RESUMO
Both infection and autoimmune disease can disrupt pre-existing Ab titers leading to diminished serological memory, yet the underlying mechanisms are not well understood. In this article, we report that TNF-α, an inflammatory cytokine, is a master regulator of the plasma cell (PC) niche in the bone marrow (BM). Acute rTNF-α treatment depletes previously existing Ab titers after vaccination by limiting PC occupancy or retention in the BM. Consistent with this phenomenon, mice lacking TNF-α signaling have elevated PC capacity in the BM and higher Ab titers. Using BM chimeric mice, we found that PC egress from the BM is regulated in a cell-extrinsic manner, by radiation-resistant cells via TNF-α receptor 1 signaling, leading to increased vascular permeability and CD138 downregulation on PCs. PC motility and egress in the BM are triggered within 6 h of recombinant TNF-α treatment. In addition to promoting egress, TNF-α signaling also prevented re-engraftment into the BM, leading to reduced PC survival. Although other inflammatory stimuli can promote PC egress, TNF-α signaling is necessary for limiting the PC capacity in the BM. Collectively, these data characterize how TNF-α-mediated inflammation attenuates the durability of serological memory and shapes the overall size and composition of the Ab-secreting cell pool in the BM.
Assuntos
Medula Óssea , Fator de Necrose Tumoral alfa , Camundongos , Animais , Plasmócitos , Transdução de Sinais , Células da Medula Óssea , Fatores ImunológicosRESUMO
Understanding mortality causes is important for the conservation of endangered species, especially in small and isolated populations inhabiting anthropized landscapes where both natural and human-caused mortality may hinder the conservation of these species. We investigated the mortality causes of 53 free-ranging brown bears (Ursus arctos) found dead between 1998 and 2023 in the Cantabrian Mountains (northwestern Spain), a highly human-modified region where bears are currently recovering after being critically threatened in the last century. We detected natural traumatic injuries in 52.63% and infectious diseases in 39.47% of the 38 bears for which the mortality causes were registered, with 21.05% of these cases presenting signs of both infectious diseases and traumas. More specifically, almost 30% of the bears died during or after intraspecific fights, including sexually selected infanticide (10.53%). In addition, primary infectious diseases such as infectious canine hepatitis, distemper, clostridiosis and colibacillosis caused the death of 15.79% of the bears. The number of direct human-caused deaths (i.e., shooting, poisoning, snare) decreased over the study period. This study also reveals three new mortality causes triggered by pathogens, two of which-Clostridium novyi and verotoxigenic Escherichia coli-not previously described in ursids, and the other one, canine distemper virus, never reported in brown bears as cause of death. New management strategies for the conservation of Cantabrian bears, which are urgently needed due to the rapid expansion of the population, should consider the mortality causes described in this study and must promote further research to elucidate how the high prevalence of infectious diseases may threaten the current recovery of the population.
Assuntos
Doenças Transmissíveis , Ursidae , Humanos , Animais , Doenças Transmissíveis/veterinária , Espanha/epidemiologiaRESUMO
Neoponcirin causes anxiolytic-like effects in mice when administered intraperitoneally but not orally. Neoponcirin is non-water-soluble and insoluble in solvents, and in medium acid, it isomerizes, reducing its bioavailability. To improve the pharmacological properties of neoponcirin, we formed a neoponcirin complex with beta-cyclodextrin (NEO/ßCD), which was characterized by FT-IR, UV-Vis, and NMR, and their solubility profile. We evaluated the antidepressant-like effects of NEO/ßCD acutely administered to mice orally in the behavioral paradigms, the tail suspension (TST) and the forced swimming (FST) tests. We also analyzed the benefits of repeated oral doses of NEO/ßCD on depression- and anxiety-like behaviors induced in mice by chronic unpredictable mild stress (CUMS), using the FST, hole board, and open field tests. We determined the stressed mice's expression of stress-related inflammatory cytokines (IL-1ß, IL-6, and TNFα) and corticosterone. Results showed that a single or chronic oral administration of NEO/ßCD caused a robust antidepressant-like effect without affecting the ambulatory activity. In mice under CUMS, NEO/ßCD also produced anxiolytic-like effects and avoided increased corticosterone and IL-1ß levels. The effects of the NEO/ßCD complex were robust in both the acute and the stress chronic models, improving brain neurochemistry and recovering immune responses previously affected by prolonged stress.
Assuntos
Antidepressivos , Depressão , Estresse Psicológico , beta-Ciclodextrinas , Animais , beta-Ciclodextrinas/farmacologia , beta-Ciclodextrinas/química , Camundongos , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Masculino , Estresse Psicológico/tratamento farmacológico , Depressão/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Ansiedade/tratamento farmacológico , Ansiolíticos/farmacologia , Natação , Administração OralRESUMO
MicroRNAs (miRNAs) represent a class of small noncoding RNAs that are considered a novel emerging class of disease biomarkers in a variety of afflictions. Sensitive detection of miRNA is typically achieved using hybridization-based methods coupled with genetic amplification techniques. Although their sensitivity has improved, amplification techniques often present erroneous results due to their complexity. In addition, the use of these techniques is usually linked to the application of protein enzymes, the activity of which is dependent on the temperature and pH of the medium. To address these drawbacks, an alternative genetic enzyme for the highly sensitive detection of miRNAs is proposed in this work. Multicomponent nucleic acid enzymes (MNAzymes), coupled with the use of DNA-functionalized gold nanoparticles (AuNPs), were used in this study to develop an isothermal signal amplification strategy for visual genetic detection. miR146a, a biomarker of bovine mastitis present in milk, was selected as a model analyte. The developed methodology is easily carried out in 80 min at 50 °C, generating a low visual limit of detection of 250 pM based on the observation of a color change. The methodology was successfully applied to the detection of miR146a in raw cow milk samples.
Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Ácidos Nucleicos , Animais , Bovinos , Feminino , MicroRNAs/genética , Ouro , Técnicas Biossensoriais/métodosRESUMO
We conduct a sectoral analysis of electricity consumption during the Coronavirus disease 2019 (COVID-19) pandemic for the primary sectors that make up Colombia's unregulated and regulated markets. Applying a model of seemingly unrelated regression equations to examine data between February 2015 and May 2021, we evidence the recomposition of electricity consumption related to mandatory preventive isolation during the pandemic. Average consumption in the residential sector increased by 16.9% as working from home became prevalent. In contrast, unregulated market sectors subjected to quarantines presented a significant decrease in consumption, up to 32% in the financial sector. While industries that were not subjected to mandatory confinement, such as health, food (agriculture), and water supply, had no significant effect. Our results are relevant for informing demand forecasts and planning network expansions to guarantee the reliability of the supply as pandemic practices such as working from home become permanent.
RESUMO
Cancer is a relevant health problem worldwide. In 2020, leukemias represented the 13th most commonly reported cancer cases worldwide but the 10th most likely to cause deaths. There has been a progressive increase in the efficacy of treatments for leukemias; however, these still generate important side effects, so it is imperative to search for new alternatives. Defensins are a group of antimicrobial peptides with activity against cancer cells. However, the cytotoxic mechanism of these peptides has been described mainly for animal defensins. This study shows that defensin γ-thionin (Capsicum chinense) is cytotoxic to the K562 leukemia cells with an IC50 = 290 µg/mL (50.26 µM) but not for human peripheral blood mononuclear cells. Results showed that γ-thionin did not affect the membrane potential; however, the peptide modified the mitochondrial membrane potential (ΔΨm) and the intracellular calcium release. In addition, γ-thionin induced apoptosis in K562 cells, but the activation of caspases 8 and 9 was not detected. Moreover, the activation of calpains was detected at one hour of treatment, suggesting that γ-thionin activates the caspase-independent apoptosis. Furthermore, the γ-thionin induced epigenetic modifications on histone 3 in K562 cells, increased global acetylation (~2-fold), and specific acetylation marks at lysine 9 (H3K9Ac) (~1.5-fold). In addition, γ-thionin increased the lysine 9 methylation (H3K9me) and dimethylation marks (H3K9me2) (~2-fold), as well as the trimethylation mark (H3K9me3) (~2-fold). To our knowledge, this is the first report of a defensin that triggers caspase-independent apoptosis in cancer cells via calpains and regulating chromatin remodelation, a novel property for a plant defensin.
Assuntos
Antineoplásicos , Capsicum , Leucemia Mielogênica Crônica BCR-ABL Positiva , Tioninas , Animais , Humanos , Tioninas/farmacologia , Células K562 , Capsicum/química , Peptídeos Antimicrobianos , Chile , Leucócitos Mononucleares/metabolismo , Lisina/farmacologia , Apoptose , Peptídeos/farmacologia , Antineoplásicos/farmacologia , Caspases/metabolismo , Defensinas/farmacologia , Epigênese GenéticaRESUMO
Microtubule targeting agents (MTA) are anti-cancer molecules that bind tubulin and interfere with the microtubule functions, eventually leading to cell death. In the present study, we used an in vitro microtubule polymerization assay to screen several venom families for the presence of anti-microtubule activity. We isolated myotoxin-3, a peptide of the crotamine family, and three isoforms from the venom of the Northern Pacific rattlesnake Crotalus oreganus oreganus, which was able to increase tubulin polymerization. Myotoxin-3 turned out to be a cell-penetrating peptide that slightly diminished the viability of U87 glioblastoma and MCF7 breast carcinoma cells. Myotoxin 3 also induced remodeling of the U87 microtubule network and decreased MCF-7 microtubule dynamic instability. These effects are likely due to direct interaction with tubulin. Indeed, we showed that myotoxin-3 binds to tubulin heterodimer with a Kd of 5.3 µM and stoichiometry of two molecules of peptide per tubulin dimer. Our results demonstrate that exogenous peptides are good candidates for developing new MTA and highlight the richness of venoms as a source of pharmacologically active molecules.
Assuntos
Venenos de Crotalídeos , Neurotoxinas , Animais , Humanos , Neurotoxinas/metabolismo , Tubulina (Proteína)/metabolismo , Crotalus/metabolismo , Venenos de Crotalídeos/farmacologia , Venenos de Crotalídeos/metabolismo , Peptídeos/farmacologia , Peptídeos/metabolismoRESUMO
Glioblastoma is the most aggressive and invasive form of central nervous system tumors due to the complexity of the intracellular mechanisms and molecular alterations involved in its progression. Unfortunately, current therapies are unable to stop its neoplastic development. In this context, we previously identified and characterized AaTs-1, a tetrapeptide (IWKS) from Androctonus autralis scorpion venom, which displayed an anti-proliferative effect against U87 cells with an IC50 value of 0.57 mM. This peptide affects the MAPK pathway, enhancing the expression of p53 and altering the cytosolic calcium concentration balance, likely via FPRL-1 receptor modulation. In this work, we designed and synthesized new dendrimers multi-branched molecules based on the sequence of AaTs-1 and showed that the di-branched (AaTs-1-2B), tetra-branched (AaTs-1-4B) and octo-branched (AaTs-1-8B) dendrimers displayed 10- to 25-fold higher effects on the proliferation of U87 cells than AaTs-1. We also found that the effects of the newly designed molecules are mediated by the enhancement of the ERK1/2 and AKT phosphorylated forms and by the increase in p53 expression. Unlike AaTs-1, AaTs-1-8B and especially AaTs-1-4B affected the migration of the U87 cells. Thus, the multi-branched peptide synthesis strategy allowed us to make molecules more active than the linear peptide against the proliferation of U87 glioblastoma cells.
Assuntos
Antineoplásicos/farmacologia , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Oligopeptídeos/farmacologia , Venenos de Escorpião/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dendrímeros/química , Dendrímeros/farmacologia , Humanos , Oligopeptídeos/química , Venenos de Escorpião/química , EscorpiõesRESUMO
RegulonDB, first published 20 years ago, is a comprehensive electronic resource about regulation of transcription initiation of Escherichia coli K-12 with decades of knowledge from classic molecular biology experiments, and recently also from high-throughput genomic methodologies. We curated the literature to keep RegulonDB up to date, and initiated curation of ChIP and gSELEX experiments. We estimate that current knowledge describes between 10% and 30% of the expected total number of transcription factor- gene regulatory interactions in E. coli. RegulonDB provides datasets for interactions for which there is no evidence that they affect expression, as well as expression datasets. We developed a proof of concept pipeline to merge binding and expression evidence to identify regulatory interactions. These datasets can be visualized in the RegulonDB JBrowse. We developed the Microbial Conditions Ontology with a controlled vocabulary for the minimal properties to reproduce an experiment, which contributes to integrate data from high throughput and classic literature. At a higher level of integration, we report Genetic Sensory-Response Units for 200 transcription factors, including their regulation at the metabolic level, and include summaries for 70 of them. Finally, we summarize our research with Natural language processing strategies to enhance our biocuration work.
Assuntos
Biologia Computacional/métodos , Escherichia coli K12/genética , Regulação Bacteriana da Expressão Gênica , Genômica , Ontologia Genética , Redes Reguladoras de Genes , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
Cases of West Nile neuroinvasive disease (WNND) in Spain increased in summer 2020. Here we report on this increase and the local, regional and national public health measures taken in response. We analysed data from regional surveillance networks and the National Epidemiological Surveillance Network, both for human and animal West Nile virus (WNV) infection. During the 2020 season, a total of 77 human cases of WNV infection (median age 65 years; 60% males) were detected in the south-west of Spain; 72 (94%) of these cases developed WNND, presenting as meningoencephalitis, seven of which were fatal. In the previous two decades, only six human cases of WNND were detected in Spain. Reduced activities for vector control this season, together with other factors, might have contributed to the massive increase. Public health measures including vector control, campaigns to raise awareness among physicians and the general population, and interventions to ensure the safety of donations of blood products, organs, cells and tissues were effective to reduce transmission. Going forward, maintenance of vector control activities and an update of the vector-borne diseases response plan in Spain is needed.
Assuntos
Meningoencefalite , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Idoso , Animais , Feminino , Humanos , Masculino , Estações do Ano , Espanha/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/prevenção & controleRESUMO
Avocado (Persea americana Mill.) is a tree native from central and eastern México that belongs to the Lauraceae family. Avocado has three botanical varieties known as Mexican (P. americana var. drymifolia), West Indian (P. americana var. americana), and Guatemalan (P. americana var. guatemalensis). It is an oil-rich fruit appreciated worldwide because of its nutritional value and the content of bioactive molecules. Several avocado molecules show attractive activities of interest in medicine. Avocado fatty acids have beneficial effects on cardiovascular disease risk factors. Besides, this fruit possesses a high content of carotenoids and phenolic compounds with possible antifungal, anti-cancer and antioxidant activities. Moreover, several metabolites have been reported with anti-inflammatory effects. Also, an unsaponifiable fraction of avocado in combination with soybean oil is used for the treatment of osteoarthritis. The Mexican variety is native from México and is characterized by the anise aroma in leaves and by small thin-skinned fruits of rich flavor and excellent quality. However, the study of the bioactive molecules of the fruit has not been addressed in detail. In this work, we achieved a literature review on the inflammatory, immunomodulatory and cytotoxic properties of long-chain fatty acids and derivatives from Mexican avocado seed. Also, the antioxidant and anti-inflammatory properties of the oil extracted from the avocado seed are referred. Finally, the antimicrobial, immunomodulatory, and cytotoxic activities of some antimicrobial peptides expressed in the fruit are reviewed.
Assuntos
Anti-Infecciosos , Persea , Anti-Infecciosos/farmacologia , Frutas , México , SementesRESUMO
Prostate cancer is the most highly diagnosed cancer in men worldwide. It is characterized by high proliferation, great invasion and metastatic potential. Sodium channel subtypes have been identified as highly expressed in different prostate cancer cell lines. In this study, we have screened the negatively charged fractions of Androctonus australis (Aa) scorpion venom to identify active peptides on DU145 prostate cancer cells proliferation. The most active compound was identified to be the sodium channel peptide AaHIV with an IC50 value of 15⯵M. At this concentration, AaHIV had low effect on the adhesion of DU145â¯cells to fibronectin. When compared to other Na+ channel Aa toxins, AaHIV was found to be 2 times more active than AaHI and AaHII on DU145â¯cells proliferation and slightly less active than AaHII on their adhesion. The three peptides are inactive on DU145â¯cells migration. AaHIV was found to be 16 times more active than veratridine, asteroidal alkaloid from plants of the lily family widely used as a sodium channel activator. Electrophysiological experiments showed that the AaHIV toxin activates Nav1.6 channel, suggesting that this sodium channel subtype is implicated in the proliferation of DU145 prostate cancer cells.
Assuntos
Neoplasias da Próstata/patologia , Venenos de Escorpião/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Canal de Sódio Disparado por Voltagem NAV1.6/efeitos dos fármacos , Canal de Sódio Disparado por Voltagem NAV1.6/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Escorpiões , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/metabolismoRESUMO
Gold nanoparticles of different sizes have been synthesized and surface-functionalized with selected RNA probes in order to develop a rapid, low-cost and sensitive method for detection of microRNA146a (miR146a). The strategy is based on the change of colour that can be observed visually after aggregation of the RNA modified-gold nanoparticles (AuNPs) in presence of miR146a. Experimental conditions have been carefully selected in order to obtain a good sensitivity that allows to perform visual detection of microRNA at the nM level, achieving a detection limit of 5 nM. Good repeatability and selectivity versus other sequences that only differ from miR146a in 3 bases was achieved. miR146a has been described as one of the main microRNA involved in the immune response of bovine mastitis, being expressed in tissue, blood and milk samples. The method was successfully applied to the detection of miR146a in raw cow milk samples. The present scheme constitutes a rapid and low-cost alternative to perform highly sensitive detection of microRNA without the need of instrumentation and amplification steps for the early detection of bovine mastitis in the agrofood industry. Graphical abstract Schematic representation of the assay based on aggregation of RNA-modified gold nanoparticles (blue) in presence of microRNA146a generating a dark blue spot onto a solid support, versus a pink spot observed in absence of miR146a due to dispersed gold nanoparticles (red).
Assuntos
Técnicas Biossensoriais/métodos , Colorimetria/métodos , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Animais , Bovinos , Limite de Detecção , Leite/químicaRESUMO
OBJECTIVES: The aims of this study were to compare learned helplessness (LH) and perceived self-efficacy (SE) in patients with fibromyalgia (FM) and rheumatoid arthritis (RA) and to assess their correlation with functional disability, level of perceived pain, and fatigue. METHODS: This multicenter, cross-sectional study included consecutive patients (aged ≥18 years) with RA, according to the 2010 American College of Rheumatology/European League Against Rheumatism criteria, and FM, according to 2010 American College of Rheumatology criteria. Learned helplessness was measured by the Rheumatology Attitude Index, Spanish version; SE with the Arthritis Self-efficacy Scale, Spanish version; functional capacity with the Health Assessment Questionnaire (HAQ), Argentine version; depression with Center for Epidemiological Studies-Depression Scale 7-item version and perceived pain and fatigue by the visual analog scale. Disease activity was measured by the Clinical Disease Activity Index (CDAI) and disease impact with the Fibromyalgia Impact Questionnaire (FIQ). RESULTS: A total of 215 patients, 100 with FM and 115 with RA, were included. Mean age was 59 (SD, 14) years and 58 (SD, 13) years for FM and RA, patients respectively. Whereas LH and depression were significantly higher, SE was significantly lower in FM patients. We found a positive correlation between LH and HAQ, pain, depression, fatigue, FIQ, and CDAI in FM and RA patients. We observed a negative correlation between SE and HAQ, pain, depression, fatigue, FIQ (FM), and CDAI (RA) in both groups. CONCLUSIONS: Both LH and SE correlate significantly with functional capacity, perceived pain, disease activity, and disease impact in RA and FM patients. Learned helplessness was higher in patients with active disease or high disease impact, as opposed to those in remission or with low disease impact, and the reverse was true for SE. Patients with FM had significantly more LH, pain, fatigue, and depression and less SE compared with those with RA.
Assuntos
Artrite Reumatoide/psicologia , Fibromialgia/psicologia , Desamparo Aprendido , Autoeficácia , Adulto , Idoso , Artrite Reumatoide/complicações , Artrite Reumatoide/fisiopatologia , Estudos Transversais , Fadiga/etiologia , Fadiga/fisiopatologia , Fadiga/psicologia , Feminino , Fibromialgia/complicações , Fibromialgia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Dor/fisiopatologia , Dor/psicologia , Inquéritos e QuestionáriosRESUMO
Background and objectives: Dipeptidyl-Peptidase 4 (DPP-4) is a protein expressed in numerous cells and tissues. Recently it has shown its involvement as a catalyst in the inflammatory response in various pulmonary, autoimmune, intestinal and other pathologies. The objective of this study was to compare the preoperative serum levels of DPP-4 in patients with and without surgical finding of perivesicular inflammation. Materials and methods: a cross-sectional analytical study nested in a prospective cohort, including patients scheduled for elective cholecystectomy, without surgical complications, that were 18-70 years of age, with low cardiovascular risk, without a history of peritonitis, pancreatitis, or jaundice and underwent ERCP protocol, type 2 diabetes mellitus, acute inflammatory (Protein C Reactive < 3 mg/L, leucocytes < 10 1000/mm3), neoplastic, nephrologic or liver disease, the use of anti-inflammatory drugs, steroids and/or antibiotics, the use of pacemakers or metallic implants and without major amputations and whom agreed to participate by providing their informed consent. Ethical and Research register: 45-16. Prior to surgery we compiled anthropometric data and a blood sample to determine the serum levels of DPP-4. The presence of perivesicular inflammation was determined in the surgery. The data was analyzed using the statistical program Rstudio. Results: High BMI values were observed (27.8 ± 6.4); waist circumference (94.7 ± 15.1) and percentage of fat mass (34.7 ± 11.7), showing a cumulative frequency of 65.9% for overweight/obesity. In 27.3% of the interventions, intraoperative perivesicular inflammation findings were reported. The serum levels of DPP-4 were lower in the group of patients with perivesicular inflammation (3947.6 ± 1659.5 vs. 3053.2 ± 1469.6, LC95% of the difference: 160.4-1628.3), being statistically significant (P = 0.018). Conclusions: In the subacute or chronic phases of cholecystitis, there appears to be a constant consumption of DPP-4, which would modulate a better immune response that could be related to the reduction of postoperative complications, so the use of Serum levels of DPP-4 as an early biomarker could improve the diagnostic accuracy of this pathology and the surgical approach.
Assuntos
Colecistectomia/métodos , Dipeptidil Peptidase 4/análise , Inflamação/sangue , Adolescente , Adulto , Idoso , Biomarcadores/análise , Biomarcadores/sangue , Colecistectomia/tendências , Doença Crônica , Estudos de Coortes , Estudos Transversais , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Dipeptidil Peptidase 4/sangue , Feminino , Humanos , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Integrins are a large family of cell surface receptors mediating the interaction of cells with their microenvironment and they play an important role in glioma biology. In the present work, we reported the anti-tumor effect of Sm-PLGV a phospholipase A2 from Tunisian scorpion venom glands-as well as its recombinant forms expressed in Escherichia coli-through interference with integrin receptor function in malignant glioma cells U87. These phospholipases inhibited in a dose dependent manner the adhesion, migration and invasion onto fibrinogen and fibronectin without any cytotoxicity. We showed that Sm-PLGV and its recombinant constructs blocked U87 migration by reducing their velocity and directional persistence. The inhibitory effect was related to a blockage of the integrins αvß3 and α5ß1 function. Inactivation of the enzymatic activity of Sm-PLGV by chemical modification with p-bromophenacyl bromide did not affect its anti-tumor properties, suggesting the presence of 'pharmacological sites' distinct from the catalytic site in scorpion venom phospholipases A2.
Assuntos
Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Glioblastoma/patologia , Integrina alfa5beta1/metabolismo , Integrina alfaVbeta3/metabolismo , Fosfolipases/farmacologia , Venenos de Escorpião/enzimologia , Animais , Linhagem Celular Tumoral , Humanos , Invasividade Neoplásica , Proteínas Recombinantes/farmacologiaRESUMO
Sea anemones are a remarkable source of active principles due to a decentralized venom system. New blood vessel growth or angiogenesis is a very promising target against cancer, but the few available antiangiogenic compounds have limited efficacy. In this study, a protein fraction, purified from tentacles of Anemonia viridis, was able to limit endothelial cells proliferation and angiogenesis at low concentration (14 nM). Protein sequences were determined with Edman degradation and mass spectrometry in source decay and revealed homologies with Blood Depressing Substance (BDS) sea anemones. The presence of a two-turn alpha helix observed with circular dichroism and a trypsin activity inhibition suggested that the active principle could be a Kunitz-type inhibitor, which may interact with an integrin due to an Arginine Glycin Aspartate (RGD) motif. Molecular modeling showed that this RGD motif was well exposed to solvent. This active principle could improve antiangiogenic therapy from existing antiangiogenic compounds binding on the Vascular Endothelial Growth Factor (VEGF).
Assuntos
Inibidores da Angiogênese/farmacologia , Proteínas/farmacologia , Anêmonas-do-Mar/metabolismo , Sequência de Aminoácidos , Inibidores da Angiogênese/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dicroísmo Circular , Humanos , Peso Molecular , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Oligopeptídeos/metabolismo , Proteínas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Cancer metastasis is the major cause of cancer-related death. Chemoprevention is defined as the use of natural or synthetic substances to prevent cancer formation or cancer progress. In the present study, we investigate the antitumor activity of esculin and its oligomer fractions in U87 glioblastoma cells. We showed that esculin and its oligomers reduced U87 cell growth in a dose dependent manner. They also inhibited cell adhesion to collagen IV and vitronectin by interfering with the function of their respective receptors α2ß1 and αvß5 integrins. Furthermore, the tested samples were able to reduce migration of U87 cells towards another extracellular matrix fibronectin. Moreover, esculin and its oligomer fractions inhibited in vitro angiogenesis of endothelial cells (HMEC-1). In summary, our data provide the first evidence that esculin and its oligomer fractions are able to reduce adhesion, migration of glioblastoma cells and in vitro angiogenesis. Esculin and its oligomers may thus exert multi-target functions against cancer cells.
Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Esculina/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Esculina/química , Glioblastoma/irrigação sanguínea , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Integrina alfa2beta1/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/prevenção & controle , Receptores de Vitronectina/metabolismoRESUMO
Laccase was used to enzymatically polymerize esculin. Oligoesculin fraction was obtained after ultrafiltration through a 5-kDa membrane. Several studies have been carried out to prove the effectiveness of natural substances such as immunomodulators to promote the anti-cancer activity in situ. The purpose of our report was to explore whether the anti-tumor potential of the oligoesculin fraction in vitro and in vivo is linked to its immunological mechanisms in melanoma-bearing mice. We revealed that oligoesculin fraction reduced B16-F10 proliferation and migration in vitro in a dose-related manner. Moreover, melanin synthesis and tyrosinase activity were inhibited in these melanoma cells in a concentration-dependent way. The anti-tumor potential of oligoesculin fraction was also assessed in vivo. Our results showed that intraperitoneal administration of oligoesculin fraction, at 50 mg/kg body weight (b.w.) for 21 days, reduced tumor size and weight with percentages of inhibition of 94 and 87 %, respectively. Oligoesculin fraction was effective in promoting lysosomal activity and nitric oxide (NO) production by peritoneal macrophages in tumor-implanted mice. In addition, the activities of natural killer (NK), cytotoxic T lymphocytes, and macrophages were significantly enhanced by oligoesculin fraction. These findings suggested that this polymer with its anti-tumor and immunomodulatory properties could be used for the treatment of melanoma.
Assuntos
Antineoplásicos/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Esculina/farmacologia , Melanoma Experimental/imunologia , Neoplasias Cutâneas/imunologia , Animais , Citotoxicidade Imunológica/imunologia , Fatores Imunológicos/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologiaRESUMO
PURPOSE: Non-small cell lung cancer (NSCLC) is one the types of cancer with higher prevalence and mortality. Apo2-Ligand/TRAIL is a TNF family member able to induce apoptosis in tumor cells but not in normal cells. It has been tested in clinical trials against different types of human cancer including NSCLC. However, results of clinical trials have shown a limited efficacy of TRAIL-based therapies. Recently we have demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) greatly improved TRAIL cytotoxic ability being capable of killing chemoresistant hematological cancer cells. In the present work we have extended the study to NSCLC. METHODS/PATIENTS: LUV-TRAIL-induced cytotoxicity was assessed on different NSCLC cell lines with different sensitivity to soluble TRAIL and on primary human tumor cells from three patients suffering from NSCLC cancer. We also tested LUV-TRAIL-cytotoxic ability in combination with several anti-tumor agents. RESULTS: LUV-TRAIL exhibited a greater cytotoxic effect compared to soluble TRAIL both in A549 cells and primary human NSCLC cells. LUV-TRAIL-induced cell death was dependent on caspase-8 and caspase-3 activation. Moreover, combination of LUV-TRAIL with other anti-tumor agents such as flavopiridol, and SNS-032 clearly enhanced LUV-TRAIL-induced cytotoxicity against NSCLC cancer cells. CONCLUSION: The novel formulation of TRAIL based on displaying it on the surface of lipid nanoparticles greatly increases its anti-tumor activity and has clinical potential in cancer treatment.