Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 238
Filtrar
1.
Chem Commun (Camb) ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38845542

RESUMEN

In this study, a Rh(III)-catalyzed C-H/N-H [4+2] annulation of oxadiazolones with iodonium ylides has been developed, which afforded a series of diverse fused-isoquinolines and fused-pyridines in moderate to high yields. These divergent synthesis protocols featured mild conditions, broad substrate scope, and functional-group compatibility. In addition, scale-up synthesis, related applications and preliminary mechanistic explorations were also accomplished.

2.
Mol Cell ; 84(11): 2009-2010, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38848688

RESUMEN

In this issue, Diamond et al.1 and Kim et al.2 report that depletion of eIF4E leads to translational upregulation of GCN4, a key player in the integrated stress response, in an eIF2α phosphorylation-independent manner, suggesting a new mode of translational adaptation.


Asunto(s)
Factor 4E Eucariótico de Iniciación , Estrés Fisiológico , Factor 4E Eucariótico de Iniciación/metabolismo , Factor 4E Eucariótico de Iniciación/genética , Fosforilación , Humanos , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 2 Eucariótico de Iniciación/genética , Biosíntesis de Proteínas , Animales , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
3.
J Orthop Surg Res ; 19(1): 309, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783358

RESUMEN

BACKGROUND: Elderly patients suffering from osteoporotic fractures are more susceptible to delayed union or nonunion, and their bodies then are in a state of low-grade chronic inflammation with decreased antioxidant capacity. Tanshinone IIA is widely used in treating cardiovascular and cerebrovascular diseases in China and has anti-inflammatory and antioxidant effects. We aimed to observe the antioxidant effects of Tanshinone IIA on mesenchymal stem cells (MSCs), which play important roles in bone repair, and the effects of local application of Tanshinone IIA using an injectable biodegradable hydrogel on osteoporotic fracture healing. METHODS: MSCs were pretreated with or without different concentrations of Tanshinone IIA followed by H2O2 treatment. Ovariectomized (OVX) C57BL/6 mice received a mid-shaft transverse osteotomy fracture on the left tibia, and Tanshinone IIA was applied to the fracture site using an injectable hydrogel. RESULTS: Tanshinone IIA pretreatment promoted the expression of nuclear factor erythroid 2-related factor 2 and antioxidant enzymes, and inhibited H2O2-induced reactive oxygen species accumulation in MSCs. Furthermore, Tanshinone IIA reversed H2O2-induced apoptosis and decrease in osteogenic differentiation in MSCs. After 4 weeks of treatment with Tanshinone IIA in OVX mice, the bone mineral density of the callus was significantly increased and the biomechanical properties of the healed tibias were improved. Cell apoptosis was decreased and Nrf2 expression was increased in the early stage of callus formation. CONCLUSIONS: Taken together, these results indicate that Tanshinone IIA can activate antioxidant enzymes to protect MSCs from H2O2-induced cell apoptosis and osteogenic differentiation inhibition. Local application of Tanshinone IIA accelerates fracture healing in ovariectomized mice.


Asunto(s)
Abietanos , Apoptosis , Curación de Fractura , Células Madre Mesenquimatosas , Ratones Endogámicos C57BL , Ovariectomía , Animales , Abietanos/administración & dosificación , Abietanos/farmacología , Femenino , Células Madre Mesenquimatosas/efectos de los fármacos , Apoptosis/efectos de los fármacos , Curación de Fractura/efectos de los fármacos , Ratones , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Peróxido de Hidrógeno , Osteogénesis/efectos de los fármacos , Fracturas Osteoporóticas/prevención & control
4.
Brain Sci ; 14(4)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38671952

RESUMEN

Parkinson's disease (PD) is characterized not only by motor symptoms but also by non-motor dysfunctions, such as olfactory impairment; the cause is not fully understood. Our study suggests that neuronal loss and inflammation in brain regions along the olfactory pathway, such as the olfactory bulb (OB) and the piriform cortex (PC), may contribute to olfactory dysfunction in PD mice, which might be related to the downregulation of the trace amine-associated receptor 1 (TAAR1) in these areas. In the striatum, although only a decrease in mRNA level, but not in protein level, of TAAR1 was detected, bioinformatic analyses substantiated its correlation with PD. Moreover, we discovered that neuronal death and inflammation in the OB and the PC in PD mice might be regulated by TAAR through the Bcl-2/caspase3 pathway. This manifested as a decrease of anti-apoptotic protein Bcl-2 and an increase of the pro-apoptotic protein cleaved caspase3, or through regulating astrocytes activity, manifested as the increase of TAAR1 in astrocytes, which might lead to the decreased clearance of glutamate and consequent neurotoxicity. In summary, we have identified a possible mechanism to elucidate the olfactory dysfunction in PD, positing neuronal damage and inflammation due to apoptosis and astrocyte activity along the olfactory pathway in conjunction with the downregulation of TAAR1.

5.
Int Immunopharmacol ; 133: 112126, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38669946

RESUMEN

Type 17 helper T cells (Th17)-dominant neutrophilic airway inflammation is critical in the pathogenesis of steroid-resistant airway inflammation such as severe asthma. Small extracellular vesicles (sEV) derived from human mesenchymal stem cells (MSCs) display extensive therapeutic effects and advantages in many diseases. However, the role of MSC-sEV in Th17-dominant neutrophilic airway inflammation and the related mechanisms are still poorly studied. Here we found that MSC-sEV significantly alleviated the infiltration of inflammatory cells in peribronchial interstitial tissues and reduced levels of inflammatory cells, especially neutrophils, in bronchoalveolar lavage fluids (BALF) of mice with neutrophilic airway inflammation. Consistently, MSC-sEV significantly decreased levels of IL-17A in BALF and Th17 in lung tissues. Furthermore, we found that labelled MSC-sEV were taken up by human CD4+ T cells most obviously at 12 h after incubation, and distributed mostly in mouse lungs. More importantly, potential signaling pathways involved in the MSC-sEV mediated inhibition of Th17 polarization were found using RNA sequencing. Using Western blot, JAK2-STAT3 pathway was identified as an important role in the inhibition of Th17 polarization by MSC-sEV. We found that proteins in MSC-sEV were mostly involved in the therapeutic effects of MSC-sEV. In total, our study suggested that MSC-sEV could be a potential therapeutic strategy for the treatment of neutrophilic airway inflammation.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Neutrófilos , Factor de Transcripción STAT3 , Células Th17 , Células Th17/inmunología , Humanos , Animales , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/inmunología , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/metabolismo , Ratones , Neutrófilos/inmunología , Factor de Transcripción STAT3/metabolismo , Janus Quinasa 2/metabolismo , Interleucina-17/metabolismo , Pulmón/inmunología , Pulmón/patología , Ratones Endogámicos C57BL , Células Cultivadas , Líquido del Lavado Bronquioalveolar/inmunología , Líquido del Lavado Bronquioalveolar/citología , Asma/inmunología , Asma/terapia , Masculino , Transducción de Señal , Femenino , Modelos Animales de Enfermedad
6.
Cell Discov ; 10(1): 28, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38472169

RESUMEN

Due to a rapidly aging global population, osteoporosis and the associated risk of bone fractures have become a wide-spread public health problem. However, osteoporosis is very heterogeneous, and the existing standard diagnostic measure is not sufficient to accurately identify all patients at risk of osteoporotic fractures and to guide therapy. Here, we constructed the first prospective multi-omics atlas of the largest osteoporosis cohort to date (longitudinal data from 366 participants at three time points), and also implemented an explainable data-intensive analysis framework (DLSF: Deep Latent Space Fusion) for an omnigenic model based on a multi-modal approach that can capture the multi-modal molecular signatures (M3S) as explicit functional representations of hidden genotypes. Accordingly, through DLSF, we identified two subtypes of the osteoporosis population in Chinese individuals with corresponding molecular phenotypes, i.e., clinical intervention relevant subtypes (CISs), in which bone mineral density benefits response to calcium supplements in 2-year follow-up samples. Many snpGenes associated with these molecular phenotypes reveal diverse candidate biological mechanisms underlying osteoporosis, with xQTL preferences of osteoporosis and its subtypes indicating an omnigenic effect on different biological domains. Finally, these two subtypes were found to have different relevance to prior fracture and different fracture risk according to 4-year follow-up data. Thus, in clinical application, M3S could help us further develop improved diagnostic and treatment strategies for osteoporosis and identify a new composite index for fracture prediction, which were remarkably validated in an independent cohort (166 participants).

7.
Stem Cells Transl Med ; 13(5): 462-476, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38459853

RESUMEN

Adipose stem cell (ASC)-based therapies provide an encouraging option for tissue repair and regeneration. However, the function of these cells declines with aging, which limits their clinical transformation. Recent studies have outlined the involvement of long non-coding RNAs in stem cell aging. Here, we reanalyzed our published RNA sequencing (RNA-seq) data profiling differences between ASCs from young and old donors and identified a lncRNA named double homeobox A pseudogene 10 (DUXAP10) as significantly accumulated in aged ASCs. Knocking down DUXAP10 promoted stem cell proliferation and migration and halted cell senescence and the secretion of proinflammatory cytokines. In addition, DUXAP10 was located in the cytoplasm and functioned as a decoy for miR-214-3p. miR-214-3p was downregulated in aged ASCs, and its overexpression rejuvenated aged ASCs and reversed the harm caused by DUXAP10. Furthermore, Ras Association Domain Family Member 5 (RASSF5) was the target of miR-214-3p and was upregulated in aged ASCs. Overexpressing DUXAP10 and inhibiting miR-214-3p both enhanced RASSF5 content in ASCs, while DUXAP10 knockdown promoted the therapeutic ability of aged ASCs for skin wound healing. Overall, this study offers new insights into the mechanism of age-related ASC dysfunction and names DUXAP10 and miR-214-3p as potential targets for energizing aged stem cells.


Asunto(s)
Tejido Adiposo , MicroARNs , ARN Largo no Codificante , MicroARNs/metabolismo , MicroARNs/genética , Humanos , ARN Largo no Codificante/metabolismo , ARN Largo no Codificante/genética , Animales , Ratones , Tejido Adiposo/metabolismo , Tejido Adiposo/citología , Células Madre/metabolismo , Células Madre/citología , Senescencia Celular , Rejuvenecimiento/fisiología , Proliferación Celular , Técnicas de Silenciamiento del Gen
8.
Phytomedicine ; 126: 155073, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38417244

RESUMEN

BACKGROUND: Cervical spondylotic myelopathy (CSM) is a degenerative pathology that affects both upper and lower extremity mobility and sensory function, causing significant pressure on patients and society. Prior research has suggested that ginsenosides may have neuroprotective properties in central nervous system diseases. However, the efficacy and mechanism of ginsenosides for CSM have yet to be investigated. PURPOSE: This study aims to analyze the composition of ginsenosides using UPLC-MS, identify the underlying mechanism of ginsenosides in treating CSM using network pharmacology, and subsequently confirm the efficacy and mechanism of ginsenosides in rats with chronic spinal cord compression. METHODS: UPLC-Q-TOF-MS was utilized to obtain mass spectrum data of ginsenoside samples. The chemical constituents of the samples were analyzed by consulting literature reports and relevant databases. Ginsenoside and CSM targets were obtained from the TCMSP, OMIM, and GeneCards databases. GO and KEGG analyses were conducted, and a visualization network of ginsenosides-compounds-key targets-pathways-CSM was constructed, along with molecular docking of key bioactive compounds and targets, to identify the signaling pathways and proteins associated with the therapeutic effects of ginsenosides on CSM. Chronic spinal cord compression rats were intraperitoneally injected with ginsenosides (50 mg/kg and 150 mg/kg) and methylprednisolone for 28 days, and motor function was assessed to investigate the therapeutic efficacy of ginsenosides for CSM. The expression of proteins associated with TNF, IL-17, TLR4/MyD88/NF-κB, and NLRP3 signaling pathways was assessed by immunofluorescence staining and western blotting. RESULTS: Using UPLC-Q-TOF-MS, 37 compounds were identified from ginsenoside samples. Furthermore, ginsenosides-compounds-key targets-pathways-CSM visualization network indicated that ginsenosides may modulate the PI3K-Akt signaling pathway, TNF signaling pathway, MAPK signaling pathway, IL-17 signaling pathway, Toll-like receptor signaling pathway and Apoptosis by targeting AKT1, TNF, MAPK1, CASP3, IL6, and IL1B, exerting a therapeutic effect on CSM. By attenuating neuroinflammation through the TNF, IL-17, TLR4/MyD88/NF-κB, and MAPK signaling pathways, ginsenosides restored the motor function of rats with CSM, and ginsenosides 150 mg/kg showed better effect. This was achieved by reducing the phosphorylation of NF-κB and the activation of the NLRP3 inflammasome. CONCLUSIONS: The results of network pharmacology indicate that ginsenosides can inhibit neuroinflammation resulting from spinal cord compression through multiple pathways and targets. This finding was validated through in vivo tests, which demonstrated that ginsenosides can reduce neuroinflammation by inhibiting NLRP3 inflammasomes via multiple signaling pathways, additionally, it should be noted that 150 mg/kg was a relatively superior dose. This study is the first to verify the intrinsic molecular mechanism of ginsenosides in treating CSM by combining pharmacokinetics, network pharmacology, and animal experiments. The findings can provide evidence for subsequent clinical research and drug development.


Asunto(s)
Experimentación Animal , Medicamentos Herbarios Chinos , Ginsenósidos , Compresión de la Médula Espinal , Enfermedades de la Médula Espinal , Humanos , Animales , Ratas , Ginsenósidos/farmacología , Interleucina-17 , Proteína con Dominio Pirina 3 de la Familia NLR , FN-kappa B , Cromatografía Liquida , Simulación del Acoplamiento Molecular , Factor 88 de Diferenciación Mieloide , Farmacología en Red , Enfermedades Neuroinflamatorias , Fosfatidilinositol 3-Quinasas , Receptor Toll-Like 4 , Espectrometría de Masas en Tándem , Medicamentos Herbarios Chinos/farmacología
9.
Sci Adv ; 10(7): eadk1721, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363834

RESUMEN

Characterizing the tumor microenvironment at the molecular level is essential for understanding the mechanisms of tumorigenesis and evolution. However, the specificity of the blood proteome in localized region of the tumor and its linkages with other systems is difficult to investigate. Here, we propose a spatially multidimensional comparative proteomics strategy using glioma as an example. The blood proteome signature of tumor microenvironment was specifically identified by in situ collection of arterial and venous blood from the glioma region of the brain for comparison with peripheral blood. Also, by integrating with different dimensions of tissue and peripheral blood proteomics, the information on the genesis, migration, and exchange of glioma-associated proteins was revealed, which provided a powerful method for tumor mechanism research and biomarker discovery. The study recruited multidimensional clinical cohorts, allowing the proteomic results to corroborate each other, reliably revealing biological processes specific to gliomas, and identifying highly accurate biomarkers.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Proteómica/métodos , Neoplasias Encefálicas/patología , Proteoma/metabolismo , Glioma/patología , Biomarcadores , Microambiente Tumoral
10.
Nat Struct Mol Biol ; 30(11): 1816-1825, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37957305

RESUMEN

A translating ribosome is typically thought to follow the reading frame defined by the selected start codon. Using super-resolution ribosome profiling, here we report pervasive out-of-frame translation immediately from the start codon. Start codon-associated ribosomal frameshifting (SCARF) stems from the slippage of ribosomes during the transition from initiation to elongation. Using a massively paralleled reporter assay, we uncovered sequence elements acting as SCARF enhancers or repressors, implying that start codon recognition is coupled with reading frame fidelity. This finding explains thousands of mass spectrometry spectra that are unannotated in the human proteome. Mechanistically, we find that the eukaryotic initiation factor 5B (eIF5B) maintains the reading frame fidelity by stabilizing initiating ribosomes. Intriguingly, amino acid starvation induces SCARF by proteasomal degradation of eIF5B. The stress-induced SCARF protects cells from starvation by enabling amino acid recycling and selective mRNA translation. Our findings illustrate a beneficial effect of translational 'noise' in nutrient stress adaptation.


Asunto(s)
Sistema de Lectura Ribosómico , Proteínas de Saccharomyces cerevisiae , Humanos , Codón Iniciador/genética , Codón Iniciador/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Aminoácidos/genética , Aminoácidos/metabolismo , Biosíntesis de Proteínas
11.
Nat Cell Biol ; 25(11): 1562-1563, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37857832
12.
Huan Jing Ke Xue ; 44(9): 5308-5315, 2023 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-37699848

RESUMEN

The technology of carbon capture, utilization, and storage (CCUS) is an important component of carbon neutral technology systems. To confirm the carbon storage potential of CO2 foamed concrete (CFC), this study addressed the principle of carbon storage in CFC materials. It is apparent that carbon storage of CFC materials includes carbon fixation in concrete skeletons and carbon storage in CFC bubbles. The carbon fixation of CFC skeletons is realized by CO2 mineralization. As the concrete skeleton in CFC is in the CO2 atmosphere, the carbonation of CFC materials or CO2 mineralization is more complete. Research shows that the carbonation rate of CFC materials can reach almost 30% after acidification, foaming with high CO2 pressure and curing in the atmosphere. The carbonation rate is higher than the rate in concrete curing with CO2. A mathematical model was established to calculate carbon fixation capacity in CFC materials, and the carbon fixation and storage capacity in CFC material were estimated. The results showed that more than 99% carbon storage of CFC was realized by the chemical carbonization of the concrete skeleton. Comparatively, the potential of carbon storage in the bubble of CFC was small. In this study, carbon storage capacity was divided into three categories, i.e., theoretical maximum capacity, relative reliable capacity, and expected capacity or potential. The carbonation rate for theoretical maximum capacity was 100%, when all the concrete was considered to be carbonated. As the carbonation rate of concrete during the whole life cycle is approximately 55% all over the world, 50% was set as the carbonation rate for relative reliable capacity calculation. If at high temperatures, CO2 curing with high pressure or accessory ingredients applied to silicate concrete can improve carbonation rate to be over 80%, when the carbon storage capacity is considered to be expected capacity or potential. In 2017-2021, the theoretical maximum capacity of carbon storage was 3.623×109 t CO2 in China, with 7.25×108 t·a-1. The relative reliable capacity was 3.75×108 t·a-1, and the expected capacity was 5.80×108 t·a-1. If the carbonation rate was 30%, the carbon storage of concrete produced annually in China during the whole life cycle reached 2.18×108 t, which was more than the carbon sink of Daxing'anling forest for one year. In coal electricity integrated mining areas and large thermal, metallurgical, cement chemical, and other high-energy consuming enterprises, CFC has a good prospect of development to promote the recycling of solid waste and waste gas. Meanwhile, it is pointed out that the stability of CFC before solidification is a technical problem to be solved in the next step.

13.
Nutr Neurosci ; : 1-13, 2023 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-37691351

RESUMEN

CONTEXT: Spinal cord injury (SCI) is a potentially fatal neurological disease with severe complications and a high disability rate. An increasing number of animal experimental studies support the therapeutic effect of quercetin, which is a natural anti-inflammatory and antioxidant bioflavonoid. OBJECTIVE: This paper reviewed the therapeutic effect of quercetin on a rat SCI model and summarized the relevant mechanistic research. DATA SOURCES: PubMed, EMBASE, Web of Science, Science Direct, WanFang Data, SinoMed databases, the China National Knowledge Infrastructure, and the Vip Journal Integration Platform were searched from their inception to April 2023 for animal experiments applying quercetin to treat SCI. STUDY SELECTION: Based on the PICOS criteria, a total of 18 eligible studies were included, of which 14 were high quality. RESULTS: In this study, there was a gradual increase in effect based on the Basso, Beattie, and Bresnahan (BBB) score after three days (p < 0.0001). Furthermore, gender differences also appeared in the efficacy of quercetin; males performed better than females (p = 0.008). Quercetin was also associated with improved inclined plane test score (p = 0.008). In terms of biochemical indicators, meta-analysis showed that MDA (p < 0.0001) and MPO (p = 0.0002) were significantly reduced after quercetin administration compared with the control group, and SOD levels were increased (p = 0.004). Mechanistically, quercetin facilitates the inhibition of oxidative stress, inflammation, autophagy and apoptosis that occur after SCI. CONCLUSIONS: Generally, this systematic review suggests that quercetin has a neuroprotective effect on SCI.

14.
Calcif Tissue Int ; 113(5): 558-570, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37747519

RESUMEN

Monotropein is one of the active ingredients in Morinda Officinalis, which has been used for the treatment in multiple bone and joint diseases. This study aimed to observe the in vitro effects of Monotropein on osteogenic differentiation of lipopolysaccharide treated bone marrow mesenchymal stem cells (bMSCs), and the in vivo effects of local application of Monotropein on bone fracture healing in ovariectomized mice. Lipopolysaccharide was used to set up the inflammatory model in bMSCs, which were treated by Monotropein. Molecular docking analysis was performed to evaluate the potential interaction between Monotropein and p65. Transverse fractures of middle tibias were established in ovariectomized mice, and Monotropein was locally applied to the fracture site using injectable hydrogel. Monotropein enhanced the ability of primary bMSCs in chondro-osteogenic differentiation. Furthermore, Monotropein rescued lipopolysaccharide-induced osteogenic differentiation impairment and inhibited lipopolysaccharide-induced p65 phosphorylation in primary bMSCs. Docking analysis showed that the binding activity of Monotropein and p65/14-3-3 complex is stronger than the selective inhibitor of NF-κB (p65), DP-005. Local application of Monotropein partially rescued the decreased bone mass and biomechanical properties of callus or healed tibias in ovariectomized mice. The expressions of Runx2, Osterix and Collagen I in the 2-week callus were partially restored in Monotropein-treated ovariectomized mice. Taking together, local application of Monotropein promoted fracture healing in ovariectomized mice. Inhibition of p65 phosphorylation and enhancement in osteogenesis of mesenchymal stem cells could be partial of the effective mechanisms.


Asunto(s)
Curación de Fractura , Células Madre Mesenquimatosas , Ratones , Animales , Osteogénesis , Lipopolisacáridos/farmacología , Lipopolisacáridos/metabolismo , Simulación del Acoplamiento Molecular , Diferenciación Celular , Células Cultivadas , Células de la Médula Ósea
15.
Mol Cell ; 83(18): 3347-3359.e9, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37647899

RESUMEN

The amino acid cysteine and its oxidized dimeric form cystine are commonly believed to be synonymous in metabolic functions. Cyst(e)ine depletion not only induces amino acid response but also triggers ferroptosis, a non-apoptotic cell death. Here, we report that unlike general amino acid starvation, cyst(e)ine deprivation triggers ATF4 induction at the transcriptional level. Unexpectedly, it is the shortage of lysosomal cystine, but not the cytosolic cysteine, that elicits the adaptative ATF4 response. The lysosome-nucleus signaling pathway involves the aryl hydrocarbon receptor (AhR) that senses lysosomal cystine via the kynurenine pathway. A blockade of lysosomal cystine efflux attenuates ATF4 induction and sensitizes ferroptosis. To potentiate ferroptosis in cancer, we develop a synthetic mRNA reagent, CysRx, that converts cytosolic cysteine to lysosomal cystine. CysRx maximizes cancer cell ferroptosis and effectively suppresses tumor growth in vivo. Thus, intracellular nutrient reprogramming has the potential to induce selective ferroptosis in cancer without systematic starvation.


Asunto(s)
Quistes , Ferroptosis , Humanos , Cisteína , Cistina , Ferroptosis/genética , Aminoácidos , Lisosomas
16.
Eur J Clin Pharmacol ; 79(9): 1249-1259, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37449992

RESUMEN

PURPOSE: We aimed to explore the contribution of genotype-guided selection of P2Y12 inhibitors on prognosis in Chinese patients with acute coronary syndromes (ACS) or chronic coronary syndromes (CCS) undergoing percutaneous coronary intervention (PCI). METHODS: Totally, 2063 patients were included. They were divided into empiric treatment group (n = 1025) and individualized treatment group (n = 1038) depending on whether taken CYP2C19 genetic testing. The incidences of clinical endpoint events were compared in two groups at 1-year follow-up. The effective endpoint events were major adverse cardiovascular events (MACEs), including all-cause mortality, in-stent restenosis, nonfatal myocardial infarction, nonfatal stroke and severe recurrent ischemia. Meanwhile, the safe endpoint was bleeding events defined by the Bleeding Academic Research Consortium (BARC) criteria. RESULTS: Finally, 66.83% patients were diagnosed with ACS and 33.17% patients were diagnosed with CCS in empiric group. 68.11% patients were diagnosed with ACS and 31.89% patients were diagnosed with CCS in individualized group. At 1-year follow-up, individualized group showed lower MACEs rate than empiric group (19.61% vs. 10.69%, HR: 1.915; 95% CI: 1.534 to 2.392; P < 0.0001, log-rank test; adjusted HR: 1.983; 95% CI: 1.573 to 2.501; P = 0.000, cox proportional hazards regression models), while bleeding events were significantly less common in empiric group than in individualized group (7.32% vs. 10.40%, HR: 0.693; 95% CI: 0.519 to 0.926; P = 0.0132, log-rank test; adjusted HR: 0.695; 95% CI: 0.518 to 0.933; P = 0.016, cox proportional hazards regression models). It was mainly manifested in BARC class 1 bleeding, which did not warrant the interruption of antiplatelet therapy (ITA). Further, subgroup analyses illustrated that no significant difference existed in cumulative MACEs-free survival rate between all treatment arms of individualized group (P = 0.6579 by log-rank test), and CYP2C19 intermediate metabolizer (IM) genetype appeared to be significantly associated with bleeding events for patients treated with ticagrelor (clopidogrel vs. ticagrelor: 6.80% vs. 14.88%; adjusted HR:0.440; 95% CI: 0.246 to 0.787; adjusted P = 0.006). CONCLUSIONS: Genotype-guided selection of P2Y12 inhibitor made a very positive contribution on the prognosis in Chinese ACS/CCS patients undergoing PCI. Instead of intensifying antiplatelet strategies, conventional-dose clopidogrel could be recommended as P2Y12 inhibitor after weighing MACEs and bleeding events in CYP2C19 IM patients.


Asunto(s)
Síndrome Coronario Agudo , Intervención Coronaria Percutánea , Humanos , Clopidogrel/uso terapéutico , Ticagrelor/uso terapéutico , Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/genética , Síndrome Coronario Agudo/cirugía , Inhibidores de Agregación Plaquetaria , Citocromo P-450 CYP2C19/genética , Intervención Coronaria Percutánea/efectos adversos , Estudios Retrospectivos , Genotipo , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Pronóstico , Resultado del Tratamiento
17.
Org Lett ; 25(28): 5179-5184, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37415264

RESUMEN

Rh (III)-catalyzed dienylation and cyclopropylation of 1,2,3-benzotriazinones with alkylidenecyclopropanes (ACPs) has been achieved. Different from the previous reports of 1,2,3-benzotriazinones, the triazinone ring remained intact in this C-H bond functionlization reaction. Also, the denitrogenative cyclopropylation could also be realized by changing the reaction temperature. This protocol is featured with high E selectivity, wide substrate scope, and divergent structures of products.

18.
Sci Adv ; 9(23): eadh8502, 2023 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-37285440

RESUMEN

As a defense strategy against viruses or competitors, some microbes use anticodon nucleases (ACNases) to deplete essential tRNAs, effectively halting global protein synthesis. However, this mechanism has not been observed in multicellular eukaryotes. Here, we report that human SAMD9 is an ACNase that specifically cleaves phenylalanine tRNA (tRNAPhe), resulting in codon-specific ribosomal pausing and stress signaling. While SAMD9 ACNase activity is normally latent in cells, it can be activated by poxvirus infection or rendered constitutively active by SAMD9 mutations associated with various human disorders, revealing tRNAPhe depletion as an antiviral mechanism and a pathogenic condition in SAMD9 disorders. We identified the N-terminal effector domain of SAMD9 as the ACNase, with substrate specificity primarily determined by a eukaryotic tRNAPhe-specific 2'-O-methylation at the wobble position, making virtually all eukaryotic tRNAPhe susceptible to SAMD9 cleavage. Notably, the structure and substrate specificity of SAMD9 ACNase differ from known microbial ACNases, suggesting convergent evolution of a common immune defense strategy targeting tRNAs.


Asunto(s)
Anticodón , ARN de Transferencia de Fenilalanina , Humanos , Anticodón/genética , ARN de Transferencia de Fenilalanina/genética , ARN de Transferencia de Fenilalanina/metabolismo , Codón , ARN de Transferencia/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética
19.
Front Immunol ; 14: 1162175, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37180138

RESUMEN

Background: Obesity is often accompanied by lower 25(OH)D levels, whereas these two parameters exhibit opposite effects on bone health. It is uncertain what are the effects of lower 25(OH)D levels in obesity on bone health in elderly Chinese people. Methods: A nationally representative cross-sectional analysis of China Community-based Cohort of Osteoporosis (CCCO) was performed from 2016 to 2021, which consisted of 22,081 participants. Demographic data, disease history, Body mass index (BMI), bone mineral density (BMD), the levels of the biomarkers of vitamin D status and those of bone metabolism markers were measured for all participants (N = 22,081). The genes (rs12785878, rs10741657, rs4588, rs7041, rs2282679 and rs6013897) related to 25(OH)D transportation and metabolism were performed in a selected subgroup (N = 6008). Results: Obese subjects exhibited lower 25(OH)D levels (p < 0.05) and higher BMD (p < 0.001) compared with those of normal subjects following adjustment. The genotypes and allele frequency of rs12785878, rs10741657, rs6013897, rs2282679, rs4588 and rs7041 indicated no significant differences among three BMI groups following correction by the Bonferroni's method (p > 0.05). The levels of total 25(OH)D (ToVD) were significantly different among the GC1F, GC1S and GC2 haplotype groups (p < 0.05). Correlation analysis indicated that ToVD levels were significantly correlated with parathyroid hormone levels, BMD, risk of osteoporosis (OP) and the concentration levels of other bone metabolism markers (p < 0.05). Generalized varying coefficient models demonstrated that the increasing BMI, ToVD levels and their interactions were positively associated with BMD outcomes (p < 0.001), whereas the reduced levels of ToVD and BMI increased the risk of OP, which was noted notably for the subjects with reduced ToVD levels (less than 20.69 ng/ml) combined with decreased BMI (less than 24.05 kg/m2). Conclusion: There was a non-linear interaction of BMI and 25(OH)D. And higher BMI accompanied by decreased 25(OH)D levels is associated with increased BMD and decreased incidence of OP, optimal ranges exist for BMI and 25(OH)D levels. The cutoff value of BMI at approximately 24.05 kg/m2 combined with an approximate value of 25(OH)D at 20.69 ng/ml are beneficial for Chinese elderly subjects.


Asunto(s)
Densidad Ósea , Osteoporosis , Humanos , Anciano , Estudios Transversales , Densidad Ósea/genética , Pueblos del Este de Asia , Obesidad/genética , Osteoporosis/epidemiología , Osteoporosis/genética
20.
bioRxiv ; 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37066395

RESUMEN

Robustness is the invariant development of phenotype despite environmental changes and genetic perturbations. In the Arabidopsis flower bud, four sepals initiate at robust positions and times and grow to equal size to enclose and protect the inner floral organs. We previously characterized the mutant development related myb-like1 (drmy1), where 3-5 sepals initiate at irregular positions and variable times and grow to different sizes, compromising their protective function. The molecular mechanism underlying this loss of robustness was unclear. Here, we show that drmy1 has reduced TARGET OF RAPAMYCIN (TOR) activity, ribosomal content, and translation. Translation reduction decreases the protein level of ARABIDOPSIS RESPONSE REGULATOR7 (ARR7), a rapidly synthesized and degraded cytokinin signaling inhibitor. The resultant upregulation of cytokinin signaling disrupts the robust positioning of auxin signaling, causing variable sepal initiation. Our work shows that the homeostasis of translation, a ubiquitous cellular process, is crucial for the robust spatiotemporal patterning of organogenesis.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA