RESUMO
Infecting a wide range of hosts, members of Reovirales (formerly Reoviridae) consist of a genome with different numbers of segmented double stranded RNAs (dsRNA) encapsulated by a proteinaceous shell and carry out genome replication and transcription inside the virion. Several cryo-electron microscopy (cryo-EM) structures of reoviruses with 9, 10 or 11 segmented dsRNA genomes have revealed insights into genome arrangement and transcription. However, the structure and genome arrangement of 12-segmented Reovirales members remain poorly understood. Using cryo-EM, we determined the structure of mud crab reovirus (MCRV), a 12-segmented dsRNA virus that is a putative member of Reovirales in the non-turreted Sedoreoviridae family, to near-atomic resolutions with icosahedral symmetry (3.1 Å) and without imposing icosahedral symmetry (3.4 Å). These structures revealed the organization of the major capsid proteins in two layers: an outer T = 13 layer consisting of VP12 trimers and unique VP11 clamps, and an inner T = 1 layer consisting of VP3 dimers. Additionally, ten RNA dependent RNA polymerases (RdRp) were well resolved just below the VP3 layer but were offset from the 5-fold axes and arranged with D5 symmetry, which has not previously been seen in other members of Reovirales. The N-termini of VP3 were shown to adopt four unique conformations; two of which anchor the RdRps, while the other two conformations are likely involved in genome organization and capsid stability. Taken together, these structures provide a new level of understanding for capsid stabilization and genome organization of segmented dsRNA viruses.
Assuntos
Orthoreovirus , Vírus de RNA , Reoviridae , Proteínas do Capsídeo/genética , Capsídeo , Microscopia Crioeletrônica , Reoviridae/genéticaRESUMO
Silicon is regarded as the most promising candidate due to its ultrahigh theoretical energy density (4200 mAh g-1). However, the large volume expansion of silicon nanoparticles would result in the destruction of electrodes and a shortened cycle lifetime. Here, inspired by the natural structure of bamboo, the silicon anode with vascular bundle-like structure is proposed to improve the electrochemical performance for the first time. The dense channel wall in the silicon anode can accommodate the volume change of silicon nanoparticles and the transport of ions and electrons is also enhanced. The obtained silicon anodes display excellent mechanical properties (50% compression resilience and the average peel force of 4.34 N) and good wettability. What more, the silicon anodes exhibit high initial coulombic efficiency (94.5%), excellent cycle stability (2100 mAh g-1 after 300 cycles) which stands out among the silicon anodes. Specially, the silicon anode with impressive areal capacity of 36.36 mAh cm-2 and initial coulombic efficiency of 84% is also achieved. This work offers a novel and efficient strategy for the preparation of the flexible electrodes with outstanding performance.
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Non-precious metal-based nitrogen-doped carbon (M-Nx/C) shows great potential as a substitute for precious metal Pt-based catalysts. However, the conventional pyrolytic methods for forming M-Nx/C active sites are prone to issues such as the lack of synergistic interactions among bimetallic atoms and the potential encasement of active sites, leading to compromised catalytic efficiency and hindered mass transfer. In this work, a highly active FeCo-N-C@U-AC electrocatalyst is developed with a high density of active sites, adequate exposure of catalytic sites, and robust mass transfer capability using the chemical vapor-phase deposition (CVD) technique. The resulting catalyst demonstrates impressive oxygen reduction reaction (ORR) catalytic performance and stability, with half-wave potentials of 0.820 V (0.1 M HClO4) and 0.911 V (0.1 M KOH), respectively. It also exhibits significantly enhanced stability, retaining 93.25% and 98.38% of current after continuous 50 000 s of durability testing, surpassing the retention rates of Pt/C (80.31% in HClO4 and 84.96% in KOH electrolytes). Notably, when employed as a cathode catalyst in proton exchange membrane fuel cells (PEMFCs) and zinc-air flow batteries (ZAFBs), the FeCo-N-C@U-AC catalyst delivers peak power densities of 859 and 162 mW·cm-2, respectively, showcasing competitive performance comparable to benchmark Pt/C.
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The increasing use of titanium dioxide (TiO2) nanoparticles (NPs) has raised concern about the safety of food additive TiO2. TiO2 has been considered no longer safe by EFSA due to concerns over genotoxicity, however, there are conflicting opinions upon the safety of TiO2 as a food additive, and the number of in vivo genotoxicity studies conducted on food additive TiO2 was limited. In order to investigate the potential genotoxicity of food additive TiO2, we evaluated the genotoxicity of a commercial food additive TiO2 (average size of 135.54 ± 41.01 nm, range from 60.83 to 230.16 nm, NPs account for 30% by number) using a battery of standard in vivo tests, including mammalian erythrocyte micronucleus test, mammalian bone marrow chromosomal aberration test and in vivo mammalian alkaline comet test. After 15 days of consecutive intragastric administration at doses of 250, 500, and 1000 mg/kgBW, food additive TiO2 neither increased the frequencies of bone marrow micronuclei or chromosomal aberration in mice, nor induced DNA strand breakage in rat liver cells. These results indicate that under the condition of this study, food additive TiO2 does not have genotoxic potential although it contains a fraction of NPs.
Assuntos
Nanopartículas Metálicas , Nanopartículas , Ratos , Camundongos , Animais , Aditivos Alimentares/toxicidade , Dano ao DNA , Testes para Micronúcleos , Titânio/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Ensaio Cometa , MamíferosRESUMO
Mosquito viruses cause unpredictable outbreaks of disease. Recently, several unassigned viruses isolated from mosquitoes, including the Omono River virus (OmRV), were identified as totivirus-like viruses, with features similar to those of the Totiviridae family. Most reported members of this family infect fungi or protozoans and lack an extracellular life cycle stage. Here, we identified a new strain of OmRV and determined high-resolution structures for this virus using single-particle cryo-electron microscopy. The structures feature an unexpected protrusion at the five-fold vertex of the capsid. Disassociation of the protrusion could result in several conformational changes in the major capsid. All these structures, together with some biological results, suggest the protrusions' associations with the extracellular transmission of OmRV.
Assuntos
Microscopia Crioeletrônica/métodos , Vírus de RNA de Cadeia Dupla/ultraestrutura , Proteínas Estruturais Virais/ultraestrutura , Aedes/virologia , AnimaisRESUMO
Citrate-based polymers are commonly used to create biodegradable implants. In an era of personalized medicine, it is highly desired that the degradation rates of citrate-based implants can be artificially regulated as required during clinical applications. Unfortunately, current citrate-based polymers only undergo passive degradation, which follows a specific degradation profile. This presents a considerable challenge for the use of citrate-based implants. To address this, a novel citrate-based polyester elastomer (POCSS) with artificially regulatable degradation rate is developed by incorporating disulfide bonds (S-S) into the backbone chains of the crosslinking network of poly(octamethylene citrate) (POC). This POCSS exhibits excellent and tunable mechanical properties, notable antibacterial properties, good biocompatibility, and low biotoxicity of its degradation products. The degradation rate of the POCSS can be regulated by breaking the S-S in its crosslinking network using glutathione (GSH). After a period of subcutaneous implantation of POCSS scaffolds in mice, the degradation rate eventually increased by 2.46 times through the subcutaneous administration of GSH. Notably, we observed no significant adverse effects on its surrounding tissues, the balance of the physiological environment, major organs, and the health status of the mice during degradation.
Assuntos
Elastômeros , Poliésteres , Camundongos , Animais , Elastômeros/química , Poliésteres/química , Ácido Cítrico , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Engenharia Tecidual , Polímeros/química , Citratos/químicaRESUMO
A large group of polyhalogenated compounds has been added to the list of persistent organic pollutants in a global convention endorsed by over 100 nations. Once entering the biotas, these pollutants are transported to focal sites of toxicological action and affected endogenous metabolites, which exhibited distinct tissue or organ distribution patterns. However, no study is available to achieve simultaneous mapping of the spatial distributions of xenobiotics and endogenous metabolites for clarifying the molecular mechanism of toxicities. Herein, we present a sensitive mass spectrometry imaging methodâtetraphenyl phosphonium chloride-enhanced ionization coupled with air flow-assisted ionization-Orbitrap mass spectrometryâwhich simultaneously determined the spatial distributions of polyhalogenated xenobiotics and endogenous metabolites. The spatially resolved toxicokinetics and toxicodynamics of typical polyhalogenated compounds (chlorinated paraffins (CPs) and hexabromocyclododecane (HBCD)) were assessed in zebrafish. Co-imaging of polyhalogenated compounds and metabolites visualized the major accumulation organs and maternal transfer of HBCD and CPs, and it clarified the reproductive toxicity of HBCD. CPs were accumulated in the liver, heart, and brain and decreased the concentrations of polyamine/inosine-related metabolites and lipid molecules in these organs. HBCD accumulated in the ovary and was effectively transferred to eggs, and it also disrupted normal follicular development and impaired the production of mature eggs from the ovary by inhibiting expressions of the luteinizing hormone/choriogonadotropin receptor gene. The toxic effects of metabolic disruptions were validated by organ-specific histopathological examinations. These results highlight the necessity to assess the distributions and bioeffects of pollutants in a spatial perspective.
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Poluentes Ambientais , Xenobióticos , Animais , Feminino , Xenobióticos/metabolismo , Peixe-Zebra , Espectrometria de Massas , Fígado/metabolismoRESUMO
Mounting evidence has shown that ambient PM2.5 exposure is closely associated with the development of obesity, and adipose tissue represents an important endocrine target for PM2.5. In this study, the 3T3-L1 preadipocyte differentiation model was employed to comprehensively explore the adipogenic potential of PM2.5. After 8 days of PM2.5 exposure, adipocyte fatty acid uptake and lipid accumulation were significantly increased, and adipogenic differentiation of 3T3-L1 cells was promoted in a concentration-dependent manner. Transcriptome and lipidome analyses revealed the systematic disruption of transcriptional and lipid profiling at 10 µg/mL PM2.5. Functional enrichment and visualized network analyses showed that the peroxisome proliferator-activated receptor (PPAR) pathway and the metabolism of glycerophospholipids, glycerolipids, and sphingolipids were most significantly affected during adipocyte differentiation. Reporter gene assays indicated that PPARγ was activated by PM2.5, demonstrating that PM2.5 promoted adipogenesis by activating PPARγ. The increased transcriptional and protein expressions of PPARγ and downstream adipogenesis-associated markers (e.g., Fabp4 and CD36) were further cross-validated using qRT-PCR and western blot. PM2.5-induced adipogenesis, PPARγ pathway activation, and lipid remodeling were significantly attenuated by the supplementation of a PPARγ antagonist (T0070907). Overall, this study yielded mechanistic insights into PM2.5-induced adipogenesis in vitro by identifying the potential biomolecular targets for the prevention of PM2.5-induced obesity and related metabolic diseases.
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Adipogenia , PPAR gama , Animais , Camundongos , PPAR gama/genética , PPAR gama/metabolismo , Células 3T3-L1 , Lipídeos , Obesidade , Diferenciação CelularRESUMO
Tough and self-healable substrates can enable stretchable electronics long service life. However, for substrates, it still remains a challenge to achieve both high toughness and autonomous self-healing ability at room temperature. Herein, a strategy by using the combined effects between quadruple H-bonding and slidable cross-links is proposed to solve the above issues in the elastomer. The elastomer exhibits high toughness (77.3â MJ m-3 ), fracture energy (≈127.2â kJ m-2 ), and good healing efficiency (91 %) at room temperature. The superior performance is ascribed to the inter and intra crosslinking structures of quadruple H-bonding and polyrotaxanes in the dual crosslinking system. Strain-induced crystallization of PEG in polyrotaxanes also contributes to the high fracture energy of the elastomers. Furthermore, based on the dual cross-linked supramolecular elastomer, a highly stretchable and self-healable electrode containing liquid metal is also fabricated, retaining resistance stability (0.16-0.26â Ω) even at the strain of 1600 %.
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Rotaxanos , Cristalização , Elastômeros , Eletrodos , EletrônicaRESUMO
Timely restoration of blood supply after myocardial ischemia is imperative for the treatment of acute myocardial infarction but causes additional myocardial ischemia/reperfusion (MI/R) injury, which has not been hitherto effectively targeted by interventions for MI/R injury. Hence, the development of advanced nanomedicine that can reduce apoptosis of cardiomyocytes while protecting against MI/R in vivo is of utmost importance. Herein, a redox-responsive and emissive TPE-ss covalent organic framework (COF) nanocarrier by integrating aggregation-induced emission luminogens and redox-responsive disulfide motifs into the COF skeleton is developed. TPE-ss COF allows for efficient loading and delivery of matrine, a renowned anti-cryptosporidial drug, which significantly reduces MI/R-induced functional deterioration and cardiomyocyte injury when injected through the tail vein into MI/R models at 5 min after 30 min of ischemia. Moreover, TPE-ss COF@Matrine shows a drastic reduction in cardiomyocyte apoptosis and improvements in cardiac function and survival rate. The effect of the TPE-ss COF carrier is further elucidated by enhanced cardiomyocyte viability and triphenyltetrazolium chloride staining in vitro. This work demonstrates the cardioprotective effect of TPE-ss COFs for MI/R injury, which unleashes the immense potential of using COFs as smart drug carriers for the peri-reperfusion treatment of ischemic heart disease with low cost, high stability, and single postoperative intervention.
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Estruturas Metalorgânicas , Traumatismo por Reperfusão Miocárdica , Humanos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Estruturas Metalorgânicas/farmacologia , Miócitos Cardíacos , Apoptose , OxirreduçãoRESUMO
The demand for stretchable electronics with a broader working range is increasing for wide application in wearable sensors and e-skin. However, stretchable conductors based on soft elastomers always exhibit low working range due to the inhomogeneous breakage of the conductive network when stretched. Here, a highly stretchable and self-healable conductor is reported by adopting polyrotaxane and disulfide bonds into the binding layer. The binding layer (PR-SS) builds the bridge between polymer substrates (PU-SS) and silver nanowires (AgNWs). The incorporation of sliding molecules endows the stretchable conductor with a long sensing range (190%) due to the energy dissipation derived from the sliding nature of polyrotaxanes, which is two times higher than the working range (93%) of conductors based on AP-SS without polyrotaxanes. Furthermore, the mechanism of sliding effect for the polyrotaxanes in the elastomers is investigated by SEM for morphological change of AgNWs, in situ small-angle x-ray scattering, as well as stress relaxation experiments. Finally, human-body-related sensing tests and a self-correction system in fitness are designed and demonstrated.
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Ciclodextrinas , Rotaxanos , Elastômeros/química , Condutividade Elétrica , Humanos , Polímeros/químicaRESUMO
As a biodegradable elastomer, poly(1,8-octanediol-co-citrate) (POC) has been widely applied in tissue engineering and implantable electronics. However, the unclear degradation mechanism has posed a great challenge for the better application and development of POC. To reveal the degradation mechanism, here, we present a systematic investigation into in vivo and in vitro degradation behaviors of POC. Initially, critical factors, including chemical structures, hydrophilic and water-absorbency characteristics, and degradation reaction of POC, are investigated. Then, various degradation-induced changes during in vitro degradation of POC-x (POC with different cross-linking densities) are monitored and discussed. The results show that (1) cross-linking densities exponentially drop with degradation time; (2) mass loss and PBS-absorption ratio grow nonlinearly; (3) the morphology on the cross-section changes from flat to rough at a microscopic level; (4) the cubic samples keep swelling until they collapse into fragments from a macro view; and (5) the mechanical properties experience a sharp drop at the beginning of degradation. Finally, the in vivo degradation behaviors of POC-x are investigated, and the results are similar to those in vitro. The comprehensive assessment suggests that the in vitro and in vivo degradation of POC occurs primarily through bulk erosion. Inflammation responses triggered by the degradation of POC-x are comparable to poly(lactic acid), or even less obvious. In addition, the mechanical evaluation of POC in the simulated application environment is first proposed and conducted in this work for a more appropriate application. The degradation mechanism of POC revealed will greatly promote the further development and application of POC-based materials in the biomedical field.
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Ácido Cítrico , Elastômeros , Materiais Biocompatíveis/química , Citratos , Elastômeros/química , Teste de Materiais , Polímeros , ÁguaRESUMO
The present study aimed to evaluate the subchronic toxicity of feeding with phytase-transgenic maize line 11TPY050 in Sprague-Dawley (SD) rats. Rats (n = 10/sex/group) were fed with 12.5%, 25% or 50% (w/w) transgenic maize diet, 12.5%, 25% or 50% (w/w) non-transgenic isoline OSL940 maize diet, or 50% (w/w) commercially available Zhengdan958 maize diet for 90 days. Daily clinical observations and weekly measurements of body weights and food consumption were conducted. Blood samples were collected on day 46 and day 91 for hematology and clinical chemistry evaluations. At the end of the study, macroscopic and microscopic examinations were performed. No effects on body weight and food consumption were observed. The results of hematology, clinical chemistry, and absolute and relative organ weights in the transgenic maize group were comparable to those in the parental maize group. Several statistical differences were not dose-related and were not considered to be biologically significant. Furthermore, the terminal necropsy and histopathological examination showed no treatment-related changes among the groups. The results from the present 90-day feeding study of phytase-transgenic maize 11TPY050 indicated no unexpected adverse effects in SD rats. The phytase transgenic maize 11TPY050 has substantial equivalence with non-transgenic maize.
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6-Fitase/administração & dosagem , Plantas Geneticamente Modificadas/toxicidade , Zea mays/genética , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Feminino , Testes Hematológicos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Plantas Geneticamente Modificadas/enzimologia , Ratos , Ratos Sprague-DawleyRESUMO
PURPOSE: To evaluate the accuracy of pulmonary nodule (PN) detection in overweight or obese adult patients using ultralow-dose computed tomography (ULDCT) with tin filtration at 100 kV and advanced model-based iterative reconstruction (ADMIRE). METHODS: Eighty-one patients with body mass indices of ≥25 kg/m2 were enrolled. All patients underwent low-dose chest CT (LDCT), followed by ULDCT. Two radiologists experienced in LDCT established the standard of reference (SOR) for PNs. The number, type, size, and location of PNs were identified in the SOR. Effective dose, objective image quality (IQ), and subjective IQ based on two radiologists' scores were compared between ULDCT and LDCT. The detection performances of radiologists based on ULDCT were calculated according to the nodule analyses. Logistic regression was used to test for independent predictors of PN detection sensitivity. RESULTS: Both the effective dose and objective IQ were lower for ULDCT than for LDCT (both p < 0.001). Both radiologists rated the subjective IQ of the overall IQ on ULDCT to be diagnostically sufficient. In total, 234 nodules (mean diameter, 3.4 ± 1.9 mm) were classified into 32 subsolid, 149 solid, and 53 calcified nodules according to the SOR. The overall sensitivity of ULDCT for nodule detection was 93.6%. Based on multivariate analyses, the nodule types (p = 0.015) and sizes (p = 0.013) were independent predictors of nodule detection. CONCLUSIONS: Compared with LDCT, ULDCT with tin filtration at 100 kV and ADMIRE could significantly reduce the radiation dose in overweight or obese patients while maintaining good sensitivity for nodule detection.
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Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Adulto , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Obesidade/complicações , Sobrepeso , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estanho , Tomografia Computadorizada por Raios X/métodosRESUMO
BACKGROUND: The poor prognosis of esophageal squamous cell carcinoma (ESCC) highlights the need for novel strategies against this disease. Our previous study suggested the involvement of CCL2 and tumor associated macrophages (TAMs) in esophageal carcinogenesis. Despite the recognition of TAMs as a promising target for cancer treatment, mechanisms underlying its infiltration, activation and tumor-promotive function in ESCC remain unknown. METHODS: Human esophageal tissue array and TCGA database were used to evaluate the clinical relevance of CCL2 and TAMs in ESCC. F344 rats and C57BL/6 mice were treated with N-nitrosomethylbenzylamine (NMBA) to establish orthotopic models of esophageal carcinogenesis. CCL2/CCR2 gene knockout mice and macrophage-specific PPARG gene knockout mice were respectively used to investigate the role of infiltration and polarization of TAMs in ESCC. CCL2-mediated monocyte chemotaxis was estimated in malignantly transformed Het-1A cells. THP-1 cells were used to simulate TAMs polarization in vitro. RNA-sequencing was performed to uncover the mechanism. RESULTS: Increasing expression of CCL2 correlated with TAMs accumulation in esophageal carcinogenesis, and they both predicts poor prognosis in ESCC cohort. Animal studies show blockade of CCL2-CCR2 axis strongly reduces tumor incidence by hindering TAMs recruitment and thereby potentiates the antitumor efficacy of CD8+ T cells in the tumor microenvironment. More importantly, M2 polarization increases PD-L2 expression in TAMs, resulting in immune evasion and tumor promotion through PD-1 signaling pathway. CONCLUSION: This study highlights the role of CCL2-CCR2 axis in esophageal carcinogenesis. Our findings provide new insight into the mechanism of immune evasion mediated by TAMs in ESCC, suggesting the potential of TAMs-targeted strategies for ESCC prevention and immunotherapy.
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Biomarcadores Tumorais/metabolismo , Quimiocina CCL2/metabolismo , Neoplasias Esofágicas/imunologia , Carcinoma de Células Escamosas do Esôfago/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores CCR2/metabolismo , Macrófagos Associados a Tumor/imunologia , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Quimiocina CCL2/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Receptor de Morte Celular Programada 1/genética , Ratos , Ratos Endogâmicos F344 , Receptores CCR2/genética , Células Tumorais Cultivadas , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologiaRESUMO
OBJECTIVE: To establish an rat basophil leukemia(RBL)-2H3 cell line stably expressing human high affinity receptor containing alpha, beta and gamma chain(hFcεRIαßγ), in order to provide experimental materials for evaluating allergenicity of food. METHODS: The lentivirus was transfected into RBL-2H3 cells, and the mRNA expression of hFcεRIαßγ in cells was detected by real-time PCR and the protein expression of hFcεRIα was detected by flow cytometry. RESULTS: Sequencing result showed that recombinant lentiviral vector GV367-hFcεRIαßγ was successfully constructed. According to the result of experiments, lentivirus could effectively infect RBL-2H3 cells. The mRNA of hFcεRIαßγ and protein levels of hFcεRIα in RBL-2H3 cells were successfully overexpressed. CONCLUSION: The hFcεRIαßγ/RBL-2H3 cells were preliminarily constructed, which could be binded with human IgE and further used in the evaluation system of food allergy, compared to RBL-2H3 cells.
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Linhagem Celular , Hipersensibilidade Alimentar , Receptores de IgE/metabolismo , Animais , Humanos , Imunoglobulina E , Ratos , Células Tumorais CultivadasRESUMO
OBJECTIVE: To observe the steatosis and inflammatory effects of L02 hepatocytes induced by different concentrations of sodium oleate. METHODS: L02 cells were incubated with sodium oleate in different concentration for 24 h, and the cell viability was detected. L02 cells were respectively cultured with 75, 150, 300 µmol/L sodium oleate for 24 h. The lipid accumulation of the cells was observed by oil red staining. The content of triglyceride in the cells was detected, the IL-6 content in the cell supernatant was detected. The expression of SIRT1 and nuclear factor-κB(NF-κB) was detected by Western Blot. The expression of Toll-like receptor 2 and Toll-like receptor 4(TLR2 and TLR4) on the cell surface was detected by flow cytometry. RESULTS: With the increase of sodium oleate concentration, the cell viability decreased, the cell growth inhibition rate increased. The content of triglyceride in L02 cells treated with 75, 150 and 300 µmol/L sodium oleate was significantly higher than that in the control group(P<0. 01, P<0. 001, P<0. 001), the IL-6 in the supernate was significantly higher than that in the control group(P<0. 05, P<0. 01, P<0. 001). The result of oil red staining showed that the lipids in the cells were obviously accumulated after sodium oleate treatment. The expression of TLR2 in L02 cells treated with 150 and 300 µmol/L sodium oleate was significantly higher than that in the control group(P<0. 05, P<0. 001). There was no significant increase in TLR4 expression after sodium oleate intervention in L02 cells. The expression of SIRT1 protein in the sodium oleate group was lower than that in the control group, and the expression of NF-κB p65 was higher than that in the control group through Western Blot result. CONCLUSION: L02 hepatocyte steatosis caused by sodium oleate may be associated with TLR2/NF-κB mediated inflammatory pathway.
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Fígado Gorduroso , Hepatócitos , Humanos , Inflamação , NF-kappa B , Ácido OleicoRESUMO
This study evaluated the subchronic toxicity of cerium nitrate and determined the no observed adverse effect level (NOAEL) in Wistar rats. In accordance with the Organization for Economic Co-operation and Development guidelines, cerium nitrate was orally administered to Wistar rats by gavage at 0, 0.2, 75, 150, and 300â¯mg/kgâ¯bw/day for 90 days, followed by 28 days of recovery period in the 300â¯mg/kgâ¯bw/day and the control groups. The following parameters were evaluated: mortality, abnormalities, body weight, food consumption, hematology, serum biochemistry, urinanalysis, gross necropsy and histopathology. At the end of the treatment, several significant changes were observed in the 300â¯mg/kgâ¯bw/day groups: relatively decreased mean body weight of males, increased LYMPH%, RET% and decreased NEUT%, RBC of the females, increased ALT, AST and decreased ALB, T-Bil, CHO, CK, LDH of males. Significantly decreased T-Bil, CHO, CK and LDH were also observed in males of the 150â¯mg/kgâ¯bw/day group. Pathological examination revealed that the incidences of foreign body granulomatous lesions in lungs were higher in the 150 and 300â¯mg/kgâ¯bw/day groups as compared with the control group. These findings were attributed to unexpected gavage exposure because the granuloma exhibited a bronchiole-derived distribution. Taken together, the NOAEL of cerium nitrate in Wistar rats is set to be 75â¯mg/kgâ¯bw/day in the present study.
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Cério/toxicidade , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Contagem de Células , Feminino , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Nível de Efeito Adverso não Observado , Ratos Wistar , Testes de Toxicidade SubcrônicaRESUMO
To date, many safety assessments of genetically modified (GM) food have been done, but there was still considerable skepticism about the safety of genetic modified foods because no study could be designed to discover all of the potential effects. Since behavioral endpoints could provide one of the most sensitive strategies to reveal subtle functional deficits. In the present study, behavioral profiles in mice fed with milk derived from human lactoferrin gene-modified cows were investigated to enrich the toxicological data of GM food. Conventional milk and GM milk were added to diets at a proportion of 7.5%, 15% and 30%(w/w). After the mice consuming different diets for 30 days, a battery of behavioral tests were conducted to evaluate motor, sensory and cognitive functions. No significant differences were observed in spontaneous activity, grip strength and nociception between the treatment groups. And animals of different groups exhibited similar performance in rotarod, dark box, step-down and MORRIS water maze task. The study suggested that mice fed with conventional milk or human lactoferrin gene-modified milk had similar motor, sensory and cognitive functions.
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Ração Animal/análise , Comportamento Animal , Suplementos Nutricionais , Lactoferrina/genética , Leite/química , Animais , Peso Corporal , Bovinos , Feminino , Humanos , Lactoferrina/metabolismo , Camundongos , Camundongos EndogâmicosRESUMO
Benchmark dose (BMD) analysis is generally recognized superior to generate a point of departure (PoD) to conduct risk assessment on environmental toxicants, comparing with the traditionally employed no observed adverse effect level (NOAEL) or lowest observed adverse effect level (LOAEL) methods. However, only a few studies compared the two on producing PoD of thyroid toxicity caused by environmental chemicals. Here, we presented BMD analyses on several thyroid toxicity endpoints caused by a model chemical - propylthiouracil (PTU). Adult female rats underwent ovariectomy were randomly assigned into groups receiving different doses of PTU (0, 0.1, 0.5, 1.0, and 5.0â¯mg/kg bw) through gavage for 8 days. Results show that PTU induces significant dose-dependent changes of serum total thyroxine (tT4), total triiodothyronine (tT3), thyroid stimulating hormones, liver type I 5'-deiodinonase (5'-DI) and malic enzyme (ME) activity with profound histopathological exacerbation. BMD and BMDL results (0.03 and 0.01â¯mg/kg bw respectively) from Hill model of liver 5'-DI activity were accepted based on selection criteria in the benchmark dose analysis. In summary, BMD analysis results in much lower PoD (0.01â¯mg/kg bw) than LOAEL (0.1â¯mg/kg bw) in PTU induced thyroid toxicity.