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Flavonoids, a commonly consumed natural product, elicit health-benefits such as antioxidant, anti-inflammatory, antiviral, anti-allergic, hepatoprotective, anti-carcinogenic and neuroprotective activities. Several studies have reported the beneficial role of flavonoids in improving memory, learning, and cognition in clinical settings. Their mechanism of action is mediated through the modulation of multiple signalling cascades. This polypharmacology makes them an attractive natural scaffold for designing and developing new effective therapeutics for complex neurological disorders like Alzheimer's disease and Parkinson's disease. Flavonoids are shown to inhibit crucial targets related to neurodegenerative disorders (NDDs), including acetylcholinesterase, butyrylcholinesterase, ß-secretase, γ-secretase, α-synuclein, Aß protein aggregation and neurofibrillary tangles formation. Conserved neuro-signalling pathways related to neurotransmitter biogenesis and inactivation, ease of genetic manipulation and tractability, cost-effectiveness, and their short lifespan make Caenorhabditis elegans one of the most frequently used models in neuroscience research and high-throughput drug screening for neurodegenerative disorders. Here, we critically appraise the neuroprotective activities of different flavonoids based on clinical trials and epidemiological data. This review provides critical insights into the absorption, metabolism, and tissue distribution of various classes of flavonoids, as well as detailed mechanisms of the observed neuroprotective activities at the molecular level, to rationalize the clinical data. We further extend the review to critically evaluate the scope of flavonoids in the disease management of neurodegenerative disorders and review the suitability of C. elegans as a model organism to study the neuroprotective efficacy of flavonoids and natural products.
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Flavonoides , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Flavonoides/química , Humanos , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Polifarmacologia , Disponibilidade BiológicaRESUMO
An overabundance of MCM7 protein, a component of the minichromosome maintenance complex that normally initiates DNA replication, has been reported to cause different types of cancers with aggressive malignancy. Inhibition of MCM7 may lead to a significant reduction in cancer-associated cell proliferation. Despite such significance of MCM7 in cancer, the protein structure is yet to be resolved experimentally. This significantly halts the structure-guided ligand designing for cancer therapy targeting the MCM7. The present study aims to resolve the tertiary structure of MCM7 and repurpose the FDA-approved clinically used drugs for cancer therapy by targeting MCM7 protein. The secondary and 3D structures of MCM7 were generated using multiple bioinformatics tools, including the Self-Optimized Prediction Method with Alignment (SOPMA), SWISS-MODEL, and I-TASSER. The reliability of the modeled structure was assessed using PROCHECK. Initially, a structure-guided virtual screening was performed on the approved drug library to identify potential hits against MCM7. The detailed molecular mechanism of receptor interactions of the identified hits was evaluated using extensive molecular dynamics simulation. The results from this study reveal an intriguing discovery of the potential of ergocalciferol (vitamin D2), cholecalciferol (vitamin D3), ergosterol (precursor of vitamin D2) and menaquinone (vitamin K2) as oncoprotein inhibitors for cancer therapy via inhibition of MCM7.
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INTRODUCTION: Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection resulting in COVID-19 disease is associated with widespread inflammation and a prothrombotic state, resulting in frequent venous thromboembolic (VTE) events. It is currently unknown whether anticoagulation is protective for VTE events. Therefore, we conducted a systematic review to identify predictors of VTE in COVID-19. METHODS: We searched PubMed, EMBASE, Google Scholar, and Ovid databases for relevant observational studies of VTE in COVID-19 disease. The effect size for predictors of VTE was calculated using a random-effects model and presented as forest plots. Heterogeneity among studies was expressed as Q statistics and I2. Bias was assessed using the Newcastle Ottawa Scale for all identified observational studies. Publication bias was assessed with funnel plot analysis. RESULTS: We identified 28 studies involving 6053 patients with suspected or confirmed COVID-19. The overall pooled prevalence of VTE events was 20.7%. Male sex was associated with a higher risk of VTE events, whereas prior history of VTE, smoking, and cancer were not. VTE events were significantly higher in severely ill patients, mechanically ventilated patients, those requiring intensive care admission, and those with a low PaO2/FiO2 ratio (P/F ratio). Chronic comorbidities, including cardiovascular disease, heart failure, renal disease, and pulmonary disease, did not increase the risk of VTE events. Patients with VTE had higher leukocyte counts and higher levels of D-dimer, C-reactive protein, and procalcitonin. The occurrence of VTE was associated with increased length of stay but did not impact mortality. Therapeutic and prophylactic doses of anticoagulation were not protective against VTE. CONCLUSION: VTE in COVID-19 is associated with male gender and severe disease but not with traditional risk factors for VTE. The occurrence of VTE does not appear to be mitigated by either prophylactic or therapeutic anticoagulation. The occurrence of VTE in this population is associated with an increased length of stay but does not appear to impact mortality.
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COVID-19 , Tromboembolia Venosa , Anticoagulantes/uso terapêutico , Coagulação Sanguínea , COVID-19/complicações , COVID-19/diagnóstico , Humanos , Masculino , SARS-CoV-2 , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologiaRESUMO
BACKGROUND: Clopidogrel is the most frequently used P2Y12 inhibitor as a component of the dual antiplatelet regimen in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). Prior studies have shown the variable efficacy of clopidogrel due to genotypic differences in the CYP2C19 enzyme function, which converts clopidogrel to its active metabolite. The aim of this meta-analysis is to evaluate the effectiveness of genotype testing-guided P2Y12 inhibitor prescription therapy to patients after PCI for ACS compared to non-genotype guided conventional treatment. METHODS: A comprehensive literature search was performed in PubMed, Embase, and Cochrane to identify relevant trials. Summary effects were calculated using a DerSimonian and Laird random-effects model as odds ratio with 95% confidence intervals for all the clinical endpoints. RESULTS: Seven studies with 9617 patients were included. Genotype-guided strategy arm included prasugrel or ticagrelor prescription to patients with loss of function (LOF) of CYP219 alleles (most commonly alleles being *2 and *3) and clopidogrel prescription to those without the LOF allele. The conventional arm included patients treated with clopidogrel without genotype testing. Comparison of genotype arm with conventional arm showed decreased major adverse cardiovascular events (MACE), improved cardiovascular (CV) mortality, and reduced incidence of myocardial infarction (MI) in the genotype arm, and a similar stroke incidence in the two arms. Regarding adverse events, the incidence of stent thrombosis was lower in the genotype arm than the conventional arm. CONCLUSION: Our analysis illustrates the possible advantages of genotype-guided P2Y12 inhibitor prescription strategy compared to non-genotype-guided strategy with reductions in MACE, CV mortality, MI, and stent thrombosis. This analysis can be used as a stepping stone to conducting further trials determining the efficacy of this treatment strategy in various ACS subtypes.
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Síndrome Coronariana Aguda , Infarto do Miocárdio , Intervenção Coronária Percutânea , Antagonistas do Receptor Purinérgico P2Y , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/terapia , Clopidogrel/uso terapêutico , Humanos , Infarto do Miocárdio/etiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Cloridrato de Prasugrel/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Ticagrelor/uso terapêutico , Resultado do TratamentoRESUMO
The polygenic nature of Alzheimer's disease (AD) and cross-talk between several signaling cascades make it harder to decode the disease pathogenesis. ß-secretase (BACE1) works upstream in the amyloidogenic processing of amyloid precursor protein (APP) to generate Aß that rapidly aggregates to form fibrils, the most abundant component of plaques observed in AD brains. Here, we report dual inhibition of BACE1 and Aß aggregation by neohesperidin, a flavonoid glycoconjugate, using multi-spectroscopic approaches, force microscopy, molecular modeling, and validated the potency in SH-SY5Y neuroblastoma cell lines. Steady-state and time-resolved fluorescence reveal that neohesperidin binds close to the catalytic aspartate dyad. This binding conformationally restricts the protein in closed form which possibly precludes APP recognition and thereby inhibits BACE1 activity. Neohesperidin also dose-dependently inhibits the amyloid fibril formation, as evident from ANS, ThT assay, and AFM. Neohesperidin ameliorates aggregated Aß25-35 induced ROS generation and mitochondrial dysfunction in the SH-SY5Y cell line. As a result, the amyloid induced apoptosis is significantly prohibited and normal neuronal morphology is rescued. These findings suggest neohesperidin as an inhibitor of the pathogenic conversion of Aß to fibrillar amyloid assembly. Neohesperidin thus emerges as a non-toxic multi-potent scaffold for the development of AD therapeutics.
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Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide , Ácido Aspártico Endopeptidases , Hesperidina/análogos & derivados , Fármacos Neuroprotetores , Fragmentos de Peptídeos , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular Tumoral , Hesperidina/química , Hesperidina/farmacologia , Humanos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismoRESUMO
Neural tube defects (NTDs), one of the most common birth defects, are strongly associated with the variations of several single nucleotide polymorphisms (SNPs) in the MTRR gene. The gene codes a key enzyme that is involved in the rejuvenation of methionine synthase activity. An allelic variant of the protein leads to missense mutation at 49th position from isoleucine to methionine (I49M) is associated with higher disease prevalence in different populations. Here, extensive molecular dynamics simulations and interaction network analysis reveal that the 49th isoleucine is a crucial residue that allosterically regulates the dynamics between the flavin mononucleotide (FMN) and NADP(H) binding domains. I49M variation alters the functional dynamics in a way that might impede the electron transport chain along the NADP(H) â flavin adenine dinucleotide â FMN pathway. The present study provides functional insights into the effect of the genetic variations of the MTRR gene on the NTDs disease pathogenesis.
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Ferredoxina-NADP Redutase/genética , Defeitos do Tubo Neural/patologia , Regulação Alostérica , Sítios de Ligação , Ferredoxina-NADP Redutase/classificação , Ferredoxina-NADP Redutase/metabolismo , Flavina-Adenina Dinucleotídeo/química , Flavina-Adenina Dinucleotídeo/metabolismo , Humanos , Simulação de Acoplamento Molecular , NADP/química , NADP/metabolismo , Defeitos do Tubo Neural/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Ligação ProteicaRESUMO
Introduction: Despite advances in surgical and anesthetic techniques, perioperative cardiovascular complications are a major cause of 30-day perioperative mortality. Major cardiovascular complications after noncardiac surgery include myocardial ischemia, congestive heart failure, arrhythmias, and cardiac arrest. Along with surgical risk assessment, perioperative medical optimization can reduce the rates and clinical impact of these complications.Areas Covered: In this review, the authors discuss the pharmacological basis, existing evidence, and professional society recommendations for drug management in preventing cardiovascular complications in patients undergoing noncardiac surgery.Expert opinion: Perioperative management of cardiovascular disease is an increasingly important and growing area of clinical practice. Societal guidelines regarding the use of most routine cardiovascular medications are based on a number of large clinical studies and provide a basic foundation to guide management. However, the heterogeneous nature of patients, as well as surgeries, makes it practically impossible to devise a 'one size fits all' recommendation in this setting. Thus, the importance of a more individualized approach to perioperative risk stratification and management is being increasingly recognized. The underlying comorbidities and cardiac profile as well as the risk of cardiac complications associated with the planned surgery must be factored in to understand the nuance of the management strategies.
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Doenças Cardiovasculares , Cardiopatias , Isquemia Miocárdica , Preparações Farmacêuticas , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Cardiopatias/etiologia , Cardiopatias/prevenção & controle , Humanos , Assistência Perioperatória , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controleRESUMO
BACKGROUND: Targeted therapies like vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) are the first-choice treatment in several types of cancers. We aim to determine the comparative risk of bleeding events associated with the VEGFR-TKIs through a network meta-analysis. METHODS: Published data search up to November 2018 reporting bleeding in cancer patients treated with VEGFR-TKIs was performed. The primary outcome was presence of hemorrhagic events at the end of the trial. Bleeding as a side-effect profile was examined for eleven VEGFR-TKIs (Apatinib, Brivanib, Cabozantinib, Lenvatinib, Motesanib, Nintedanib, Pazopanib, Regorafenib, Sorafenib, Sunitinib and Vandetanib). Network meta-analysis based on random effects model estimating Odds Ratio (OR) with 95 % confidence interval (CI), compared the risk of bleeding events among the VEGFR-TKIs with respect to placebo control conditions. RESULTS: Fifty Randomized Clinical Trials (RCTs) including 16,753 cancer patients were included in this analysis. Twenty studies compared VEGFR-TKIs with placebo, the remaining studies compared VEGFR-TKIs with the standard chemotherapeutic regimen. VEGFR-TKIs were associated with increased incidence of all-grade hemorrhagic events in comparison to control (standard chemotherapy and/or placebo) (OR = 1.79; 95 % CI 1.50-2.13, p-value <0.0001) and placebo (OR = 1.50; 95 % CI 1.16-1.93, p-value = 0.1). However, there was no difference in high-grade bleeding in patients treated with VEGFR-TKI in comparison to control (OR = 1.22; 95 % CI 0.87-1.71, p-value 0.74) or placebo alone (OR = 1.05; 95 % CI 0.65-1.70, p-value 0.73). Among individual VEGFR-TKIs, Sunitinib (OR = 3.31, 95 % CI 2.34-4.69) and Regorafenib (OR = 2.92, 95 % CI 1.50-5.71) were associated with higher risk of hemorrhagic events in comparison to placebo. CONCLUSION: VEGR-TKIs, particularly Sunitinib and Regorafenib appear to be associated with increased risk of bleeding incidence. TRIAL REGISTRATION NUMBER: PROSPERO CRD42017056406.
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Inibidores de Proteínas Quinases , Receptores de Fatores de Crescimento do Endotélio Vascular , Inibidores da Angiogênese , Humanos , Metanálise em Rede , Inibidores de Proteínas Quinases/efeitos adversos , Fatores de Crescimento do Endotélio VascularRESUMO
Cholesterol homeostasis results from a delicate interplay between influx and efflux of free cholesterol primarily mediated by ABCA1. Here we report downregulation of ABCA1 in hyper-cholesterol conditions in macrophages, which might be responsible for compromised reverse cholesterol transport and hyperlipidemia. Surprisingly, this is countered by the upregulation of a lesser known family member ABCA5 to maintain cholesterol efflux. The relative contribution of ABCA1 and ABCA5 toward cholesterol efflux was evaluated and revealed ABCA5 as the primary efflux mediator under high cholesterol load. These observations were correlated to cholesterol load in circulation in vivo, and we observed an inverse expression profile in mice models of atherosclerosis (ApoE-/-) and hyperlipidemia (PPARα-/-) in response to high cholesterol diet. Observations were further validated in human plasma samples. Simulation studies revealed a unique conformation of ABCA5 proposing a favored route for cholesterol loading onto high-density lipoproteins for reverse cholesterol transport. Thus, our study implicates a functional complementation between these two transporters, formulating an efficient strategy to maintain efflux in cholesterol excess conditions in macrophages.
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Transportador 1 de Cassete de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Colesterol/sangue , Dislipidemias/metabolismo , Transportador 1 de Cassete de Ligação de ATP/química , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adulto , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Dislipidemias/induzido quimicamente , Dislipidemias/genética , Feminino , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Moleculares , Conformação Proteica , Células RAW 264.7 , Células THP-1RESUMO
Acquired angioedema due to deficiency of C1 esterase inhibitor is also called acquired angioedema and is abbreviated as C1INH-AAE. It is a rare syndrome of recurrent episodes of angioedema, without urticaria, and in some patients, it is associated with B-cell lymphoproliferative disorders. Kidney involvement is rare in this condition. The monoclonal immunoglobulin secreted by a nonmalignant or premalignant B-cell or plasma cell clone, causing renal damage that represents a group of disorders which are termed as monoclonal gammopathy of renal significance (MGRS). In this article, we report a rare case of acquired C1 esterase deficiency angioedema and acute kidney injury with renal biopsy-proven MGRS. We present a 64-year-old Caucasian woman who presented with 2 weeks of recurring urticaria and new onset of acute kidney injury. She was diagnosed with monoclonal gammopathy-associated proliferative glomerulopathy through kidney biopsy, and serological workup came back positive for C1 esterase deficiency, implying acquired angioedema. Acquired angioedema is a rare disease with systemic involvement. Recurrent allergic manifestations and acute kidney injury should prompt MGRS as a differential.
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Angioedema/complicações , Angioedema/patologia , Gamopatia Monoclonal de Significância Indeterminada/complicações , Gamopatia Monoclonal de Significância Indeterminada/patologia , Linfócitos B/patologia , Biópsia , Proteína Inibidora do Complemento C1/imunologia , Feminino , Humanos , Rim/patologia , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Colonoscopy has been widely used as a diagnostic tool for many conditions, including inflammatory bowel disease and colorectal cancer. Colonoscopy complications include perforation, hemorrhage, abdominal pain, as well as anesthesia risk. Although rare, perforation is the most dangerous complication that occurs in the immediate post-colonoscopy period with an estimated risk of less than 0.1%. Studies on colonoscopy perforation risk between teaching hospitals and non-teaching hospitals are scarce. METHODS: The National Inpatient Sample database was queried for patients who underwent inpatient colonoscopy between January 2010 and December 2014 in teaching versus non-teaching facilities in order to study their perforation rates. Our study population included 257,006 patients. Univariate regression was performed, and the positive results were analyzed using a multivariate regression module. RESULTS: Teaching hospitals had a higher risk of perforation (odds ratio 1.23, confidence interval 1.07 - 1.42, P = 0.004). Perforation rates were higher in females, patients with inflammatory bowel disease and dilatation of strictures. Polypectomy did not yield any statistical difference between the study groups. Other factors such as African-American ethnicity appeared to have a lower risk. CONCLUSION: Perforation rates are higher in teaching hospitals. More studies are needed to examine the difference and how to mitigate the risks.
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INTRODUCTION: Although acute myocardial infarction (AMI) is a disease predominantly affecting adults >60â¯years of age, a significant proportion of the young population who have different risk profiles, are also affected. We undertook a retrospective analysis using National Inpatient Sample (NIS) 2010 to 2014 to evaluate gender differences in characteristics, treatments, and outcomes in the younger AMI population. METHODS: The NIS 2010-2014 was used to identify all patient hospitalizations with AMI between 18 to <45â¯years using ICD-9-CM codes. We demonstrated a gender-based difference of in-hospital all-cause mortality, other complications, and revascularization strategies in the overall AMI population and other subgroups of AMI [anterior wall ST-segment elevation MI (STEMI), and non-anterior wall STEMI and non-STEMI (NSTEMI)]. RESULTS: A total of 156,018 weighted records of AMI hospitalizations were identified, of which 111,894 were men and 44,124 were women. Young women had a higher prevalence of anemia, chronic lung disease, obesity, peripheral vascular disease, and diabetes. Conversely, young men had a higher prevalence of dyslipidemia, smoking, and alcohol. Among non-traditional risk factors, women had a higher prevalence of depression and rheumatologic/collagen vascular disease. There was no difference in all-cause in-hospital mortality in women compared to men [2.03% vs 1.48%; OR 1.04, CI (0.84-1.29); Pâ¯=â¯.68], including in subgroup analysis of NSTEMI, anterior wall STEMI, and non-anterior wall STEMI. Women with AMI were less likely to undergo percutaneous coronary intervention [47.13% vs 61.17%; OR 0.66, 95% CI (0.62-0.70; Pâ¯<â¯.001] and coronary artery bypass grafting [5.6% vs 6.0%; OR 0.73, 95% CI 0.64-0.83; Pâ¯<â¯.001] compared to men. Women were also less likely to undergo percutaneous coronary intervention within 24â¯h of presentation (38.47% vs 51.42%, Pâ¯<â¯.001). CONCLUSION: Despite higher baseline comorbidities in young women with AMI, there was no difference in in-hospital mortality in women compared to men. Additional studies are needed to evaluate the impact of gender on clinical presentation, treatment patterns, and outcomes of AMI in young patients.
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Eletrocardiografia/métodos , Hospitalização/estatística & dados numéricos , Transtornos Mentais , Infarto do Miocárdio , Revascularização Miocárdica , Doenças não Transmissíveis , Adulto , Fatores Etários , Comorbidade , Angiografia Coronária/métodos , Angiografia Coronária/estatística & dados numéricos , Feminino , Mortalidade Hospitalar , Humanos , Classificação Internacional de Doenças , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Revascularização Miocárdica/métodos , Revascularização Miocárdica/estatística & dados numéricos , Doenças não Transmissíveis/classificação , Doenças não Transmissíveis/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Prevalência , Fatores Sexuais , Estados Unidos/epidemiologiaRESUMO
OBJECTIVE: To explore the association of peripheral neuropathy with vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) use in patients with cancer. METHODS: Published data search up to November 2018 reporting peripheral neuropathy in patients with cancer treated with VEGFR-TKIs was performed. The primary outcome was presence of peripheral neuropathy at the end of the trial. Random-effects meta-analysis was performed to estimate relative risk (RR) of individual treatment. RESULTS: Thirty randomized clinical trials (RCTs) including 12,490 patients with cancer were included in this analysis. Eight studies compared VEGFR-TKIs with placebo and the remaining studies compared VEGFR-TKIs with the standard chemotherapeutic regimen. When compared against placebo, VEGFR-TKIs were associated with a higher risk of peripheral neuropathy (RR 1.76; 95% confidence interval [CI] 1.13-2.75, p = 0.01). Similarly, a stronger association was noted for sensory neuropathy with VEGFR-TKIs monotherapy (RR 1.61; 95% CI 1.09-2.37, p = 0.02). Risk of peripheral neuropathy with VEGFR-TKIs was higher even when they were compared against control (either placebo or standard chemotherapeutic agents) (RR 1.08; 95% CI 1.01-1.15, p = 0.03). High-grade neuropathy (RR 1.28; 95% CI 1.06-1.54, p <0.01) and high-grade sensory neuropathy (RR 1.38; 95% CI 1.09-1.74, p < 0.01) were noted more frequently with VEGFR-TKIs treatment compared against control. CONCLUSIONS: VEGFR-TKIs therapy appeared to be associated with an increased risk of neuropathy.
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Neoplasias/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/epidemiologia , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , HumanosRESUMO
Epithelial to mesenchymal transition (EMT) is compulsory for metastatic dissemination and is stimulated by TGF-ß. Although targeting EMT has significant therapeutic potential, very few pharmacological agents have been shown to exert anti-metastatic effects. BI-69A11, a competitive Akt inhibitor, displays anti-tumor activity toward melanoma and colon carcinoma. This study provides molecular and biochemical insights into the effects of BI-69A11 on EMT in colon carcinoma cells in vitro and in vivo. BI-69A11 inhibited metastasis-associated cellular migration, invasion and adhesion by inhibiting the Akt-ß-catenin pathway. The underlying mechanism of BI-69A11-mediated inhibition of EMT included suppression of nuclear transport of ß-catenin and diminished phosphorylation of ß-catenin, which was accompanied by enhanced E-cadherin-ß-catenin complex formation at the plasma membrane. Additionally, BI-69A11 caused increased accumulation of vinculin in the plasma membrane, which fortified focal adhesion junctions leading to inhibition of metastasis. BI-69A11 downregulated activation of the TGF-ß-induced non-canonical Akt/NF-κB pathway and blocked TGF-ß-induced enhanced expression of Snail causing restoration of E-cadherin. Overall, this study enhances our understanding of the molecular mechanism of BI-69A11-induced reversal of EMT in colorectal carcinoma cells in vitro, in vivo and in TGF-ß-induced model systems.
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Antígenos CD/metabolismo , Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Caderinas/metabolismo , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Quinolonas/farmacologia , beta Catenina/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Humanos , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo , Vinculina/metabolismoRESUMO
G-quadruplex (G4) structures are known to be promising anticancer drug targets and flavonols (an important class of flavonoids) are small molecules reported to possess several health-promoting properties including those of anticancer activities. In this work, we explored the interactions of the structurally related plant flavonols kaempferol (KAE; 3,5,7,4'OH flavone) and morin (MOR; 3,5,7,2',4'OH flavone) with various G4-DNA sequences along with duplex DNA using a combination of spectroscopic and molecular docking studies. Our results revealed that KAE shows preferential interaction with VEGF G4-DNA in comparison to the other G4 sequences and duplex DNA. Moreover, KAE enhances the thermal stability of VEGF G4-DNA. In contrast, MOR exhibits an appreciably weaker level of interaction with both duplex and various G4-DNAs, with no significant structural specificity. The contrasting DNA binding behaviors suggest a crucial role of the 2'OH substituent in the B-ring of flavonol moiety. While KAE is relatively planar, MOR adopts a significantly non-planar conformation attributable to steric hindrance from the additional 2'OH substituent. This small structural difference is apparently very important for the ability of KAE and MOR to interact with VEGF G4-DNA. Thus, KAE (but not MOR) appears to be an effective ligand for VEGF G4-DNA, opening up possibilities of its application for regulation of gene expression in cancer cells.
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DNA/metabolismo , Flavonóis/química , Flavonóis/metabolismo , Quadruplex G , Radical Hidroxila/química , Simulação de Acoplamento Molecular , Fator A de Crescimento do Endotélio Vascular/genética , DNA/química , Flavonoides/química , Flavonoides/metabolismo , Quempferóis/química , Quempferóis/metabolismo , Análise Espectral , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
VGF (non-acronymic)is a secreted chromogranin/secretogranin that gives rise to a number of bioactive peptides by a complex proteolysis mechanism. VGF-derived peptides exert an extensive array of biological effects in energy metabolism, mood regulation, pain, gastric secretion function, reproduction and, perhaps, cancer. It is therefore surprising that very little is known about receptors and binding partners of VGF-derived peptides and their downstream molecular mechanisms of action. Here, using affinity chromatography and mass spectrometry-based protein identification, we have identified the heat shock cognate 71 kDa protein A8 (HSPA8)as a binding partner of human TLQP-21 on the surface of human neuroblastomaSH-SY5Y cells. Binding of TLQP-21 to membrane associated HSPA8 in live SH-SY5Y cells was further supported by cross-linking to live cells. Interaction between HSPA8 and TLQP-21 was confirmed in vitro by label-free Dynamic Mass Redistribution (DMR) studies. Furthermore, molecular modeling studies show that TLQP-21 can be docked into the HSPA8 peptide binding pocket. Identification of HSPA8 as a cell surface binding partner of TLQP-21 opens new avenues to explore the molecular mechanisms of its physiological actions, and of pharmacological modulation thereof.
Assuntos
Proteínas de Choque Térmico HSC70/metabolismo , Neuropeptídeos/química , Fragmentos de Peptídeos/metabolismo , Biotinilação , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proteínas de Choque Térmico HSC70/química , Humanos , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/química , Ligação Proteica , Conformação Proteica , Propriedades de SuperfícieRESUMO
Functional perturbation of mitochondria is associated with fulminant hepatic failure (FHF). d-Galactosamine/lipopolysaccharide (d-GalN/LPS)-induced FHF is a renowned model to evaluate the efficacy of hepatoprotective agents. Lycopene is an antioxidant and phytonutrient from the carotenoid family. The health benefits of lycopene are prominent against cancer and cardiovascular, lung, liver, and skin problems. Recent studies have demonstrated the hepatoprotective, antidyslipidemic, and antioxidant roles of lycopene. The current study was designed to appraise the ability of lycopene to prevent mitochondrial dysfunction during the d-GalN/LPS-induced FHF. The administration of d-GalN/LPS (300 mg and 30 µg/kg body weight, respectively) to the experimental rats induced several disturbances in mitochondrial function. The lipid peroxide and hydrogen peroxide levels were increased (p < 0.05). The activities of mitochondrial antioxidants, tricarboxylic acid (TCA) cycle, and electron transport chain enzymes and the cellular adenosine triphosphate (ATP) content were decreased (p < 0.05). Lycopene (10 mg/kg body weight for 6 days) pretreatment attenuated lipid peroxidation and prohibited the excessive synthesis of hydrogen peroxide. The d-GalN/LPS-induced impairment in ATP production and increased enzyme activities were effectively prevented by the lycopene administration. The lycopene-mediated mitochondrial protection was mainly ascribed to the strong antioxidant potential of this phytonutrient. Molecular modeling results obtained show evidence that lycopene inhibits several lipoxygenases and provides rationale for the observed prevention of lipid peroxidation in the mitochondrial membrane. The carotenoid lycopene combatted oxidative stress, scavenged free radicals, prevented ROS generation, and inhibited the toxic effects of d-GalN/LPS during FHF.
Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Inibidores de Lipoxigenase/farmacologia , Lipoxigenases/metabolismo , Falência Hepática Aguda/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Trifosfato de Adenosina/agonistas , Trifosfato de Adenosina/antagonistas & inibidores , Trifosfato de Adenosina/biossíntese , Animais , Antioxidantes/química , Sítios de Ligação , Carotenoides/química , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Ciclo do Ácido Cítrico/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/agonistas , Complexo de Proteínas da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Galactosamina/toxicidade , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Inibidores de Lipoxigenase/química , Lipoxigenases/química , Fígado , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Licopeno , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Simulação de Acoplamento Molecular , Estresse Oxidativo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Ratos , Ratos WistarRESUMO
Aniline, heterocyclic aromatic amines, and arylamines are known carcinogens. Recently aniline mustard has come into prominence as a novel anticancer agent. In this project, microwave irradiation has been used to synthesize an optically active alkylated aniline namely 2,6-dimethyl-4-(1-(p-tolyl)ethyl)aniline (abbreviated DMPA). The presence of quartet and doublet peaks in NMR and a single chromatogram in HPLC verified that the final product DMPA, prepared from the synthesis reactions, had no major impurities. By using a Lux chiral column in HPLC, two peaks have been detected in the chromatogram, which correspond to two enantiomers of the chiral aniline derivative. Fluorescence spectroscopic measurements on DMPA indicated conspicuous dependence of its emission behavior on the polarity (in terms of the empirical polarity parameter ET(30)) of the homogeneous solvents used, a property important for an optical sensor. The nature of the emission profiles, along with the relevant parameter namely wavelength at emission maximum (λemmax) is used to infer the distribution, binding and microenvironment of the DMPA molecules in human serum albumin protein (HSA). DMPA is weakly fluorescent in aqueous buffer medium, with a dramatic enhancement in the fluorescence emission in the presence of HSA. Molecular modeling studies have been carried out on the two enantiomers (R and S) of DMPA with HSA. The implications of these findings are examined in relation to the potentialities of DMPA as a novel fluorescence sensor for biological systems.