Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 196
Filtrar
1.
Nutr Cancer ; : 1-10, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38733116

RESUMO

Cervical cancer (CC) is a common gynecological malignancy, and improving cisplatin sensitivity has become a hot topic in CC chemotherapy research. Polyphyllin I (PPI), a potent bioactive compound found in Rhizoma Paridis, known for its anticancer properties, remains underexplored in CC resistance. In this study, we evaluated PPI's impact on cisplatin-resistant CC cells and elucidated its underlying mechanism. Our findings reveal that PPI enhances the sensitivity of cisplatin-resistant CC cells to the drug, promotes apoptosis, and inhibits cell migration. Mechanistically, PPI was found to regulate p53 expression and its target genes, and suppressing p53 expression reverses PPI's sensitizing effect in drug-resistant CC cells. In conclusion, PPI showed promise in sensitizing cisplatin-resistant human CC cells to cisplatin treatment, suggesting that it could serve as a potent adjunct therapy for cervical cancer, particularly for cases that have developed resistance to cisplatin, thereby providing a promising basis for further clinical investigation into PPI for enhancing the efficacy of existing chemotherapy regimens in resistant cervical cancer.

2.
Int J Mol Sci ; 25(9)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38732273

RESUMO

Drought and salinity stress reduce root hydraulic conductivity of plant seedlings, and melatonin application positively mitigates stress-induced damage. However, the underlying effect of melatonin priming on root hydraulic conductivity of seedlings under drought-salinity combined remains greatly unclear. In the current report, we investigated the influence of seeds of three wheat lines' 12 h priming with 100 µM of melatonin on root hydraulic conductivity (Lpr) and relevant physiological indicators of seedlings under PEG, NaCl, and PEG + NaCl combined stress. A previous study found that the combined PEG and NaCl stress remarkably reduced the Lpr of three wheat varieties, and its value could not be detected. Melatonin priming mitigated the adverse effects of combined PEG + NaCl stress on Lpr of H4399, Y1212, and X19 to 0.0071 mL·h-1·MPa-1, 0.2477 mL·h-1·MPa-1, and 0.4444 mL·h-1·MPa-1, respectively, by modulating translation levels of aquaporin genes and contributed root elongation and seedlings growth. The root length of H4399, Y1212, and X19 was increased by 129.07%, 141.64%, and 497.58%, respectively, after seeds pre-treatment with melatonin under PEG + NaCl combined stress. Melatonin -priming appreciably regulated antioxidant enzyme activities, reduced accumulation of osmotic regulators, decreased levels of malondialdehyde (MDA), and increased K+ content in stems and root of H4399, Y1212, and X19 under PEG + NaCl stress. The path investigation displayed that seeds primed with melatonin altered the modification of the path relationship between Lpr and leaf area under stress. The present study suggested that melatonin priming was a strategy as regards the enhancement of root hydraulic conductivity under PEG, NaCl, and PEG + NaCl stress, which efficiently enhanced wheat resistant to drought-salinity stress.


Assuntos
Secas , Melatonina , Raízes de Plantas , Salinidade , Plântula , Sementes , Triticum , Melatonina/farmacologia , Triticum/efeitos dos fármacos , Triticum/genética , Triticum/fisiologia , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/genética , Estresse Fisiológico/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Salino , Cloreto de Sódio/farmacologia , Antioxidantes/metabolismo , Água/metabolismo
3.
Org Lett ; 26(15): 3043-3047, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38578846

RESUMO

We disclose a deconstructive [5 + 1] annulation protocol for the synthesis of isoquinolones through a nitrogen insertion into abundant indanones. This method exploits photoredox-catalyzed ring-opening of oxime esters. The reaction proceeds smoothly with water as the reaction medium and tolerates a range of functional groups on diverse thiophenols, amines, or indanones. Moreover, the representative isoquinolones exhibit promising antifungal activities.

4.
Aging Ment Health ; : 1-10, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566487

RESUMO

OBJECTIVES: The built environment is increasingly recognized as being associated with late-life loneliness. However, the pathway remains understudied. This study investigated the mediating effects of productive engagement in relationships between the built environment and loneliness. METHODS: We conducted a cross-sectional analysis of data from 4,409 community-dwelling people aged 65 years and above in China. We employed the Chinese version of the De Jong Gierveld Loneliness Scale to assess loneliness. The built environment comprises residential density, street connectivity, park-based and vegetation-based green space, land use mix, and the number of and distance to the nearest recreational, health, shopping and community services within 300-meter and 500-meter buffer areas. Structural equation modeling was used. RESULTS: Only green space (parks) had a direct effect on loneliness. Residential density and green space (parks) had an indirect effect on loneliness through volunteering. The number of recreational services had an indirect effect on loneliness through recreational and sporting activities, although distance to the nearest recreational services did not. All the significant results were only found within 300-meter rather than 500-meter buffers. CONCLUSIONS: Our findings have implications for environmental gerontology theory and practice. Providing more green space and recreational services can significantly improve older adults' helping behavior, social activities and sporting activities, which can further reduce older adults' loneliness.

5.
Apoptosis ; 29(5-6): 785-798, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38517601

RESUMO

Osteoarthritis (OA) is a common disease in middle-aged and elderly people. An imbalance in calcium ion homeostasis will contribute to chondrocyte apoptosis and ultimately lead to the progression of OA. Transient receptor potential channel 4 (TRPV4) is involved in the regulation of intracellular calcium homeostasis. TRPV4 is expressed in primary cilia, which can sense mechanical stimuli from outside the cell, and its abnormal expression is closely related to the development of OA. Low-intensity pulsed ultrasound (LIPUS) can alleviate chondrocyte apoptosis while the exact mechanism is unclear. In this project, with the aim of revealing the mechanism of action of LIPUS, we proposed to use OA chondrocytes and animal models, LIPUS intervention, inhibition of primary cilia, use TRPV4 inhibitors or TRPV4 agonist, and use Immunofluorescence (IF), Immunohistochemistry (IHC), Western Blot (WB), Quantitative Real-time PCR (QP) to detect the expression of cartilage synthetic matrix and endoplasmic reticulum stress markers. The results revealed that LIPUS altered primary cilia expression, promoted synthetic matrix metabolism in articular chondrocytes and was associated with primary cilia. In addition, LIPUS exerted a active effect on OA by activating TRPV4, inducing calcium inward flow, and facilitating the entry of NF-κB into the nucleus to regulate synthetic matrix gene transcription. Inhibition of TRPV4 altered primary cilia expression in response to LIPUS stimulation, and knockdown of primary cilia similarly inhibited TRPV4 function. These results suggest that LIPUS mediates TRPV4 channels through primary cilia to regulate the process of knee osteoarthritis in mice.


Assuntos
Condrócitos , Cílios , Osteoartrite do Joelho , Canais de Cátion TRPV , Animais , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Cílios/metabolismo , Cílios/patologia , Camundongos , Condrócitos/metabolismo , Condrócitos/patologia , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/terapia , Apoptose/genética , Progressão da Doença , Camundongos Endogâmicos C57BL , Masculino , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Modelos Animais de Doenças , Cálcio/metabolismo , Estresse do Retículo Endoplasmático , Humanos
6.
Aquac Nutr ; 2024: 8886237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469394

RESUMO

Betaine, a methyl donor, plays a crucial role in lipid metabolism. Previous studies have shown that appropriate betaine supplementation in a high-fat diet reduces triglycerides (TG) of serum and hepatopancreas in fish. However, the underlying mechanism remains unclear. This study examined whether betaine can enhance the secretion of very low-density lipoprotein (VLDL) and sought to identify the specific mechanisms through which this enhancement occurs. A lipid accumulation model was established in gibel carp and L8824 cells using a high-fat diet and oleic acid, respectively. Different doses of betaine (1, 4, and 16 g/kg in the diet; 400 µmol in cell culture) were administered, and measurements were taken for lipid deposition, gene expression of HNF4α, MTTP, and ApoB, as well as the regulation of Mttp and Apob promoters by HNF4α. The results showed that betaine supplementation mitigated lipid droplet accumulation, TG levels, and VLDL production induced by the high-fat diet in gibel carp hepatopancreas and L8824 cells. Moreover, betaine not only increased VLDL content in the cell culture supernatant but also reversed the inhibitory effects of the high-fat diet on protein expression of MTTP, ApoB, and HNF4α in both gibel carp hepatopancreas and L8824 cells. Additionally, HNF4α exhibits transactivating activity on the promoter of Mttp in gibel carp. These findings suggest that betaine supplementation exerts its effects through the HNF4α/MTTP/ApoB pathway, promoting the assembly and secretion of VLDL and effectively reducing lipid accumulation in the hepatopancreas of farmed gibel carp fed a high-fat diet.

7.
Adv Sci (Weinh) ; : e2308181, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459671

RESUMO

Developing synthetic molecular devices for controlling ion transmembrane transport is a promising research field in supramolecular chemistry. These artificial ion channels provide models to study ion channel diseases and have huge potential for therapeutic applications. Compared with self-assembled ion channels constructed by intermolecular weak interactions between smaller molecules or cyclic compounds, metallacage-based ion channels have well-defined structures and can exist as single components in the phospholipid bilayer. A naphthalene diimide-based artificial chloride ion channel is constructed through efficient subcomponent self-assembly and its selective ion transport activity in large unilamellar vesicles and the planar lipid bilayer membrane by fluorescence and ion-current measurements is investigated. Molecular dynamics simulations and density functional theory calculations show that the metallacage spans the entire phospholipid bilayer as an unimolecular ion transport channel. This channel transports chloride ions across the cell membrane, which disturbs the ion balance of cancer cells and inhibits the growth of cancer cells at low concentrations.

8.
Neoplasia ; 50: 100979, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38387107

RESUMO

BACKGROUND: Despite promising overall survival of stage I lung adenocarcinoma (LUAD) patients, 10-25 % of them still went through recurrence after surgery. [1] While it is still disputable whether adjuvant chemotherapy is necessary for stage I patients. [2] IASLC grading system for non-mucinous LUAD shows that minor high-grade patterns are significant indicator of poor prognosis. [3] Other risk factors, such as, pleura invasion, lympho-vascular invasion, STAS, etc. are also related to poor prognosis. [4-6] There still lack evidence whether IASLC grade itself or together with other risk factors can guide the use of adjuvant therapy in stage I patients. In this article, we tried to establish a multi-variable recurrence prediction model for stage I LUAD patients that is able to identify candidates of adjuvant chemotherapy. METHODS: We retrospectively collected patients who underwent lung surgery from 2018.8.1 to 2018.12.31 at our institution and diagnosed with lung adenocarcinoma pT1-2aN0M0 (stage I). Clinical data, manifestation on CT scan, pathologic features, driver gene mutations and follow-up information were collected. Cox proportional hazards regression analyses were performed utilizing the non-adjuvant cohort to predict disease free survival (DFS) and a nomogram was constructed and applied to the total cohort. Kaplan-Meier method was used to compare DFS between groups. Statistical analysis was conducted by R version 3.6.3. FINDINGS: A total of 913 stage I LUAD patients were included in this study. Median follow-up time is 48.1 months.4-year and 5-year DFS are 92.9 % and 89.6 % for the total cohort. 65 patient experienced recurrence or death. 4-year DFS are 97.0 %,94.6 % and 76.2 %, and 5-year DFS are 95.5 %, 90.0 % and 74.1 % in IASLC Grade1, 2 and 3, respectively(p < 0.0001). High-risk patients defined by single risk factors, such as, IASLC grade 3, pleura invasion, STAS, less LN resected could not benefit from adjuvant therapy. A LASSO-COX regression model was built and patients are divided into high-risk and low-risk groups. In the high-risk group, patients underwent adjuvant chemotherapy have longer DFS than those who did not (p = 0.024), while in the low-risk group, patients underwent adjuvant chemotherapy have inferior DFS than those who did not (p < 0.001). INTERPRETATION: IASLC grading is a significant indicator of DFS, however it could not guide adjuvant therapy in our stage I LUAD cohort. Growth patterns and T indicators together with other risk factors could identify high-risk patients that are potential candidate of adjuvant therapy, including some stage IA LUAD patients.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Quimioterapia Adjuvante , Estadiamento de Neoplasias , Prognóstico
9.
J Am Heart Assoc ; 13(5): e032084, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38420789

RESUMO

BACKGROUND: This study aimed to investigate the causal relationships between branched-chain amino acids (BCAAs) and the risks of hypertension via meta-analysis and Mendelian randomization analysis. METHODS AND RESULTS: A meta-analysis of 32 845 subjects was conducted to evaluate the relationships between BCAAs and hypertension. In Mendelian randomization analysis, independent single-nucleotide polymorphisms associated with BCAAs at the genome-wide significance level were selected as the instrumental variables. Meanwhile, the summary-level data for essential hypertension and secondary hypertension end points were obtained from the FinnGen study. As suggested by the meta-analysis results, elevated BCAA levels were associated with a higher risk of hypertension (isoleucine: summary odds ratio, 1.26 [95% CI, 1.08-1.47]; leucine: summary odds ratio, 1.28 [95% CI, 1.07-1.52]; valine: summary odds ratio, 1.32 [95% CI, 1.12-1.57]). Moreover, the inverse variance-weighted method demonstrated that an elevated circulating isoleucine level might be the causal risk factor for essential hypertension but not secondary hypertension (essential hypertension: odds ratio, 1.22 [95% CI, 1.12-1.34]; secondary hypertension: odds ratio, 0.96 [95% CI, 0.54-1.68]). CONCLUSIONS: The increased levels of 3 BCAAs positively correlated with an increased risk of hypertension. Particularly, elevated isoleucine level is a causal risk factor for essential hypertension. Increased levels of leucine and valine also tend to increase the risk of essential hypertension, but further verification is still warranted.


Assuntos
Aminoácidos de Cadeia Ramificada , Hipertensão , Humanos , Aminoácidos de Cadeia Ramificada/metabolismo , Isoleucina/genética , Leucina , Análise da Randomização Mendeliana , Valina , Hipertensão/epidemiologia , Hipertensão/genética , Hipertensão/induzido quimicamente , Hipertensão Essencial , Estudo de Associação Genômica Ampla
10.
Clin Transl Med ; 14(2): e1543, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38303608

RESUMO

BACKGROUND: Mutations in one or more genes responsible for encoding subunits within the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin-remodelling complexes are found in approximately 25% of cancer patients. Bromodomain containing 9 (BRD9) is a more recently identified protein coding gene, which can encode SWI/SNF chromatin-remodelling complexes subunits. Although initial evaluations of the potential of BRD9-based targeted therapy have been explored in the clinical application of a small number of cancer types, more detailed study of the diagnostic and prognostic potential, as well as the detailed biological mechanism of BRD9 remains unreported. METHODS: We used various bioinformatics tools to generate a comprehensive, pan-cancer analyses of BRD9 expression in multiple disease types described in The Cancer Genome Atlas (TCGA). Experimental validation was conducted in tissue microarrays and cell lines derived from lung and colon cancers. RESULTS: Our study revealed that BRD9 exhibited elevated expression in a wide range of tumours. Analysis of survival data and DNA methylation for BRD9 indicated distinct conclusions for multiple tumours. mRNA splicing and molecular binding were involved in the functional mechanism of BRD9. BRD9 may affect cancer progression through different phosphorylation sites or N6 -methyladenosine site modifications. BRD9 could potentially serve as a novel biomarker for diagnosing different cancer types, especially could accurately forecast the prognosis of melanoma patients receiving anti-programmed cell death 1 immunotherapy. BRD9 has the potential to serve as a therapeutic target, when pairing with etoposide in patients with melanoma. The BRD9/SMARCD1 axis exhibited promising discriminative performance in forecasting the prognosis of patients afflicted with liver hepatocellular carcinoma (LIHC) and mesothelioma. Additionally, this axis appears to potentially influence the immune response in LIHC by regulating the programmed death-ligand 1 immune checkpoint. For experimental validation, high expression levels of BRD9 were observed in tumour tissue samples from both lung and colon cancer patients. Knocking down BRD9 led to the inhibition of lung and colon cancer development, likely via the Wnt/ß-catenin signalling pathway. CONCLUSIONS: These pan-cancer study revealed the diagnostic and prognostic potential, along with the biological mechanism of BRD9 as a novel therapeutic target in human tumours.


Assuntos
Proteínas que Contêm Bromodomínio , Neoplasias , Fatores de Transcrição , Humanos , Cromatina , Proteínas Cromossômicas não Histona/genética , Neoplasias do Colo , Melanoma/diagnóstico , Melanoma/tratamento farmacológico , Melanoma/genética , Prognóstico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias/diagnóstico , Neoplasias/genética
11.
Diabetes Obes Metab ; 26(5): 1830-1836, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38361455

RESUMO

AIM: There are limited data to evaluate hospitalization for heart failure (hHF) in non-Hispanic Black (hereafter Black) or non-Hispanic White (hereafter White) individuals without previous hHF. Our goal was to evaluate the risk of hHF among Black versus White patients with type 2 diabetes (T2DM) who were initially prescribed empagliflozin using real-world data. METHODS: This multicentre retrospective cohort study included participants aged ≥18 years who had T2DM, were either Black or White, had no previous hHF, and were prescribed empagliflozin between August 2014 and December 2019. Our primary outcome was time to first hHF after the initial prescription of empagliflozin. A propensity-score (PS)-weighted analysis was performed to balance characteristics by race. The inverse probability treatment weighting method based on PS was used to make treatment comparisons. To compare Black with White, a PS-weighted Cox's cause-specific hazards model was used. RESULTS: In total, 8789 participants were eligible for inclusion (Black = 3216 vs. White = 5573). The Black cohort was significantly younger, had a higher proportion of females, and had a higher prevalence of chronic kidney disease, hypertension and diabetic retinopathy, while the White cohort had a higher prevalence of coronary artery disease. After adjustment for confounding factors such as age, gender, coronary artery disease, hypertension and diabetic retinopathy, the hazard ratio for first-time hHF was not significantly different between the two racial groups [hazard ratio (95% confidence interval) = 1.09 (0.84-1.42), p = .52]. CONCLUSION: This study showed no significant difference in incident hHF among Black versus White individuals with T2DM following a prescription for empagliflozin.


Assuntos
Compostos Benzidrílicos , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Glucosídeos , Insuficiência Cardíaca , Hipertensão , Adulto , Feminino , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Hospitalização , Estudos Retrospectivos , Fatores de Risco , População Branca , Negro ou Afro-Americano , Masculino
12.
Int Immunopharmacol ; 126: 111268, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37992442

RESUMO

Both preclinical and clinical studies have extensively proven the effectiveness of TIGIT inhibitors in tumor immunotherapy. However, it has been discovered that the presence of CD226 on tumor-infiltrating lymphocytes is crucial for the effectiveness of both anti-TIGIT therapy alone and when combined with anti-PD-1 therapy for tumors. In our investigation, we observed that cordycepin therapy significantly augmented the expression of the Cd226 gene. As a result, it was hypothesized that cordycepin therapy could enhance the effectiveness of anti-TIGIT therapy. By employing single-cell RNA sequencing analysis of immune cells in the MC38 tumor model, we discovered that cordycepin combined with anti-TIGIT therapy led to a significant increase in the proportion of NK cells within the tumor immune microenvironment. This increased NK cell activity and decreased the expression of inhibitory receptors and exhaustion marker genes. In the combination therapy group, CD8+ T cells had lower exhaustion state scores and increased cytotoxicity, indicating a better immune response. The combination therapy group increased DCs in the tumor immune microenvironment and promoted cellular interaction with CD4+ T cell and CD8+ T cell populations while decreasing Treg cell interactions. In conclusion, cordycepin with anti-TIGIT therapy in colon cancer could reshape the tumor immune microenvironment and have notable anticancer effects.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias do Colo , Humanos , Receptores Imunológicos/metabolismo , Análise de Sequência de RNA , Microambiente Tumoral
13.
J Surg Res ; 295: 763-769, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38150868

RESUMO

INTRODUCTION: Despite advances in colorectal cancer (CRC) treatment, racial disparities persist. The primary aims of the study were to: evaluate differences in molecular testing rates over time by race; and measure the incidence of tumor mutations by race in patients with metastatic CRC. METHODS: A retrospective cohort study was performed of all adult patients with stage IV CRC (2008-2018) identified within the cancer registry of a large regional health system. Demographic/clinical characteristics were collected through primary data abstraction of the electronic health record. Molecular profiling results were obtained directly from Caris Molecular Intelligence and electronic health record. RESULTS: Three hundred eighty-three patients were included: 40.5% (n = 155) were Black and 59.5% (n = 228) were White. Significant increases were observed in microsatellite instability (MSI), KRAS, and BRAF testing rates during the study period (P < 0.0001). The odds of testing over time increased more significantly in Black compared to White patients for MSI testing (White: odds ratio [OR] 1.26 [95% confidence interval [CI] 1.12-1.41], Black: OR 1.69 [95% CI 1.41-2.02], P = 0.005) and BRAF testing (White: OR 1.42 [95% CI 1.26-1.62], Black: OR 1.89 [95% CI 1.51-2.36], P = 0.027). An increase in KRAS testing over time was observed for both cohorts and was independent of race (P = 0.58). Mutation rates did not differ by race: KRAS (Black 55.8% versus White 45.6%, P = 0.13) and BRAF (Black 4.8% versus White 10.0%, P = 0.33). CONCLUSIONS: Within a large regional health system, molecular testing rates in patients with metastatic CRC increased significantly following National Comprehensive Cancer Network guideline changes for both Black and White patients. Black and White patients who underwent molecular testing had similar rates of MSI, KRAS, and BRAF mutations.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Adulto , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Taxa de Mutação , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Estudos Retrospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores Raciais , Mutação , Instabilidade de Microssatélites , Prognóstico
14.
Autophagy ; 20(3): 645-658, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38146933

RESUMO

ATG4B is a core protein and essential for cleaving precursor MAP1LC3/LC3 or deconjugating lipidated LC3-II to drive the formation of autophagosomes. The protein stability and activity of ATG4B regulated by post-translational modification (ubiquitination) will directly affect macroautophagy/autophagy. However, the mechanism involved in ATG4B ubiquitination is largely unclear. In this study, a new E3 ligase of ATG4B, UBE3C, was identified by mass spectra. UBE3C mainly assembles K33-branched ubiquitin chains on ATG4B at Lys119 without causing ATG4B degradation. In addition, the increased ubiquitination of ATG4B caused by UBE3C overexpression inhibits autophagy flux in both normal and starvation conditions, which might be due to the reduced activity of ATG4B and ATG4B-LC3 interaction. This reduction could be reversed once the lysine 119 of ATG4B was mutated to arginine. More important, under starvation conditions the interaction between ATG4B and UBE3C apparently decreased followed by the removal of the K33-branched ubiquitin chain of ATG4B. Thus, starvation-induced autophagy could be partially suppressed by an increased ubiquitination level of ATG4B. In conclusion, our research reveals a novel modification mode of ATG4B in which UBE3C can fine tune ATG4B activity by specific ubiquitination regulating autophagy without causing ATG4B degradation.Abbreviation: ATG: autophagy-related; Baf: bafilomycin A1; CBB: Coomassie Brilliant Blue; CM: complete medium; CQ: chloroquine; GFP: green fluorescent protein; HA-Ub: HA-tagged ubiquitin; IF: immunofluorescence; IP: immunoprecipitation; K: lysine; KO: knockout; K0: all K-to-R mutant; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MS: mass spectrometry; NC: negative control; R: arginine; WCL: whole cell lysate; WT: wild-type.


Assuntos
Autofagia , Lisina , Autofagia/fisiologia , Lisina/metabolismo , Ubiquitinação , Ubiquitina/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Arginina/metabolismo
15.
Front Immunol ; 14: 1275461, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38090588

RESUMO

Background: Little is known on how metabolic reprogramming potentially prompts transition of activated and resting CD4+ memory T cells infiltration in tumor microenvironment of gastric cancer (GC). The study aimed to evaluate their interactions and develop a risk model for predicting prognosis in GC. Methods: Expression profiles were obtained from TCGA and GEO databases. An immunotherapeutic IMvigor210 cohort was also enrolled. CIBERSORT algorithm was used to evaluate the infiltration of immune cells. The ssGSEA method was performed to assess levels of 114 metabolism pathways. Prognosis and correlation analysis were conducted to identify metabolism pathways and genes correlated with activated CD4+ memory T cells ratio (AR) and prognosis. An AR-related metabolism gene (ARMG) risk model was constructed and validated in different cohorts. Flow cytometry was applied to validate the effect of all-trans retinoic acid (ATRA) on CD4+ memory T cells. Results: Since significantly inverse prognostic value and negative correlation of resting and activated CD4+ memory T cells, high AR level was associated with favorable overall survival (OS) in GC. Meanwhile, 15 metabolism pathways including retinoic acid metabolism pathway were significantly correlated with AR and prognosis. The ARMG risk model could classify GC patients with different outcomes, treatment responses, genomic and immune landscape. The prognostic value of the model was also confirmed in the additional validation, immunotherapy and pan-cancer cohorts. Functional analyses revealed that the ARMG model was positively correlated with pro-tumorigenic pathways. In vitro experiments showed that ATRA could inhibit levels of activated CD4+ memory T cells and AR. Conclusion: Our study showed that metabolic reprogramming including retinoic acid metabolism could contribute to transition of activated and resting CD4+ memory T cells, and affect prognosis of GC patients. The ARMG risk model could serve as a new tool for GC patients by accurately predicting prognosis and response to treatment.


Assuntos
Neoplasias Gástricas , Humanos , Células T de Memória , Prognóstico , Linfócitos T CD4-Positivos , Tretinoína , Microambiente Tumoral
16.
Plants (Basel) ; 12(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38140412

RESUMO

To develop optimal management strategies for water and nitrogen fertilizer application in winter wheat cultivation, we conducted a potted experiment to investigate the effects of different irrigation levels and nitrogen fertilizer treatments on the activity of starch synthesis-related enzymes and the grain quality of winter wheat. The potted experiment consisted of three irrigation levels, with the lower limits set at 50-55% (I0), 60-65% (I1), and 70-75% (I2) of the field capacity. In addition, four levels of nitrogen fertilizer were applied, denoted as N0 (0 kg N hm-2), N1 (120 kg N hm-2), N2 (240 kg N hm-2), and N3 (300 kg N hm-2), respectively. The results revealed the significant impacts of irrigation and nitrogen treatments on the activities of key starch-related enzymes, including adenosine diphosphoglucose pyrophosphrylase (ADPG-PPase), soluble starch synthase (SSS), granule-bound starch synthase (GBSS), and starch branching enzymes (SBE) in wheat grains. These treatments also influenced the starch content, amylopectin content, and, ultimately, wheat yield. In summary, our findings suggest that maintaining irrigation at a lower limit of 60% to 65% of the field capacity and applying nitrogen fertilizer at a rate of 240 kg hm-2 is beneficial for achieving both high yield and high quality in winter wheat cultivation.

17.
Plants (Basel) ; 12(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37960086

RESUMO

Low temperature and soil salinization during cotton sowing and seedling adversely affect cotton productivity. Exogenous melatonin (MT) can alleviate the damage caused to plants under non-biological stress; thus, applying MT is a means to improve the growth condition of crops under stress. However, achieving this goal requires a thorough understanding of the physiological regulatory mechanisms of MT on cotton seedlings under low temperature and salinity stress. This study could bring new knowledge on physio-biochemical mechanisms that improve the tolerance of cotton seedlings to combined effects of low temperature and salt stress using an exogenous foliar application of MT. The phytotron experiment comprised two temperature levels of cold stress and control and five MT treatments of 0, 50, 100, 150, and 200 µM and two salinity levels of 0 and 150 mM NaCl. Compared with the control treatments (non-salinity stress under cold stress and control), the combined stress of salt and low temperature reduced cotton seedlings' biomass and net photosynthetic rate (Pn), aggravated the membrane damage, reduced the potassium (K+) content, and increased the sodium (Na+) accumulation in the leaves and roots. Under NaCl stress, exogenously sprayed 50-150 µM MT increased the biomass and gas exchange parameters of cotton seedlings under salt and low temperature combined with salt stress, reduced the degree of membrane damage, and regulated the antioxidant enzyme, ion homeostasis, transport, and absorption of cotton seedlings. The pairwise correlation analysis of each parameter using MT shows that the parameters with higher correlation with MT at cold stress are mainly malondialdehyde (MDA), peroxidase (POD), and catalase (CAT). The highest correlation coefficient at 25 °C is observed between the K+ and Na+ content in cotton seedlings. The conclusion indicates that under salt and low-temperature stress conditions, exogenous application of MT primarily regulates the levels of Pn, superoxide dismutase (SOD), andPOD in cotton seedlings, reduces Na+ and MDA content, alleviates damage to cotton seedlings. Moreover, the most significant effect was observed when an exogenous application of 50-150 µM of MT was administered under these conditions. The current study's findings could serve as a scientific foundation for salinity and low-temperature stress alleviation during the seedling stage of cotton growth.

18.
BMC Plant Biol ; 23(1): 504, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37864143

RESUMO

BACKGROUND: Silicon nanoparticles (SiO2-NPs) play a crucial role in plants mitigating abiotic stress. However, the regulatory mechanism of SiO2-NPs in response to multiple stress remains unclear. The objectives of this study were to reveal the regulatory mechanism of SiO2-NPs on the growth and photosynthesis in cotton seedlings under salt and low-temperature dual stress. It will provide a theoretical basis for perfecting the mechanism of crop resistance and developing the technology of cotton seedling preservation and stable yield in arid and high salt areas. RESULTS: The results showed that the salt and low-temperature dual stress markedly decreased the plant height, leaf area, and aboveground biomass of cotton seedlings by 9.58%, 15.76%, and 39.80%, respectively. While SiO2-NPs alleviated the damage of the dual stress to cotton seedling growth. In addition to reduced intercellular CO2 concentration, SiO2-NPs significantly improved the photosynthetic rate, stomatal conductance, and transpiration rate of cotton seedling leaves. Additionally, stomatal length, stomatal width, and stomatal density increased with the increase in SiO2-NPs concentration. Notably, SiO2-NPs not only enhanced chlorophyll a, chlorophyll b, and total chlorophyll content, but also slowed the decrease of maximum photochemical efficiency, actual photochemical efficiency, photochemical quenching of variable chlorophyll, and the increase in non-photochemical quenching. Moreover, SiO2-NPs enhanced the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase and phosphoenolpyruvate carboxylase, improved leaf water potential, and decreased abscisic acid and malondialdehyde content. All the parameters obtained the optimal effects at a SiO2-NPs concentration of 100 mg L- 1, and significantly increased the plant height, leaf area, and aboveground biomass by 7.68%, 5.37%, and 43.00%, respectively. Furthermore, significant correlation relationships were observed between photosynthetic rate and stomatal conductance, stomatal length, stomatal width, stomatal density, chlorophyll content, maximum photochemical efficiency, actual photochemical efficiency, photochemical quenching of variable chlorophyll, and Rubisco activity. CONCLUSION: The results suggested that the SiO2-NPs improved the growth and photosynthesis of cotton seedlings might mainly result from regulating the stomatal state, improving the light energy utilization efficiency and electron transport activity of PSII reaction center, and inducing the increase of Rubisco activity to enhance carbon assimilation under the salt and low-temperature dual stress.


Assuntos
Plântula , Silício , Plântula/fisiologia , Silício/farmacologia , Temperatura , Clorofila A , Ribulose-Bifosfato Carboxilase , Dióxido de Silício/farmacologia , Fotossíntese , Clorofila , Cloreto de Sódio/farmacologia , Folhas de Planta/fisiologia
19.
Vaccine ; 41(42): 6339-6349, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37741761

RESUMO

OBJECTIVE: This study reports the vaccine effectiveness (VE) of COVID-19 vaccine regimens in the United States, based on the National COVID Cohort Collaborative (N3C) database. METHODS: Data from 10.4 million adults, enrolled in the N3C from 11 December 2020 to 30 June 2022, were analyzed. VE against infection and death outcomes were evaluated across 13 vaccine regimens in recipient cohorts during the Pre-Delta, Delta, and Omicron periods. VE was estimated as (1-odds ratio) × 100% by multivariate logistic regression, using the unvaccinated cohort as reference. RESULTS: Natural immunity showed a highly protective effect (70.33%) against re-infection, but the mortality risk among the unvaccinated population was increased after re-infection; vaccination following infection reduced the risk of re-infection and death. mRNA-1273 full vaccination plus mRNA-1273 booster showed the highest anti-infection effectiveness (47.59%) (95% CI, 46.72-48.45) in the overall cohort. In the type 2 diabetes cohort, VE against infection was highest with BNT162b2 full vaccination plus mRNA-1273 booster (61.19%) (95% CI, 53.73-67.75). VE against death was also highest with BNT162b2 full vaccination plus mRNA-1273 booster (89.56%) (95% CI, 85.75-92.61). During the Pre-Delta period, all vaccination regimens showed an anti-infection effect; during the Delta period, only boosters, mixed vaccines, and Ad26.COV2.S vaccination exhibited an anti-infection effect; during the Omicron period, none of the vaccine regimens demonstrated an anti-infection effect. Irrespective of the variant period, even a single dose of mRNA vaccine offered protection against death, thus demonstrating survival benefit, even in the presence of infection or re-infection. Similar patterns were observed in patients with type 2 diabetes. CONCLUSIONS: Although the anti-infection effect declined as SARS-CoV-2 variants evolved, all COVID-19 mRNA vaccines had sustained effectiveness against death. Vaccination was crucial for preventing re-infection and reducing the risk of death following SARS-CoV-2 infection.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Vacinas contra COVID-19 , Vacina BNT162 , Vacina de mRNA-1273 contra 2019-nCoV , Ad26COVS1 , Reinfecção , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2
20.
Front Pharmacol ; 14: 1222044, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719858

RESUMO

Background: Whether nebulized polymyxin B should be used as an adjunctive therapy or substitution strategy to intravenous polymyxin B for the treatment of ventilator-associated pneumonia (VAP) remains controversial. This study's aim is to evaluate the efficacy and safety of different administration ways of polymyxin B in the treatment of ventilator-associated pneumonia caused by extensively drug-resistant Gram-negative bacteria(XDR-GNB). Methods: This retrospective cohort study enrolled ventilator-associated pneumonia patients caused by XDR-GNB treated with polymyxin B in the intensive care unit. Patients were categorized by the administration methods as intravenous (IV) group, inhaled (IH) group, and the intravenous combined with inhaled (IV + IH) group. Microbiological outcome and clinical outcome were compared in each group. The side effects were also explored. Results: A total of 111 patients were enrolled and there was no difference in demographic and clinical characteristics among the three groups. In terms of efficacy, clinical cure or improvement was achieved in 21 patients (55.3%) in the intravenous group, 19 patients (50%) in the IH group, and 20 patients (57.1%) in IV + IH group (p = 0.815). All three groups showed high success rates in microbiological eradication, as 29 patients with negative cultures after medication in inhaled group. Among all the patients who had negative bacterial cultures after polymyxin B, the inhaled group had significantly shorter clearance time than the intravenous group (p = 0.002), but with no significant difference in 28-day mortality. Compared with intravenous group, a trend towards a lower risk of acute kidney injury was observed in inhaled group (p = 0.025). Conclusion: From the perspective of minimal systemic renal toxicity, nebulized polymyxin B as a substitution strategy to intravenous polymyxin B for the treatment of ventilator-associated pneumonia caused by XDR-GNB is feasible.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...