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1.
Curr Issues Mol Biol ; 46(2): 1503-1515, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38392215

RESUMO

The diversity of leaf characteristics, particularly leaf color, underscores a pivotal area of inquiry within plant science. The synthesis and functionality of chlorophyll, crucial for photosynthesis, largely dictate leaf coloration, with varying concentrations imparting different shades of green. Complex gene interactions regulate the synthesis and degradation of chlorophyll, and disruptions in these pathways can result in abnormal chlorophyll production, thereby affecting leaf pigmentation. This study focuses on Bambusa multiplex f. silverstripe, a natural variant distinguished by a spectrum of leaf colors, such as green, white, and green-white, attributed to genetic variations influencing gene expression. By examining the physiological and molecular mechanisms underlying chlorophyll anomalies and genetic factors in Silverstripe, this research sheds light on the intricate gene interactions and regulatory networks that contribute to leaf color diversity. The investigation includes the measurement of photosynthetic pigments and nutrient concentrations across different leaf color types, alongside transcriptomic analyses for identifying differentially expressed genes. The role of key genes in pathways such as ALA biosynthesis, chlorophyll synthesis, photosynthesis, and sugar metabolism is explored, offering critical insights for advancing research and plant breeding practices.

2.
J Exp Bot ; 75(5): 1314-1330, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069660

RESUMO

Sphingolipids are membrane lipids and play critical roles in signal transduction. Ceramides are central components of sphingolipid metabolism that are involved in cell death. However, the mechanism of ceramides regulating cell death in plants remains unclear. Here, we found that ceramides accumulated in mitochondria of accelerated cell death 5 mutant (acd5), and expression of mitochondrion-localized ceramide kinase (ACD5) suppressed mitochondrial ceramide accumulation and the acd5 cell death phenotype. Using immuno-electron microscopy, we observed hyperaccumulation of ceramides in acer acd5 double mutants, which are characterized by mutations in both ACER (alkaline ceramidase) and ACD5 genes. The results confirmed that plants with specific ceramide accumulation exhibited localization of ceramides to mitochondria, resulting in an increase in mitochondrial reactive oxygen species production. Interestingly, when compared with the wild type, autophagy-deficient mutants showed stronger resistance to ceramide-induced cell death. Lipid profiling analysis demonstrated that plants with ceramide accumulation exhibited a significant increase in phosphatidylethanolamine levels. Furthermore, exogenous ceramide treatment or endogenous ceramide accumulation induces autophagy. When exposed to exogenous ceramides, an increase in the level of the autophagy-specific ubiquitin-like protein, ATG8e, associated with mitochondria, where it directly bound to ceramides. Taken together, we propose that the accumulation of ceramides in mitochondria can induce cell death by regulating autophagy.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ceramidas/metabolismo , Ceramidas/farmacologia , Arabidopsis/metabolismo , Mitocôndrias/metabolismo , Autofagia , Morte Celular , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
3.
Neurochem Res ; 49(7): 1665-1676, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38411782

RESUMO

Cerebral ischemic preconditioning (CIP) has been shown to improve brain ischemic tolerance against subsequent lethal ischemia. Reactive astrocytes play important roles in cerebral ischemia-reperfusion. Recent studies have shown that reactive astrocytes can be polarized into neurotoxic A1 phenotype (C3d) and neuroprotective A2 phenotype (S100A10). However, their role in CIP remains unclear. Here, we focused on the role of N-myc downstream-regulated gene 2 (NDRG2) in regulating the transformation of A1/A2 astrocytes and promoting to brain ischemic tolerance induced by CIP. A Sprague Dawley rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) was used. Rats were divided into the following six groups: (1) sham group; (2) CIP group: left middle cerebral artery was blocked for 10 min; (3) MCAO/R group: left middle cerebral artery was blocked for 90 min; (4) CIP + MCAO/R group: CIP was performed 72 h before MCAO/R; (5) AAV-NDRG2 + CIP + MCAO/R group: adeno-associated virus (AAV) carrying NDRG2 was administered 14 days before CIP + MCAO/R; (6) AAV-Ctrl + CIP + MCAO/R group: empty control group. The rats were subjected to neurological evaluation 24 h after the above treatments, and then were sacrificed for 2, 3, 5-triphenyltetraolium chloride staining, thionin staining, immunofluorescence and western blot analysis. In CIP + MCAO/R group, the neurological deficit scores decreased, infarct volume reduced, and neuronal density increased compared with MCAO/R group. Notably, CIP significantly increased S100A10 expression and the number of S100A10+/GFAP+ cells, and also increased NDRG2 expression. MCAO/R significantly decreased S100A10 expression and the number of S100A10+/GFAP+ cells yet increased C3d expression and the number of C3d+/GFAP+ cells and NDRG2 expression, and these trends were reversed by CIP + MCAO/R. Furthermore, over-expression of NDRG2 before CIP + MCAO/R, the C3d expression and the number of C3d+/GFAP+ cells increased, while S100A10 expression and the number of S100A10+/GFAP+ cells decreased. Meanwhile, over-expression of NDRG2 blocked the CIP-induced brain ischemic tolerance. Taken together, these results suggest that CIP exerts neuroprotective effects against ischemic injury by suppressing A1 astrocyte polarization and promoting A2 astrocyte polarization via inhibiting NDRG2 expression.


Assuntos
Astrócitos , Isquemia Encefálica , Infarto da Artéria Cerebral Média , Precondicionamento Isquêmico , Ratos Sprague-Dawley , Animais , Precondicionamento Isquêmico/métodos , Masculino , Astrócitos/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Isquemia Encefálica/metabolismo , Ratos , Proteínas do Tecido Nervoso
4.
PLoS Biol ; 19(4): e3001190, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33844686

RESUMO

Chemical insecticides have been heavily employed as the most effective measure for control of agricultural and medical pests, but evolution of resistance by pests threatens the sustainability of this approach. Resistance-conferring mutations sometimes impose fitness costs, which may drive subsequent evolution of compensatory modifier mutations alleviating the costs of resistance. However, how modifier mutations evolve and function to overcome the fitness cost of resistance still remains unknown. Here we show that overexpression of P450s not only confers imidacloprid resistance in the brown planthopper, Nilaparvata lugens, the most voracious pest of rice, but also leads to elevated production of reactive oxygen species (ROS) through metabolism of imidacloprid and host plant compounds. The inevitable production of ROS incurs a fitness cost to the pest, which drives the increase or fixation of the compensatory modifier allele T65549 within the promoter region of N. lugens peroxiredoxin (NlPrx) in the pest populations. T65549 allele in turn upregulates the expression of NlPrx and thus increases resistant individuals' ability to clear the cost-incurring ROS of any source. The frequent involvement of P450s in insecticide resistance and their capacity to produce ROS while metabolizing their substrates suggest that peroxiredoxin or other ROS-scavenging genes may be among the common modifier genes for alleviating the fitness cost of insecticide resistance.


Assuntos
Hemípteros/efeitos dos fármacos , Resistência a Inseticidas/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Oryza/parasitologia , Peroxirredoxinas/fisiologia , Adaptação Biológica/efeitos dos fármacos , Adaptação Biológica/genética , Alelos , Animais , Mapeamento Cromossômico , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Genes de Insetos/efeitos dos fármacos , Genes Modificadores/efeitos dos fármacos , Genes Modificadores/fisiologia , Estudos de Associação Genética , Aptidão Genética/efeitos dos fármacos , Hemípteros/fisiologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Oryza/efeitos dos fármacos , Peroxirredoxinas/genética , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade
5.
J Org Chem ; 89(12): 8435-8446, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38843406

RESUMO

Both the 3-fluorooxindole and germinal bisphosphonate structural motifs are prevalent in bioactive molecules because of their associated biological activities. We describe an approach to accessing 3,3-disubstituted 3-fluorooxindoles bearing a geminal bisphosphate fragment through a highly enantioselective Michael addition reaction between 3-fluorooxindoles and vinylidene bisphosphonates. These reactions are catalyzed by a commercially available cinchona alkaloid catalyst, have a broad substrate scope concerning 3-fluorooxindoles, and provide the corresponding addition products in a yield of up to 95% with an enantiomeric excess of up to 95%. A reasonable reaction pathway to explain the observed stereochemistry is also proposed.

6.
Immunol Invest ; : 1-22, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622991

RESUMO

Osteoarthritis (OA) is now widely acknowledged as a low-grade inflammatory condition, in which the intrinsic immune system plays a significant role in its pathogenesis. While the involvement of macrophages and T cells in the development of OA has been extensively reviewed, recent research has provided mounting evidence supporting the crucial contribution of NK cells in both the initiation and advancement of OA. Accumulated evidence has emerged in recent years indicating that NK cells play a critical role in OA development and progression. This review will outline the ongoing understanding of the utility of NK cells in the etiology of OA, focusing on how NK cells interact with chondrocytes, synoviocytes, osteoclasts, and other immune cells to influence the course of OA disease.

7.
Am J Emerg Med ; 77: 39-45, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38096638

RESUMO

OBJECTIVE: Patients with dizziness commonly present to Emergency Departments (ED) and 6% of these patients will be diagnosed with acute stroke. The TriAGe+ score comprises of eight clinical parameters and stratifies patients into four risk groups. The Japanese authors reported that the tool performed well, so our aim was to validate this diagnostic tool in our ED in Hong Kong. MATERIALS AND METHODS: A single-center retrospective observational study was conducted in the ED of our university hospital in Hong Kong. The primary outcome was the diagnosis of an acute cerebrovascular event. Receiver operator characteristic (ROC) analysis was performed to determine the best cut-off score. Secondary outcomes included univariable and multivariable analyses of stroke predictors. RESULTS: 455 patients aged 18 years or above with dizziness or vertigo at ED triage were recruited between 19 July and 30 September 2021. The overall prevalence of stroke was 11.9%. The median TriAGe+ score was 7 (IQR = 4-9). The AUC was 0.9. At a cut-off >5, sensitivity was 96.4% (95%CI: 87.3-99.5) and the negative likelihood ratio was 0.09 (95%CI: 0.02-0.3). At a cut-off >10, specificity was 99.8% (95%CI: 98.6-100.0), and the positive likelihood ratio was 237.6 (95%CI: 33.1-1704). On multivariable analyses, atrial fibrillation, blood pressure, gender, dizziness (not vertigo) and no history of dizziness, vertigo or labyrinth/vestibular disease were found to be positively associated with stroke outcomes significantly. CONCLUSION: The TriAGe+ score is an efficient stroke prediction score for patients presenting to the ED with dizziness.


Assuntos
Tontura , Acidente Vascular Cerebral , Humanos , Tontura/diagnóstico , Tontura/epidemiologia , Serviço Hospitalar de Emergência , Hong Kong/epidemiologia , Hospitais Universitários , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Triagem , Vertigem/diagnóstico , Vertigem/epidemiologia , Estudos Retrospectivos
8.
Postgrad Med J ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38679808

RESUMO

BACKGROUND: Low back pain (LBP) is a leading cause of disability worldwide and has posed numerous health and socioeconomic challenges. This study compared whether nonsteroidal anti-inflammatory drugs (NSAIDs) in combination with tramadol, tizanidine or placebo would be the best treatment regime to improve the Roland Morris Disability Questionnaire (RMDQ) scores at 1 week. METHODS: This was a multi-center, double-blind, randomized, and placebo-controlled trial including adult patients with acute LBP and sciatica in three emergency departments in Hong Kong. Patients were randomized to the receive tramadol 50 mg, tizanidine 2 mg, or placebo every 6 hours for 2 weeks in a 1:1:1 ratio. The RMDQ and other secondary outcomes were measured at baseline, Day 2, 7, 14, 21, and 28. Data were analyzed on an intention to treat basis. Crude and adjusted mean differences in the changes of RMDQ and NRS scores from baseline to Day 7 between tizanidine/tramadol and placebo were determined with 95% confidence intervals. RESULTS: Two hundred and ninety-one patients were analyzed with the mean age of 47.4 years and 57.7% were male. The primary outcome of mean difference in RMDQs on Day 7 (compared with baseline) was non-significant for tizanidine compared with placebo (adjusted mean difference - 0.56, 95% CI -2.48 to 1.37) and tramadol compared with placebo (adjusted mean difference - 0.85, 95% CI -2.80 to 1.10). Only 23.7% were fully compliant to the treatment allocated. Complier Average Causal Effect analysis also showed no difference in the primary outcome for the tizanidine and tramadol versus placebo. CONCLUSION: Among patients with acute LBP and sciatica presenting to the ED, adding tramadol or tizanidine to diclofenac did not improve functional recovery.

9.
Zhongguo Zhong Yao Za Zhi ; 49(3): 849-852, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38621889

RESUMO

Chinese drug registration laws and regulations have always reserved a place for the new traditional Chinese medicine(TCM) drugs for syndromes, but so far no such new drugs have been approved for registration. This paper expounded on the relevant policies, regulations, and technologies of new TCM drugs for syndromes in China and pointed out that the application of the animal model of TCM syndromes to carry out pharmacodynamics research and clinical efficacy evaluation criteria of TCM syndromes were the main technical difficulties in the research and development of new TCM drugs for syndromes. Not all syndromes are suitable for developing new drugs, and the indications for new TCM drugs should be constant syndromes. Among the three research and development models of simple syndrome, syndrome-unified disease, and combined disease and syndrome, the research and development model of combined disease and syndrome is recommended. Clinical positioning is the key to new TCM drugs for syndromes. It is encouraged to conduct high-quality human use experience studies to determine the clinical positioning of new TCM drugs for syndromes, as well as the target population, dose, course of treatment, and initial therapeutic and safety, and apply for exemption from non-clinical effectiveness studies. Clinical trials of new TCM drugs for syndromes should take the target symptoms or signs as the main efficacy index and the efficacy of TCM syndromes as the secondary efficacy index. Clinical research program design should implement the "patient-centered" concept and introduce clinical outcome evaluation indicators. In the clinical safety evaluation, special conditions such as characteristic syndromes and changes should be considered. With the construction of the human use experience technology system and the promotion of the TCM registration and evaluation evidence system featuring the "combination of TCM theory, human use experience, and clinical trials", it is believed that many high-quality new TCM drugs for syndromes will be developed in the future.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Pesquisa , Síndrome , China , Medicamentos de Ervas Chinesas/uso terapêutico
10.
Angew Chem Int Ed Engl ; 63(8): e202316706, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38126129

RESUMO

Diarylethene molecular photoswitches hold great fascination as optical information materials due to their unique bistability and exceptional reversible photoswitching properties. Conventional diarylethenes, however, rely on UV light for ring-closure reactions, typically with modest yields. For practical application, diarylethenes driven by visible lights are preferred but achieving high ring-closure reaction yield remains a significant challenge. Herein, we synthesized a novel all-visible-light-driven photoswitch, TPAP-DTE, by facilely endcapping the dithienylethene (DTE) core with triphenylamine phenyl (TPAP) groups. Owing to the electron-donating conjugation effect of TPAP, the open-form TPAP-DTE responds strongly to short-wavelength visible lights with considerable photocyclization quantum yields and molar absorption coefficient. Upon 405 nm visible-light irradiation, TPAP-DTE achieves a ring-closure reaction yield exceeding 96.3 % (confirmed by both nuclear magnetic resonance spectroscopy and high-performance liquid chromatography). Its ring-opening reaction yield is 100 % upon irradiation with long-wavelength visible light. TPAP-DTE could be regarded as a bidirectional "quasi"-quantitative conversion molecular switch. Furthermore, TPAP-DTE exhibits robust fatigue resistance over 100 full photoswitching cycles and great anti-aging property under 85 °C and 85 % humidity for at least 1000 h. Consequently, its rewritable QR-code, multilevel data storage, and anti-counterfeiting/encryption applications are successfully demonstrated exclusively using visible lights, positioning TPAP-DTE as a highly promising medium for information recording.

11.
Plant J ; 109(6): 1427-1440, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34919775

RESUMO

Sphingolipids, a class of bioactive lipids, play a critical role in signal transduction. Ceramides, which are central components of sphingolipid metabolism, are involved in plant development and defense. However, the mechanistic link between ceramides and downstream signaling remains unclear. Here, the mutation of alkaline ceramidase in a ceramide kinase mutant acd5 resulted in spontaneous programmed cell death early in development and was accompanied by ceramide accumulation, while other types of sphingolipids, such as long chain base, glucosylceramide, and glycosyl inositol phosphorylceramide, remained at the same level as the wild-type plants. Analysis of the transcriptome indicated that genes related to the salicylic acid (SA) pathway and oxidative stress pathway were induced dramatically in acer acd5 plants. Comparison of the level of reactive oxygen species (ROS), SA, and ceramides in the wild-type and acer acd5 plants at different developmental stages indicated that the acer acd5 mutant exhibited constitutive activation of SA and ROS signaling, which occurred simultaneously with the alteration of ceramides. Overexpressing NahG in the acer acd5 mutant could completely suppress its cell death and ceramide accumulation, while benzo-(1,2,3)-thiadiazole-7-carbothioc acid S-methyl ester treatment restored its phenotype again. Moreover, we found that the plasma membrane of acer acd5 mutant was the main site of ROS production. Ceramides accumulated in the plasma membrane of acer acd5, directly binding and activating the NADPH oxidase RbohD and promoting hydrogen peroxide generation and SA- or defense-related gene activation. Our data illustrated that ceramides play an essential role in plant defense.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ceramidas/metabolismo , Mutação , Ácido Salicílico/metabolismo , Esfingolipídeos/metabolismo
12.
Int J Cancer ; 153(4): 815-825, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37155342

RESUMO

The combination of immunotherapy and antiangiogenic agents for the treatment of refractory solid tumor has not been well investigated. Thus, our study aimed to evaluate the efficacy and safety of a new regimen of anlotinib plus PD-1 inhibitor to treat refractory solid tumor. APICAL-RST is an investigator-initiated, open-label, single-arm, phase II trial in patients with heavily treated, refractory, metastatic solid tumor. Eligible patients experienced disease progression during prior therapy without further effective regimen. All patients received anlotinib and PD-1 inhibitor. The primary endpoints were objective response and disease control rates. The secondary endpoints included the ratio of progression-free survival 2 (PFS2)/PFS1, overall survival (OS) and safety. Forty-one patients were recruited in our study; 9 patients achieved a confirmed partial response and 21 patients had stable disease. Objective response rate and disease control rate were 22.0% and 73.2% in the intention-to-treat cohort, and 24.3% and 81.1% in the efficacy-evaluable cohort, respectively. A total of 63.4% (95% confidence interval [CI]: 46.9%-77.4%) of the patients (26/41) presented PFS2/PFS1 >1.3. The median OS was 16.8 months (range: 8.23-24.4), and the 12- and 36-month OS rates were 62.8% and 28.9%, respectively. No significant association was observed between concomitant mutation and efficacy. Thirty-one (75.6%) patients experienced at least one treatment-related adverse event. The most common adverse events were hypothyroidism, hand-foot syndrome and malaise. This phase II trial showed that anlotinib plus PD-1 inhibitor exhibits favorable efficacy and tolerability in patients with refractory solid tumor.


Assuntos
Neoplasias , Quinolinas , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias/tratamento farmacológico , Indóis/efeitos adversos , Quinolinas/efeitos adversos
13.
Funct Integr Genomics ; 23(2): 160, 2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37178159

RESUMO

Patients diagnosed with stable coronary artery disease (CAD) are at continued risk of experiencing acute myocardial infarction (AMI). This study aims to unravel the pivotal biomarkers and dynamic immune cell changes, from an immunological, predictive, and personalized viewpoint, by implementing a machine-learning approach and a composite bioinformatics strategy. Peripheral blood mRNA data from different datasets were analyzed, and CIBERSORT was used for deconvoluting human immune cell subtype expression matrices. Weighted gene co-expression network analysis (WGCNA) in single-cell and bulk transcriptome levels was conducted to explore possible biomarkers for AMI, with a particular emphasis on examining monocytes and their involvement in cell-cell communication. Unsupervised cluster analysis was performed to categorize AMI patients into different subtypes, and machine learning methods were employed to construct a comprehensive diagnostic model to predict the occurrence of early AMI. Finally, RT-qPCR on peripheral blood samples collected from patients validated the clinical utility of the machine learning-based mRNA signature and hub biomarkers. The study identified potential biomarkers for early AMI, including CLEC2D, TCN2, and CCR1, and found that monocytes may play a vital role in AMI samples. Differential analysis revealed that CCR1 and TCN2 exhibited elevated expression levels in early AMI compared to stable CAD. Machine learning methods showed that the glmBoost+Enet [alpha=0.9] model achieved high predictive accuracy in the training set, external validation sets, and clinical samples in our hospital. The study provided comprehensive insights into potential biomarkers and immune cell populations involved in the pathogenesis of early AMI. The identified biomarkers and the constructed comprehensive diagnostic model hold great promise for predicting the occurrence of early AMI and can serve as auxiliary diagnostic or predictive biomarkers.


Assuntos
Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/genética , Análise por Conglomerados , Biologia Computacional , Aprendizado de Máquina , RNA Mensageiro/genética
14.
New Phytol ; 240(3): 1134-1148, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37606093

RESUMO

Sphingolipids are cell membrane components and signaling molecules that induce endoplasmic reticulum (ER) stress responses, but the underlying mechanism is unknown. Orosomucoid proteins (ORMs) negatively regulate serine palmitoyltransferase activity, thus helping maintain proper sphingolipid levels in humans, yeast, and plants. In this report, we explored the roles of ORMs in regulating ER stress in Arabidopsis thaliana. Loss of ORM1 and ORM2 function caused constitutive activation of the unfolded protein response (UPR), as did treatment with the ceramide synthase inhibitor Fumonisin B1 (FB1) or ceramides. FB1 treatment induced the transcription factor bZIP28 to relocate from the ER membrane to the nucleus. The transcription factor WRKY75 positively regulates the UPR and physically interacted with bZIP28. We also found that the orm mutants showed impaired ER-associated degradation (ERAD), blocking the degradation of misfolded MILDEW RESISTANCE LOCUS-O 12 (MLO-12). ORM1 and ORM2 bind to EMS-MUTAGENIZED BRI1 SUPPRESSOR 7 (EBS7), a plant-specific component of the Arabidopsis ERAD complex, and regulate its stability. These data strongly suggest that ORMs in the ER membrane play vital roles in the UPR and ERAD pathways to prevent ER stress in Arabidopsis. Our results reveal that ORMs coordinate sphingolipid homeostasis with ER quality control and play a role in stress responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Humanos , Arabidopsis/genética , Arabidopsis/metabolismo , Orosomucoide/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Resposta a Proteínas não Dobradas , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Esfingolipídeos/metabolismo , Ceramidas/metabolismo , Fatores de Transcrição/metabolismo , Saccharomyces cerevisiae/metabolismo
15.
Cell Mol Neurobiol ; 43(3): 1355-1367, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35900650

RESUMO

Cerebral ischemic preconditioning (CIP)-induced brain ischemic tolerance protects neurons from subsequent lethal ischemic insult. However, the specific mechanisms underlying CIP remain unclear. In the present study, we explored the hypothesis that peroxisome proliferator-activated receptor gamma (PPARγ) participates in the upregulation of Klotho during the induction of brain ischemic tolerance by CIP. First we investigated the expression of Klotho during the brain ischemic tolerance induced by CIP. Lethal ischemia significantly decreased Klotho expression from 6 h to 7 days, while CIP significantly increased Klotho expression from 12 h to 7 days in the hippocampal CA1 region. Inhibition of Klotho expression by its shRNA blocked the neuroprotection induced by CIP. These results indicate that Klotho participates in brain ischemic tolerance by CIP. Furthermore, we tested the role of PPARγ in regulating Klotho expression after CIP. CIP caused PPARγ protein translocation to the nucleus in neurons in the CA1 region of the hippocampus. Pretreatment with GW9962, a PPARγ inhibitor, significantly attenuated the upregulation of Klotho protein and blocked the brain ischemic tolerance induced by CIP. Taken together, it can be concluded that Klotho upregulation via PPARγ contributes to the induction of brain ischemic tolerance by CIP.


Assuntos
Isquemia Encefálica , Precondicionamento Isquêmico , Animais , Ratos , Isquemia Encefálica/metabolismo , Região CA1 Hipocampal , Isquemia , PPAR gama/metabolismo , Ratos Wistar , Regulação para Cima
16.
Anticancer Drugs ; 34(10): 1146-1150, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728908

RESUMO

The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) dramatically improve the clinical outcomes of non-small cell lung cancer (NSCLC) patients harboring EGFR -sensitive mutations. Despite the remarkable efficacy of first-and second-generation EGFR TKIs, disease relapse is inevitable. EGFR T790M mutation is a primary contributor to the acquired resistance to first- and second-generation EGFR TKIs. Osimertinib, which is an irreversible third-generation EGFR TKI, was designed for EGFR -activating mutations as well as the EGFR T790M mutation in patients with advanced NSCLC and has demonstrated a convincing efficacy. However, acquired resistance to osimertinib after treatment inevitably occurs. The acquired resistance mechanisms to osimertinib are highly complicated and not fully understood, encompassing EGFR -dependent as well as EGFR -independent mechanisms. Treatment approaches for patients progressing from osimertinib have not been established. We present a case of a stage IV lung adenocarcinoma patient harboring EGFR L858R, acquired T790M after treatment with first-line gefitinib. She then acquired a new EML4-ALK gene fusion after treatment with osimertinib. A combination targeted therapy of osimertinib plus alectinib was initiated, with a progression-free survival of 5 months without any serious adverse reaction. After disease progression, EGFR C797S in cis was detected with a loss of the EML4-ALK fusion by targeted next-generation sequencing. Then therapy was changed to pemetrexed combined with bevacizumab plus camrelizumab, but no obvious effect was observed. The patient had achieved an overall survival of 31 months. As far as we know, this was the first reported case that an EGFR -mutant NSCLC patient-acquired ALK fusion mediating resistance to osimertinib, and sequential EGFR C797S mutation mediating resistance to combined targeted therapy with osimertinib and alectinib. Our case shows that EML4-ALK fusion is a rare but critical resistance mechanism to osimertinib, and C797S mutation in cis may be an underlying mechanism of acquired resistance mutation in double TKIs therapy. Furthermore, molecular detection and rebiopsy play important roles in the selection of therapeutic strategies when the disease progresses.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Feminino , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Receptores ErbB/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Compostos de Anilina/uso terapêutico , Compostos de Anilina/farmacologia , Proteínas de Fusão Oncogênica
17.
Eur Radiol ; 33(11): 8165-8176, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37145150

RESUMO

OBJECTIVES: To explore the clinical potential of multiparametric cardiac magnetic resonance (CMR) in evaluating myocardial inflammation in patients with exertional heat illness (EHI). METHODS: This prospective study enrolled 28 males with EHI (18 patients with exertional heat exhaustion (EHE) and 10 with exertional heat stroke (EHS)) and 18 age-matched male healthy controls (HC). All subjects underwent multiparametric CMR, and 9 patients had follow-up CMR measurements 3 months after recovery from EHI. CMR-derived left ventricular geometry, function, strain, native T1, extracellular volume (ECV), T2, T2*, and late gadolinium enhancement (LGE) were obtained and compared among different groups. RESULTS: Compared with HC, EHI patients showed increased global ECV, T2, and T2* values (22.6% ± 4.1 vs. 19.7% ± 1.7; 46.8 ms ± 3.4 vs. 45.1 ms ± 1.2; 25.5 ms ± 2.2 vs. 23.8 ms ± 1.7; all p < 0.05). Subgroup analysis showed that ECV was higher in the EHS patients than those in EHE and HC groups (24.7% ± 4.9 vs. 21.4% ± 3.2, 24.7% ± 4.9 vs. 19.7% ± 1.7; both p < 0.05). Repeated CMR measurements at 3 months after baseline CMR showed persistently higher ECV than HC (p = 0.042). CONCLUSIONS: With multiparametric CMR, EHI patients demonstrated increased global ECV, T2, and persistent myocardial inflammation at 3-month follow-up after EHI episode. Therefore, multiparametric CMR might be an effective method in evaluating myocardial inflammation in patients with EHI. CLINICAL RELEVANCE STATEMENT: This study showed persistent myocardial inflammation after an exertional heat illness (EHI) episode demonstrated by multiparametric CMR, which is a potential promising method to evaluate the severity of myocardial inflammation and guide return to work, play, or duty in EHI patients. KEY POINTS: • EHI patients showed an increased global extracellular volume (ECV), late gadolinium enhancement, and T2 value, indicating myocardial edema and fibrosis. • ECV was higher in the exertional heat stroke patients than exertional heat exhaustion and healthy control groups (24.7% ± 4.9 vs. 21.4% ± 3.2, 24.7% ± 4.9 vs. 19.7% ± 1.7; both p < 0.05). • EHI patients showed persistent myocardial inflammation with higher ECV than healthy controls 3 months after index CMR (22.3% ± 2.4 vs. 19.7% ± 1.7, p = 0.042).


Assuntos
Exaustão por Calor , Golpe de Calor , Miocardite , Humanos , Masculino , Meios de Contraste/farmacologia , Estudos Prospectivos , Exaustão por Calor/patologia , Gadolínio , Função Ventricular Esquerda , Imagem Cinética por Ressonância Magnética , Estudos de Casos e Controles , Miocárdio/patologia , Espectroscopia de Ressonância Magnética , Golpe de Calor/complicações , Golpe de Calor/diagnóstico por imagem , Golpe de Calor/patologia , Inflamação/diagnóstico por imagem , Inflamação/patologia , Valor Preditivo dos Testes
18.
J Org Chem ; 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37384900

RESUMO

A 1,1'-bi-2-naphthol (BINOL)-derived disulfonimide (DSI)-catalyzed enantioselective aza-Friedel-Crafts reaction between 1,3,5-trialkoxy benzenes and N-sulfonyl aldimines gives direct access to a series of chiral diarylmethylamines in good yields and good to excellent enantioselectivities (up to 97% ee). This reaction provides a useful protocol for the direct synthesis of diarylmethylamine derivatives.

19.
Bioorg Chem ; 133: 106407, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36758275

RESUMO

(±)-Yanhusuomide A (1), a novel enantiomeric pair of ornithine-fused benzylisoquinoline, were characterized from the dried tubers of Corydalis yanhusuo, along with a biogenetically related intermediate oblongine (2). Yanhusuomide A features an unprecedented skeleton based on a benzylisoquinoline coupled with an ornithine derivative to form a rare 5,6-dihydro-4H-pyrido[3,4,5-de]quinazoline motif. Plausible biosynthetic pathway of 1 was proposed, and (±)-yanhusuomide A (1) presented potential inhibitory bioactivity against acetylcholinesterase (AChE) with IC50 = 14.07 ± 2.38 µM. The simulation of molecular docking displayed that 1 generated strong interaction with Asp-74 and Trp-86 residues of AChE through attractive charge of the quaternary nitrogen.


Assuntos
Benzilisoquinolinas , Corydalis , Acetilcolinesterase , Benzilisoquinolinas/química , Corydalis/química , Simulação de Acoplamento Molecular , Tubérculos/química
20.
Bioorg Chem ; 130: 106201, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36327683

RESUMO

Thirteen new alkaloids (1-13) as well as ten known compounds were isolated from the solid-state fermented rice medium of the fungus Chaetomium nigricolor YT-2. Their structures were elucidated on the basis of spectroscopic data, quantum calculations, and single crystal X-ray crystallographic analysis. Chaetonigrisin A (1) represents an unprecedented carbon skeleton featuring a polycyclic 1H-pyrano[3,2:3,4-]​furo[2,​3-​b]​indole. Chaetonigrisin B (2) displays a unique carbon skeleton with a 1,3­dioxolane bridged-ring. Chaetonigrisin C (3) is a spirocyclic indole alkaloid. Chaetonigrisins D-H (4-8) are a group of asymmetric dimers, formed with two 3-indol-3yl-1,2-propanediol (4-6) or with a 3-indol-3yl-1,2-propanediol and a 3-indol-2yl-1,2-propanediol (7-8) by a pyran ring. Chaetonigrisins I-L (9-12) each contains a 3-indol-3yl-1,2-propanediol or 3-indol-2yl-1,2-propanediol substructure. Chaetonigrisin M (13) is a new quinoline alkaloid. The neuroprotective activity assay showed that at the concentration of 40 µM, compounds (4-7, 11, and 12) improved the cell viability of PC12 cells were 49.26 %, 74.69 %, 74.76 %, 86.63 %, 66.89 %, and 69.92 %, respectively induced by 6-OHDA, compound 7 showed significant neuroprotective activity via upregulation of SOD1 mRNA and Bcl-2 mRNA.


Assuntos
Alcaloides , Chaetomium , Chaetomium/química , Propilenoglicol , Alcaloides Indólicos/química , Alcaloides/química , Carbono , RNA Mensageiro , Estrutura Molecular
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