PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “THIOGLYCOLLIC ACID”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources

The glycosaminoglycans in cultures of stimulated rat peritoneal macrophages. 1. Pattern and biosynthesis of glycosaminoglycans.

Macrophages produce and secrete proteoglycans. They are involved in inflammation and may contribute to the glycosaminoglycans (GAG) and proteoglycans (PG) characteristic of the inflamed area. This possible contribution was studied with rat peritoneal macrophages (pMP) in vitro. The total amount, composition, and neosynthesis of the GAG (as the main constituents of PG) were determined in cultured pMP of normal rats or rats pretreated with casein, BCG, thioglycolate or carrageenan. Partly the stimulated pMP were further activated with LPS or PMA. The rat pMP contained non-sulfated GAG, chondroitin sulfate and heparan sulfate but no dermatan sulfate. The GAG amount per cell increased with duration of the culture. In most cases the final level of GAG roughly corresponded to that of 12 micrograms hexuronic acid per 10(6) cells. It was lower after BCG stimulation (25%) and higher in pMP stimulated by both casein and LPS (200%). The average percentage of the GAG secreted (40%) was enhanced with pMP stimulated by carrageenan (87%) or casein plus LPS (69%). The pattern of the GAG in cultural media, cell coat and cells differed markedly. Thus the cell coat contained a higher amount of heparan sulfate. Differences due to stimulation were mainly seen in the reduced sulfation of the CS-proteoglycan secreted (casein-, BCG-pMP). According to studies on the incorporation of 35S-sulfate and 3H-acetate the GAG of the cell coat are less labeled and more conservative. The bulk of newly synthesized GAG/PG is secreted. This secretion appears an important property of macrophages the cause of which is speculative.

Acetates↗

Dialkyl 3,3'-thiodipropionate and dialkyl 2,2'-thiodiacetate antioxidants by lipase-catalyzed esterification and transesterification.

Medium- and long-chain dialkyl 3,3'-thiodipropionate antioxidants such as dioctyl 3,3'-thiodipropionate, didodecyl 3,3'-thiodipropionate, dihexadecyl 3,3'-thiodipropionate, and di-(cis-9-octadecenyl) 3,3'-thiodipropionate were prepared in high yield by lipase-catalyzed esterification and transesterification of 3,3'-thiodipropionic acid and its dimethyl ester, respectively, with the corresponding medium- or long-chain 1-alkanols, i.e., 1-octanol, 1-dodecanol, 1-hexadecanol, and cis-9-octadecen-1-ol, in vacuo (80 kPa) at moderate temperatures (60-80 degrees C) without solvents. Immobilized lipase B from Candida antarctica (Novozym 435) was the most active biocatalyst for the preparation of medium- and long-chain dialkyl 3,3'-thiodipropionates showing enzyme activities up to 1489 units/g, whereas the immobilized lipases from Rhizomucor miehei (Lipozyme RM IM) and Thermomyces lanuginosus (Lipozyme TL IM) were by far less active ( approximately 10 enzyme units/g). Maximum conversions to dialkyl 3,3'-thiodipropionates were as high as 92-98% after 4 h of reaction time. Similarly, dihexadecyl 2,2'-thiodiacetate was prepared in high yield using 2,2'-thiodiacetic acid or diethyl 2,2'-thiodiacetate and 1-hexadecanol as the starting materials and Novozym 435 as the biocatalyst.

Antioxidants↗

Isolation and some observations of the properties of a bovine neurohypophysial milk-ejecting factor.

A substance possessing milk-ejecting activity has been isolated from an acetone powder preparation of bovine posterior pituitary glands by Sephadex G-25 chromatography of the neurophysin-neurohypophysial hormone complex. While the material possessed an oxytocic activity of 2.8 IU/mg as measured on the isolated rat uterus, the milk-ejecting activity was more than three fold greater, 9.6 IU/mg. The peptide had an antidiuretic activity of 0.133 IU/mg and a pressor activity of 0.083 IU/mg. Neither the uterine-stimulating action nor the pressor activity was destroyed by incubating the peptide with 0.01 M sodium thioglycollate at 65 degrees C for 5 min. The oxytocic activity was antagonized neither by 1.4 X 10(-6) M atropine nor 3.3 X 10(-7) M phenoxybenzamine.

Amino Acids↗

Mouse and human GTPBP2, newly identified members of the GP-1 family of GTPase.

We earlier identified the GTPBP1 gene which encodes a putative GTPase structurally related to peptidyl elongation factors. This finding was the result of a search for genes, the expression of which is induced by interferon-gamma in a macrophage cell line, THP-1. In the current study, we probed the expressed sequence tag database with the deduced amino acid sequence of GTPBP1 to search for partial cDNA clones homologous to GTPBP1. We used one of the partial cDNA clones to screen a mouse brain cDNA library and identified a novel gene, mouse GTPBP2, encoding a protein consisting of 582 amino acids and carrying GTP-binding motifs. The deduced amino acid sequence of mouse GTPBP2 revealed 44.2% similarity to mouse GTPBP1. We also cloned a human homologue of this gene from a cDNA library of the human T cell line, Jurkat. GTPBP2 protein was found highly conserved between human and mouse (over 99% identical), thereby suggesting a fundamental role of this molecule across species. On Northern blot analysis of various mouse tissues, GTPBP2 mRNA was detected in brain, thymus, kidney and skeletal muscle, but was scarce in liver. Level of expression of GTPBP2 mRNA was enhanced by interferon-gamma in THP-1 cells, HeLa cells, and thioglycollate-elicited mouse peritoneal macrophages. In addition, we determined the chromosomal localization of GTPBP1 and GTPBP2 genes in human and mouse. The GTPBP1 gene was mapped to mouse chromosome 15, region E3, and human chromosome 22q12-13.1, while the GTPBP2 gene is located in mouse chromosome 17, region C-D, and human chromosome 6p21-12.

Amino Acid Sequence↗

Design and synthesis of tricyclic compounds with enone functionalities in rings A and C: a novel class of highly active inhibitors of nitric oxide production in mouse macrophages.

Novel tricyclic compounds with enone functionalities in rings A and C, which were designed on the basis of the structure of a synthetic triterpenoid, 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid, have been synthesized. Among them, 10 shows high inhibitory activity (IC(50) = 1 nM level) against production of nitric oxide induced by interferon-gamma in mouse macrophages and is orally active at 15 mg/kg (once) in a preliminary in vivo study using mouse peritoneal inflammation induced by thioglycollate and interferon-gamma.

Animals↗

Alkaline phosphodiesterase I of cultured mouse peritoneal macrophages. Distribution between cell surface and cytoplasm, turnover rate, and effects of colchicine.

Mouse peritoneal macrophages were cultivated in vitro and analyzed for activity of alkaline phosphodiesterase I. The specific enzyme activity was 2 to 3 times higher in thioglycollate-elicited than in resident cells and raised slowly for at least 3 days of culture in both cell types. Following phagocytosis of polystyrene latex beads the enzyme activity remained unchanged. About 90% of the activity was lost by treatment of the cells with the diazonium salt of sulfanilic acid (DASA) for 30 min at 37 degrees C. At 4 degrees C the corresponding degree of inactivation was only 40 to 50%. This temperature-dependent variation in the accessibility of the enzyme to inactivation by DASA could be related to the high rate of endocytosis in macrophages. During a 30 min incubation with DASA at 37 degrees C, large amounts of surface membrane will be internalized and replaced from the interior of the cell. Surface membrane is thus transferred into intracellular membrane and vice versa. Moreover, these membranes will be exposed to DASA independent of their location at the start of incubation. At 4 degrees C no comparable membrane traffic will take place. Treatment of the cells with cycloheximide at concentrations that inhibited protein synthesis by 90% or more left the enzyme activity essentially unaltered, indicating a slow turnover rate. On the basis of these findings, it is suggested that about half of the alkaline phosphodiesterase I activity of cultured macrophages is located in the plasma membrane. The other half is believed to be present in endocytic vesicles, lysosomes, and other as yet unidentified organelles that participate in the circulation of membrane constituents between the plasma membrane and the interior of the cell.

Animals↗

Indole-3-acetic acid increases glutamine utilization by high peroxidase activity-presenting leukocytes.

Indole-3-acetic acid (IAA) is toxic for human tumor cells and in association with horseradish peroxidase (HRP) can be used as a new prodrug/enzyme combination for targeted cancer therapy. The toxic effect of IAA on neutrophils, macrophages and lymphocytes is associated with cell peroxidase activity, which is high in neutrophils and low in lymphocytes. The effect of IAA on glucose and glutamine metabolism in leukocytes presenting different peroxidase activities: neutrophils, thioglycollate-elicited macrophages and lymphocytes was investigated. A time-course effect (from 6 to 48 h in culture) of IAA on glucose and glutamine metabolism of neutrophils, thioglycollate-elicited macrophages, and lymphocytes was then carried out. Addition of IAA (0.25 mM) did not have a marked effect on glucose utilization and lactate formation by the three cell types but it raised glutamine consumption and glutamate production by neutrophils and macrophages. IAA had no effect on glutamine consumption and glutamate production by lymphocytes. A strong relationship was found between glutamine utilization (0.999) and glutamate production (0.999) and peroxidase activity. IAA did not change the activities of hexokinase, glucose-6-phosphate dehydrogenase, citrate synthase, lactate dehydrogenase, and phosphate-dependent glutaminase of 24 h cultured neutrophils and lymphocytes. The effect of IAA (1 mM) on glucose and glutamine metabolism was also investigated by 1 h incubated leukocytes in PBS. IAA did not affect glucose and glutamine metabolism of lymphocytes but enhanced glucose and glutamine metabolism by 1 h incubated neutrophils and thioglycollate-elicited macrophages. IAA caused a marked increase on oxygen consumption by neutrophils, which was more pronounced in the presence of the glutamine as compared to glucose. The stimulation of oxygen consumption leads to a reduction in NADH/NAD+ ratio that activates the flux of substrates through the Krebs cycle. Since glutamine is mainly metabolized through the left hand side of the Krebs cycle, a reduction in the redox state of the cells may accelerate the flux of substrates through glutaminolysis. The toxic results presented here show that the affect of IAA in association with peroxidase involves activation of glutamine metabolism.

Analysis of Variance↗

Capping revisited. I. Inhibition by some thiols.

The capping, but not the clustering (spotting), of membrane immunoglobulins and of other lymphocyte membrane macromolecules is inhibited when the medium contains some reducing agents, principally cysteine. The inhibition is easily reversible, being rather a retardation of capping than its blockage. The mechanism of inhibition is still unclear, but it definitely depends on the sulfhydryl moiety of the thiols.

Amino Acids↗

A synthetic analog of the 3-deoxy-D-manno-2-octulosonic acid disaccharide moiety of rough-type endotoxins does not bind to mouse peritoneal macrophages and human monocytes.

Strong evidence supports the concept that lipid A is the main biologically active region of endotoxins and is recognized by specific binding sites of different cell types. However, receptors for carbohydrates are also present on mononuclear phagocytes, and it has been suggested that one of these lectin-like proteins may be specific for the 3-deoxy-D-manno-2-octolosonic acid (Kdo) residues of endotoxins. To reexamine this hypothesis, we prepared a 125I-labeled conjugate consisting of a synthetic Kdo-2,4-Kdo disaccharide covalently linked to bovine serum albumin (125I-Kdo2-BSA). The Kdo disaccharide residues of this radiolabeled conjugate were fully accessible to a monoclonal antibody which reacts specifically with this epitope. However, 125I-Kdo2-BSA did not exhibit any detectable specific binding on thioglycolate-elicited mouse peritoneal macrophages or on human monocytes. Furthermore, the specific binding of biotin-labeled lipopolysaccharide derivatives to mouse macrophages and human monocytes was not inhibited by a soluble synthetic Kdo-2,4-Kdo-polyacrylamide copolymer or by a synthetic glycolipid consisting of an alpha-Kdo residue glycosidically linked to O-6 of allyl-4-O-phosphoryl-N-3-hydroxytetradecanoyl-beta-D-glucosaminide. These results indicate that binding sites specific for Kdo are not present (or not accessible) on the surface of mouse macrophages and human monocytes.

Animals↗

The development of a quantitative RIA for basic fibroblast growth factor using polyclonal antibodies against the 157 amino acid form of human bFGF. The identification of bFGF in adherent elicited murine peritoneal macrophages.

Polyclonal antibodies which have the capacity to neutralize the biological activity of basic fibriblast growth factor (bFGF) in vitro, have been raised in rabbits against the 157 amino acid form of bFGF purified from human placenta. In a dot blot assay the anti-bFGF antibodies do not recognize the acidic form of FGF (aFGF) with which the basic form shares significant amino acid sequence homology. As determined by immunoblotting, bFGF antibodies recognized only bFGF in a mixture of placentally derived heparin-binding proteins, demonstrating the specificity of these antibodies. Using the anti-human bFGF antibodies, we have developed a solid-phase competitive radioimmunoassay sensitive to 7.8 ng/ml (0.4 pmol/ml) for bFGF. aFGF does not compete with bFGF for binding to the antibodies in the radioimmunoassay even at 2.04 micrograms/ml. The specificity of the assay was further demonstrated by a lack of competition of cytochrome C, myoglobin, epidermal growth factor or bovine serum albumin with bFGF for binding to the antibodies. We have identified bFGF in extracts of adherent thioglycollate-stimulated mouse peritoneal macrophages by immunological criteria including the ability of the extract to compete with 125I-bFGF for binding to affinity-purified anti-human bFGF antibodies in the RIA and the ability of these antibodies in inhibit the bFGF-like biological activity of the macrophage extract.

Amino Acids↗

Evidence for a vagally mediated satiety signal derived from hepatic fatty acid oxidation.

To test the possibility that vagally mediated signals derived from hepatic fatty acid oxidation affect feeding, we investigated the influence of selective hepatic vagotomy on the acute hyperphagic effect of the fatty acid oxidation inhibitor 2-mercaptoacetate (MA) in rats kept on a medium fat diet (18% fat). An i.p. injection of MA (400 mumol/kg b.wt.) stimulated feeding in sham-vagotomized rats clearly more than in vagotomized rats. A high dose of MA (800 mumol/kg b.wt.) initially increased food intake in sham-vagotomized but not in vagotomized rats and later decreased food intake similarly in both surgical groups. MA retained its potency to stimulate feeding after an i.p. injection of atropine methylnitrate (5 mg/kg b.wt.). These results indicate that hepatic fatty acid oxidation provides a satiety signal that is mediated by vagal afferents.

Animals↗