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1.
Clin Sci (Lond) ; 137(15): 1049-1066, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37477956

RESUMO

Heart failure (HF) is characterized by reduced ventricular function, compensatory activation of neurohormonal mechanisms and marked autonomic imbalance. Exercise training (T) is effective to reduce neurohormonal activation but the mechanism underlying the autonomic dysfunction remains elusive. Knowing that blood-brain barrier (BBB) lesion contributes to autonomic imbalance, we sought now to investigate its involvement in HF- and exercise-induced changes of autonomic control. Wistar rats submitted to coronary artery ligation or SHAM surgery were assigned to T or sedentary (S) protocol for 8 weeks. After hemodynamic/autonomic recordings and evaluation of BBB permeability, brains were harvesting for ultrastructural analysis of BBB constituents, measurement of vesicles trafficking and tight junction's (TJ) tightness across the BBB (transmission electron microscopy) and caveolin-1 and claudin-5 immunofluorescence within autonomic brain areas. HF-S rats versus SHAM-S exhibited reduced blood pressure, augmented vasomotor sympathetic activity, increased pressure and reduced heart rate variability, and, depressed reflex sensitivity. HF-S also presented increased caveolin-1 expression, augmented vesicle trafficking and a weak TJ (reduced TJ extension/capillary border), which determined increased BBB permeability. In contrast, exercise restored BBB permeability, reduced caveolin-1 content, normalized vesicles counting/capillary, augmented claudin-5 expression, increased TJ tightness and selectivity simultaneously with the normalization of both blood pressure and autonomic balance. Data indicate that BBB dysfunction within autonomic nuclei (increased transcytosis and weak TJ allowing entrance of plasma constituents into the brain parenchyma) underlies the autonomic imbalance in HF. Data also disclose that exercise training corrects both transcytosis and paracellular transport and improves autonomic control even in the persistence of cardiac dysfunction.


Assuntos
Insuficiência Cardíaca , Doenças Vasculares , Ratos , Animais , Barreira Hematoencefálica/metabolismo , Caveolina 1/metabolismo , Claudina-5/metabolismo , Ratos Wistar , Doenças Vasculares/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura
2.
J Microencapsul ; 40(7): 549-565, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37698449

RESUMO

The aim of this work was to investigate novel formulations containing diruthenium(II-III)-ibuprofen (RuIbp) metallodrug encapsulated into the chitosan (CT) biopolymer. Microparticles (RuIbp/CT MPs, ∼ 1 µm) were prepared by spray-drying, and RuIbp/CT-crosslinked nanoparticles (NPs) by ionic gelation (RuIbp/CT-TPP, TPP = tripolyphosphate (1), RuIbp/CT-TPP-PEG, PEG = poly(ethyleneglycol (2)) or pre-gel/polyelectrolyte complex method (RuIbp/CT-ALG, ALG = alginate (3)). Ru analysis was conducted by energy dispersive x-ray fluorescence or inductively coupled plasma atomic emission spectroscopy, and physicochemical characterisation by powder x-ray diffraction, electronic absorption and FTIR spectroscopies, electrospray ionisation mass spectrometry, thermal analysis, scanning electron, transition electron and atomic force microscopies, and dynamic light scattering. The RuIbp-loaded nanosystems exhibited encapsulation efficiency ∼ 20-37%, drug loading∼ 10-20% (w/w), hydrodynamic diameter (nm): 103.2 ± 7.9 (1), 91.7 ± 12.6 (2), 270.2 ± 58.4 (3), zeta potential (mV): +(47.7 ± 2.8) (1), +(49.2 ± 3.6) (2), -(28.2 ± 2.0) (3). Nanoformulation (1) showed the highest cytotoxicity with increased efficacy in relation to the RuIbp free metallodrug against U87MG human glioma cells.

3.
J Biomed Sci ; 28(1): 14, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33610185

RESUMO

BACKGROUND: Glutaminase isoenzymes GLS and GLS2 play apparently opposing roles in cancer: GLS acts as an oncoprotein, while GLS2 (GAB isoform) has context specific tumour suppressive activity. Some microRNAs (miRNAs) have been implicated in progression of tumours, including gliomas. The aim was to investigate the effect of GLS and GAB expression on both miRNAs and oxidative status in glioblastoma cells. METHODS: Microarray profiling of miRNA was performed in GLS-silenced LN229 and GAB-transfected T98G human glioblastoma cells and their wild-type counterparts. Results were validated by real-time quantitative RT-PCR. Oxidative status and antioxidant enzymes were determined by spectrophotometric or fluorescence assays in GLS-silenced LN229 and T98G, and GAB-transfected LN229 and T98G. RESULTS: MiRNA-146a-5p, miRNA-140-3p, miRNA-21-5p, miRNA-1260a, and miRNA-92a-3p were downregulated, and miRNA-1246 was upregulated when GLS was knocked down. MiRNA-140-3p, miRNA-1246, miRNA-1260a, miRNA-21-5p, and miRNA-146a-5p were upregulated when GAB was overexpressed. Oxidative status (lipid peroxidation, protein carbonylation, total antioxidant capacity, and glutathione levels), as well as antioxidant enzymes (catalase, superoxide dismutase, and glutathione reductase) of silenced GLS glioblastoma cells and overexpressed GAB glioblastoma cells significantly changed versus their respective control glioblastoma cells. MiRNA-1246, miRNA-1260a, miRNA-146a-5p, and miRNA-21-5p have been characterized as strong biomarkers of glioblastoma proliferation linked to both GLS silencing and GAB overexpression. Total glutathione is a reliable biomarker of glioblastoma oxidative status steadily associated to both GLS silencing and GAB overexpression. CONCLUSIONS: Glutaminase isoenzymes are related to the expression of some miRNAs and may contribute to either tumour progression or suppression through certain miRNA-mediated pathways, proving to be a key tool to switch cancer proliferation and redox status leading to a less malignant phenotype. Accordingly, GLS and GAB expression are especially involved in glutathione-dependent antioxidant defence.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glutaminase/genética , MicroRNAs/metabolismo , Estresse Oxidativo , Linhagem Celular Tumoral , Regulação para Baixo , Glutaminase/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Regulação para Cima
4.
Int J Mol Sci ; 22(9)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919029

RESUMO

Prostaglandin E2 (PGE2) is known to increase glioblastoma (GBM) cell proliferation and migration while cyclooxygenase (COX) inhibition decreases proliferation and migration. The present study investigated the effects of COX inhibitors and PGE2 receptor antagonists on GBM cell biology. Cells were grown with inhibitors and dose response, viable cell counting, flow cytometry, cell migration, gene expression, Western blotting, and gelatin zymography studies were performed. The stimulatory effects of PGE2 and the inhibitory effects of ibuprofen (IBP) were confirmed in GBM cells. The EP2 and EP4 receptors were identified as important mediators of the actions of PGE2 in GBM cells. The concomitant inhibition of EP2 and EP4 caused a significant decrease in cell migration which was not reverted by exogenous PGE2. In T98G cells exogenous PGE2 increased latent MMP2 gelatinolytic activity. The inhibition of COX1 or COX2 caused significant alterations in MMP2 expression and gelatinolytic activity in GBM cells. These findings provide further evidence for the importance of PGE2 signalling through the EP2 and the EP4 receptor in the control of GBM cell biology. They also support the hypothesis that a relationship exists between COX1 and MMP2 in GBM cells which merits further investigation as a novel therapeutic target for drug development.


Assuntos
Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Inibidores de Ciclo-Oxigenase/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Apoptose , Biomarcadores Tumorais/genética , Ciclo Celular , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Invasividade Neoplásica , Células Tumorais Cultivadas
5.
Prostaglandins Other Lipid Mediat ; 150: 106452, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32439412

RESUMO

Glioblastoma multiforme (GBM) is the most malignant astrocytoma, the main treatments consist of surgical resection followed by radiotherapy and chemotherapy. Patients, after diagnosed, have a survival rate of one year. GBM cells have an invasive, proliferative and migratory characteristic, also they do not respond properly for usual cancer treatment (radiotherapy, chemotherapy). Fatty acids have been studied as an adjuvant cancer treatment in breast, colorectal and GBM. The fatty acid can alter tumoural cell metabolism causing a modification of eicosanoids production. This study has observed some cellular aspects modified by fatty acid treatment in vitro, using GBM cells (human and rat). Modifications in cell behaviour were analyzed like cell proliferation, apoptosis, migration and invasion cell capacity after treatment with fatty acid (gamma-linolenic acid). The treatment suggested in this study showed an increased number of apoptotic cells and a decreased number of proliferative and migratory cells. These data recognize that gamma-linolenic acid could be used as an alternative treatment for glioblastoma.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Ácido gama-Linolênico/farmacologia , Animais , Apoptose/efeitos dos fármacos , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Ratos , Células Tumorais Cultivadas
6.
Int J Mol Sci ; 21(21)2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182324

RESUMO

BACKGROUND: The relationship between glioblastoma (GBM) and fatty acid metabolism could be the key to elucidate more effective therapeutic targets. 15-lipoxygenase-1 (15-LOX), a linolenic acid and arachidonic acid metabolizing enzyme, induces both pro- and antitumorigenic effects in different cancer types. Its role in glioma activity has not yet been clearly described. The objective of this study was to identify the influence of 15-LOX and its metabolites on glioblastoma cell activity. METHODS: GBM cell lines were examined using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to identify 15-LOX metabolites. GBM cells treated with 15-LOX metabolites, 13-hydroxyoctadecadeinoic acid (HODE) and 9-HODE, and two 15-LOX inhibitors (luteolin and nordihydroguaiaretic acid) were also examined. Dose response/viability curves, RT-PCRs, flow cytometry, migration assays, and zymograms were performed to analyze GBM growth, migration, and invasion. RESULTS: Higher quantities of 13-HODE were observed in five GBM cell lines compared to other lipids analyzed. Both 13-HODE and 9-HODE increased cell count in U87MG. 15-LOX inhibition decreased migration and increased cell cycle arrest in the G2/M phase. CONCLUSION: 15-LOX and its linoleic acid (LA)-derived metabolites exercise a protumorigenic influence on GBM cells in vitro. Elevated endogenous levels of 13-HODE called attention to the relationship between linoleic acid metabolism and GBM cell activity.


Assuntos
Araquidonato 15-Lipoxigenase/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Inibidores de Lipoxigenase/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Ácido Linoleico/metabolismo , Ácidos Linoleicos/metabolismo , Ácidos Linoleicos Conjugados/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-29042181

RESUMO

BACKGROUND: The World Health Organization classifies glioblastoma (GBM) as a grade IV astrocytoma. Despite the advances in chemotherapy, surgery, and radiation treatments that improve a patient's length of survival, the overall trajectory of the disease remains unchanged. GBM cells produce significant levels of various types of bioactive lipids. Prostaglandin D2 (PGD2) influences both pro- and anti-tumorigenic activities in the cell; however, its role in GBM is unclear. Therefore, this study aimed to identify the impact of PGD2 on GBM cell activities in vitro. METHODS: First we looked to identify the presence of the PGD2 synthesis pathway through RT-PCR, immunohistochemistry, and HPLC-MS/MS in three GBM cell lines. Then, to observe PGD2's effects on cell count and apoptosis/mitosis (Hoechst 33342 stain), and migration (Transwell Assay), the cells were treated in vitro with physiological (<1µM) and/or supraphysiological (>1µM) concentrations of PGD2 over 72h. HPLC-MS/MS was used to identify the lipid composition of patients with either Grade II/III gliomas or GBM. RESULTS: We identified the presence of endogenous PGD2 with its corresponding enzymes and receptors. Exogenous PGD2 both increased cell count (<1µM) and decreased cell count (10µM) in a concentration-dependent manner. There were no significant effects on apoptosis. A significant decrease in mitotic activity was seen only in U251MG, and a significant increase was seen in migration with 5µM PGD2 treatments. A very significant increase of PGD2 was seen from Grade II/III gliomas to GBM. CONCLUSIONS: Our study demonstrates that prostaglandin D2 possesses a dynamic, concentration-dependent effect in GBM cell activities. The increase of PGD2 production in GBM patients suggests a pro-tumorigenic role of PGD2 in glioma growth and invasion. Therefore, prostaglandin signaling in GBM requires further investigation to identify new targets for more effective therapies.


Assuntos
Glioblastoma/metabolismo , Prostaglandina D2/metabolismo , Apoptose , Movimento Celular , Glioblastoma/patologia , Humanos , Mitose , Prostaglandina D2/biossíntese , Transdução de Sinais
8.
Artigo em Inglês | MEDLINE | ID: mdl-29966699

RESUMO

Prostanoids derived from the activity of cyclooxygenases and their respective synthases contribute to both active inflammation and immune response in the tumor microenvironment. Their synthesis, deactivation and role in glioma biology have not yet been fully explored and require further study. Using quantitative real time PCR, gas chromatography/ electron impact mass spectrometry and liquid chromatography/ electrospray ionization tandem mass spectrometry, we have further characterized the prostanoid pathway in grade IV glioblastoma (GBM). We observed significant correlations between high mRNA expression levels and poor patient survival for microsomal PGE synthase 1 (mPGES1) and prostaglandin reductase 1 (PTGR1). Conversely, high mRNA expression levels for 15-hydroxyprostaglandin dehydrogenase (15-HPGD) were correlated with better patient survival. GBMs had a higher quantity of the prostanoid precursor, arachidonic acid, versus grade II/III tumors and in GBMs a significant positive correlation was found between arachidonic acid and PGE2 content. GBMs also had higher concentrations of TXB2, PGD2, PGE2 and PGF2α versus grade II/III tumors. A significant decrease in survival was detected for high versus low PGE2, PGE2 + PGE2 deactivation products (PGEMs) and PGF2α in GBM patients. Our data show the potential importance of prostanoid metabolism in the progression towards GBM and provide evidence that higher PGE2 and PGF2α concentrations in the tumor are correlated with poorer patient survival. Our findings highlight the potential importance of the enzymes 15-HPGD and PTGR1 as prognostic biomarkers which could be used to predict survival outcome of patients with GBM.


Assuntos
Biomarcadores Tumorais/metabolismo , Glioblastoma , Proteínas de Neoplasias/metabolismo , Prostaglandinas/metabolismo , Adulto , Intervalo Livre de Doença , Feminino , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
9.
Artigo em Inglês | MEDLINE | ID: mdl-26872995

RESUMO

Seasonal plasticity in the small intestine of neonatal tegu lizards was investigated using morphometry and analysis of enzymes involved in supplying energy to the intestinal tissue. In the autumn, the intestinal mass (Mi) was 1.0% of body mass and the scaling exponent b=0.92 indicated that Mi was larger in smaller neonates. During arousal from dormancy Mi was 23% smaller; later in spring, Mi increased 60% in relation to the autumn and the exponent b=0.14 indicated that the recovery was disproportionate in smaller tegus. During the autumn, the intestinal villi were greatly elongated; by midwinter, the Hv, SvEp, and VvEp were smaller than during the autumn (59%, 54%, 29%) and were restored to autumn levels during spring. In the active tegus, the maximum activity (Vmax) of enzymes indicated that the enterocytes can obtain energy from different sources, and possess gluconeogenic capacity. During winter, the Vmax of CS, HOAD, GDH, PEPCK was 40-50% lower in relation to the autumn and spring, while the Vmax of HK, PK, LDH, AST was unchanged. The hypoglycemia and the mucosal atrophy/ischemia during winter would prevent the enterocytes from using glucose, whereas they could slowly oxidize fatty acids released from body stores and amino acids from the tissue proteolysis to satisfy their needs of energy. Contrastingly, starvation during spring caused severe mass loss (50%); the tissue protein and the VvEp and VvLP did not change while the thickness of the muscular layer increased 51%, which suggested different effects along the length of the organ. In addition, the Vmax of the glycolytic enzymes was lower, indicating that a regulatory mechanism would spare blood glucose for vital organs during unanticipated food restriction.


Assuntos
Jejum , Hibernação , Intestino Delgado/metabolismo , Lagartos/fisiologia , Animais , Peso Corporal , Lagartos/crescimento & desenvolvimento , Estações do Ano
10.
J Biol Chem ; 289(24): 16711-26, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24764300

RESUMO

Intracellular peptides are constantly produced by the ubiquitin-proteasome system, and many are probably functional. Here, the peptide WELVVLGKL (pep5) from G1/S-specific cyclin D2 showed a 2-fold increase during the S phase of HeLa cell cycle. pep5 (25-100 µm) induced cell death in several tumor cells only when it was fused to a cell-penetrating peptide (pep5-cpp), suggesting its intracellular function. In vivo, pep5-cpp reduced the volume of the rat C6 glioblastoma by almost 50%. The tryptophan at the N terminus of pep5 is essential for its cell death activity, and N terminus acetylation reduced the potency of pep5-cpp. WELVVL is the minimal active sequence of pep5, whereas Leu-Ala substitutions totally abolished pep5 cell death activity. Findings from the initial characterization of the cell death/signaling mechanism of pep5 include caspase 3/7 and 9 activation, inhibition of Akt2 phosphorylation, activation of p38α and -γ, and inhibition of proteasome activity. Further pharmacological analyses suggest that pep5 can trigger cell death by distinctive pathways, which can be blocked by IM-54 or a combination of necrostatin-1 and q-VD-OPh. These data further support the biological and pharmacological potential of intracellular peptides.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclina D2/farmacologia , Oligopeptídeos/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Motivos de Aminoácidos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Ciclo Celular , Ciclina D2/química , Glioblastoma/tratamento farmacológico , Células HeLa , Humanos , Imidazóis/farmacologia , Indóis/farmacologia , Células MCF-7 , Masculino , Maleimidas/farmacologia , Oligopeptídeos/química , Oligopeptídeos/uso terapêutico , Quinolinas/farmacologia , Ratos , Ratos Wistar
11.
J Transl Med ; 12: 75, 2014 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-24655332

RESUMO

BACKGROUND: Prevailingly, adult mammalian neurogenesis is thought to occur in discrete, separate locations known as neurogenic niches that are best characterized in the subgranular zone (SGZ) of the dentate gyrus and in the subventricular zone (SVZ). The existence of adult human neurogenic niches is controversial. METHODS: The existence of neurogenic niches was investigated with neurogenesis marker immunostaining in histologically normal human brains obtained from autopsies. Twenty-eight adult temporal lobes, specimens from limbic structures and the hypothalamus of one newborn and one adult were examined. RESULTS: The neural stem cell marker nestin stained circumventricular organ cells and the immature neuronal marker doublecortin (DCX) stained hypothalamic and limbic structures adjacent to circumventricular organs; both markers stained a continuous structure running from the hypothalamus to the hippocampus. The cell proliferation marker Ki-67 was detected predominantly in structures that form the septo-hypothalamic continuum. Nestin-expressing cells were located in the fimbria-fornix at the insertion of the choroid plexus; ependymal cells in this structure expressed the putative neural stem cell marker CD133. From the choroidal fissure in the temporal lobe, a nestin-positive cell layer spread throughout the SVZ and subpial zone. In the subpial zone, a branch of this layer reached the hippocampal sulcus and ended in the SGZ (principally in the newborn) and in the subiculum (principally in the adults). Another branch of the nestin-positive cell layer in the subpial zone returned to the optic chiasm. DCX staining was detected in the periventricular and middle hypothalamus and more densely from the mammillary body to the subiculum through the fimbria-fornix, thus running through the principal neuronal pathway from the hippocampus to the hypothalamus. The column of the fornix forms part of this pathway and appears to coincide with the zone previously identified as the human rostral migratory stream. Partial co-labeling with DCX and the neuronal marker ßIII-tubulin was also observed. CONCLUSIONS: Collectively, these findings suggest the existence of an adult human neurogenic system that rises from the circumventricular organs and follows, at minimum, the circuitry of the hypothalamus and limbic system.


Assuntos
Encéfalo/fisiologia , Neurogênese , Adulto , Idoso , Encéfalo/citologia , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Células-Tronco Neurais/citologia , Adulto Jovem
12.
J Biol Inorg Chem ; 19(6): 1025-35, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24824561

RESUMO

The Diruthenium-Ibuprofen compound [Ru2Cl(Ibp)4] (or RuIbp) is known to cause significant inhibition of C6 rat glioma cell proliferation in vitro. RuIbp increased the expression of cell cycle-related proteins such as p21 and p27 and the pro-apoptotic protein Bax, as well as causing a reduction in mitochondrial membrane potential and a modest increase in apoptosis in vitro. The present study extended these findings by (i) investigating the effects of RuIbp on human glioma cell line proliferation in vitro and (ii) investigating the acute and chronic toxicology of the compound in normal Wistar rats. The compound was then tested for its anti-tumour properties by either chronic 14 days intra-peritoneal (IP) administration or chronic Alzet osmotic pump infusion, in the rat C6 orthotopic glioma model in vivo. The IP injection of RuIbp caused a 41 % inhibition of tumour area without significant toxic effects but with an increase in blood neutrophils and monocytes and a decrease in blood lymphocytes. In an attempt to reduce this effect RuIbp was administered by Alzet osmotic pump infusion directly into the tumour at a dose of 15 mg/kg with an infusion rate of 0.5 µL/h for 14 days. The direct infusion of RuIbp caused a 45 % inhibition of tumour area without alterations in differential blood leukocyte counts. These results prove the efficacy of RuIbp in human glioma cell lines in vitro and in an in vivo glioma model and point to its potential as an inhibitor of tumour growth in vivo.


Assuntos
Antineoplásicos/farmacologia , Glioma/tratamento farmacológico , Glioma/patologia , Ibuprofeno/química , Neoplasias Experimentais/tratamento farmacológico , Compostos Organometálicos/farmacologia , Rutênio/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Neoplasias Experimentais/patologia , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Células Tumorais Cultivadas
13.
Artigo em Inglês | MEDLINE | ID: mdl-23603066

RESUMO

Morpho-functional adjustments in the heart of juvenile tegu lizards (Tupinambis merianae) were analyzed at distinct seasonal periods to investigate how the demands of growth and of energy saving are reconciled during the first annual cycle. The relative ventricular mass (Mv) was 31% and 69% larger in late autumn and winter dormancy, respectively, compared to early autumn. This effect did not persist during unfed arousal, suggesting that protein accumulates in the heart during hypometabolism and is degraded on arousal. Both the hypertrophy and the atrophy were disproportionate in the largest individuals. In contrast, Mv was smaller in lizards that were starved during spring activity compared to fed lizards, this effect being larger in smaller individuals. In late autumn and winter dormancy the spongy myocardium had 8% of the section area covered by lacunary spaces, which expanded after food intake during arousal and reached 29% in spring activity together with higher density of cardiomyocytes. Total and soluble proteins per mass unity were unchanged, and maximum activities of selected enzymes suggest sustained glycolytic and aerobic capacities during hypometabolism. Results indicate that important structural adjustments occur in the heart in anticipation of dormancy, and that the protein balance in the tissue is maintained at winter temperatures ~17°C.


Assuntos
Cardiomegalia/veterinária , Lagartos/fisiologia , Miócitos Cardíacos/metabolismo , Animais , Índice de Massa Corporal , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatologia , Ingestão de Alimentos/fisiologia , Metabolismo Energético , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Lagartos/metabolismo , Miócitos Cardíacos/patologia , Estações do Ano
14.
Biomedicines ; 11(3)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36979758

RESUMO

Glioblastomas (GBMs) are notoriously difficult to treat, and the development of multiple drug resistance (MDR) is common during the course of the disease. The polyunsaturated fatty acids (PUFAs) gamma-linolenic acid (GLA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) have been reported to improve MDR in several tumors including breast, bladder, and leukaemia. However, the effects of PUFAs on GBM cell MDR are poorly understood. The present study investigated the effects of PUFAs on cellular responses to temozolomide (TMZ) in U87MG cells and the TMZ-resistant (TMZR) cells derived from U87MG. Cells were treated with PUFAs in the absence or presence of TMZ and dose-response, viable cell counting, gene expression, Western blotting, flow cytometry, gas chromatography-mass spectrometry (GCMS), and drug efflux studies were performed. The development of TMZ resistance caused an increase in ABC transporter ABCB1 and ABCC1 expression. GLA-, EPA-, and DHA-treated cells had altered fatty acid composition and accumulated lipid droplets in the cytoplasm. The most significant reduction in cell growth was seen for the U87MG and TMZR cells in the presence of EPA. GLA and EPA caused more significant effects on ABC transporter expression than DHA. GLA and EPA in combination with TMZ caused significant reductions in rhodamine 123 efflux from U87MG cells but not from TMZR cells. Overall, these findings support the notion that PUFAs can modulate ABC transporters in GBM cells.

15.
Front Physiol ; 14: 1069485, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909225

RESUMO

Introduction: Chronic hypertension is accompanied by either blood-brain barrier (BBB) leakage and autonomic dysfunction. There is no consensus on the mechanism determining increased BBB permeability within autonomic areas. While some reports suggested tight junction's breakdown, others indicated the involvement of transcytosis rather than paracellular transport changes. Interestingly, exercise training was able to restore both BBB permeability and autonomic control of the circulation. We sought now to clarify the mechanism(s) governing hypertension- and exercise-induced BBB permeability. Methods: Spontaneously hypertensive rats (SHR) and normotensive controls submitted to 4-week aerobic training (T) or sedentary protocol (S) were chronically cannulated for baseline hemodynamic and autonomic recordings and evaluation of BBB permeability. Brains were harvested for measurement of BBB function (FITC-10 kDa leakage), ultrastructural analysis of BBB constituents (transmission electron microscopy) and caveolin-1 expression (immunofluorescence). Results: In SHR-S the increased pressure, augmented sympathetic vasomotor activity, higher sympathetic and lower parasympathetic modulation of the heart and the reduced baroreflex sensitivity were accompanied by robust FITC-10kDa leakage, large increase in transcytotic vesicles number/capillary, but no change in tight junctions' density within the paraventricular nucleus of the hypothalamus, the nucleus of the solitary tract and the rostral ventrolateral medulla. SHR-T exhibited restored BBB permeability and normalized vesicles counting/capillary simultaneously with a normal autonomic modulation of heart and vessels, resting bradycardia and partial pressure reduction. Caveolin-1 expression ratified the counting of transcellular, not other cytoplasmatic vesicles. Additionally, T caused in both groups significant increases in tight junctions' extension/capillary border. Discussion: Data indicate that transcytosis, not the paracellular transport, is the primary mechanism underlying both hypertension- and exercise-induced BBB permeability changes within autonomic areas. The reduced BBB permeability contributes to normalize the autonomic control of the circulation, which suppresses pressure variability and reduces the occurrence of end-organ damage in the trained SHR. Data also disclose that hypertension does not change but exercise training strengthens the resistance of the paracellular pathway in both strains.

16.
Lipids Health Dis ; 11: 171, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23231886

RESUMO

BACKGROUND: In many types of cancer, prostaglandin E2 (PGE2) is associated with tumour related processes including proliferation, migration, angiogenesis and apoptosis. However in gliomas the role of this prostanoid is poorly understood. Here, we report on the proliferative, migratory, and apoptotic effects of PGE(1), PGE(2) and Ibuprofen (IBP) observed in the T98G human glioma cell line in vitro. METHODS: T98G human glioma cells were treated with IBP, PGE(1) or PGE(2) at varying concentrations for 24-72 hours. Cell proliferation, mitotic index and apoptotic index were determined for each treatment. Caspase-9 and caspase-3 activity was measured using fluorescent probes in live cells (FITC-LEHD-FMK and FITC-DEVD-FMK respectively). The migratory capacity of the cells was quantified using a scratch migration assay and a transwell migration assay. RESULTS: A significant decrease was seen in cell number (54%) in the presence of 50 µM IBP. Mitotic index and bromodeoxyuridine (BrdU) incorporation were also decreased 57% and 65%, respectively, by IBP. The apoptotic index was increased (167%) and the in situ activity of caspase-9 and caspase-3 was evident in IBP treated cells. The inhibition of COX activity by IBP also caused a significant inhibition of cell migration in the monolayer scratch assay (74%) and the transwell migration assay (36%). In contrast, the presence of exogenous PGE(1) or PGE(2) caused significant increases in cell number (37% PGE(1) and 45% PGE(2)). When mitotic index was measured no change was found for either PG treatment. However, the BrdU incorporation rate was significantly increased by PGE(1) (62%) and to a greater extent by PGE(2) (100%). The apoptotic index was unchanged by exogenous PGs. The addition of exogenous PGs caused an increase in cell migration in the monolayer scratch assay (43% PGE(1) and 44% PGE(2)) and the transwell migration assay (28% PGE(1) and 68% PGE(2)). CONCLUSIONS: The present study demonstrated that treatments which alter PGE(1) and PGE(2) metabolism influence the proliferative and apoptotic indices of T98G glioma cells. The migratory capacity of the cells was also significantly affected by the change in prostaglandin metabolism. Modifying PG metabolism remains an interesting target for future studies in gliomas.


Assuntos
Alprostadil , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dinoprostona , Glioma , Alprostadil/metabolismo , Alprostadil/farmacologia , Caspase 3/análise , Caspase 9/análise , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/análise , Dinoprostona/metabolismo , Dinoprostona/farmacologia , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Humanos , Ibuprofeno/farmacologia
17.
J Inorg Biochem ; 225: 111596, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34601164

RESUMO

Diruthenium(II,III) metal-metal multiply bonded paddlewheel complexes bearing non-steroidal anti-inflammatory drugs are promising anticancer metallodrugs. The [Ru2(Ibp)4Cl] (Ibp, ibuprofenate anion from HIbp ibuprofen drug), free or encapsulated, shows anticancer activity against glioblastoma (in vitro, in vivo), and against human breast and prostate cancer cells. Herein we report the interaction of [Ru2(Ibp)4Cl] and of [Ru2(Ac)4(H2O)2]PF6 (Ac, acetate) with the 4-aminopyridine (4Apy) drug. The N-ligand was capable of cleaving the paddlewheel unit with oxidation of Ru2(II,III) to Ru2(III,III)O µ-oxo core in the ibuprofen complex while the acetate complex underwent axial substitution of water by 4Apy. Carefully designed synthetic and chromatographic methods succeeded in giving the novel [Ru2O(Ibp)2(4Apy)6]Cl2 metallodrug, the first diruthenium(III,III) µ-oxo having chloride as counterion. Characterization was performed by elemental analysis, mass spectrometry, thermogravimetric analysis, electronic absorption and vibrational spectroscopies, molar conductivity and cyclic voltammetry. Kinetic studies for the µ-oxo complex (in 50:50 v/v ethanol:water) suggested an aquation/complexation equilibrium in consecutive step reactions with the exchange of the two 4Apy trans to the µ-oxo bridge by water (aquation) and the back coordination of 4Apy in excess of the N-ligand (complexation). Trypan blue assays for the novel compound showed time- and dose- dependent antiproliferative effects (at 5-50 µmol L-1) and cytotoxicity (> 20 µmol L-1), and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assays gave IC50 value of 7.6 ± 1.5 µmol L-1 (at 48 h, 1-20 µmol L-1) against U87MG human glioblastoma cells (aggressive brain glioma cancer) pointing the metallodrug as potential candidate for novel therapies in gliomas.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Ibuprofeno/análogos & derivados , Ibuprofeno/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Cinética , Rutênio/química
18.
Cell Biochem Funct ; 28(1): 15-23, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19927275

RESUMO

The present study reports the synthesis of a novel compound with the formula [Ru(2)(aGLA)4Cl] according to elemental analyses data, referred to as Ru(2)GLA. The electronic spectra of Ru(2)GLA is typical of a mixed valent diruthenium(II,III) carboxylate. Ru(2)GLA was synthesized with the aim of combining and possibly improving the anti-tumour properties of the two active components ruthenium and gamma-linolenic acid (GLA). The properties of Ru(2)GLA were tested in C6 rat glioma cells by analysing cell number, viability, lipid droplet formation, apoptosis, cell cycle distribution, mitochondrial membrane potential and reactive oxygen species. Ru(2)GLA inhibited cell proliferation in a time and concentration dependent manner. Nile Red staining suggested that Ru(2)GLA enters the cells and ICP-AES elemental analysis found an increase in ruthenium from <0.02 to 425 mg/Kg in treated cells. The sub-G1 apoptotic cell population was increased by Ru(2)GLA (22 +/- 5.2%) when analysed by FACS and this was confirmed by Hoechst staining of nuclei. Mitochondrial membrane potential was decreased in the presence of Ru(2)GLA (44 +/- 2.3%). In contrast, the cells which maintained a high mitochondrial membrane potential had an increase (18 +/- 1.5%) in reactive oxygen species generation. Both decreased mitochondrial membrane potential and increased reactive oxygen species generation may be involved in triggering apoptosis in Ru(2)GLA exposed cells. The EC(50) for Ru(2)GLA decreased with increasing time of exposure from 285 microM at 24 h, 211 microM at 48 h to 81 microM at 72 h. In conclusion, Ru(2)GLA is a novel drug with antiproliferative properties in C6 glioma cells and is a potential candidate for novel therapies in gliomas.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Glioma/tratamento farmacológico , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Rutênio/química , Ácido gama-Linolênico/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Benzimidazóis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Citometria de Fluxo , Fase G1 , Glioma/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Oxazinas/farmacologia , Ratos , Espectrofotometria Atômica , Coloração e Rotulagem
19.
J Inorg Biochem ; 205: 110984, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31927403

RESUMO

Novel formulations of diruthenium(II,III)-NSAID (NSAID, non-steroidal anti-inflammatory drug) metallodrugs encapsulated into biocompatible terpolymer-lipid nanoparticles (TPLNs) to target glioblastoma cancer were developed. The nanoformulations of Ibuprofenate (RuIbp) and Naproxenate (RuNpx) metallodrugs were synthesized and characterized. The procedure rationally designed to avoid structural changes on the coordination sphere of the [Ru2(NSAID)4]+ paddlewheel unit succeeded in giving colloidally stable and nearly spherical shaped loaded [Ru2(NSAID)4]-TPLNs with appropriate parameters (~90% loading efficiency; drug loading around 10%; particle size ~130 nm; zeta potential around - 40 mV). The maintenance of the [Ru2(NSAID)4]+ framework was confirmed by spectroscopy and mass spectrometry. The encapsulation enhanced antiproliferative effects in U87MG cells for both metallodrugs. The RuIbp-TPLNs showed efficacy also against the cisplatin chemoresistant T98G cancer cells. Lack of significant effects for the loaded-Ibuprofen-TPLNs (HIbp-TPLNs) on both types of cells supports the key role of the dimetal core in the anticancer activity of the [Ru2(NSAID)4]+ metallodrugs. The high cell viability (>70%) found for both types of cells suggests activity associated mainly to antiproliferative effects. The blank-TPLNs internalized into U87MG cell cytoplasm mostly at the first 6 h, by energy-dependent mechanism. The cell uptake of the RuIbp-TPLNs occurred during the first 24 h and it was enhanced in relation to the non-encapsulated metallodrug. The development of these novel metallodrug-loaded TPLN nanoformulations, which exhibit colloidal stability suitable for intravenous injection and enhanced drug cellular uptake, expands the perspective for diruthenium(II,III)-NSAID metallodrugs targeting brain glioblastoma cancer.


Assuntos
Anti-Inflamatórios não Esteroides , Antineoplásicos , Neoplasias Encefálicas/tratamento farmacológico , Portadores de Fármacos , Glioblastoma/tratamento farmacológico , Nanopartículas Metálicas , Rutênio , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Rutênio/química , Rutênio/farmacologia
20.
Front Nutr ; 7: 4, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32083092

RESUMO

Cancer cachexia affects about 80% of advanced cancer patients, it is linked to poor prognosis and to date, there is no efficient treatment or cure. The syndrome leads to progressive involuntary loss of muscle and fat mass induced by systemic inflammatory processes. The role of the white adipose tissue (WAT) in the onset and manifestation of cancer cachexia gained importance during the last decade. WAT wasting is not only characterized by increased lipolysis and release of free fatty acids (FFA), but in addition, owing to its high capacity to produce a variety of inflammatory factors. The aim of this study was to characterize plasma lipid profile of cachectic patients and to correlate the FA composition with circulating inflammatory markers; finally, we sought to establish whether the fatty acids released by adipocytes trigger and/or contribute to local and systemic inflammation in cachexia. The study selected 65 patients further divided into 3 groups: control (N); weight stable cancer (WSC); and cachectic cancer (CC). The plasma FA profile was significantly different among the groups and was positively correlated with pro-inflammatory cytokines expression in the CC patients. Therefore, we propose that saturated to unsaturated FFA ratio may serve as a means of detecting cachexia.

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