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1.
J Cell Sci ; 137(3)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345344

RESUMO

The 2'-O-methylation (2'-O-Me) of ribosomal RNA (rRNA) shows plasticity that is potentially associated with cell phenotypes. We used RiboMeth-seq profiling to reveal growth arrest-specific 2'-O-Me patterns in primary human dermal fibroblasts from three different donors. We exposed cells to hydrogen peroxide to induce cellular senescence and to high cell densities to promote quiescence by contact inhibition. We compared both modes of cell cycle arrest to proliferating cells and could indeed distinguish these conditions by their overall 2'-O-Me patterns. Methylation levels at a small fraction of sites showed plasticity and correlated with the expression of specific small nucleolar RNAs (snoRNAs) but not with expression of fibrillarin. Moreover, we observed subtle senescence-associated alterations in ribosome biogenesis. Knockdown of the snoRNA SNORD87, which acts as a guide for modification of a hypermethylated position in non-proliferating cells, was sufficient to boost cell proliferation. Conversely, depletion of SNORD88A, SNORD88B and SNORD88C, which act as guides for modification of a hypomethylated site, caused decreased proliferation without affecting global protein synthesis or apoptosis. Taken together, our findings provide evidence that rRNA modifications can be used to distinguish and potentially influence specific growth phenotypes of primary cells.


Assuntos
RNA Ribossômico , Ribose , Humanos , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Ribose/metabolismo , Ribossomos/metabolismo , Metilação , RNA Nucleolar Pequeno/genética , Fibroblastos/metabolismo
2.
Mol Biol Rep ; 51(1): 220, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281218

RESUMO

D-ribose, an ubiquitous pentose compound found in all living cells, serves as a vital constituent of numerous essential biomolecules, including RNA, nucleotides, and riboflavin. It plays a crucial role in various fundamental life processes. Within the cellular milieu, exogenously supplied D-ribose can undergo phosphorylation to yield ribose-5-phosphate (R-5-P). This R-5-P compound serves a dual purpose: it not only contributes to adenosine triphosphate (ATP) production through the nonoxidative phase of the pentose phosphate pathway (PPP) but also participates in nucleotide synthesis. Consequently, D-ribose is employed both as a therapeutic agent for enhancing cardiac function in heart failure patients and as a remedy for post-exercise fatigue. Nevertheless, recent clinical studies have suggested a potential link between D-ribose metabolic disturbances and type 2 diabetes mellitus (T2DM) along with its associated complications. Additionally, certain in vitro experiments have indicated that exogenous D-ribose exposure could trigger apoptosis in specific cell lines. This article comprehensively reviews the current advancements in D-ribose's digestion, absorption, transmembrane transport, intracellular metabolic pathways, impact on cellular behaviour, and elevated levels in diabetes mellitus. It also identifies areas requiring further investigation.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Doenças Metabólicas , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ribose/metabolismo , Trifosfato de Adenosina
3.
RNA Biol ; 21(1): 1-10, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38117089

RESUMO

Pseudouridine is a noncanonical C-nucleoside containing a C-C glycosidic linkage between uracil and ribose. In the two-step degradation of pseudouridine, pseudouridine 5'-monophosphate glycosylase (PUMY) is responsible for the second step and catalyses the cleavage of the C-C glycosidic bond in pseudouridine 5'-monophosphate (ΨMP) into uridine and ribose 5'-phosphate, which are recycled via other metabolic pathways. Structural features of Escherichia coli PUMY have been reported, but the details of the substrate specificity of ΨMP were unknown. Here, we present three crystal structures of Arabidopsis thaliana PUMY in different ligation states and a kinetic analysis of ΨMP degradation. The results indicate that Thr149 and Asn308, which are conserved in the PUMY family, are structural determinants for recognizing the nucleobase of ΨMP. The distinct binding modes of ΨMP and ribose 5'-phosphate also suggest that the nucleobase, rather than the phosphate group, of ΨMP dictates the substrate-binding mode. An open-to-close transition of the active site is essential for catalysis, which is mediated by two α-helices, α11 and α12, near the active site. Mutational analysis validates the proposed roles of the active site residues in catalysis. Our structural and functional analyses provide further insight into the enzymatic features of PUMY towards ΨMP.


Assuntos
Arabidopsis , Pseudouridina , Pseudouridina/metabolismo , Cinética , Ribose/metabolismo , Escherichia coli/metabolismo , Nucleosídeos/metabolismo , Fosfatos , Catálise , Especificidade por Substrato , Cristalografia por Raios X
4.
Mar Drugs ; 21(11)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-37999422

RESUMO

Two new compounds, named rhizoaspergillin A (1) and rhizoaspergillinol A (2), were isolated from the mangrove endophytic fungus Aspergillus sp. A1E3, associated with the fruit of Rhizophora mucronata, together with averufanin (3). The planar structures and absolute configurations of rhizoaspergillinol A (2) and averufanin (3) were established by extensive NMR investigations and quantum-chemical electronic circular dichroism (ECD) calculations. Most notably, the constitution and absolute configuration of rhizoaspergillin A (1) were unambiguously determined by single-crystal X-ray diffraction analysis of its tri-pivaloyl derivative 4, conducted with Cu Kα radiation, whereas those of averufanin (3) were first clarified by quantum-chemical ECD calculations. Rhizoaspergillin A is the first orsellinic acid-ribose-pyridazinone-N-oxide hybrid containing a unique ß-oxo-2,3-dihydropyridazine 1-oxide moiety, whereas rhizoaspergillinol A (2) and averufanin (3) are sterigmatocystin and anthraquinone derivatives, respectively. From the perspective of biosynthesis, rhizoaspergillin A (1) could be originated from the combined assembly of three building blocks, viz., orsellinic acid, ß-D-ribofuranose, and L-glutamine. It is an unprecedented alkaloid-N-oxide involving biosynthetic pathways of polyketides, pentose, and amino acids. In addition, rhizoaspergillinol A (2) exhibited potent antiproliferative activity against four cancer cell lines. It could dose-dependently induce G2/M phase arrest in HepG2 cells.


Assuntos
Aspergillus , Ribose , Ribose/metabolismo , Aspergillus/química , Antraquinonas/metabolismo , Estrutura Molecular
5.
Biochem Biophys Res Commun ; 682: 187-192, 2023 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-37820454

RESUMO

d-Allose is an aldohexose of the C3-epimer of d-glucose, existing in very small amounts in nature, called a rare sugar. The operon responsible for d-allose metabolism, the allose operon, was found in several bacteria, which consists of seven genes: alsR, alsB, alsA, alsC, alsE, alsK, and rpiB. To understand the biological implication of the allose operon utilizing a rare sugar of d-allose as a carbon source, it is important to clarify whether the allose operon functions specifically for d-allose or also functions for other ligands. It was proposed that the allose operon can function for d-ribose, which is essential as a component of nucleotides and abundant in nature. Allose-binding protein, AlsB, coded in the allose operon, is thought to capture a ligand outside the cell, and is expected to show high affinity for the specific ligand. X-ray structure determinations of Enterobacter cloacae AlsB (EtcAlsB) in ligand-free form, and in complexes with d-allose, d-ribose, and d-allulose, and measurements of the thermal parameters of the complex formation using an isothermal titration calorimeter were performed. The results demonstrated that EtcAlsB has a unique recognition mechanism for high affinity to d-allose by changing its conformation from an open to a closed form depending on d-allose-binding, and that the binding of d-ribose to EtcAlsB could not induce a completely closed form but an intermediate form, explaining the low affinity for d-ribose.


Assuntos
Proteínas de Transporte , Monossacarídeos , Proteínas de Transporte/metabolismo , Enterobacter cloacae/genética , Enterobacter cloacae/metabolismo , Raios X , Ligantes , Ribose/metabolismo , Glucose/metabolismo
6.
Methods Mol Biol ; 2701: 21-38, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37574473

RESUMO

APE1 (apurinic/apyrimidinic endodeoxyribonuclease 1) is a central enzyme of the base excision repair (BER) pathway playing a pivotal role in protecting mammalian cells against genotoxins and in safeguarding genome stability. Recently, we demonstrated the APE1 ability to process abasic ribonucleotides embedded in DNA. Here, we provide a pipeline of protocols to quantify endodeoxyribonuclease activity by APE1 on these substrates, by using recombinant protein and whole-cell extracts. The repair capacity is measured by using fluorescent oligonucleotide substrates, which are then separated by polyacrylamide gel electrophoresis and detected by imaging scanning. The specificity of APE1 action is demonstrated using specific APE1 enzymatic inhibitors.


Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Ensaios Enzimáticos , Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/análise , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Ensaios Enzimáticos/métodos , Ribose/metabolismo , Técnicas In Vitro
7.
Reprod Domest Anim ; 58(10): 1379-1392, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37592767

RESUMO

The present study evaluated the seminal plasma metabolome of Bos indicus Guzerá bulls with good (n = 4) and poor (n = 5) sperm freezability. Animals were raised in natural pasture of a 'Caatinga' ecosystem, in the semi-arid region of Brazil. Seminal plasma samples were subjected to gas chromatography coupled to mass spectrometry and data, analysed using bioinformatics tools (Cytoscape with the MetScape plug-in). Sixty-two metabolites were identified in the bovine seminal plasma. Fatty acids and conjugates and organic compounds were the predominant seminal fluid metabolites, followed by carboxylic acids and derivatives, amino acids, benzenes and steroids and derivatives, carbohydrates and carbohydrate conjugates and prenol lipids. Multivariate analysis indicated a distinct separation of seminal plasma metabolomes from bulls with contrasting sperm freezability. Abundances of propanoic acid, d-ribose and glycine were greater in the seminal plasma of bulls with good sperm freezability. Heptadecanoic acid and undecanoic acid were the predominant in bulls of poor sperm freezability. Propanoic acid is an energy source for spermatozoa and may act as an antimicrobial component in semen. Glycine acts against oxidizing and denaturing reactions. d-ribose is also an energy source and reduces apoptosis and oxidative stress. Undecanoic acid may protect sperm against fungal damage. This study provides fundamental information approximately the seminal plasma metabolome of tropically adapted bulls and its association with sperm freezability. However, further studies with larger groups of animals are needed to validate those metabolites as markers of sperm freezability. This strategy could support the selection of sires with superior sperm cryoresistance.


Assuntos
Propionatos , Sêmen , Bovinos , Animais , Masculino , Sêmen/química , Propionatos/análise , Propionatos/metabolismo , Ecossistema , Ribose/análise , Ribose/metabolismo , Espermatozoides , Fenótipo , Glicina
8.
Nat Metab ; 5(5): 765-776, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198474

RESUMO

Glucose is vital for life, serving as both a source of energy and carbon building block for growth. When glucose is limiting, alternative nutrients must be harnessed. To identify mechanisms by which cells can tolerate complete loss of glucose, we performed nutrient-sensitized genome-wide genetic screens and a PRISM growth assay across 482 cancer cell lines. We report that catabolism of uridine from the medium enables the growth of cells in the complete absence of glucose. While previous studies have shown that uridine can be salvaged to support pyrimidine synthesis in the setting of mitochondrial oxidative phosphorylation deficiency1, our work demonstrates that the ribose moiety of uridine or RNA can be salvaged to fulfil energy requirements via a pathway based on: (1) the phosphorylytic cleavage of uridine by uridine phosphorylase UPP1/UPP2 into uracil and ribose-1-phosphate (R1P), (2) the conversion of uridine-derived R1P into fructose-6-P and glyceraldehyde-3-P by the non-oxidative branch of the pentose phosphate pathway and (3) their glycolytic utilization to fuel ATP production, biosynthesis and gluconeogenesis. Capacity for glycolysis from uridine-derived ribose appears widespread, and we confirm its activity in cancer lineages, primary macrophages and mice in vivo. An interesting property of this pathway is that R1P enters downstream of the initial, highly regulated steps of glucose transport and upper glycolysis. We anticipate that 'uridine bypass' of upper glycolysis could be important in the context of disease and even exploited for therapeutic purposes.


Assuntos
Ribose , Uridina , Ribose/metabolismo , Uridina/metabolismo , RNA/metabolismo , Glicólise , Humanos , Linhagem Celular Tumoral , Fosforilação Oxidativa , Meios de Cultura , Glucose , Células K562 , Proliferação de Células , Via de Pentose Fosfato
9.
Nature ; 618(7963): 151-158, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37198494

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease notoriously resistant to therapy1,2. This is mediated in part by a complex tumour microenvironment3, low vascularity4, and metabolic aberrations5,6. Although altered metabolism drives tumour progression, the spectrum of metabolites used as nutrients by PDA remains largely unknown. Here we identified uridine as a fuel for PDA in glucose-deprived conditions by assessing how more than 175 metabolites impacted metabolic activity in 21 pancreatic cell lines under nutrient restriction. Uridine utilization strongly correlated with the expression of uridine phosphorylase 1 (UPP1), which we demonstrate liberates uridine-derived ribose to fuel central carbon metabolism and thereby support redox balance, survival and proliferation in glucose-restricted PDA cells. In PDA, UPP1 is regulated by KRAS-MAPK signalling and is augmented by nutrient restriction. Consistently, tumours expressed high UPP1 compared with non-tumoural tissues, and UPP1 expression correlated with poor survival in cohorts of patients with PDA. Uridine is available in the tumour microenvironment, and we demonstrated that uridine-derived ribose is actively catabolized in tumours. Finally, UPP1 deletion restricted the ability of PDA cells to use uridine and blunted tumour growth in immunocompetent mouse models. Our data identify uridine utilization as an important compensatory metabolic process in nutrient-deprived PDA cells, suggesting a novel metabolic axis for PDA therapy.


Assuntos
Glucose , Neoplasias Pancreáticas , Ribose , Microambiente Tumoral , Uridina , Animais , Camundongos , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Ribose/metabolismo , Uridina/química , Glucose/deficiência , Divisão Celular , Linhagem Celular Tumoral , Sistema de Sinalização das MAP Quinases , Uridina Fosforilase/deficiência , Uridina Fosforilase/genética , Uridina Fosforilase/metabolismo , Humanos
10.
Arterioscler Thromb Vasc Biol ; 43(6): 927-942, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37078291

RESUMO

BACKGROUND: Endothelial cell activation is tightly controlled by the balance between VEGF (vascular endothelial cell growth factor) and Notch signaling pathway. VEGF destabilizes blood vessels and promotes neovascularization, which are common features of sight-threatening ocular vascular disorders. Here, we show that BCL6B (B-cell CLL/lymphoma 6 member B protein), also known as BAZF, ZBTB28, and ZNF62, plays a pivotal role in the development of retinal edema and neovascularization. METHODS: The pathophysiological physiological role of BCL6B was investigated in cellular and animal models mimicking 2 pathological conditions: retinal vein occlusion and choroidal neovascularization. An in vitro experimental system was used in which human retinal microvascular endothelial cells were supplemented with VEGF. Choroidal neovascularization cynomolgus monkey model was generated to investigate the involvement of BCL6B in the pathogenesis. Mice lacking BCL6B or treated with BCL6B-targeting small-interfering ribose nucleic acid were examined for histological and molecular phenotypes. RESULTS: In retinal endothelial cells, the BCL6B expression level was increased by VEGF. BCL6B-deficient endothelial cells showed Notch signal activation and attenuated cord formation via blockage of the VEGF-VEGFR2 signaling pathway. Optical coherence tomography images showed that choroidal neovascularization lesions were decreased by BCL6B-targeting small-interfering ribose nucleic acid. Although BCL6B mRNA expression was significantly increased in the retina, BCL6B-targeting small-interfering ribose nucleic acid suppressed ocular edema in the neuroretina. The increase in proangiogenic cytokines and breakdown of the inner blood-retinal barrier were abrogated in BCL6B knockout (KO) mice via Notch transcriptional activation by CBF1 (C promotor-binding factor 1) and its activator, the NICD (notch intracellular domain). Immunostaining showed that Müller cell activation, a source of VEGF, was diminished in BCL6B-KO retinas. CONCLUSIONS: These data indicate that BCL6B may be a novel therapeutic target for ocular vascular diseases characterized by ocular neovascularization and edema.


Assuntos
Neovascularização de Coroide , Ácidos Nucleicos , Neovascularização Retiniana , Doenças Vasculares , Animais , Humanos , Camundongos , Neovascularização de Coroide/genética , Neovascularização de Coroide/metabolismo , Células Endoteliais/metabolismo , Macaca fascicularis/metabolismo , Ácidos Nucleicos/metabolismo , Ácidos Nucleicos/uso terapêutico , Neovascularização Retiniana/genética , Neovascularização Retiniana/metabolismo , Ribose/metabolismo , Ribose/uso terapêutico , Doenças Vasculares/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Infect Disord Drug Targets ; 23(5): e090323214508, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36892121

RESUMO

BACKGROUND: Tuberculosis is the second leading cause of death from infectious diseases worldwide. Multidrug-resistant Mycobacterium tuberculosis is spreading throughout the world, creating a crisis. Hence, there is a need to develop anti-tuberculosis drugs with novel structures and versatile mechanisms of action. OBJECTIVE: In this study, we identified antimicrobial compounds with a novel skeleton that inhibits mycobacterium decaprenylphosphoryl-ß-D-ribose oxidase (DprE1). METHODS: A multi-step, in silico, structure-based drug screening identified potential DprE1 inhibitors from a library of 154,118 compounds. We experimentally verified the growth inhibitory effects of the eight selected candidate compounds against Mycobacterium smegmatis. Molecular dynamics simulations were performed to understand the mechanism of molecular interactions between DprE1 and ompound 4. RESULTS: Eight compounds were selected through in silico screening. Compound 4 showed strong growth inhibition against M. smegmatis. Molecular dynamics simulation (50 ns) predicted direct and stable binding of Compound 4 to the active site of DprE1. CONCLUSION: The structural analysis of the novel scaffold in Compound 4 can pave way for antituberculosis drug development and discovery.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Oxirredutases/metabolismo , Oxirredutases/farmacologia , Ribose/metabolismo , Ribose/farmacologia , Antituberculosos/farmacologia , Antituberculosos/química , Proteínas de Bactérias/metabolismo
12.
Cell Death Dis ; 14(1): 50, 2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681688

RESUMO

Parthanatos is one of the major pathways of programmed cell death in ischemic stroke characterized by DNA damage, poly (ADP-ribose) polymerases (PARP) activation, and poly (ADP-ribose) (PAR) formation. Here we demonstrate that crocetin, a natural potent antioxidant compound from Crocus sativus, antagonizes parthanatos in ischemic stroke. We reveal that mechanistically, crocetin inhibits NADPH oxidase 2 (NOX2) activation to reduce reactive oxygen species (ROS) and PAR production at the early stage of parthanatos. Meanwhile we demonstrate that PARylated hexokinase-I (HK-I) is a novel substrate of E3 ligase RNF146 and that crocetin interacts with HK-I to suppress RNF146-mediated HK-I degradation at the later stage of parthanatos, preventing mitochondrial dysfunction and DNA damage that ultimately trigger the irreversible cell death. Our study supports further development of crocetin as a potential drug candidate for preventing and/or treating ischemic stroke.


Assuntos
AVC Isquêmico , Parthanatos , Humanos , Hexoquinase/metabolismo , NADPH Oxidase 2/metabolismo , AVC Isquêmico/metabolismo , Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Mitocôndrias/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo
13.
Blood Cells Mol Dis ; 99: 102725, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682143

RESUMO

d-Ribose is not only an important component of some biomacromolecules, but also an active pentose with strong reducibility and non-enzymatic glycation ability. Previous studies reported the diverse role of d-ribose in different cells. In this study, the effects of d-ribose on non-enzymatic glycation of hemoglobin (Hb), as well as eryptosis, oxidative stress and energy metabolism of erythrocytes were observed by molecular fluorescence spectrophotometry, multi-wavelength spectrophotometry, high-pressure liquid chromatography (HPLC), mass spectrometry (MS) and flow cytometer. The results showed that d-ribose had the strongest non-enzymatic glycation ability to Hb in vitro when compared with other monosaccharides, and could enter the erythrocytes in a concentration-dependent manner, which was not inhibited by the specific glucose transporter 1 (GLUT1) inhibitor WZB117. In addition, d-ribose incubation increased the HbA1c, hemolysis, eryptosis, and ROS level of erythrocytes significantly more than that of d-glucose, however, no changes were observed in the levels of ATP, NADPH, and other intermediate energy metabolites in d-ribose treatment. Therefore, the strong non-enzymatic glycation ability of d-ribose may play an important role in erythrocyte damage.


Assuntos
Eriptose , Humanos , Ribose/química , Ribose/metabolismo , Ribose/farmacologia , Reação de Maillard , Eritrócitos/metabolismo , Estresse Oxidativo , Hemoglobinas/metabolismo , Metabolismo Energético , Cálcio/metabolismo , Fosfatidilserinas/metabolismo
14.
Epilepsia Open ; 8 Suppl 1: S25-S34, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35278284

RESUMO

Excitotoxicity is the underlying mechanism for all acute neuronal injury, from cerebral ischemia, status epilepticus, traumatic CNS injury, and hypoglycemia. It causes morphological neuronal necrosis, and it triggers a programmed cell death program. Excessive calcium entry through the NMDA-receptor-operated cation channel activates two key enzymes-calpain I and neuronal nitric oxide synthase (nNOS). Calpain I, a cytosolic enzyme, translocates to mitochondrial and lysosomal membranes, causing release of cytochrome c, endonuclease G, and apoptosis-inducing factor (AIF) from mitochondria and DNase II and cathepsins B and D from lysosomes. These all translocate to neuronal nuclei, creating DNA damage, which activates poly(ADP) ribose polymerase-1 (PARP-1) to form excessive amounts of poly(ADP) ribose (PAR) polymers, which translocate to mitochondrial membranes, causing release of truncated AIF (tAIF). The free radicals that are released from mitochondria and peroxynitrite, formed from nitric oxide (NO) from nNOS catalysis of L-arginine to L-citrulline, damage mitochondrial and lysosomal membranes and DNA. The end result is the necrotic death of neurons. Another programmed necrotic pathway, necroptosis, occurs through a parallel pathway. As investigators of necroptosis do not recognize the excitotoxic pathway, it is unclear to what extent each contributes to programmed neuronal necrosis. We are studying the extent to which each contributes to acute neuronal necrosis and the extent of cross-talk between these pathways.


Assuntos
Poli(ADP-Ribose) Polimerases , Estado Epiléptico , Humanos , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Calpaína/metabolismo , Ribose/metabolismo , Necrose/metabolismo , Neurônios/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Membranas Mitocondriais/metabolismo , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo
15.
Biomolecules ; 12(12)2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36551203

RESUMO

Reports concerning the beneficial effects of D-ribose administration in cardiovascular and muscle stressful conditions has led to suggestions for the use of ribose as an energizing food supplement for healthy people. However, this practice still presents too many critical issues, suggesting that caution is needed. In fact, there are many possible negative effects of this sugar that we believe are underestimated, if not neglected, by the literature supporting the presentation of the product to the market. Here, the risks deriving from the use of free ribose as ATP source, forcing ribose-5-phosphate to enter into the pentose phosphate pathway, is emphasized. On the basis of the remarkable glycation capacity of ribose, the easily predictable cytotoxic effect of the molecule is also highlighted.


Assuntos
Via de Pentose Fosfato , Ribose , Humanos , Ribose/metabolismo
16.
PLoS One ; 17(12): e0267329, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36584038

RESUMO

Poly (ADP-ribose) polymerase (PARP) is responsible for the synthesis of ADP-ribose polymers, which are involved in a wide range of cellular processes such as preservation of genome integrity, DNA damage signaling and repair, molecular switches between distinct cell death pathways, and cell cycle progression. Previously, we demonstrated that the only PARP present in T. cruzi migrates to the nucleus upon genotoxic stimulus. In this work, we identify the N-terminal domain as being sufficient for TcPARP nuclear localization and describe for the first time that TcPARP is enriched in the parasite's nucleolus. We also describe that TcPARP is present in a thread-like structure that connects two dividing nuclei and co-localizes with nucleolar material and microtubules. Furthermore, ADP-ribose polymers could also be detected in this thread during mitosis. These findings represent a first approach to new potential TcPARP functions inside the nucleus and will help understand its role well beyond the largely described DNA damage response protein in trypanosomatids.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Inibidores de Poli(ADP-Ribose) Polimerases , Ribose/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Núcleo Celular/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Dano ao DNA , Adenosina Difosfato Ribose/metabolismo , Mitose , Doença de Chagas/metabolismo
17.
Commun Biol ; 5(1): 1290, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36434094

RESUMO

Bacteria and Eucarya utilize the non-oxidative pentose phosphate pathway to direct the ribose moieties of nucleosides to central carbon metabolism. Many archaea do not possess this pathway, and instead, Thermococcales utilize a pentose bisphosphate pathway involving ribose-1,5-bisphosphate (R15P) isomerase and ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco). Intriguingly, multiple genomes from halophilic archaea seem only to harbor R15P isomerase, and do not harbor Rubisco. In this study, we identify a previously unrecognized nucleoside degradation pathway in halophilic archaea, composed of guanosine phosphorylase, ATP-dependent ribose-1-phosphate kinase, R15P isomerase, RuBP phosphatase, ribulose-1-phosphate aldolase, and glycolaldehyde reductase. The pathway converts the ribose moiety of guanosine to dihydroxyacetone phosphate and ethylene glycol. Although the metabolic route from guanosine to RuBP via R15P is similar to that of the pentose bisphosphate pathway in Thermococcales, the downstream route does not utilize Rubisco and is unique to halophilic archaea.


Assuntos
Ribose , Ribulose-Bifosfato Carboxilase , Ribulose-Bifosfato Carboxilase/genética , Ribulose-Bifosfato Carboxilase/metabolismo , Ribose/metabolismo , Pentoses/metabolismo , Archaea/genética , Archaea/metabolismo , Guanosina/metabolismo , Fosfatos
18.
BMC Biotechnol ; 22(1): 29, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36221128

RESUMO

BACKGROUND: In the search for methods to biodegrade recalcitrant compounds, the use of saprotrophic fungi and white rot fungi, in particular belonging to the phylum Basidiomycota, has gained interest. This group of fungi possesses a battery of unspecific extracellular enzymes that can be utilized in the biodegradation of preferably phenolic compounds. In this work, it was investigated under which conditions the white rot fungus Trametes versicolor and the ericoid mycorrhizal fungus Rhizoscyphus ericae (belonging to the phylum Ascomycota) could be used to biodegrade the antibiotic aminoglycoside neomycin at co-metabolic conditions in which external nutrients were supplied. Furthermore, it was also investigated whether a biodegradation could be accomplished using neomycin as the sole nutrient. RESULTS: The results show that both species can biodegrade neomycin 70% under co-metabolic conditions during a one-week time course and that Rhizoscyphus ericae is able to use neomycin as sole nutrient and to approximatively biodegrade it 60% under chosen non co-metabolic conditions. At selected conditions, the biodegradation of neomycin using Rhizoscyphus ericae was monitored by oxidation products of D-ribose which is a hydrolysis product of neomycin. CONCLUSION: The results are of general interest in the search for fungal species that can biodegrade recalcitrant compounds without the need of external nutrients. The key future application area that will be investigated is purification of waste from recombinant protein production in which neomycin, nutrients and E. coli with neomycin resistance genes are present.


Assuntos
Micorrizas , Antibacterianos/metabolismo , Ascomicetos , Biodegradação Ambiental , Escherichia coli , Micorrizas/metabolismo , Neomicina/metabolismo , Proteínas Recombinantes/metabolismo , Ribose/metabolismo , Trametes
19.
Cell Biochem Funct ; 40(7): 784-796, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36128730

RESUMO

Biosynthetic procedure is one of the best alternatives, inexpensive and ecologically sound for the synthesis of titanium dioxide (TiO2 ) nanoparticles using a methanolic extract of medicinal plant. The main prospect of this study was to investigate the antiglycation activity of the TiO2 nanoparticles (TNP) prepared by ethanolic leaf extract of the Coleus scutellarioides. In this study, biosynthesized TNP characterized with UV-Visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscope. These TNP were further investigated with respect to their antiglycation property and it was checked in the mixture of d-ribose glycated bovine serum albumin (BSA) by measuring ketoamine, carbonyl content, Advanced glycation end products (AGEs) and aggregation of protein instigated by glycation process. The inhibitory effect of TNP to restore the structure of BSA in presence of d-ribose were also characterize by biophysical techniques mentioned above. Therefore, the findings of this study suggest repurposing of TNP for its antiglycation property that could be helpful in prevention of glycation instigated AGEs formation and structural loss of proteins.


Assuntos
Nanopartículas , Soroalbumina Bovina , Produtos Finais de Glicação Avançada/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ribose/química , Ribose/metabolismo , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Titânio
20.
Cell Biochem Funct ; 40(7): 729-741, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36098489

RESUMO

The generation of advanced glycation end products (AGEs) through nonenzymatic protein glycation contributes to the pathogenesis of long-lived diabetic problems. Metformin (MTF) is the very first drug having antihyperglycemic effects on type II diabetes mellitus which also possess interaction with dicarbonyl compounds and blocks the formation of AGEs. In the current study, MTF is bioconjugated with glycation-derived synthesized gold nanoparticles (GNPs) of significant size. Additionally, using various biophysical and biochemical approaches, we investigated the antiglycating capacity MTF-GNPs in contrast to MTF against d-ribose-derived glycation of bovine serum albumin. Our key findings via utilizing various assays demonstrated that MTF-GNPs were able to inhibit AGEs development by reducing hyperchromicity, early glycation products, carbonyl content, hydxoxymethylfurfural content, production of fluorescent AGEs, normalizing the loss of secondary structure (i.e., α-helix and ß-sheets) of proteins, elevating the levels of free lysine and free arginine more efficiently compared to pure MTF. Based on these results, we concluded that MTF-GNPs possess a considerable antiglycation property and may be developed as an outstanding anti-AGEs treatment drug. Further in vivo and clinical research are necessary to determine the therapeutic effects of MTF-GNPs against AGE-related and metabolic disorders.


Assuntos
Diabetes Mellitus Tipo 2 , Nanopartículas Metálicas , Metformina , Arginina , Diabetes Mellitus Tipo 2/tratamento farmacológico , Produtos Finais de Glicação Avançada/metabolismo , Ouro , Humanos , Hipoglicemiantes/farmacologia , Lisina/química , Metformina/farmacologia , Ribose/química , Ribose/metabolismo , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
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