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1.
J Magn Reson Imaging ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609076

RESUMO

BACKGROUND: Lymph node metastasis (LNM) in patients with intrahepatic cholangiocarcinoma (iCCA) affects treatment strategies and prognosis. However, preoperative imaging is not reliable enough for identifying LNM. PURPOSE: To develop and validate a radiomics nomogram based on dynamic contrast enhanced (DCE)-MR images for identifying LNM and prognosis in iCCA. STUDY TYPE: Retrospective. SUBJECTS: Two hundred four patients with pathologically proven iCCA who underwent curative-intent resection and lymphadenectomy (training cohort: N = 107, internal test cohort: N = 46, and external test cohort: N = 51). FIELD STRENGTH/SEQUENCE: T1- and T2-weighted imaging, diffusion-weighted imaging and DCE imaging at 1.5 T or 3.0 T. ASSESSMENT: Radiomics features were extracted from intra- and peri-tumoral regions on preoperative DCE-MR images. Imaging features were evaluated by three radiologists, and significant variables in univariable and multivariable regression analysis were included in clinical model. The best-performing radiomics signature and clinical characteristics (intrahepatic duct dilatation, MRI-reported LNM) were combined to build a nomogram. Patients were divided into high-risk and low-risk groups based on their nomogram scores (cutoff = 0.341). Patients were followed up for 1-102 months (median 12) after surgery, the overall survival (OS) and recurrence-free survival (RFS) were calculated. STATISTICAL TESTS: Receiver operating characteristic (ROC) curve, calibration, decision curve, Delong test, Kaplan-Meier curves, log rank test. Two tailed P < 0.05 was considered statistically significant. RESULTS: The nomogram incorporating intra- and peri-tumoral radiomics features, intrahepatic duct dilatation and MRI-reported LNM obtained the best discrimination for LNM, with areas under the ROC curves of 0.946, 0.913, and 0.859 in the training, internal, and external test cohorts. In the entire cohort, high-risk patients had significantly lower RFS and OS than low-risk patients. High-risk of LNM was an independent factor of unfavorable OS and RFS. DATA CONCLUSION: The nomogram integrating intra- and peri-tumoral radiomics signatures has potential to identify LNM and prognosis in iCCA. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

2.
Curr Pharm Des ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38482629

RESUMO

INTRODUCTION: Although anthracyclines have demonstrated efficacy in cancer therapy, their utilization is constrained by cardiotoxicity. In contrast, Danshen injection (DSI), derived from Salvia miltiorrhiza, has a longstanding tradition of being employed to ameliorate cardiovascular ailments, including anthracycline- induced cardiotoxicity (AIC). Nonetheless, there is a notable dearth of comprehensive systematic investigation into the molecular mechanisms underlying DSI's effects on AIC. Consequently, this study was undertaken to explore the underlying mechanism by which DSI acted against AIC. METHODS: Employing network pharmacology approach, the current investigation undertook a comprehensive analysis of the impact of DSI on AIC, which was further validated by transcriptome sequencing with in vitro AIC model. Additionally, molecular docking was conducted to evaluate the binding of active ingredients to core targets. A total of 3,404 AIC-related targets and 12 active ingredients in DSI, including chrysophanol, luteolin, tanshinone IIA, isoimperatorin, among others, were collected by differentially expressed analysis and database search, respectively. RESULTS: The network pharmacology and enrichment analysis suggested 102 potential targets and 29 signaling pathways associated with the protective effect of DSI on AIC. Three core targets (CA12, NOS3, and POLH) and calcium signaling pathways were further validated by transcriptomic analysis of the in-vitro model. The high affinity of the active ingredients binding to corresponding targets was confirmed by molecular docking. CONCLUSION: The present study suggested that DSI might exert a cardioprotective effect on AIC via the inhibition of CA12, NOS3, and POLH, as well as the modulation of calcium signaling. Further experiments are warranted to verify the findings.

3.
Sci Rep ; 14(1): 4409, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388563

RESUMO

Despite recent advances in science and medical technology, pancreatic cancer remains associated with high mortality rates due to aggressive growth and no early clinical sign as well as the unique resistance to anti-cancer chemotherapy. Current numerous investigations have suggested that ferroptosis, which is a programed cell death driven by lipid oxidation, is an attractive therapeutic in different tumor types including pancreatic cancer. Here, we first demonstrated that linoleic acid (LA) and α-linolenic acid (αLA) induced cell death with necroptotic morphological change in MIA-Paca2 and Suit 2 cell lines. LA and αLA increased lipid peroxidation and phosphorylation of RIP3 and MLKL in pancreatic cancers, which were negated by ferroptosis inhibitor, ferrostatin-1, restoring back to BSA control levels. Similarly, intraperitoneal administration of LA and αLA suppresses the growth of subcutaneously transplanted Suit-2 cells and ameliorated the decreased survival rate of tumor bearing mice, while co-administration of ferrostatin-1 with LA and αLA negated the anti-cancer effect. We also demonstrated that LA and αLA partially showed ferroptotic effects on the gemcitabine-resistant-PK cells, although its effect was exerted late compared to treatment on normal-PK cells. In addition, the trial to validate the importance of double bonds in PUFAs in ferroptosis revealed that AA and EPA had a marked effect of ferroptosis on pancreatic cancer cells, but DHA showed mild suppression of cancer proliferation. Furthermore, treatment in other tumor cell lines revealed different sensitivity of PUFA-induced ferroptosis; e.g., EPA induced a ferroptotic effect on colorectal adenocarcinoma, but LA or αLA did not. Collectively, these data suggest that PUFAs can have a potential to exert an anti-cancer effect via ferroptosis in both normal and gemcitabine-resistant pancreatic cancer.


Assuntos
Cicloexilaminas , Ferroptose , Neoplasias Pancreáticas , Fenilenodiaminas , Camundongos , Animais , Gencitabina , Ácidos Graxos Insaturados/farmacologia , Ácidos Graxos Insaturados/metabolismo , Ácido Linoleico , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia
4.
Sci Rep ; 14(1): 4364, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388558

RESUMO

An inverse association between cancer and Alzheimer's disease (AD) has been demonstrated; however, the association between cancer and mild cognitive impairment (MCI), and the association between cancer and cognitive decline are yet to be clarified. The AIBL dataset was used to address these knowledge gaps. The crude and adjusted odds ratios for MCI/AD and cognitive decline were compared between participants with/without cancer (referred to as C+ and C- participants). A 37% reduction in odds for AD was observed in C+ participants compared to C- participants after adjusting for all confounders. The overall risk for MCI and AD in C+ participants was reduced by 27% and 31%, respectively. The odds of cognitive decline from MCI to AD was reduced by 59% in C+ participants after adjusting for all confounders. The risk of cognitive decline from MCI to AD was halved in C+ participants. The estimated mean change in Clinical Dementia Rating-Sum of boxes (CDR-SOB) score per year was 0.23 units/year higher in C- participants than in C+ participants. Overall, an inverse association between cancer and MCI/AD was observed in AIBL, which is in line with previous reports. Importantly, an inverse association between cancer and cognitive decline has also been identified.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Neoplasias , Humanos , Testes Neuropsicológicos , Austrália/epidemiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/psicologia , Biomarcadores , Estilo de Vida , Neoplasias/complicações , Neoplasias/epidemiologia , Progressão da Doença
5.
J Alzheimers Dis ; 97(1): 89-100, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38007665

RESUMO

The accumulation of amyloid-ß (Aß) plaques in the brain is considered a hallmark of Alzheimer's disease (AD). Mathematical modeling, capable of predicting the motion and accumulation of Aß, has obtained increasing interest as a potential alternative to aid the diagnosis of AD and predict disease prognosis. These mathematical models have provided insights into the pathogenesis and progression of AD that are difficult to obtain through experimental studies alone. Mathematical modeling can also simulate the effects of therapeutics on brain Aß levels, thereby holding potential for drug efficacy simulation and the optimization of personalized treatment approaches. In this review, we provide an overview of the mathematical models that have been used to simulate brain levels of Aß (oligomers, protofibrils, and/or plaques). We classify the models into five categories: the general ordinary differential equation models, the general partial differential equation models, the network models, the linear optimal ordinary differential equation models, and the modified partial differential equation models (i.e., Smoluchowski equation models). The assumptions, advantages and limitations of these models are discussed. Given the popularity of using the Smoluchowski equation models to simulate brain levels of Aß, our review summarizes the history and major advancements in these models (e.g., their application to predict the onset of AD and their combined use with network models). This review is intended to bring mathematical modeling to the attention of more scientists and clinical researchers working on AD to promote cross-disciplinary research.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Modelos Teóricos , Encéfalo/patologia , Simulação por Computador , Placa Amiloide/patologia
6.
Gels ; 9(9)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37754440

RESUMO

In the present study, flaxseed gum (FG), Arabic gum (GA) and Tween 80 were used to prepare oleogels through an emulsion-templated method, and the obtained oleogels were designed for the partial substitution of pork fat in emulsified sausage. An increment in FG concentrations enhanced the viscoelasticity of emulsions, which resulted in the improved stability of emulsion systems, with smaller droplet sizes. In addition, increased FG concentrations contributed to higher mechanical strength, denser network structure and lower oil loss of oleogels. As a fat substitute, the prepared oleogels improved the textural properties and nutritional quality of emulsified sausages. With the increase in the substitution level of oleogels, the hardness and chewiness of the emulsified sausage increased, and the cooking loss decreased. Meanwhile, the reformulation with oleogels decreased the saturated fat from 57.04 g/100 g lipid to 12.05 g/100 g lipid, while increasing the ratio of omega-6 to omega-3 essential fatty acids from 0.10 to 0.39. The obtained results demonstrated that the flaxseed gum/Arabic gum/Tween 80-based oleogels had huge potential to successfully replace pork fat in emulsified sausage products.

7.
Pharmaceutics ; 15(8)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37631298

RESUMO

P-glycoprotein (P-gp), expressed at the blood-brain barrier (BBB), is critical in preventing brain access to substrate drugs and effluxing amyloid beta (Aß), a contributor to Alzheimer's disease (AD). Strategies to regulate P-gp expression therefore may impact central nervous system (CNS) drug delivery and brain Aß levels. As we have demonstrated that the copper complex copper diacetyl bis(4-methyl-3-thiosemicarbazone) (Cu(ATSM)) increases P-gp expression and function in human brain endothelial cells, the present study assessed the impact of Cu(ATSM) on expression and function of P-gp in mouse brain endothelial cells (mBECs) and capillaries in vivo, as well as in peripheral organs. Isolated mBECs treated with Cu(ATSM) (100 nM for 24 h) exhibited a 1.6-fold increase in P-gp expression and a 20% reduction in accumulation of the P-gp substrate rhodamine 123. Oral administration of Cu(ATSM) (30 mg/kg/day) for 28 days led to a 1.5 & 1.3-fold increase in brain microvascular and hepatic expression of P-gp, respectively, and a 20% reduction in BBB transport of [3H]-digoxin. A metallomic analysis showed a 3.5 and 19.9-fold increase in Cu levels in brain microvessels and livers of Cu(ATSM)-treated mice. Our findings demonstrate that Cu(ATSM) increases P-gp expression and function at the BBB in vivo, with implications for CNS drug delivery and clearance of Aß in AD.

8.
J Neuroimmune Pharmacol ; 18(3): 448-461, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37555918

RESUMO

Prolonged activation of microglia leads to excessive release of proinflammatory mediators, which are detrimental to brain health. Therefore, there are significant efforts to identify pathways mediating microglial activation. Recent studies have demonstrated that fatty acid-binding protein 4 (FABP4), a lipid binding protein, is a critical player in macrophage-mediated inflammation. Given that we have previously identified FABP4 in microglia, the aim of this study was to assess whether FABP4 activity contributed to inflammation, metabolism and immune function (i.e. immunometabolism) in immortalised mouse microglia (BV-2 cells) using the proinflammatory stimulus lipopolysaccharide (LPS) to induce general microglial activation. Microglial FABP4 expression was significantly increased following exposure to LPS, an outcome associated with a significant increase in microglial proliferation rate. LPS-stimulated BV-2 microglia demonstrated a significant increase in the production of reactive oxygen species (ROS) and tumour necrosis factor-alpha (TNF-α), phosphorylation of c-Jun N-terminal kinase (JNK), increased expression of Toll-like receptor 4 (TLR4), and reduced expression of uncoupling protein 2 (UCP2), all of which were reversed following FABP4 genetic silencing and chemical inhibition with BMS309403. The oxidation rate of 3H-oleic acid and microglial uptake of 3H-2-deoxy-D-glucose were modulated with LPS activation, processes which were restored with genetic and chemical inhibition of FABP4. This is the first study to report on the critical role of FABP4 in mediating the deleterious effects of LPS on microglial immunometabolism, suggesting that FABP4 may present as a novel therapeutic target to alleviate microglia-mediated neuroinflammation, a commonly reported factor in multiple neurodegenerative diseases.


Assuntos
Lipopolissacarídeos , Microglia , Animais , Camundongos , Encéfalo/metabolismo , Proteínas de Ligação a Ácido Graxo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade
9.
Neurotherapeutics ; 20(4): 1198-1214, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37226029

RESUMO

Increased expression of the voltage-gated potassium channel Kv1.3 in activated microglia, and the subsequent release of pro-inflammatory mediators, are closely associated with the progression of Alzheimer's disease (AD). Studies have shown that reducing neuroinflammation through the non-selective blockade of microglial Kv1.3 has the potential to improve cognitive function in mouse models of familial AD. We have previously demonstrated that a potent and highly-selective peptide blocker of Kv1.3, HsTX1[R14A], not only entered the brain parenchyma after peripheral administration in a lipopolysaccharide (LPS)-induced mouse model of inflammation, but also significantly reduced pro-inflammatory mediator release from activated microglia. In this study, we show that microglial expression of Kv1.3 is increased in senescence accelerated mice (SAMP8), an animal model of sporadic AD, and that subcutaneous dosing of HsTX1[R14A] (1 mg/kg) every other day for 8 weeks provided a robust improvement in cognitive deficits in SAMP8 mice. The effect of HsTX1[R14A] on the whole brain was assessed using transcriptomics, which revealed that the expression of genes associated with inflammation, neuron differentiation, synapse function, learning and memory were altered by HsTX1[R14A] treatment. Further study is required to investigate whether these changes are downstream effects of microglial Kv1.3 blockade or a result of alternative mechanisms, including any potential effect of Kv1.3 blockade on other brain cell types. Nonetheless, these results collectively demonstrate the cognitive benefits of Kv1.3 blockade with HsTX1[R14A] in a mouse model of sporadic AD, demonstrating its potential as a therapeutic candidate for this neurodegenerative disease.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Animais , Peptídeos/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Modelos Animais de Doenças , Inflamação , Cognição
10.
Eur Radiol ; 33(9): 5993-6000, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37014407

RESUMO

OBJECTIVES: To compare the clinical and MRI features of primary hepatic lymphoepithelioma-like carcinoma (LELC) categorized as LR-M or LR-4/5 using the Liver Imaging Reporting and Data System (LI-RADS) version 2018 and to determine the prognostic factors for recurrence-free survival (RFS). METHODS: In this retrospective study, 37 patients with surgically confirmed LELC were included. Two independent observers evaluated preoperative MRI features according to the LI-RADS version 2018. Clinical and imaging features were compared between two groups. RFS and the associated factors were evaluated using Cox proportional hazards regression analysis, Kaplan-Meier analysis, and log-rank test. RESULTS: In total, 37 patients (mean age, 58.5 ± 10.3 years) were evaluated. Sixteen (43.2%) LELCs were categorized as LR-M and twenty-one (56.8%) LELCs were categorized as LR-4/5. In the multivariate analysis, the LR-M category was an independent factor for RFS (HR 7.908, 95% CI 1.170-53.437; p = 0.033). RFS rates were significantly lower in patients with LR-M LELCs than in patients with LR-4/5 LELCs (5-year RFS rate, 43.8% vs.85.7%; p = 0.002). CONCLUSION: The LI-RADS category was significantly associated with postsurgical prognosis of LELC, with tumor categorized as LR-M having a worse RFS than those categorized as LR-4/5. KEY POINTS: • Lymphoepithelioma-like carcinoma patients categorized as LR-M have worse recurrence-free survival than those categorized as LR-4/5. • MRI-based LI-RADS categorization was an independent factor for postoperative prognosis of primary hepatic lymphoepithelioma-like carcinoma.


Assuntos
Carcinoma Hepatocelular , Carcinoma de Células Escamosas , Neoplasias Hepáticas , Humanos , Pessoa de Meia-Idade , Idoso , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Prognóstico , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Meios de Contraste , Sensibilidade e Especificidade
11.
Int J Dev Neurosci ; 83(3): 257-266, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36808642

RESUMO

PURPOSE: To explore the application value of voxel-based morphometric (VBM) in prenatal diagnosis of microcephaly. METHODS: A retrospective study of magnetic resonance imaging of fetuses with microcephaly was performed using a single-shot fast spin echo sequence; semiautomatic segmentation of grey matter (GM), white matter (WM), and cerebrospinal fluid (CSF); calculation of their volumes; and VBM analysis of their GM. Two independent samples t-test was used to statistically analyse the fetal GM volume in the microcephaly and normal control groups. Total intracranial volume (TIV), GM volume, WM volume, and CSF volume were linearly regressed against gestational age and compared between the two groups. RESULTS: In the fetus with microcephaly, GM volume of frontal lobe, temporal lobe, cuneus, anterior central gyrus, and posterior central gyrus decreased significantly (P < 0.001, corrected by family-wise error at mass level). The GM volume of microcephaly was significantly lower than that of the control group (except for 28 weeks of gestation) (P < 0.05). TIV, GM volume, WM volume, and CSF volume were all positively correlated with gestational age, and the curves in the microcephaly group were all lower than those in the control group. CONCLUSION: Compared with the normal control group, the GM volume of microcephaly fetuses decreased, and there were significant differences in many brain regions through VBM analysis.


Assuntos
Microcefalia , Malformações do Sistema Nervoso , Humanos , Gravidez , Feminino , Microcefalia/diagnóstico por imagem , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética/métodos , Feto/diagnóstico por imagem
12.
Int J Cardiovasc Imaging ; 39(1): 161-168, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36598697

RESUMO

To evaluate the prognostic value of aortic distensibility measured by cardiovascular magnetic resonance (CMR) as predictors of prophylactic aortic valve or aortic surgery in patients with bicuspid aortic valve (BAV). 110 patients with BAV were included. Distensibility of middle ascending aorta (AscAo) and proximal descending aorta (DescAo) at baseline was determined using CMR. The association between aortic distensibility and primary endpoint of aortic valve and/or aortic surgery was investigated with Cox proportional hazard regression analyses. The receiver operating characteristics curves (ROC) of the area under receiver-operator (AUC) and DeLong test were used to evaluate and compare the performance of different models. During a median follow-up of 66.5 months [IQR 13-75 months], 42 patients experienced surgical treatments. After adjusting for traditional risk factors, aortic distensibility (P = 0.003) and severe valve dysfunction (P < 0.001) were found significantly associated with aortic valve and/or aortic surgery. The model 2 (aortic distensibility and severe valve dysfunction) is slightly better in predicting primary endpoint than the model 1 (aortic diameter and severe valve dysfunction) (AUC: 0.893 vs. 0.842, P = 0.106). In BAV patients, aortic distensibility and severe valve dysfunction are valuable predictors for final aortic valve and/or aortic surgery.


Assuntos
Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Humanos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Valva Aórtica/patologia , Doença da Válvula Aórtica Bicúspide/complicações , Doença da Válvula Aórtica Bicúspide/patologia , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/cirurgia , Valor Preditivo dos Testes , Prognóstico , Imageamento por Ressonância Magnética
13.
Food Chem ; 402: 134198, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36116277

RESUMO

Oil body (OB) is the lipid-storage organelle in oilseed, and its stability is crucial for oilseed processing. Herein, effects of roasting and boiling on the structure, stability, and in vitro lipid digestion of Camellia OB were studied. The interfacial structure and physical stability of the extracted OB were investigated by electrophoresis, confocal-Raman spectroscopy, zeta-potential, and surface hydrophobicity, etc. Boiling caused protein loss on the OB surfaces, forming a stable phospholipid interface, which resulted in coalescence of the droplets (d > 100 µm) and negative ζ-potential (-3 âˆ¼ -8 mV) values at a pH of 2.0. However, roasting partially denatured the proteins in the seeds, which were adsorbed on the OB surfaces. The random coil structure of interfacial protein increased to ∼20 % after thermal treatment. Besides, heating decreased the surface hydrophobicity of OB and improved lipid digestion. After boiling 60 min, the extent of lipolysis increased from 41.7 % (raw) to 57.4 %.


Assuntos
Camellia , Gotículas Lipídicas , Gotículas Lipídicas/química , Camellia/metabolismo , Óleos de Plantas/química , Digestão , Fosfolipídeos/análise , Emulsões/química
14.
FEBS J ; 290(7): 1798-1821, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36325660

RESUMO

Fatty acid-binding protein 7 (FABP7), one of the fatty acid (FA) chaperones involved in the modulation of intracellular FA metabolism, is highly expressed in glioblastoma, and its expression is associated with decreased patients' prognosis. Previously, we demonstrated that FABP7 requires its binding partner to exert its function and that a mutation in the FA-binding site of FABP7 affects tumour biology. Here, we explored the role of FA ligand binding for FABP7 function in tumour proliferation and examined the mechanism of FABP7 and ligand interaction in tumour biology. We discovered that among several FA treatment, oleic acid (OA) boosted cell proliferation of FABP7-expressing cells. In turn, OA increased FABP7 nuclear localization, and the accumulation of FABP7-OA complex in the nucleus induced the formation of nuclear lipid droplet (nLD), as well as an increase in colocalization of nLD with promyelocytic leukaemia (PML) nuclear bodies. Furthermore, OA increased mRNA levels of proliferation-related genes in FABP7-expressing cells through histone acetylation. Interestingly, these OA-boosted functions were abrogated in FABP7-knockout cells and mutant FABP7-overexpressing cells. Thus, our findings suggest that FABP7-OA intracellular interaction may modulate nLD formation and the epigenetic status thereby enhancing transcription of proliferation-regulating genes, ultimately driving tumour cell proliferation.


Assuntos
Glioma , Ácido Oleico , Humanos , Proteína 7 de Ligação a Ácidos Graxos/genética , Proteína 7 de Ligação a Ácidos Graxos/metabolismo , Ácido Oleico/farmacologia , Ácido Oleico/metabolismo , Gotículas Lipídicas/metabolismo , Ligantes , Glioma/patologia , Proliferação de Células , Proteínas Supressoras de Tumor/genética
15.
Pharmaceutics ; 14(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36559296

RESUMO

For peripherally administered drugs to reach the central nervous system (CNS) and treat amyotrophic lateral sclerosis (ALS), they must cross the blood-brain barrier (BBB). As mounting evidence suggests that the ultrastructure of the BBB is altered in individuals with ALS and in animal models of ALS (e.g., SOD1G93A mice), we characterized BBB transporter expression and function in transgenic C9orf72 BAC (C9-BAC) mice expressing a hexanucleotide repeat expansion, the most common genetic cause of ALS. Using an in situ transcardiac brain perfusion technique, we identified a 1.4-fold increase in 3H-2-deoxy-D-glucose transport across the BBB in C9-BAC transgenic (C9) mice, relative to wild-type (WT) mice, which was associated with a 1.3-fold increase in brain microvascular glucose transporter 1 expression, while other general BBB permeability processes (passive diffusion, efflux transporter function) remained unaffected. We also performed proteomic analysis on isolated brain microvascular endothelial cells, in which we noted a mild (14.3%) reduction in zonula occludens-1 abundance in C9 relative to WT mice. Functional enrichment analysis highlighted trends in changes to various BBB transporters and cellular metabolism. To our knowledge, this is the first study to demonstrate altered BBB function in a C9orf72 repeat expansion model of ALS, which has implications on how therapeutics may access the brain in this mouse model.

16.
Bioconjug Chem ; 33(11): 2197-2212, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36330854

RESUMO

Upregulation of the voltage-gated potassium channel KV1.3 is implicated in a range of autoimmune and neuroinflammatory diseases, including rheumatoid arthritis, psoriasis, multiple sclerosis, and type I diabetes. Understanding the expression, localization, and trafficking of KV1.3 in normal and disease states is key to developing targeted immunomodulatory therapies. HsTX1[R14A], an analogue of a 34-residue peptide toxin from the scorpion Heterometrus spinifer, binds KV1.3 with high affinity (IC50 of 45 pM) and selectivity (2000-fold for KV1.3 over KV1.1). We have synthesized a fluorescent analogue of HsTX1[R14A] by N-terminal conjugation of a Cy5 tag. Electrophysiology assays show that Cy5-HsTX1[R14A] retains activity against KV1.3 (IC50 ∼ 0.9 nM) and selectivity over a range of other potassium channels (KV1.2, KV1.4, KV1.5, KV1.6, KCa1.1 and KCa3.1), as well as selectivity against heteromeric channels assembled from KV1.3/KV1.5 tandem dimers. Live imaging of CHO cells expressing green fluorescent protein-tagged KV1.3 shows co-localization of Cy5-HsTX1[R14A] and KV1.3 fluorescence signals at the cell membrane. Moreover, flow cytometry demonstrated that Cy5-HsTX1[R14A] can detect KV1.3-expressing CHO cells. Stimulation of mouse microglia by lipopolysaccharide, which enhances membrane expression of KV1.3, was associated with increased staining by Cy5-HsTX1[R14A], demonstrating that it can be used to identify KV1.3 in disease-relevant models of inflammation. Furthermore, the biodistribution of Cy5-HsTX1[R14A] could be monitored using ex vivo fluorescence imaging of organs in mice dosed subcutaneously with the peptide. These results illustrate the utility of Cy5-HsTX1[R14A] as a tool for visualizing KV1.3, with broad applicability in fundamental investigations of KV1.3 biology, and the validation of novel disease indications where KV1.3 inhibition may be of therapeutic value.


Assuntos
Canal de Potássio Kv1.3 , Venenos de Escorpião , Camundongos , Animais , Cricetinae , Canal de Potássio Kv1.3/química , Canal de Potássio Kv1.3/metabolismo , Venenos de Escorpião/química , Venenos de Escorpião/metabolismo , Venenos de Escorpião/farmacologia , Bloqueadores dos Canais de Potássio/química , Bloqueadores dos Canais de Potássio/farmacologia , Cricetulus , Distribuição Tecidual , Peptídeos/química
17.
Adv Drug Deliv Rev ; 185: 114282, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35421522

RESUMO

Alzheimer's disease (AD) has traditionally been considered solely a neurological condition. Therefore, numerous studies have been conducted to identify the existence of pathophysiological changes affecting the brain and the blood-brain barrier in individuals with AD. Such studies have provided invaluable insight into possible changes to the central nervous system exposure of drugs prescribed to individuals with AD. However, there is now increasing recognition that extra-neurological systems may also be affected in AD, such as the small intestine, liver, and kidneys. Examination of these peripheral pathophysiological changes is now a burgeoning area of scientific research, owing to the potential impact of these changes on the absorption, distribution, metabolism, and excretion (ADME) of drugs used for both AD and other concomitant conditions in this population. The purpose of this review is to identify and summarise available literature reporting alterations to key organs influencing the pharmacokinetics of drugs, with any changes to the small intestine, liver, kidney, and circulatory system on the ADME of drugs described. By assessing studies in both rodent models of AD and samples from humans with AD, this review highlights possible dosage adjustment requirements for both AD and non-AD drugs so as to ensure the achievement of optimum pharmacotherapy in individuals with AD.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Humanos , Intestino Delgado/metabolismo
18.
Int J Cardiovasc Imaging ; 38(9): 2025-2033, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35279784

RESUMO

To determine the relationship between aortic distensibility and left ventricular (LV) remodeling, myocardial strain and blood biomarkers in patients with stenotic bicuspid aortic valve (BAV) and preserved ejection fraction (EF) by cardiovascular magnetic resonance (CMR). 43 stenotic BAV patients were prospectively selected for 3.0 T CMR. Patients were divided into LV remodeling group (LV mass/volume ≥ 1.15, n = 21) and non-remodeling group (LV mass/volume < 1.15, n = 22). Clinical characteristics, biochemical data including cardiac troponin T(cTNT), N-terminal pro-B type natriuretic peptide (NT-proBNP) and creatine kinase isoenzyme (CK-MB) were noted. Distensibility of middle ascending aorta (mid-AA) and proximal descending aorta, LV structural and functional parameters, global and regional myocardial strain were measured. Compared to non-remodeling group, LV remodeling group had significantly decreased LV global strain (radial: 26.04 ± 8.70% vs. 32.92 ± 7.81%, P = 0.009; circumferential: - 17.20 ± 3.38% vs. - 19.65 ± 2.34%, P = 0.008; longitudinal: - 9.13 ± 2.34% vs. - 11.63 ± 1.99%, P < 0.001) and decreased mid-AA distensibility (1.22 ± 0.24 10-3 mm/Hg vs 1.60 ± 0.41 10-3 mm/Hg, P = 0.001). In addition, mid-AA distensibility was independently associated with LV remodeling (ß = - 0.282, P = 0.003), and it was also significantly correlated with LV global strain (radial: r = 0.392, P = 0.009; circumferential: r = - 0.348, P = 0.022; longitudinal: r = - 0.333, P = 0.029), cTNT (r = - 0.333, P = 0.029) and NT-proBNP (r = - 0.440, P = 0.003). In this cohort with stenotic BAV and preserved EF, mid-AA distensibility is found significantly associated with LV remolding, which encouraging to better understand mechanism of ventricular vascular coupling.


Assuntos
Doença da Válvula Aórtica Bicúspide , Mercúrio , Humanos , Doença da Válvula Aórtica Bicúspide/patologia , Valva Aórtica , Função Ventricular Esquerda , Valor Preditivo dos Testes , Remodelação Ventricular , Volume Sistólico
19.
Br J Pharmacol ; 179(11): 2577-2588, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35048358

RESUMO

The access of drugs into the central nervous system (CNS) is regulated by the blood-brain barrier (BBB) and blood-spinal cord barrier (BSCB). A large body of evidence supports perturbation of these barriers in neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Modifications to the BBB and BSCB are also reported in amyotrophic lateral sclerosis (ALS), albeit these modifications have received less attention relative to those in other neurodegenerative diseases. Such alterations to the BBB and BSCB have the potential to impact on CNS exposure of drugs in ALS, modulating the effectiveness of drugs intended to reach the brain and the toxicity of drugs that are not intended to reach the brain. Given the clinical importance of these phenomena, this review will summarise reported modifications to the BBB and BSCB in ALS, discuss their impact on CNS drug exposure, and suggest further research directions so as to optimise medicine use in people with ALS.


Assuntos
Esclerose Amiotrófica Lateral , Esclerose Amiotrófica Lateral/tratamento farmacológico , Barreira Hematoencefálica , Sistema Nervoso Central , Humanos , Medula Espinal
20.
J Pharm Sci ; 111(3): 638-647, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34767826

RESUMO

The expression of voltage-gated potassium Kv1.3 channels is increased in activated microglia, with non-selective blockade reported to attenuate microglial-mediated neuroinflammation. In this study, we evaluated the impact of a potent and selective peptidic blocker of Kv1.3 channels, HsTX1[R14A], on microglial-mediated neuroinflammation in vitro and in vivo. Treatment with both 0.1 and 1 µg/mL lipopolysaccharide (LPS) significantly (p < 0.05) increased Kv1.3 abundance on the surface of BV-2 microglia in association with increased levels of mRNA for tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The increased transcription of TNF-α and IL-6 was significantly attenuated (by 24.9 and 20.2%, respectively) by HsTX1[R14A] (100 nM). The concomitant increase in TNF-α and IL-6 release from BV-2 microglia was significantly attenuated by HsTX1[R14A] by 10.7 and 12.6%, respectively. In LPS-treated primary mouse microglia, the levels of TNF-α and nitric oxide were also attenuated by HsTX1[R14A] (26.1 and 20.4%, respectively). In an LPS-induced mouse model of neuroinflammation, both an immediate and delayed subcutaneous dose of HsTX1[R14A] (2 mg/kg) significantly reduced plasma and brain levels of the pro-inflammatory mediators TNF-α, IL-1ß and IL-6, with no impact on the anti-inflammatory IL-10. These results demonstrate that HsTX1[R14A] is a promising therapeutic candidate for the treatment of diseases with a neuroinflammatory component.


Assuntos
Canal de Potássio Kv1.3 , Lipopolissacarídeos , Animais , Citocinas/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , Doenças Neuroinflamatórias , Peptídeos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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