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Polyamine Levels (polyamine + level)
Selected AbstractsPolyamine metabolism in barley reacting hypersensitively to the powdery mildew fungus Blumeria graminis f. sp. hordeiPLANT CELL & ENVIRONMENT, Issue 3 2002T. Cowley Abstract Polyamine levels and activities of enzymes of polyamine biosynthesis and catabolism were examined in the barley cultivar Delibes (Ml1al + Ml(Ab)) reacting hypersensitively to the powdery mildew fungus, Blumeria graminis f. sp. hordei (race CC220). Levels of free putrescine and spermine and of conjugated forms of putrescine, spermidine and spermine were greatly increased 1,4 d following inoculation of barley with the powdery mildew. These changes in polyamine levels were accompanied by elevated activities of the polyamine biosynthetic enzymes ornithine decarboxylase (ODC), arginine decarboxylase (ADC) and S -adenosylmethionine decarboxylase (AdoMetDC) and the polyamine catabolic enzymes diamine oxidase (DAO) and polyamine oxidase (PAO). Activities of two enzymes involved in conjugating polyamines to hydroxycinnamic acids, putrescine hydroxycinnamoyl transferase (PHT) and tyramine feruloyl-CoA transferase (TFT) were also examined and were found to increase significantly 1,4 d after inoculation. The possibility that the increased levels of free spermine, increased polyamine conjugates, and increased DAO and PAO activities are involved in development of the hypersensitive response of Delibes to powdery mildew infection is discussed. [source] Cell culture analysis of the regulatory frameshift event required for the expression of mammalian antizymesGENES TO CELLS, Issue 11 2001Michael T. Howard Background Antizyme is a critical regulator of cellular polyamine levels due to its effect on polyamine transport and its ability to target ornithine decarboxylase for degradation. Antizyme expression is autoregulatory, through dependence on an unusual +1 translational frameshift mechanism that responds to polyamine levels. Results HEK293 cells were depleted of polyamines by treatment with an ornithine decarboxylase inhibitor, difluoromethylornithine (DFMO), and grown in the presence or absence of exogenous polyamines prior to the analysis of ribosomal frameshifting levels. Results obtained using an optimized dual luciferase assay system reveal a 10-fold dynamic range of frameshifting, which correlates positively with polyamine addition. Polyamine addition to cells, which have not been pre-treated with DFMO, also resulted in an increase in antizyme frameshifting but to a lesser degree (1.3 to 1.5-fold). In addition, the constructs with the 3, deletion were more responsive to stimulation by polyamine addition than those with the 5, deletion. Conclusions The observed regulation of antizyme frameshifting demonstrates the efficiency of a polyamine homeostatic mechanism, and illustrates the utility of a quantifiable cell-based assay for the analysis of polyamines or their analogues on translational frameshifting. [source] The Influence of Lactobacillus brevis on Ornithine Decarboxylase Activity and Polyamine Profiles in Helicobacter pylori -Infected Gastric MucosaHELICOBACTER, Issue 2 2004Michele Linsalata ABSTRACT Background., Functional probiotics may prevent Helicobacter pylori infection, and some evidence suggests that they also possess antitumor properties. Lactobacillus brevis (CD2) is a functional Lactobacillus strain with peculiar biochemical features, essentially related to the activity of arginine deiminase. This enzyme catalyzes the catabolism of arginine and affects the biosynthesis of polyamines (putrescine, spermidine, and spermine). Polyamines are polycations found in high concentrations in both normal and neoplastic cells. Our aims were: 1, to assess whether oral administration of L. brevis (CD2) affects H. pylori survival in the human gastric mucosa; 2, to evaluate the effects of L. brevis (CD2) on polyamine biosynthesis in gastric biopsies from H. pylori- positive patients. Materials and Methods., For 3 weeks before endoscopy, 22 H. pylori- positive dyspeptic patients randomly received (ratio 1 : 1) high oral doses of L. brevis (CD2) or placebo. Before and after treatment, H. pylori infection was determined by urea breath test (UBT). In gastric biopsies, ornithine decarboxylase activity and polyamine levels were, respectively, evaluated by a radiometric technique and high-pressure liquid chromatography (HPLC). Results.,L. brevis (CD2) treatment did not eradicate H. pylori. However, a reduction in the UBT delta values occurred, suggesting a decrease in intragastric bacterial load. Significantly, L. brevis (CD2) induced a decrease in gastric ornithine decarboxylase activity and polyamine levels. Conclusions., Our data support the hypothesis that L. brevis (CD2) treatment decreases H. pylori colonization, thus reducing polyamine biosynthesis. Alternatively, the arginine deiminase activity following L. brevis (CD2) administration might cause arginine deficiency, preventing polyamine generation from gastric cells. [source] Polyamine metabolism and cancerJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 2 2003Thresia Thomas Abstract Polyamines are aliphatic cations present in all cells. In normal cells, polyamine levels are intricately controlled by biosynthetic and catabolic enzymes. The biosynthetic enzymes are ornithine decarboxylase, S-adenosylmethionine decarboxylase, spermidine synthase, and spermine synthase. The catabolic enzymes include spermidine/spermine acetyltransferase, flavin containing polyamine oxidase, copper containing diamine oxidase, and possibly other amine oxidases. Multiple abnormalities in the control of polyamine metabolism and uptake might be responsible for increased levels of polyamines in cancer cells as compared to that of normal cells. This review is designed to look at the current research in polyamine biosynthesis, catabolism, and transport pathways, enumerate the functions of polyamines, and assess the potential for using polyamine metabolism or function as targets for cancer therapy. [source] Polyamine metabolism in barley reacting hypersensitively to the powdery mildew fungus Blumeria graminis f. sp. hordeiPLANT CELL & ENVIRONMENT, Issue 3 2002T. Cowley Abstract Polyamine levels and activities of enzymes of polyamine biosynthesis and catabolism were examined in the barley cultivar Delibes (Ml1al + Ml(Ab)) reacting hypersensitively to the powdery mildew fungus, Blumeria graminis f. sp. hordei (race CC220). Levels of free putrescine and spermine and of conjugated forms of putrescine, spermidine and spermine were greatly increased 1,4 d following inoculation of barley with the powdery mildew. These changes in polyamine levels were accompanied by elevated activities of the polyamine biosynthetic enzymes ornithine decarboxylase (ODC), arginine decarboxylase (ADC) and S -adenosylmethionine decarboxylase (AdoMetDC) and the polyamine catabolic enzymes diamine oxidase (DAO) and polyamine oxidase (PAO). Activities of two enzymes involved in conjugating polyamines to hydroxycinnamic acids, putrescine hydroxycinnamoyl transferase (PHT) and tyramine feruloyl-CoA transferase (TFT) were also examined and were found to increase significantly 1,4 d after inoculation. The possibility that the increased levels of free spermine, increased polyamine conjugates, and increased DAO and PAO activities are involved in development of the hypersensitive response of Delibes to powdery mildew infection is discussed. [source] Increased hair polyamine levels in patients with alzheimer's diseaseANNALS OF NEUROLOGY, Issue 1 2001Man Ho Choi MSc No abstract is available for this article. [source] | |||||||||||||