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1.
Anal Chim Acta ; 1316: 342875, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969433

RESUMO

BACKGROUND: Indole-3-acetic acid (IAA) and salicylic acid (SA), pivotal regulators in plant growth, are integral to a variety of plant physiological activities. The ongoing and simultaneous monitoring of these hormones in vivo enhances our comprehension of their interactive and regulatory roles. Traditional detection methods, such as liquid chromatography-mass spectrometry, cannot obtain precise and immediate information on IAA and SA due to the complexity of sample processing. In contrast, the electrochemical detection method offers high sensitivity, rapid response times, and compactness, making it well-suited for in vivo or real-time detection applications. RESULTS: A microneedle electrochemical sensor system crafted from disposable stainless steel (SS) wire was specifically designed for the real-time assessment of IAA and SA in plant in situ. This sensor system included a SS wire (100 µm diameter) coated with carbon cement and multi-walled carbon nanotubes, a plain platinum wire (100 µm diameter), and an Ag/AgCl wire (100 µm diameter). Differential pulse voltammetry and amperometry were adopted for detecting SA and IAA within the range of 0.1-20 µM, respectively. This sensor was applied to track IAA and SA fluctuations in tomato leaves during PstDC3000 infection, offering continuous data. Observations indicated an uptick in SA levels following infection, while IAA production was suppressed. The newly developed disposable SS wire-based microneedle electrochemical sensor system is economical, suitable for mass production, and inflicts minimal damage during the monitoring of SA and IAA in plant tissues. SIGNIFICANCE: This disposable microneedle electrochemical sensor facilitates in vivo detection of IAA and SA in smaller plant tissues and allows for long-time monitoring of their concentrations, which not only propels research into the regulatory and interaction mechanisms of IAA and SA but also furnishes essential tools for advancing precision agriculture.


Assuntos
Técnicas Eletroquímicas , Ácidos Indolacéticos , Folhas de Planta , Ácido Salicílico , Solanum lycopersicum , Aço Inoxidável , Solanum lycopersicum/química , Ácidos Indolacéticos/análise , Ácido Salicílico/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Aço Inoxidável/química , Técnicas Eletroquímicas/instrumentação , Agulhas , Doenças das Plantas/microbiologia
2.
Nucleic Acids Res ; 52(9): 5107-5120, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38554113

RESUMO

Sirtuin 2 (SIRT2) regulates the maintenance of genome integrity by targeting pathways of DNA damage response and homologous recombination repair. However, whether and how SIRT2 promotes base excision repair (BER) remain to be determined. Here, we found that independent of its catalytic activity SIRT2 interacted with the critical glycosylase OGG1 to promote OGG1 recruitment to its own promoter upon oxidative stress, thereby enhancing OGG1 promoter activity and increasing BER efficiency. Further studies revealed that SIRT2 was phosphorylated on S46 and S53 by ATM/ATR upon oxidative stress, and SIRT2 phosphorylation enhanced the SIRT2-OGG1 interaction and mediated the stimulatory effect of SIRT2 on OGG1 promoter activity. We also characterized 37 cancer-derived SIRT2 mutants and found that 5 exhibited the loss of the stimulatory effects on OGG1 transcription. Together, our data reveal that SIRT2 acts as a tumor suppressor by promoting OGG1 transcription and increasing BER efficiency in an ATM/ATR-dependent manner.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , DNA Glicosilases , Reparo do DNA , Sirtuína 2 , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Humanos , Sirtuína 2/metabolismo , Sirtuína 2/genética , DNA Glicosilases/metabolismo , DNA Glicosilases/genética , Fosforilação , Regiões Promotoras Genéticas , Estresse Oxidativo , Ativação Transcricional , Células HEK293 , Dano ao DNA , Transcrição Gênica , Linhagem Celular Tumoral , Reparo por Excisão
4.
Artigo em Inglês | MEDLINE | ID: mdl-37429785

RESUMO

BACKGROUND: According to clinical practice guidelines, transarterial chemoembolization (TACE) is the standard treatment modality for patients with intermediate-stage hepatocellular carcinoma (HCC). Early prediction of treatment response can help patients choose a reasonable treatment plan. This study aimed to investigate the value of the radiomic-clinical model in predicting the efficacy of the first TACE treatment for HCC to prolong patient survival. METHODS: A total of 164 patients with HCC who underwent the first TACE from January 2017 to September 2021 were analyzed. The tumor response was assessed by modified response evaluation criteria in solid tumors (mRECIST), and the response of the first TACE to each session and its correlation with overall survival were evaluated. The radiomic signatures associated with the treatment response were identified by the least absolute shrinkage and selection operator (LASSO), and four machine learning models were built with different types of regions of interest (ROIs) (tumor and corresponding tissues) and the model with the best performance was selected. The predictive performance was assessed with receiver operating characteristic (ROC) curves and calibration curves. RESULTS: Of all the models, the random forest (RF) model with peritumor (+10 mm) radiomic signatures had the best performance [area under ROC curve (AUC) = 0.964 in the training cohort, AUC = 0.949 in the validation cohort]. The RF model was used to calculate the radiomic score (Rad-score), and the optimal cutoff value (0.34) was calculated according to the Youden's index. Patients were then divided into a high-risk group (Rad-score > 0.34) and a low-risk group (Rad-score ≤ 0.34), and a nomogram model was successfully established to predict treatment response. The predicted treatment response also allowed for significant discrimination of Kaplan-Meier curves. Multivariate Cox regression identified six independent prognostic factors for overall survival, including male [hazard ratio (HR) = 0.500, 95% confidence interval (CI): 0.260-0.962, P = 0.038], alpha-fetoprotein (HR = 1.003, 95% CI: 1.002-1.004, P < 0.001), alanine aminotransferase (HR = 1.003, 95% CI: 1.001-1.005, P = 0.025), performance status (HR = 2.400, 95% CI: 1.200-4.800, P = 0.013), the number of TACE sessions (HR = 0.870, 95% CI: 0.780-0.970, P = 0.012) and Rad-score (HR = 3.480, 95% CI: 1.416-8.552, P = 0.007). CONCLUSIONS: The radiomic signatures and clinical factors can be well-used to predict the response of HCC patients to the first TACE and may help identify the patients most likely to benefit from TACE.

5.
Aging (Albany NY) ; 15(10): 4051-4070, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37244287

RESUMO

BACKGROUND: Epigenetic regulations of immune responses are essential for cancer development and growth. As a critical step, comprehensive and rigorous explorations of m6A methylation are important to determine its prognostic significance, tumor microenvironment (TME) infiltration characteristics and underlying relationship with glioblastoma (GBM). METHODS: To evaluate m6A modification patterns in GBM, we conducted unsupervised clustering to determine the expression levels of GBM-related m6A regulatory factors and performed differential analysis to obtain m6A-related genes. Consistent clustering was used to generate m6A regulators cluster A and B. Machine learning algorithms were implemented for identifying TME features and predicting the response of GBM patients receiving immunotherapy. RESULTS: It is found that the m6A regulatory factor significantly regulates the mutation of GBM and TME. Based on Europe, America, and China data, we established m6Ascore through the m6A model. The model accurately predicted the results of 1206 GBM patients from the discovery cohort. Additionally, a high m6A score was associated with poor prognoses. Significant TME features were found among the different m6A score groups, which demonstrated positive correlations with biological functions (i.e., EMT2) and immune checkpoints. CONCLUSIONS: m6A modification was important to characterize the tumorigenesis and TME infiltration in GBM. The m6Ascore provided GBM patients with valuable and accurate prognosis and prediction of clinical response to various treatment modalities, which could be useful to guide patient treatments.


Assuntos
Glioblastoma , Humanos , Biologia Computacional , Glioblastoma/diagnóstico , Glioblastoma/terapia , Imunoterapia , Aprendizado de Máquina , Metilação , Prognóstico , Microambiente Tumoral/genética
6.
Phytomedicine ; 114: 154778, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36996529

RESUMO

BACKGROUND: Cortex Dictamni (CD) has been associated with an increased risk of liver injury, which may be attributable to the metabolic activation of its furan-containing components (FCC). However, the hepatotoxic potencies of these FCCs and the mechanisms behind the differences in their toxicity intensity remain unknown. METHODS: The constituents of CD extract were determined by LC-MS/MS. Potentially toxic FCCs were screened by a previously published method. Hepatotoxicity of potentially toxic FCCs was evaluated in cultured mouse primary hepatocytes and mice. The ability to deplete hepatic glutathione (GSH), along with the formation of the corresponding GSH conjugates, resulting from the metabolic activation was determined ex vivo in mice. Intrinsic clearance rates (CLint,Vmax/Km) were assessed by a microsome-bases assay. RESULTS: A total of 18 FCCs were detected in CD extract. Among them, four FCCs, including rutaevin (RUT), limonin (LIM), obacunone (OBA) and fraxinellone (FRA) were found to be bioactivated in microsomal incubations. Only FRA displayed significant hepatotoxicity in vitro and in vivo. Similarly, FRA caused GSH depletion and GSH conjugation the most in vivo. The order of CLint for the four FCCs was FRA>>OBA>LIM>RUT. CONCLUSION: FRA is the major toxic FCC component of hepatotoxic CD extract. The hepatotoxicity of FCCs is closely related to the efficiency of their metabolic activation.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Espectrometria de Massas em Tandem , Camundongos , Animais , Ativação Metabólica , Cromatografia Líquida , Furanos , Extratos Vegetais , Glutationa/metabolismo
7.
Toxicol Lett ; 379: 20-34, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36905973

RESUMO

Columbin (CLB) is the most abundant (>1.0%) furan-containing diterpenoid lactone in herbal medicine Tinospora sagittate (Oliv.) Gagnep. The furano-terpenoid was found to be hepatotoxic, but the exact mechanisms remain unknown. The present study demonstrated that administration of CLB at 50 mg/kg induced hepatotoxicity, DNA damage and up-regulation of PARP-1 in vivo. Exposure to CLB (10 µM) induced GSH depletion, over-production of ROS, DNA damage, up-regulation of PARP-1 and cell death in cultured mouse primary hepatocytes in vitro. Co-treatment of mouse primary hepatocytes with ketoconazole (10 µM) or glutathione ethyl ester (200 µM) attenuated the GSH depletion, over-production of ROS, DNA damage, up-regulation of PARP-1, and cell death induced by CLB, while co-exposure to L-buthionine sulfoximine (BSO, 1000 µM) intensified such adverse effects resulting from CLB exposure. These results suggest that the metabolic activation of CLB by CYP3A resulted in the depletion of GSH and increase of ROS formation. The resultant over-production of ROS subsequently disrupted the DNA integrity and up-regulated the expression of PARP-1 in response to DNA damage, and ROS-induced DNA damage was involved in the hepatotoxicity of CLB.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Diterpenos , Animais , Camundongos , Butionina Sulfoximina/farmacologia , Dano ao DNA , Glutationa/metabolismo , Lactonas , Inibidores de Poli(ADP-Ribose) Polimerases/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
8.
Food Chem Toxicol ; 174: 113688, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36841326

RESUMO

Safrole (SFL) is an IARC class 2B carcinogen. To better understand the mechanism involved in SFL toxicity, we explored the potential interactions between SFL metabolites and RNA. Three guanosine adducts (G1-G3), two adenosine adducts (A1-A2), and two cytosine adducts (C1-C2) were detected by LC-MS/MS in mouse liver S9 incubations, cultured mouse primary hepatocytes, and liver tissues of mice after exposure to SFL. These adducts were chemically synthesized, and one of the guanosine adducts was structurally characterized by 1H-NMR. Studies in vitro and in vivo showed that SFL was oxidized by cytochrome P450 enzymes to the corresponding 1'-hydroxyl metabolite which was further metabolized by sulfotransferases to form allylic sulfate esters. The formed reactive intermediate(s) subsequently reacted with bases of RNA, leading to RNA adduction, which could play a partial role in the toxicities of SFL through the alteration of RNA biochemical properties and interruption of RNA functions.


Assuntos
Safrol , Sulfotransferases , Camundongos , Animais , Ativação Metabólica , Cromatografia Líquida , Sulfotransferases/metabolismo , RNA/metabolismo , Especiarias , Espectrometria de Massas em Tandem , Sistema Enzimático do Citocromo P-450/metabolismo , Adutos de DNA
9.
ACS Sens ; 8(1): 263-269, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36624088

RESUMO

Developing a self-checking photoelectrochemical biosensor with dual photocurrent signals could efficiently eliminate false-positive or false-negative signals. Herein, a novel biosensor with dual photocurrent responses was established for the detection of acetylcholinesterase activity. To achieve photocurrent polarity-switchable behavior, the iodide/tri-iodide redox couple was innovatively introduced to simultaneously consume the photoexcited electrons and holes, which circumvents the inconvenience caused by the addition of different hole- and electron-trapping agents in the electrolyte. Importantly, benefiting from the high catalytic activity, the enhanced photoelectric responsivity can be realized after decorating the counter electrode with nickel single-atom catalysts, which promotes a more efficient iodide/tri-iodide redox reaction under low applied voltages. It is envisioned that the proposed photocurrent polarity switching system offers new routes to sensitive and reliable biosensing.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Acetilcolinesterase , Iodetos , Níquel , Oxirredução , Catálise
10.
Oncogene ; 42(8): 586-600, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36550358

RESUMO

The MRE11-RAD50-NBS1 (MRN) complex plays a crucial role in DNA double-strand breaks (DSBs) sensing and initiation of signaling cascades. However, the precise mechanisms by which the recruitment of MRN complex is regulated has yet to be elucidated. Here, we identified TRIpartite motif-containing protein 24 (TRIM24), a protein considered as an oncogene overexpressed in cancers, as a novel signaling molecule in response to DSBs. TRIM24 is essential for DSBs-induced recruitment of MRN complex and activation of downstream signaling. In the absence of TRIM24, MRN mediated DSBs repair is remarkably diminished. Mechanistically, TRIM24 is phosphorylated by ataxia-telangiectasia mutated (ATM) and then recruited to DSBs sites, facilitating the accumulation of the MRN components to chromatin. Depletion of TRIM24 sensitizes human hepatocellular carcinoma cells to cancer therapy agent-induced apoptosis and retards the tumor growth in a subcutaneous xenograft tumor mouse model. Together, our data reveal a novel function of TRIM24 in response to DSBs through regulating the MRN complex, which suggests that TRIM24 may be a potential therapeutic molecular target for tumor treatment.


Assuntos
Proteínas de Transporte , Proteínas de Ciclo Celular , Quebras de DNA de Cadeia Dupla , Animais , Humanos , Camundongos , Hidrolases Anidrido Ácido/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Reparo do DNA , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Proteína Homóloga a MRE11/genética , Proteína Homóloga a MRE11/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo
11.
J Orthop Res ; 41(6): 1335-1347, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36370141

RESUMO

Macrophage infiltration and polarization during lumbar intervertebral disc herniation (LDH) have attracted increased attention but their role remains unclear. To explore macrophage polarization in herniated nucleus pulposus (NP) tissue of patients with LDH and investigate the association between cell frequency and different clinical characteristics or symptoms, we conducted a retrospective study by analyzing NP tissue samples from 79 patients. Clinical features and symptoms, using the visual analog scale (VAS) and Oswestry disability index (ODI), were collected. The macrophage markers CD68, CCR7, CD163, and CD206; pro-inflammatory cytokine TNF-α; and anti-inflammatory factor IL-4 were analyzed by immunohistochemistry. The frequency of polarized macrophages and positivity rate of pro- and anti-inflammatory cytokines showed significant differences in some of clinical characteristics. Specifically, higher CCR7+ and TNF-α + proportions were identified in the high-intensity zone (HIZ) and the type of extrusion and sequestration NP tissue than in non-HIZ and protrude NP tissue. Higher CD206+ and IL-4+ proportion were detected in Modic changes. However, no differences in gender, age, smoking status, Pfirrmann grade, analgesic use, leg pain duration, and segments were found between groups. CD68+ , CCR7+ , and CD206+ cell proportions, and TNF-α and IL-4 showed positive associations with VAS scores preoperation. Associations between ODI and the macrophages markers were weak/insignificant. Our results indicated that macrophage polarization or macrophage-like cells contribute to LDH pathological features. Macrophage populations displaying significant associations with VAS score reflected continuous M1/M2 transition contributing to pain during LDH. These findings may contribute to enhanced/personalized pharmacological interventions for patients with LDH considering pain heterogeneity.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Humanos , Deslocamento do Disco Intervertebral/patologia , Estudos Retrospectivos , Núcleo Pulposo/patologia , Interleucina-4/metabolismo , Receptores CCR7/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Dor , Vértebras Lombares/cirurgia , Macrófagos/metabolismo , Degeneração do Disco Intervertebral/patologia , Disco Intervertebral/patologia
12.
Cancers (Basel) ; 14(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36428700

RESUMO

Chromosomal instability (CIN) covers approximately 65 to 70% of colorectal cancer patients and plays an essential role in cancer progression. However, the molecular features and therapeutic strategies related to those patients are still controversial. R-loop binding proteins (RLBPs) exert significant roles in transcription and replication. Here, integrative colorectal cancer proteogenomic analysis identified two RLBPs subtypes correlated with distinct prognoses. Cluster I (CI), represented by high expression of RLBPs, was associated with the CIN phenotype. While Cluster II (CII) with the worst prognosis and low expression of RLBPs was composed of a high percentage of patients with mucinous adenocarcinoma or right-sided colon cancer. The molecular feature analysis revealed that the active RNA processing, ribosome synthesis, and aberrant DNA damage repair were shown in CI, a high inflammatory signaling pathway, and lymphocyte infiltration was enriched in CII. In addition, we revealed 42 tumor-associated RLBPs proteins. The CI with high expression of tumor-associated proteins was sensitive to drugs targeting genome integrity and EGFR in both cell and organoid models. Thus, our study unveils a significant molecular association of the CIN phenotype with RLBPs, and also provides a powerful resource for further functional exploration of RLBPs in cancer progression and therapeutic application.

13.
Int J Hyperthermia ; 39(1): 1294-1299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36191925

RESUMO

PURPOSE: To compare the efficacy and safety of focused ultrasound (FUS) therapy and cryotherapy for cervical squamous intraepithelial lesion (SIL). METHODS: In this retrospective study, data pertaining to women treated for cervical SIL with FUS therapy or cryotherapy at the Second Affiliated Hospital of Chongqing Medical University between 21 April 2018 and 31 August 2020 were obtained. The patients were followed up after 3-6 and 6-12 months. The proportions of women with no evidence of disease, recurrent disease, clearance of the human papillomavirus (HPV) and adverse effects or complications were determined. RESULTS: Of the 250 women with complete data who were included in the study, 144 and 106 received FUS therapy and cryotherapy, respectively. Overall, FUS therapy was observed to be more effective than cryotherapy (91.7 vs. 79.2%, p = 0.005). Statistically significant differences were noted in the treatment efficacy for patients with low-grade SIL (LSIL) (92.3 vs. 80.2%, p = 0.011). However, there were no significant differences in the treatment efficacy for patients with high-grade SIL (HSIL) (88.9 vs. 75.0%, p = 0.390). The recurrence rates in patients with LSIL treated with FUS therapy or cryotherapy showed no significant differences at the 6-12-month follow-up (1.0 vs. 6.0%, p = 0.163). Furthermore, there was no recurrence in patients with HSIL, either in the FUS or cryotherapy group. FUS therapy and cryotherapy resulted in similar HPV clearance at the 3-6-month follow-up (77.1 vs. 64.8%, p = 0.057). No statistically significant differences were observed in the complication rates between the two groups (3.5 vs. 1.9%, p = 0.717). CONCLUSION: The results of this study suggest that FUS therapy is superior to cryotherapy in the treatment of cervical LSIL.


Assuntos
Infecções por Papillomavirus , Lesões Intraepiteliais Escamosas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Crioterapia , Feminino , Humanos , Papillomaviridae , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/terapia , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Displasia do Colo do Útero/diagnóstico por imagem , Displasia do Colo do Útero/terapia
14.
Front Immunol ; 13: 922173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059551

RESUMO

Macrophage infiltration and polarization have been increasingly observed in intervertebral disc (IVD) degeneration (IDD). However, their biological roles in IDD are still unrevealed. We harvested conditioned media (CM) derived from a spectrum of macrophages induced from THP-1 cells, and examined how they affect nucleus pulposus cells (NPCs) in vitro, by studying cell proliferation, extracellular matrix (ECM) synthesis, and pro-inflammation expression; and in vivo by injection CM in a rat IDD model. Then, high-throughput sequencing was used to detect differentially expressed genes (DEGs). Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) networks were used to further analysis. Higher CCR7+ (M1 marker) and CD206+ (M2 marker) cell counts were found in the degenerated human IVD tissues as compared with the control. Furthermore, the cell co-culture model showed M1CM attenuated NPC proliferation, downregulated the expression of ECM anabolic genes encoding aggrecan and collagen IIα1, upregulated the expression of ECM catabolic genes encoding MMP-13, and inflammation-related genes encoding IL-1ß, IL-6, and IL-12, while M2CM showed contrasting trends. In IDD model, higher histological scores and lower disc height index were found following M1CM treatment, while M2CM exhibited opposite results. M1CM injection decreased ECM anabolic and increased ECM catabolic, as well as the upregulation of inflammation-related genes after 8 weeks treatment, while M2CM slowed down these trends. Finally, a total of 637 upregulated and 655 downregulated genes were detected in M1CM treated NPCs, and 975 upregulated genes and 930 downregulated genes in the M2CM groups. The top 30 GO terms were shown and the most significant KEGG pathway was cell cycle in both groups. Based on the PPI analysis, the five most significant hub genes were PLK1, KIF20A, RRM2, CDC20, and UBE2C in the M1CM groups and RRM2, CCNB1, CDC20, PLK1, and UBE2C in the M2CM groups. In conclusion, macrophage polarization exhibited diverse roles in IDD progression, with M1CM exacerbating cell proliferation suppression and IVD degeneration, while M2CM attenuated IDD development. These findings may facilitate the further elucidation of the role of macrophage polarization in IDD, and provide novel insights into the therapeutic potential of macrophages.


Assuntos
Degeneração do Disco Intervertebral , Animais , Proliferação de Células , Matriz Extracelular/metabolismo , Humanos , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Macrófagos/metabolismo , Ratos
15.
Chem Biol Interact ; 365: 110047, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35917946

RESUMO

Pyrrolizidine alkaloids (PAs) are among the most significant hepatotoxins widely distributed in plant species. Incidence of liver injuries caused by PAs has been reported worldwide, and the reactive metabolites of PAs are known to play a critical role in causing the hepatotoxicity. To better understand the toxicity-induction mechanisms, we explored the interactions of PA metabolites with cellular RNA molecules, and examined their effects on the biochemical and metabolic properties of hepatic RNAs. After exposure to retrorsine, adduction on adenosine and guanosine were detected in mouse liver microsomal incubations, cultured mouse primary hepatocytes, and mouse liver tissues. NMR analysis showed that the exocyclic amino group participated in the adduction. We found drastically altered properties and metabolism of the adducted RNA such as reverse-transcriptability, translatability, and RNase-susceptibility. In addition, endogenous modification of N6-methyladenosine (m6A) was remarkably reduced.


Assuntos
Alcaloides de Pirrolizidina , RNA , Ativação Metabólica , Animais , Fígado , Camundongos , Microssomos Hepáticos/metabolismo , Alcaloides de Pirrolizidina/metabolismo , Alcaloides de Pirrolizidina/toxicidade , RNA/metabolismo
16.
Phytomedicine ; 102: 154174, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35660353

RESUMO

BACKGROUND: Dioscorea bulbifera L. (DBL) is an herbal medicine used for the treatment of thyroid diseases and tumors in China. However, the hepatotoxicity of DBL limits its wide safe use. Diosbulbin B (DSB) is the most abundant diterpene lactone occurring in DBL. Numbers of studies showed that this furanoterpenoid plays an important role in DBL-induced liver injury and that DSB is metabolized to a cis-enedial intermediate which reacts with protein to form protein covalent binding and induces hepatotoxicity. PURPOSE: The present study aimed to define the association of DSB content in DBL with the severity of DBL hepatotoxicity to ensure the safe use of the herbal medicine in clinical practice and to determine the role of DSB in DBL-induced liver injury. METHODS: Chemical chromatographic fingerprints of DBL were established by UPLC-MS/MS. Their hepatotoxicity potencies were evaluated in vitro and in vivo. Metabolic activation of DSB was evaluated by liver microsomal incubation. Protein modification was assessed by mass spectrometry and immunostaining. RESULTS: The contents of DSB in DBL herbs collected from 11 locations in China varied dramatically with as much as 47-fold difference. The hepatotoxicity potencies of DBL herbs were found to be proportional to the contents of DSB. Intensified protein adduction derived from the reactive metabolite of DSB was observed in mice administered DBL with high contents of DSB. CONCLUSION: The findings not only demonstrated that contents of DSB can be quite different depending on harvest location and special attention needs to pay for quality control of DBL but also suggest DSB is a key contributor for DBL-induced hepatotoxicity.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Dioscorea , Plantas Medicinais , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Cromatografia Líquida , Dioscorea/química , Compostos Heterocíclicos de 4 ou mais Anéis , Camundongos , Espectrometria de Massas em Tandem
18.
Xenobiotica ; 52(4): 360-369, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35575452

RESUMO

2-Methylnaphthalene (2-MN) is an environmental pollutant. Studies have shown that 2-MN is teratogenic, carcinogenic, and cytotoxic. However, the mechanisms of 2-MN induced toxicities remain unclear.This study aimed to characterise reactive metabolites of 2-MN, to define the metabolic pathway, and to determine the enzymes participating in the metabolic activation.A hydroxylation metabolite of 2-MN, 2-naphthalenemethanol (2-NM), was observed in 2-MN-containing mouse liver microsomes.A glutathione (GSH) conjugate was detected in mouse S9 incubations fortified with 2-MN and GSH. A GSH conjugate and an NAC conjugate were found in mouse liver and urine, respectively, in animals given 2-MN. Hepatic protein covalent binding derived from 2-NM was observed in animals administered 2-MN.Cytochrome P450 enzymes and sulfotransferases participated in the metabolic activation of 2-MN.


Assuntos
Microssomos Hepáticos , Naftalenos , Ativação Metabólica , Animais , Glutationa/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Naftalenos/metabolismo
19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(2): 238-243, 2022 Feb 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-35545414

RESUMO

OBJECTIVES: Accurate breast lesion surface localization can guarantee accurate biopsy and local treatment. But there is no guideline to regular equipment and methods for the localization of breast lesions. The conventional non-invasive localization method is marker-based localization. The advantages of this method are simple and efficient. The disadvantages are that markers disappear easily under coupling agents; the positioning length of markers cannot last long on skin; and healthcare associated infection due to many patients using the same marker pen is potentially unavoidable. Breast lesion sticker (called sticker for short) is a new-type localization medical instrument in 2020. Our study aims to explore the clinical value of a new lesion stickers in breast lesion surface localization via comparison of the sticker and marker pen localization methods. METHODS: This was a prospective cohort study. It was conducted in 67 patients who needed breast lesion surface localization before biopsy. The patients were randomly assigned into 2 groups. One group of patients used marker pen to mark breast lesion surface location by ultrasonography. The other group of patients used stickers. Patients labeled with markers on skin were swabbed agents before marking. Then the markers were checked by ultrasound scan. If the surface positions of breast lesion were not correct, the above procedure was repeated. In the sticker group, the stickers were released synchronously after the lesions were detected by ultrasound scan. Then locations were checked via scanning hole. If the surface positions of breast lesion were not correct, the above procedure was repeated. The accuracy of positioning, the length of positioning time and satisfaction of patients between the 2 groups were compared. The length of positioning time was calculated from the time when ultrasound detected the lesion to the time when the surface position of breast lesion was confirmed. The total score of patients' satisfaction was 5 points according to Service Quality Evaluation of SERVQUAL Scale, including sonographers' service attitude and their technical proficiency, other medical staffs' service attitude and their technical proficiency, hospital service procedures, positioning comfort, and positioning effects. RESULTS: All 67 patients were females, aged 18-66 (39.73±13.10). There were 35 patients in the marker pen group and 32 patients in the sticker group. The time length of group used marker pen to localization was 22-88 (52.20±2.90) s, and the sticker group was 3-15 (9.22±0.58) s in length. The length of positioning time for the stickers was significantly shorter than that of the marker (P<0.01). Both methods were accurate in the surface localization of lesions before operation. The total scores of patients' satisfaction was 4-5 (4.92±0.02) in the stickers group, and 1-5 (3.35±0.10) in the marker pen group. The patients' satisfaction scores with the sticker were significantly higher than those with the marker pen (P<0.01). The length of positioning time and patients' satisfication scores for sonographer with 20 years' working experience were shorter and higher than those of sonographer with 10 years' working experience, respectively (both P<0.05). CONCLUSIONS: The new breast lesion positioning stickers have more advantages than the marker pen in localization efficiency. It could reduce the workload of medical workers and increase patients' satisfaction to some extent. The stickers can be used not only in the breast lesions surface localization, but also in the skin location of pleural effusion and ascites, the skin location of surface masses, the skin location of thyroid nodule, and many other clinical marker areas, to further expand the scope of clinical application and value of the stickers.


Assuntos
Neoplasias da Mama , Mama , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Masculino , Estudos Prospectivos , Pele
20.
Chem Res Toxicol ; 35(5): 817-828, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35476398

RESUMO

Bletilla striata is consumed as food and herbal medicine. Militarine (MLT) is a major ingredient in B. striata. Previous studies demonstrated that MLT showed teratogenic toxicity to zebrafish embryos. The present study aimed to identify reactive metabolites possibly involved in the cytotoxicity of MLT and determine the metabolic pathways involved. MLT was found to be hydrolyzed to p-hydroxybenzyl alcohol (HBA) by ß-glucosidase and esterases. The resulting HBA further underwent spontaneous dehydration to form quinone methide. HBA was also metabolized to the corresponding sulfate, followed by departure of the sulfate to generate a quinone methide. The resultant quinone methide reacted with hepatic glutathione (GSH) and protein to form the corresponding GSH conjugate and protein adduction. Additionally, inhibition of sulfotransferases (SULTs) attenuated the susceptibility of hepatocytes to the toxicity of MLT. This study provides that the hydrolytic enzymes ß-glucosidase, esterases, and SULTs participate in the metabolic activation of MLT.


Assuntos
Celulases , Peixe-Zebra , Ativação Metabólica , Animais , Celulases/metabolismo , Esterases/metabolismo , Glutationa/metabolismo , Succinatos , Sulfatos , Sulfotransferases/metabolismo , Peixe-Zebra/metabolismo
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