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Radiotherapy (RT), essential for treating various cancers, faces challenges from tumor hypoxia, which induces radioresistance. A tumor-targeted "prosthetic-Arginine" coassembled nanozyme system, engineered to catalytically generate nitric oxide (NO) and oxygen (O2) in the tumor microenvironment (TME), overcoming hypoxia and enhancing radiosensitivity is presented. This system integrates the prosthetic heme of nitric oxide synthase (NOS) and catalase (CAT) with NO-donating Fmoc-protected Arginine and Ru3+ ions, creating HRRu nanozymes that merge NOS and CAT functionalities. Surface modification with human heavy chain ferritin (HFn) improves the targeting ability of nanozymes (HRRu-HFn) to tumor tissues. In the TME, strategic arginine incorporation within the nanozyme allows autonomous O2 and NO release, triggered by endogenous hydrogen peroxide, elevating NO and O2 levels to normalize vasculature and improve blood perfusion, thus mitigating hypoxia. Employing the intrinsic O2-transporting ability of heme, HRRu-HFn nanozymes also deliver O2 directly to the tumor site. Utilizing esophageal squamous cell carcinoma as a tumor model, the studies reveal that the synergistic functions of NO and O2 production, alongside targeted delivery, enable the HRRu-HFn nanozymes to combat tumor hypoxia and potentiate radiotherapy. This HRRu-HFn nanozyme based approach holds the potential to reduce the radiation dose required and minimize side effects associated with conventional radiotherapy.
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Natural antimicrobial peptides (AMPs) and enzymes (AMEs) are promising non-antibiotic candidates against antimicrobial resistance but suffer from low efficiency and poor stability. Here, we develop peptide nanozymes which mimic the mode of action of AMPs and AMEs through de novo design and peptide assembly. Through modelling a minimal building block of IHIHICI is proposed by combining critical amino acids in AMPs and AMEs and hydrophobic isoleucine to conduct assembly. Experimental validations reveal that IHIHICI assemble into helical ß-sheet nanotubes with acetate modulation and perform phospholipase C-like and peroxidase-like activities with Ni coordination, demonstrating high thermostability and resistance to enzymatic degradation. The assembled nanotubes demonstrate cascade antifungal actions including outer mannan docking, wall disruption, lipid peroxidation and subsequent ferroptotic death, synergistically killing >90% Candida albicans within 10 min on disinfection pad. These findings demonstrate an effective de novo design strategy for developing materials with multi-antimicrobial mode of actions.
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Antifúngicos , Candida albicans , Antifúngicos/farmacologia , Antifúngicos/química , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanotubos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Peroxidação de Lipídeos/efeitos dos fármacos , Peptídeos/farmacologia , Peptídeos/químicaRESUMO
We summarize the copy number variations (CNVs) and phenotype spectrum of infantile epileptic spasms syndrome (IESS) in a Chinese cohort. The CNVs were identified by genomic copy number variation sequencing. The CNVs and clinical data were analyzed. 74 IESS children with CNVs were enrolled. 35 kinds of CNVs were identified. There were 11 deletions and 5 duplications not reported previously in IESS, including 2 CNVs not reported in epilepsy. 87.8% were de novo, 9.5% were inherited from mother and 2.7% from father. Mosaicism occurred in one patient with Xq21.31q25 duplication. 16.2% (12/74) were 1p36 deletion, and 20.3% (15/74) were 15q11-q13 duplication. The age of seizure onset ranged from 17 days to 24 months. Seizure types included epileptic spasms, focal seizures, tonic seizures, and myoclonic seizures. All patients displayed developmental delay. Additional features included craniofacial anomaly, microcephaly, congenital heart defects, and hemangioma. 29.7% of patients were seizure-free for more than 12 months, and 70.3% still had seizures after trying 2 or more anti-seizure medications. In conclusion, CNVs is a prominent etiology of IESS. 1p36 deletion and 15q duplication occurred most frequently. CNV detection should be performed in patients with IESS of unknown causes, especially in children with craniofacial anomalies and microcephaly.
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Variações do Número de Cópias de DNA , Fenótipo , Espasmos Infantis , Humanos , Variações do Número de Cópias de DNA/genética , Espasmos Infantis/genética , Feminino , Masculino , Lactente , Duplicação Cromossômica/genética , Cromossomos Humanos Par 15/genética , Pré-Escolar , Recém-Nascido , Deleção Cromossômica , Mosaicismo , Aberrações Cromossômicas , Deficiência IntelectualRESUMO
Amyloid-like assembly is not only associated with pathological events, but also leads to the development of novel nanomaterials with unique properties. Herein, using Fmoc diphenylalanine peptide (Fmoc-F-F) as a minimalistic model, we found that histidine can modulate the assembly behavior of Fmoc-F-F and induce enzyme-like catalysis. Specifically, the presence of histidine rearranges the ß structure of Fmoc-F-F to assemble nanofilaments, resulting in the formation of active site to mimic peroxidase-like activity that catalyzes ROS generation. A similar catalytic property is also observed in Aß assembled filaments, which is correlated with the spatial proximity between intermolecular histidine and F-F. Notably, the assembled Aß filaments are able to induce cellular ROS elevation and damage neuron cells, providing an insight into the pathological relationship between Aß aggregation and Alzheimer's disease. These findings highlight the potential of histidine as a modulator in amyloid-like assembly of peptide nanomaterials exerting enzyme-like catalysis.
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Histidina , Nanoestruturas , Espécies Reativas de Oxigênio , Proteínas Amiloidogênicas , PeptídeosRESUMO
High invasiveness of glioma produces residual glioma cells in the brain parenchyma after surgery and ultimately causes recurrence. Precise delineation of glioma infiltrative region is critical for an accurate complete resection, which is challenging. The glioma-infiltrating area constitutes infiltration-excluded immune microenvironments (I-E TIMEs), which recruits endogenous or adoptive macrophages to the invasive edge of glioma. Thus, combined with immune cell tracing technology, we provided a novel strategy for the preoperative precise definition of the glioma infiltration boundary, even satellite-like infiltration stoves. Herein, the biomimetic probe was constructed by internalizing fluorophore labeled PEGylated KMnF3 nanoparticles into bone-marrow-derived macrophages using magnetic resonance imaging (MRI)/fluorescence imaging (FI). The biomimetic probe was able to cross the blood-brain barrier and home to the orthotopic glioma infiltrates including satellite stove under MRI and FI tracing, which was validated using hematoxylin and eosin staining, indicating its excellent performance in distinguishing the margins between the glioma cell and normal tissues. This study guides the precise definition of glioma infiltration boundaries at the cellular level, including the observation of any residual glioma cells after surgery. Thus, it has the potential to guide surgery to maximize resection and predict recurrence in the clinic.
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Black carbon (BC) is a product of incomplete or inefficient combustion and may be associated with a variety of adverse effects on human health. The objective of this study was to analyze the association between various mortalities and long-/short-term exposure to BC as an independent pollutant. In this systematic review, we searched 4 databases for original research in English up to 6th October 2022, that investigated population-wide mortality due to BC exposure. We pooled mortality estimates and expressed them as relative risk (RR) per 10 µg/m3 increase in BC. We used a random-effect model to derive the pooled RRs. Of the 3186 studies identified, 29 articles met the eligibility criteria, including 18 long-term exposure studies and 11 short-term exposure studies. In the major meta-analysis and sensitivity analysis, positive associations were found between BC and total mortality and cause-specific disease mortalities. Among them, the short-term effects of BC on total mortality, cardiovascular disease mortality, respiratory disease mortality, and the long-term effects of BC on total mortality, ischemic heart disease mortality, respiratory disease mortality and lung cancer mortality were found to be statistically significant. The heterogeneity of the meta-analysis results was much lower for short-term studies than for long-term. Few studies were at a high risk of bias in any domain. The certainty of the evidence for most of the exposure-outcome pairs was moderate. Our study showed a significantly positive association between short-/long-term BC exposure and various mortalities. We speculate that BC has a higher adverse health effect on the respiratory system than on the cardiovascular system. This is different from the effect of PM2.5. Therefore, more studies are needed to consider BC as a separate pollutant, and not just as a component of PM2.5.
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Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Humanos , Causas de Morte , Poluentes Atmosféricos/análise , Fuligem , Carbono , Exposição Ambiental/análise , Material Particulado/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análiseRESUMO
Being a highly conserved catabolic process, autophagy is induced by various forms of cellular stress, and its modulation has considerable potential as a cancer therapeutic approach. In the present study, it was demonstrated that dicitrinone B (DB), a rare carbonbridged citrinin dimer, may exert anticancer effects by blocking autophagy at a late stage, without disrupting lysosomal function in MCF7 breast cancer and MDAMB231 triplenegative breast cancer cells. Furthermore, it was discovered that DB significantly enhanced intracellular reactive oxygen species (ROS) production and that the removal of ROS was followed by the attenuation of autophagy inhibition. In addition, DB exerted notable inhibitory effects on the proliferation and promoting effects on the apoptosis of MCF7 and MDAMB231 cells. In combination with conventional chemotherapeutic drugs, DB exhibited a further enhanced synergistic effect than when used as a single agent. Overall, the data of the present study demonstrate that DB may prove to be a promising autophagy inhibitor with anticancer activity against breast cancer.
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Produtos Biológicos , Neoplasias da Mama , Citrinina , Neoplasias de Mama Triplo Negativas , Apoptose , Autofagia , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Citrinina/análogos & derivados , Citrinina/farmacologia , Feminino , Humanos , Espécies Reativas de Oxigênio/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológicoRESUMO
Objective: This study aimed to obtain a comprehensive understanding of the genetic and phenotypic aspects of GABRG2-related epilepsy and its prognosis and to explore the potential prospects for personalized medicine. Methods: Through a multicenter collaboration in China, we analyzed the genotype-phenotype correlation and antiseizure medication (ASM) of patients with GABRG2-related epilepsy. The three-dimensional protein structure of the GABRG2 variant was modeled to predict the effect of GABRG2 missense variants using PyMOL 2.3 software. Results: In 35 patients with GABRG2 variants, 22 variants were de novo, and 18 variants were novel. The seizure onset age was ranged from 2 days after birth to 34 months (median age: 9 months). The seizure onset age was less than 1 year old in 22 patients (22/35, 62.9%). Seizure types included focal seizures (68.6%), generalized tonic-clonic seizures (60%), myoclonic seizures (14.3%), and absence seizures (11.4%). Other clinical features included fever-sensitive seizures (91.4%), cluster seizures (57.1%), and developmental delay (45.7%). Neuroimaging was abnormal in 2 patients, including dysplasia of the frontotemporal cortex and delayed myelination of white matter. Twelve patients were diagnosed with febrile seizures plus, eleven with epilepsy and developmental delay, two with Dravet syndrome, two with developmental and epileptic encephalopathy, two with focal epilepsy, two with febrile seizures, and four with unclassified epilepsy. The proportions of patients with missense variants in the extracellular region and the transmembrane region exhibiting developmental delay were 40% and 63.2%, respectively. The last follow-up age ranged from 11 months to 17 years. Seizures were controlled in 71.4% of patients, and 92% of their seizures were controlled by valproate and/or levetiracetam. Conclusion: The clinical features of GABRG2-related epilepsy included seizure onset, usually in infancy, and seizures were fever-sensitive. More than half of the patients had cluster seizures. Phenotypes of GABRG2-related epilepsy were ranged from mild febrile seizures to severe epileptic encephalopathies. Most patients with GABRG2 variants who experienced seizures had a good prognosis. Valproate and levetiracetam were effective treatments for most patients.
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Background: In our clinical work, we found that cancer patients were susceptible to coronary atherosclerotic heart disease (CAD). However, less is known about the relationship between CAD and cancer. The present study aimed to identify the risk factors for CAD and cancer, as well as the relationship between CAD and cancer. Methods: In this retrospective study, 1600 patients between January 2012 and June 2019 were enrolled and divided into groups according to whether they had CAD or cancer. Single-factor and multivariate analysis methods were applied to examine the risk factors for CAD and cancer. Results: (1) Cancer prevalence was significantly higher in patients with CAD than in patients without CAD (47.2 vs. 20.9%). The prevalence of CAD in cancer and non-cancer patients was 78.9 and 52.4%, respectively. (2) Multivariable logistic regression showed that patients with cancer had a higher risk of developing CAD than non-cancer patients (OR: 2.024, 95% CI: 1.475 to 2.778, p < 0.001). Respiratory (OR: 1.981, 95% CI: 1.236-3.175, p = 0.005), digestive (OR: 1.899, 95% CI: 1.177-3.064, p = 0.009) and urogenital (OR: 3.595, 95% CI: 1.696-7.620, p = 0.001) cancers were significantly associated with a higher risk of CAD compared with no cancer. (3) Patients with CAD also had a higher risk of developing cancer than non-CAD patients (OR = 2.157, 95% CI: 1.603 to 2.902, p < 0.001). Patients in the Alanine aminotransferase (ALT) level ≥ 40 U/L group had a lower risk of cancer than patients in the ALT level < 20 U/L group (OR: 0.490, 95% CI: 0.333-0.722, p < 0.001). (4) An integrated variable (Y = 0.205 × 10-1 age - 0.595 × 10-2 HGB - 0.116 × 10-1 ALT + 0.135 FIB) was identified for monitoring the occurrence of cancer among CAD patients, with an AUC of 0.720 and clinical sensitivity/specificity of 0.617/0.711. Conclusion: (1) We discovered that CAD was an independent risk factor for cancer and vice versa. (2) Digestive, respiratory and urogenital cancers were independent risk factors for CAD. (3) We created a formula for the prediction of cancer among CAD patients. (4) ALT, usually considered a risk factor, was proven to be a protective factor for cancer in this study.
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Edible oils, especially peanut oil, usually contain aflatoxin B1 (AFB1) at extremely high concentrations. This study focused on the synthesis of rice husk-based mesoporous silica (MCM-41) for the removal of AFB1 from peanut oil. MCM-41 was characterized by X-ray diffraction, N2 physisorption, and transmission electron microscope. MCM-41 was shown to have ordered channels with high specific surface area (1246 m2/g), pore volume (1.75 cm3/g), and pore diameter (3.11 nm). Under the optimal concentration of 1.0 mg/mL of the adsorbent dose, the adsorption behavior of MCM-41, natural montmorillonite (MONT), and commercial activated carbon (CA) for AFB1 were compared. The adsorption of AFB1 in peanut oil onto the three adsorbents was slower compared to that of AFB1 in an aqueous solution. In addition, the pseudo-second-order kinetic model better fit the adsorption kinetics of AFB1, while the adsorption mechanism followed the Langmuir adsorption isotherm on the three adsorbents. The calculated maximum adsorbed amounts of AFB1 on MONT, MCM-41, and CA were 199.41, 215.93, and 248.93 ng/mg, respectively. These results suggested that MCM-41 without modification could meet market demand and could be considered a good candidate for the removal of AFB1 from peanut oil. This study provides insights that could prove to be of economic and practical value.
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Aflatoxina B1/química , Oryza , Óleo de Amendoim/química , Dióxido de Silício/química , Adsorção , Contaminação de Alimentos/prevenção & controleRESUMO
OBJECTIVE: This study aimed to comprehensively examine the genetic and phenotypic aspects of GABRB3-related epilepsy and to explore the potential prospects of personalized medicine. METHODS: Genetic testing was conducted in all epilepsy patients without acquired factors for epilepsy. Through the collaboration of multicenter in China, we analyzed the genotype-phenotype correlation and antiepileptic therapy of 26 patients with GABRB3-related epilepsy. RESULTS: Thirteen GABRB3 variants were novel, and 25 were de novo. The seizure onset age ranged from 1 to 21 months (median age 3.75 months). Seizure types predominated including focal seizures (92.3%), generalized tonic-clonic seizures (23.1%), and epileptic spasms (15.4%). Clinical features included cluster seizures (80.8%), fever sensitivity (53.8%), and developmental delay (96.2%). Neuroimaging was abnormal in 10 patients, including dysplasia of the cerebral cortex, dysplasia of the frontal and temporal cortex, delayed myelination, and corpus callosum dysplasia. Eleven patients were diagnosed with developmental and epileptic encephalopathy (DEE), four with West syndrome, three with epilepsy of infancy with migrating focal seizures (EIMFS), one with epilepsy with myoclonic-atonic seizures (EMAS), one with Dravet syndrome, and one with febrile seizures plus (FS+). Seizures were controlled in 57.7% of patients by valproate, levetiracetam, or perampanel in the majority. CONCLUSIONS: The clinical features of GABRB3-related epilepsy included seizure onset in early infancy, cluster seizures and fever sensitivity. Most patients manifest severe epilepsy phenotypes. Valproate, levetiracetam and perampanel seem to have positive effects on seizure control for patients with GABRB3 variants.
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Epilepsias Mioclônicas , Epilepsia , Convulsões Febris , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Febre , Humanos , Lactente , Levetiracetam , Receptores de GABA-A/genética , Ácido ValproicoRESUMO
Poly γ-glutamic acid (γ-PGA) is attractive due to its desirable biological properties such as nontoxicity, excellent biocompatibility, and minimal immunogenicity. Additionally, γ-PGA could be recognized by γ-glutamyl transpeptidase, which is regarded as a potential biomarker for many tumors. In this study, we have developed a new biodegradable, reduction sensitive, and tumor-specific gene nano-delivery platform consisting of a cationic carrier (SSBPEI) for siRNA condensation, mPEG shell for nanoparticle stabilization, and γ-PGA for accelerated cellular uptake. Disulfide bonds (-SS-) could be reduced specifically in the tumor environment, which is full of reductants such as glutathione reductase. Conjugating polyethylene glycol (PEG) to the γ-PGA led to the formation of mPEG-g-γ-PGA, with a decreased positive charge on the surface of SSBPEI@siRNA and substantially higher stability in an aqueous medium. As a result, mPEG-g-γ-PGA/SSBPEI@siRNA nanoparticles could protect siRNAs from RNase A degradation and release siRNAs in a reduction sensitive way. The multifunctional delivery system was shown to silence the Survivin gene and further promote chemotherapeutic drug-induced apoptosis in the A549 NSCLC cell line efficiently, thereby representing a novel promising platform for the delivery of siRNAs.
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Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Polietilenoglicóis/química , Ácido Poliglutâmico/análogos & derivados , RNA Interferente Pequeno/farmacologia , Células A549 , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Pulmonares/patologia , Estrutura Molecular , Oxirredução , Tamanho da Partícula , Ácido Poliglutâmico/química , RNA Interferente Pequeno/química , Propriedades de Superfície , Células Tumorais CultivadasRESUMO
The existence of cancer stem cells (CSCs) is considered to be the main reason for chemoresistance, metastasis and the ultimate failure of treatment in hepatocellular carcinoma (HCC). However, there are a few chemical agents that may inhibit CSCs. The present study identified that 4,4'bond secalonic acid D (4,4'SAD), a compound isolated from the marinederived fungus Penicillium oxalicum, inhibited the growth of side population (SP) cells isolated from human liver cancer cell lines PLC/PRF/5 and HuH7 by attenuating the expression of ATPbinding cassette superfamily G member 2. Furthermore, the results of wound healing, Transwell, western blotting and reverse transcriptionquantitative PCR assays demonstrated that 4,4'SAD suppressed the invasion and migration of SP cells by downregulating matrix metallopeptidase 9 (MMP9) and upregulating the antagonist tissue inhibitor of metalloproteinases 1 in vitro. Moreover, in vivo study results found that 4,4'SAD had antilung metastasis efficacy via the decrease of MMP9 expression in the H22 HCC model of Kunming mice. Therefore, the present study identified the potential of 4,4'SAD as a promising candidate for the treatment of advanced liver cancer.
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Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Células da Side Population/efeitos dos fármacos , Xantonas/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Penicillium/química , Penicillium/metabolismo , Células da Side Population/citologia , Células da Side Population/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Transplante Heterólogo , Xantonas/química , Xantonas/uso terapêuticoRESUMO
With similar chemistry, Mn and Fe interact in their many essential roles in plants but the magnitude and mechanisms involved of these interactions are poorly understood. Leaves of soybean (a Mn-sensitive species) developed a mild chlorosis and small dark spots and distorted trifoliate leaves with 30 µM Mn and 0.6 µM Fe in nutrient solution (pH 5.6; 3 mM ionic strength). At 0.6 µM Fe, lower alternate leaves of sunflower (a Mn-tolerant species) were chlorotic at 30 µM Mn and had a pale chlorosis and necrosis at 400 µM Mn. A concentration of 30 and 300 µM Fe in solution alleviated these typical symptoms of Mn toxicity and decreased the concentration of Mn from >3000 to ca. 800 mg kg-1 dry mass (DM) in all leaf tissues. As expected, increased Fe supply increased Fe in leaves from <100 up to 1350 mg Fe kg-1 DM. In situ synchrotron-based X-ray fluorescence microscopy showed that increased Fe supply caused an overall decrease in Mn in the leaf tissue but had little effect on the pattern of its distribution. Similarly, X-ray absorption spectroscopy identified only slight effects of Fe supply on Mn speciation in leaf tissues. Thus, the results of this study indicate that increased Fe supply ameliorated Mn toxicity in soybean and sunflower largely through decreased Mn uptake and translocation to leaf tissues rather than through changes in Mn distribution or speciation within the leaves.
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Glycine max/efeitos dos fármacos , Helianthus/efeitos dos fármacos , Ferro/farmacologia , Manganês/farmacologia , Microscopia de Fluorescência/métodos , Espectroscopia por Absorção de Raios X/métodos , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Helianthus/metabolismo , Manganês/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Glycine max/metabolismo , Síncrotrons , Raios XRESUMO
Background and Aims: Salinity affects the bioavailability of cadmium (Cd) in soils and Cd accumulation in plants, but the associated mechanisms remain unclear. This study aimed to assess the metabolic response to NaCl and Cd and the relationship between metabolites and Cd accumulation in the halophyte Carpobrotus rossii, which has potential for Cd phytoextraction. Methods: Plants were grown in nutrient solution with 0-400 mm NaCl in the presence of 5 or 15 µm Cd, with varied or constant solution Cd2+ activity. Plant growth and Cd uptake were measured, and the accumulation of peptides, and organic and amino acids in plant tissues were assessed. Key Results: The addition of NaCl to Cd-containing solutions improved plant growth along with 70-87 % less shoot Cd accumulation, resulting from decreases in Cd root uptake and root-to-shoot translocation irrespective of Cd2+ activity in solutions. Moreover, Cd exposure increased the concentration of phytochelatins, which correlated positively with Cd concentrations in plants regardless of NaCl addition. In comparison, Cd inhibited the synthesis of organic acids in shoots and roots in the absence of NaCl, but increased it in shoots in the presence of NaCl. While Cd increased the concentrations of amino acids in plant shoots, the effect of NaCl on the synthesis of amino acids was inconsistent. Conclusions: Our data provide the first evidence that NaCl decreased Cd shoot accumulation in C. rossii by decreasing Cd root uptake and root-to-shoot translocation even under constant Cd2+ activity. The present study also supports the important role of peptides and organic acids, particular of phytochelatins, in Cd tolerance and accumulation although the changes of those metabolites was not the main reason for the decreased Cd accumulation.
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Aizoaceae/efeitos dos fármacos , Cádmio/metabolismo , Cloreto de Sódio/farmacologia , Aizoaceae/fisiologia , Biodegradação Ambiental , Transporte Biológico , Cádmio/toxicidade , Ácidos Carboxílicos/metabolismo , Glutationa/metabolismo , Fitoquelatinas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/fisiologia , Salinidade , Plantas Tolerantes a Sal , Solo/químicaRESUMO
The occurrence of multidrug resistance (MDR) is highly associated with the overexpression of ATP-binding cassette (ABC) transporters, among which, P-glycoprotein (P-gp) plays one of the most important roles. Iso-pencillixanthone A (iso-PXA) is a compound isolated from the marine-derived fungus Penicillium oxalicum. No studies on the anti-tumor effect of this compound have been reported, except for a few focusing on its bactericidal properties. In this study, we found iso-PXA could stimulate P-gp ATPase activity and attenuate P-gp expression to increase the intracellular drug concentration in the cervical vincristine (VCR)-resistant cell line HeLa/VCR. Then, it increased ROS generation, depolarized MMP, promoted the release of cytochrome c from mitochondria, and further activated caspase-9, caspase-3 and PARP to induce cell apoptosis effectively through the intrinsic pathway. Caspase-8 medicated cleavage of Bid into the truncated form tBid partially initiated the mitochondrial apoptotic events. The elevation of the Bax/Bcl-2 ratio, the accumulation of FBW7 and the degradation of Mcl-1 accelerated the iso-PXA induced apoptotic process. The HeLa/VCR cell xenograft model again confirmed that iso-PXA had much better efficacy than vincristine in vivo. Taken together, these findings demonstrated that iso-PXA elicited remarkable anti-tumor and anti-MDR activity through inhibiting P-gp expression and function and re-activating the intrinsic apoptosis pathway in vitro and in vivo, suggesting it as a potential chemotherapeutic lead compound in the treatment of cervical MDR cancers.
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Nitrogen fertilization could improve the efficiency of Cd phytoextraction in contaminated soil and thus shorten the remediation time. However, limited information is available on the effect of N form on Cd phytoextraction and associated mechanisms in plants. This study examined the effect of N form on Cd accumulation, translocation, and speciation in Carpobrotus rossii and Solanum nigrum Plants were grown in nutrient solution with 5-15 µM Cd in the presence of 1000 µM NH4 (+) or NO3 (-) Plant growth and Cd uptake were measured, and Cd speciation was analyzed using synchrotron-based X-ray absorption spectroscopy. Shoot Cd accumulation was 30% greater with NH4 (+) than NO3 (-) supply. Carpobrotus rossii accumulated three times more Cd than S. nigrum. However, Cd speciation in the plants was not influenced by N form, but it did vary with species and tissues. In C. rossii, up to 91% of Cd was bound to S-containing ligands in all tissues except the xylem sap where 87-95% were Cd-OH complexes. Furthermore, the proportion of Cd-S in shoots was substantially lower in S. nigrum (44-69%) than in C. rossii (60-91%). It is concluded that the application of NH4 (+) (instead of NO3 (-)) increased shoot Cd accumulation by increasing uptake and translocation, rather than changing Cd speciation, and is potentially an effective approach for increasing Cd phytoextraction.
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Aizoaceae/metabolismo , Compostos de Amônio/farmacologia , Cádmio/metabolismo , Oxazinas/farmacologia , Solanum nigrum/metabolismo , Absorciometria de Fóton , Aizoaceae/química , Aizoaceae/efeitos dos fármacos , Cádmio/análise , Recuperação e Remediação Ambiental/métodos , Brotos de Planta/química , Solanum nigrum/química , Solanum nigrum/efeitos dos fármacosRESUMO
Non-target effects of two varieties of Bacillus thuringiensis (Bt)-maize straw (5422Bt1 [event Bt11] and 5422CBCL [MON810]) return on the Eisenia fetida were investigated by using multilevel assessments, compared to near-isogenic non-Bt-maize (5422). 5422Bt1 straw return had no deleterious effects on adult earthworms and had significantly positive effects on juveniles over three generations. Negative, no, and positive effects on adults treated with 5422CBCL straw were observed in the 1st, 2nd and 3rd generation, respectively. Negative and positive effects were observed on juveniles produced from the 1st- and 2nd-generation adults treated with 5422CBCL straw, respectively. Glutathione peroxidase activity of earthworms from Bt-maize treatments was significantly higher than that of control on the 90th d. Translationally controlled tumour protein (TCTP) and superoxide dismutase (SOD) genes were down-regulated, while annetocin (ANN) expression was up-regulated in 5422Bt1 treatments. TCTP and SOD genes were up-regulated, while ANN and heat shock protein 70 were down-regulated in E. fetida from 5422CBCL treatments. Enzyme-linked immunosorbent assay revealed that Cry1Ab released from 5422Bt1 and 5422CBCL straw degraded rapidly on the 15th and 30th d and had a slow decline in the rest testing time. Cry1Ab concentrations in the soil, casts and guts of earthworm significantly decreased over the course of the experiment. This study was the first to evaluate generational effects of Bt-maize straw return on earthworms under laboratory conditions. The responses of enzymes activity and genes expression may contribute to better understand above different effects of Bt-maize straw return on earthworms from the 1st generation.