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1.
Immunity ; 55(6): 1067-1081.e8, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35659337

RESUMEN

Immunoregulatory B cells impede antitumor immunity through unknown features and mechanisms. We report the existence of leucine-tRNA-synthase-2 (LARS2)-expressing B cell (LARS B) subset with a transforming growth factor-ß1 (TGF-ß1)-dominant regulatory feature in both mouse and human progressive colorectal cancer (CRC). Of note, LARS B cells exhibited a leucine nutrient preference and displayed active mitochondrial aminoacyl-tRNA biosynthesis. They were located outside the tertiary lymphoid structure and correlated with colorectal hyperplasia and shortened survival in CRC patients. A leucine diet induced LARS B cell generation, whereas LARS B cell deletion by Lars2 gene ablation or leucine blockage repressed CRC immunoevasion. Mechanistically, LARS2 programmed mitochondrial nicotinamide adenine dinucleotide (NAD+) regeneration and oxidative metabolism, thus determining the regulatory feature of LARS B cells in which the NAD-dependent protein deacetylase sirtuin-1 (SIRT1) was involved. We propose a leucine-dieting scheme to inhibit LARS B cells, which is safe and useful for CRC therapy.


Asunto(s)
Aminoacil-ARNt Sintetasas , Neoplasias Colorrectales , Animales , Humanos , Leucina , Ratones , Mitocondrias/metabolismo , NAD/metabolismo , ARN de Transferencia
2.
Nature ; 599(7884): 290-295, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34671164

RESUMEN

Mouse caspase-11 and human caspase-4 and caspase-5 recognize cytosolic lipopolysaccharide (LPS) to induce pyroptosis by cleaving the pore-forming protein GSDMD1-5. This non-canonical inflammasome defends against Gram-negative bacteria6,7. Shigella flexneri, which causes bacillary dysentery, lives freely within the host cytosol where these caspases reside. However, the role of caspase-11-mediated pyroptosis in S. flexneri infection is unknown. Here we show that caspase-11 did not protect mice from S. flexneri infection, in contrast to infection with another cytosolic bacterium, Burkholderia thailandensis8. S. flexneri evaded pyroptosis mediated by caspase-11 or caspase 4 (hereafter referred to as caspase-11/4) using a type III secretion system (T3SS) effector, OspC3. OspC3, but not its paralogues OspC1 and 2, covalently modified caspase-11/4; although it used the NAD+ donor, this modification was not ADP-ribosylation. Biochemical dissections uncovered an ADP-riboxanation modification on Arg314 and Arg310 in caspase-4 and caspase-11, respectively. The enzymatic activity was shared by OspC1 and 2, whose ankyrin-repeat domains, unlike that of OspC3, could not recognize caspase-11/4. ADP-riboxanation of the arginine blocked autoprocessing of caspase-4/11 as well as their recognition and cleavage of GSDMD. ADP-riboxanation of caspase-11 paralysed pyroptosis-mediated defence in Shigella-infected mice and mutation of ospC3 stimulated caspase-11- and GSDMD-dependent anti-Shigella humoral immunity, generating a vaccine-like protective effect. Our study establishes ADP-riboxanation of arginine as a bacterial virulence mechanism that prevents LPS-induced pyroptosis.


Asunto(s)
Adenosina Difosfato Ribosa/metabolismo , Arginina/metabolismo , Proteínas Bacterianas/metabolismo , Caspasas Iniciadoras/metabolismo , Evasión Inmune , Piroptosis , Shigella flexneri/patogenicidad , Adenosina Difosfato/metabolismo , Animales , Disentería Bacilar/inmunología , Disentería Bacilar/microbiología , Femenino , Inmunidad Humoral , Inflamasomas/metabolismo , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , NAD/metabolismo , Piroptosis/efectos de los fármacos , Vacunas contra la Shigella , Shigella flexneri/inmunología , Virulencia
4.
Proc Natl Acad Sci U S A ; 120(39): e2305883120, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37725637

RESUMEN

Inspired by the development of single-atom catalysts (SACs), the fabrication of multimetallic SACs can be a promising technical approach for the in situ electro-Fenton (EF) process. Herein, dual-functional atomically dispersed Mo-Fe sites embedded in carbon nitride (C3N5) (i.e., MoFe/C3N5) were synthesized via a facile SiO2 template method. The atomically isolated bimetallic configuration in MoFe/C3N5 was identified by combining the microscopic and spectroscopic techniques. The MoFe/C3N5 catalyst on the cathode exhibited a remarkable catalytic activity toward the three electron-dominated oxygen reduction reaction in sodium sulfate, leading to a highly effective EF reaction with a low overpotential for the removal of organic contaminants from wastewater. The new catalyst showed a superior performance over its conventional counterparts, owing to the dual functions of the dual-metal active sites. Density functional theory (DFT) analysis revealed that the dual-functional 50-MoFe/C3N5 catalyst enabled a synergistic action of the Mo-Fe dual single atomic centers, which can alter the adsorption/dissociation behavior and decrease the overall reaction barriers for effective organic oxidation during the EF process. This study not only sheds light on the controlled synthesis of atomically isolated catalyst materials but also provides deeper understanding of the structure-performance relationship of the nanocatalysts with dual active sites for the catalytic EF process. Additionally, the findings will promote the advanced catalysis for the treatment of emerging organic contaminants in water and wastewater.

5.
Hum Mol Genet ; 32(15): 2502-2510, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37216648

RESUMEN

Limb-girdle muscular dystrophy R7 (LGMDR7) is an autosomal recessive hereditary muscular dystrophy caused by mutations in titin-cap (TCAP). Here, we summarized the clinical characteristics and TCAP mutations in a Chinese cohort of 30 patients with LGMDR7. The onset age of Chinese patients was 19.89 ± 6.70 years old, which is later than European and South Asian patients (P < 0.05). Clinically speaking, 20.0% of patients presented with predominant distal weakness, and 73.3% of patients presented with predominant pelvic girdle weakness. Radiological study revealed semitendinosus and magnus adductor were severely involved in Chinese LGMDR7 patients. Rectus femoris, vastus lateralis, vastus intermedius, soleus and tibialis anterior were moderately to severely involved. The most prevalent mutation in this cohort is c.26_33dupAGGTGTCG, while c.165dupG and c.110 + 5G > A are unique in Chinese population as two of the common mutations. Besides, variant c.26_33dupAGGGTGTCG might be a founder mutation in Asian patients. Internal nuclei, lobulated fibers, and scattered rimmed vacuoles were typical morphological changes in Chinese LGMDR7 patients. This is the largest LGMDR7 cohort in the Chinese population and in the world. This article also expands the clinical, pathological, mutational and radiological spectrum of patients with LGMDR7 in China and in the world.


Asunto(s)
Pueblos del Este de Asia , Distrofia Muscular de Cinturas , Adolescente , Adulto , Humanos , Adulto Joven , Músculo Esquelético/patología , Distrofia Muscular de Cinturas/genética , Distrofia Muscular de Cinturas/patología , Mutación
6.
Plant Physiol ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331524

RESUMEN

Salt stress impairs plant growth and development, generally resulting in crop failure. Tomato domestication gave rise to a dramatic decrease in salt tolerance caused by the genetic variability of the wild ancestors. However, the nature of artificial selection in reducing tomato salt tolerance remains unclear. Here, we generated and analyzed datasets on the survival rates and sodium (Na+) and potassium (K+) concentrations of hundreds of tomato varieties from wild ancestors to contemporary breeding accessions under high salinity. Genome-wide association studies (GWAS) revealed that natural variation in the promoter region of the putative K+ channel regulatory subunit-encoding gene KSB1 (potassium channel beta subunit in Solanum lycopersicum) is associated with survival rates and root Na+/K+ ratios in tomato under salt stress. This variation is deposited in tomato domestication sweeps and contributes to modified expression of KSB1 by salt-induced transcription factor SlHY5 in response to high salinity. We further found that KSB1 interacts with the K+ channel protein KSL1 to maintain cellular Na+ and K+ homeostasis, thus enhancing salt tolerance in tomato. Our findings reveal the crucial role of the SlHY5-KSB1-KSL1 module in regulating ion homeostasis and salt tolerance during tomato domestication, elucidating that selective pressure imposed by humans on the evolutionary process provides insights into further crop improvement.

7.
FASEB J ; 38(1): e23312, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38161282

RESUMEN

ProBDNF is the precursor protein of brain-derived neurotrophic factor (BDNF) expressed in the central nervous system and peripheral tissues. Previous studies showed that the blood levels of both proBDNF and p75 neurotrophic receptors (p75NTR) in major depressive disorder (MDD) were increased, but which blood cell types express proBDNF and its receptors is not known. Furthermore, the relationship between proBDNF/p75NTR and inflammatory cytokines in peripheral blood of MDD is unclear. Peripheral blood mononuclear cells (PBMCs) and serum were obtained from depressive patients (n = 32) and normal donors (n = 20). We examined the expression of proBDNF and inflammatory markers and their correlative relationship in patients with major depression. Using flow cytometry analysis, we examined which blood cells express proBDNF and its receptors. Finally, the role of proBDNF/p75NTR signal in inflammatory immune activity of PBMCs was verified in vitro experiments. Inflammatory cytokines in PBMC from MDD patients were increased and correlated with the major depression scores. The levels of IL-1ß and IL-10 were also positively correlated with the major depression scores, while the levels of TNF-α and IL-6 were negatively correlated with the major depression scores. Intriguingly, the levels of sortilin were positively correlated with IL-1ß. Q-PCR and Western blots showed proBDNF, p75NTR, and sortilin levels were significantly increased in PBMCs from MDD patients compared with that from the normal donors. Flow cytometry studies showed that proBDNF and p75NTR were present mainly in CD4+ and CD8+ T cells. The number of proBDNF and p75NTR positive CD4+ and CD8+ T cells from MDD patients was increased and subsequently reversed after therapeutic management. Exogenous proBDNF protein or p75ECD-Fc treatment of cultured PBMC affected the release of inflammatory cytokines in vitro. ProBDNF promoted the expression of inflammatory cytokines, while p75ECD-Fc inhibited the expression of inflammatory cytokines. Given there was an inflammatory response of lymphocytes to proBDNF, it is suggested that proBDNF/p75NTR signaling may upstream inflammatory cytokines in MDD. Our data suggest that proBDNF/p75NTR signaling may not only serve as biomarkers but also may be a potential therapeutic target for MDD.


Asunto(s)
Trastorno Depresivo Mayor , Humanos , Trastorno Depresivo Mayor/metabolismo , Leucocitos Mononucleares/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Receptores de Factor de Crecimiento Nervioso/metabolismo , Regulación hacia Arriba , Linfocitos T CD8-positivos/metabolismo , Depresión , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Citocinas/metabolismo
8.
J Med Genet ; 61(11): 1053-1061, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39332896

RESUMEN

BACKGROUND: GlcNAc2-epimerase (GNE) myopathy is a rare autosomal recessive disorder caused by pathogenic variants in the GNE gene, which is essential for the sialic acid biosynthesis pathway. OBJECTIVE: This multi-centre study aimed to delineate the clinical phenotype and GNE variant spectrum in Chinese patients, enhancing our understanding of the genetic diversity and clinical manifestation across different populations. METHODS: We retrospectively analysed GNE variants from 113 patients, integrating these data with external GNE variants from online databases for a global perspective, examining their consequences, distribution, ethnicity and severity. RESULTS: This study revealed 97 distinct GNE variants, including 35 (36.08%) novel variants. Two more patients with deep intronic variant c.862+870C>T were identified, while whole genome sequencing (WGS) uncovered another two novel intronic variants: c.52-8924G>T and c.1505-12G>A. Nanopore long reads sequencing (LRS) and further PCR analysis verified a 639 bp insertion at chr9:36249241. Missense variants predominantly located in the epimerase/kinase domain coding region, indicating the impairment of catalytic function as a key pathogenic consequence. Comparative studies with Japanese, Korean and Jewish, our cohorts showed later onset ages by 2 years. The high allele frequency of the non-catalytic GNE variant, c.620A>T, might underlie the milder phenotype of Chinese patients. CONCLUSIONS: Comprehensive techniques such as WGS and Nanopore LRS warrants the identifying of GNE variants. Patients with the non-catalytic GNE variant, c.620A>T, had a milder disease progression and later wheelchair use.


Asunto(s)
Estudios de Asociación Genética , Humanos , Masculino , Femenino , China/epidemiología , Estudios de Asociación Genética/métodos , Adulto , Niño , Adolescente , Fenotipo , Adulto Joven , Estudios Retrospectivos , Miopatías Distales/genética , Miopatías Distales/patología , Miopatías Distales/epidemiología , Mutación/genética , Preescolar , Carbohidrato Epimerasas/genética , Pueblo Asiatico/genética , Secuenciación Completa del Genoma , Complejos Multienzimáticos
9.
Drug Resist Updat ; 72: 101031, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38071860

RESUMEN

Carbapenem-resistant Escherichia coli (CREC) has become a major public health problem worldwide. To date, there is a limited understanding of the global distribution of CREC. In this study, we performed a comprehensive genomic analysis of 7, 731 CRECs of human origin collected from different countries worldwide between 2005 and 2023. Our results showed that these CRECs were distributed in 75 countries, mainly from the United States (17.49%), China (14.88%), and the United Kingdom (14.73%). Eight carbapenemases were identified among the CRECs analyzed, including KPC, IMP, NDM, VIM, OXA, FRI, GES, and IMI. NDM was the most predominant carbapenemase (52.15%), followed by OXA (30.09%) and KPC (14.72%). Notably, all CRECs carried multiple antibiotic resistance genes (ARGs), with 178 isolates carrying mcr-1 and 9 isolates carrying tet(X). The CREC isolates were classified into 465 known sequence types (STs), with ST167 being the most common (11.5%). Correlation analysis demonstrated the significant role of mobile genetic elements in facilitating the transfer of carbapenem resistance genes. Furthermore, some CRECs from different countries showed high genetic similarity, suggesting clonal transmission exists. According to the GWAS results, the genetic difference of blaNDM-positive CRECs from China were mainly enriched in bacterial Type IV secretion system pathways compared with those from the United Kingdom and the United States. Therefore, continuous global surveillance of CRECs is imperative in the future.


Asunto(s)
Proteínas Bacterianas , Enterobacteriaceae Resistentes a los Carbapenémicos , Humanos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Escherichia coli/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Genómica , Pruebas de Sensibilidad Microbiana
10.
J Infect Dis ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39171916

RESUMEN

BTB and CNC homology 1 (BACH1) plays a crucial role in the pathogenesis of acute lung injury (ALI) caused by gram-negative bacteria. However, its exact mechanisms and roles in Staphylococcus aureus (SA)-induced ALI, a gram-positive bacterial infection, remain incompletely understood. In this study, we generated a BACH1-knockout mouse model (BACH1-/-) to investigate the role of BACH1 and its underlying mechanisms in regulating the development of sepsis-induced acute lung injury (ALI). Elevated levels of BACH1 were observed in both serum samples from septic patients and mouse models. Deletion of BACH1 alleviated ALI symptoms induced by sepsis. In bone marrow-derived macrophages, BACH1 deletion or knockdown suppressed NF-κB p65 phosphorylation and the induction of pro-inflammatory cytokines. Mechanistic studies demonstrated that BACH1 downregulated tumor necrosis factor-alpha-induced protein 3 (TNFAIP3) mRNA expression by binding to its promoter region. These findings uncover inhibiting BACH1 may be a promising therapeutic strategy for treating gram-positive bacteria-induced ALI.

11.
J Cell Mol Med ; 28(2): e18048, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37986543

RESUMEN

Intervertebral disc degeneration (IVDD) is a common chronic musculoskeletal disease that causes chronic low back pain and imposes an immense financial strain on patients. The pathological mechanisms underlying IVDD have not been fully elucidated. The development of IVDD is closely associated with abnormal epigenetic changes, suggesting that IVDD progression may be controlled by epigenetic mechanisms. Consequently, this study aimed to investigate the role of epigenetic regulation, including DNA methyltransferase 3a (DNMT3a)-mediated methylation and peroxisome proliferator-activated receptor γ (PPARγ) inhibition, in IVDD development. The expression of DNMT3a and PPARγ in early and late IVDD of nucleus pulposus (NP) tissues was detected using immunohistochemistry and western blotting analyses. Cellularly, DNMT3a inhibition significantly inhibited IL-1ß-induced apoptosis and extracellular matrix (ECM) degradation in rat NP cells. Pretreatment with T0070907, a specific inhibitor of PPARγ, significantly reversed the anti-apoptotic and ECM degradation effects of DNMT3a inhibition. Mechanistically, DNMT3a modified PPARγ promoter hypermethylation to activate the nuclear factor-κB (NF-κB) pathway. DNMT3a inhibition alleviated IVDD progression. Conclusively, the results of this study show that DNMT3a activates the NF-κB pathway by modifying PPARγ promoter hypermethylation to promote apoptosis and ECM degradation. Therefore, we believe that the ability of DNMT3a to mediate the PPARγ/NF-κB axis may provide new ideas for the potential pathogenesis of IVDD and may become an attractive target for the treatment of IVDD.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Animales , Humanos , Ratas , ADN Metiltransferasa 3A , Epigénesis Genética , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/patología , Metilación , FN-kappa B/metabolismo , Núcleo Pulposo/patología , PPAR gamma/genética , PPAR gamma/metabolismo , Ratas Sprague-Dawley , Transducción de Señal
12.
Circulation ; 147(18): 1369-1381, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36870065

RESUMEN

BACKGROUND: Computed tomography-derived fractional flow reserve (CT-FFR) using on-site machine learning enables identification of both the presence of coronary artery disease and vessel-specific ischemia. However, it is unclear whether on-site CT-FFR improves clinical or economic outcomes when compared with the standard of care in patients with stable coronary artery disease. METHODS: In total, 1216 patients with stable coronary artery disease and an intermediate stenosis of 30% to 90% on coronary computed tomographic angiography were randomized to an on-site CT-FFR care pathway using machine learning or to standard care in 6 Chinese medical centers. The primary end point was the proportion of patients undergoing invasive coronary angiography without obstructive coronary artery disease or with obstructive disease who did not undergo intervention within 90 days. Secondary end points included major adverse cardiovascular events, quality of life, symptoms of angina, and medical expenditure at 1 year. RESULTS: Baseline characteristics were similar in both groups, with 72.4% (881/1216) having either typical or atypical anginal symptoms. A total of 421 of 608 patients (69.2%) in the CT-FFR care group and 483 of 608 patients (79.4%) in the standard care group underwent invasive coronary angiography. Compared with standard care, the proportion of patients undergoing invasive coronary angiography without obstructive coronary artery disease or with obstructive disease not undergoing intervention was significantly reduced in the CT-FFR care group (28.3% [119/421] versus 46.2% [223/483]; P<0.001). Overall, more patients underwent revascularization in the CT-FFR care group than in the standard care group (49.7% [302/608] versus 42.8% [260/608]; P=0.02), but major adverse cardiovascular events at 1 year did not differ (hazard ratio, 0.88 [95% CI, 0.59-1.30]). Quality of life and symptoms improved similarly during follow-up in both groups, and there was a trend towards lower costs in the CT-FFR care group (difference, -¥4233 [95% CI, -¥8165 to ¥973]; P=0.07). CONCLUSIONS: On-site CT-FFR using machine learning reduced the proportion of patients with stable coronary artery disease undergoing invasive coronary angiography without obstructive disease or requiring intervention within 90 days, but increased revascularization overall without improving symptoms or quality of life, or reducing major adverse cardiovascular events. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03901326.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico , Calidad de Vida , Angiografía Coronaria/métodos , Tomografía Computarizada por Rayos X , Angiografía por Tomografía Computarizada/métodos , Angina de Pecho , Valor Predictivo de las Pruebas
13.
BMC Genomics ; 25(1): 675, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977976

RESUMEN

BACKGROUND: The number of spikelets per spike is a key trait that affects the yield of bread wheat (Triticum aestivum L.). Identification of the QTL for spikelets per spike and its genetic effects that could be used in molecular assistant breeding in the future. RESULTS: In this study, four recombinant inbred line (RIL) populations were generated and used, having YuPi branching wheat (YP), with Supernumerary Spikelets (SS) phenotype, as a common parent. QTL (QSS.sicau-2 A and QSS.sicau-2D) related to SS trait were mapped on chromosomes 2 A and 2D through bulked segregant exome sequencing (BSE-Seq). Fourteen molecular markers were further developed within the localization interval, and QSS.sicau-2 A was narrowed to 3.0 cM covering 7.6 Mb physical region of the reference genome, explaining 13.7 - 15.9% the phenotypic variance. Similarly, the QSS.sicau-2D was narrowed to 1.8 cM covering 2.4 Mb physical region of the reference genome, and it explained 27.4 - 32.9% the phenotypic variance. These two QTL were validated in three different genetic backgrounds using the linked markers. QSS.sicau-2 A was identified as WFZP-A, and QSS.sicau-2D was identified a novel locus, different to the previously identified WFZP-D. Based on the gene expression patterns, gene annotation and sequence analysis, TraesCS2D03G0260700 was predicted to be a potential candidate gene for QSS.sicau-2D. CONCLUSION: Two significant QTL for SS, namely QSS.sicau-2 A and QSS.sicau-2D were identified in multiple environments were identified and their effect in diverse genetic populations was assessed. QSS.sicau-2D is a novel QTL associated with the SS trait, with TraesCS2D03G0260700 predicted as its candidate gene.


Asunto(s)
Mapeo Cromosómico , Fenotipo , Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Cromosomas de las Plantas/genética , Estudios de Asociación Genética , Genes de Plantas
14.
Immunology ; 173(2): 339-359, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38934051

RESUMEN

Maintaining intracellular redox balance is essential for the survival, antibody secretion, and mucosal immune homeostasis of immunoglobulin A (IgA) antibody-secreting cells (ASCs). However, the relationship between mitochondrial metabolic enzymes and the redox balance in ASCs has yet to be comprehensively studied. Our study unveils the pivotal role of mitochondrial enzyme PCK2 in regulating ASCs' redox balance and intestinal homeostasis. We discover that PCK2 loss, whether globally or in B cells, exacerbates dextran sodium sulphate (DSS)-induced colitis due to increased IgA ASC cell death and diminished antibody production. Mechanistically, the absence of PCK2 diverts glutamine into the TCA cycle, leading to heightened TCA flux and excessive mitochondrial reactive oxygen species (mtROS) production. In addition, PCK2 loss reduces glutamine availability for glutathione (GSH) synthesis, resulting in a decrease of total glutathione level. The elevated mtROS and reduced GSH expose ASCs to overwhelming oxidative stress, culminating in cell apoptosis. Crucially, we found that the mitochondria-targeted antioxidant Mitoquinone (Mito-Q) can mitigate the detrimental effects of PCK2 deficiency in IgA ASCs, thereby alleviating colitis in mice. Our findings highlight PCK2 as a key player in IgA ASC survival and provide a potential new target for colitis treatment.


Asunto(s)
Colitis , Homeostasis , Mitocondrias , Estrés Oxidativo , Animales , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/inmunología , Ratones , Mitocondrias/metabolismo , Inmunoglobulina A/metabolismo , Sulfato de Dextran , Ratones Noqueados , Células Productoras de Anticuerpos/inmunología , Células Productoras de Anticuerpos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ratones Endogámicos C57BL , Glutatión/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/inmunología , Intestinos/inmunología , Apoptosis , Modelos Animales de Enfermedad
15.
J Am Chem Soc ; 146(29): 20107-20115, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38842422

RESUMEN

Photocatalytic covalent organic frameworks (COFs) are typically constructed with rigid aromatic linkers for crystallinity and extended π-conjugation. However, the essential hydrophobicity of the aromatic backbone can limit their performances in water-based photocatalytic reactions. Here, we for the first time report the synthesis of hydrophilic COFs with aliphatic linkers [tartaric acid dihydrazide (TAH) and butanedioic acid dihydrazide] that can function as efficient photocatalysts for H2O2 and H2 evolution. In these hydrophilic aliphatic linkers, the specific multiple hydrogen bonding networks not only enhance crystallization but also ensure an ideal compatibility of crystallinity, hydrophilicity, and light harvesting. The resulting aliphatic linker COFs adopt an unusual ABC stacking, giving rise to approximately 0.6 nm nanopores with an improved interaction with water guests. Remarkably, both aliphatic linker-based COFs show strong visible light absorption, along with a narrow optical band gap of ∼1.9 eV. The H2O2 evolution rate for TAH-COF reaches up to 6003 µmol h-1 g-1, in the absence of sacrificial agents, surpassing the performance of all previously reported COF-based photocatalysts. Theoretical calculations reveal that the TAH linker can enhance the indirect two-electron oxygen reduction reaction for H2O2 production by improving the O2 adsorption and stabilizing the *OOH intermediate. This study opens a new avenue for constructing semiconducting COFs using nonaromatic linkers.

16.
PLoS Med ; 21(5): e1004389, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38728364

RESUMEN

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Camptotecina , Cetuximab , Neoplasias Colorrectales , Fluorouracilo , Leucovorina , Neoplasias Hepáticas , Compuestos Organoplatinos , Proteínas Proto-Oncogénicas B-raf , Humanos , Cetuximab/administración & dosificación , Cetuximab/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Masculino , Persona de Mediana Edad , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/tratamiento farmacológico , Femenino , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Leucovorina/uso terapéutico , Leucovorina/administración & dosificación , Fluorouracilo/uso terapéutico , Fluorouracilo/administración & dosificación , Compuestos Organoplatinos/uso terapéutico , Compuestos Organoplatinos/administración & dosificación , Proteínas Proto-Oncogénicas B-raf/genética , Anciano , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Camptotecina/administración & dosificación , Resultado del Tratamiento , Proteínas ras/genética
17.
Cancer Sci ; 115(4): 1209-1223, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38288904

RESUMEN

Abnormal activation of the oncogene YAP in the Hippo pathway is a major feature in liver cancer and inactivation of MST1/2 has been shown to be responsible for the overactivation of YAP that led to tumorigenesis. However, mechanisms underlying MST1/2 dysregulation remain poorly understood. RNA-seq analysis and genome (KEGG) pathway enrichment analysis were used to identify genes and pathways that were regulated by SIRT7. qRT-PCR, ChIP, and luciferase assay were used to investigate transcriptional regulation. Mass spectrometry, co-immunoprecipitation and immunoprecipitation were used to exam protein-protein interaction and post-transcriptional modification. A xenograft mouse model was used to confirm the effect of SIRT7 and SIRT7 inhibitors on hepatocellular carcinoma (HCC) proliferation in vivo. We found that SIRT7 suppresses MST1 by both transcriptional regulation and post-transcriptional modification, which in turn promotes YAP nuclear localization and transcriptional activation in liver cancer. Mechanistically, we revealed that SIRT7 suppresses MST1 transcription by binding to the MST1 promoter and inducing H3K18 deacetylation in its promoter region. In addition, SIRT7 directly binds to and deacetylates MST1, which primes acetylation-dependent MST1 ubiquitination and protein degradation. In clinical samples, we confirmed a negative correlation between SIRT7 and MST1 protein levels, and high SIRT7 expression correlated with elevated YAP expression and nuclear localization. In addition, SIRT7 specific inhibitor 2800Z sufficiently inhibited HCC growth by disrupting the SIRT7/MST1/YAP axis. Our data thus revealed the previously undescribed function of SIRT7 in regulating the Hippo pathway in HCC and further proved that targeting SIRT7 might provide novel therapeutic options for the treatment of liver cancer.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sirtuinas , Humanos , Ratones , Animales , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Transducción de Señal , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proliferación Celular/genética , Sirtuinas/genética , Sirtuinas/metabolismo
18.
Antimicrob Agents Chemother ; 68(4): e0126123, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38415983

RESUMEN

Antibiotic resistance represents a significant challenge to public health and human safety. The primary driver behind the dissemination of antibiotic resistance is the horizontal transfer of plasmids. Current conjugative transfer assay is generally performed in a standardized manner, ignoring the effect of the host environment. Host defense peptides (HDPs) possess a wide range of biological targets and play an essential role in the innate immune system. Herein, we reveal that sub-minimum inhibitory concentrations of HDPs facilitate the conjugative transfer of RP4-7 plasmid in the Luria Broth medium, and this observation is reversed in the RPMI medium, designed to simulate the host environment. Out of these HDPs, indolicidin (Ind), a cationic tridecapeptide from bovine neutrophils, significantly inhibits the conjugation of multidrug resistance plasmids in a dose-dependent manner, including blaNDM- and tet(X4)-bearing plasmids. We demonstrate that the addition of Ind to RPMI medium as the incubation substrate downregulates the expression of conjugation-related genes. In addition, Ind weakens the tricarboxylic acid cycle, impedes the electron transport chain, and disrupts the proton motive force, consequently diminishing the synthesis of adenosine triphosphate and limiting the energy supply. Our findings highlight the importance of the host-like environments for the development of horizontal transfer inhibitors and demonstrate the potential of HDPs in preventing the spread of resistance plasmids.


Asunto(s)
Conjugación Genética , Genes Bacterianos , Animales , Bovinos , Humanos , Plásmidos/genética , Farmacorresistencia Microbiana , Transferencia de Gen Horizontal , Péptidos Catiónicos Antimicrobianos/farmacología , Antibacterianos/farmacología
19.
Lancet ; 401(10380): 917-927, 2023 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-36842439

RESUMEN

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.


Asunto(s)
Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Masculino , Humanos , Femenino , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Recurrencia Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Hemorragia
20.
Oncologist ; 29(8): e1012-e1019, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38642091

RESUMEN

INTRODUCTION: Fruquintinib is approved in China for patients with metastatic colorectal cancer (CRC) who progressed after 2 lines of chemotherapy. This postmarketing study was conducted to evaluate the safety of fruquintinib in the Chinese population, including previously treated patients with advanced CRC and other solid tumors. METHODS: Patients in the first cycle of fruquintinib or expected to start fruquintinib within a week were enrolled. Fruquintinib was administrated according to the label or per physicians' discretion. Patient characteristics and safety information were collected at baseline, 1 month, and 6 months after consent (or 30 days after the last dose). RESULTS: Overall, 3005 patients enrolled between April 24, 2019 and September 27, 2022. All enrolled patients received at least one dose of fruquintinib. Most patients had metastases at baseline. The median age was 60 years. More than half (64.0%) of the patients started fruquintinib at 5 mg, and the median treatment exposure was 2.7 months. Nearly one-third (32.5%) of patients with CRC received fruquintinib with concomitant antineoplastic agents. Treatment-emergent adverse events (TEAEs) leading to dose modification were reported in 626 (20.8%) patients, and 469 (15.6%) patients experienced TEAEs leading to treatment discontinuation. The most common grade ≥ 3 TEAEs were hypertension (6.6%), palmar-plantar erythrodysesthesia syndrome (2.2%), and platelet count decreased (1.0%). Combination therapy did not lead to excessive toxicities. CONCLUSIONS: The safety profile of fruquintinib in the real world was generally consistent with that in clinical studies, and the incidence of TEAEs was numerically lower than known VEGF/VEGFR inhibitor-related AEs. Fruquintinib exhibited manageable safety and tolerability in Chinese patients in the real-world setting.


Asunto(s)
Benzofuranos , Neoplasias Colorrectales , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Benzofuranos/efectos adversos , Benzofuranos/uso terapéutico , Benzofuranos/administración & dosificación , Adulto , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Quinazolinas/efectos adversos , Quinazolinas/uso terapéutico , Quinazolinas/administración & dosificación , China , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Antineoplásicos/administración & dosificación , Pueblos del Este de Asia
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