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1.
Bioorg Chem ; 149: 107509, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38824699

RESUMO

In mammals, nicotinamide phosphoribosyltransferase (NAMPT) is a crucial enzyme in the nicotinamide adenine dinucleotide (NAD+) synthesis pathway catalyzing the condensation of nicotinamide (NAM) with 5-phosphoribosyl-1-pyrophosphate (PRPP) to produce nicotinamide mononucleotide (NMN). Given the pivotal role of NAD+ in a range of cellular functions, including DNA synthesis, redox reactions, cytokine generation, metabolism, and aging, NAMPT has become a promising target for many diseases, notably cancer. Therefore, various NAMPT inhibitors have been reported and classified as first and second-generation based on their chemical structures and design strategies, dual-targeted being one. However, most NAMPT inhibitors suffer from several limitations, such as dose-dependent toxicity and poor pharmacokinetic properties. Consequently, there is no clinically approved NAMPT inhibitor. Hence, research on discovering more effective and less toxic dual-targeted NAMPT inhibitors with desirable pharmacokinetic properties has drawn attention recently. This review summarizes the previously reported dual-targeted NAMPT inhibitors, focusing on their design strategies and advantages over the single-targeted therapies.


Assuntos
Antineoplásicos , Inibidores Enzimáticos , Neoplasias , Nicotinamida Fosforribosiltransferase , Animais , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Estrutura Molecular , Neoplasias/tratamento farmacológico , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Relação Estrutura-Atividade , NAD/química , NAD/metabolismo , Niacinamida/química
2.
Langmuir ; 40(25): 13144-13154, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38869442

RESUMO

Reduced nicotinamide adenine dinucleotide (NADH)-detecting electrochemical sensors are attractive in monitoring and diagnosing various physiological disorders of NADH abnormalities. The NADH detection methods using conventional electrodes are challenging due to slow electron transfer and fouling effect. Interestingly, paper-based flexible and disposable electrodes (PE) are superior for sensing biomolecules through simple detection procedures with excellent sensitivity and selectivity. Herein, to construct a conducting polypeptide-modified paper electrode, initially, polytyrosine (PTyr) is synthesized from l-tyrosine N-carboxy anhydride through ring-opening polymerization, and PTyr is drop-coated on the PE. The PTyr-modified paper electrode (PMPE) demonstrated excellent electrochemical properties and facilitated the electrooxidation of NADH at a lower potential of 576 mV. The PMPE displayed a linear detection between 25 and 145 µM of NADH concentration, with a lower detection limit of 0.340 µM. Under ideal circumstances, the sensor developed displayed an excellent NADH detection capability without interference with the most common electroactive species, ascorbic acid. The PMPE facilitates good electrocatalytic activity toward NADH, which can also be employed as a substrate material for biofuel cells.


Assuntos
Eletrodos , NAD , Papel , NAD/análise , NAD/química , Peptídeos/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Oxirredução , Limite de Detecção , Técnicas Biossensoriais/métodos
3.
Nat Commun ; 15(1): 4900, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851775

RESUMO

Excitation energy transfer (EET) is a key photoinduced process in biological chromophoric assemblies. Here we investigate the factors which can drive EET into efficient ultrafast sub-ps regimes. We demonstrate how a coherent transport of electronic population could facilitate this in water solvated NADH coenzyme and uncover the role of an intermediate dark charge-transfer state. High temporal resolution ultrafast optical spectroscopy gives a 54±11 fs time constant for the EET process. Nonadiabatic quantum dynamical simulations computed through the time-evolution of multidimensional wavepackets suggest that the population transfer is mediated by photoexcited molecular vibrations due to strong coupling between the electronic states. The polar aqueous solvent environment leads to the active participation of a dark charge transfer state, accelerating the vibronically coherent EET process in favorably stacked conformers and solvent cavities. Our work demonstrates how the interplay of structural and environmental factors leads to diverse pathways for the EET process in flexible heterodimers and provides general insights relevant for coherent EET processes in stacked multichromophoric aggregates like DNA strands.


Assuntos
Transferência de Energia , NAD , NAD/química , NAD/metabolismo , Teoria Quântica , Água/química
4.
Chem Commun (Camb) ; 60(46): 5932-5935, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38757567

RESUMO

A novel NIR fluorescent probe based on quinoline-conjugated benzo[cd]indol dual-salt for NADH was developed. This probe swiftly detects and responds sensitively to both endogenous and exogenous NADH alterations, enabling imaging of NADH fluctuations in type II diabetic and AD model cells.


Assuntos
Corantes Fluorescentes , Mitocôndrias , NAD , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , NAD/análise , NAD/química , Mitocôndrias/metabolismo , Mitocôndrias/química , Humanos , Quinolinas/química , Raios Infravermelhos , Imagem Óptica , Animais , Diabetes Mellitus Tipo 2
5.
Bioorg Chem ; 147: 107418, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703441

RESUMO

A key approach in developing green chemistry involves converting solar energy into chemical energy of biomolecules through photocatalysis. Photocatalysis can facilitate the regeneration of nicotinamide cofactors during redox processes. Nicotinamide cofactor biomimetics (NCBs) are economical substitutes for natural cofactors. Here, photocatalytic regeneration of NADH and reduced NCBs (NCBsred) using graphitic carbon nitride (g-C3N4) was developed. The process involves g-C3N4 as the photocatalyst, Cp*Rh(bpy)H2O2+ as the electron mediator, and Triethanolamine as the electron donor, facilitating the reduction of NAD+ and various oxidative NCBs (NCBsox) under light irradiation. Notably, the highest reduction yield of 48.32 % was achieved with BANA+, outperforming the natural cofactor NAD+. Electrochemical analysis reveals that the reduction efficiency and capacity of cofactors relies on their redox potentials. Additionally, a coupled photo-enzymatic catalysis system was explored for the reduction of 4-Ketoisophorone by Old Yellow Enzyme XenA. Among all the NCBsox and NAD+, the highest conversion ratio of over 99 % was obtained with BANA+. After recycled for 8 times, g-C3N4 maintained over 93.6 % catalytic efficiency. The photocatalytic cofactor regeneration showcases its outstanding performance with NAD+ as well as NCBsox. This work significantly advances the development of photocatalytic cofactor regeneration for artificial cofactors and its potential application.


Assuntos
Biocatálise , Oxirredução , Processos Fotoquímicos , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Estrutura Molecular , NAD/química , NAD/metabolismo , Biomimética , Niacinamida/química , Niacinamida/metabolismo , Compostos de Nitrogênio/química , Grafite
6.
Biochemistry ; 63(10): 1347-1358, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38691339

RESUMO

The physiological role of dihydroorotate dehydrogenase (DHOD) enzymes is to catalyze the oxidation of dihydroorotate to orotate in pyrimidine biosynthesis. DHOD enzymes are structurally diverse existing as both soluble and membrane-associated forms. The Family 1 enzymes are soluble and act either as conventional single subunit flavin-dependent dehydrogenases known as Class 1A (DHODA) or as unusual heterodimeric enzymes known as Class 1B (DHODB). DHODBs possess two active sites separated by ∼20 Å, each with a noncovalently bound flavin cofactor. NAD is thought to interact at the FAD containing site, and the pyrimidine substrate is known to bind at the FMN containing site. At the approximate center of the protein is a single Fe2S2 center that is assumed to act as a conduit, facilitating one-electron transfers between the flavins. We present anaerobic transient state analysis of a DHODB enzyme from Lactoccocus lactis. The data presented primarily report the exothermic reaction that reduces orotate to dihydroorotate. The reductive half reaction reveals rapid two-electron reduction that is followed by the accumulation of a four-electron reduced state when NADH is added in excess, suggesting that the initial two electrons acquired reside on the FMN cofactor. Concomitant with the first reduction is the accumulation of a long-wavelength absorption feature consistent with the blue form of a flavin semiquinone. Spectral deconvolution and fitting to a model that includes reversibility for the second electron transfer reveals equilibrium accumulation of a flavin bisemiquinone state that has features of both red and blue semiquinones. Single turnover reactions with limiting NADH and excess orotate reveal that the flavin bisemiquinone accumulates with reduction of the enzyme by NADH and decays with reduction of the pyrimidine substrate, establishing the bisemiquinone as a fractional state of the two-electron reduced intermediate observed.


Assuntos
Di-Hidro-Orotato Desidrogenase , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/química , Lactococcus lactis/enzimologia , Lactococcus lactis/metabolismo , Oxirredução , Domínio Catalítico , Cinética , Mononucleotídeo de Flavina/metabolismo , Mononucleotídeo de Flavina/química , NAD/metabolismo , NAD/química , Catálise , Flavinas/metabolismo , Biocatálise , Flavina-Adenina Dinucleotídeo/metabolismo , Flavina-Adenina Dinucleotídeo/química
7.
J Biol Inorg Chem ; 29(4): 455-475, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38780762

RESUMO

Ferritins are multimeric nanocage proteins that sequester/concentrate excess of free iron and catalytically synthesize a hydrated ferric oxyhydroxide bio-mineral. Besides functioning as the primary intracellular iron storehouses, these supramolecular assemblies also oversee the controlled release of iron to meet physiologic demands. By virtue of the reducing nature of the cytosol, reductive dissolution of ferritin-iron bio-mineral by physiologic reducing agents might be a probable pathway operating in vivo. Herein, to explore this reductive iron-release pathway, a series of quinone analogs differing in size, position/nature of substituents and redox potentials were employed to relay electrons from physiologic reducing agent, NADH, to the ferritin core. Quinones are well known natural electron/proton mediators capable of facilitating both 1/2 electron transfer processes and have been implicated in iron/nutrient acquisition in plants and energy transduction. Our findings on the structure-reactivity of quinone mediators highlight that iron release from ferritin is dictated by electron-relay capability (dependent on E1/2 values) of quinones, their molecular structure (i.e., the presence of iron-chelation sites and the propensity for H-bonding) and the type/amount of reactive oxygen species (ROS) they generate in situ. Juglone/Plumbagin released maximum iron due to their intermediate E1/2 values, presence of iron chelation sites, the ability to inhibit in situ generation of H2O2 and form intramolecular H-bonding (possibly promotes semiquinone formation). This study may strengthen our understanding of the ferritin-iron-release process and their significance in bioenergetics/O2-based cellular metabolism/toxicity while providing insights on microbial/plant iron acquisition and the dynamic host-pathogen interactions.


Assuntos
Ferritinas , Ferro , NAD , Oxirredução , Quinonas , Espécies Reativas de Oxigênio , Ferritinas/química , Ferritinas/metabolismo , Ferro/metabolismo , Ferro/química , NAD/metabolismo , NAD/química , Oxigênio/metabolismo , Oxigênio/química , Quinonas/química , Quinonas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Mycobacterium
8.
Chemistry ; 30(35): e202400411, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38640109

RESUMO

Nicotinamide adenine dinucleotide (NAD+) is a redox active molecule that is universally found in biology. Despite the importance and simplicity of this molecule, few reports exist that investigate which molecular features are important for the activity of this ribodinucleotide. By exploiting the nonenzymatic reduction and oxidation of NAD+ by pyruvate and methylene blue, respectively, we were able to identify key molecular features necessary for the intrinsic activity of NAD+ through kinetic analysis. Such features may explain how NAD+ could have been selected early during the emergence of life. Simpler molecules, such as nicotinamide, that lack an anomeric carbon are incapable of accepting electrons from pyruvate. The phosphate moiety inhibits activity in the absence of metal ions but facilitates activity at physiological pH and model prebiotic conditions by recruiting catalytic Mg2+. Reduction proceeds through consecutive single electron transfer events. Of the derivatives tested, including nicotinamide mononucleotide, nicotinamide riboside, 3-(aminocarbonyl)-1-(2,3-dihydroxypropyl)pyridinium, 1-methylnicotinamide, and nicotinamide, only NAD+ and nicotinamide mononucleotide would be capable of efficiently accepting and donating electrons within a nonenzymatic electron transport chain. The data are consistent with early metabolic chemistry exploiting NAD+ or nicotinamide mononucleotide and not simpler molecules.


Assuntos
Magnésio , NAD , Niacinamida , Oxirredução , NAD/química , NAD/metabolismo , Magnésio/química , Niacinamida/química , Niacinamida/análogos & derivados , Sítios de Ligação , Cinética , Mononucleotídeo de Nicotinamida/química , Mononucleotídeo de Nicotinamida/metabolismo , Compostos de Piridínio/química , Azul de Metileno/química , Ácido Pirúvico/química , Ácido Pirúvico/metabolismo , Transporte de Elétrons
9.
J Mol Graph Model ; 130: 108778, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38652998

RESUMO

SIRT6 is of interest for its promising effect in the treatment of aging-related diseases. Studies have shown quercetin (QUE) and its derivatives have varying degrees of effect on the catalytic effect of SIRT6. In the research, the effect of QUE on the protein-substrate interaction in the SIRT6-mediated mono-ADP ribosylation system was investigated by conventional molecular dynamics (MD) simulations combined with MM/PBSA binding free energy calculations. The results show that QUE can bind stably to SIRT6 with the binding energy of -22.8 kcal/mol and further affect the atomic interaction between SIRT6 and NAD+ (or H3K9), resulting in an increased affinity between SIRT6-NAD+ and decreased SIRT6-H3K9 binding capacity. At the same time, the binding of QUE can also alter some structural characteristics of the protein, with large shifts occurring in the residue regions involving the N-terminal (residues 1-27), Rossmann fold regions (residues 55-92), and ZBD (residues 164-179). Thus, QUE shows great potential as a scaffold for the design of novel potent SIRT6 modulators.


Assuntos
Simulação de Dinâmica Molecular , Ligação Proteica , Quercetina , Sirtuínas , Quercetina/química , Quercetina/farmacologia , Sirtuínas/química , Sirtuínas/metabolismo , Humanos , Sítios de Ligação , NAD/química , NAD/metabolismo , Termodinâmica , Simulação de Acoplamento Molecular , Especificidade por Substrato , Ligação de Hidrogênio , Conformação Proteica
10.
Angew Chem Int Ed Engl ; 63(27): e202404024, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38641561

RESUMO

Here we demonstrate the preparation of enzyme-metal biohybrids of NAD+ reductase with biocatalytically-synthesised small gold nanoparticles (NPs, <10 nm) and core-shell gold-platinum NPs for tandem catalysis. Despite the variety of methods available for NP synthesis, there remains a need for more sustainable strategies which also give precise control over the shape and size of the metal NPs for applications in catalysis, biomedical devices, and electronics. We demonstrate facile biosynthesis of spherical, highly uniform, gold NPs under mild conditions using an isolated enzyme moiety, an NAD+ reductase, to reduce metal salts while oxidising a nicotinamide-containing cofactor. By subsequently introducing platinum salts, we show that core-shell Au@Pt NPs can then be formed. Catalytic function of these enzyme-Au@Pt NP hybrids was demonstrated for H2-driven NADH recycling to support enantioselective ketone reduction by an NADH-dependent alcohol dehydrogenase.


Assuntos
Biocatálise , Ouro , Nanopartículas Metálicas , NAD , Platina , Nanopartículas Metálicas/química , NAD/química , NAD/metabolismo , Ouro/química , Platina/química , Hidrogênio/química , Hidrogênio/metabolismo , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química , Oxirredução
11.
Colloids Surf B Biointerfaces ; 239: 113903, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38599036

RESUMO

Nicotinamide mononucleotide (NMN) is being investigated for its ability to address the decline in NAD+ level during aging. This study aimed to construct a delivery system based on ovalbumin and fucoidan nanoparticles to ameliorate the bioaccessibility of NMN by increasing NAD+ level in aging mouse model. The NMN-loaded ovalbumin and fucoidan nanoparticles (OFNPs) were about 177 nm formed by the interplay of hydrogen bonds between ovalbumin and fucoidan. Compared with free NMN, NMN-loaded OFNPs intervention could obviously improve the antioxidant enzyme activity of senescent cell induced by D-galactose. The NMN-loaded OFNPs treatment could ameliorate the loss of weight and organ index induced by senescence, and maintain the water content for the aging mice. The Morris maze test indicated that hitting blind side frequency and escape time of NMN-loaded OFNPs group decreased by 13% and 35% compared with that of free NMN group. Furthermore, the NMN-loaded OFNPs significantly alleviated the age-related oxidative stress and increased the generation of NAD+ 1.34 times by improving the bioaccessibility of NMN. Our data in this study supplied a strategy to enhance the bioavailability of NMN in senescence treatment.


Assuntos
Envelhecimento , Galactose , NAD , Nanopartículas , Mononucleotídeo de Nicotinamida , Polissacarídeos , Animais , Galactose/química , Nanopartículas/química , Camundongos , Envelhecimento/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/farmacologia , NAD/metabolismo , NAD/química , Mononucleotídeo de Nicotinamida/química , Mononucleotídeo de Nicotinamida/farmacologia , Tamanho da Partícula , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ovalbumina
12.
Langmuir ; 40(13): 6685-6693, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38525517

RESUMO

Understanding the mechanism of interfacial enzyme kinetics is critical to the development of synthetic biological systems for the production of value-added chemicals. Here, the interfacial kinetics of the catalysis of ß-nicotinamide adenine dinucleotide (NAD+)-dependent enzymes acting on NAD+ tethered to the surface of silica nanoparticles (SiNPs) has been investigated using two complementary and supporting kinetic approaches: enzyme excess and reactant (NAD+) excess. Kinetic models developed for these two approaches characterize several critical reaction steps including reversible enzyme adsorption, complexation, decomplexation, and catalysis of the surface-bound enzyme/NAD+ complex. The analysis reveals a concentrating effect resulting in a very high local concentration of enzyme and cofactor on the particle surface, in which the enzyme is saturated by surface-bound NAD, facilitating a rate enhancement of enzyme/NAD+ complexation and catalysis. This resulted in high enzyme efficiency within the tethered NAD+ system compared to that of the free enzyme/NAD+ system, which increases with decreasing enzyme concentration. The role of enzyme adsorption onto solid substrates with a tethered catalyst (such as NAD+) has potential for creating highly efficient flow biocatalytic systems.


Assuntos
NAD , NAD/química , Biocatálise , Catálise , Cinética , Adsorção
13.
Protein Sci ; 33(4): e4924, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38501590

RESUMO

Targeted delivery of small-molecule drugs via covalent attachments to monoclonal antibodies has proved successful in clinic. For this purpose, full-length antibodies are mainly used as drug-carrying vehicles. Despite their flexible conjugation sites and versatile biological activities, intact immunoglobulins with conjugated drugs, which feature relatively large molecular weights, tend to have restricted tissue distribution and penetration and low fractions of payloads. Linking small-molecule therapeutics to other formats of antibody may lead to conjugates with optimal properties. Here, we designed and synthesized ADP-ribosyl cyclase-enabled fragment antigen-binding (Fab) drug conjugates (ARC-FDCs) by utilizing CD38 catalytic activity. Through rapidly forming a stable covalent bond with a nicotinamide adenine dinucleotide (NAD+ )-based drug linker at its active site, CD38 genetically fused with Fab mediates robust site-specific drug conjugations via enzymatic reactions. Generated ARC-FDCs with defined drug-to-Fab ratios display potent and antigen-dependent cytotoxicity against breast cancer cells. This work demonstrates a new strategy for developing site-specific FDCs. It may be applicable to different antibody scaffolds for therapeutic conjugations, leading to novel targeted agents.


Assuntos
Antígenos CD , NAD+ Nucleosidase , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Antígenos CD/química , NAD+ Nucleosidase/química , Preparações Farmacêuticas , NAD/química
14.
Analyst ; 149(9): 2728-2737, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38525963

RESUMO

This work presents the synthesis and characterization of an innovative F,S-doped carbon dots/CuONPs hybrid nanostructure obtained by a direct mixture between F,S-doped carbon dots obtained electrochemically and copper nitrate alcoholic solution. The hybrid nanostructures synthesized were characterized by absorption spectroscopy in the Ultraviolet region (UV-vis), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and different electrochemical techniques. The fluoride and sulfur-doped carbon dots/CuONPs nanostructures were used to prepare a non-enzymatic biosensor on a printed carbon electrode, exhibiting excellent electrocatalytic activity for the simultaneous determination of NADH, dopamine, and uric acid in the presence of ascorbic acid with a detection limit of 20, 80, and 400 nmol L-1, respectively. The non-enzymatic biosensors were also used to determine NADH, dopamine, and uric acid in plasma, and they did not suffer significant interference from each other.


Assuntos
Técnicas Biossensoriais , Carbono , Cobre , Dopamina , Técnicas Eletroquímicas , Limite de Detecção , NAD , Ácido Úrico , Ácido Úrico/sangue , Ácido Úrico/química , Técnicas Biossensoriais/métodos , Dopamina/sangue , Dopamina/análise , Carbono/química , NAD/química , NAD/sangue , Cobre/química , Técnicas Eletroquímicas/métodos , Humanos , Enxofre/química , Fluoretos/química , Pontos Quânticos/química , Nanoestruturas/química , Eletrodos
15.
J Chromatogr A ; 1721: 464821, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38547681

RESUMO

Recent studies highlight the pivotal roles of Nicotinamide adenine dinucleotide (NAD+) and its metabolites in aging and neurodegeneration. Accurate quantification of NAD+ and its metabolite levels in cells or tissues is crucial for advancing biochemical research and interventions targeting aging and neurodegenerative diseases. This study presents an accurate, precise, and rapid LC-MS/MS method using a surrogate matrix to quantify endogenous substances NAD+, nicotinamide mononucleotide (NMN), nicotinamide (NAM), adenosine diphosphate ribose (ADPR), and cyclic adenosine diphosphate ribose (cADPR) concentrations in mice sciatic nerves. Considering the properties of the phosphate groups in the analytes, the column and mobile phase were systematically optimized. These five polar analytes exhibited excellent analytical performance and baseline separation within 5 min on an Atlantis Premier BEH C18 AX column, with methylene phosphonic acid as a mobile phase additive. Enhanced sensitivity addressed the challenges posed by the small sample size of mice sciatic nerve and low NMN and cADPR detection. The method was fully validated, with linear correlation coefficients exceeding 0.992, precision (%relative standard deviation, RSD) values within 8.8%, and accuracy values between 92.2% and 107.3%, suggesting good reproducibility. Analytical recoveries in spiked and diluted matrix ranged from 87.8% to 104.7%, indicating the suitability of water as a surrogate matrix. Application of the method to quantify NAD+ and its metabolite levels in normal and injured mice sciatic nerve identified cADPR as a sensitive biomarker in the nerve injury model. This method is anticipated to deepen our understanding of the connections between NAD+ and its metabolites in health and disease, potentially improving diagnoses of various neurological disorders and aiding drug development for aging and neurodegenerative diseases.


Assuntos
NAD , Doenças Neurodegenerativas , Camundongos , Animais , NAD/química , NAD/metabolismo , ADP-Ribose Cíclica , Cromatografia Líquida , Espectrometria de Massa com Cromatografia Líquida , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Nervo Isquiático/metabolismo
16.
Structure ; 32(5): 594-602.e4, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38460521

RESUMO

Apoptosis-inducing factor (AIF), which is confined to mitochondria of normal healthy cells, is the first identified caspase-independent cell death effector. Moreover, AIF is required for the optimal functioning of the respiratory chain machinery. Recent findings have revealed that AIF fulfills its pro-survival function by interacting with CHCHD4, a soluble mitochondrial protein which promotes the entrance and the oxidative folding of different proteins in the inner membrane space. Here, we report the crystal structure of the ternary complex involving the N-terminal 27-mer peptide of CHCHD4, NAD+, and AIF harboring its FAD (flavin adenine dinucleotide) prosthetic group in oxidized form. Combining this information with biophysical and biochemical data on the CHCHD4/AIF complex, we provide a detailed structural description of the interaction between the two proteins, validated by both chemical cross-linking mass spectrometry analysis and site-directed mutagenesis.


Assuntos
Fator de Indução de Apoptose , Domínio Catalítico , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas Mitocondriais , Modelos Moleculares , Ligação Proteica , Fator de Indução de Apoptose/metabolismo , Fator de Indução de Apoptose/química , Fator de Indução de Apoptose/genética , Humanos , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/genética , Regulação Alostérica , Cristalografia por Raios X , NAD/metabolismo , NAD/química , Sítios de Ligação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética
17.
Structure ; 32(6): 715-724.e3, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38503292

RESUMO

Energy-converting NADH:ubiquinone oxidoreductase, respiratory complex I, is a major enzyme of energy metabolism that couples NADH oxidation and ubiquinone reduction with proton translocation. The NADH oxidation site features different enzymatic activities with various nucleotides. While the kinetics of these reactions are well described, only binding of NAD+ and NADH have been structurally characterized. Here, we report the structures of the electron input module of Aquifex aeolicus complex I with bound ADP-ribose and 3-acetylpyridine adenine dinucleotides at resolutions better than 2.0 Å. ADP-ribose acts as inhibitor by blocking the "ADP-handle" motif essential for nucleotide binding. The pyridine group of APADH is minimally offset from flavin, which could contribute to its poorer suitability as substrate. A comparison with other nucleotide co-structures surprisingly shows that the adenine ribose and the pyrophosphate moiety contribute most to nucleotide binding, thus all adenine dinucleotides share core binding modes to the unique Rossmann-fold in complex I.


Assuntos
Adenosina Difosfato Ribose , Complexo I de Transporte de Elétrons , Modelos Moleculares , Ligação Proteica , Complexo I de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/química , Adenosina Difosfato Ribose/metabolismo , Adenosina Difosfato Ribose/química , Sítios de Ligação , NAD/metabolismo , NAD/química , Cristalografia por Raios X , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Oxirredução
18.
J Inorg Biochem ; 253: 112487, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38306887

RESUMO

Metal-dependent, nicotine adenine dinucleotide (NAD+)-dependent formate dehydrogenases (FDHs) are complex metalloenzymes coupling biochemical transformations through intricate electron transfer pathways. Rhodobacter capsulatus FDH is a model enzyme for understanding coupled catalysis, in that reversible CO2 reduction and formate oxidation are linked to a flavin mononuclotide (FMN)-bound diaphorase module via seven iron-sulfur (FeS) clusters as a dimer of heterotetramers. Catalysis occurs at a bis-metal-binding pterin (Mo) binding two molybdopterin guanine dinucleotides (bis-MGD), a protein-based Cys residue and a participatory sulfido ligand. Insights regarding the proposed electron transfer mechanism between the bis-MGD and the FMN have been complicated by the discovery that an alternative pathway might occur via intersubunit electron transfer between two [4Fe4S] clusters within electron transfer distance. To clarify this difference, the redox potentials of the bis-MGD and the FeS clusters were determined via redox titration by EPR spectroscopy. Redox potentials for the bis-MGD cofactor and five of the seven FeS clusters could be assigned. Furthermore, substitution of the active site residue Lys295 with Ala resulted in altered enzyme kinetics, primarily due to a more negative redox potential of the A1 [4Fe4S] cluster. Finally, characterization of the monomeric FdsGBAD heterotetramer exhibited slightly decreased formate oxidation activity and similar iron-sulfur clusters reduced relative to the dimeric heterotetramer. Comparison of the measured redox potentials relative to structurally defined FeS clusters support a mechanism by which electron transfer occurs within a heterotetrameric unit, with the interfacial [4Fe4S] cluster serving as a structural component toward the integrity of the heterodimeric structure to drive efficient catalysis.


Assuntos
Formiato Desidrogenases , NAD , NAD/química , Formiato Desidrogenases/química , Elétrons , Oxirredução , Ferro/química , Enxofre/química , Formiatos
19.
Small ; 20(26): e2311027, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38263719

RESUMO

Nanozyme-based metabolic regulation triggered by tumor-specific endogenous stimuli has emerged as a promising therapeutic strategy for tumors. The current efficacy, however, is constrained by the limited concentration of endogenous substrates and the metabolic plasticity of tumors. Consequently, the implementation of efficient metabolic regulation in tumor therapy is urgently needed. Herein, a versatile nanozyme-based nicotinamide adenine dinucleotide (NADH) circulating oxidation nanoreactor is reported. First, the synthesized cobalt-doped hollow carbon spheres (Co-HCS) possess NADH oxidase (NOX)-mimicking activity for the NADH oxidation to disrupt oxidative phosphorylation (OXPHOS) pathway of tumor cells. Second, the substrate-cycle manner of Co-HCS can be used for NADH circulating oxidation to overcome the limitation of substrate deficiency. Finally, 2-Deoxy-D-glucose (2-DG) and 6-aminonicotinamide (6-AN) are introduced to block glycolysis and pentose phosphate pathway (PPP), thus creating a versatile nanozyme-based NADH circulating oxidation nanoreactor (Co-HCS/D/A) for tumor therapy through triple cellular metabolism disruption. In vitro and in vivo results demonstrate that the designed nanoreactor not only enhances the catalytic efficiency but also disrupts the tumor metabolic homeostasis, leading to efficient therapy outcome. This study develops a novel NADH circulating oxidation nanoreactor for tumor therapy through triple cellular metabolism disruption, which addresses the limitations of current nanozyme-based metabolism regulation for tumor therapy.


Assuntos
NAD , Oxirredução , NAD/metabolismo , NAD/química , Humanos , Animais , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Linhagem Celular Tumoral , Camundongos
20.
Small ; 20(25): e2309487, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38197548

RESUMO

Cellular senescence, a vulnerable state of growth arrest, has been regarded as a potential strategy to weaken the resistance of tumor cells, leading to dramatic improvements in treatment efficacy. However, a selective and efficient strategy for inducing local tumor cellular senescence has not yet been reported. Herein, piezoelectric catalysis is utilized to reduce intracellular NAD+ to NADH for local tumor cell senescence for the first time. In detail, a biocompatible nanomedicine (BTO/Rh-D@M) is constructed by wrapping the piezoelectric BaTiO3/(Cp*RhCl2)2 (BTO/Rh) and doxorubicin (DOX) in the homologous cytomembrane with tumor target. After tumors are stimulated by ultrasound, negative and positive charges are generated on the BTO/Rh by piezoelectric catalysis, which reduce the intracellular NAD+ to NADH for cellular senescence and oxidize H2O to reactive oxygen species (ROS) for mitochondrial damage. Thus, the therapeutic efficacy of tumor immunogenic cell death-induced chemo-immunotherapy is boosted by combining cellular senescence, DOX, and ROS. The results indicate that 23.9% of the piezoelectric catalysis-treated tumor cells senesced, and solid tumors in mice disappeared completely after therapy. Collectively, this study highlights a novel strategy to realize cellular senescence utilizing piezoelectric catalysis and the significance of inducing tumor cellular senescence to improve therapeutic efficacy.


Assuntos
Senescência Celular , Doxorrubicina , Imunoterapia , Espécies Reativas de Oxigênio , Senescência Celular/efeitos dos fármacos , Animais , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Catálise , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Imunoterapia/métodos , NAD/metabolismo , NAD/química , Linhagem Celular Tumoral , Humanos , Titânio/química , Titânio/farmacologia , Neoplasias/terapia , Neoplasias/patologia , Neoplasias/tratamento farmacológico , Ródio/química , Ródio/farmacologia , Compostos de Bário
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