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The levels of putrescine and spermine in mouse brain were rather constant at different times of day, as were the activities of ornithine and S-adenosyl- l-methionine decarboxylases. Contrary to an earlier report, the level of spermidine was found to be relatively constant. A possibly significant feature in the present results was the steady decline during the light period and rise during darkness of cerebral spermidine and spermine levels, the differences between maximum and minimum being about 15% for both compounds. [ABSTRACT FROM AUTHOR]

A cytotoxic drug (vincristine, VC) was incorporated into low-density lipoprotein (LDL) and given to cancer patients for the first time by repeated intravenous injection. Individuals presenting with ovarian or endometrial cancer received four or five weekly doses of 1.4 mg/m2 LDL/VC. The uptake of LDL/VC by the adrenal cortex and the liver was minimised by concurrent administration of prednisolone and chenodeoxycholic acid. No febrile, allergic or other reaction attributable to the LDL occurred, and no side effect on haemopoietic, adrenal or liver functions was observed. The neurotoxic side effects commonly seen during VC therapy appeared to be reduced. These results suggest that directed cytotoxic therapy might be achieved in humans through the use of LDL as a carrier. Thus, dose-range and comparative studies using LDL/VC vs VCSO4 are warranted in malignancies in which treatment with the latter drug has been established. [ABSTRACT FROM AUTHOR]

The adhesion of pathogens to host tissues is the requirement for the initiation of the majority of infectious diseases. It was shown recently that the binding of Neisseria meningitidis pili to immobilized human epithelial cells is inhibited by molecular size fractions (10-100 kDa) of berry juices. Additionally, the isolated meningococcal pili bound to polyphenolic fractions of berry juices. The present study investigated the antiadhesive effects of berry juice polyphenolics against living meningococcal bacteria in a human epithelial cell culture model. The ability of bilberry, cranberry, crowberry and lingonberry juice polyphenolic fractions to inhibit the attachment of N. meningitidis bacteria to HEC-1B human epithelial cells in a cell culture model was examined. The antibacterial effect of the fractions was tested using a microtiter broth microdilution assay. The most effective adhesion inhibition of 75% was achieved with cranberry juice polyphenolic fraction followed by crowberry (63%), bilberry (63%) and lingonberry (57%) juice polyphenolic fractions. Bacterial survival rates after incubation with the fractions varied between 75-100%. The present results suggest berry juice polyphenols as inhibitors of adherence of N. meningitidis. Thus the binding of meningococci to berry juice polyphenols might be protective for the host against the infection., (Copyright © 2010 John Wiley & Sons, Ltd.)

Antiadhesion therapy is a promising approach to the fight against pathogens. Antibiotic resistance and the lack of effective vaccines have increased the search for new methods to prevent infectious diseases. Previous studies have shown the antiadhesion activity of juice from cultivated cranberries (Vaccinium macrocarpon Ait.) against bacteria, especially E. coli. In this study, the binding of two streptococcal strains, Streptococcus pneumoniae and Streptococcus agalactiae, to molecular size fractions (FI, FII and FIII, <10 kDa, 10-100 kDa, and >100 kDa, respectively) of berries and berry and fruit juices from 12 plant species were studied using a microtiter well assay. For Streptococcus suis a hemagglutination inhibition assay was used. In general, binding activity was detected especially to wild cranberry (Vaccinium oxycoccos L.) and to other Vaccinium species. S. pneumoniae cells bound most to cranberry juice fraction FI and S. agalactiae cells to cranberry fraction FIII. Hemagglutination induced by S. suis was most effectively inhibited by cranberry fraction FII. NMR spectra of some characteristic active and non-active fractions were also measured. They indicate that fractions FII and FIII contained proanthocyanidins and/or other phenolic compounds. The results suggest Vaccinium berries as possible sources of antiadhesives against bacterial infections.

Blocking bacterial adhesion to host surfaces provides novel potential to control infections. The present study was directed to binding and inhibitory activity of different fresh berries and berry and fruit juices against Neisseria meningitidis . Berries and juices were fractionated according to their molecular size into three fractions. A microtiter well assay for binding of N. meningitidis pili to berry and juice fractions was constructed. In addition, adhesion inhibition to human epithelial cells (HEC-1B) was tested. The active fractions were then subfractionated by employing solid-phase extraction. Subfractions were characterized by RP-HPLC-DAD, and the pili binding was evaluated by using microtiter well binding assay. Binding and inhibitory activity were detected to bilberry, cranberry, lingonberry, and crowberry fractions, which contained anthocyanins or a mixture of proanthocyanidins and flavonols. Thus, the findings identify several previously unknown binding and inhibitory activities and may suggest Vaccinium berries and crowberry as promising sources against meningococcal adherence.

Several members of the widespread alphavirus group are pathogenic, but no therapy is available to treat these RNA virus infections. We report here a quantitative assay to screen for inhibitors of Semliki Forest virus (SFV) replication, and demonstrate the effects of 29 nucleosides on SFV and Sindbis virus replication. The anti-SFV assay developed is based on a SFV strain containing Renilla luciferase inserted after the nsP3 coding region, yielding a marker virus in which the luciferase is cleaved out during polyprotein processing. The reporter-gene assay was miniaturized, automated and validated, resulting in a Z' value of 0.52. [3H]uridine labeling for 1 h at the maximal viral RNA synthesis time point was used as a comparative method. Anti-SFV screening and counter-screening for cell viability led to the discovery of several new SFV inhibitors. 3'-amino-3'-deoxyadenosine was the most potent inhibitor in this set, with an IC50 value of 18 microM in the reporter-gene assay and 2 microM in RNA synthesis rate detection. Besides the 3'-substituted analogues, certain N6-substituted nucleosides had similar IC50 values for both SFV and Sindbis replication, suggesting the applicability of this methodology to alphaviruses in general.

An enzymatic transglycosylation of purine heterocyclic bases employing readily available natural nucleosides or sugar-modified nucleosides as donors of the pentofuranose fragment and recombinant nucleoside phosphorylases as biocatalysts has been investigated. An efficient enzymatic method is suggested for the synthesis of purine nucleosides containing diverse substituents at the C6 and C2 carbon atoms. The glycosylation of N(6)-benzoyladenine and N(2)-acetylguanine and its O(6)-derivatives is not accompanied by deacylation of bases.

Milk oligosaccharides have been shown to interfere with adhesion of many pathogens to host mucosal surfaces. Characterization of the adhesion mechanisms of the bacteria to host cell surface is needed to develop novel functional food, infant formulas, and anti-infective drugs. Adhesion of Neisseria meningitidis, a human specific pathogen causing meningitis and septicemia, is not completely understood but is mediated by type IV pili. Here, we developed a microtiter well pili binding assay to investigate the binding activities of N. meningitidis isolated type IV pili to different glycoproteins. Pili binding activities to bovine thyroglobulin and human salivary agglutinin but not to chicken ovalbumin were present. Inhibition of these binding activities was demonstrated by fractionated human or bovine milk oligosaccharides. The binding of neisserial pili to bovine thyroglobulin was most effective and was clearly inhibited by human milk neutral or bovine milk acidic oligosaccharides.

Two mass spectrometry methods, high-performance liquid chromatography combined on-line with electrospray ionization mass spectrometry (HPLC-ESI-MS) and electron-capture (EC) dissociation tandem mass spectrometry (MS-MS), were applied for structural analysis of bovine and human osteocalcins. Osteocalcin contains gamma-carboxyglutamic acid (Gla) residues, which bind metal ions, among its amino acids. Ethylenediaminetetraacetic acid (EDTA) was added to all samples in order to chelate bound metal ions. After elimination of interfering metal ions MS spectra became uncomplicated to interpret. EDTA is incompatible with ESI and it was removed from samples using either on-line HPLC or micropurification method. The number of Gla residues varies in osteocalcin. These subforms, which contain different amounts of Gla residues, were separated using the HPLC-ESI-MS method. In order to determine locations of Gla residues in human osteocalcin, which contained two Gla residues, dissociation MS-MS method was successfully applied.

A screening system was set up to study the effects of drugs on cytokine secretion by macrophages in vitro. The system is based on the murine macrophage-like cell line RAW 264, which can be activated with lipopolysaccharide (LPS) to produce cytokines. The responsiveness of the RAW 264 cells was outlined by challenging them with different concentrations of LPS for 6 or 24 h. Substantial time- and dose-dependent increases were recorded for interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF alpha) secretions. A general procedure was established to construct time-resolved fluoroimmunoassays (TRFIA) from commercial immunochemicals produced originally for enzyme immunoassays. Practical measuring ranges of the non-competitive assays were 100 pg/ml-10 ng/ml for IL-1 beta and TNF alpha and 10 pg/ml 5 for IL-6 and IL-5. The interleukin-5 (IL-5) assay was set up for unrelated human studies, but the others were used in the characterization of RAW 264 cytokine secretion. An immunosuppressive effect with dexamethasone phosphate could be achieved and recorded in the model system. Thus, the system offers a simple and easy-to-use model for screening immunomodulatory effects of drugs on the cytokine secretion of macrophages.

Purpose: In order to evaluate the possible antiinflammatory action of bisphosphonates, the effect of the drugs on the secretion of proinflammatory cytokines (IL-1 beta, IL-6 and TNF alpha) from macrophages was studied. Liposomes or high concentration of extracellular calcium was used to enhance the intracellular delivery of bisphosphonates., Methods: RAW 264 cells were used as macrophage model, and they were induced with lipopolysaccharide to produce the cytokines. The cytokine concentrations in the culture supernatants were measured with time-resolved fluoroimmunoassay., Results: As a free drug, clodronate and pamidronate, but not etidronate, inhibited LPS-stimulated secretion of the cytokines from macrophage-like RAW 264 cells. Low concentrations of pamidronate, however, induced the IL-6 secretion, and the cytokine inhibitory action at the higher concentrations of pamidronate was attributed to cytotoxicity of the compound. The cytokine induction or toxic effects were not observed with clodronate or etidronate. When the drugs were encapsulated in negatively charged unilamellar liposomes, the inhibitory potency of both clodronate and etidronate enhanced by a factor of 10-20, while that of pamidronate was not increased. The complex formation of bisphosphonates with extracellular calcium, although enhancing the uptake of the compounds by macrophages, did not considerably increase their cytokine inhibitory potency., Conclusions: Bisphosphonates have inhibitory action on cytokine secretion by macrophages. The non-cytotoxic cytokine inhibition by liposome encapsulated clodronate could be beneficial in local inflammatory diseases, where the inflammation is sustained by the excessive amounts of inflammatory cytokines produced by activated macrophages.

Effect of liposome-encapsulated and free clodronate on the IL-6 and TNF production by macrophages was studied using RAW 264 cell line as a macrophage model, and dissociation-enhanced lanthanide fluoroimmunoassay (DELFIA) for analysis of secreted cytokines. LPS-stimulated RAW 264 cells proved to produce notable amounts of these two cytokines, and DELFIA was sensitive and reliable method for analysis. Liposome-encapsulated clodronate inhibited the production of both cytokines, IL-6 being affected more than TNF, and the effect was mostly due to the drug itself, not to liposomal lipid. More than ten times higher concentration of free clodronate than liposomal clodronate was needed to inhibit cytokine production. This is the first report on the cytokine inhibitory property of clodronate, and the results support the idea of the use of liposomal clodronate as a macrophage suppressive agent in autoimmune diseases.

Fragmentation of protonated molecular ions produced from catharanthine, tabersonine, ajmalicine and serpentine in a high-performance liquid chromatography (HPLC) thermospray ion source was studied. Collision-induced dissociation (CID) of the compounds was achieved by merely increasing the repeller potential; i.e. no discharge current was applied and filament was not on. Proportion of fragments to the protonated molecular ions increased with the potential at the 180-350 V range studied, but overall yield of detected ions decreased at the higher voltages in all cases. Comparison of fragments produced in the thermospray CID with those derived from the protonated molecular ions by colliding with argon in a triple-stage quadrupole instrument showed that the fragmentation is very similar in both cases. An analytical application for identifying the alkaloids from plant cell culture material by HPLC/mass spectrometry using the thermospray CID is described.

The uptake, catabolism, and release of H-labeled 1-aminooxy-3-aminopropane, a new putrescine analog shown to be a potent polyamine antimetabolite, into and from baby hamster kidney cells (BHK21/C13) were studied. The results show that [3H]-1-aminooxy-3-aminopropane (APA) is not concentrated in the cell, does not compete with polyamines for transport and reveals no difference in uptake between polyamine-depleted and control cells. After a 12-h culture, 60% of APA was recovered intact in the culture media. At this time point, only 30% of the intracellular radioactivity was intact APA, showing that the drug is catabolized in the cells. This intracellular ratio persisted throughout the 4-day culture period. The metabolites of APA were not characterized further. The results indicate that the drug is not recognized as a polyamine by the cells and does not replace or interfere with the polyamines in cellular functions. Thus, its potent affinity to ornithine decarboxylase and spermidine synthase is likely to be due to close structural similarity with the intermediates formed in these reactions. This has implications for the mechanisms involved.

Hydrodynamic voltammograms for indole and five indole alkaloids with different amino functions were obtained in order to evaluate the applicability of high-performance liquid chromatography (HPLC) with coulometric detection to these compounds. With the exception of serpentine, which has a quaternary nitrogen in its structure, all the compounds were oxidised and gave net signals of greater than 25 nA pmol(-1) at potentials of between +0.2 and +0.85 V versus a solid Pd electrode in an acetate-buffered (pH 6.5) water-methanol-acetonitrile system. An HPLC assay for quantifying picomole amounts of catharanthine and ajmalicine in Catharanthus roseus cell culture samples is described.

Eleven structural analogs with norharmane (9H-pyrido [3, 4-b] indole) as the basic structure were used to study structure-activity relations of adenosyl-methionine decarboxylase inhibition by this type of compounds. All analogs with an intact or 3,4-dihydrogenated pyrido ring inhibited the enzyme competitively with apparent Kis at the micromolar range, but complete hydrogenation of the pyrido moiety abolished the inhibition. This indicates that a suitable arrangement of pi-electrons is an essential structural feature in the process. Strongest inhibitors (Ki approximately 10-5M) were compounds methoxy or hydroxy groups in positions 6 or 7 of the indole moiety, suggesting that polarizing groups containing atoms with free electron pairs also are important in the interaction. The results offer a new viewpoint when action mechanisms of the known adenosylmethionine decarboxylase inhibitors are evaluated and they may prove useful when new inhibitors to the enzyme are designed.

It has been reported in several recent studies that the manipulation of cerebral 4-aminobutyric acid (GABA) level results in unexpected changes in the cerebral polyamine metabolism in vivo. The mechanisms behind these interactions have remained unknown. The present results show that the changes in polyamine metabolism are not limited to the brain, but are observable also in the liver, which served as a peripheral reference tissue. Different types of responses in the activities of the polyamine-synthesizing enzymes, ornithine decarboxylase and adenosylmethionine decarboxylase, were observed after increasing the cerebral GABA concentration of mice with varying doses of two GABA transaminase inhibitors, gabaculine and ethanolamine-O-sulphate. The time course of the significant changes in the enzyme activities showed significant correlation between the brain and liver. The possibility of direct effects of the drugs on liver was excluded by injecting them intracerebroventricularly, and by performing control experiments with equal doses given peripherally. It is concluded that the observed changes in the polyamine metabolism of liver are produced through centrally mediated humoral regulation, and that the corresponding changes in the brain are obviously due to the same factor or factors, since they are significantly correlated to the changes in liver.

Intraperitoneal injection of chlorpromazine and imipramine increases mouse brain ornithine decarboxylase but decreases S-adenosyl-L-methionine decarboxylase activity. Maximal effect was obtained 6-8 hr after treatment at which time single dose of chlorpromazine (50 mg/kg) stimulated ornithine decarboxylase activity 7-fold and decreased S-adenosylmethionine decarboxylase activity to 50% from the control level. Correspondingly, ornithine decarboxylase activity was 5.5 times higher than the control value and S-adenosylmethionine decarboxylase activity about 40% from that after imipramine injection (80 mg/kg). The possible dependence of the enzyme responses on adrenergic receptors was studied using alpha-adrenoceptor antagonist, phentolamine, and beta-adrenoceptor antagonist, propranolol, concurrently with chlorpromazine and imipramine. The stimulation of ornithine decarboxylase but not the inhibition of S-adenosylmethionine decarboxylase could be abolished by propranolol (10 mg/kg), whereas phentolamine (10 mg/kg) slightly increased ornithine decarboxylase activity even when given alone. This suggests that beta- but not alpha-adrenergic mediation is involved in the stimulation of mouse brain ornithine decarboxylase activity and that brain ornithine and S-adenosylmethionine decarboxylase activities are independently regulated. When chlorpromazine and imipramine were tested in vitro, both of them turned out to have an inhibitory effect on S-adenosylmethionine decarboxylase. The former caused 50% inhibition at a concentration of 1 mM and the latter at 2 mM. Preliminary tests suggest that the type of inhibition is noncompetitive for both of them.

The effects of chlorpromazine, imipramine, thioridazine, chlorprothixene, amitriptyline, desipramine and triflupromazine on adenosylmethionine decarboxylase purified from rat liver have been studied. The compounds caused competitive inhibition of the enzyme at 10(-5) - 10(-3) M concentrations. For chlorprothixene and triflupromazine the inhibition was linear, while the other drugs showed increasing, nonlinear inhibition at higher concentrations. Apparent Ki's for the compounds were between 6.8 X 10(-5) M (for chlorprothixene) and 6.4 X 10(-4) M (for desipramine). Inhibition of 50% under optimal assay conditions was achieved between drug concentrations of 1.3 X 10(-4) M (thioridazine) and 1.3 X 10(-3) M (imipramine).

A rapid and precise method for the determination of fat-soluble vitamins from a water-based multivitamin mixture was developed utilizing solid-phase extraction and reversed-phase high-performance liquid chromatography (HPLC). Cholecalciferol, alpha-tocopherol acetate, and retinol palmitate were extracted in a single stage from the matrix using Bond Elut C18 columns. The vitamins were then chromatographed on a Hypersil 5-microns C18 column, using a water:methanol gradient, and quantified simultaneously using individual UV absorption maxima. The recovery of added analytes varied from 92.6 to 100.6%. The assay coefficient of variation was 1.7-2.7%. The sample preparation method and HPLC assay described here are practical for pharmaceutical quality control purposes.

We have previously shown that treatment of T lymphocytes with mitogenic ligands induces a rapid activation of ornithine decarboxylase (ODC) through a mechanism that is independent of protein synthesis but requires energy and an intact cytoskeleton. Here we show by immunoprecipitation experiments and by chemical analyses that ODC is covalently linked to the cell membrane by inositol. Treatment of sonicated cells with a phosphatidylinositol-specific phospholipase C from B. thuringiensis caused a rapid 3-fold increase in ODC activity. Similar treatment of intact cells had no effect, suggesting that the ODC is attached to the cytoplasmic surface of the membrane. We conclude that ODC release and activation occur by a novel mechanism involving phosphatidylinositol breakdown following ligand-receptor interaction.

An enzyme-linked immunosorbent assay for vincristine was developed, based on a new procedure for synthesizing the hapten-protein conjugate. In both the immunogen and the enzyme tracer a spacer group was introduced between the hapten and protein, and the vincristine was coupled at a site far from its functional groups. The antibody produced proved to be exceptionally specific as compared with previous immunoassays for bis-indole alkaloids. Thousandfold antibody dilutions could be used and samples at the femtomole range were assayable. Applications of the method to patient plasma samples and to plant material are described.