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Tropical Medicine and Infectious Disease Jun 2024L-arginine metabolism is strongly linked with immunity to mycobacteria, primarily through the antimicrobial activity of nitric oxide (NO). The potential to modulate...
Therapeutic Modulation of Arginase with nor-NOHA Alters Immune Responses in Experimental Mouse Models of Pulmonary Tuberculosis including in the Setting of Human Immunodeficiency Virus (HIV) Co-Infection.
L-arginine metabolism is strongly linked with immunity to mycobacteria, primarily through the antimicrobial activity of nitric oxide (NO). The potential to modulate tuberculosis (TB) outcomes through interventions that target L-arginine pathways are limited by an incomplete understanding of mechanisms and inadequate in vivo modeling. These gaps in knowledge are compounded for HIV and Mtb co-infections, where activation of arginase-1 due to HIV infection may promote survival and replication of both Mtb and HIV. We utilized in vitro and in vivo systems to determine how arginase inhibition using N-hydroxy-nor-L-arginine (nor-NOHA) alters L-arginine pathway metabolism relative to immune responses and disease outcomes following Mtb infection. Treatment with nor-NOHA polarized murine macrophages (RAW 264.7) towards M1 phenotype, increased NO, and reduced Mtb in RAW macrophages. In Balb/c mice, nor-NOHA reduced pulmonary arginase and increased the antimicrobial metabolite spermine in association with a trend towards reduced Mtb CFU in lung. In humanized immune system (HIS) mice, HIV infection increased plasma arginase and heightened the pulmonary arginase response to Mtb. Treatment with nor-NOHA increased cytokine responses to Mtb and Mtb/HIV in lung tissue but did not significantly alter bacterial burden or viral load. Our results suggest that L-arginine pathway modulators may have potential as host-directed therapies to augment antibiotics in TB chemotherapy.
PubMed: 38922041
DOI: 10.3390/tropicalmed9060129 -
Cells Jun 2024Hepatitis C virus (HCV) is an oncogenic virus that causes chronic liver disease in more than 80% of patients. During the last decade, efficient direct-acting antivirals...
Hepatitis C virus (HCV) is an oncogenic virus that causes chronic liver disease in more than 80% of patients. During the last decade, efficient direct-acting antivirals were introduced into clinical practice. However, clearance of the virus does not reduce the risk of end-stage liver diseases to the level observed in patients who have never been infected. So, investigation of HCV pathogenesis is still warranted. Virus-induced changes in cell metabolism contribute to the development of HCV-associated liver pathologies. Here, we studied the impact of the virus on the metabolism of polyamines and proline as well as on the urea cycle, which plays a crucial role in liver function. It was found that HCV strongly suppresses the expression of arginase, a key enzyme of the urea cycle, leading to the accumulation of arginine, and up-regulates proline oxidase with a concomitant decrease in proline concentrations. The addition of exogenous proline moderately suppressed viral replication. HCV up-regulated transcription but suppressed protein levels of polyamine-metabolizing enzymes. This resulted in a decrease in polyamine content in infected cells. Finally, compounds targeting polyamine metabolism demonstrated pronounced antiviral activity, pointing to spermine and spermidine as compounds affecting HCV replication. These data expand our understanding of HCV's imprint on cell metabolism.
Topics: Proline; Humans; Hepacivirus; Polyamines; Urea; Virus Replication; Arginase; Antiviral Agents; Hepatitis C; Cell Line, Tumor; Proline Oxidase
PubMed: 38920664
DOI: 10.3390/cells13121036 -
Cell & Bioscience Jun 2024Polyamines (PA) are polycations with pleiotropic functions in cellular physiology and pathology. In particular, PA have been involved in the regulation of cell... (Review)
Review
Polyamines (PA) are polycations with pleiotropic functions in cellular physiology and pathology. In particular, PA have been involved in the regulation of cell homeostasis and proliferation participating in the control of fundamental processes like DNA transcription, RNA translation, protein hypusination, autophagy and modulation of ion channels. Indeed, their dysregulation has been associated to inflammation, oxidative stress, neurodegeneration and cancer progression. Accordingly, PA intracellular levels, derived from the balance between uptake, biosynthesis, and catabolism, need to be tightly regulated. Among the mechanisms that fine-tune PA metabolic enzymes, emerging findings highlight the importance of noncoding RNAs (ncRNAs). Among the ncRNAs, microRNA, long noncoding RNA and circRNA are the most studied as regulators of gene expression and mRNA metabolism and their alteration have been frequently reported in pathological conditions, such as cancer progression and brain diseases. In this review, we will discuss the role of ncRNAs in the regulation of PA genes, with a particular emphasis on the changes of this modulation observed in health disorders.
PubMed: 38918813
DOI: 10.1186/s13578-024-01235-3 -
ELife Jun 2024The emergence of new protein functions is crucial for the evolution of organisms. This process has been extensively researched for soluble enzymes, but it is largely...
The emergence of new protein functions is crucial for the evolution of organisms. This process has been extensively researched for soluble enzymes, but it is largely unexplored for membrane transporters, even though the ability to acquire new nutrients from a changing environment requires evolvability of transport functions. Here, we demonstrate the importance of environmental pressure in obtaining a new activity or altering a promiscuous activity in members of the amino acid-polyamine-organocation (APC)-type yeast amino acid transporters family. We identify APC members that have broader substrate spectra than previously described. Using in vivo experimental evolution, we evolve two of these transporter genes, and , toward new substrate specificities. Single mutations on these transporters are found to be sufficient for expanding the substrate range of the proteins, while retaining the capacity to transport all original substrates. Nonetheless, each adaptive mutation comes with a distinct effect on the fitness for each of the original substrates, illustrating a trade-off between the ancestral and evolved functions. Collectively, our findings reveal how substrate-adaptive mutations in membrane transporters contribute to fitness and provide insights into how organisms can use transporter evolution to explore new ecological niches.
Topics: Mutation; Saccharomyces cerevisiae; Amino Acid Transport Systems; Substrate Specificity; Evolution, Molecular; Polyamines; Saccharomyces cerevisiae Proteins; Genetic Fitness; Amino Acids
PubMed: 38916596
DOI: 10.7554/eLife.93971 -
Gene Jun 2024Products from stingless bees are rich reservoirs of microbial diversity, including yeasts with fermentative potential. Previously, two Saccharomyces cerevisiae strains,...
Products from stingless bees are rich reservoirs of microbial diversity, including yeasts with fermentative potential. Previously, two Saccharomyces cerevisiae strains, JP14 and IP9, were isolated from Jataí (Tetragonisca angustula) and Iraí (Nannotrigona testaceicornis) bees, respectively, aiming at mead production. Both strains presented great osmotic and sulfite tolerance, and ethanol production, although they have a high free amino nitrogen demand. Herein, their genomes were sequenced, assembled, and annotated, and the variants were compared to the S. cerevisiae S288c reference strain. The final assembly of IP9 and JP14 presented high N50 and BUSCO scores, and more than 6430 protein-coding genes. Additionally, nQuire predicted the ploidy of IP9 as diploid, but the results were not enough to determine the ploidy of JP14. The mitochondrial genomes of IP9 and JP14 presented the same gene content as S288c but the genes were rearranged and fragmented in different patterns. Meanwhile, the genes with mutations of high impact (e.g., indels, gain of stop codon) for both yeasts were enriched for transmembrane transport, electron transfer, oxidoreductase, heme binding, fructose, mannose, and glucose transport, activities related to the respiratory chain and sugar metabolism. The IP9 strain presented copy number gains in genes related to sugar transport and cell morphogenesis; in JP14, genes were enriched for disaccharide metabolism and transport, response to reactive oxygen species, and polyamine transport. On the other hand, IP9 presented copy number losses related to disaccharide, thiamine, and aldehyde metabolism, while JP14 presented depletions related to disaccharide, oligosaccharide, asparagine, and aspartate metabolism. Notably, both strains presented a killer toxin gene, annotated from the assembling of unmapped reads, representing a potential mechanism for the control of other microorganisms population in the environment. Therefore, the annotated genomes of JP14 and IP9 presented a high selective pressure for sugar and nitrogen metabolism and stress response, consistent with their isolation source and fermentative properties.
PubMed: 38914244
DOI: 10.1016/j.gene.2024.148722 -
International Journal of Medical... 2024Inflammatory bowel disease (IBD) is a chronic inflammatory intestinal disease, characterized by dysregulated immune response. HDAC3 is reported to be an epigenetic brake...
Inflammatory bowel disease (IBD) is a chronic inflammatory intestinal disease, characterized by dysregulated immune response. HDAC3 is reported to be an epigenetic brake in inflammation, playing critical roles in macrophages. However, its role in IBD is unclear. In our study, we found HDAC3 was upregulated in CX3CR1-positive cells in the mucosa from IBD mice. Conditional knockout (cKO) of Hdac3 in CX3CR1 positive cells attenuated the disease severity of Dextran Sulfate Sodium (DSS)-induced colitis. In addition, inhibition of HDAC3 with RGFP966 could also alleviate the DSS-induced tissue injury and inflammation in IBD. The RNA sequencing results revealed that Hdac3 cKO restrained DSS-induced upregulation of genes in the pathways of cytokine-cytokine receptor interaction, complement and coagulation cascades, chemokine signaling, and extracellular matrix receptor interaction. We also identified that Guanylate-Binding Protein 5 (GBP5) was transcriptionally regulated by HDAC3 in monocytes by RNA sequencing. Inhibition of HDAC3 resulted in decreased transcriptional activity of interferon-gamma-induced expression of GBP5 in CX3CR1-positive cells, such as macrophages and microglia. Overexpression of HDAC3 upregulated the transcriptional activity of GBP5 reporter. Lastly, conditional knockout of Hdac3 in macrophages (Hdac3 mKO) attenuated the disease severity of DSS-induced colitis. In conclusion, inhibition of HDAC3 in macrophages could ameliorate the disease severity and inflammatory response in colitis by regulating GBP5-NLRP3 axis, identifying a new therapeutic avenue for the treatment of colitis.
Topics: Animals; Dextran Sulfate; Histone Deacetylases; Mice; Macrophages; NLR Family, Pyrin Domain-Containing 3 Protein; Mice, Knockout; Colitis; Humans; Signal Transduction; Inflammatory Bowel Diseases; GTP-Binding Proteins; Disease Models, Animal; CX3C Chemokine Receptor 1; Mice, Inbred C57BL; Histone Deacetylase Inhibitors; Intestinal Mucosa; Acrylamides; Phenylenediamines
PubMed: 38903915
DOI: 10.7150/ijms.94592 -
Asian Journal of Pharmaceutical Sciences Jun 2024Polyamine metabolism dysregulation is a hallmark of many cancers, offering a promising avenue for early tumor theranostics. This study presents the development of a...
Polyamine metabolism dysregulation is a hallmark of many cancers, offering a promising avenue for early tumor theranostics. This study presents the development of a nuclear probe derived from spermidine (SPM) for dual-purpose tumor PET imaging and internal radiation therapy. The probe, radiolabeled with either [Ga]Ga for diagnostic applications or [Lu]Lu for therapeutic use, was synthesized with exceptional purity, stability, and specific activity. Extensive testing involving 12 different tumor cell lines revealed remarkable specificity towards B16 melanoma cells, showcasing outstanding tumor localization and target-to-non-target ratio. Mechanistic investigations employing polyamines, non-labeled precursor, and polyamine transport system (PTS) inhibitor, consistently affirmed the probe's targetability through recognition of the PTS. Notably, while previous reports indicated PTS upregulation in various tumor types for targeted therapy, this study observed no positive signals, highlighting a concentration-dependent discrepancy between targeting for therapy and diagnosis. Furthermore, when labeled with [Lu], the probe demonstrated its therapeutic potential by effectively controlling tumor growth and extending mouse survival. Investigations into biodistribution, excretion, and biosafety in healthy humans laid a robust foundation for clinical translation. This study introduces a versatile SPM-based nuclear probe with applications in precise tumor theranostics, offering promising prospects for clinical implementation.
PubMed: 38903130
DOI: 10.1016/j.ajps.2024.100924 -
Blood Jun 2024
Azab AK, Runnels JM, Pitsillides C, et al. CXCR4 inhibitor AMD3100 disrupts the interaction of multiple myeloma cells with the bone marrow microenvironment and enhances their sensitivity to therapy. Blood. 2009;113(18):4341-4351.
Topics: Cyclams; Humans; Multiple Myeloma; Receptors, CXCR4; Benzylamines; Heterocyclic Compounds; Bone Marrow; Tumor Microenvironment
PubMed: 38900482
DOI: 10.1182/blood.2024025275 -
Mikrochimica Acta Jun 2024Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-CN nanosheets,...
Ratiometric fluorescence and colorimetric strategies for assessing activity of butyrylcholinesterase in human serum using g-CN nanosheets, silver ion and o-phenylenediamine.
Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-CN nanosheets, silver ion (Ag) and o-phenylenediamine (OPD) as chromogenic agents. The oxidation-reduction reaction of OPD and Ag generates 2,3-diaminophenazine (oxOPD). Under exciation at 370 nm, g-CN nanosheets and oxOPD emit fluorescence at 440 nm (F) and 560 nm (F), respectively. Additionally, oxOPD exhibits quenching ability towards g-CN nanosheets via photoinduced electron transfer (PET) process. Thiocholine (TCh), as a product of BChE-catalyzed hydrolysis reaction of butylthiocholine iodide (BTCh), can coordinate with Ag intensively, and consequently diminish the amount of free Ag in the testing system. Less amount of free Ag leads to less production of oxOPD, resulting in less fluorescence quenching towards g-CN nanosheets as well as less fluorescence emission of oxOPD. Therefore, by using g-CN nanosheets and oxOPD as fluorescence indicators, the intensity ratio of their fluorescence (F/F) was calculated and employed to evaluate the activity of BChE. Similarly, the color variation of oxOPD indicated by the absorbance at 420 nm (ΔA) was monitored for the same purpose. These strategies were validated to be sensitive and selective for detecting BChE activity in human serum, with limits of detection (LODs) of 0.1 U L for ratiometric fluorescence mode and 0.7 U L for colorimetric mode.
Topics: Humans; Colorimetry; Silver; Phenylenediamines; Butyrylcholinesterase; Spectrometry, Fluorescence; Nanostructures; Nitrogen Compounds; Limit of Detection; Nitriles; Graphite; Phenazines
PubMed: 38900245
DOI: 10.1007/s00604-024-06488-w -
Trends in Endocrinology and Metabolism:... Jun 2024Intracellular metabolism is a crucial regulator of macrophage function. Recent evidence revealed that the polyamine pathway and subsequent hypusination of eukaryotic... (Review)
Review
Intracellular metabolism is a crucial regulator of macrophage function. Recent evidence revealed that the polyamine pathway and subsequent hypusination of eukaryotic initiation factor 5A (eIF5A) are master regulators of immune cell functions. In brown adipose tissue (BAT), macrophages show an impressive degree of heterogenicity, with specific subsets supporting adaptive thermogenesis during cold exposure. In this review, we discuss the impact of polyamine metabolism on macrophage diversity and function, with a particular focus on their role in adipose tissue homeostasis. Thus, we highlight the exploration of how polyamine metabolism in macrophages contributes to BAT homeostasis as an attractive and exciting new field of research.
PubMed: 38897879
DOI: 10.1016/j.tem.2024.05.008