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Nanozyme-based metabolic regulation triggered by tumor-specific endogenous stimuli has emerged as a promising therapeutic strategy for tumors. The current efficacy, however, is constrained by the limited concentration of endogenous substrates and the metabolic plasticity of tumors. Consequently, the implementation of efficient metabolic regulation in tumor therapy is urgently needed. Herein, a versatile nanozyme-based nicotinamide adenine dinucleotide (NADH) circulating oxidation nanoreactor is reported. First, the synthesized cobalt-doped hollow carbon spheres (Co-HCS) possess NADH oxidase (NOX)-mimicking activity for the NADH oxidation to disrupt oxidative phosphorylation (OXPHOS) pathway of tumor cells. Second, the substrate-cycle manner of Co-HCS can be used for NADH circulating oxidation to overcome the limitation of substrate deficiency. Finally, 2-Deoxy-D-glucose (2-DG) and 6-aminonicotinamide (6-AN) are introduced to block glycolysis and pentose phosphate pathway (PPP), thus creating a versatile nanozyme-based NADH circulating oxidation nanoreactor (Co-HCS/D/A) for tumor therapy through triple cellular metabolism disruption. In vitro and in vivo results demonstrate that the designed nanoreactor not only enhances the catalytic efficiency but also disrupts the tumor metabolic homeostasis, leading to efficient therapy outcome. This study develops a novel NADH circulating oxidation nanoreactor for tumor therapy through triple cellular metabolism disruption, which addresses the limitations of current nanozyme-based metabolism regulation for tumor therapy.
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NAD , Oxidación-Reducción , NAD/metabolismo , NAD/química , Humanos , Animales , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Línea Celular Tumoral , RatonesRESUMEN
Hollow silica spheres have been widely studied for drug delivery because of their excellent biosecurity and high porosity. However, difficulties with degradation in the tumor microenvironment (TME) and premature leaking during drug delivery limit their clinical applications. To alleviate these problems, herein, hollow organosilica spheres (HOS) were initially prepared using a "selective etching strategy" and loaded with a photothermal drug: new indocyanine green (IR820). Then, the Cu2+-tannic acid complex (Cu-TA) was deposited on the surface of the HOS, and a new nanoplatform named HOS@IR820@Cu-TA (HICT) was finally obtained. The deposition of Cu-TA can gate the pores of HOS completely to prevent the leakage of IR820 and significantly enhance the loading capacity of HOS. Once in the mildly acidic TME, the HOS and outer Cu-TA decompose quickly in response, resulting in the release of Cu2+ and IR820. The released Cu2+ can react with the endogenous glutathione (GSH) to consume it and produce Cu+, leading to the enhanced production of highly toxic ·OH through a Fenton-like reaction due to the overexpressed H2O2 in the TME. Meanwhile, the ·OH generation was remarkably enhanced by the NIR light-responsive photothermal effect of IR820. These collective properties of HICT enable it to be a smart nanomedicine for dually enhanced chemodynamic therapy through GSH depletions and NIR light-triggered photothermal effects.
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Complejos de Coordinación , Nanopartículas , Neoplasias , Polifenoles , Humanos , Peróxido de Hidrógeno , Sistemas de Liberación de Medicamentos , Glutatión , Microambiente Tumoral , Línea Celular TumoralRESUMEN
BACKGROUND: SQUAMOSA promoter-binding protein-like (SPL) transcription factors are widely present in plants and are involved in signal transduction, the stress response and development. The SPL gene family has been characterized in several model species, such as A. thaliana and G. max. However, there is no in-depth analysis of the SPL gene family in forage, especially alfalfa (Medicago sativa L.), one of the most important forage crops worldwide. RESULT: In total, 76 putative MsSPL genes were identified in the alfalfa genome with an uneven distribution. Based on their identity and gene structure, these MsSPLs were divided into eight phylogenetic groups. Seventy-three MsSPL gene pairs arose from segmental duplication events, and the MsSPLs on the four subgenomes of individual chromosomes displayed high collinearity with the corresponding M. truncatula genome. The prediction of the cis-elements in the promoter regions of the MsSPLs detected two copies of ABA (abscisic acid)-responsive elements (ABREs) on average, implying their potential involvement in alfalfa adaptation to adverse environments. The transcriptome sequencing of MsSPLs in roots and leaves revealed that 54 MsSPLs were expressed in both tissues. Upon salt treatment, three MsSPLs (MsSPL17, MsSPL23 and MsSPL36) were significantly regulated, and the transcription level of MsSPL36 in leaves was repressed to 46.6% of the control level. CONCLUSION: In this study, based on sequence homology, we identified 76 SPL genes in the alfalfa. The SPLs with high identity shared similar gene structures and motifs. In total, 71.1% (54 of 76) of the MsSPLs were expressed in both roots and leaves, and the majority (74.1%) preferred underground tissues to aerial tissues. MsSPL36 in leaves was significantly repressed under salt stress. These findings provide comprehensive information regarding the SPB-box gene family for improve alfalfa tolerance to high salinity.
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Regulación de la Expresión Génica de las Plantas , Medicago sativa , Ácido Abscísico/metabolismo , Medicago sativa/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Estrés Salino/genética , Estrés Fisiológico/genéticaRESUMEN
Nitrate (NO3-) and ammonium (NH4+) are the main nitrogen (N) sources and key determinants for plant growth and development. In recent decades, NH4+, which is a double-sided N compound, has attracted considerable amounts of attention from researchers. Elucidating the mechanisms of NH4+ toxicity and exploring the means to overcome this toxicity are necessary to improve agricultural sustainability. In this review, we discuss the current knowledge concerning the energy consumption and production underlying NH4+ metabolism and toxicity in plants, such as N uptake; assimilation; cellular pH homeostasis; and functions of the plasma membrane (PM), vacuolar H+-ATPase and H+-pyrophosphatase (H+-PPase). We also discuss whether the overconsumption of energy is the primary cause of NH4+ toxicity or constitutes a fundamental strategy for plants to adapt to high-NH4+ stress. In addition, the effects of regulators on energy production and consumption and other physiological processes are listed for evaluating the possibility of high energy costs associated with NH4+ toxicity. This review is helpful for exploring the tolerance mechanisms and for developing NH4+-tolerant varieties as well as agronomic techniques to alleviate the effects of NH4+ stress in the field.
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Compuestos de Amonio , Compuestos de Amonio/metabolismo , Compuestos de Amonio/toxicidad , Nitratos/metabolismo , Nitrógeno/metabolismo , Raíces de Plantas/metabolismo , Plantas/metabolismoRESUMEN
The surface modification of nano particles is very important in nanotechnology. Grafting from (GF) and grafting to (GT) are two main methods to prepare surface modified nanoparticles like nanocellulose crystalline (NCC) grafted with polylactic acid (PLA) chains. In the GF method, the NCC can get high grafting degree but short side chains to improve its compatibility with the polymer matrix. The GT method can help obtain long side chains to increase the chain entanglements but owns low grafting density. To take the advantage of both methods, a mixed modification method combining GT and GF methods was put forward to synthesize comb-like NCC-g-PLA (NP) as a macromolecular modifying agent of PLA. Firstly, GT Method was used to obtain long side-chain NP to improve chain entanglement. Secondly, the GF method was applied to obtain NP-g-PLA (NPL) and NP-g-PDLA (NPD) with additional short side chains to improve its dispersion and compatibility in the PLA matrix. The products showed an enhanced nucleation effect, the degree of crystallinity (Xc) of PLA composites increased almost four times with only 1 wt% NPD or NPL. What's more, the storage modulus and loss modulus of the composite melts also increased with 1 wt% NPL or NPD. The NPD/PLA shows a higher effect than NPL/PLA owning to stronger interaction originated from the stereocomplex (SC) network of PLA matrix with PDLA short chains in NPD.
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BACKGROUND: The grain yield of cereals is determined by the synergistic interaction between source activity and sink capacity. However, source-sink interactions are far from being fully understood. Therefore, a field experiment was performed in wheat to investigate the responses of flag leaves and grains to sink/source manipulations. RESULTS: Half-degraining delayed but partial defoliation enhanced leaf senescence. Sink/source manipulations influenced the content of reactive oxygen species in the flag leaf and the concentration of phytohormones, including cytokinins, indoleacetic 3-acid and jasmonic acid, in the flag leaves (LDef) and grains (GDef) in defoliated plants and flag leaves (LDG) and grain (GDG) in de-grained plants. Isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomic analysis indicated that at 16 days after manipulation, a total of 97 and 59 differentially expressed proteins (DEPs) from various functional categories were observed in the LDG and LDef groups, respectively, compared with the control, and 115 and 121 DEPs were observed in the GDG and GDef groups, respectively. The gene ontology annotation terms of the DEPs mainly included carbon fixation, hydrogen peroxide catabolic process, chloroplast and cytoplasm, oxidoreductase activity and glutamate synthase activity in the flag leaves of manipulated plants and organonitrogen compound metabolic process, cytoplasm, vacuolar membrane, CoA carboxylase activity, starch synthase activity and nutrient reservoir activity in the grains of manipulated plants. KEGG pathway enrichment analysis revealed that photosynthesis, carbon, nitrogen and pyruvate metabolism and glycolysis/gluconeogenesis were the processes most affected by sink/source manipulations. Sink/source manipulations affected the activities of amylase and proteinases and, ultimately, changed the mass per grain. CONCLUSIONS: Manipulations to change the sink/source ratio affect hormone levels; hydrolytic enzyme activities; metabolism of carbon, nitrogen and other main compounds; stress resistance; and leaf senescence and thus influence grain mass.
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Grano Comestible/crecimiento & desarrollo , Hojas de la Planta/crecimiento & desarrollo , Triticum/crecimiento & desarrollo , Envejecimiento/metabolismo , Grano Comestible/metabolismo , Redes y Vías Metabólicas , Microscopía Electrónica de Transmisión , Fotosíntesis , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Proteínas de Plantas/metabolismo , Proteómica , Triticum/metabolismo , Triticum/ultraestructuraRESUMEN
Photosynthesis in non-foliar organs plays an important role in crop growth and productivity, and it has received considerable research attention in recent years. However, compared with the capability of photosynthetic CO2 fixation in leaves, the distinct attributes of photosynthesis in the non-foliar organs of wheat (a C3 species) are unclear. This review presents a comprehensive examination of the photosynthetic characteristics of non-foliar organs in wheat. Compared with leaves, non-foliar organs had a higher capacity to refix respired CO2 , higher tolerance to environmental stresses and slower terminal senescence after anthesis. Additionally, whether C4 photosynthetic metabolism exists in the non-foliar organs of wheat is discussed, as is the advantage of photosynthesis in non-foliar organs during times of abiotic stress. Introducing the photosynthesis-related genes of C4 plants into wheat, which are specifically expressed in non-foliar organs, can be a promising approach for improving wheat productivity.
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Grano Comestible/metabolismo , Fotosíntesis/fisiología , Dióxido de Carbono/metabolismo , Triticum/metabolismoRESUMEN
Drought is an important environmental factor that can severely affect plant growth and reproduction. Although many genes related to drought tolerance have been studied in economically important crops, very few genes have been functionally identified in Malus sieversii. In this study, we isolated a new gene based on throughput RNA sequencing analysis and constructed genetic expression vectors and transformed in Arabidopsis thaliana for functional verification. The results showed that MsUspA ectopic expression driven by constitutive (CaMV 35S) promoter gave rise to substantial improvements in ability of transgenic A. thaliana plants to survive under extreme drought conditions. Improved drought resistance mainly depends on more compact cellular structure, longer roots, strong resilience and low-level ROS. Molecular expression analysis showed that MsUspA may be involved in hormone and secondary metabolite synthesis regulation to improve drought resistance.
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Arabidopsis/fisiología , Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Choque Térmico/genética , Malus/fisiología , Proteínas de Plantas/genética , Estrés Fisiológico/genética , Arabidopsis/genética , Proteínas de Choque Térmico/metabolismo , Malus/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/fisiologíaRESUMEN
Medium-chain fatty acids have attracted significant attention as sources of biofuels in recent years. Acyl-ACP thioesterase, which is considered as the key enzyme to determine the carbon chain length, catalyzes the termination of de novo fatty acid synthesis. Although recombinant medium-chain acyl-ACP thioesterase (TE) affects the fatty acid profile in heterologous cells, tailoring of the fatty acid composition merely by engineering a specific TE is still intractable. In this study, the activity of a C8-C10-specific thioesterase FatB2 from Cuphea hookeriana on C10-ACP was quantified twice as high as that on C8-ACP based on a synthetic C8-C16 acyl-ACP pool in vitro. Whereas in vivo, it was demonstrated that ChFatB2 preferred to accumulate C8 fatty acids with 84.9% composition in the ChFatB2-engineered E. coli strain. To achieve C10 fatty acid production, ChFatB2 was rationally tuned based on structural investigation and enzymatic analysis. An I198E mutant was identified to redistribute the C8-ACP flow, resulting in C10 fatty acid being produced as the principal component at 57.6% of total fatty acids in vivo. It was demonstrated that the activity of TE relative to ß-ketoacyl-ACP synthases (KAS) directly determined the fatty acid composition. Our results provide a prospective strategy in tailoring fatty acid synthesis by tuning of TE activities based on TE-ACP interaction.
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Ácidos Grasos/biosíntesis , Microbiología Industrial/métodos , Tioléster Hidrolasas/metabolismo , Escherichia coli/genética , Organismos Modificados Genéticamente/genética , Organismos Modificados Genéticamente/metabolismo , Tioléster Hidrolasas/genéticaRESUMEN
OBJECTIVE: To investigate the prevalence and subtype distribution of human papillomavirus (HPV) infection and its correlation with age among women in Beijing urban area, and provide some epidemiological evidence for the clinical application of HPV vaccines. METHODS: We collected cervical specimens from 1999 women in the Outpatient Department of our hospital, performed genetyping of HPV-DNA, and analyzed the incidence of HPV infection in different age groups. RESULTS: HPV infection was detected in 502 (25.2%) of the 1999 women patients, with 391 (19.6%) cases of high-risk HPV, which included 326 (83.4%, 326/391) cases of single infection. HPV-16 was the most common type (21.2%, 69/326), followed by HPV-52 (19.3%, 63/326) and HPV-58 (16.0%, 52/326). The prevalence of HPV infection was the highest among the women aged 41 -50 years and the lowest among those over 60 years. CONCLUSION: The subtype- and age-specific distribution of HPV infection among women in Beijing urban area shows an obvious heterogeneity, which deserves due consideration in the clinical application of HPV vaccines.
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Infecciones por Papillomavirus/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , China/epidemiología , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Papillomaviridae/clasificación , Papillomaviridae/genética , Adulto JovenRESUMEN
Ammonium (NH4+) toxicity is ubiquitous in plants. To investigate the underlying mechanisms of this toxicity and bicarbonate (HCO3-)-dependent alleviation, wheat plants were hydroponically cultivated in half-strength Hoagland nutrient solution containing 7.5 mM NO3- (CK), 7.5 mM NH4+ (SA), or 7.5 mM NH4+ + 3 mM HCO3- (AC). Transcriptomic analysis revealed that compared to CK, SA treatment at 48 h significantly upregulated the expression of genes encoding fermentation enzymes (pyruvate decarboxylase (PDC), alcohol dehydrogenase (ADH), and lactate dehydrogenase (LDH)) and oxygen consumption enzymes (respiratory burst oxidase homologs, dioxygenases, and alternative oxidases), downregulated the expression of genes encoding oxygen transporters (PIP-type aquaporins, non-symbiotic hemoglobins), and those involved in energy metabolism, including tricarboxylic acid (TCA) cycle enzymes and ATP synthases, but upregulated the glycolytic enzymes in the roots and downregulated the expression of genes involved in the cell cycle and elongation. The physiological assay showed that SA treatment significantly increased PDC, ADH, and LDH activity by 36.69%, 43.66%, and 61.60%, respectively; root ethanol concentration by 62.95%; and lactate efflux by 23.20%, and significantly decreased the concentrations of pyruvate and most TCA cycle intermediates, the complex V activity, ATP content, and ATP/ADP ratio. As a consequence, SA significantly inhibited root growth. AC treatment reversed the changes caused by SA and alleviated the inhibition of root growth. In conclusion, NH4+ treatment alone may cause hypoxic stress in the roots, inhibit energy generation, suppress cell division and elongation, and ultimately inhibit root growth, and adding HCO3- remarkably alleviates the NH4+-induced inhibitory effects on root growth largely by attenuating the hypoxic stress.
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The metabolite transport inhibition of tumor cells holds promise to achieve anti-tumor efficacy. Herein, we presented an innovative strategy to hinder the delivery of metabolites through the in-situ besieging tumor cells with polyphenolic polymers that strongly adhere to the cytomembrane of tumor cells. Simultaneously, these polymers underwent self-crosslinking under the induction of tumor oxidative stress microenvironment to form an adhesive coating on the surface of the tumor cells. This polyphenol coating effectively obstructed glucose uptake, reducing metabolic products such as lactic acid, glutathione, and adenosine triphosphate, while also causing reactive oxygen species to accumulate in the tumor cells. The investigation of various tumor models, including 2D cells, 3D multicellular tumor spheroids, and xenograft tumors, demonstrated that the polyphenolic polymers effectively inhibited the growth of tumor cells by blocking key metabolite transport processes. Moreover, this highly adhesive coating could bind tumor cells to suppress their metastasis and invasion. This work identified polyphenolic polymers as a promising anticancer candidate with a mechanism by impeding the mass transport of tumor cells.
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Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Polímeros/farmacología , Polifenoles/farmacología , Esferoides Celulares , Glutatión , Microambiente TumoralRESUMEN
The selective elimination of cytotoxic ROS while retaining essential ones is pivotal in the management of chronic inflammation. Co-occurring bacterial infection further complicates the conditions, necessitating precision and an efficacious treatment strategy. Herein, the dynamic ROS nanomodulators are rationally constructed through regulating the surface states of herbal carbon dots (CDs) for on-demand inflammation or infection elimination. The phenolic OH containing CDs derived from honeysuckle (HOCD) and dandelion (DACD) demonstrated appropriate redox potentials, ensuring their ability to scavenge cytotoxic ROS such as ·OH and ONOO-, while invalidity toward essential ones such as O2·-, H2O2, and NO. This enables efficient treatment of chronic inflammation without affecting essential ROS signal pathways. The surface C-N/CâN of CDs derived from taxus leaves (TACD) and DACD renders them with suitable band structures, facilitating absorption in the red region and efficient generation of O2·- upon light irradiation for sterilization. Specifically, the facilely prepared DACD demonstrates fascinating dynamic ROS modulating ability, making it highly suitable for addressing concurrent chronic inflammation and infection, such as diabetic wound infection. This dynamic ROS regulation strategy facilitates the realization of the precise and efficient treatment of chronic inflammation and infection with minimal side effects, holding immense potential for clinical practice.
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Carbono , Inflamación , Puntos Cuánticos , Especies Reactivas de Oxígeno , Carbono/química , Carbono/farmacología , Especies Reactivas de Oxígeno/metabolismo , Inflamación/tratamiento farmacológico , Animales , Ratones , Puntos Cuánticos/química , Humanos , Células RAW 264.7 , Propiedades de SuperficieRESUMEN
OBJECTIVE: To investigate the factors influencing the degree of disability in patients with neuromyelitis optica spectrum disorder (NMOSD) and provide evidence for disease monitoring and clinical intervention. METHODS: Eighty-four patients with NMOSD at Xuanwu Hospital Capital Medical University were enrolled in this retrospective study. Before treatment, blood was collected from all patients, and their expanded disability status scores were assessed. RESULTS: Of the 84 patients assessed, 66 (78.57%) had an expanded disability status scale score < 7, and 18 (21.43%) had scores ≥ 7. The univariate analysis showed that the total bilirubin (TBil), cerebrospinal fluid albumin (CSF ALB), cerebrospinal fluid immunoglobulin G (CSF IgG), QALB, and QIgG levels in the group with scores ≥ 7 were significantly different from those with scores < 7 (P < 0.05). In addition, Spearman's correlation analysis showed a significant correlation between ALB and expanded disability status scores in patients with NMOSD (P < 0.05), and the multivariate logistic regression analysis showed that TBil was an independent factor influencing the degree of disability in patients with NMOSD (P < 0.05). The receiver operating characteristic curve was constructed using TBil values; the area under the curve of TBil was 0.729 (P < 0.01), and the best cut-off value was 11.015 g/L. Its sensitivity in predicting the severity of disability in NMOSD patients was 51.5% while its specificity was 88.9%. CONCLUSION: TBil is an independent factor that influences the severity of disability in patients with NMOSD. In addition, ALB is closely related to NMOSD severity, and some factors associated with the BBB are significantly increased in severely disabled NMOSD patients.
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Neuromielitis Óptica , Humanos , Neuromielitis Óptica/líquido cefalorraquídeo , Neuromielitis Óptica/complicaciones , Estudios Retrospectivos , Barrera HematoencefálicaRESUMEN
Carbon dots (CDs) have emerged as promising nanomaterials for bioimaging-guided photodynamic therapy (PDT). However, designing red-emissive CDs (RCDs) with tunable type I and type II reactive oxygen species (ROS) generation to simultaneously meet PDT applications in aerobic and hypoxic scenarios still remain major challenges. Herein, three types of RCDs with maximum emission at approximately 680 nm are successfully prepared. It is noteworthy that they exhibit the adjustable ROS production with equal superoxide anion (via type I PDT) and incremental singlet oxygen (via type II PDT). Detailed structural and optical characterizations along with theoretical calculation reveal that the unique type I/II ROS formation mainly depends on the core sizes and surface states of RCDs, which determine their identical redox potentials and tapering energy gaps between singlet- and triplet states, respectively. Additionally, due to the inherent mitochondria targeting capability, RCDs enable themselves to induce cell programmed death via activating mitochondrion-mediated apoptotic pathways. This work exploits the unprecedented RCDs with tunable type I and type II ROS generation that could ensure highly efficient tumor eradication both in vitro and in vivo, even under the harsh tumor microenvironment, providing a new prospect for CDs as nanophotosensitizers to conquer the limitations of single type PDT.
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Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Especies Reactivas de Oxígeno/metabolismo , Carbono/química , Neoplasias/tratamiento farmacológico , Mitocondrias/metabolismo , Fármacos Fotosensibilizantes/química , Línea Celular Tumoral , Microambiente TumoralRESUMEN
As an emerging treatment method, photodynamic therapy (PDT) has attracted considerable interest due to the characteristics of non-invasiveness, repeatable treatment, high spatiotemporal resolution and few side effects. However, the life span (<40 ns) and diffusion distance (<20 nm) of reactive oxygen species such as singlet oxygen (1O2) in tumor cells are extremely short, which has seriously limited therapeutic efficacy of PDT. The enrichment site of photosensitizers in cancer cells is usually the first site of PDT action, which will not only affect the biological signaling pathway of cancer cell death, but also is closely related to the final therapeutic effect. Therefore, the design and preparation of photosensitizers targeting specific subcellular organelles can directly break the biological function of the organelle and trigger the corresponding cell death signaling pathway, which can significantly improve the efficacy of PDT. Herein, a lysosome-targeted silicon quantum dots (L-Si QDs) was first made by diethylene glycol-mediated synthetic route as a multicolor fluorescent imaging reagents and a new photosensitizer. The as-prepared L-Si QDs exhibit bright fluorescence with excellent pH stability and time stability, excitation-dependent emission, and good biocompatibility. Furthermore, the results of cell experiments showed that L-Si QDs was accumulated in lysosomes after being taken up by cancer cells, and can efficiently produce1O2upon 635 nm laser irradiation, which can damage lysosomes, up-regulate cleavage caspase-3, increase Bax release, down-regulate Bcl-2 and induce cell apoptosis finally. This study significantly broadens the biomedical applications of silicon quantum dots and provides excellent nanomaterials candidates for tumor phototherapy.
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Neoplasias , Fotoquimioterapia , Puntos Cuánticos , Humanos , Fármacos Fotosensibilizantes , Fotoquimioterapia/métodos , Silicio , Medicina de Precisión , Neoplasias/tratamiento farmacológico , LisosomasRESUMEN
Pyroptosis is increasingly considered a new weathervane in cancer immune therapy. However, triggering specific pyroptotic tumor cell death while preserving normal cells still remains a major challenge. Herein, a brand-new pyroptosis inducer, copper-bacteriochlorin nanosheet (Cu-TBB), is designed. The synthesized Cu-TBB can be activated to an "on" state in the tumor microenvironment with glutathione (GSH) overexpression, leading to the release of Cu+ and TBB, respectively. Intriguingly, the released Cu+ can drive cascade reactions to produce O2 -⢠and highly toxic ·OH in cells. Additionally, the released TBB can also generate O2 -⢠and 1 O2 upon 750 nm laser irradiation. Encouragingly, both Cu+ -driven cascade reactions and photodynamic therapy pathways result in potent pyroptosis along with dendritic cell maturation and T cell priming, thus simultaneously eliminating the primary tumors and inhibiting the distant tumor growth and metastases. Conclusively, the well-designed Cu-TBB nanosheet is shown to trigger specific pyroptosis in vitro and in vivo, leading to enhanced tumor immunogenicity and antitumor efficacy while minimizing systemic side effects.
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Neoplasias , Porfirinas , Humanos , Piroptosis , Cobre , Inmunoterapia , Glutatión , Microambiente Tumoral , Línea Celular Tumoral , Neoplasias/terapiaRESUMEN
Wheat is one of the most important food crops worldwide. In recent decades, fertilizers, especially nitrogen (N), have been increasingly utilized to maximize wheat productivity. However, a large proportion of N is not used by plants and is in fact lost into the environment and causes serious environmental pollution. Therefore, achieving a low N optimum via efficient physiological and biochemical processes in wheat grown under low-N conditions is highly important for agricultural sustainability. Although N stress-related N capture in wheat has become a heavily researched subject, how this plant adapts and responds to N starvation has not been fully elucidated. This review summarizes the current knowledge on the signaling mechanisms activated in wheat plants in response to N starvation. Furthermore, we filled the putative gaps on this subject with findings obtained in other plants, primarily rice, maize, and Arabidopsis. Phytohormones have been determined to play essential roles in sensing environmental N starvation and transducing this signal into an adjustment of N transporters and phenotypic adaptation. The critical roles played by protein kinases and critical kinases and phosphatases, such as MAPK and PP2C, as well as the multifaceted functions of transcription factors, such as NF-Y, MYB, DOF, and WRKY, in regulating the expression levels of their target genes (proteins) for low-N tolerance are also discussed. Optimization of root system architecture (RSA) via root branching and thinning, improvement of N acquisition and assimilation, and fine-tuned autophagy are pivotal strategies by which plants respond to N starvation. In light of these findings, we attempted to construct regulatory networks for RSA modification and N uptake, transport, assimilation, and remobilization.
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Ammonium (NH4+) is one of the most important nutrients required by plants. However, a high concentration of NH4+ as the sole nitrogen source suppresses plant growth. Although nitrate (NO3-) can alleviate NH4+ toxicity, the mechanisms underlying this ability have not been fully elucidated. In this study, wheat plants were cultivated in hydroponic solution with 7.5 mM NO3- (control), 7.5 mM NH4+ (sole ammonium, SA) or 7.5 mM NH4+ plus 1.0 mM NO3- (ammonium and nitrate, AN). The results showed that compared with the control, the SA treatment significantly decreased root growth, protein content and the concentrations of most intermediates and the activity of enzymes from the tricarboxylic acid (TCA) cycle. Moreover, increased the activity of plasma membrane H+-ATPase and the rate of H+ efflux along roots, caused solution acidification, and increased the activity of mitochondrial respiratory chain complexes I-IV and the contents of protein-bound carbonyls and malondialdehyde in roots. SA treatment induced ultrastructure disruption and reduced the viability of root cells. Compared with the SA treatment, the AN treatment increased root growth, protein content, the concentrations of most intermediates and the activity of enzymes from the TCA cycle. Furthermore, AN treatment decreased the rate of H+ efflux, retarded medium acidification, decreased protein carbonylation and lipid peroxidation in roots and relieved ultrastructure disruption and increased the viability of root cells. Taken together, these results indicate that NO3--dependent alleviation of NH4+ toxicity in wheat seedlings is closely associated with physiological processes that mediate TCA cycle, relieve rhizospheric acidification and decrease the production of ROS and oxidative damage.
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Compuestos de Amonio , Compuestos de Amonio/metabolismo , Ciclo del Ácido Cítrico , Concentración de Iones de Hidrógeno , Nitratos/metabolismo , Nitrógeno/metabolismo , Estrés Oxidativo , Raíces de Plantas/metabolismo , Triticum/metabolismoRESUMEN
Salt stress is the main abiotic factor affecting alfalfa yield and quality. However, knowledge of the genetic basis of the salt stress response in alfalfa is still limited. Here, a genome-wide association study (GWAS) involving 875,023 single-nucleotide polymorphisms (SNPs) was conducted on 220 alfalfa varieties under both normal and salt-stress conditions. Phenotypic analysis showed that breeding status and geographical origin play important roles in the alfalfa salt stress response. For germination ability under salt stress, a total of 15 significant SNPs explaining 9%-14% of the phenotypic variation were identified. For tolerance to salt stress in the seedling stage, a total of 18 significant SNPs explaining 12%-23% of the phenotypic variation were identified. Transcriptome analysis revealed 2,097 and 812 differentially expressed genes (DEGs) that were upregulated and 2,445 and 928 DEGs that were downregulated in the leaves and roots, respectively, under salt stress. Among these DEGs, many encoding transcription factors (TFs) were found, including MYB-, CBF-, NAC-, and bZIP-encoding genes. Combining the results of our GWAS analysis and transcriptome analysis, we identified a total of eight candidate genes (five candidate genes for tolerance to salt stress and three candidate genes for germination ability under salt stress). Two SNPs located within the upstream region of MsAUX28, which encodes an auxin response protein, were significantly associated with tolerance to salt stress. The two significant SNPs within the upstream region of MsAUX28 existed as three different haplotypes in this panel. Hap 1 (G/G, A/A) was under selection in the alfalfa domestication and improvement process.