Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Front Immunol ; 15: 1400744, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799446

RESUMO

Hepatocellular carcinoma (HCC) is a significant contributor to cancer-related deaths in the world. The development and progression of HCC are closely correlated with the abnormal regulation of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Important biological pathways in cancer biology, such as cell proliferation, death, and metastasis, are impacted by these ncRNAs, which modulate gene expression. The abnormal expression of non-coding RNAs in HCC raises the possibility that they could be applied as new biomarkers for diagnosis, prognosis, and treatment targets. Furthermore, by controlling the expression of cancer-related genes, miRNAs can function as either tumor suppressors or oncogenes. On the other hand, lncRNAs play a role in the advancement of cancer by interacting with other molecules within the cell, which, in turn, affects processes such as chromatin remodeling, transcription, and post-transcriptional processes. The importance of ncRNA-driven regulatory systems in HCC is being highlighted by current research, which sheds light on tumor behavior and therapy response. This research highlights the great potential of ncRNAs to improve patient outcomes in this difficult disease landscape by augmenting the present methods of HCC care through the use of precision medicine approaches.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/diagnóstico , Prognóstico , Biomarcadores Tumorais/genética , RNA não Traduzido/genética , RNA Longo não Codificante/genética , Animais , MicroRNAs/genética
2.
Phytomedicine ; 123: 155175, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951150

RESUMO

BACKGROUND: Sepsis-related cardiac dysfunction is believed to be a primary cause of high morbidity and mortality. Metabolic reprogramming is closely linked to NLRP3 inflammasome activation and dysregulated glycolysis in activated macrophages, leading to inflammatory responses in septic cardiomyopathy. Succinate dehydrogenase (SDH) and succinate play critical roles in the progression of metabolic reprogramming in macrophages. Inhibition of SDH may be postulated as an effective strategy to attenuate macrophage activation and sepsis-induced cardiac injury. PURPOSE: This investigation was designed to examine the role of potential compounds that target SDH in septic cardiomyopathy and the underlying mechanisms involved. METHODS/RESULTS: From a small molecule pool containing about 179 phenolic compounds, we found that chicoric acid (CA) had the strongest ability to inhibit SDH activity in macrophages. Lipopolysaccharide (LPS) exposure stimulated SDH activity, succinate accumulation and superoxide anion production, promoted mitochondrial dysfunction, and induced the expression of hypoxia-inducible factor-1α (HIF-1α) in macrophages, while CA ameliorated these changes. CA pretreatment reduced glycolysis by elevating the NAD+/NADH ratio in activated macrophages. In addition, CA promoted the dissociation of K(lysine) acetyltransferase 2A (KAT2A) from α-tubulin, and thus reducing α-tubulin acetylation, a critical event in the assembly and activation of NLRP3 inflammasome. Overexpression of KAT2A neutralized the effects of CA, indicating that CA inactivated NLRP3 inflammasome in a specific manner that depended on KAT2A inhibition. Importantly, CA protected the heart against endotoxin insult and improved sepsis-induced cardiac mitochondrial structure and function disruption. Collectively, CA downregulated HIF-1α expression via SDH inactivation and glycolysis downregulation in macrophages, leading to NLRP3 inflammasome inactivation and the improvement of sepsis-induced myocardial injury. CONCLUSION: These results highlight the therapeutic role of CA in the resolution of sepsis-induced cardiac inflammation.


Assuntos
Ácidos Cafeicos , Cardiomiopatias , Sepse , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Tubulina (Proteína)/metabolismo , Reprogramação Metabólica , Macrófagos/metabolismo , Succinatos/efeitos adversos , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Sepse/complicações , Sepse/tratamento farmacológico , Ácido Succínico/efeitos adversos , Lipopolissacarídeos/efeitos adversos
3.
Metabolism ; 145: 155579, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37127227

RESUMO

BACKGROUND: Na+/K+-ATPase (NKA), an ion pumping enzyme ubiquitously expressed in various cells, is critically involved in cellular ion homeostasis and signal transduction. However, the role of NKA in hepatic lipid homeostasis has yet to be fully characterized. METHODS: The activity of NKA and NKAα1 expression were determined in steatotic cells, mice and patients. The roles of NKAα1 in hepatosteatosis were detected using hepatocyte knockout or specific overexpression of NKAα1 in mice. RESULTS: Herein, we demonstrated that the expression and activity of α1 subunit of NKA (NKAα1) were lowered in the livers of nonalcoholic fatty liver disease (NAFLD) patients, high-fat diet (HFD)-induced obese mice, and genetically obese (ob/ob, db/db) mice, as well as oleic acid-induced hepatocytes. Hepatic deficiency of NKAα1 exacerbated, while adeno-associated virus-mediated liver specific overexpression of NKAα1 alleviated hepatic steatosis through regulation of fatty acid oxidation (FAO) and lipogenesis. Mechanistically, we revealed that NKAα1 upregulated sirtuin 1 (SIRT1) via interacting with ubiquitin specific peptidase 22 (USP22), a deubiquitinating enzyme for the stabilization and deubiquitination of SIRT1, thus activating the downstream autophagy signaling. Blockade of the SIRT1/autophagy signaling pathway eliminated the protective effects of NKAα1 against lipid deposition in hepatocytes. Importantly, we found that an antibody against the DR region (897DVEDSYGQQWTYEQR911) of NKAα1 subunit (DR-Ab) ameliorated hepatic steatosis through maintaining the membrane density of NKAα1 and inducing its activation. CONCLUSIONS: Collectively, this study renews the functions of NKAα1 in liver lipid metabolism and provides a new clue for gene therapy or antibody treatment of hepatic lipid metabolism disturbance by targeting NKAα1.


Assuntos
Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Camundongos Obesos , Sirtuína 1/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatócitos/metabolismo , Ácido Oleico/metabolismo , Ácido Oleico/farmacologia , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL
4.
Chem Sci ; 14(16): 4390-4396, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37123189

RESUMO

The arylation of sterically hindered amines represents one of the long-standing challenges in synthetic chemistry. Herein, we report a highly efficient Ni-catalysed arylation of sterically hindered primary and secondary amines with aryl chlorides or phenol derivatives enabled by an unsymmetric N-heterocyclic carbene (NHC) ligand. The protocol provides general, efficient, and scalable access to various sterically demanding anilines in excellent yields under mild conditions. A wide range of functional groups and heterocycles are compatible (>50 examples), including those present in biologically relevant molecules. Computational studies suggest that the unsymmetric bulky and flexible NHC ligand was critical to balance the oxidative addition and reductive elimination elementary steps, thus promoting this challenging transformation.

5.
J Adv Res ; 51: 161-179, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36334887

RESUMO

INTRODUCTION: Meteorin-like hormone (Metrnl) is ubiquitously expressed in skeletal muscle, heart, and adipose with beneficial roles in obesity, insulin resistance, and inflammation. Metrnl is found to protect against cardiac hypertrophy and doxorubicin-induced cardiotoxicity. However, its role in diabetic cardiomyopathy (DCM) is undefined. OBJECTIVES: We aimed to elucidate the potential roles of Metrnl in DCM. METHODS: Gain- andloss-of-function experimentswere utilized to determine the roles of Metrnl in the pathological processes of DCM. RESULTS: We found that plasma Metrnl levels, myocardial Metrnl protein and mRNA expressions were significantly downregulated in both streptozotocin (STZ)-induced (T1D) mice and leptin receptor deficiency (db/db) (T2D) mice. Cardiac-specific overexpression (OE) of Metrnl markedly ameliorated cardiac injury and dysfunction in both T1D and T2D mice. In sharp contrast, specific deletion of Metrnl in the heart had the opposite phenotypes. In parallel, Metrnl OE ameliorated, whereas Metrnl downregulation exacerbated high glucose (HG)-elicited hypertrophy, apoptosis and oxidative damage in primary neonatal rat cardiomyocytes. Antibody-induced blockade of Metrnl eliminated the effects of benefits of Metrnl in vitro and in vivo. Mechanistically, Metrnl activated the autophagy pathway and inhibited the cGAS/STING signaling in a LKB1/AMPK/ULK1-dependent mechanism in cardiomyocytes. Besides, Metrnl-induced ULK1 phosphorylation facilitated the dephosphorylation and mitochondrial translocation of STING where it interacted with tumor necrosis factor receptor-associated factor 2 (TRAF2), a scaffold protein and E3 ubiquitin ligase that was responsible for ubiquitination and degradation of STING, rendering cardiomyocytes sensitive to autophagy activation. CONCLUSION: Thus, Metrnl may be an attractive therapeutic target or regimen for treating DCM.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Animais , Camundongos , Ratos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/farmacologia , Autofagia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Miócitos Cardíacos , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/farmacologia
6.
Front Physiol ; 13: 848867, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35530510

RESUMO

Growing evidence suggests that hypertension is one of the leading causes of cardiovascular morbidity and mortality since uncontrolled high blood pressure increases the risk of myocardial infarction, aortic dissection, hemorrhagic stroke, and chronic kidney disease. Impaired vascular homeostasis plays a critical role in the development of hypertension-induced vascular remodeling. Abnormal behaviors of vascular cells are not only a pathological hallmark of hypertensive vascular remodeling, but also an important pathological basis for maintaining reduced vascular compliance in hypertension. Targeting vascular remodeling represents a novel therapeutic approach in hypertension and its cardiovascular complications. Phytochemicals are emerging as candidates with therapeutic effects on numerous pathologies, including hypertension. An increasing number of studies have found that curcumin, a polyphenolic compound derived from dietary spice turmeric, holds a broad spectrum of pharmacological actions, such as antiplatelet, anticancer, anti-inflammatory, antioxidant, and antiangiogenic effects. Curcumin has been shown to prevent or treat vascular remodeling in hypertensive rodents by modulating various signaling pathways. In the present review, we attempt to focus on the current findings and molecular mechanisms of curcumin in the treatment of hypertensive vascular remodeling. In particular, adverse and inconsistent effects of curcumin, as well as some favorable pharmacokinetics or pharmacodynamics profiles in arterial hypertension will be discussed. Moreover, the recent progress in the preparation of nano-curcumins and their therapeutic potential in hypertension will be briefly recapped. The future research directions and challenges of curcumin in hypertension-related vascular remodeling are also proposed. It is foreseeable that curcumin is likely to be a therapeutic agent for hypertension and vascular remodeling going forwards.

7.
Angew Chem Int Ed Engl ; 60(29): 16077-16084, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-33901337

RESUMO

The transition-metal-catalyzed C-N cross-coupling has revolutionized the construction of amines. Despite the innovations of multiple generations of ligands to modulate the reactivity of the metal center, ligands for the low-temperature enantioselective amination of aryl halides remain a coveted target of catalyst engineering. Designs that promote one elementary reaction often create bottlenecks at other steps. We here report an unprecedented low-temperature (as low as -50 °C), enantioselective Ni-catalyzed C-N cross-coupling of aryl chlorides with sterically hindered secondary amines via a kinetic resolution process (s factor up to >300). A bulky yet flexible chiral N-heterocyclic carbene (NHC) ligand is leveraged to drive both oxidative addition and reductive elimination with low barriers and control the enantioselectivity. Computational studies indicate that the rotations of multiple σ-bonds on the C2 -symmetric chiral ligand adapt to the changing needs of catalytic processes. We expect this design would be widely applicable to diverse transition states to achieve other challenging metal-catalyzed asymmetric cross-coupling reactions.

8.
Int J Biol Macromol ; 124: 1156-1166, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30521893

RESUMO

The effectiveness of pectin coatings enriched with clove essential oil (CEO), as new edible coatings were investigated to preserve bream (Megalobrama ambycephala) fillets during refrigeration over a period of 15 days. All samples were analyzed for physicochemical (pH, PV, TBA and TVB-N), microbiological (Total viable count, Psychrophilic bacteria, Lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp., H2S producing bacteria) and organoleptic attributes. The results revealed that the CEO incorporation reduced the extent of lipid oxidation, as judged by PV, TBA and TVB-N, thus extending the shelf life of bream fillets by at least 15 days. Moreover, the application of pectin coatings with CEO improved the weight loss, water holding capacity, textural and color attributes of the bream samples significantly compared to untreated sample. Pectin coating along with CEO was effective in inhibiting bacterial growth especially in gram-negative bacteria, while the growth of lactic acid bacteria remained constant for most of the storage period. The effect on the microorganisms during storage was in accordance with biochemical indexes of the quality, representing the viability of these coatings for bream preservation. Thus, the coatings developed in present study could inhibit the development of lipid oxidation during cold storage, representing an option as a seafood preservative.


Assuntos
Óleo de Cravo/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Cyprinidae , Conservação de Alimentos/métodos , Pectinas/farmacologia , Alimentos Marinhos/análise , Animais , Óleo de Cravo/química , Materiais Revestidos Biocompatíveis/química , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Embalagem de Alimentos/métodos , Armazenamento de Alimentos , Sulfeto de Hidrogênio/química , Concentração de Íons de Hidrogênio , Lactobacillales/classificação , Lactobacillales/efeitos dos fármacos , Lactobacillales/isolamento & purificação , Peroxidação de Lipídeos/efeitos dos fármacos , Odorantes/análise , Pectinas/química , Pseudomonas/classificação , Pseudomonas/efeitos dos fármacos , Pseudomonas/isolamento & purificação , Refrigeração/métodos , Paladar/fisiologia
9.
Int J Biol Macromol ; 106: 670-680, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28818729

RESUMO

The increasing demand for bio-based materials to be used in food packaging has stimulated the development of novel, environmentally-friendly edible films. Antimicrobial films were developed by incorporating different levels of clove bud essential oil (0.5%, 1.0%, and 1.5%) into the citrus pectin in order to modify the functional properties of the films. Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry analysis (DSC) and X-ray diffraction (XRD) were performed, together with the determination of physical, optical, mechanical, antioxidant and antimicrobial properties of pectin emulsified films. The inclusion of oil significantly enhanced the water barrier properties of the films. Addition of oil leads to more opaque films with relatively heterogeneous microstructure, resulting in an increase in film opacity. The composite films were more resistant to breakage and more flexible than the control films. Differential scanning calorimetry (DSC) demonstrated that films incorporating CEO exhibited improved heat stability with slightly higher degradation temperature, compared with control films. The inhibitory effect of pectin films with CEO was also evaluated on three common foodborne bacteria. These results revealed that clove oil has a good potential to be incorporated into citrus pectin to make antimicrobial edible films or coatings for various food applications.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Óleo de Cravo/química , Embalagem de Alimentos/métodos , Membranas Artificiais , Pectinas/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Óleo de Cravo/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Módulo de Elasticidade , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Pectinas/farmacologia , Permeabilidade , Picratos/antagonistas & inibidores , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Vapor/análise , Syzygium/química , Resistência à Tração
10.
Mol Plant Pathol ; 11(2): 203-12, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20447270

RESUMO

A 3'-terminal, 77-nucleotide sequence of Bamboo mosaic virus (BaMV) minus-strand RNA (Ba-77), comprising a 5' stem-loop, a spacer and a 3'-CUUUU sequence, can be used to initiate plus-strand RNA synthesis in vitro. To understand the mechanism of plus-strand RNA synthesis, mutations were introduced in the 5' untranslated region of BaMV RNA, resulting in changes at the 3' end of minus-strand RNA. The results showed that at least three uridylate residues in 3'-CUUUU are required and the changes at the penultimate U are deleterious to viral accumulation in Nicotiana benthamiana protoplasts. Results from UV-crosslinking and in vitro RNA-dependent RNA polymerase competition assays suggested that the replicase preferentially interacts with the stem structure of Ba-77. Finally, CMV/83 + UUUUC, a heterologus RNA, which possesses about 80 nucleotides containing the 3'-CUUUU pentamer terminus, and which folds into a secondary structure similar to that of Ba-77, could be used as template for RNA production by the BaMV replicase complex in vitro.


Assuntos
Bambusa/virologia , Vírus do Mosaico/enzimologia , Vírus do Mosaico/genética , RNA Viral/biossíntese , RNA Viral/química , RNA Polimerase Dependente de RNA/metabolismo , Nucleotídeos de Adenina/metabolismo , Bambusa/efeitos dos fármacos , Bambusa/efeitos da radiação , Sequência de Bases , Reagentes de Ligações Cruzadas/farmacologia , Genoma Viral/genética , Dados de Sequência Molecular , Vírus do Mosaico/efeitos dos fármacos , Vírus do Mosaico/efeitos da radiação , Mutação/genética , Conformação de Ácido Nucleico , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/efeitos da radiação , Folhas de Planta/virologia , Regiões Promotoras Genéticas/genética , Estrutura Terciária de Proteína , Protoplastos/efeitos dos fármacos , Protoplastos/metabolismo , Protoplastos/efeitos da radiação , Protoplastos/virologia , RNA Viral/genética , RNA Polimerase Dependente de RNA/química , Moldes Genéticos , Nicotiana/efeitos dos fármacos , Nicotiana/efeitos da radiação , Nicotiana/virologia , Raios Ultravioleta , Uridina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA