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Roberto Pagani - One of the best experts on this subject based on the ideXlab platform.
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The influence of testosterone on Purine Nucleotide metabolism in rat liver.
Life Sciences, 1995Co-Authors: Maria Pizzichini, Daniela Vannoni, Roberto Leoncini, Enrico Marinello, Roberto PaganiAbstract:Abstract Purine Nucleotide metabolism was studied in rat liver by following the incorporation of 14C-formate into soluble Nucleotides, uric acid and RNA riboNucleotides. After castration, GMP formation was less than that of AMP, and Purine Nucleotide catabolism and RNA synthesis decreased. Testosterone administration did not modify GMP or AMP synthesis, but restored Purine Nucleotide catabolism and RNA production to normal values. These results demonstrate the influence of testosterone on Purine Nucleotide metabolism in a non-reproductive organ.
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Purine Nucleotide metabolism in lymphocytes of B-cell chronic lymphocytic leukemia patients
Biomedicine & Pharmacotherapy, 1995Co-Authors: Antonella Tabucchi, Daniela Vannoni, E. Dispensa, Filippo Carlucci, Roberto Leoncini, E. Consolmagno, Maria Pizzichini, Enrico Marinello, Roberto PaganiAbstract:Summary Purine Nucleotides were studied in human peripheral blood lymphocytes from normal subjects and patients with chronic B-cell lymphocytic leukemia (B-CLL). Nucleotide content was determined by high performance liquid chromatography (HPLC). The overall rate of Purine Nucleotide synthesis was measured following the incorporation of l4 C-formate into the Nucleotides of a lymphocytic suspension. Results indicate a substantially reduced rate of Purine Nucleotide metabolism.
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Purine Nucleotide content of lymphocytes from healthy subjects and asymptomatic HIV-1 seropositive patients.
Recenti progressi in medicina, 1991Co-Authors: Antonella Tabucchi, Filippo Carlucci, Enrico Marinello, Maria Carla Re, L. Bisozzi, Cacopardo F, Roberto PaganiAbstract:: The Purine Nucleotide content of lymphocytes of normal subjects and asymptomatic HIV-1 seropositive patients was analyzed by HPLC. An increase in IMP and a decrease in ADP, GDP, ATP and GPT were observed in the HIV-infected patients with respect to healthy subjects. The changes may depend on different factors and indicate that the virus influences Purine Nucleotide metabolism of the cell. The finding sheds light on the metabolic situation of the infected cell, and could be applied to monitoring the disease.
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Some Aspects of Purine Nucleotide Metabolism in Human Lymphocytes before and after Infection with HIV-1 Virus: Nucleotide Content
Advances in Experimental Medicine and Biology, 1991Co-Authors: Roberto Pagani, Antonella Tabucchi, Filippo Carlucci, Roberto Leoncini, E. Consolmagno, M. Molinelli, P. ValerioAbstract:The evaluation of intracellular metabolism of Purine Nucleotides is important in many conditions, during, for example, proliferation, or maturation of the cell -i.e. leukemia and SCID (= severe congenital immunodeficiency)- and can be studied following different procedures: 1) evaluation of Purine Nucleotide content (1); 2) incorporation of labelled precursors of the Purines, e.g. 14C-glycine or 14C-formate with kinetics based on biomathematical models (2); 3) assay of each individual enzymatic activity, involved in the various pathways of Purine Nucleotide metabolism, the de novo synthesis, the salvage pathway, and the Purine Nucleotide catabolism (2).
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Some aspects of Purine Nucleotide metabolism in lymphocytes of B-CLL.
Tumori, 1991Co-Authors: Antonella Tabucchi, Daniela Vannoni, Brunetta Porcelli, Lucia Terzuoli, Roberto Pagani, Roberto Leoncini, Maria Pizzichini, Enrico Marinello, E. DispensaAbstract:: The authors studied the behavior of some enzymes involved in Purine Nucleotide metabolism in human peripheral blood lymphocytes from normal and B-cell chronic lymphocytic leukemia subjects. Determinations were made with radiochemical methods associated with high performance liquid chromatography. Results indicated a marked increase in de novo Purine synthesis enzymes, particularly those of the "inosinic branch point". The latter were absent in normal lymphocytes, whereas they were well evident in leukemic lymphocytes, with the exception of AMP-S synthetase. Whereas the enzymes of the "salvage pathway" were spared in comparison to other proteins, those of the "catabolic pathway" significantly decreased. The authors discuss the possibility that such enzymes may be used as tumor markers.
Enrico Marinello - One of the best experts on this subject based on the ideXlab platform.
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Effect of testosterone on Purine Nucleotide metabolism in rat liver.
Hormone and Metabolic Research, 2004Co-Authors: Enrico Marinello, Daniela Vannoni, Brunetta Porcelli, Lucia Terzuoli, Roberto Leoncini, Resconi GAbstract:: In previous studies, we found that castration induced interesting morphological and biochemical changes in rat liver. For the present study, we have examined the effects of testosterone on the kinetics of Purine Nucleotide metabolism with the aim of determining the steps affected by testosterone deficiency. A biomathematical model of Purine Nucleotide metabolism was used to analyze the many reactions involved. The model simplifies Purine Nucleotide metabolism to four main steps: 1) de novo synthesis from PRPP to IMP; 2) the inosinic branch point from IMP to GMP or AMP; 3) catabolism of IMP, AMP and GMP to uric acid; 4) RNA and DNA formation from AMP and GMP. We evaluated rate constants from each step from variations in specific radioactivity of metabolites labelled with (14)C-formate, a precursor of de novo synthesis. The model was applied to the liver of normal and castrated rats before and after testosterone treatment. All four steps were slowed after castration, and were not completely restored by androgen administration. The model can give a clear representation of the kinetics of the reactions involved in the liver Nucleotide metabolism investigated here, and we propose that a similar approach could be useful whenever a quantitative evaluation of the results obtained in vivo after administration of labelled precursors is required.
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Purine Nucleotide metabolism: specific aspects in chronic lymphocytic leukemia lymphocytes
Biochimica et Biophysica Acta, 1997Co-Authors: Filippo Carlucci, C Di Pietro, Francesca Rosi, Maria Pizzichini, Enrico Marinello, Antonella TabucchiAbstract:Abstract The metabolism of Purine Nucleotides was studied in human peripheral blood lymphocytes from healthy subjects and patients with B-cell chronic lymphocytic leukemia. Nucleotide content was determined by HPLC. The rate of de novo synthesis of Purine Nucleotides was measured kinetically by following the incorporation of 14 C-formate into the Nucleotides of a lymphocyte suspension. The patterns of the main enzymes involved in Purine Nucleotide metabolism (those of the salvage pathway and catabolism) were estimated by a radiochemical method. Although the data expressed in relation to cells and protein showed some discrepancies, several common differences were evident in both cases. The main differences were an increase in NAD and IMP, a sharp decrease in 5′-nucleotidase activities and in total guanylate content and synthesis, and an increase in the A/G ratio in lymphocytes of patients with respect to controls. The changes in these parameters in CLL indicate an imbalance in Purine metabolism and may play a specific role in the biology of the leukemia cell. They are also potential biochemical markers of lymphoid malignancies and may be useful in chemotherapic applications. ©1997 Elsevier Science B.V. All rights reserved.
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The influence of testosterone on Purine Nucleotide metabolism in rat liver.
Life Sciences, 1995Co-Authors: Maria Pizzichini, Daniela Vannoni, Roberto Leoncini, Enrico Marinello, Roberto PaganiAbstract:Abstract Purine Nucleotide metabolism was studied in rat liver by following the incorporation of 14C-formate into soluble Nucleotides, uric acid and RNA riboNucleotides. After castration, GMP formation was less than that of AMP, and Purine Nucleotide catabolism and RNA synthesis decreased. Testosterone administration did not modify GMP or AMP synthesis, but restored Purine Nucleotide catabolism and RNA production to normal values. These results demonstrate the influence of testosterone on Purine Nucleotide metabolism in a non-reproductive organ.
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Purine Nucleotide metabolism in lymphocytes of B-cell chronic lymphocytic leukemia patients
Biomedicine & Pharmacotherapy, 1995Co-Authors: Antonella Tabucchi, Daniela Vannoni, E. Dispensa, Filippo Carlucci, Roberto Leoncini, E. Consolmagno, Maria Pizzichini, Enrico Marinello, Roberto PaganiAbstract:Summary Purine Nucleotides were studied in human peripheral blood lymphocytes from normal subjects and patients with chronic B-cell lymphocytic leukemia (B-CLL). Nucleotide content was determined by high performance liquid chromatography (HPLC). The overall rate of Purine Nucleotide synthesis was measured following the incorporation of l4 C-formate into the Nucleotides of a lymphocytic suspension. Results indicate a substantially reduced rate of Purine Nucleotide metabolism.
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Purine Nucleotide content of lymphocytes from healthy subjects and asymptomatic HIV-1 seropositive patients.
Recenti progressi in medicina, 1991Co-Authors: Antonella Tabucchi, Filippo Carlucci, Enrico Marinello, Maria Carla Re, L. Bisozzi, Cacopardo F, Roberto PaganiAbstract:: The Purine Nucleotide content of lymphocytes of normal subjects and asymptomatic HIV-1 seropositive patients was analyzed by HPLC. An increase in IMP and a decrease in ADP, GDP, ATP and GPT were observed in the HIV-infected patients with respect to healthy subjects. The changes may depend on different factors and indicate that the virus influences Purine Nucleotide metabolism of the cell. The finding sheds light on the metabolic situation of the infected cell, and could be applied to monitoring the disease.
Roberto Leoncini - One of the best experts on this subject based on the ideXlab platform.
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Effect of testosterone on Purine Nucleotide metabolism in rat liver.
Hormone and Metabolic Research, 2004Co-Authors: Enrico Marinello, Daniela Vannoni, Brunetta Porcelli, Lucia Terzuoli, Roberto Leoncini, Resconi GAbstract:: In previous studies, we found that castration induced interesting morphological and biochemical changes in rat liver. For the present study, we have examined the effects of testosterone on the kinetics of Purine Nucleotide metabolism with the aim of determining the steps affected by testosterone deficiency. A biomathematical model of Purine Nucleotide metabolism was used to analyze the many reactions involved. The model simplifies Purine Nucleotide metabolism to four main steps: 1) de novo synthesis from PRPP to IMP; 2) the inosinic branch point from IMP to GMP or AMP; 3) catabolism of IMP, AMP and GMP to uric acid; 4) RNA and DNA formation from AMP and GMP. We evaluated rate constants from each step from variations in specific radioactivity of metabolites labelled with (14)C-formate, a precursor of de novo synthesis. The model was applied to the liver of normal and castrated rats before and after testosterone treatment. All four steps were slowed after castration, and were not completely restored by androgen administration. The model can give a clear representation of the kinetics of the reactions involved in the liver Nucleotide metabolism investigated here, and we propose that a similar approach could be useful whenever a quantitative evaluation of the results obtained in vivo after administration of labelled precursors is required.
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The influence of testosterone on Purine Nucleotide metabolism in rat liver.
Life Sciences, 1995Co-Authors: Maria Pizzichini, Daniela Vannoni, Roberto Leoncini, Enrico Marinello, Roberto PaganiAbstract:Abstract Purine Nucleotide metabolism was studied in rat liver by following the incorporation of 14C-formate into soluble Nucleotides, uric acid and RNA riboNucleotides. After castration, GMP formation was less than that of AMP, and Purine Nucleotide catabolism and RNA synthesis decreased. Testosterone administration did not modify GMP or AMP synthesis, but restored Purine Nucleotide catabolism and RNA production to normal values. These results demonstrate the influence of testosterone on Purine Nucleotide metabolism in a non-reproductive organ.
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Purine Nucleotide metabolism in lymphocytes of B-cell chronic lymphocytic leukemia patients
Biomedicine & Pharmacotherapy, 1995Co-Authors: Antonella Tabucchi, Daniela Vannoni, E. Dispensa, Filippo Carlucci, Roberto Leoncini, E. Consolmagno, Maria Pizzichini, Enrico Marinello, Roberto PaganiAbstract:Summary Purine Nucleotides were studied in human peripheral blood lymphocytes from normal subjects and patients with chronic B-cell lymphocytic leukemia (B-CLL). Nucleotide content was determined by high performance liquid chromatography (HPLC). The overall rate of Purine Nucleotide synthesis was measured following the incorporation of l4 C-formate into the Nucleotides of a lymphocytic suspension. Results indicate a substantially reduced rate of Purine Nucleotide metabolism.
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Some Aspects of Purine Nucleotide Metabolism in Human Lymphocytes before and after Infection with HIV-1 Virus: Nucleotide Content
Advances in Experimental Medicine and Biology, 1991Co-Authors: Roberto Pagani, Antonella Tabucchi, Filippo Carlucci, Roberto Leoncini, E. Consolmagno, M. Molinelli, P. ValerioAbstract:The evaluation of intracellular metabolism of Purine Nucleotides is important in many conditions, during, for example, proliferation, or maturation of the cell -i.e. leukemia and SCID (= severe congenital immunodeficiency)- and can be studied following different procedures: 1) evaluation of Purine Nucleotide content (1); 2) incorporation of labelled precursors of the Purines, e.g. 14C-glycine or 14C-formate with kinetics based on biomathematical models (2); 3) assay of each individual enzymatic activity, involved in the various pathways of Purine Nucleotide metabolism, the de novo synthesis, the salvage pathway, and the Purine Nucleotide catabolism (2).
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Some aspects of Purine Nucleotide metabolism in lymphocytes of B-CLL.
Tumori, 1991Co-Authors: Antonella Tabucchi, Daniela Vannoni, Brunetta Porcelli, Lucia Terzuoli, Roberto Pagani, Roberto Leoncini, Maria Pizzichini, Enrico Marinello, E. DispensaAbstract:: The authors studied the behavior of some enzymes involved in Purine Nucleotide metabolism in human peripheral blood lymphocytes from normal and B-cell chronic lymphocytic leukemia subjects. Determinations were made with radiochemical methods associated with high performance liquid chromatography. Results indicated a marked increase in de novo Purine synthesis enzymes, particularly those of the "inosinic branch point". The latter were absent in normal lymphocytes, whereas they were well evident in leukemic lymphocytes, with the exception of AMP-S synthetase. Whereas the enzymes of the "salvage pathway" were spared in comparison to other proteins, those of the "catabolic pathway" significantly decreased. The authors discuss the possibility that such enzymes may be used as tumor markers.
Mikhail Chernov - One of the best experts on this subject based on the ideXlab platform.
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Arginylation regulates Purine Nucleotide biosynthesis by enhancing the activity of phosphoribosyl pyrophosphate synthase
Nature Communications, 2015Co-Authors: Fangliang Zhang, Devang M. Patel, Kristen Colavita, Irina A. Rodionova, Brian Buckley, David A. Scott, Akhilesh Kumar, Svetlana A. Shabalina, Sougata Saha, Mikhail ChernovAbstract:The phosphoribosyl pyrophosphate synthase PRPS2 catalyses the first step of de novo Purine Nucleotide biosynthesis, and has recently been shown to couple protein and Nucleotide metabolism. Zhang et al. demonstrate that PRPS2 activity is regulated by tRNA-dependent post-translational addition of arginine.
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arginylation regulates Purine Nucleotide biosynthesis by enhancing the activity of phosphoribosyl pyrophosphate synthase
Nature Communications, 2015Co-Authors: Fangliang Zhang, Devang M. Patel, Kristen Colavita, Irina A. Rodionova, Brian Buckley, David A. Scott, Akhilesh Kumar, Svetlana A. Shabalina, Sougata Saha, Mikhail ChernovAbstract:Protein arginylation is an emerging post-translational modification that targets a number of metabolic enzymes; however, the mechanisms and downstream effects of this modification are unknown. Here we show that lack of arginylation renders cells vulnerable to Purine Nucleotide synthesis inhibitors and affects the related glycine and serine biosynthesis pathways. We show that the Purine Nucleotide biosynthesis enzyme PRPS2 is selectively arginylated, unlike its close homologue PRPS1, and that arginylation of PRPS2 directly facilitates its biological activity. Moreover, selective arginylation of PRPS2 but not PRPS1 is regulated through a coding sequence-dependent mechanism that combines elements of mRNA secondary structure with lysine residues encoded near the N-terminus of PRPS1. This mechanism promotes arginylation-specific degradation of PRPS1 and selective retention of arginylated PRPS2 in vivo. We therefore demonstrate that arginylation affects both the activity and stability of a major metabolic enzyme.
Maria Pizzichini - One of the best experts on this subject based on the ideXlab platform.
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Purine Nucleotide metabolism: specific aspects in chronic lymphocytic leukemia lymphocytes
Biochimica et Biophysica Acta, 1997Co-Authors: Filippo Carlucci, C Di Pietro, Francesca Rosi, Maria Pizzichini, Enrico Marinello, Antonella TabucchiAbstract:Abstract The metabolism of Purine Nucleotides was studied in human peripheral blood lymphocytes from healthy subjects and patients with B-cell chronic lymphocytic leukemia. Nucleotide content was determined by HPLC. The rate of de novo synthesis of Purine Nucleotides was measured kinetically by following the incorporation of 14 C-formate into the Nucleotides of a lymphocyte suspension. The patterns of the main enzymes involved in Purine Nucleotide metabolism (those of the salvage pathway and catabolism) were estimated by a radiochemical method. Although the data expressed in relation to cells and protein showed some discrepancies, several common differences were evident in both cases. The main differences were an increase in NAD and IMP, a sharp decrease in 5′-nucleotidase activities and in total guanylate content and synthesis, and an increase in the A/G ratio in lymphocytes of patients with respect to controls. The changes in these parameters in CLL indicate an imbalance in Purine metabolism and may play a specific role in the biology of the leukemia cell. They are also potential biochemical markers of lymphoid malignancies and may be useful in chemotherapic applications. ©1997 Elsevier Science B.V. All rights reserved.
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The influence of testosterone on Purine Nucleotide metabolism in rat liver.
Life Sciences, 1995Co-Authors: Maria Pizzichini, Daniela Vannoni, Roberto Leoncini, Enrico Marinello, Roberto PaganiAbstract:Abstract Purine Nucleotide metabolism was studied in rat liver by following the incorporation of 14C-formate into soluble Nucleotides, uric acid and RNA riboNucleotides. After castration, GMP formation was less than that of AMP, and Purine Nucleotide catabolism and RNA synthesis decreased. Testosterone administration did not modify GMP or AMP synthesis, but restored Purine Nucleotide catabolism and RNA production to normal values. These results demonstrate the influence of testosterone on Purine Nucleotide metabolism in a non-reproductive organ.
-
Purine Nucleotide metabolism in lymphocytes of B-cell chronic lymphocytic leukemia patients
Biomedicine & Pharmacotherapy, 1995Co-Authors: Antonella Tabucchi, Daniela Vannoni, E. Dispensa, Filippo Carlucci, Roberto Leoncini, E. Consolmagno, Maria Pizzichini, Enrico Marinello, Roberto PaganiAbstract:Summary Purine Nucleotides were studied in human peripheral blood lymphocytes from normal subjects and patients with chronic B-cell lymphocytic leukemia (B-CLL). Nucleotide content was determined by high performance liquid chromatography (HPLC). The overall rate of Purine Nucleotide synthesis was measured following the incorporation of l4 C-formate into the Nucleotides of a lymphocytic suspension. Results indicate a substantially reduced rate of Purine Nucleotide metabolism.
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Some aspects of Purine Nucleotide metabolism in lymphocytes of B-CLL.
Tumori, 1991Co-Authors: Antonella Tabucchi, Daniela Vannoni, Brunetta Porcelli, Lucia Terzuoli, Roberto Pagani, Roberto Leoncini, Maria Pizzichini, Enrico Marinello, E. DispensaAbstract:: The authors studied the behavior of some enzymes involved in Purine Nucleotide metabolism in human peripheral blood lymphocytes from normal and B-cell chronic lymphocytic leukemia subjects. Determinations were made with radiochemical methods associated with high performance liquid chromatography. Results indicated a marked increase in de novo Purine synthesis enzymes, particularly those of the "inosinic branch point". The latter were absent in normal lymphocytes, whereas they were well evident in leukemic lymphocytes, with the exception of AMP-S synthetase. Whereas the enzymes of the "salvage pathway" were spared in comparison to other proteins, those of the "catabolic pathway" significantly decreased. The authors discuss the possibility that such enzymes may be used as tumor markers.
