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Cholesterol is a vital component of the central nervous system and tissues, and understanding its spatial distribution is crucial for biology, pathophysiology, and diagnostics. However, direct imaging of cholesterol using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) remains challenging and time-consuming due to the difficulty in ionizing the sterol molecule. To tackle this issue, a MALDI-MSI method is established for direct and rapid analysis of the spatial distribution of cholesterol in Alzheimer's disease (AD), different cancer tissues and organs via MALDI-MSI. This excellent imaging performance depends on the study and systemic optimization of various conditions that affect the imaging of MALDI-MSI. In this case, we report the distribution and levels of cholesterol across specific structures of the AD mouse brain and different tumor tissue and organs. According to the results, the content of cholesterol in the AD mouse cerebellum, especially in the arborvitae, was significantly higher than that in the wild type (WT) model. Furthermore, we successfully visualize the distribution of cholesterol in other organs, such as the heart, liver, spleen, kidney, pancreas, as well as tumor tissues parenchyma and interstitium using MALDI-MSI. Notably, the attribution of cholesterol MS/MS hydrocarbon fragments was systematically investigated. Our presented optimization strategy and established MALDI-MSI method can be easily generalized for different animal tissues or live samples, thereby facilitating the potential for applications of MALDI-MSI in clinical, medical and biological research.
Asunto(s)
Enfermedad de Alzheimer , Colesterol , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Colesterol/análisis , Colesterol/metabolismo , Ratones , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Ratones Endogámicos C57BL , Neoplasias/diagnóstico por imagen , Neoplasias/metabolismo , Neoplasias/química , Ratones Transgénicos , Modelos Animales de Enfermedad , HumanosRESUMEN
Methamphetamine (METH) is the second abused drug which affects abusers' health and induces social crimes, developing novel methods with high sensitivity and selectivity for METH detecting is still challenging. In this paper, a colorimetric and fluorescent dual-channel sensor for METH has been constructed. We combine the enzyme-mimic catalytic activity of gold nanoparticles (GNPs) with high target specificity of METH aptamer to create a nanosensor (Apt-GNP), in the presence of METH, the absorption of 3,3',5,5'-tetramethylbenzidine (OxTMB) at 650 nm enhanced with METH concentration increasing, while the absorption characteristic peak of GNPs at 530 nm remained almost unchanged. The ratio of A650nm/A530nm and METH concentration had a good linear relationship when METH concentration was in the range of 5-50 µM, and the corresponding linear equation is A650nm/A530nm = 0.00727CMETH (µM) + 0.783 with R2 = 0.997 and LOD = 0.40 µM (LOD = 3σ/s, n = 11). Interestingly, the fluorescence emission of Rhodamine B (RB) overlaps with the absorption spectrum of OxTMB which represents the content of METH and the fluorescence signal of RB can be quenched through internal filtering effect (IEF). Hence, when RB was doped to the detection system, the decay of RB fluorescence can reflect the concentrations change of METH. Accordingly, the linear equation is F/FR = -0.00751CMETH (µM) + 0.895 with R2 = 0.993 and LOD = 0.40 µM, where F was the fluorescence of the analytical solution at 580 nm with METH and FR was fluorescence of RB control solution. The dual-channel sensor can measure METH in serum and artificial urine successfully which is potential to be applied in drug-using crime sites and provide direct evidence to law enforcement officials.
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Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single-atom-decorated CdS (Ni1-CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1-CdS/WO3 attained a urea yield rate of 78â µM h-1 and an apparent quantum yield of 0.15 % at 385â nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by â OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions.
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Irradiation (IR) induces immunogenic cell death (ICD) in tumors, but it rarely leads to the abscopal effect (AE); even combining IR with immune checkpoint inhibitors has shown only anecdotal success in inducing AEs. In this study, we aimed to enhance the IR-induced immune response and generate reproducible AEs using the anti-alcoholism drug, disulfiram (DSF), complexed with copper (DSF/Cu) to induce tumor ICD. We measured ICD in vitro and in vivo. In mouse tumor models, DSF/Cu was injected intratumorally followed by localized tumor IR, creating an in situ cancer vaccine. We determined the anticancer response by primary tumor rejection and assessed systemic immune responses by tumor rechallenge and the occurrence of AEs relative to spontaneous lung metastasis. In addition, we analyzed immune cell subsets and quantified proinflammatory and immunosuppressive chemokines/cytokines in the tumor microenvironment (TME) and blood of the vaccinated mice. Immune cell depletion was investigated for its effects on the vaccine-induced anticancer response. The results showed that DSF/Cu and IR induced more potent ICD under hypoxia than normoxia in vitro. Low-dose intratumoral (i.t.) injection of DSF/Cu and IR(12Gy) demonstrated strong anti-primary and -rechallenged tumor effects and robust AEs in mouse models. These vaccinations also increased CD8+ and CD4+ cell numbers while decreasing Tregs and myeloid-derived suppressor cells in the 4T1 model, and increased CD8+, dendritic cells (DC), and decreased Treg cell numbers in the MCa-M3C model. Depleting both CD8+ and CD4+ cells abolished the vaccine's anticancer response. Moreover, vaccinated tumor-bearing mice exhibited increased TNFα levels and reduced levels of immunosuppressive chemokines/cytokines. In conclusion, our novel approach generated an anticancer immune response that results in a lack of or low tumor incidence post-rechallenge and robust AEs, i.e., absence of or decreased spontaneous lung metastasis in tumor-bearing mice. This approach is readily translatable to clinical settings and may increase IR-induced AEs in cancer patients.
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Neoplasias de la Mama , Vacunas contra el Cáncer , Cobre , Disulfiram , Muerte Celular Inmunogénica , Disulfiram/farmacología , Animales , Vacunas contra el Cáncer/farmacología , Vacunas contra el Cáncer/inmunología , Femenino , Ratones , Muerte Celular Inmunogénica/efectos de los fármacos , Cobre/farmacología , Humanos , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Microambiente Tumoral/efectos de los fármacos , Ratones Endogámicos BALB CRESUMEN
A jamming phase diagram maps the phase states of granular materials to their intensive properties such as shear stress and density (or packing fraction). We investigate how different phases in a jamming phase diagram of granular materials are related to their fabric structure via three-dimensional discrete element method simulations. Constant-volume quasi-static simple shear tests ensuring uniform shear strain field are conducted on bi-disperse spherical frictional particles. Specimens with different initial solid fractions are sheared until reaching steady state at a large shear strain (200%). The jamming threshold in terms of stress, non-rattler fraction, and coordination numbers (Z's) of different contact networks is discussed. The evolution of fabric anisotropy (F) of each contact network during shearing is also examined. By plotting the fabric data in the F-Z space, a unique critical fabric surface (CFS) becomes apparent across all specimens, irrespective of their initial phase states. Through the correlation of this CFS with fabric signals corresponding to jamming transitions, we introduce a novel jamming phase diagram in the fabric F-Z space, offering a convenient approach to distinguish the various phases of granular materials solely through the direct observation of geometrical arrangements of particles. This jamming phase diagram underscores the importance of the microstructure underlying the conventional jamming phenomenon and introduces a novel standpoint for interpreting the phase transitions of granular materials that have been exposed to processes such as compaction, shearing, and other complex loading histories.
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Most of the traditional matrices cannot simultaneously image multiple lipids and phytohormones, so screening and discovery of novel matrices stand as essential approaches for broadening the application scope of matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). In this work, 12 organic small molecule compounds were comprehensively screened and investigated as potential MALDI matrices for simultaneous imaging analysis of various lipids and phytohormones. In the positive ionization mode, p-nitroaniline, m-nitroaniline, and 2-aminoterephthalic acid displayed good performance for the highly sensitive detection of lysophosphatidylcholines (LPCs), phosphatidylcholines (PCs), and triacylglycerols (TGs). Furthermore, p-nitroaniline possessed excellent characteristics of strong ultraviolet absorption and homogeneous cocrystallization, making it a desirable matrix for MALDI-MSI analysis of eight plant hormones. Compared with conventional matrices (2,5-dihydroxybenzoic acid (DHB), α-cyano-4-hydroxycinnamic acid (CHCA), and 9-aminoacridine (9-AA), the use of p-nitroaniline resulted in higher ionization efficiency, superior sensitivity, and clearer imaging images in dual polarity mode. Our research offers valuable guidance and new ideas for future endeavors in matrix screening.
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Compuestos de Anilina , Diagnóstico por Imagen , Reguladores del Crecimiento de las Plantas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Lípidos/análisisRESUMEN
In situ transcriptomic techniques promise a holistic view of tissue organization and cell-cell interactions. There has been a surge of multiplexed RNA in situ mapping techniques but their application to human tissues has been limited due to their large size, general lower tissue quality and high autofluorescence. Here we report DART-FISH, a padlock probe-based technology capable of profiling hundreds to thousands of genes in centimeter-sized human tissue sections. We introduce an omni-cell type cytoplasmic stain that substantially improves the segmentation of cell bodies. Our enzyme-free isothermal decoding procedure allows us to image 121 genes in large sections from the human neocortex in <10 h. We successfully recapitulated the cytoarchitecture of 20 neuronal and non-neuronal subclasses. We further performed in situ mapping of 300 genes on a diseased human kidney, profiled >20 healthy and pathological cell states, and identified diseased niches enriched in transcriptionally altered epithelial cells and myofibroblasts.
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Perfilación de la Expresión Génica , ARN , Humanos , ARN/genética , Hibridación in Situ , Perfilación de la Expresión Génica/métodos , Transcriptoma , CitosolRESUMEN
Catalytic conversion of nitrate (NO3-) pollutants into ammonia (NH3) offers a sustainable and promising route for both wastewater treatment and NH3 synthesis. Alkali cations are prevalent in nitrate solutions, but their roles beyond charge balance in catalytic NO3- conversion have been generally ignored. Herein, we report the promotion effect of K+ cations in KNO3 solution for NO3- reduction over a TiO2-supported Ni single-atom catalyst (Ni1/TiO2). For photocatalytic NO3- reduction reaction, Ni1/TiO2 exhibited a 1.9-fold NH3 yield rate with nearly 100% selectivity in KNO3 solution relative to that in NaNO3 solution. Mechanistic studies reveal that the K+ cations from KNO3 gradually bonded with the surface of Ni1/TiO2, in situ forming a K-O-Ni moiety during reaction, whereas the Na+ ions were unable to interact with the catalyst in NaNO3 solution. The charge accumulation on the Ni sites induced by the incorporation of K atom promoted the adsorption and activation of NO3-. Furthermore, the K-O-Ni moiety facilitated the multiple proton-electron coupling of NO3- into NH3 by stabilizing the intermediates.
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Targeted spatial transcriptomics hold particular promise in analyzing complex tissues. Most such methods, however, measure only a limited panel of transcripts, which need to be selected in advance to inform on the cell types or processes being studied. A limitation of existing gene selection methods is their reliance on scRNA-seq data, ignoring platform effects between technologies. Here we describe gpsFISH, a computational method performing gene selection through optimizing detection of known cell types. By modeling and adjusting for platform effects, gpsFISH outperforms other methods. Furthermore, gpsFISH can incorporate cell type hierarchies and custom gene preferences to accommodate diverse design requirements.
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Perfilación de la Expresión Génica , Técnicas Genéticas , Análisis de la Célula Individual , Transcriptoma , Análisis de Secuencia de ARNRESUMEN
BACKGROUND: Despite therapeutic advances, once a cancer has metastasized to the bone, it represents a highly morbid and lethal disease. One third of patients with advanced clear cell renal cell carcinoma (ccRCC) present with bone metastasis at the time of diagnosis. However, the bone metastatic niche in humans, including the immune and stromal microenvironments, has not been well-defined, hindering progress towards identification of therapeutic targets. METHODS: We collected fresh patient samples and performed single-cell transcriptomic profiling of solid metastatic tissue (Bone Met), liquid bone marrow at the vertebral level of spinal cord compression (Involved), and liquid bone marrow from a different vertebral body distant from the tumor site but within the surgical field (Distal), as well as bone marrow from patients undergoing hip replacement surgery (Benign). In addition, we incorporated single-cell data from primary ccRCC tumors (ccRCC Primary) for comparative analysis. RESULTS: The bone marrow of metastatic patients is immune-suppressive, featuring increased, exhausted CD8 + cytotoxic T cells, T regulatory cells, and tumor-associated macrophages (TAM) with distinct transcriptional states in metastatic lesions. Bone marrow stroma from tumor samples demonstrated a tumor-associated mesenchymal stromal cell population (TA-MSC) that appears to be supportive of epithelial-to mesenchymal transition (EMT), bone remodeling, and a cancer-associated fibroblast (CAFs) phenotype. This stromal subset is associated with poor progression-free and overall survival and also markedly upregulates bone remodeling through the dysregulation of RANK/RANKL/OPG signaling activity in bone cells, ultimately leading to bone resorption. CONCLUSIONS: These results provide a comprehensive analysis of the bone marrow niche in the setting of human metastatic cancer and highlight potential therapeutic targets for both cell populations and communication channels.
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Carcinoma de Células Renales , Humanos , Carcinoma de Células Renales/genética , Células del Estroma/patología , Transducción de Señal , Perfilación de la Expresión Génica , Análisis de la Célula Individual , Microambiente TumoralRESUMEN
Sodium montmorillonite (Na-MMT) clay mineral is a common type of swelling clay that has potential applications for nuclear waste storage at high temperatures and pressures. However, there is a limited understanding of the mechanical properties, local molecular stiffness, and dynamic heterogeneity of this material at elevated temperatures and pressures. To address this, we employ all-atomistic (AA) molecular dynamics (MD) simulation to investigate the tensile behavior of Na-MMT clay over a wide temperature range (500 K to 1700 K) and pressures (200 atm to 100 000 atm). The results show that increasing the temperature significantly reduces the tensile modulus, strength, and failure strain, while pressure has a minor effect compared to temperature, as seen in the normalized pressure-temperature plot. Mean-square displacement (MSD) analysis reveals increased molecular stiffness with increasing pressure and decreasing temperature, indicating suppressed atomic mobility. Our simulations indicate temperature-dependent dynamical heterogeneity in the Na-MMT model, supported by experimental studies and quantified local molecular stiffness distribution. These findings enhance our understanding of the tensile response and dynamical heterogeneity of Na-MMT clay under extreme conditions, aiding the development of clay minerals for engineering applications such as nuclear waste storage and shale gas extraction.
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The poor efficacy of chimeric antigen receptor T-cell therapy (CAR T) for solid tumors is due to insufficient CAR T cell tumor infiltration, in vivo expansion, persistence, and effector function, as well as exhaustion, intrinsic target antigen heterogeneity or antigen loss of target cancer cells, and immunosuppressive tumor microenvironment (TME). Here we describe a broadly applicable nongenetic approach that simultaneously addresses the multiple challenges of CAR T as a therapy for solid tumors. The approach reprograms CAR T cells by exposing them to stressed target cancer cells which have been exposed to the cell stress inducer disulfiram (DSF) and copper (Cu)(DSF/Cu) plus ionizing irradiation (IR). The reprogrammed CAR T cells acquire early memory-like characteristics, potent cytotoxicity, enhanced in vivo expansion, persistence, and decreased exhaustion. Tumors stressed by DSF/Cu and IR also reprogram and reverse the immunosuppressive TME in humanized mice. The reprogrammed CAR T cells, derived from peripheral blood mononuclear cells of healthy donors or metastatic female breast cancer patients, induce robust, sustained memory and curative anti-solid tumor responses in multiple xenograft mouse models, establishing proof of concept for empowering CAR T by stressing tumor as a promising therapy for solid tumors.
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Neoplasias de la Mama , Receptores Quiméricos de Antígenos , Humanos , Femenino , Animales , Ratones , Leucocitos Mononucleares , Microambiente Tumoral , Neoplasias de la Mama/terapia , Modelos Animales de Enfermedad , Inmunosupresores , Linfocitos TRESUMEN
Irradiation (IR) induces immunogenic cell death (ICD) in tumors, but it rarely leads to the abscopal effect (AE). However, combining IR with immune checkpoint inhibitors has shown anecdotal success in inducing AEs. In this study, we aimed to enhance the IR-induced immune response and generate reproducible AEs using the anti-alcoholism drug disulfiram (DSF) and copper complex (DSF/Cu) via induction of tumor ICD. We measured ICD in vitro and in vivo. In mouse tumor models, DSF/Cu was injected intratumorally followed by localized tumor IR, creating an in situ cancer vaccine. We determined the anti-cancer response by primary tumor rejection and assessed systemic immune responses by tumor rechallenge and the occurrence of AEs, i.e., spontaneous lung metastasis. Additionally, we analyzed immune cell subsets and quantified proinflammatory and immunosuppressive chemokines/cytokines in the tumor microenvironment (TME) and blood of the vaccinated mice. Immune cell depletion was investigated for its effects on the vaccine-induced anti-cancer response. The results showed that DSF/Cu and IR induced more potent ICD under hypoxia than normoxia in vitro. Low-dose intratumoral injection of DSF/Cu and IR demonstrated strong anti-primary and -rechallenged tumor effects and robust AEs in mouse models. These vaccinations also increased CD8 + and CD4 + cell numbers while decreasing Tregs and myeloid-derived suppressor cells in the 4T1 model, and increased CD8+, DC, and decreased Treg cell numbers in the MCa-M3C model. Depleting both CD8 + and CD4 + cells abolished the vaccine's anticancer response. Moreover, vaccinated tumor-bearing mice exhibited increased TNFα levels and reduced levels of immunosuppressive chemokines/cytokines. In conclusion, our novel approach generated an anti-cancer immune response, resulting in a lack of or low tumor incidence post-rechallenge and robust AEs, i.e., the absence of or decreased spontaneous lung metastasis in tumor-bearing mice. This approach is readily translatable to clinical settings and may increase IR-induced AEs in cancer patients.
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In situ transcriptomic techniques promise a holistic view of tissue organization and cell-cell interactions. Recently there has been a surge of multiplexed RNA in situ techniques but their application to human tissues and clinical biopsies has been limited due to their large size, general lower tissue quality and high background autofluorescence. Here we report DART-FISH, a versatile padlock probe-based technology capable of profiling hundreds to thousands of genes in centimeter-sized human tissue sections at cellular resolution. We introduced an omni-cell type cytoplasmic stain, dubbed RiboSoma that substantially improves the segmentation of cell bodies. We developed a computational decoding-by-deconvolution workflow to extract gene spots even in the presence of optical crowding. Our enzyme-free isothermal decoding procedure allowed us to image 121 genes in a large section from the human neocortex in less than 10 hours, where we successfully recapitulated the cytoarchitecture of 20 neuronal and non-neuronal subclasses. Additionally, we demonstrated the detection of transcripts as short as 461 nucleotides, including neuropeptides and discovered new cortical layer markers. We further performed in situ mapping of 300 genes on a diseased human kidney, profiled >20 healthy and pathological cell states, and identified diseased niches enriched in transcriptionally altered epithelial cells and myofibroblasts.
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In the current work, a multiscale model was developed coupling a macro-model with the macromechanical physically based yield strength and a crystal plasticity model with micromechanical properties and realistic grain orientation based on the representative volume element. The simulation results show that the effect of microstructure on the macromechanical properties can be considered in the macro constitutive model due to a good consistency between experimental and computed results; whereas solid strengthening, grain boundaries, and dislocation density played a more crucial role than others. Besides coupling simulation and microstructure by EBSD, the microstructure evolution can be well explained by the micromechanical model. Strain is related to the grain orientation, leading to inhomogeneous deformation, forming the various Schmid factor and slip systems. A plastic strain occurs close to the grain boundaries and declines into the grain, resulting in higher kernel average misorientation (KAM) and geometry necessary dislocations (GNDs) in the grain boundaries. The higher the loading, the higher the local strain. Shear bands with around 45 degrees can be formed, resulting in crack initiation and tensile shear failure. This work has developed the guidance of structural integrity assessment and prediction of mechanical properties for the engineering material and components.
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BACKGROUND: Osthole (OST) is a bioactive natural coumarin derived from the plant Cnidium monnieri (L.) Cusson fruit (She Chuang Zi), which has various pharmacological and biological activities. OST contains an α,ß- unsaturated lactone, which is an electrophilic group that tends to be metabolized into reactive metabolites (RMs). Then, RMs are able to covalently modify nucleophilic amino acid (AA) residues of target proteins. However, few researchers considered the contribution of the covalent modification induced by OST or its metabolites. OBJECTIVE: This study aims to investigate the metabolic profile and the metabolites-protein modification of OST. METHODS: The metabolites of OST were qualitatively identified using UHPLC-Q-TOF-MS. The RMs modification patterns and potentially modified AA residues were confirmed by UHPLC-Q-TOF-MS using rat liver microsomes (RLMs) and model AAs. Finally, the modified peptides derived from high-abundance microsomal peptides were separated via nano-LC-Orbitrap-MS, and then RM-modified proteins were identified using a proteome discoverer. RESULTS: In the presence of RLMs, OST could rapidly be metabolized within 1 h and hardly identified at 4 h. We detected 10 OST metabolites, 13 OST metabolites-NAC (N-acetyl cysteine) adducts, 3 NAL (N-acetyl lysine) adducts, and 11 GSH (glutathione) adducts. Furthermore, 16 RM-modified protein targets were identified, many of which are included in the essential biological processes of OST's anti-Alzheimer's disease (AD) and anti-tumor. CONCLUSION: This study provides a novel perspective on the molecular mechanism of OST's pharmacological activities, as well as identifies potential targets for further development and application of OST and other Natural products (NPs).
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Transition metal oxides with high theoretical capacities are promising anode materials for lithium-ion batteries (LIBs). However, the sluggish reaction kinetics remain a bottleneck for fast-charging applications due to its slow Li+ migration rate. Herein, a strategy is reported of significantly reducing the Li+ diffusion barrier of amorphous vanadium oxide by constructing a specific ratio of the VO local polyhedron configuration in amorphous nanosheets. The optimized amorphous vanadium oxide nanosheets with a ratio ≈1:4 for octahedron sites (Oh ) to pyramidal sites (C4v ) revealed by Raman spectroscopy and X-ray absorption spectroscopy (XAS) demonstrate the highest rate capability (356.7 mA h g-1 at 10.0 A g-1 ) and long-term cycling life (455.6 mA h g-1 at 2.0 A g-1 over 1200 cycles). Density functional theory (DFT)calculations further verify that the local structure (Oh :C4v = 1:4) intrinsically changes the degree of orbital hybridization between V and O atoms and contributes to a higher intensity of electron occupied states near the Fermi level, thus resulting in a low Li+ diffusion barrier for favorable Li+ transport kinetics. Moreover, the amorphous vanadium oxide nanosheets possess a reversible VO vibration mode and volume expansion rate close to 0.3%, as determined through in situ Raman and in situ transmission electron microscopy.
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Trace amines (TAs) are metabolically related to catecholamine and associated with cancer and neurological disorders. Comprehensive measurement of TAs is essential for understanding pathological processes and providing proper drug intervention. However, the trace amounts and chemical instability of TAs challenge quantification. Here, diisopropyl phosphite coupled with chip two-dimensional (2D) liquid chromatography tandem triple-quadrupole mass spectrometry (LC-QQQ/MS) was developed to simultaneously determine TAs and associated metabolites. The results showed that the sensitivities of TAs increased up to 5520 times compared with those using nonderivatized LC-QQQ/MS. This sensitive method was utilized to investigate their alterations in hepatoma cells after treatment with sorafenib. The significantly altered TAs and associated metabolites suggested that phenylalanine and tyrosine metabolic pathways were related to sorafenib treatment in Hep3B cells. This sensitive method has great potential to elucidate the mechanism and diagnose diseases considering that an increasing number of physiological functions of TAs have been discovered in recent decades.
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Diosbulbin B (DIOB) has been reported to cause serious liver injury. However, in traditional medicine, DIOB-containing herbs are highly safe in combination with ferulic acid (FA)-containing herbs, suggesting potential neutralizing effect of FA on the toxicity of DIOB. DIOB can be metabolized to generate reactive metabolites (RMs), which can covalently bind to proteins and lead to hepatoxicity. In the present study, the quantitative method was firstly established for investigating the correlation between DIOB RM-protein adducts (DRPAs) and hepatotoxicity. Then, we estimated the detoxication effect of FA in combination with DIOB and revealed the underlying mechanism. Our data indicated that the content of DRPAs positively correlate with the severity of hepatotoxicity. Meanwhile, FA is able to reduce the metabolic rate of DIOB in vitro. Moreover, FA suppressed the production of DRPAs and decreased the serum alanine/aspartate aminotransferase (ALT/AST) levels elevated by DIOB in vivo. Thus, FA can ameliorate DIOB-induced liver injury through reducing the production of DRPAs.
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Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Enfermedad Hepática Inducida por Sustancias y Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Hígado/metabolismo , Proteínas/metabolismo , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/metabolismoRESUMEN
A novel amino-functionalized zinc ferrite nanoparticles/MXene (ZnFe2O4-NH2/MXene composite which consist of ZnFe2O4-NH2 and single/few layers MXene was designed and synthesized as an efficient extractant for analysis of vitamin B2 in rice first combined with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). As a result, the single/few layer MXene was tightly attached to the spherical ZnFe2O4-NH2 nanoparticles by electrostatic self-assembly interaction, which present large specific surface area and fast mass transfer rate. The relevant experimental parameters, including the pH of the solution, extraction time, adsorbent amount, desorption solvent, desorption solvent volume and desorption time were investigated and optimized. Under optimum conditions, the ZnFe2O4-NH2/MXene composite exhibited excellent selectivity and adsorption capacity for vitamin B2 through hydrogen bonding interactions and the metal-π complexation interaction. The adsorption kinetics, isotherms, and thermodynamic studies were systemically investigated to evaluate the adsorption mechanism and characteristics, which ascribed to chemical adsorption, monolayer adsorption and a spontaneous endothermic process. Furthermore, the performance of the proved method was validated with the good linear correlation coefficient (r = 0.999), low limit of detection (0.86 ng·mL-1) and the limit of quantification (2.98 ng·mL-1), satisfactory recoveries (81.7-102.5%) and reasonable accuracy (RSD<7.8%). The theoretical and technological underpinning for investigating the kinship amongst vitamin alterations and the degree of rice storage was set using this suggested approach to assess vitamin B2 in rice from various years.