RESUMO
Stressful experience-induced cocaine-related behaviors are associated with a significant impairment of glutamatergic mechanisms in the Nucleus Accumbens core (NAcore). The hallmarks of disrupted glutamate homeostasis following restraint stress are the enduring imbalance of glutamate efflux after a cocaine stimulus and increased basal concentrations of extracellular glutamate attributed to GLT-1 downregulation in the NAcore. Glutamate transmission is tightly linked to microglia functioning. However, the role of microglia in the biological basis of stress-induced addictive behaviors is still unknown. By using minocycline, a potent inhibitor of microglia activation with anti-inflammatory properties, we determined whether microglia could aid chronic restraint stress (CRS)-induced glutamate homeostasis disruption in the NAcore, underpinning stress-induced cocaine self-administration. In this study, adult male rats were restrained for 2 h/day for seven days (day 1-7). From day 16 until completing the experimental protocol, animals received a vehicle or minocycline treatment (30 mg/Kg/12h i.p.). On day 21, animals were assigned to microscopic, biochemical, neurochemical or behavioral studies. We confirm that the CRS-induced facilitation of cocaine self-administration is associated with enduring GLT-1 downregulation, an increase of basal extracellular glutamate and postsynaptic structural plasticity in the NAcore. These alterations were strongly related to the CRS-induced reactive microglia and increased TNF-α mRNA and protein expression, since by administering minocycline, the impaired glutamate homeostasis and the facilitation of cocaine self-administration were prevented. Our findings are the first to demonstrate that minocycline suppresses the CRS-induced facilitation of cocaine self-administration and glutamate homeostasis disruption in the NAcore. A role of microglia is proposed for the development of glutamatergic mechanisms underpinning stress-induced vulnerability to cocaine addiction.
Assuntos
Cocaína , Animais , Cocaína/metabolismo , Ácido Glutâmico/metabolismo , Masculino , Microglia/metabolismo , Minociclina/metabolismo , Minociclina/farmacologia , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Plants in the Amaryllidaceae family synthesize a diversity of bioactive alkaloids. Some of these plant species are not abundant and have a low natural multiplication rate. The aims of this work were the alkaloids analysis of a Habranthus cardenasianus bulbs extract, the evaluation of its inhibitory activity against cholinesterases, and to test several propagation strategies for biomass production. Eleven compounds were characterized by GC-MS in the alkaloid extract, which showed a relatively high proportion of tazettine. The known alkaloids tazettine, haemanthamine, and the epimer mixture haemanthidine/6-epi-haemanthidine were isolated and identified by spectroscopic methods. Inhibitory cholinesterases activity was not detected. Three forms of propagation were performed: bulb propagation from seed, cut-induced bulb division, and micropropagated bulbs. Finally, different imbibition and post-collection times were evaluated in seed germination assays. The best propagation method was cut-induced bulb division with longitudinal cuts into quarters (T1) while the best conditions for seed germination were 0-day of post-collection and two days of imbibition. The alkaloids analyses of the H. cardenasianus bulbs showed that they are a source of anti-tumoral alkaloids, especially pretazettine (tazettine) and T1 is a sustainable strategy for its propagation and domestication to produce bioactive alkaloids.
Assuntos
Alcaloides/análise , Alcaloides/farmacologia , Amaryllidaceae/química , Amaryllidaceae/crescimento & desenvolvimento , Inibidores da Colinesterase/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides de Amaryllidaceae/análise , Biomassa , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Estrutura Molecular , Fenantridinas/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Fatores de TempoRESUMO
BACKGROUND: Gallbladder cancer (GBC) is the most common tumor of the biliary tract. The incidence of GBC shows a large geographic variability, being particularly frequent in Native American populations. In Chile, GBC represents the second cause of cancer-related death among women. We describe here the establishment of three novel cell lines derived from the ascitic fluid of a Chilean GBC patient, who presented 46% European, 36% Mapuche, 12% Aymara and 6% African ancestry. RESULTS: After immunocytochemical staining of the primary cell culture, we isolated and comprehensively characterized three independent clones (PUC-GBC1, PUC-GBC2 and PUC-GBC3) by short tandem repeat DNA profiling and RNA sequencing as well as karyotype, doubling time, chemosensitivity, in vitro migration capability and in vivo tumorigenicity assay. Primary culture cells showed high expression of CK7, CK19, CA 19-9, MUC1 and MUC16, and negative expression of mesothelial markers. The three isolated clones displayed an epithelial phenotype and an abnormal structure and number of chromosomes. RNA sequencing confirmed the increased expression of cytokeratin and mucin genes, and also of TP53 and ERBB2 with some differences among the three cells lines, and revealed a novel exonic mutation in NF1. The PUC-GBC3 clone was the most aggressive according to histopathological features and the tumorigenic capacity in NSG mice. CONCLUSIONS: The first cell lines established from a Chilean GBC patient represent a new model for studying GBC in patients of Native American descent.
Assuntos
Antígenos Glicosídicos Associados a Tumores/genética , Neoplasias da Vesícula Biliar/genética , Indígenas Sul-Americanos/genética , Animais , Antineoplásicos/farmacologia , Líquido Ascítico/metabolismo , Carcinogênese/genética , Testes de Carcinogenicidade , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Chile , Cisplatino/farmacologia , Células Clonais/efeitos dos fármacos , Células Clonais/metabolismo , Impressões Digitais de DNA , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Células Epiteliais/metabolismo , Neoplasias da Vesícula Biliar/metabolismo , Perfilação da Expressão Gênica , Genes erbB-2/genética , Humanos , Queratina-19/genética , Queratina-7/genética , Masculino , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Receptor ErbB-2/genética , Análise de Sequência de RNA , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , GencitabinaRESUMO
During gestation, low oxygen environment is a major determinant of early placentation process, while persistent placental hypoxia leads to pregnancy-related complications such as preeclampsia (PE) and intrauterine growth restriction (IUGR). PE affects 5%-8% of all pregnancies worldwide and is a cause of maternal and fetal morbidity and mortality. During placental development, persistent hypoxia due to poor trophoblast invasion and reduced uteroplacental perfusion leads to maternal endothelial dysfunction and clinical manifestation of PE. Here we hypothesized that nuclear factor of activated T cells-5 (NFAT5), a well-known osmosensitive renal factor and recently characterized hypoxia-inducible protein, is also activated in vivo in placentas of PE and IUGR complications as well as in the in vitro model of trophoblast hypoxia. In JAR cells, low oxygen tension (1% O2) induced NFAT5 mRNA and increased its nuclear abundance, peaking at 16 h. This increase did not occur in parallel with the earlier HIF1A induction. Real-time PCR and Western blot analysis confirmed up-regulation of NFAT5 mRNA and NFAT5 nuclear content in human preeclamptic placentas and in rabbit placentas of an experimentally induced IUGR model, as compared with the control groups. In vitro lambda protein phosphatase (lambda PPase) treatment revealed that increased abundance of NFAT5 protein in nuclei of either JAR cells (16 h of hypoxia) or PE and IUGR placentas is at least partially due to NFAT5 phosphorylation. NFAT5 downstream targets aldose reductase (AR) and sodium-myo-inositol cotransporter (SMIT; official symbol SLC5A3) were not significantly up-regulated either in JAR cells exposed to hypoxia or in placentas of PE- and IUGR-complicated pregnancies, suggesting that hypoxia-dependent activation of NFAT5 serves as a separate function to its tonicity-dependent stimulation. In conclusion, we propose that NFAT5 may serve as a novel marker of placental hypoxia and ischemia independently of HIF1A.
Assuntos
Retardo do Crescimento Fetal/metabolismo , Hipóxia/metabolismo , Fatores de Transcrição NFATC/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Regulação para Cima , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Retardo do Crescimento Fetal/genética , Humanos , Hipóxia/genética , Fatores de Transcrição NFATC/genética , Placentação/fisiologia , Pré-Eclâmpsia/genética , Gravidez , Coelhos , Trofoblastos/metabolismoRESUMO
A detailed chemical study of the aerial parts and rhizomes of Hyalis argentea var. latisquama yielded a variety of sesqui- and diterpenes. In total, 26 compounds were isolated and identified, of which four are new, namely, two ent-kaurenes (1 and 2), a diterpene lactone (3), and a lindenanolide (4). The previously reported compounds included a series of lindenanolides, guaianolides, elemanolides, and additional diterpenes. The antifungal activity of the isolated compounds was tested against Cryptococcus neoformans and Candida albicans. Among the isolated compounds, the lindenanolides were the only structural class that showed strong antifungal activity, and onoseriolide acetate (5) was the most active. On the other hand, the isolated guaianolides were only moderately active, while the diterpenes did not show significant antifungal activity.
Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Asteraceae/química , Diterpenos do Tipo Caurano/isolamento & purificação , Diterpenos do Tipo Caurano/farmacologia , Sesquiterpenos de Guaiano/isolamento & purificação , Sesquiterpenos de Guaiano/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Antifúngicos/química , Candida albicans/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Diterpenos do Tipo Caurano/química , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos de Guaiano/químicaRESUMO
Secochiliolide acid (1) isolated from the Patagonian shrub Nardophyllum bryoides, was used as a scaffold for the preparation of a series of nine derivatives. Compound 1 and its derivatives were tested against Trypanosoma cruzi epimastigotes grown in liquid media. It was first observed that secochiliolide acid (1) inhibited the proliferation of the parasites, with an IC50 of 2 µg/mL. Six of the synthesized derivatives were also active with IC50's between 2 and 7 µg/mL which are comparable to that of the commercial drug benznidazole (2.5 µg/mL). These results indicate that the carboxyl group is not essential for the bioactivity of 1, while the presence of the tetrasubstituted exocyclic double bond seems to be important. Moreover, the presence of the furan and spirolactone rings is not essential for the bioactivity per se, but is important in combination with other structural fragments present in the molecule.
Assuntos
Diterpenos/química , Diterpenos/farmacologia , Propionatos/química , Propionatos/farmacologia , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Asteraceae/química , Doença de Chagas/tratamento farmacológico , Humanos , Trypanosoma cruzi/crescimento & desenvolvimentoRESUMO
Five new neolignans with a bicyclo[2.2.2]octene framework were isolated from an ethanolic extract of the bark of Cordia americana. The structures and relative configurations of the compounds were elucidated by a combination of spectroscopic methods. All the isolated compounds showed good antioxidant activities in the DPPH radical scavenging (0.5-100 µg/mL) and Ferric-reducing antioxidant power (FRAP, 1-100 µg/mL) assays. One of the compounds displayed mild fungistatic activity at 0.1 µmol/spot against Fusarium virguliforme while, at the same time, all compounds were inactive against several strains of Gram (+) and Gram (-) bacteria at all assayed concentrations (10-1,000 µg/mL).
Assuntos
Antifúngicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Cordia/química , Lignanas/isolamento & purificação , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Compostos Bicíclicos com Pontes , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Fusarium/efeitos dos fármacos , Lignanas/química , Lignanas/farmacologia , Medicina Tradicional , Estrutura Molecular , Oxirredução , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Plantas MedicinaisRESUMO
Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disease that mainly affects tear and salivary glands, whereby SS-patients frequently complain of eye and mouth dryness. Salivary acinar cells of SS-patients display alterations in their cell polarity; which may affect the correct localization and function of proteins involved in regulated exocytosis. Here we determined whether the expression and localization of SNARE proteins (membrane fusion receptors) involved in regulated secretion, such as VAMP8, syntaxin 3 (STX3), STX4 and SNAP-23 were altered in salivary glands (SG) from SS-patients. Additionally, we investigated SNARE proteins function, by evaluating their ability to form SNARE complexes under basal conditions. In SG from SS-patients and control subjects mRNA and proteins levels of SNARE complex components were determined by real-time PCR and Western blotting, respectively. SNARE protein distribution and mucin exocytosis were determined by indirect immunofluorescence. In SS-patients, the expression levels of mRNA and protein for VAMP8, STX4 and STX3 were altered. STX4, STX3, SNAP-23 and VAMP8 relocated from the apical to the basal region of acinar cells. Increased formation of SNARE complexes in a manner independent of external stimuli for secretion was detected. Mucins were detected in the extracellular matrix (ECM). Presence of mucins in the ECM, together with the observed alterations in SNARE protein localization is indicative of ectopic exocytosis. In the context of SS, such aberrantly localized mucins are likely to favor a pro-inflammatory response, which may represent an important initial step in the pathogenesis of this disease.
Assuntos
Mucinas/metabolismo , Proteínas SNARE/metabolismo , Glândulas Salivares/metabolismo , Síndrome de Sjogren/metabolismo , Células Acinares/metabolismo , Adulto , Autoimunidade , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: To determine the expression and enzymatic activities of sulphotransferases involved in mucin hyposulphation in labial salivary glands (LSGs) from SS patients and to correlate sulphotransferase activity with clinical parameters such as secretion, inflammation and serology. METHODS: LSG from 31 SS patients and 31 control subjects were studied. Relative mRNA and protein levels of Gal3-O-sulphotransferases (Gal3STs) and ß1,3-galactosyltransferase-5 (ß3GalT5) were determined by quantitative RT-PCR and western blotting, respectively. Enzymatic activities were quantified using radioactively labelled donor substrates and specific acceptor substrates. Products were purified by chromatography. Spearman's correlation analysis was used to compare data. RESULTS: The levels of Gal3ST activity were significantly decreased in SS patients, without changes in mRNA and protein levels, while the enzymatic activities of glycosyltransferases involved in mucin glycosylation were similar in both groups. An inverse correlation was observed between Gal3ST activity and glandular function measured by scintigraphy, but not with unstimulated salivary flow. Gal3ST activity was inversely correlated with focus score, TNF-α levels and presence of the autoantibodies Ro/SS-A and La/SS-B. CONCLUSION: The decrease in sulphotransferase activity provides an explanation for mucin hyposulphation observed in the LSGs from SS patients. The decrease in Gal3STs activity was not a consequence of reduced gene expression, but probably due to alterations in the enzyme activity regulation. Interestingly, the levels of sulphotransferase activity detected correlated well with secretory function, inflammation and serology. Finally, we postulate that pro-inflammatory cytokines induced by autoantibodies, such as Ro/SS-A and La/SS-B in SS patients, may modulate Gal3ST activity, thereby altering mucin quality and leading to mouth dryness.
Assuntos
Galactosiltransferases/metabolismo , Mucina-5B/metabolismo , Glândulas Salivares Menores/enzimologia , Síndrome de Sjogren/enzimologia , Sulfurtransferases/metabolismo , Adulto , Idoso , Autoimunidade , Western Blotting , Estudos de Casos e Controles , Primers do DNA/química , Feminino , Glicosilação , Humanos , Imuno-Histoquímica , Inflamação/enzimologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sulfotransferases , Adulto JovemRESUMO
OBJECTIVE: Oral and ocular dryness are frequent and serious symptoms of Sjögren's syndrome (SS) that reflect problems in secretion due to glandular dysfunction. Exocytosis, an important process in the secretory pathway, requires the participation of Rab family GTPases. This study was undertaken to analyze the expression and localization of Rab3D and Rab8A and to examine their correlation with acinar cell polarity and glandular secretory function. METHODS: Nineteen patients with SS and 17 controls were evaluated. Levels of Rab3D and Rab8A messenger RNA (mRNA) and protein were determined by real-time polymerase chain reaction and Western blotting. Subcellular localization of proteins was determined by indirect immunofluorescence analysis. RESULTS: In patients with SS, total Rab3D protein levels decreased significantly, while mRNA levels remained unchanged. For Rab8A, no changes in either mRNA or protein levels were detected. In serous acini of labial salivary glands from patients with SS, the following 4 patterns of Rab3D staining were distinguishable: severely decreased, distribution throughout the cytoplasm, distribution throughout the cytoplasm combined with loss of nuclear polarity, and normal apical localization. Basal localization of Rab8A was not modified. Rab3D changes were accompanied by apicobasolateral redistribution of ezrin, loss of nuclear polarity, thicker Golgi stacks, and mucin 7 accumulation in the cytoplasm. Finally, low Rab3D protein levels correlated with alterations in scintigraphy measurements. CONCLUSION: Our findings indicate that Rab3D regulates the exocytosis of many components critical for the maintenance of oral physiology. Hence, the changes observed in Rab3D expression and distribution are likely to contribute to the decrease in or loss of saliva components (i.e., mucins), which may explain the variety of oral and ocular symptoms associated with SS.
Assuntos
Polaridade Celular/fisiologia , Glândulas Salivares/metabolismo , Síndrome de Sjogren/metabolismo , Proteínas rab3 de Ligação ao GTP/metabolismo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Sjogren/genética , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab3 de Ligação ao GTP/genéticaRESUMO
The infusion of the aerial parts of Gentianella multicaulis (Gillies ex Griseb.) Fabris (Gentianaceae), locally known as 'nencia', is used in San Juan Province, Argentina, as stomachic and as a bitter tonic against digestive and liver problems. The bioassay-guided isolation of G. multicaulis extracts and structural elucidation of the main compounds responsible for the antifungal and free radical scavenging activities were performed. The extracts had strong free radical scavenging effects in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (45-93% at 10 microg/mL) and ferric-reducing antioxidant power (FRAP) assay at 200 microg/mL. Demethylbellidifolin (4) had high antioxidant activity in the DPPH and FRAP assay. The dermatophytes Microsporum gypseum, Trichophyton mentagrophytes, and T. rubrum were moderately inhibited by the different extracts (MIC values of 125-250 microg/mL). Demethylbellidifolin (4), bellidifolin (5), and isobellidifolin (6) showed an antifungal effect (MIC values of 50 microg/mL), while swerchirin (3) was less active with a MIC value of 100 microg/mL. In addition, oleanolic acid (1) and ursolic acid (2) were also isolated. These findings demonstrate that Gentianella multicaulis collected in the mountains of the Province of San Juan, Argentina, is an important source of compounds with antifungal and antioxidant activities.
Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Gentianella/química , Argentina , Cromatografia Líquida de Alta Pressão , Sequestradores de Radicais Livres/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade MicrobianaRESUMO
Though the facilitating influence of stress on drug abuse is well documented, the mechanisms underlying this interaction have yet to be fully elucidated. The present study explores the neurobiological mechanisms underpinning the sensitized response to the psychomotor-stimulating effects of cocaine following chronic restraint stress (CRS), emphasizing the differential contribution of both subcompartments of the nucleus accumbens (NA), the core (NAcore) and shell (NAshell), to this phenomenon. Adult male Wistar rats were restrained for 2 h/day for 7 days and, 2 weeks after the last stress exposure (day 21), all animals were randomly assigned to behavioral, biochemical or neurochemical tests. Our results demonstrated that the enduring CRS-induced increase in psychostimulant response to cocaine was paralleled by an increase of extracellular dopamine levels in the NAcore, but not the NAshell, greater than that observed in the non-stress group. Furthermore, we found that CRS induced an impairment of glutamate homeostasis in the NAcore, but not the NAshell. Its hallmarks were increased basal extracellular glutamate concentrations driven by a CRS-induced downregulation of GLT-1, blunted glutamate levels in response to cocaine and postsynaptic structural remodeling in pre-stressed animals. In addition, ceftriaxone, a known GLT-1 enhancer, prevented the CRS-induced GLT-1 downregulation, increased basal extracellular glutamate concentrations and changes in structural plasticity in the NAcore as well as behavioral cross-sensitization to cocaine, emphasizing the biological importance of GLT-1 in the comorbidity between chronic stress exposure and drug abuse. A future perspective concerning the paramount relevance of the stress-induced disruption of glutamate homeostasis as a vulnerability factor to the development of stress and substance use disorders during early life or adulthood of descendants is provided.
RESUMO
Research for innovative drugs is crucial to contribute to parasitic infections control and eradication. Inspired by natural antiprotozoal triterpenes, a library of 12 hemisynthetic 3-O-arylalkyl esters was derived from ursolic and oleanolic acids through one-step synthesis. Compounds were tested on Trypanosoma, Leishmania and the WI38 cell line alongside with a set of triterpenic acids. Results showed that the triterpenic C3 esterification keeps the antitrypanosomal activity (IC50 ≈1.6-5.5â µm) while reducing the cytotoxicity compared to parent acids. Unsaturation of the ester alkyl chain leads to an activity loss interestingly kept when a sterically hindered group replaces the double bond or shields the ester group. An ursane/oleanane C3 hydroxylation was the only important feature for antileishmanial activity. Two candidates, dihydrocinnamoyl and 2-fluorophenylpropionyl ursolic acids, were tested on an acute mouse model of African trypanosomiasis with significant parasitemia reduction at day 5 post-infection for the dihydrocinnamoyl derivative. Further evaluation on other alkyl/protective groups should be investigated both inâ vitro and inâ vivo.
Assuntos
Ésteres/farmacologia , Triterpenos/farmacologia , Tripanossomicidas/farmacologia , Animais , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Ésteres/síntese química , Ésteres/toxicidade , Feminino , Leishmania mexicana/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Parasitária , Triterpenos/síntese química , Triterpenos/toxicidade , Tripanossomicidas/síntese química , Tripanossomicidas/toxicidade , Trypanosoma brucei brucei/efeitos dos fármacosRESUMO
Preclinical models of stress-induced relapse to drug use have shown that the dysregulation of glutamatergic transmission within the nucleus accumbens (NA) contributes notably to the reinstatement of cocaine-seeking behavior in rodents. In this sense, there has been increasing interest in the cannabinoid type-1 receptor (CB1R), due to its crucial role in modulating glutamatergic neurotransmission within brain areas involved in drug-related behaviors. This study explored the involvement of CB1R within the NA subregions in the restraint stress-induced reinstatement of cocaine-conditioned place preference (CPP), as well as in the regulation of glutamatergic transmission, by using a pharmacological approach and the in vivo microdialysis sampling technique in freely moving rats. CB1R blockade by the antagonist/inverse agonist AM251 (5 nmol/0.5 µl/side) or CB1R activation by the agonist ACEA (0.01 fmol/0.5 µl/side), prevented or potentiated restraint stress-induced reinstatement of cocaine-CPP, respectively, after local administration into NAcore, but not NAshell. In addition, microdialysis experiments demonstrated that restraint stress elicited a significant increase in extracellular glutamate in NAcore under reinstatement conditions, with the local administration of AM251 or ACEA inhibiting or potentiating this, respectively. Interestingly, this rise specifically corresponded to the cocaine-associated CPP compartment. We also showed that this context-dependent change in glutamate paralleled the expression of cocaine-CPP, and disappeared after the extinction of this response. Taken together, these findings demonstrated the key role played by CB1R in mediating reinstatement of cocaine-CPP after restraint stress, through modulation of the context-specific glutamate release within NAcore. Additionally, CB1R regulation of basal extracellular glutamate was demonstrated and proposed as the underlying mechanism.
Assuntos
Transtornos Relacionados ao Uso de Cocaína/etiologia , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Cocaína/efeitos adversos , Ácido Glutâmico/metabolismo , Núcleo Accumbens/metabolismo , Receptor CB1 de Canabinoide/agonistas , Estresse Fisiológico , Animais , Comportamento Animal , Biomarcadores , Condicionamento Clássico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Extinção Psicológica , Espaço Extracelular/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Estresse Fisiológico/genéticaRESUMO
Multiwalled carbon nanotubes (MWCNTs) are interesting high-tech nanomaterials. MWCNTs oxidized and functionalized with itaconic acid and monomethylitaconate were demonstrated to be efficient additives for controlling nucleation of calcium carbonate (CaCO3) via gas diffusion (GD) in classical as well as nonclassical crystallization, yielding aragonite and truncated calcite. For the first time, all amorphous calcium carbonate (ACC) proto-structures, such as proto calcite-ACC, proto vaterite-ACC and proto aragonite-ACC, were synthesized via prenucleation cluster (PNC) intermediates and stabilized at room temperature. The MWCNTs also showed concentration-dependent nucleation promotion and inhibition similar to biomolecules in nature. Incorporation of fluorescein-5-thiosemicarbazide (5-FTSC) dye-labeled MWCNTs into the CaCO3 lattice resulted in fluorescent hybrid nanosized CaCO3. We demonstrate that functionalized MWCNTs offer a good alternative for controlled selective crystallization and for understanding an inorganic mineralization process.
RESUMO
In the present study, a series of new esters of secochiliolide acid (SA), a diterpene isolated from Nardophyllum bryoides, were synthesized in good yield. All compounds were evaluated for their in vitro antiparasitic properties (on Plasmodium falciparum and Trypanosoma brucei brucei) and cytotoxicity (on WI38, normal mammalian cells). They displayed moderate antitrypanosomal activity with IC50 values between 2.55 and 18.14 µm, with selectivity indices >10, and low antiplasmodial effects with IC50 > 29 µm. The only exception was the n-hexyl ester of SA, which showed a strong and selective antiplasmodial activity (IC50 = 1.99 µm and selectivity index = 117.0). The in vivo antimalarial efficacy of this compound was then assessed according to the 4-day suppressive test of Peters in mice. An intraperitoneal treatment at 50 mg kg-1 day-1 induced a slight parasitaemia reduction by 56% which was statistically significant on day 4 post-infection and an increase in the survival time.
Assuntos
Antimaláricos/química , Antiprotozoários/química , Diterpenos/química , Ésteres/química , Propionatos/química , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Asteraceae/química , Asteraceae/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Humanos , Extratos Vegetais/química , Plasmodium falciparum/efeitos dos fármacos , Propionatos/isolamento & purificação , Propionatos/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacosRESUMO
The antifouling activity of peracetylated cholic acid (1), a bile acid derivative which was isolated in a previous work as a natural product from the Patagonian sponge Siphonochalina fortis, was evaluated in laboratory and field trials. Toxicity and settlement assays were performed with the mussel Mytilus edulis platensis, while the field trials were carried out by addition of the compound to experimental soluble-matrix paints, which were then tested in the sea. The results obtained in this work show that 1 has a good antifouling activity and low toxicity, and the paints aditivated with 0,6% Wt showed promissory performances in the field trials at the sea. These results confirm the previous hypothesis that the few acetylated and lipophilic bile acid derivatives isolated from marine invertebrates may act as natural antifoulants. Compound 1 is a natural, biodegradable product that can be easily prepared from cholic acid, which in turn can be isolated in industrial scale from cattle bile. All these facts make cholic acid a good scaffold for the preparation of derivatives, which can be natural product-like, effective and sustainable antifouling additives for marine paints and other applications.
Assuntos
Incrustação Biológica/prevenção & controle , Ácido Cólico/química , Ácido Cólico/farmacologia , Acetilação , Animais , Bivalves/efeitos dos fármacos , Bivalves/metabolismoRESUMO
Trophoblast cells are often compared to highly invasive carcinoma cells due to their capacity to proliferate in hypoxic conditions and to exhibit analogous vascular, proliferative, migratory, and invasive capacities. Thus, genes that are important for tumorigenesis, such as forkhead box M1 ( FOXM1) may also be involved in processes of trophoblast invasion. Indeed, we found Foxm1 protein and messenger RNA (mRNA) levels decreased as gestational age increased in rat's placentae. Accordingly, when mimicking early placental events in vitro, protein and mRNA expression of FOXM1 increased from 21% to 8% O2, reaching its highest expression at 3% oxygen tension, which reflects early implantation environment, and dropping to very low levels at 1% O2. Remarkably, FOXM1 silencing in JEG-3 cells was able to significantly decrease migration by 27.9%, in comparison with those cells transfected with control siRNA. Moreover, angiogenesis was compromised when conditioned media (CM) from FOXM1-siRNA -JEG-3 (3% O2) was added to human umbilical vein endothelial cells (HUVEC) cells; however, when CM of JEG-3 cells overexpressing FOXM1 at 1% O2 was added, the ability of HUVEC to form tubule networks was restored. Additionally, quantitative real-time polymerase chain reaction (PCR) assays of FOXM1 knockdown and overexpression experiments in JEG-3 cells revealed that the depletion of FOXM1 at 3% O2 and overexpression of FOXM1 at 1% O2 led to downregulation and upregulation of vascular endothelial growth factor transcriptional (VEGF) levels, respectively. Conversely, we also observed deregulation of FOXM1 in placentae derived from pregnancies complicated by preeclampsia (PE). Therefore, we demonstrate that FOXM1 may be a new regulatory protein of early placentation processes and that under chronic hypoxic conditions (1% O2) and in patients with severe PE, its levels decrease.
Assuntos
Proteína Forkhead Box M1/metabolismo , Neovascularização Patológica/metabolismo , Placentação , Pré-Eclâmpsia/metabolismo , Trofoblastos/metabolismo , Animais , Linhagem Celular , Movimento Celular , Células Endoteliais , Feminino , Gravidez , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Veias Umbilicais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The triterpene oleanolic acid 1 and its semisynthetic derivatives 2-7 were assessed for gastroprotective and ulcer-healing effect using human epithelial gastric cells (AGS) and human lung fibroblasts (MRC-5). The ability of the compounds to protect the AGS cells against the damage induced by sodium taurocholate (NaT), to stimulate the cellular reduced glutathione (GSH) and prostaglandin E(2) content, to enhance AGS and MRC-5 cell proliferation and to scavenge superoxide anion in vitro was studied. The cytotoxicity of the compounds was assessed towards MRC-5 and AGS cells. In addition, the gastroprotective activity of the compounds was assessed in vivo using the HCl/EtOH-induced ulcer model in mice. All the assayed compounds displayed a significant reduction of AGS cells damage after incubation with NaT. None of the studied compounds was active as a superoxide anion scavenger nor stimulated the GSH content in AGS cell cultures. Compounds 1, 2, 4 and 6 were able to increase the prostaglandin content in AGS cell cultures. Concerning the proliferation assays, a significant stimulating effect was observed for compounds 3 and 7 on AGS cells and for 1 and 7 on MRC-5 fibroblasts. Regarding cytotoxicity, derivatives 2, 4, 6 and 7 were less toxic than the parent compound oleanolic acid. Our results strongly support the predictive capacity of the in vitro assessment of gastroprotective activity allowing the reduction of experimental animals.
Assuntos
Antiulcerosos/uso terapêutico , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , Úlcera Gástrica/prevenção & controle , 2-Piridinilmetilsulfinilbenzimidazóis , Animais , Antiulcerosos/síntese química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Depressores do Sistema Nervoso Central , Fenômenos Químicos , Físico-Química , Dinoprostona/metabolismo , Células Epiteliais , Etanol , Fibroblastos , Sequestradores de Radicais Livres/farmacologia , Mucosa Gástrica/citologia , Mucosa Gástrica/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Ácido Clorídrico , Lansoprazol , Masculino , Camundongos , Ácido Oleanólico/síntese química , Omeprazol/análogos & derivados , Omeprazol/farmacologia , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Superóxidos/metabolismo , Ácido Taurocólico/antagonistas & inibidores , Ácido Taurocólico/toxicidadeRESUMO
Introducción: El consumo de drogas ilegales por los adolescentes se considera en la actualidad, como un problema de salud pública a nivel mundial. Cuba no está exenta de esta problemática. Una vez instaurada la adicción, el estilo de vida que desarrolle cada individuo es determinante para el proceso de recuperación. Objetivo: Caracterizar el estilo de vida de adolescentes adictos a drogas ilegales en la etapa de recuperación. Métodos: La investigación se basó en un diseño mixto y consistió en el estudio de los 26 adolescentes adictos a drogas ilegales que fueron atendidos en el Departamento de Salud Mental del municipio Playa, La Habana, Cuba, durante el primer trimestre de 2018. Se aplicó el Cuestionario de Estilo de Vida Promotor de Salud y se realizaron cuatro grupos focales. Resultados: Los 26 sujetos evaluados presentaron una conducta irresponsable ante la salud y el cuidado de sí mismo. No obstante, el soporte interpersonal fue adecuado en 76,9 por ciento de los casos estudiados, y 46,15 por ciento de ellos presentó habilidades para manejo adecuado del estrés. Fue identificada la carencia de hábitos adecuados de ejercitación física (73,1 por ciento) y de comportamientos nutricionales y de autoactualización (69,2 por ciento). Conclusiones: Las adicciones constituyen un trastorno crónico y el tratamiento para la recuperación tiene entre sus pilares principales la modificación del estilo de vida. El apoyo interpersonal y las habilidades para manejar el estrés que logre desarrollar el paciente adicto pueden ayudarlo asumir su estilo de vida, y su salud con más responsabilidad. Para que el proceso de recuperación concluya satisfactoriamente y se eviten recaídas desmoralizantes, debe procurarse la adecuación de la autoestima, el compromiso con proyectos de vida realistas y la satisfacción con su situación personal(AU)
Introduction: The use of illegal drugs by adolescents is nowadays considered as a global public health problem. Cuba is not an exception of this problem. Once the addiction is established, the lifestyle developed by each individual is determinant for the recovery process. Objective: Characterize the lifestyle of adolescents addicted to illegal drugs in the recovery stage. Methods: The research was based in mixed design and consisted in the study of 26 adolescents addicted to illegal drugs whom were attended in the Mental Health Service of Playa municipality, Havana, Cuba during the first quarter of 2018. It was applied the Questionnaire of Lifestyle - Health Promoter and four focus groups were formed. Results: The 26 patients assessed showed an irresponsible behaviour towards health and self-care. However, the interpersonal support was adequate in 76,9percent of the studied cases, and 46,15percent of them presented skills for an adequate management of stress. It was identified lack of adequate habits of physical activity (73,1percent) and of nutritional behaviours and auto-updating (69,2percent). Conclusions: Addictions are a chronic disorder and the treatment for recovery has among its pillars the modification of lifestyle. Interpersonal support and skills to manage stress that the addict patient is able to develop would help to assume his-her lifestyle and health with more responsibility. In order that the recovery process ends up satisfactorily and to avoid that demoralizing relapses occur, it must be seek the adequacy of self-steem, the commitment with realistic life projects and satisfaction with the personal situation(AU)