Network-Based Identification of Altered Stem Cell Pluripotency and Calcium Signaling Pathways in Metastatic Melanoma

Malignancy of cancer has been linked to distinct subsets of stem-like cells, the so-called cancer stem cells (CSCs), which persist during treatment and seem to lead to drug-resistant recurrence. Metastatic spread of cancer cells is one of the hallmarks of malignancy and contributes to most human melanoma-related deaths. Recently, overlapping groups of proteins and pathways were shown to regulate stem cell migration and cancer metastasis, raising the question of whether genes/proteins involved in stem cell pluripotency may have important implications when applied to the biology of cancer metastasis. Furthermore, it is well known that ion channels and receptors, particularly those responsible for calcium (Ca2+) signal generation, are critical in determining the cellular fate of stem cells (SCs). In the present study, we searched for evidence of altered stem cell pluripotency and Ca2+ signaling-related genes in the context of melanoma metastasis. We did this by using network analysis of gene expression in tissue biopsies from three different independent datasets of patients. First, we created an in silico network model (“STEMCa” interactome) showing the landscape of interactions between stem cell pluripotency and Ca2+ signaling-related genes/proteins, and demonstrated that around 51% (151 out of 294) of the genes within this model displayed significant changes of expression (False Discovery Rate (FDR), corrected p-value </p

Focussed microarray analysis of apoptosis in periodontitis and its potential pharmacological targeting by carvacrol

AbstractObjectiveThe objective of this study was to perform a landscape analysis of apoptosis-related genes/proteins and to study the differential gene expression by analysing array data from periodontitis patients and, second, to evaluate the anti-apoptotic effects of carvacrol, a monoterpenoid phenol, in vitro.DesignA gene/protein interaction network model ‘APOP’ was developed by using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) version 9.05. Differential gene expression was determined by using the limma package from R and false discovery rate (FDR). With ViaComplex software, gene expression was plotted over the network. The anti-apoptotic effect of carvacrol was tested on sorbitol-treated HaCaT cells, by using a commercial kit for caspase-3 activity.ResultsThe ‘APOP’ model characterised the landscape of interactions between apoptosis-related genes/proteins in silico. Forty-nine out of 70 genes from this model, such as CSF2RB, NFKBIE, ENDOG, CASP10 and CASP3, were differentially expressed (corrected p-value<0.05) in periodontitis samples when compared to those of healthy controls. In addition, carvacrol (0.43%) was able to inhibit the pro-apoptotic effects induced by sorbitol (0.3M), as seen by the reduction in caspase-3 activity on HaCaT cells.ConclusionOur results suggest that caspase-3 can be a target protein to inhibit periodontitis-associated apoptosis of epithelial cells and that carvacrol has therapeutic potential as an anti-apoptotic agent

Effects of Achyrocline satureioides inflorescence extracts against pathogenic intestinal bacteria : chemical characterization, in vitro tests, and in vivo evaluation

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared fromthe aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol).The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of antimicrobial activity against intestinal pathogenic bacteria greater than those observed by the antibiotic, amoxicillin, when tested against Bacillus cereus and Staphylococcus aureus. Antioxidant and antimicrobial activities of AS extracts seemed to be positively correlated with the present amount of flavonoids. These findings suggest a potential use of AS as a coadjuvant agent for treating bacterial-induced intestinal diseases with high rates of antibiotic resistance

Effects of Achyrocline satureioides

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared from the aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol). The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17 mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of antimicrobial activity against intestinal pathogenic bacteria greater than those observed by the antibiotic, amoxicillin, when tested against Bacillus cereus and Staphylococcus aureus. Antioxidant and antimicrobial activities of AS extracts seemed to be positively correlated with the present amount of flavonoids. These findings suggest a potential use of AS as a coadjuvant agent for treating bacterial-induced intestinal diseases with high rates of antibiotic resistance

Do ambiente aos genes : o uso de ferramentas bioinformáticas na procura de um mínimo denominador molecular e celular comum no espectro autista

O autismo pode ser definido como um transtorno associado ao desenvolvimento e caracterizado por prejuízo na interação social, na comunicação e no comportamento. Sua etiologia ainda é pouco conhecida, existindo alterações no desenvolvimento encefálico durante a embriogênese e na vida pós-natal. Sugere-se uma complexa interface entre fatores genéticos e ambientais. Existem provas que mostram uma desregulação do controle da homeostase e redes neuronais por parte de células astrogliais, ativação da microglia e respostas neuroinflamatórias no encéfalo de pacientes autistas até a idade adulta, representando uma alteração celular comum dentro do espectro autista (ASD). A grande variabilidade dos sintomas encontrados nos pacientes torna extremamente difícil a identificação de cascatas de sinalização comuns associadas com a patologia tipicamente autista, críticas para a procura de marcadores periféricos de diagnóstico e para identificar novos alvos terapêuticos. Neste trabalho, (i) caracterizamos a natureza multifatorial do autismo, funções moleculares, componentes celulares e processos biológicos associados, (ii) mostramos que RAC1, em particular, e a família das RHO GTPases, em geral, poderiam ter um papel crítico nos eventos neuropatológicos associados ao autismo, sendo o cálcio (Ca2+) a molécula mais central na complexa interface entre fatores genéticos e ambientais e (iii) sugerimos um modelo baseado na ativação da enzima α-secretase, mediada por receptores de glutamato (NMDARs), influxo de Ca2+, ativação de Erk e adaptação da mitocôndria a apoptose, como cascata de sinalização bioquímica que poderia explicar o aumento do volume encefálico e a falha da conectividade cerebral observada em crianças autistas e que, potencialmente, poderia ser tratada com derivados de magnésio e rapamicina.Autism is a neurodevelopmental disorder characterized by specific activity patterns and aberrant social interaction and communication. Even though its etiology is not well understood, a number of neuropathological events during central nervous system development, in childhood and adolescence, have already been described. A complex interface between genetic and environmental factors is also suggested to account for the disorder. Evidence shows a deregulation of the homeostatic control of neuronal networks by astroglia, microglial activation, and neuroinflammation; changes that persist even until adulthood and may represent a common cellular disturbance in autism spectrum disorders (ASD). The great variability of symptoms found in the patients makes a difficult challenge the identification of disrupted signaling pathways associated to ASD, which is critical to identify potentially novel biomarkers for diagnoses as well as novel therapeutic targets. In the present study, (i) we characterized the multifactorial nature of autism, molecular functions, cellular components, and biological processes associated to the disorder, (ii) we showed RAC1, in particular, and the RHO family of GTPases, in general, could play a critical role in the neuropathological events associated with autism, with calcium (Ca2+) as the most central component in interface between genetic and environmental factors, and (iii) we proposed a model of glutamate receptors (NMDARs)-mediated Erk activation of α-secretase activity and mitochondrial adaptation to apoptosis that may explain the early brain overgrowth and disruption of synaptic plasticity and connectome in autistic children, which could potentially be targeted by magnesium-based drugs and rapamycin

Do ambiente aos genes : o uso de ferramentas bioinformáticas na procura de um mínimo denominador molecular e celular comum no espectro autista

O autismo pode ser definido como um transtorno associado ao desenvolvimento e caracterizado por prejuízo na interação social, na comunicação e no comportamento. Sua etiologia ainda é pouco conhecida, existindo alterações no desenvolvimento encefálico durante a embriogênese e na vida pós-natal. Sugere-se uma complexa interface entre fatores genéticos e ambientais. Existem provas que mostram uma desregulação do controle da homeostase e redes neuronais por parte de células astrogliais, ativação da microglia e respostas neuroinflamatórias no encéfalo de pacientes autistas até a idade adulta, representando uma alteração celular comum dentro do espectro autista (ASD). A grande variabilidade dos sintomas encontrados nos pacientes torna extremamente difícil a identificação de cascatas de sinalização comuns associadas com a patologia tipicamente autista, críticas para a procura de marcadores periféricos de diagnóstico e para identificar novos alvos terapêuticos. Neste trabalho, (i) caracterizamos a natureza multifatorial do autismo, funções moleculares, componentes celulares e processos biológicos associados, (ii) mostramos que RAC1, em particular, e a família das RHO GTPases, em geral, poderiam ter um papel crítico nos eventos neuropatológicos associados ao autismo, sendo o cálcio (Ca2+) a molécula mais central na complexa interface entre fatores genéticos e ambientais e (iii) sugerimos um modelo baseado na ativação da enzima α-secretase, mediada por receptores de glutamato (NMDARs), influxo de Ca2+, ativação de Erk e adaptação da mitocôndria a apoptose, como cascata de sinalização bioquímica que poderia explicar o aumento do volume encefálico e a falha da conectividade cerebral observada em crianças autistas e que, potencialmente, poderia ser tratada com derivados de magnésio e rapamicina.Autism is a neurodevelopmental disorder characterized by specific activity patterns and aberrant social interaction and communication. Even though its etiology is not well understood, a number of neuropathological events during central nervous system development, in childhood and adolescence, have already been described. A complex interface between genetic and environmental factors is also suggested to account for the disorder. Evidence shows a deregulation of the homeostatic control of neuronal networks by astroglia, microglial activation, and neuroinflammation; changes that persist even until adulthood and may represent a common cellular disturbance in autism spectrum disorders (ASD). The great variability of symptoms found in the patients makes a difficult challenge the identification of disrupted signaling pathways associated to ASD, which is critical to identify potentially novel biomarkers for diagnoses as well as novel therapeutic targets. In the present study, (i) we characterized the multifactorial nature of autism, molecular functions, cellular components, and biological processes associated to the disorder, (ii) we showed RAC1, in particular, and the RHO family of GTPases, in general, could play a critical role in the neuropathological events associated with autism, with calcium (Ca2+) as the most central component in interface between genetic and environmental factors, and (iii) we proposed a model of glutamate receptors (NMDARs)-mediated Erk activation of α-secretase activity and mitochondrial adaptation to apoptosis that may explain the early brain overgrowth and disruption of synaptic plasticity and connectome in autistic children, which could potentially be targeted by magnesium-based drugs and rapamycin

Calcium signalling toolkits in astrocytes and spatio-temporal progression of Alzheimer's disease.

Pathological remodelling of astroglia represents an important component of the pathogenesis of Alzheimer's disease (AD). In AD astrocytes undergo both atrophy and reactivity; which may be specific for different stages of the disease evolution. Astroglial reactivity represents the generic defensive mechanism, and inhibition of astrogliotic response exacerbates b-amyloid pathology associated with AD. In animal models of AD astroglial reactivity is different in different brain regions, and the deficits of reactive response observed in entorhinal and prefrontal cortices may be linked to their vulnerability to AD progression. Reactive astrogliosis is linked to astroglial Ca2+ signalling, this latter being widely regarded as a mechanism of astroglial excitability. The AD pathology evolving in animal models as well as acute or chronic exposure to -amyloid induce pathological remodelling of Ca2+ signalling toolkit in astrocytes. This remodelling modifies astroglial Ca2+ signalling and may be linked to cellular mechanisms of AD pathogenesis