RESUMO
Methods for producing drugs directly at the cancer site, particularly using bioorthogonal metal catalysts, are being explored to mitigate the side effects of therapy. Albumin-based artificial metalloenzymes (ArMs) catalyze reactions in living mice while protecting the catalyst in the hydrophobic pocket. Here, we describe the in situ preparation and application of biocompatible tumor-targeting ArMs using circulating albumin, which is abundant in the bloodstream. The ArM was formed using blood albumin through the intravenous injection of ruthenium conjugated with an albumin-binding ligand; the tumor-targeting unit was conjugated to the ArM using its catalytic activity, and the ArM was transported to the cancer site. The delivered ArM catalyzed a second tagging reaction of the proapoptotic peptide on the cancer surface, successfully suppressing cancer proliferation. This approach, which efficiently leveraged the persisting reactivity twice in vivo, holds promise for future in vivo metal-catalyzed drug synthesis utilizing endogenous albumin.
RESUMO
N-alkyl unsaturated imines derived from acrolein, a toxin produced during oxidative stress, and biogenic alkyl amines occur naturally and are considered biologically relevant compounds. However, despite the recent conceptual and technological advances in organic synthesis, research on the new reactivity of these compounds is lacking. This personal account discusses research on the reactivity that has been overlooked in acrolein imines, including the discovery of new methods to synthesize biologically active compounds, the determination of new functions of relevant imines and their precursors, i. e., aldehydes and amines, and the application of these methods for clinical diagnosis.
Assuntos
Acroleína/química , Doença de Alzheimer/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Iminas/química , Acroleína/síntese química , Feminino , Humanos , Iminas/síntese química , Estrutura Molecular , Estresse OxidativoRESUMO
Amyloid aggregates of proteins are known to be involved in various diseases such as Alzheimer's disease (AD). It is therefore speculated that the inhibition of amyloid formation can play an important role in the prevention of various diseases involving amyloids. Recently, we have found that acrolein reacts with polyamines, such as spermine, and produces 1,5-diazacyclooctane, such as cyclic spermine (cSPM). cSPM could suppress the aggregation of amyloid ß 1-40 (Aß40), one of the causative proteins of AD. This result suggests the potential inhibitory effect of cSPM against Aß 1-42 (Aß42) and other amyloid protein aggregation which are the main pathological features of AD and other diseases. However, the effect on the aggregation of such proteins remains unclear. In this study, the effect of cSPM on the amyloid formation of Aß42, amylin, and insulin was investigated. These three amyloidogenic proteins forming amyloids under physiological conditions (pH 7.4 and 37â) served as model and are thought to be the causative proteins of AD, type 2 diabetes, and insulin-derived amyloidosis, respectively. Our results indicate that cSPM can suppress the amyloid aggregation of these proteins and reduce cytotoxicity. This study contributes to a better understanding of means to potentially counteract diseases by the means of polyamine and acrolein.
Assuntos
Acroleína/farmacologia , Compostos Aza/farmacologia , Ciclo-Octanos/farmacologia , Espermina/farmacologia , Acroleína/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Compostos Aza/síntese química , Compostos Aza/química , Ciclo-Octanos/síntese química , Ciclo-Octanos/química , Relação Dose-Resposta a Droga , Humanos , Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/antagonistas & inibidores , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Estrutura Molecular , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Espermina/química , Relação Estrutura-AtividadeRESUMO
Natural glycoconjugates that form glycocalyx play important roles in various biological processes based on cell surface recognition through pattern recognition mechanisms. This work represents a new synthesis-based screening strategy to efficiently target the cancer cells by higher-order glycan pattern recognition in both cells and intact animals (mice). The use of the very fast, selective, and effective RIKEN click reaction (6π-azaelectrocyclization of unsaturated imines) allows to synthesize and screen various structurally well-defined glycoalbumins containing two and eventually four different N-glycan structures in a very short time. The importance of glycan pattern recognition is exemplified in both cell- and mouse-based experiments. The use of pattern recognition mechanisms for cell targeting represents a novel and promising strategy for the development of diagnostic, prophylactic, and therapeutic agents for various diseases including cancers.
Assuntos
Neoplasias , Polissacarídeos , Animais , Produtos Finais de Glicação Avançada , Glicoconjugados , Camundongos , Albumina Sérica , Albumina Sérica GlicadaRESUMO
Acrolein, a highly reactive α,ß-unsaturated aldehyde, is a compound to which humans are exposed in many different situations and often causes various human diseases. This paper summarizes the reports over the past twenty-five years regarding disease-associated acrolein detected in clinical patients and the role acrolein plays in various diseases. In several diseases, it was found that the increased acrolein acts as a pathogenetic factor. Thus, we propose the utility of over-produced acrolein as a substrate for a promising therapeutic or diagnostic method applicable to a wide range of diseases based on an in vivo synthetic chemistry strategy.
Assuntos
Acroleína/química , Doença de Alzheimer/diagnóstico , Doenças Autoimunes/diagnóstico , Encefalopatias/diagnóstico , Acroleína/análise , Acroleína/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Doenças Autoimunes/terapia , Encefalopatias/terapia , Humanos , Lisina/análogos & derivados , Lisina/sangue , Lisina/líquido cefalorraquidiano , Lisina/química , Lisina/urina , Poliaminas/química , Proteínas/químicaRESUMO
Imine is one of the most versatile functional groups in chemistry and biochemistry fields. Although many biochemical reactions involve imine formation, the inherently unstable property of N-alkyl-α,ß-unsaturated imines still hindered their utilization in organic synthesis. In this article, we described that the N-alkyl-α,ß-unsaturated imines, which prepared from alkylamines and acrolein, could smoothly react through [4 + 4] cycloaddition to give eight-membered diazacyclooctane derivatives in excellent yields. Under a similar condition, in the presence of formaldehyde, the [4 + 2] and [4 + 2 + 2] cycloadditions could lead to the formation of six-membered hexahydropyrimidine or eight-membered triazacyclooctanes, depending on the substituent of aldehydes. Moreover, an easy functional group manipulation of the cyclic products obtained from these cycloadditions can provide variously substituted chiral linear diamines. We can utilize these novel reactivities to reveal the unknown and essential properties of many biological processes that involve N-alkyl-unsaturated imines.
RESUMO
Tetramethylrhodamine (TAMRA)-phenyl azide is a chemical probe used to detect intracellular acrolein directly in live cells. Herein, we demonstrated that TAMRA is the optimum fluorophore for the probe. TAMRA-phenyl azide was used to reveal that high levels of acrolein are generated in a variety of breast cancer cells, regardless of the tumor subtype. These findings corroborate the analysis presented in our previous report, in which TAMRA-phenyl azide was used to label breast cancer tissues resected from breast cancer patients. Because high levels of acrolein were generated in all cancer cell types, we believe that acrolein detection may be useful as a general method for labeling cancerous tissues.
Assuntos
Acroleína/análise , Azidas/química , Corantes Fluorescentes/química , Rodaminas/química , Acroleína/química , Biomarcadores/análise , Biomarcadores/química , Neoplasias da Mama/diagnóstico por imagem , Linhagem Celular Tumoral , Reação de Cicloadição , Humanos , Microscopia de Fluorescência/métodos , Estresse OxidativoRESUMO
TRAF6 is highly expressed in many tumors and plays an important role in the immune system. The aim of this study is to confirm anti-tumor activities of all naturally occurring Cinchona alkaloids that have been screened using computational docking program, and to validate the accuracy and specificity of the RING domain of TRAF6 as a potential anti-tumor target, and to explore their effect on the immune system. Results reported herein would demonstrate that Cinchona alkaloids could induce apoptosis in HeLa cells, inhibit the ubiquitination and phosphorylation of both AKT and TAK1, and up-regulate the ratio of Bax/Bcl-2. In addition, these compounds could induce apoptosis in vivo, and increase the secretion of TNF-α, IFN-γ, and IgG, while not significantly impacting the ratio of CD4+T/CD8+T. These investigations suggest that the RING domain of TRAF6 could serve as a de novo biological target for therapeutic treatment in cancers.
Assuntos
Apoptose/efeitos dos fármacos , Alcaloides de Cinchona/metabolismo , Alcaloides de Cinchona/farmacologia , Domínios Proteicos , Fator 6 Associado a Receptor de TNF/metabolismo , Animais , Ligação Competitiva , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática , Células HeLa , Humanos , Imunoglobulina G/sangue , Marcação In Situ das Extremidades Cortadas , Interferon gama/sangue , Peptídeos e Proteínas de Sinalização Intracelular , Contagem de Linfócitos , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Linfócitos T/efeitos dos fármacos , Fator 6 Associado a Receptor de TNF/química , Fator de Necrose Tumoral alfa/sangue , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/metabolismoRESUMO
Radiolabeled biomolecules with short half-life times are of increasing importance for positron emission tomography (PET) imaging studies. Herein, we demonstrate an improved and generalized method for synthesizing a [radiometal]-unsaturated aldehyde as a lysine-labeling probe that can be easily conjugated into various biomolecules through the RIKEN click reaction. As a case study, 68 Ga-PET imaging of U87MG xenografted mice is demonstrated by using the 68 Ga-DOTA-RGDyK peptide, which is selective to αV ß3 integrins.
Assuntos
Radioisótopos de Gálio/farmacocinética , Peptídeos/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Animais , Linhagem Celular Tumoral , Radioisótopos de Gálio/química , Xenoenxertos , Humanos , Integrina alfaVbeta3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/química , Distribuição TecidualRESUMO
Non-enzymatic glycation between proteins and carbohydrates, such as advanced glycation end products (AGEs), are naturally occurring compounds implicated in aging and numerous degenerative diseases. Methyl glyoxal (MG), which is an intermediate of the AGE biosynthetic pathway, is known to react with primary amines of proteins to create a wide range of AGE modifications, such as carboxyethyl lysine (CEL) and methylglyoxal-derived lysine dimer (MOLD). As a means to investigate and probe the ROS production pathways of AGEs, low molecular weight compounds carboxyethyl spermine (CES) and methylglyoxal-derived spermine dimer (MOSD) were synthesized, which replace lysine with another highly nucleophilic biological amine, spermine (SPM). Contrary to expectations, results show CES- and MOSD-induced oxidative stress proceeds through different pathways. As such, we have developed useful probes that can be used to better understand and investigate pathways related to acrolein-based oxidative stress and/or polyamine metabolic pathways.
RESUMO
Metal complex catalysis within biological systems is largely limited to cell and bacterial systems. In this work, a glycoalbumin-AuIII complex was designed and developed that enables organ-specific, localized propargyl ester amidation with nearby proteins within live mice. The targeted reactivity can be imaged through the use of Cy7.5- and TAMRA-linked propargyl ester based fluorescent probes. This targeting system could enable the exploitation of other metal catalysis strategies for biomedical and clinical applications.
Assuntos
Complexos de Coordenação/química , Corantes Fluorescentes/química , Ouro/química , Albumina Sérica/química , Animais , Catálise , Complexos de Coordenação/farmacocinética , Corantes Fluorescentes/farmacocinética , Produtos Finais de Glicação Avançada , Ouro/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Imagem Óptica/métodos , Albumina Sérica/farmacocinética , Distribuição Tecidual , Albumina Sérica GlicadaRESUMO
Peptidoglycan (PGN) is a major component of bacterial cell wall and is recognized as a potent immunostimulant. The PGN in the cell envelope of Mycobacterium Tuberculosis has been shown to possess several unique characteristics including the presence of N-glycolyl groups (in addition to N-acetyl groups) in the muramic acid residues, and amidation of the free carboxylic acid of d-Glu or of meso-DAP in the peptide chains. Using a newly developed, highly stereoselective, chemoenzymatic approach for the synthesis of meso-DAP in peptide stems, we successfully synthesized for the first time, a series of Mycobacterium PGN fragments that include both mono- and disaccharides of MurNGlyc or 1,6-anhydro-MurNGlyc, as well as peptide-amidated variants. The ability of these PGN fragments to stimulate the immune system through activation of human Nod1 and Nod2 was examined. The PGN fragments were found to modulate immune stimulation, specifically, amidation at the d-Glu and meso-DAP in the peptide stem strongly reduced hNod1 activation. This effect was dependent on modification position. Additionally, N-glycolyl (instead of acetyl) of muramic acid was associated with slightly reduced human Nod1 and Nod2 stimulatory capabilities.
Assuntos
Ácido Diaminopimélico/farmacologia , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Mycobacterium tuberculosis/química , Peptidoglicano/imunologia , Ácido Diaminopimélico/química , Ácido Diaminopimélico/metabolismo , Células HEK293 , Humanos , Conformação Molecular , Mycobacterium tuberculosis/imunologia , Proteína Adaptadora de Sinalização NOD1/antagonistas & inibidores , Proteína Adaptadora de Sinalização NOD1/imunologia , Proteína Adaptadora de Sinalização NOD2/antagonistas & inibidores , Proteína Adaptadora de Sinalização NOD2/imunologia , Peptidoglicano/biossíntese , Peptidoglicano/química , Relação Estrutura-AtividadeRESUMO
A general probe designed to induce a cascading sequence of reactions on a target protein was efficiently synthesized. The cascading reaction sequence involved (i) ligand-directed azaelectrocyclization with lysine and (ii) the autooxidation-induced release of a fluorescence quencher from the labeled protein. The probe was linked to a cyclic RGDyK peptide to enable the selective visualization of integrin αVß3 on the surfaces of live cells.
Assuntos
Compostos Aza/química , Fluorescência , Corantes Fluorescentes/química , Proteínas/química , Animais , Compostos Aza/síntese química , Linhagem Celular , Sobrevivência Celular , Ciclização , Corantes Fluorescentes/síntese química , Humanos , Ligantes , Camundongos , Modelos Moleculares , Estrutura Molecular , Oxirredução , Peptídeos Cíclicos/química , Propriedades de SuperfícieRESUMO
This study proposes a new method for radionuclide therapy that involves the use of oligomeric 2,6-diisopropylphenyl azides and a chelator to form stable complexes with metallic radionuclides. The technique works by taking advantage of the endogenous acrolein produced by cancer cells. The azides react with the acrolein to give a diazo derivative that immediately attaches to the nearest organelle, effectively anchoring the radionuclide within the tumor. Preliminary in vivo experiments were conducted on a human lung carcinoma xenograft model, demonstrating the feasibility of this approach for cancer treatment.
Assuntos
Azidas , Neoplasias , Humanos , Acroleína , RadioisótoposRESUMO
Cells are covered with a thick layer of sugar molecules known as glycans. Abnormal glycosylation is a hallmark of cancer, and hypersialylation increases tumor metastasis by promoting immune evasion and inducing tumor cell invasion and migration. Inhibiting sialylation is thus a potential anticancer treatment strategy. However, targeting sialic acids is difficult because of the lack of selective delivery tools. Here, we present a prodrug strategy for selectively releasing the global inhibitor of sialylation peracetylated 3Fax-Neu5Ac (PFN) in cancer cells using the reaction between phenyl azide and endogenous acrolein, which is overproduced in most cancer cells. The prodrug significantly suppressed tumor growth in mice as effectively as PFN without causing kidney dysfunction, which is associated with PFN. The use of sialylated glycans as immune checkpoints is gaining increasing attention, and the proposed method for precisely targeting aberrant sialylation provides a novel avenue for expanding current cancer treatments.
RESUMO
The unsaturated ester aldehyde, (E)-3-alkoxycarbonyl-5-phenyl-2,4-dienal, was efficiently dimerized by applying the strain-promoted double-click reaction with sym-dibenzo-1,5-cyclooctadiene-3,7-diyne. The resulting dimerized probe was sequentially reacted first with one peptide molecule and then with a protein or the amino groups on the surface of a live cell through double azaelectrocyclization to achieve highly efficient bioconjugation.
Assuntos
Aldeídos/química , Alcinos/química , Animais , Sobrevivência Celular , Ciclização , Dimerização , Ésteres , Células HeLa , Humanos , Camundongos , Peptídeos/química , Albumina Sérica/químicaRESUMO
Targeted α-particle therapy (TAT) is an attractive alternative to conventional therapy for cancer treatment. Among the available radionuclides considered for TAT, astatine-211 (211At) attached to a cancer-targeting molecule appears very promising. Previously, we demonstrated that aryl azide derivatives could react selectively with the endogenous acrolein generated by cancer cells to give a diazo compound, which subsequently forms a covalent bond with the organelle of cancer cells in vivo. Herein, we synthesized 211At-radiolabeled 2,6-diisopropylphenyl azide (ADIPA), an α-emitting molecule that can selectively target the acrolein of cancer cells, and investigated its antitumor effect. Our results demonstrate that a single intratumor or intravenous administration of this simple α-emitting molecule to the A549 (human lung cancer) cell-bearing xenograft mouse model, at a low dose (70 kBq), could suppress tumor growth without inducing adverse effects. Furthermore, because acrolein is generally overproduced by most cancer cells, we believe ADIPA is a simple TAT compound that deserves further investigation for application in animal models and humans with various cancer types and stages.
RESUMO
Nucleotide-binding oligomerization domain protein 1 (Nod1) is an intracellular protein involved in recognition of the bacterial component peptidoglycan. This recognition event induces a host defense response to eliminate invading pathogens. The genetic variation of Nod1 has been linked to several inflammatory diseases and allergies, which are strongly affected by environmental factors. We have found that many of the bacteria that contain DAP-type peptidoglycan release Nod1 ligands into the environment. However, the structures of natural Nod1 ligands in the environment are not well understood. Herein, we report the isolation and structural elucidation of natural human Nod1 (hNod1) ligands from the Escherichia coli K-12 culture supernatant. The supernatant was fractionated with reversed-phase high performance liquid chromatography (RP-HPLC), resulting in the isolation of several hNod1 stimulatory fractions. Structural characterization studies demonstrated that the molecular structure of the most active fraction was the native hNod1 ligand GlcNAc-(beta1-4)-(anhydro)MurNAc-l-Ala-gamma-d-Glu-meso-DAP. We also found other peptidoglycan fragments using the 7-(diethylamino)coumarin-3-carbonyl labeling method to enhance sensitivity in mass spectroscopy studies. These results suggested that DAP-containing bacteria release certain hNod1 ligands to the environment, and these ligands would accumulate in the environment and regulate the immune system through Nod1.
Assuntos
Escherichia coli/metabolismo , Proteína Adaptadora de Sinalização NOD1/metabolismo , Nucleotídeos/química , Bioensaio/métodos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Sistema Imunitário , Inflamação , Ligantes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Peptídeos/química , Peptidoglicano/química , Ligação Proteica , Estrutura Terciária de ProteínaRESUMO
Acrolein holds excellent potential as a biomarker in various oxidative stress-related diseases, including cancer, Alzheimer's, Parkinson's, and inflammatory disorders. Consequently, a direct method to target and visualize acrolein in biological systems might be essential to provide tools for diagnosis and therapeutic purposes. Previously, we discovered 1,3-dipolar cycloaddition between aryl azides and acrolein, which proceeds without a catalyst to give α-diazocarbonyl derivatives. The reaction proceeds with high reactivity and selectivity even under physiological conditions. We have successfully utilized the reaction as a robust method for detecting acrolein generated by cancer cells. This review discusses the utilization of the endogenous acrolein reaction with aryl azide to (1) distinguish breast cancer from normal tissue during breast-conserving surgery and (2) treat cancer through selective prodrug activation in a mouse model without causing adverse effects. The methods have potential clinical application for breast-conserving surgery and are highly advantageous for cancer therapy.
Assuntos
Acroleína/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama , Imagem Óptica , Pró-Fármacos/uso terapêutico , Animais , Antineoplásicos/química , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Pró-Fármacos/químicaRESUMO
Cytotoxic anticancer drugs used in chemotherapy are often antiproliferative agents that preferentially kill rapidly growing cancer cells. Their mechanism relies mainly on the enhanced proliferation rate of cancer cells and is not genuinely selective for cancer cells. Therefore, these drugs can also significantly affect healthy cells. Prodrug therapy provides an alternative approach using a less cytotoxic form of anticancer drug. It involves the synthesis of inactive drug derivatives which are converted to an active form inside the body and, preferably, only at the site of cancerous tissues, thereby reducing adverse drug reaction (ADR) events. Herein, we demonstrate a prodrug activation strategy by utilizing the reaction between aryl azide and endogenous acrolein. Since acrolein is generally overproduced by most cancer cells, we anticipate our strategy as a starting point for further applications in mouse models with various cancers. Furthermore, cancer drugs that have had therapeutic index challenges might be reconsidered for application by utilizing our strategy.