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Journal of Virology Nov 2015Macrophages are a target for infection with HIV and represent one of the viral reservoirs that are relatively resistant to current antiretroviral drugs. Here we...
UNLABELLED
Macrophages are a target for infection with HIV and represent one of the viral reservoirs that are relatively resistant to current antiretroviral drugs. Here we demonstrate that methylglyoxal-bis-guanylhydrazone (MGBG), a polyamine analog and potent S-adenosylmethionine decarboxylase inhibitor, decreases HIV expression in monocytes and macrophages. MGBG is selectively concentrated by these cells through a mechanism consistent with active transport by the polyamine transporter. Using a macrophage-tropic reporter virus tagged with the enhanced green fluorescent protein, we demonstrate that MGBG decreases the frequency of HIV-infected cells. The effect is dose dependent and correlates with the production of HIV p24 in culture supernatants. This anti-HIV effect was further confirmed using three macrophage-tropic primary HIV isolates. Viral life cycle mapping studies show that MGBG inhibits HIV DNA integration into the cellular DNA in both monocytes and macrophages.
IMPORTANCE
Our work demonstrates for the first time the selective concentration of MGBG by monocytes/macrophages, leading to the inhibition of HIV-1 expression and a reduction in proviral load within macrophage cultures. These results suggest that MGBG may be useful in adjunctive macrophage-targeted therapy for HIV infection.
Topics: Adenosylmethionine Decarboxylase; Anti-Retroviral Agents; Biological Transport, Active; CD4 Antigens; Cells, Cultured; Green Fluorescent Proteins; HIV Core Protein p24; HIV Infections; HIV-1; Humans; Lipopolysaccharide Receptors; Macrophages; Mitoguazone; Monocytes; Receptors, CCR5; Virus Integration; Virus Replication
PubMed: 26223636
DOI: 10.1128/JVI.01692-15 -
Methods in Molecular Biology (Clifton,... 2022We present here detailed protocols for the newly developed multiplex glycan bead array (MGBA) for the high throughput and high content analyses of various glycan-binding...
We present here detailed protocols for the newly developed multiplex glycan bead array (MGBA) for the high throughput and high content analyses of various glycan-binding proteins including anti-glycan antibodies. This platform takes advantage of the commercially available Luminex beads to construct glycan arrays that are easily customizable at will and anytime by researchers. The platform allows the simultaneous analyses of up to 500 glycans and 384 samples at a time. By using multiple arrays, a researcher can analyze thousands of glycans and tens of thousands of samples within a short period. The assay is highly sensitive, specific, reproducible, economic, and fast. Furthermore, the bead array platform is approved for use in clinical settings, speeding up the translation of laboratory discoveries into patient care.
Topics: Antibodies; Carrier Proteins; Humans; Mitoguazone; Polysaccharides; Proteins
PubMed: 34972929
DOI: 10.1007/978-1-0716-2148-6_3 -
The Biochemical Journal Jun 1988The aim of the present study was to evaluate the role of polyamines in the metabolism and insulin production of pancreatic-islet cells. For this purpose islets were...
The aim of the present study was to evaluate the role of polyamines in the metabolism and insulin production of pancreatic-islet cells. For this purpose islets were prepared from adult mice and used either immediately or after tissue culture. There was a significant decrease in the islet content of spermidine during culture, although the effect was less pronounced in a high glucose concentration. Furthermore, a stimulatory effect of a high glucose concentration, as compared with low guclose, on the content of spermine was observed. To elucidate further the role of polyamaines in beta-cell physiology, the ornithine decarboxylase inhibitors difuoromethylornithine (DFMO) and methylacetylenic putrescine (MAP) and the S-adenosylmethionine decarboxylase inhibitor ethylglyoxal bis(guanylhydrazone) (EGBG) were added to the culture media. Addition of DFMO together with MAP decreased the cellular contents of putrescine and spermidine, whereas the content of sperimine was unaffected. When EGBG was added in combination with DFMO and MAP, there was a decrease in the content of spermine also. Cell viability in the islets depleted of their polyamine contents was not impaired, as assessed by determinations of oxygen-uptake rates and ATP contents. Depletion of putescine plus spermidine by addition of DFMO+MAP was associated with decreased biosynthesis of (pro)insulin and total protein. When the content of spermine was decreased also by the further addition of EGBG, the decrease in (pro) insulin biosynthesis was more pronounced and was paralleled by a decrease in the insulin-mRNA content. Under these conditions, the glucose-stimulated insulin release, the insulin content and the rates of islet DNA synthesis were also decreased. It is concluded that putrescine and spermidine are necessary for the maintenance of normal insulin and protein biosynthesis, whereas spermine may exert a role in some other cellular processes, such as DNA replication, RNA transcription and glucose-stimulated insulin release.
Topics: Adenosine Triphosphate; Alkynes; Animals; Cells, Cultured; DNA; Diamines; Eflornithine; Glucose; Insulin; Islets of Langerhans; Male; Mice; Mitoguazone; Oxygen Consumption; Polyamines; Protein Biosynthesis; Putrescine; RNA, Messenger
PubMed: 3138973
DOI: 10.1042/bj2520701 -
The Biochemical Journal Oct 1990The aim of the present study was to evaluate the possible role for polyamines in the glucose regulation of the metabolism of insulin mRNA of pancreatic islet cells. For...
The aim of the present study was to evaluate the possible role for polyamines in the glucose regulation of the metabolism of insulin mRNA of pancreatic islet cells. For this purpose islets were prepared from adult mice and cultured for 2 days in culture medium RPMI 1640 containing 3.3 mM- or 16.7 mM-glucose with or without the addition of the inhibitors of polyamine biosynthesis difluoromethylornithine (DFMO) and ethylglyoxal bis(guanylhydrazone) (EGBG). Culture at the high glucose concentration increased the islet contents of both insulin mRNA and polyamines. The synthesis of total RNA, total islet polyamines and polyamines associated with islet nuclei was also increased. When the combination of DFMO and EGBG was added in the presence of 16.7 mM-glucose, low contents of insulin mRNA, spermine and spermidine were observed. Total islet polyamine synthesis was also depressed by DFMO + EGBG, unlike islet biosynthesis of polyamines associated with nuclei, which was not equally decreased by the polyamine-synthesis inhibitors. Total RNA synthesis and turnover was not affected by DFMO + EGBG. Finally, actinomycin D attenuated the glucose-induced enhancement of insulin mRNA, and cycloheximide counteracted the insulin-mRNA attenuation induced by inhibition of polyamine synthesis. It is concluded that the glucose-induced increase in insulin mRNA is paralleled by increased contents and rates of polyamine biosynthesis and that an attenuation of the increase in polyamines prevents the increase in insulin mRNA. In addition, the results are compatible with the view that polyamines exert their effects on insulin mRNA mainly by increasing the stability of this messenger.
Topics: Animals; Cell Nucleus; Culture Techniques; Cycloheximide; Dactinomycin; Eflornithine; Gene Expression; Glucose; Insulin; Islets of Langerhans; Male; Mice; Mitoguazone; Polyamines; RNA, Messenger; Spermidine; Spermine
PubMed: 2241922
DOI: 10.1042/bj2710393 -
The Biochemical Journal Apr 1984Mammalian fibroblasts were cultured in the presence of alpha-methylornithine and/or methylglyoxal bis(guanylhydrazone), which inhibit the synthesis of polyamines. This...
Mammalian fibroblasts were cultured in the presence of alpha-methylornithine and/or methylglyoxal bis(guanylhydrazone), which inhibit the synthesis of polyamines. This led to a decrease in the cellular content of the polyamines spermine and spermidine by up to 60% when the cells were grown in the presence of both drugs together. The activity of the chromatin-associated enzyme ADP-ribosyltransferase was enhanced 2-3-fold in the drug-treated cells when measured in cells subsequently rendered permeable to exogenous NAD+, the substrate for the transferase. This is a novel and surprising observation, since the transferase is invariably activated by the addition of polyamines to a suitable incubation system such as permeabilized cells, isolated nuclei or the purified enzyme. We found no evidence that the activation was due to the appearance of DNA strand breaks, by using a variety of procedures including both neutral [the 'nucleoid' technique of Cook & Brazell [(1975) J. Cell Sci. 19, 261-279; (1976) J. Cell Sci. 22, 287-302]] and alkaline sucrose-gradient centrifugation and gel electrophoresis, suggesting that this therefore may not be the only means of regulating the activity of ADP-ribosyltransferase and that polyamines may have a role to play in this regard in vivo.
Topics: Adenosine Diphosphate Ribose; Animals; Cells, Cultured; Centrifugation, Density Gradient; Chromatography; Cricetinae; DNA; Enzyme Activation; Fibroblasts; Kidney; Mitoguazone; Nucleotidyltransferases; Ornithine; Poly(ADP-ribose) Polymerases; Spermidine; Spermine
PubMed: 6326755
DOI: 10.1042/bj2190211 -
Antimicrobial Agents and Chemotherapy Jun 1996A series of novel aromatic derivatives based on the structure of methylglyoxal bis(guanylhydrazone) (MGBG) was examined for in vitro antitrypanosomal activities and...
A series of novel aromatic derivatives based on the structure of methylglyoxal bis(guanylhydrazone) (MGBG) was examined for in vitro antitrypanosomal activities and cytotoxicities for human cells. One-third of the compounds tested showed trypanocidal activity at concentrations below 0.5 microM after an incubation period of 72 h. Structure-activity analysis revealed that bicyclic compounds with homocyclic rings and unmodified termini were the most active compounds. Results obtained in three laboratories employing different methods and trypanosome populations consistently ranked compound CGP 40215A highest. This compound had a 50% inhibitory concentration of 0.0045 microM for Trypanosoma brucei rhodesiense, was also active against other trypanosome species, including a multidrug-resistant Trypanosoma brucei brucei, and was significantly less toxic than other compounds tested for a human adenocarcinoma cell line, with a 50% inhibitory concentration of 1.14 mM. The effect of CGP 40215A was time and dose dependent, and low concentrations of the compound required exposure times of > 2 days to exert trypanocidal activity. Compounds were inactive against Leishmania donovani and Trypanosoma cruzi amastigotes in murine macrophages in vitro.
Topics: Adenocarcinoma; Adenosylmethionine Decarboxylase; Animals; Humans; Mitoguazone; Structure-Activity Relationship; Time Factors; Trypanocidal Agents; Trypanosoma; Tumor Cells, Cultured
PubMed: 8726017
DOI: 10.1128/AAC.40.6.1442 -
Annals of Oncology : Official Journal... Jun 2010High-dose chemotherapy (HDT) followed by autologous stem-cell transplantation (ASCT) is considered the gold standard in the treatment of patients with relapsed or...
BACKGROUND
High-dose chemotherapy (HDT) followed by autologous stem-cell transplantation (ASCT) is considered the gold standard in the treatment of patients with relapsed or refractory Hodgkin's lymphoma (HL). However, the optimal salvage regimen has not yet been established.
PATIENTS AND METHODS
We retrospectively analyzed the efficacy and toxicity of MINE (mesna, ifosfamide, mitoxantrone, and etoposide) alternated with ESHAP (etoposide, methylprednisolone, high-dose cytarabine, and cisplatin) in the treatment of 61 relapsed or refractory HL patients after ABVD-based chemotherapy.
RESULTS
Overall, 25 patients (41%) achieved a complete response (CR), 23 (38%) a partial response (PR), 4 (7%) a stable disease, and 8 (13%) progressed for an overall response rate of 79%. Response to first-line chemotherapy was the most important prognostic factor for response to MINE-ESHAP (P = 0.041). No grade 4 extrahematologic toxic effects or toxic deaths were observed. Adequate peripheral blood stem-cell collection was achieved in 56 of 59 (95%) mobilized patients. Overall survival and event-free survival after HDT and ASCT were significantly higher for patients achieving CR/PR in comparison with those refractory to MINE-ESHAP (46% and 35% versus 74% and 69%, respectively).
CONCLUSION
MINE-ESHAP results in a high response rate with acceptable toxicity in patients with HL having failed ABVD-based treatment.
Topics: Adolescent; Adult; Antineoplastic Combined Chemotherapy Protocols; Cisplatin; Combined Modality Therapy; Cytarabine; Drug Administration Schedule; Etoposide; Female; Hodgkin Disease; Humans; Ifosfamide; Male; Middle Aged; Mitoguazone; Periodicity; Prednisone; Recurrence; Retrospective Studies; Salvage Therapy; Stem Cell Transplantation; Transplantation, Autologous; Treatment Failure; Vinblastine; Young Adult
PubMed: 19889622
DOI: 10.1093/annonc/mdp487 -
PloS One 2016This study determined if the variation in grain filling parameters between two different spikelet types of rice (Oryza sativa L.) is regulated by the hormonal levels in...
This study determined if the variation in grain filling parameters between two different spikelet types of rice (Oryza sativa L.) is regulated by the hormonal levels in the grains. Two rice mutants, namely, a large-grain mutant (AZU-M) and a small-grain mutant (ZF802-M), and their respective wild types (AZU-WT and ZF802-WT) were grown in the field. The endosperm cell division rate, filling rate, and hormonal levels: zeatin + zeatin riboside (Z+ZR), indo-3-acetic acid (IAA), polyamines (PAs), and abscisic acid (ABA) were determined. The results showed that there was no significant difference between the filling and endosperm cell division rates. These rates were synchronous between the superior and inferior spikelets for both mutants. However, the abovementioned parameters were significantly different between the two spikelet types for the two wild types. The superior spikelets filled faster and their filling rate was higher compared to the inferior ones. Changes in the concentrations of plant hormones were consistent with the observed endosperm cell division rate and the filling rate for both types of spikelets of mutant and wild type plants. Regression analysis showed a significant positive correlation between cell division and filling rates with the concentrations of the investigated hormones. Exogenous chemical application verified the role of ABA, IAA, and PAs in grain filling. The results indicate that poor filling of inferior spikelets in rice occurs primarily due to the reduced hormone concentrations therein, leading to lower division rate of endosperm cells, fewer endosperm cells, slower filling rate, and smaller grain weight.
Topics: Abscisic Acid; Edible Grain; Endosperm; Enzyme-Linked Immunosorbent Assay; Mitoguazone; Oryza; Plant Growth Regulators; Plants, Genetically Modified; Polyamines; Putrescine; Spermidine; Zeatin
PubMed: 27780273
DOI: 10.1371/journal.pone.0165321 -
Microbiology (Reading, England) Mar 1996Since polyamines (PAs) play a potential role in the regulation of growth and developmental processes in a wide variety of organisms, we have examined the influence of...
Since polyamines (PAs) play a potential role in the regulation of growth and developmental processes in a wide variety of organisms, we have examined the influence of the PAs putrescine (Put) and spermidine (Spd) and the PA biosynthetic inhibitors alpha-difluoromethylornithine (DFMO), alpha-difluoromethylarginine (DFMA), methylglyoxal bis-(guanylhydrazone) (MGBG) and cyclohexylamine (CHA), singly and in combinations on microcycle conidiation (MC) in Aspergillus flavus. The exogenous application of the diamine Put (concentrations ranging from 0.1 to 5 mM) caused a sharp decline of MC in a dose-dependent fashion, but induced vegetative growth. However, the triamine Spd (0.1-5 mM) had a minimal effect on MC and induced a shift from MC to normal condition. PA inhibitors, especially DFMO, MGBG and CHA, produced greater inhibition of MC and complete inhibition of MC was observed at 5 mM of these inhibitors. DFMA even at 5 mM had only a weak inhibitory effect on MC. DFMO also inhibited conidial germination and germ tube growth. MGBG and CHA, while having an inhibitory effect on MC, induced vegetative growth. The inhibitory effect of PA inhibitors was partially reversed by exogenous Put or Spd, with Spd being more effective than Put. The analysis of free PA levels during various phases of MC revealed that undifferentiated spores contained a high Put/Spd ratio and there was a dramatic decrease in Put/Spd ratio before and during microcycle conidiophore maturity. The change in spermine titres could not be detected. These observations imply that Put is essential for vegetative growth, while Spd is involved in MC, and that a low Put/Spd ratio seems to be important for spore differentiation to MC.
Topics: Aspergillus flavus; Cell Division; Cyclohexylamines; Eflornithine; Enzyme Inhibitors; Mitoguazone; Putrescine; Spermidine
PubMed: 8868426
DOI: 10.1099/13500872-142-3-517 -
Journal of Applied Microbiology 2004Effect of polyamines and their biosynthesis inhibitors on the production of hyperthermostable and Ca2+ -independent alpha-amylase by Geobacillus thermoleovorans MTCC...
Amelioration in secretion of hyperthermostable and Ca2+ -independent alpha-amylase of Geobacillus thermoleovorans by some polyamines and their biosynthesis inhibitor methylglyoxal-bis-guanylhydrazone.
AIM
Effect of polyamines and their biosynthesis inhibitors on the production of hyperthermostable and Ca2+ -independent alpha-amylase by Geobacillus thermoleovorans MTCC 4220.
METHODS AND RESULTS
The alpha-amylase was produced in starch-yeast extract-tryptone (SYT) broth with different polyamines (PA) and polyamine biosynthesis inhibitors, methylglyoxal-bis-guanylhydrazone (MGBG) and cyclohexylammonium sulphate (CHA) at 70 degrees C. The bacterial pellets were obtained after growing G. thermoleovorans at different temperatures, and used in determining total PA. The cell-free culture filtrates were used in alpha-amylase assays. During growth, total polyamines in biomass increased till 2 h, and thereafter, decreased gradually. The total polyamine content was very high in the biomass cultivated at 55 degrees C when compared with that of higher temperatures. Enzyme titre enhanced up to 70 degrees C, and thereafter declined. Extracellular enzyme and protein levels declined in the presence of exogenously added PA. The intracellular enzyme titres, however, were higher in putrescine (put) and spermidine (spd) than in spermine (spm). Polyamine biosynthesis inhibitor, MGBG enhanced secretion of alpha-amylase in a laboratory fermentor as well as shake flasks, although CHA did not affect it.
CONCLUSIONS
The intracellular accumulation of put in the presence of MGBG appeared to enhance synthesis and secretion of alpha-amylase. Extracellular enzyme and protein levels were low in the presence of exogenously added PA, but their intracellular levels, however, were higher in put and spd than in spm.
SIGNIFICANCE AND IMPACT OF THE STUDY
A substantial increase in the synthesis and secretion of alpha-amylase was attained in G. thermoleovorans in the presence of polyamine biosynthesis inhibitor MGBG.
Topics: Bacillus; Calcium; Dose-Response Relationship, Drug; Enzyme Inhibitors; Enzyme Stability; Hot Springs; Hot Temperature; Mitoguazone; Polyamines; Temperature; Water Microbiology; alpha-Amylases
PubMed: 15479417
DOI: 10.1111/j.1365-2672.2004.02395.x