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1.
Cell ; 146(6): 1016-28, 2011 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21925322

RESUMO

We report the identification of 67 previously undescribed histone modifications, increasing the current number of known histone marks by about 70%. We further investigated one of the marks, lysine crotonylation (Kcr), confirming that it represents an evolutionarily-conserved histone posttranslational modification. The unique structure and genomic localization of histone Kcr suggest that it is mechanistically and functionally different from histone lysine acetylation (Kac). Specifically, in both human somatic and mouse male germ cell genomes, histone Kcr marks either active promoters or potential enhancers. In male germinal cells immediately following meiosis, Kcr is enriched on sex chromosomes and specifically marks testis-specific genes, including a significant proportion of X-linked genes that escape sex chromosome inactivation in haploid cells. These results therefore dramatically extend the repertoire of histone PTM sites and designate Kcr as a specific mark of active sex chromosome-linked genes in postmeiotic male germ cells.


Assuntos
Regulação da Expressão Gênica , Código das Histonas , Animais , Células HeLa , Histonas/química , Histonas/metabolismo , Humanos , Lisina/metabolismo , Masculino , Meiose , Camundongos , Processamento de Proteína Pós-Traducional , Testículo/citologia , Testículo/metabolismo
2.
Circ Res ; 132(6): 707-722, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36786193

RESUMO

BACKGROUND: Cardiac remodeling in heart failure involves macrophage-mediated immune responses. Recent studies have shown that a PRR (pattern recognition receptor) called dectin-1, expressed on macrophages, mediates proinflammatory responses. Whether dectin-1 plays a role in pathological cardiac remodeling is unknown. Here, we identified a potential role of dectin-1 in this disease. METHODS: To model aberrant cardiac remodeling, we utilized mouse models of chronic Ang II (angiotensin II) infusion. In this model, we assessed the potential role of dectin-1 through using D1KO (dectin-1 knockout) mice and bone marrow transplantation chimeric mice. We then used cellular and molecular assays to discover the underlying mechanisms of dectin-1 function. RESULTS: We found that macrophage dectin-1 is elevated in mouse heart tissues following chronic Ang II administration. D1KO mice were significantly protected against Ang II-induced cardiac dysfunction, hypertrophy, fibrosis, inflammatory responses, and macrophage infiltration. Further bone marrow transplantation studies showed that dectin-1 deficiency in bone marrow-derived cells prevented Ang II-induced cardiac inflammation and dysfunction. Through detailed molecular studies, we show that Ang II binds directly to dectin-1, causing dectin-1 homodimerization and activating the downstream Syk (spleen tyrosine kinase)/NF-κB (nuclear factor kappa B) signaling pathway to induce expression of inflammatory and chemoattractant factors. Mutagenesis studies identified R184 in the C-type lectin domain to interact with Ang II. Blocking dectin-1 in macrophages suppresses Ang II-induced inflammatory mediators and subsequent intercellular cross talk with cardiomyocytes and fibroblasts. CONCLUSIONS: Our study has discovered dectin-1 as a new nonclassical receptor of Ang II and a key player in cardiac remolding and dysfunction. These studies suggest that dectin-1 may be a new target for treating hypertension-related heart failure.


Assuntos
Insuficiência Cardíaca , Hipertensão , Camundongos , Animais , Remodelação Ventricular/fisiologia , Lectinas Tipo C/genética , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Angiotensina II/toxicidade , Camundongos Knockout , Fibrose , Camundongos Endogâmicos C57BL
3.
Apoptosis ; 29(5-6): 693-708, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38296888

RESUMO

The role of disulfidptosis in kidney renal clear cell carcinoma (KIRC) remains unknown. This study investigated disulfidptosis-related biomarkers for KIRC prognosis prediction and individualized treatment. KIRC patients were clustered by disulfidptosis profiles. Differential expression analysis, survival models, and machine learning were used to construct the disulfidptosis-related prognostic signature (DRPS). Characterizations of the tumor immune microenvironment, genetic drivers, drug sensitivity, and immunotherapy response were explored according to the DRPS risk stratification. Markers included in the signature were validated using single-cell, spatial transcriptomics, quantitative RT-qPCR, and immunohistochemistry. In the discovery cohort, we unveiled two clusters of KIRC patients that differed significantly in disulfidptosis regulator expressions and overall survival (OS). After multiple feature selection steps, a DRPS prognostic model with four features (CHAC1, COL7A1, FOXM1, SHOX2) was constructed and validated. Combined with clinical factors, the model demonstrated robust performance in the discovery and external validation cohorts (5-year AUC = 0.793 and 0.846, respectively). KIRC patients with high-risk scores are characterized by inferior OS, less tumor purity, and increased infiltrations of fibroblasts, M1 macrophages, and B cells. High-risk patients also have higher frequencies of BAP1 and AHNAK2 mutation. Besides, the correlation between the DRPS score and the chemotherapy-response signature indicated the potential effect of Gefitinib for high-risk patients. Among the signature genes, FOXM1 is highly expressed in cycling tumor cells and exhibits spatial aggregation, while others are expressed sparsely within tumor samples. The DRPS model enables improved clinical management and personalized KIRC therapy. The identified biomarkers and immune characteristics offer new mechanistic insight into disulfidptosis in KIRC.


Assuntos
Biomarcadores Tumorais , Carcinoma de Células Renais , Neoplasias Renais , Medicina de Precisão , Humanos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Prognóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Microambiente Tumoral/genética , Regulação Neoplásica da Expressão Gênica , Masculino , Feminino , Transcriptoma
4.
Anal Chem ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39149969

RESUMO

The distribution of small biomolecules, particularly amino acids (AAs), differs between normal cells and cancer cells. Imaging this distribution is crucial for gaining a deeper understanding of their physiological and pathological significance. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) provides accurate in situ visualization information. However, the analysis of AAs remains challenging due to the background interference by conventional MALDI matrices. On tissue chemical derivatization (OTCD) MSI serves as an important approach to resolve this issue. We designed, synthesized, and tested a series of pyridinium salt probes and screened out the 1-(4-(((2,5-dioxopyrrolidin-1-yl)oxy)carbonyl)phenyl)-2,4,6-triphenylpyridin-1-ium (DCT) probe with the highest reaction efficiency and the most effective detection. Moreover, a quantum chemistry calculation was executed to address mechanistic insight into the chemical nature of the novel probes. DCT was found to map 20 common AAs in normal mouse tissues for the first time, which allowed differentiation of AA distribution in normal, normal interstitium, tumor, and tumor interstitium regions and provided potential mechanistic insights for cancer research and other biomedical studies.

5.
Chemistry ; 30(36): e202401171, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38646836

RESUMO

Stimuli-responsive crystalline materials have received much attention for being potential candidates of smart materials. However, the occurrence of polymorphism-driven stimuli responses in crystalline materials remains interesting but rare. Herein, three polymorphs of an acylhydrazone derivative, N'-[(E)-(1-benzofuran-2-yl) methylidene] pyridine -4-carbohydrazide (BFMP) were prepared. Form-1 undergoes a photomechanical response via E→Z photoisomerization under UV irradiation, accompanied by a decrease in fluorescence intensity and a change from colorless to yellow. Two types of Z→E thermal isomerization mechanisms with significant differences in conversion rate were observed at different temperatures in form-1. The solid-melt-solid transition has a faster conversion rate compared to the solid-solid transition due to freedom from lattice confinement. The transition from form-2 to form-3 can be achieved under grinding, coupled with a significant decrease in fluorescence intensity. The similar molecular stacking pattern of form-2 and form-3 provides a structural basis for the grinding-induced crystalline transition behavior. In addition, the presence of the pyridine moiety imparts an acidochromic property. The combination of photochromism and acidochromism explores the possible applications of acylhydrazone derivatives in information encryption.

6.
Cerebellum ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39222195

RESUMO

Spontaneous cerebellar hemorrhage (SCH) patients have a low success rate in extubation, but there are currently no guidelines establishing specifically for SCH patients extubation. The study included 68 SCH patients who received mechanical ventilation for more than 24 h, with 39 cases (57.3%) resulting in successful extubation. The multivariate analysis identified four factors significantly associated with extubation success: patient age under 66 years, an Intracerebral Hemorrhage (ICH) score less than 4 points, the presence of tissue shift, and a Glasgow Coma Scale (GCS) score (excluding language) above 6 points at extubation. By simplifying the prediction model, we obtained the Spontaneous Cerebellar Hemorrhage Extubation Success scoring system (SCHES-SCORE). Within the scoring system, 2 points were allocated for a GCS score (excluding language) above 6 at extubation, 1 point each for age under 66 years and an ICH score below 4, while tissue shift was assigned a negative point. A score of Grade A (SCHES-SCORE = 3-4) was found to correlate with a 92.9% success rate for extubation. The area under the receiver operating characteristic curve was 0.923 (95% CI, 0.863 to 0.983). Notably, successful extubation was significantly linked to reduced durations of mechanical ventilation, intensive care unit (ICU) stay, and total hospital stay. In conclusion, the scoring system developed for assessing extubation outcomes in SCH patients has the potential to enhance the rate of successful extubation and overall patient outcomes.

7.
Am J Med Genet A ; 194(5): e63504, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38153133

RESUMO

Congenital cataracts are the leading cause of irreversible visual disability in children, and genetic factors play an important role in their development. In this study, targeted exome sequencing revealed a novel single-base deletional mutation of MIP (c.301delG; p.Ala101Profs*16) segregated with congenital punctate cataract in a Chinese family. The hydrophobic properties, and secondary and tertiary structures for truncated MIP were predicted to affect the function of protein by bioinformatics analysis. When MIP-WT and MIP-Ala101fs expression constructs were singly transfected into HeLa cells, it was found that the mRNA level showed no significant difference, while the protein level of the mutant was remarkably reduced compared to that of the wild-type MIP. Immunofluorescence images showed that the MIP-WT was principally localized to the plasma membrane, whereas the MIP-Ala101fs protein was aberrantly trapped in the cytoplasm. Furthermore, the cell-to-cell adhesion capability and the cell-to-cell communication property were both significantly reduced for MIP-Ala101fs compared to the MIP-WT (all *p < 0.05). This is the first report of the c.301delG mutation in the MIP gene associated with autosomal dominant congenital cataracts. We propose that the cataract is caused by the decreased protein expression and reduced cell-to-cell adhesion by the mutant MIP. The impaired trafficking or instability of the mutant protein, as well as compromised intercellular communication is probably a concurrent result of the mutation. The results expand the genetic and phenotypic spectra of MIP and help to better understand the molecular basis of congenital cataracts.


Assuntos
Catarata , Proteínas do Olho , Criança , Humanos , Catarata/genética , Catarata/congênito , Adesão Celular/genética , China , Proteínas do Olho/genética , Células HeLa , Mutação
8.
Bioorg Chem ; 151: 107630, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39059073

RESUMO

Seven new 13,14-seco withaphysalins including two new skeletons (1 and 9) were isolated from the whole plants of Physalis minima, together with three known analogues (6-8). Among them, compound 1 was an extremely rare steroid with a 6, 8-cyclo ring. Their structures were established by extensive analysis of spectroscopic data, experimental electronic circular dichroism measurements, and single-crystal X-ray crystallographic analysis. In Raw264.7 cells, compounds 1-3, 5, 6, and 8 demonstrated potent ability to reduce the NLRP3-dependent caspase-1 activation. Among these compounds, 1 and 2 showed a superior potential, consistently concentration-dependent downregulating NLRP3-dependent proinflammatory cytokine IL-1ß production in macrophage. Mechanistically, compounds 1 and 2 reduced the cleavage of caspase-1 and GSDMD, and exhibited no obvious impact both on the NF-κB activation and the expression of NLRP3 and IL-1ß, suggesting that the compounds target the activation of the NLRP3 pathway mainly by inhibiting the NLRP3 inflammasome activation step rather than the priming step.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Physalis , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Camundongos , Animais , Physalis/química , Inflamassomos/metabolismo , Inflamassomos/antagonistas & inibidores , Células RAW 264.7 , Estrutura Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Interleucina-1beta/metabolismo , Interleucina-1beta/antagonistas & inibidores
9.
Cell Mol Life Sci ; 80(7): 184, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340199

RESUMO

Macrophage activation has been shown to play an essential role in renal fibrosis and dysfunction in hypertensive chronic kidney disease. Dectin-1 is a pattern recognition receptor that is also involved in chronic noninfectious diseases through immune activation. However, the role of Dectin-1 in Ang II-induced renal failure is still unknown. In this study, we found that Dectin-1 expression on CD68 + macrophages was significantly elevated in the kidney after Ang II infusion. We assessed the effect of Dectin-1 on hypertensive renal injury using Dectin-1-deficient mice infused by Angiotensin II (Ang II) at 1000 ng/kg/min for 4 weeks. Ang II-induced renal dysfunction, interstitial fibrosis, and immune activation were significantly attenuated in Dectin-1-deficient mice. A Dectin-1 neutralizing antibody and Syk inhibitor (R406) were used to examine the effect and mechanism of Dectin-1/Syk signaling axle on cytokine secretion and renal fibrosis in culturing cells. Blocking Dectin-1 or inhibiting Syk significantly reduced the expression and secretion of chemokines in RAW264.7 macrophages. The in vitro data showed that the increase in TGF-ß1 in macrophages enhanced the binding of P65 and its target promotor via the Ang II-induced Dectin-1/Syk pathway. Secreted TGF-ß1 caused renal fibrosis in kidney cells through Smad3 activation. Thus, macrophage Dectin-1 may be involved in the activation of neutrophil migration and TGF-ß1 secretion, thereby promoting kidney fibrosis and dysfunction.


Assuntos
Angiotensina II , Hipertensão Renal , Camundongos , Animais , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Neutrófilos/metabolismo , Rim/metabolismo , Hipertensão Renal/metabolismo , Hipertensão Renal/patologia , Macrófagos/metabolismo , Fibrose
10.
Gynecol Endocrinol ; 40(1): 2405098, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39297784

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder in premenopausal women, often linked to abdominal obesity, insulin resistance, and metabolic issues. With its heterogeneous nature, PCOS treatment should be tailored to individual symptoms and patient preferences. This study examines collaboration networks among countries, institutions, authors, references, and journals related to PCOS treatment. METHODS: Web of Science data was analyzed using VOSviewer and CiteSpace for bibliometric visualization. Chinese and Western medicine treatments for PCOS were reviewed, emphasizing symptom-targeted solutions. RESULTS: Data from 4682 records authored by 400 individuals from 515 institutes in 62 countries revealed China as the leading contributor. Notable authors include Monash University and Richard S. Legro. Common research themes include adipocytes, inflammation, insulin sensitivity, oxidative stress, and the gut microbiome. Tailoring treatment to individual needs is essential, focusing on hyperandrogenism, ovulation, and insulin resistance, with lifestyle counseling to address obesity. CONCLUSION: This bibliometric analysis provides valuable insights into the research status of PCOS treatment. China has made significant contributions, and complementary and alternative therapies, such as traditional Chinese medicine and acupuncture, have also shown beneficial effects recently. The research on inflammation, oxidative stress, and the gut microbiome may provide new targets and strategies for the treatment of PCOS. The recognition of the metabolic problems in PCOS patients facilitates the formulation of more personalized treatment plans to improve the prognosis of patients.


Assuntos
Bibliometria , Síndrome do Ovário Policístico , Síndrome do Ovário Policístico/terapia , Humanos , Feminino , Resistência à Insulina
11.
Clin Exp Ophthalmol ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39135375

RESUMO

BACKGROUND: To compare pain perception, pupil behaviours, and cytokine levels during first-eye and second-eye femtosecond laser-assisted cataract surgery (FLACS) and determine which is better regarding a short or long interval for bilateral FLACS. METHODS: Notably, 96 eyes of 48 patients with bilateral cataracts underwent the first surgeries in the left or right eye, according to a random sequence. They were further randomised into 2- and 6-week subgroups based on surgery intervals. Pupil size was measured from captured images, and pain perception was assessed using a visual analog scale (VAS). Aqueous humour prostaglandin E2 (PGE2), monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-6, and IL-8 levels were also quantitatively analysed. All patients were followed for 1 week to evaluate changes in endothelial cell density (ECD), central corneal thickness (CCT), and macular central subfield thickness (CST). RESULTS: Ocular pain was significantly higher in patients who underwent second-eye FLACS. First tear break-up time was negatively correlated with VAS score. MCP-1 levels were significantly higher in patients who underwent second-eye FLACS, and VAS scores were positively correlated with MCP-1 levels across all patients. There were no differences between sequential FLACS in miosis, PGE2, IL-6, IL-8 levels and changes in postoperative ECD, CCT, and CST. Patients who underwent second-eye FLACS after 6 weeks showed more CCT, CST, and MCP-1 changes than baseline. CONCLUSION: Second-eye FLACS causes more pain and upregulated MCP-1. There was no difference between sequential FLACS in PGE2 levels, miosis, and postoperative inflammation. Furthermore, first-eye FLACS triggered a sympathetic irritation, particularly after a 6-week interval.

12.
Molecules ; 29(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39064899

RESUMO

Nickel-based catalysts are regarded as the most excellent urea oxidation reaction (UOR) catalysts in alkaline media. Whatever kind of nickel-based catalysts is utilized to catalyze UOR, it is widely believed that the in situ-formed Ni3+ moieties are the true active sites and the as-utilized nickel-based catalysts just serve as pre-catalysts. Digging the pre-catalyst effect on the activity of Ni3+ moieties helps to better design nickel-based catalysts. Herein, five different anions of OH-, CO32-, SiO32-, MoO42-, and WO42- were used to bond with Ni2+ to fabricate the pre-catalysts ß-Ni(OH)2, Ni-CO3, Ni-SiO3, Ni-MoO4, and Ni-WO4. It is found that the true active sites of the five as-fabricated catalysts are the same in situ-formed Ni3+ moieties and the five as-fabricated catalysts demonstrate different UOR activity. Although the as-synthesized five catalysts just serve as the pre-catalysts, they determine the quantity of active sites and activity per active site, thus determining the catalytic activity of the catalysts. Among the five catalysts, the amorphous nickel tungstate exhibits the most superior activity per active site and can catalyze UOR to reach 158.10 mA·cm-2 at 1.6 V, exceeding the majority of catalysts. This work makes for a deeper understanding of the pre-catalyst effect on UOR activity and helps to better design nickel-based UOR catalysts.

13.
Int J Cosmet Sci ; 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433250

RESUMO

OBJECTIVE: Erythema, characterized by the redness of the skin, is a common skin reaction triggered by various endogenous and exogenous factors. This response is often a result of the activation of underlying inflammatory mechanisms within the skin. The objective of this study is to investigate the potential benefits of applying a combination of skincare ingredients, namely allantoin, bisabolol, D-panthenol and dipotassium glycyrrhizinate (AB5D), in the modulation of inflammatory factors associated with erythema. Additionally, the study aims to elucidate the mechanisms by which these ingredients exert their combined actions to alleviate erythema-associated inflammation. METHODS: Human epidermal keratinocytes were exposed to UVB and subsequently treated with AB5D. Transcriptomics profiling was performed to analyse the dose-response effect of AB5D treatment on keratinocytes. The quantitation of inflammatory mediators, including PGE2 , IL-1α, IL-6, IL-8, IL-1RA and TNFα, was performed on cultured media. Additionally, the oxygen radical absorbance capacity (ORAC) assay was carried out to evaluate the total antioxidant capacity of both individual ingredients and the AB5D combination. To assess the in-vitro antioxidant effects of AB5D against UVB-induced oxidative stress in hTERT keratinocytes, real-time quantitation of mitochondrial superoxide was measured through live-cell imaging. RESULTS: The application of AB5D to UVB-exposed keratinocytes downregulated gene sets associated with inflammatory responses, highlighting the anti-inflammatory properties of AB5D. Specifically, AB5D effectively reduced the production of PGE2 , leading to the downregulation of inflammatory cytokines. Moreover, our findings indicate that AB5D exhibits antioxidative capabilities, functioning as both an antioxidant agent and a regulator of antioxidant enzyme expression to counteract the detrimental effects of cellular oxidative stress. CONCLUSION: We demonstrated that AB5D can reduce UVB-induced PGE2 , IL-1α, IL-6, IL-8, IL-1RA and TNFα as well as mitochondrial superoxide. These findings suggest that AB5D may alleviate erythema by modulating inflammation via PGE2 and through antioxidation mechanisms.


L'érythème, caractérisé par une rougeur sur la peau, est une réaction cutanée fréquente déclenchée par divers facteurs endogènes et exogènes. Il s'agit d'une réponse qui résulte souvent de l'activation des mécanismes inflammatoires sous-jacents dans la peau. OBJECTIF: cette étude vise à étudier les bénéfices potentiels de l'application d'une association d'ingrédients de soins cutanés, à savoir l'allantoïne, le bisabolol, le D-panthénol et le glycyrrhizinate dipotassique (AB5D) dans la modulation des facteurs inflammatoires associés à l'érythème. En outre, l'étude vise à élucider les mécanismes par lesquels ces ingrédients exercent leurs actions combinées pour soulager l'inflammation associée à l'érythème. MÉTHODES: les kératinocytes épidermiques humains ont été exposés aux UVB et traités par la suite par AB5D. Un profilage transcriptomique a été effectué pour analyser l'effet dose-réponse du traitement par AB5D sur les kératinocytes. La quantification des médiateurs inflammatoires, y compris PGE2, IL-1α, IL-6, IL-8, IL-1RA et TNFα, a été effectuée sur des milieux de culture. En outre, le dosage de la capacité d'absorption des radicaux oxygénés (Oxygen Radical Absorbance Capacity, ORAC) a été effectué pour évaluer la capacité antioxydante totale des deux ingrédients individuels et de l'association AB5D. Pour évaluer les effets antioxydants in vitro de l'AB5D contre le stress oxydatif induit par les UVB dans les kératinocytes hTERT, on a mesuré la quantification en temps réel du superoxyde mitochondrial par des tests d'imagerie des cellules vivantes. RÉSULTATS: l'application de l'AB5D aux ensembles de gènes régulés à la baisse exposés aux kératinocytes UVB associés à des réponses inflammatoires, a mis en évidence les propriétés anti-inflammatoires de l'AB5D. Plus précisément, l'AB5D a efficacement réduit la production de PGE2, entraînant une régulation négative des cytokines inflammatoires. En outre, nos résultats indiquent que l'AB5D présente des capacités antioxydantes. Il fonctionne à la fois comme un agent antioxydant et comme un régulateur de l'expression enzymatique antioxydante pour contrer les effets néfastes du stress oxydatif cellulaire. CONCLUSION: nous avons montré que l'AB5D pouvait réduire la PGE2 induite par les UVB, l'IL-1α, l'IL-6, IL-8, IL-1RA et le TNFα, ainsi que le superoxyde mitochondrial. Ces résultats suggèrent que l'AB5D pourrait soulager l'érythème en modulant l'inflammation via la PGE2 et via des mécanismes d'antioxydation.

14.
Angew Chem Int Ed Engl ; 63(7): e202318550, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38155101

RESUMO

Noncanonical amino acids (ncAAs) containing tertiary alcohols are valuable as precursors of natural products and active pharmaceutical ingredients. However, the assembly of such ncAA scaffolds from simple material by C-C bond formation remains a challenging task due to the presence of multiple stereocenters and large steric hindrance. In this study, we present a novel solution to this problem through highly selective enzymatic decarboxylative aldol addition. This method allows for the streamlined assembly of multifunctionalized ncAAs with γ-tertiary alcohols from readily available materials, such as L -aspartatic acid and isatins, vicinal diones and keto esters. The modularity of electrophiles furnished four classes of ncAAs with decent efficiency as well as excellent site and stereocontrol. Computational modeling was employed to gain detailed insight into the catalytic mechanism and to provide a rationale for the observed selectivities. The method offers a single-step approach to producing multifunctionalized ncAAs, which can be directly utilized in peptide synthesis and bioactivity assessment.


Assuntos
Álcoois , Aminoácidos , Aminoácidos/química , Catálise
15.
Anal Chem ; 95(29): 10939-10946, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37430188

RESUMO

The utilization of a building-block-based molecular network is an efficient approach to investigate the unknown chemical space of natural products. However, structure-based automated MS/MS data mining remains challenging. This study introduces building block extractor, a user-friendly MS/MS data mining program that automatically extracts user-defined specified features. In addition to the characteristic product ions and neutral losses, this program integrates the abundance of the product ions and sequential neutral loss features as building blocks for the first time. The discovery of nine undescribed sesquiterpenoid dimers from Artemisia heptapotamica highlights the power of this tool. One of these dimers, artemiheptolide I (9), exhibited in vitro inhibition of influenza A/Hongkong/8/68 (H3N2) with an IC50 of 8.01 ± 6.19 µM. Furthermore, two known guaianolide derivatives (16 and 17) possessed remarkable antiviral activity against influenza A/Puerto Rico/8/1934 H1N1, H3N2, and influenza B/Lee/40 with IC50 values ranging from 3.46 to 11.77 µM. In addition to the efficient discovery of novel natural products, this strategy can be generally applied to grab derivatives with specific fragments and enhance the annotation power of LC-MS/MS analysis.


Assuntos
Produtos Biológicos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Espectrometria de Massas em Tandem , Cromatografia Líquida , Produtos Biológicos/análise , Vírus da Influenza A Subtipo H3N2 , Mineração de Dados , Íons
16.
BMC Cancer ; 23(1): 1122, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978366

RESUMO

BACKGROUND: Accumulating evidence indicates that type II cystatin (CST) genes play a pivotal role in several tumor pathological processes, thereby affecting all stages of tumorigenesis and tumor development. However, the prognostic and predictive value of type II CST genes in GC has not yet been investigated. METHODS: The present study evaluated the expression and prognostic value of type II CST genes in GC by using The Cancer Genome Atlas (TCGA) database and the Kaplan-Meier plotter (KM plotter) online database. The type II CST genes related to the prognosis of GC were then screened out. We then validated the expression and prognostic value of these genes by immunohistochemistry. We also used Database for Annotation, Visualization, and Integrated Discovery (DAVID), Gene Multiple Association Network Integration Algorithm (GeneMANIA), Search Tool for the Retrieval of Interacting Genes/Proteins (STRING), nomogram, genome-wide co-expression analysis, and other bioinformatics tools to analyze the value of type II CST genes in GC and the underlying mechanism. RESULTS: The data from the TCGA database and the KM plotter online database showed that high expression of CST2 and CST4 was associated with the overall survival (OS) of patients with GC. The immunohistochemical expression analysis showed that patients with high expression of CST4 in GC tissues have a shorter OS than those with low expression of CST4 (HR = 1.85,95%CI: 1.13-3.03, P = 0.015). Multivariate Cox regression analysis confirmed that the high expression level of CST4 was an independent prognostic risk factor for OS. CONCLUSIONS: Our findings suggest that CST4 could serve as a tumor marker that affects the prognosis of GC and could be considered as a potential therapeutic target for GC.


Assuntos
Cistatinas , Neoplasias Gástricas , Humanos , Prognóstico , Neoplasias Gástricas/patologia , Redes Reguladoras de Genes , Nomogramas , Cistatinas/genética
17.
Nutr Cancer ; 75(3): 761-775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36562548

RESUMO

With the increasing incidence of cancer worldwide, the prevention and treatment of cancer have garnered considerable scientific attention. Traditional chemotherapeutic drugs are highly toxic and associated with substantial side effects; therefore, there is an urgent need for developing new therapeutic agents. Dietary phytochemicals are important in tumor prevention and treatment because of their low toxicity and side effects at low concentrations; however, their exact mechanisms of action remain obscure. DNA damage is mainly caused by physical or chemical factors in the environment, such as ultraviolet light, alkylating agents and reactive oxygen species that cause changes in the DNA structure of cells. Several phytochemicals have been shown inhibit the occurrence and development of tumors by inducing DNA damage. This article reviews the advances in phytochemical research; particularly regarding the mechanisms related to DNA damage and provide a theoretical basis for future chemoprophylaxis research.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Neoplasias/patologia , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Quimioprevenção , Espécies Reativas de Oxigênio , Dano ao DNA
18.
J Org Chem ; 88(24): 17398-17408, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38037667

RESUMO

A facile and efficient method was reported for Cu-catalyzed selective α-alkylation processes of amino acids/peptides and α-bromo esters/ketones through a radical-radical coupling pathway. The reaction displays an excellent functional group tolerance and broad substrate scope, allowing access to desired products in moderate to excellent yields. Notably, this method is distinguished by site-specificity and exhibits total selectivity for aryl glycine motifs over other amino acid units. Furthermore, the practicality of this strategy is certified by the efficient synthesis of the novel SAHA phenylalanine-containing analogue (SPACA).


Assuntos
Aminoácidos , Cobre , Aminoácidos/química , Cobre/química , Inibidores de Histona Desacetilases , Catálise , Alquilação , Fenilalanina
19.
J Org Chem ; 88(7): 4592-4605, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36976534

RESUMO

This paper describes an efficient strategy to promote alkenyl thioetherifications via the Ni-catalyzed cross-coupling of inactivated or ß-aryl-substituted (E)-alkenyl halides with thio-alcohols/phenols. The present strategy with easy-to-operate reaction conditions represents one of the most effective alkenyl C(sp2)-S bond-forming methods via readily accessible nickel catalysis. Notably, the mildly basic conditions employed facilitate access to a broad scope including protected amino acids, saccharides, and heterocycles. Moreover, this work presents its attractive usefulness by the application in late-stage modifications of several structurally complex natural products and pharmaceuticals.

20.
Org Biomol Chem ; 21(11): 2312-2319, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36637123

RESUMO

Chiral oxazoline compounds play an extremely important role in asymmetric synthesis and drug discovery. Herein a simpler, greener and more efficient microwave-assisted protocol to rapidly access chiral oxazolines is developed using aryl nitriles or cyano-containing compounds and chiral ß-amino alcohols as starting materials. The reaction proceeds smoothly in the presence of a recoverable heterogeneous catalyst in either concentrated solution or under solvent-free conditions. The advantages of this method include rapidness, convenience, environmental protection, high atom economy, and excellent yields. The protocol should find wider application in the community in the future.

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