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Abnormal activation of the Wnt/ß-catenin signaling pathway is a driving force behind the progression of gastric cancer. Atovaquone, known as an antimalarial drug, has emerged as a potential candidate for anti-cancer therapy. This study investigated atovaquone's effects on gastric cancer and its underlying mechanisms. Using gastric cancer cell lines, we found that atovaquone, at concentrations relevant to clinical use, significantly reduced their viability. Notably, atovaquone exhibited a lower effectiveness in reducing the viability of normal gastric cells compared to gastric cancer cells. We further demonstrated that atovaquone inhibited gastric cancer growth and colony formation. Mechanism studies revealed that atovaquone inhibited mitochondrial respiration and induced oxidative stress. Experiments using ρ0 cells, deficient in mitochondrial respiration, indicated a slightly weaker effect of atovaquone on inducing apoptosis compared to wildtype cells. Atovaquone increased phosphorylated ß-catenin at Ser45 and Ser33/37/Thr41, elevated Axin, and reduced ß-catenin. The inhibitory effects of atovaquone on ß-catenin were reversed upon depletion of CK1α. Furthermore, the combination of atovaquone with paclitaxel suppressed gastric cancer growth and improved overall survival in mice. Given that atovaquone is already approved for clinical use, these findings suggest its potential as a valuable addition to the drug arsenal available for treating gastric cancer.
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Neoplasias Gástricas , Via de Sinalização Wnt , Animais , Camundongos , Atovaquona/farmacologia , Atovaquona/uso terapêutico , beta Catenina/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Linhagem Celular Tumoral , Caseína Quinases/metabolismo , Proliferação de CélulasRESUMO
This study utilizes mechanochemistry to prepare retinol acetate (RA) solid dispersion (RA-sodium starch octenyl succinate (SSOS)), resulting in improved solubility, stability, and bioavailability compared with raw RA and commercial RA microcapsules. RA, poloxamer 188, SSOS, and milling beads (8 mm) were mixed in a ratio of 2:1:8:220 (w/w) and ball-milled at 100 rpm for 3 h. RA-SSOS exhibited a solubility of 1020.35 µL/mL and a 98.09% retention rate after aging at 30 °C. Rats fed with RA-SSOS showed an â¼30% increase in organ RA content. Characterization analysis attributed the solubility and stabilization of RA-SSOS to hydrogen bonding between RA and SSOS, along with an amorphous state. RA-SSOS offers significant advantages for the pharmaceutical and food industries, leveraging mechanochemistry to enhance solid dispersions for hydrophobic compounds and optimize drug delivery.
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Disponibilidade Biológica , Ésteres de Retinil , Solubilidade , Vitamina A , Animais , Ratos , Vitamina A/química , Vitamina A/farmacocinética , Ésteres de Retinil/química , Masculino , Ratos Sprague-Dawley , Estabilidade de Medicamentos , Amido/química , DiterpenosRESUMO
BACKGROUND: Despite emerging evidence linking blood cell indices (BCIs) to sepsis mortality, the inconsistency of observational studies obscures the clarity of these associations. This study aims to clarify the causal influence of BCIs on 28-day mortality rates in sepsis patients. METHODS: Utilizing univariable and multivariable Mendelian randomization (MR) analyses, we examined the impact of BCIs on sepsis mortality by analyzing data from extensive genome-wide association studies. The inverse-variance weighted (IVW) method was our primary analytic tool, complemented by several robustness checks to mitigate pleiotropy, including weighted median, mode-based estimates, MR-Egger regression, and MR-PRESSO. Subsequently, we conducted a retrospective study to further explore the correlation between platelet indices and 28-day mortality of sepsis using real-world data. RESULTS: Our findings highlight a significant causal relationship between platelet distribution width (PDW) and 28-day mortality in sepsis, with the univariable Mendelian randomization approach yielding an odds ratio of 1.12 (95% CI, 1.06-1.26; P < 0.05). Multivariable analysis further substantiated PDW's robust association with mortality risk (OR 1.23; 95% CI, 1.03-1.48; P < 0.05). Conversely, our analysis did not uncover significant correlations between the genetic predispositions to other BCIs-including red blood cell count, erythrocyte distribution width, platelet count, mean platelet volume, white blood cell count, neutrophil count, neutrophil percentage, lymphocyte count, and lymphocyte percentage-and 28-day mortality in sepsis. Additionally, an inverse MR analysis did not establish a causal impact of 28-day mortality in sepsis on PDW (OR 1.00; 95% CI, 1.00-1.07; P = 0.29). Moreover, a similar result was observed in the retrospective study. CONCLUSIONS: The study underscores the independent causal role of PDW in predicting 28-day mortality in sepsis, suggesting its potential utility in early patient assessment, risk stratification, and tailoring of therapeutic interventions.
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Análise da Randomização Mendeliana , Sepse , Humanos , Sepse/mortalidade , Sepse/sangue , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Estudo de Associação Genômica Ampla , Idoso , PlaquetasRESUMO
BACKGROUND: Focal liver lesions (FLLs) are a common form of liver disease, and identifying accurate pathological types is required to guide treatment and evaluate prognosis. PURPOSE: To compare and analyze the application effect of contrast-enhanced ultrasound (CEUS) and conventional ultrasound (US) in the clinical diagnosis of focal liver lesions. MATERIAL AND METHODS: A retrospective analysis was performed on 682 patients with space-occupying liver lesions admitted to our hospital between December 2015 and August 2021. Of these, 280 underwent CEUS-guided biopsies and 402 underwent conventional US biopsies, with the results of each biopsy subsequently compared between the two groups. The success rate and accuracy of the biopsies and their relationship with different pathological features were also analyzed. RESULTS: The success rate, sensitivity, diagnostic accuracy, positive predictive value, and negative predictive value of the CEUS group were significantly higher than those of the US group (P < 0.05). Lesion size accuracy in the CEUS group was significantly higher than that in the US group (89.29% vs. 40.55%; P < 0.05). Lesion type accuracy in the CEUS group was significantly higher than that in the US group (86.49% vs. 43.59%), and the difference between the two groups was statistically significant (P < 0.05). The logistic regression analysis indicated that malignant lesions, lesions ≥5 cm, and lesions ≤1 cm were independent factors affecting the success rate of the puncture procedure (P < 0.05). CONCLUSION: The sensitivity, specificity, and diagnostic accuracy of lesion size and type in the CEUS group were higher than those in the US group.
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Meios de Contraste , Sensibilidade e Especificidade , Ultrassonografia , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia/métodos , Adulto , Idoso , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Hepatopatias/diagnóstico por imagem , Hepatopatias/patologia , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Valor Preditivo dos Testes , Adulto JovemRESUMO
Keeping railway tracks in good operational condition is one of the most important tasks for railway owners. As a result, railway companies have to conduct track inspections periodically, which is costly and time-consuming. Due to the rapid development in computer science, many prediction models using machine learning methods have been developed. It is possible to discover the degradation pattern and develop accurate prediction models. The paper reviews the existing prediction methods for railway track degradation, including traditional methods and prediction methods based on machine learning methods, including probabilistic methods, Artificial Neural Network (ANN), Support Vector Machine (SVM), and Grey Model (GM). The advantages, shortage, and applicability of methods are discussed, and recommendations for further research are provided.
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Aprendizado de Máquina , Redes Neurais de Computação , Máquina de Vetores de SuporteRESUMO
As a promising therapy, photothermal therapy (PTT) converts near-infrared (NIR) light into heat through efficient photothermal agents (PTAs), causing a rapid increase in local temperature. Considering the importance of PTAs in the clinical application of PTT, the safety of PTAs should be carefully evaluated before their widespread use. As a promising PTA, mesoporous polydopamine (MPDA) was studied for its clinical applications for tumor photothermal therapy and drug delivery. Given the important role that intestinal microflora plays in health, the impacts of MPDA on the intestine and on intestinal microflora were systematically evaluated in this study. Through biological and animal experiments, it was found that MPDA exhibited excellent biocompatibility, in vitro and in vivo. Moreover, 16S rRNA analysis demonstrated that there was no obvious difference in the composition and classification of intestinal microflora between different drug delivery groups and the control group. The results provided new evidence that MPDA was safe to use in large doses via different drug delivery means, and this lays the foundation for further clinical applications.
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Microbioma Gastrointestinal , Hipertermia Induzida , Nanopartículas , Animais , Compostos de Diazônio , Indóis , Intestinos , Fototerapia , Polímeros , Piridinas , RNA Ribossômico 16S/genéticaRESUMO
In this Letter, we propose a compact fiber tilt sensor based on a microbubble suspended in a liquid-filled microcavity at the end of a single-mode fiber. By coupling a single-frequency laser with enough power, the microbubble could suspend in the microcavity due to the Marangoni effect, which constitutes a Fabry-Perot interferometer. When the tilt angle changes, the position of the microbubble changes as well, which causes the variation of the dominant frequency of the interference fringes in the spectrum. The experimental results show that the tilt angle sensitivity of the sensor reaches ${3.64} \times {{10}^{ - 4}}\;{{\rm nm}^{ - 1}}/{\rm Deg}$3.64×10-4nm-1/Deg at a wide sensing range from ${-}{45}^\circ $-45∘ to 45° with a good repeatability.
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A simple fiber-optic sensor for simultaneous measurement of high pressure and high temperature was proposed. The sensor was simply fabricated by splicing two sections of silica capillary tubes (SCTs) with different inner diameters to the single-mode fiber. The thick core SCT functions as a Fabry-Perot (FP) micro-cavity and an anti-resonant reflecting waveguide at the same time. The two different sensing mechanisms lead to the high contrast sensitivity values of pressure and temperature (â3.76 nm/MPa, 27.7 pm/°C and 4.24 nm/MPa, 0.82 pm/°C). We also proposed a simple and effective method to evaluate the actual sensitivities of two-parameter sensors by using linear programming, which shows that our sensor is more sensitive than others in high pressure and high temperature simultaneous detection. Besides, low cost, good mechanical property and convenient reflective probe make the sensor more competitive in actual application.
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Background: Anti-EGFR mAb are recommended treatment for metastatic colorectal cancer (mCRC). Accurate mutation profiling and disease monitoring are challenging. The current study investigates the potential use of transrenal DNA as a biomarker for disease management. Methods: Agreement between archival tissue specimens and transrenal DNA extracted from 200 post-treated mCRC patients was determined. Total DNA concentrations were measured and mutations within the KRAS and EGFR genes were profiled for each specimen. To ascertain therapy resistance; patients were serially monitored monthly. Results: Concordance measurement with matched tissues at baseline was remarkably high (92%) for EGFR and KRAS mutations. Sensitivity and specificity were 98.4% and 89.1% respectively. Newly detectable mutations for a subgroup of patients with initial wildtype characteristics were evident after 4 months of anti-EGFR mAb therapy. Survival analysis using adjusted estimates showed that patients detected by transrenal DNA for key mutations or had higher mutant DNA content had poorer outcome. Conclusion: Transrenal DNA offers new options to follow clinical treatment in mCRC. It demonstrates the ability to capture newly acquired mutations that has strong associative links to therapy resistance. Patients with these mutations fared poorly for survival outcomes and indicated possible prognostic value for transrenal DNA detection.
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Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/genética , Biomarcadores Tumorais/imunologia , Cetuximab/uso terapêutico , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/imunologia , Feminino , Expressão Gênica , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Mutação , Panitumumabe/uso terapêutico , Prognóstico , Proteínas Proto-Oncogênicas p21(ras)/imunologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Análise de SobrevidaRESUMO
Mitochondria has been identified as a promising target in several cancers. However, little is known on the effects of targeting mitochondria in retinoblastoma. In this work, we show that anti-malarial atovaquone, at clinically achievable concentration, demonstrates inhibitory effects to retinoblastoma cells, to a more extent than in normal retinal cells. Atovaquone also significantly increases chemosensitivity in retinoblastoma. Importantly, we show that retinoblastoma cells have higher level of mitochondrial respiration, membrane potential, mass and ATP compared to normal retinal cells. Although atovaquone significantly inhibits mitochondrial respiration and decrease ATP level in both malignant and normal retinal cells in a similar manner, atovaquone induces much more oxidative stress and damage in retinoblastoma than normal retinal cells. These suggest that normal retinal cells are more tolerable to mitochondrial dysfunctions than retinoblastoma cells. We further demonstrate that atovaquone targets Akt/AMPK/mTOR signaling via inducing mitochondrial dysfunction. Our pre-clinical work demonstrates the translational potential of atovaquone as an addition to the treatment armamentarium for retinoblastoma. Our work also demonstrates the differences of mitochondrial biogenesis and function in malignant versus normal retinal cells which are important for the targeted therapy in retinoblastoma.
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Antineoplásicos/farmacologia , Atovaquona/farmacologia , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Retinoblastoma/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Antimaláricos/farmacologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Dano ao DNA , Glicólise , Humanos , Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Retina/metabolismo , Retinoblastoma/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
Joint stiffness and fibrosis are common complications that affect mobility and quality of life, necessitating effective therapeutic strategies to alleviate these issues. The study aimed to observe the therapeutic effect of static progressive stretching (SPS) combined with botulinum toxin type A (BTX-A) on knee joint stiffness in rats and its effect on the transforming growth factor beta 1 (TGF-ß1)/small mother against decapentaplegic (Smad) pathway in the development of joint capsule fibrosis. Forty Sprague Dawley rats were randomly divided into the blank control group, model control group, SPS intervention group, BTX-A intervention group, and SPS combined with BTX-A intervention group. Except for the blank control group, the right knee joints of the other rats were surgically fixed with Kirschner wire internal immobilization in full flexion for four weeks to form joint flexion contracture and cause fibrotic stiffness of the joint. The therapeutic effect of each intervention was assessed by the range of motion (ROM) of the knee joint, joint stiffness, the number of total cells, and collagen deposition in the posterior joint capsule, as well as the protein level expressions of TGF-ß1, Smad2, Smad3, Smad4, p-Smad2/3, collagen I and III, and alpha smooth muscle actin (α-SMA) in the posterior joint capsule in the TGF-ß1/Smad pathway. SPS combined with BTX-A was more effective in relieving joint fibrosis stiffness, improving the histopathological changes in the posterior joint capsule, and suppressing the high expression of target proteins and the overactivated TGF-ß1/Smad pathway. The overactivated TGF-ß1/Smad pathway was involved in the formation of knee joint fibrosis stiffness in rats. SPS combined with BTX-A was effective in relieving joint flexion contracture and fibrosis of the joint capsule. Moreover, the inhibition of the overactivated TGF-ß1/Smad pathway may be the potential molecular mechanism for its therapeutic effect.
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The pseudokinase mixed lineage kinase domain-like (MLKL) is an essential component of the activation of the necroptotic pathway. Emerging evidence suggests that MLKL plays a key role in liver disease. However, how MLKL contributes to hepatocarcinogenesis has not been fully elucidated. Herein, we report that MLKL is upregulated in a diethylnitrosamine (DEN)-induced murine HCC model and is associated with human hepatocellular carcinomas. Hepatocyte-specific MLKL knockout suppresses the progression of hepatocarcinogenesis. Conversely, MLKL overexpression aggravates the initiation and progression of DEN-induced HCC. Mechanistic study reveals that deletion of MLKL significantly increases the activation of autophagy, thereby protecting against hepatocarcinogenesis. MLKL directly interacts with AMPKα1 and inhibits its activity independent of its necroptotic function. Mechanistically, MLKL serves as a bridging molecule between AMPKα1 and protein phosphatase 1B (PPM1B), thus enhancing the dephosphorylation of AMPKα1. Consistently, MLKL expression correlates negatively with AMPKα1 phosphorylation in HCC patients. Taken together, our findings highlight MLKL as a novel AMPK gatekeeper that plays key roles in inhibiting autophagy and driving hepatocarcinogenesis, suggesting that the MLKL-AMPKα1 axis is a potential therapeutic target for HCC.
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Proteínas Quinases Ativadas por AMP , Autofagia , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Quinases , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Humanos , Proteínas Quinases/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Camundongos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/induzido quimicamente , Dietilnitrosamina/toxicidade , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinogênese/genética , Fosforilação , Camundongos Endogâmicos C57BL , Masculino , Camundongos KnockoutRESUMO
BACKGROUND: The renal proximal tubule (RPT) plays a pivotal role in regulating sodium reabsorption and thus blood pressure (BP). Transient receptor potential ankyrin 1 (TRPA1) has been reported to protect against renal injury by modulating mitochondrial function. We hypothesize that the activation of TRPA1 by its agonist cinnamaldehyde may mitigate high-salt intake-induced hypertension by inhibiting urinary sodium reabsorption through restoration of renal tubular epithelial mitochondrial function. METHODS: Trpa1-deficient (Trpa1-/-) mice and wild-type (WT) mice were fed standard laboratory chow [normal diet (ND) group, 0.4% salt], standard laboratory chow with 8% salt [high-salt diet (HS) group], or standard laboratory chow with 8% salt plus 0.015% cinnamaldehyde [high-salt plus cinnamaldehyde diet (HSC) group] for 6 months. Urinary sodium excretion, reactive oxygen species (ROS) production, mitochondrial function, and the expression of sodium hydrogen exchanger isoform 3 (NHE3) and Na+/K+-ATPase of RPTs were determined. RESULTS: Chronic dietary cinnamaldehyde supplementation reduced tail systolic BP and 24-hour ambulatory arterial pressure in HS-fed WT mice. Compared with the mice fed HS, cinnamaldehyde supplementation significantly increased urinary sodium excretion, inhibited excess ROS production, and alleviated mitochondrial dysfunction of RPTs in WT mice. However, these effects of cinnamaldehyde were absent in Trpa1-/- mice. Furthermore, chronic dietary cinnamaldehyde supplementation blunted HS-induced upregulation of NHE3 and Na+/K+-ATPase in WT mice but not Trpa1-/- mice. CONCLUSIONS: The present study demonstrated that chronic activation of Trpa1 attenuates HS-induced hypertension by inhibiting urinary sodium reabsorption through restoring renal tubular epithelial mitochondrial function. Renal TRPA1 may be a potential target for the management of excessive dietary salt intake-associated hypertension.
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Acroleína , Hipertensão , Camundongos Knockout , Mitocôndrias , Cloreto de Sódio na Dieta , Canal de Cátion TRPA1 , Animais , Canal de Cátion TRPA1/metabolismo , Canal de Cátion TRPA1/genética , Acroleína/análogos & derivados , Acroleína/farmacologia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , ATPase Trocadora de Sódio-Potássio/metabolismo , Modelos Animais de Doenças , Espécies Reativas de Oxigênio/metabolismo , Trocador 3 de Sódio-Hidrogênio/metabolismo , Trocador 3 de Sódio-Hidrogênio/genética , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Camundongos , Pressão Sanguínea/efeitos dos fármacosRESUMO
Photosensitizers have been widely used to cause intratumoral generation of reactive oxygen species (ROS) for cancer therapy, but they are easily disturbed by the autophagy pathway, a self-protective mechanism by mitigating oxidative damage. Hereby, we reported a simple and effective strategy to construct a carrier-free nanodrug, Ce6@CQ namely, based on the self-assembly of the photosensitizer chlorin e6 (Ce6) and the autophagy inhibitor chloroquine (CQ). Specifically, Ce6@CQ avoided the unexpected toxicity caused by the regular nanocarrier and also ameliorated its stability in different conditions. Light-activated Ce6 generated cytotoxic ROS and elicited part of the immunogenic cell death (ICD). Moreover, CQ induced autophagy dysfunction, which hindered self-healing in tumor cells and enhanced photodynamic therapy (PDT) to exert a more potent killing effect and more efficient ICD. Also, Ce6@CQ could effectively accumulate in the xenograft breast tumor site in a mouse model through the enhanced permeability and retention (EPR) effect, and the growth of breast tumors was effectively inhibited by Ce6@CQ with light. Such a carrier-free nanodrug provided a new strategy to improve the efficacy of PDT via the suppression of autophagy to digest ROS-induced toxic substances.
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Neoplasias da Mama , Nanopartículas , Fotoquimioterapia , Porfirinas , Animais , Camundongos , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Morte Celular Imunogênica , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Autofagia , Porfirinas/farmacologia , Porfirinas/uso terapêuticoRESUMO
BACKGROUND: Roux-en-Y gastric bypass (RYGB) surgery is an effective metabolic surgery against diabetes and obesity. Clinical evidence indicates that patients with severe obesity have a poor curative effect in losing weight if they suffer from leptin or its receptor deficiency, but the underlying mechanism remains elusive. Here, we investigated the effect of leptin receptor deficiency on metabolic dysfunction in db/db mice treated by RYGB surgery. METHODS: The db/db mice and their heterozygote control db/m mice were subjected to RYGB or sham surgery. Body weight, blood glucose, food intake and glucose tolerance were evaluated. Micro-PET/CT and histological analysis were performed to examine the glucose uptake of tissues and the fat changes in mice. The key factors in glucose and fatty acid metabolism were detected by western blot analysis. RESULTS: Compared with the sham group, the db/db mice in the RYGB group showed more significant weight regain after surgical recovery and improvement in hyperinsulinemia and glucose tolerance. However, the total body fat and multiple organ lipid deposition of RYGB-treated db/db mice was increased. The underlying mechanism studies suggested that the activation of AMPK regulated GLUT4 to increase glucose uptake, but AMPK could not promote fatty acid oxidation through the JAK2/STAT3 pathway under leptin receptor deficiency in db/db mice. CONCLUSION: We conclude that leptin receptor deficiency impedes the AMPK activation-mediated fat catabolism but does not affect AMPK-related glucose utilization after metabolic surgery in db/db mice. This result helps select surgical indications for patients with obesity and diabetes.
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INTRODUCTION: Excess salt intake is not only an independent risk factor for heart failure, but also one of the most important dietary factors associated with cardiovascular disease worldwide. Metabolic reprogramming in cardiomyocytes is an early event provoking cardiac hypertrophy that leads to subsequent cardiovascular events upon high salt loading. Although SGLT2 inhibitors, such as canagliflozin, displayed impressive cardiovascular health benefits, whether SGLT2 inhibitors protect against cardiac hypertrophy-related metabolic reprogramming upon salt loading remain elusive. OBJECTIVES: To investigate whether canagliflozin can improve salt-induced cardiac hypertrophy and the underlying mechanisms. METHODS: Dahl salt-sensitive rats developed cardiac hypertrophy by feeding them an 8% high-salt diet, and some rats were treated with canagliflozin. Cardiac function and structure as well as mitochondrial function were examined. Cardiac proteomics, targeted metabolomics and SIRT3 cardiac-specific knockout mice were used to uncover the underlying mechanisms. RESULTS: In Dahl salt-sensitive rats, canagliflozin showed a potent therapeutic effect on salt-induced cardiac hypertrophy, accompanied by lowered glucose uptake, reduced accumulation of glycolytic end-products and improved cardiac mitochondrial function, which was associated with the recovery of cardiac expression of SIRT3, a key mitochondrial metabolic regulator. Cardiac-specific knockout of SIRT3 not only exacerbated salt-induced cardiac hypertrophy but also abolished the therapeutic effect of canagliflozin. Mechanistically, high salt intake repressed cardiac SIRT3 expression through a calcium-dependent epigenetic modifications, which could be blocked by canagliflozin by inhibiting SGLT1-mediated calcium uptake. SIRT3 improved myocardial metabolic reprogramming by deacetylating MPC1 in cardiomyocytes exposed to pro-hypertrophic stimuli. Similar to canagliflozin, the SIRT3 activator honokiol also exerted therapeutic effects on cardiac hypertrophy. CONCLUSION: Cardiac mitochondrial dysfunction caused by SIRT3 repression is a critical promotional determinant of metabolic pattern switching underlying salt-induced cardiac hypertrophy. Improving SIRT3-mediated mitochondrial function by SGLT2 inhibitors-mediated calcium handling would represent a therapeutic strategy against salt-related cardiovascular events.
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OBJECTIVE: Aberrant activating mutations in cyclin-dependent kinases 4 and 6 (CDK4/6) are common in various cancers, including gastroesophageal malignancies. Although CDK4/6 inhibitors, such as abemaciclib and palbociclib, have been approved for breast cancer treatment, their effectiveness as a monotherapy remains limited for gastroesophageal tumors. The present study explored the underlying mechanism of abemaciclib resistance. METHODS: Abemaciclib-resistant gastric cancer cell lines were generated, and the phospho-eukaryotic translation initiation factor 4E (p-eIF4E) and eIF4E expression was compared between resistant and parental cell lines. In order to analyze the role of eIF4E in cell resistance, siRNA knockdown was employed. The effectiveness of ribavirin alone and its combination with abemaciclib was evaluated in the gastric cancer xenograft mouse model. RESULTS: The upregulation of eIF4E was a common feature in gastric cancer cells exposed to prolonged abemaciclib treatment. Gastric cancer cells with increased eIF4E levels exhibited a better response to eIF4E inhibition, especially those that were resistant to abemaciclib. Ribavirin, which is an approved anti-viral drug, significantly improved the efficacy of abemaciclib, both in vitro and in vivo, by inhibiting eIF4E. Importantly, ribavirin effectively suppressed the abemaciclib-resistant gastric cancer growth in mice without causing toxicity. CONCLUSION: These findings suggest that targeting eIF4E can enhance the abemaciclib treatment for gastric cancer, proposing the potential combination therapy of CDK4/6 inhibitors with ribavirin for advanced gastric cancer.
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Aminopiridinas , Resistencia a Medicamentos Antineoplásicos , Ribavirina , Neoplasias Gástricas , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Aminopiridinas/uso terapêuticoRESUMO
Immunotherapy is a revolutionary and promising approach to cancer treatment. However, traditional cancer immunotherapy often has the disadvantages of limited immune response rate, poor targeting, and low treatment index due to systemic administration. Hydrogels are drug carriers with many advantages. They can be loaded and transported with immunotherapeutic agents, chemical anticancer drugs, radiopharmaceuticals, photothermal agents, photosensitizers, and other therapeutic agents to achieve controlled release of drugs, extend the retention time of drugs, and thus successfully trigger anti-tumor effects and maintain long-term therapeutic effects after administration. This paper reviews recent advances in injectable hydrogel-based cancer immunotherapy, including immunotherapy alone, immunotherapy with combination chemotherapy, radiotherapy, phototherapy, and DNA hydrogel-based immunotherapy. Finally, we review the potential and limitations of injectable hydrogels in cancer immunotherapy.
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Photothermal therapy (PTT) is an emerging field where photothermal agents could convert visible or near-infrared (NIR) radiation into heat to kill tumor cells. However, the low photothermal conversion efficiency of photothermal agents and their limited antitumor activities hinder the development of these agents into monotherapies for cancer. Herein, we have fabricated an ultrasmall polyvinylpyrrolidone (PVP)-Fe-Cu-Ni-S (PVP-NP) nano-agent via a simple hot injection method with excellent photothermal conversion efficiency (â¼96%). Photothermal therapy with this nano-agent effectively inhibits tumor growth without apparent toxic side-effects. Mechanistically, our results demonstrated that, after NIR irradiation, PVP-NPs can induce ROS/singlet oxygen generation, decrease the mitochondrial membrane potential, release extracellular Fe2+, and consume glutathione, triggering autophagy and ferroptosis of cancer cells. Moreover, PVP-NPs exhibit excellent contrast enhancement according to magnetic resonance imaging (MRI) analysis. In summary, PVP-NPs have a high photothermal conversion efficiency and can be applied for MRI-guided synergistic photothermal/photodynamic/chemodynamic cancer therapy, resolving the bottleneck of existing phototherapeutic agents.
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Ferroptose , Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Povidona/farmacologia , Nanomedicina Teranóstica/métodos , Fotoquimioterapia/métodos , Fototerapia/métodos , Neoplasias/tratamento farmacológico , Autofagia , Nanopartículas/uso terapêutico , Linhagem Celular TumoralRESUMO
[This retracts the article DOI: 10.1515/med-2022-0417.].