF-7vht, in which transfection of ras oncogene induced a bypass of estrogen requirement but did not delete the presence of functional estrogen receptor (ER). Monobut-3 inhibited growth of this variant by about 90% at 4 mM and reduced 17 beta-estradiol cell growth stimulation. In vivo, in absence of 17 beta-estradiol, 2 mg per mouse monobut-3 decreased tumor take by about 25% and tumor growth by about 50% in nude mice. This is the first experimental demonstration of an in vivo antitumoral effect of a butyric acid derivative alone on a solid human tumor. These data suggest that this compound does not only act by reducing of 17 beta-estradiol stimulation but it also has an 17 beta-estradiol-independent effect. Absence of toxicity and its antiproliferative effects could suggest its use in clinical treatment of well differentiated carcinoma.

Animals↗
PubMed1992

alpha-Naphthyl butyrate carboxylesterase activity in human and rat nasal tissue.

Carboxylesterase activity in the rat nasal mucosa plays an important role in the response of this tissue to certain toxic inhaled esters. We have examined this activity in extracts of both Fischer-344 rat and human nasal tissue using the substrate alpha-naphthyl butyrate, the same substrate as that used for histochemical analysis of this activity. We find substantially higher activity in rat nasal extracts than in human nasal extracts. The Michaelis constant (Km), however, is approximately the same for both activities and is significantly less than that reported for rat nasal carboxylesterase activity using dibasic esters as a substrate. p-Nitrophenyl butyrate is a competitive inhibitor of the rat alpha-naphthyl butyrate esterase, but surprisingly has no effect on the human activity. The assay reported here should prove a powerful tool in the development of a valid in vitro nasal toxicity assay system that uses cultured rat or human cells expressing carboxylesterase activity.

Acrylates↗
PubMed1975

Butyric acid, a potent inducer of erythroid differentiation in cultured erythroleukemic cells.

Butyric acid is an unusually potent inducer of erythroid differentiation in cultured erythroleukemic cells. It is effective at one hundredth the concentration required of dimethylsulfoxide, a most effective inducing agent. Studies using a variety of analogues and metabolites suggest that the structural features of butyric acid are rather stringently required for induction. This effect is considered in view of the fact that butyric acid is a naturally occurring fatty acid, is effective in relatively low concentrations, and is widely used to form derivatives of cAMP.

Butanols↗