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Inflammation with expression of interleukin 6 (IL-6) in the central nervous system (CNS) occurs in several neurodegenerative/neuroinflammatory conditions and may cause neurochemical changes to endogenous neuroprotective systems. Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP) are two neuropeptides with well-established protective and anti-inflammatory properties. Yet, whether PACAP and VIP levels are altered in mice with CNS-restricted, astrocyte-targeted production of IL-6 (GFAP-IL6) remains unknown. In this study, PACAP/VIP levels were assessed in the brain of GFAP-IL6 mice. In addition, we utilised bi-genic GFAP-IL6 mice carrying the human sgp130-Fc transgene (termed GFAP-IL6/sgp130Fc mice) to determine whether trans-signalling inhibition rescued PACAP/VIP changes in the CNS. Transcripts and protein levels of PACAP and VIP, as well as their receptors PAC1, VPAC1 and VPAC2, were significantly increased in the cerebrum and cerebellum of GFAP-IL6 mice vs. wild type (WT) littermates. These results were paralleled by a robust activation of the JAK/STAT3, NF-κB and ERK1/2MAPK pathways in GFAP-IL6 mice. In contrast, co-expression of sgp130Fc in GFAP-IL6/sgp130Fc mice reduced VIP expression and activation of STAT3 and NF-κB pathways, but it failed to rescue PACAP, PACAP/VIP receptors and Erk1/2MAPK phosphorylation. We conclude that forced expression of IL-6 in astrocytes induces the activation of the PACAP/VIP neuropeptide system in the brain, which is only partly modulated upon IL-6 trans-signalling inhibition. Increased expression of PACAP/VIP neuropeptides and receptors may represent a homeostatic response of the CNS to an uncontrolled IL-6 synthesis and its neuroinflammatory consequences.
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Encéfalo , Interleucina-6 , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Transdução de Sinais , Peptídeo Intestinal Vasoativo , Animais , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Interleucina-6/metabolismo , Interleucina-6/genética , Camundongos , Peptídeo Intestinal Vasoativo/metabolismo , Peptídeo Intestinal Vasoativo/genética , Encéfalo/metabolismo , Astrócitos/metabolismo , Humanos , Camundongos Transgênicos , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/genética , Sistema Nervoso Central/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Masculino , Camundongos Endogâmicos C57BLRESUMO
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system with a strong neuroinflammatory component. Current treatments principally target the immune system but fail to preserve long-term myelin health and do not prevent neurological decline. Studies over the past two decades have shown that the structurally related neuropeptides VIP and PACAP (vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide, respectively) exhibit pronounced anti-inflammatory activities and reduce clinical symptoms in MS disease models, largely via actions on their bivalent VIP receptor type 1 and 2. Here, using the cuprizone demyelination model, we demonstrate that PACAP and VIP, and strikingly the PACAP-selective receptor PAC1 agonist maxadilan, prevented locomotor deficits in the horizontal ladder and open field tests. Moreover, only PACAP and maxadilan were able to prevent myelin deterioration, as assessed by a reduction in the expression of the myelin markers proteolipid protein 1, oligodendrocyte transcription factor 2, quaking-7 (APC) and Luxol Fast Blue staining. Furthermore, PACAP and maxadilan (but not VIP), prevented striatal synaptic loss and diminished astrocyte and microglial activation in the corpus callosum of cuprizone-fed mice. In vitro, PACAP or maxadilan prevented lipopolysaccharide (LPS)-induced polarisation of primary astrocytes at 12-24 h, an effect that was not seen with maxadilan in LPS-stimulated microglia. Taken together, our data demonstrates for the first time that PAC1 agonists provide distinctive protective effects against white matter deterioration, neuroinflammation and consequent locomotor dysfunctions in the cuprizone model. The results indicate that targeting the PAC1 receptor may provide a path to treat myelin-related diseases in humans.
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Cuprizona , Doenças Desmielinizantes , Bainha de Mielina , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Animais , Masculino , Camundongos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Modelos Animais de Doenças , Proteínas de Insetos , Locomoção/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Peptídeo Intestinal Vasoativo/farmacologiaRESUMO
Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are two neuroprotective and anti-inflammatory molecules of the central nervous system (CNS). Both bind to three G protein-coupled receptors, namely PAC1, VPAC1 and VPAC2, to elicit their beneficial effects in various CNS diseases, including multiple sclerosis (MS). In this study, we assessed the expression and distribution of PACAP/VIP receptors in the normal-appearing white matter (NAWM) of MS donors with a clinical history of either relapsing-remitting MS (RRMS), primary MS (PPMS), secondary progressive MS (SPMS) or in aged-matched non-MS controls. Gene expression studies revealed MS-subtype specific changes in PACAP and VIP and in the receptors' levels in the NAWM, which were partly corroborated by immunohistochemical analyses. Most PAC1 immunoreactivity was restricted to myelin-producing cells, whereas VPAC1 reactivity was diffused within the neuropil and in axonal bundles, and VPAC2 in small vessel walls. Within and around lesioned areas, glial cells were the predominant populations showing reactivity for the different PACAP/VIP receptors, with distinctive patterns across MS subtypes. Together, these data identify the differential expression patterns of PACAP/VIP receptors among the different MS clinical entities. These results may offer opportunities for the development of personalized therapeutic approaches to treating MS and/or other demyelinating disorders.
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Esclerose Múltipla , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Peptídeo Intestinal Vasoativo , Substância Branca , Humanos , Substância Branca/metabolismo , Substância Branca/patologia , Masculino , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Pessoa de Meia-Idade , Feminino , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Adulto , Peptídeo Intestinal Vasoativo/metabolismo , Receptores Tipo II de Peptídeo Intestinal Vasoativo/metabolismo , Receptores Tipo II de Peptídeo Intestinal Vasoativo/genética , Idoso , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/metabolismo , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/genética , Autopsia , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Esclerose Múltipla Recidivante-Remitente/metabolismo , Esclerose Múltipla Recidivante-Remitente/patologiaRESUMO
Pleural mesothelioma (PM) is a highly aggressive tumor that is caused by asbestos exposure and lacks effective therapeutic regimens. Current procedures for PM diagnosis are invasive and can take a long time to reach a definitive result. Small extracellular vesicles (sEVs) have been identified as important communicators between tumor cells and their microenvironment via their cargo including circular RNAs (circRNAs). CircRNAs are thermodynamically stable, highly conserved, and have been found to be dysregulated in cancer. This study aimed to identify potential biomarkers for PM diagnosis by investigating the expression of specific circRNA gene pattern (hsa_circ_0007386) in cells and sEVs using digital polymerase chain reaction (dPCR). For this reason, 5 PM, 14 non-PM, and one normal mesothelial cell line were cultured. The sEV was isolated from the cells using the gold standard ultracentrifuge method. The RNA was extracted from both cells and sEVs, cDNA was synthesized, and dPCR was run. Results showed that hsa_circ_0007386 was significantly overexpressed in PM cell lines and sEVs compared to non-PM and normal mesothelial cell lines (p < 0.0001). The upregulation of hsa_circ_0007386 in PM highlights its potential as a diagnostic biomarker. This study underscores the importance and potential of circRNAs and sEVs as cancer diagnostic tools.
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Biomarcadores Tumorais , Vesículas Extracelulares , Mesotelioma , RNA Circular , Humanos , RNA Circular/genética , RNA Circular/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Mesotelioma/genética , Mesotelioma/diagnóstico , Linhagem Celular Tumoral , Neoplasias Pleurais/genética , Neoplasias Pleurais/diagnóstico , Regulação Neoplásica da Expressão Gênica , Mesotelioma Maligno/genética , Mesotelioma Maligno/diagnósticoRESUMO
Stem cells are ubiquitously found in various tissues and organs in the body, and underpin the body's ability to repair itself following injury or disease initiation, though repair can sometimes be compromised. Understanding how stem cells are produced, and functional signaling systems between different niches is critical to understanding the potential use of stem cells in regenerative medicine. In this context, this review considers kynurenine pathway (KP) metabolism in multipotent adult progenitor cells, embryonic, haematopoietic, neural, cancer, cardiac and induced pluripotent stem cells, endothelial progenitor cells, and mesenchymal stromal cells. The KP is the major enzymatic pathway for sequentially catabolising the essential amino acid tryptophan (TRP), resulting in key metabolites including kynurenine, kynurenic acid, and quinolinic acid (QUIN). QUIN metabolism transitions into the adjoining de novo pathway for nicotinamide adenine dinucleotide (NAD) production, a critical cofactor in many fundamental cellular biochemical pathways. How stem cells uptake and utilise TRP varies between different species and stem cell types, because of their expression of transporters and responses to inflammatory cytokines. Several KP metabolites are physiologically active, with either beneficial or detrimental outcomes, and evidence of this is presented relating to several stem cell types, which is important as they may exert a significant impact on surrounding differentiated cells, particularly if they metabolise or secrete metabolites differently. Interferon-gamma (IFN-γ) in mesenchymal stromal cells, for instance, highly upregulates rate-limiting enzyme indoleamine-2,3-dioxygenase (IDO-1), initiating TRP depletion and production of metabolites including kynurenine/kynurenic acid, known agonists of the Aryl hydrocarbon receptor (AhR) transcription factor. AhR transcriptionally regulates an immunosuppressive phenotype, making them attractive for regenerative therapy. We also draw attention to important gaps in knowledge for future studies, which will underpin future application for stem cell-based cellular therapies or optimising drugs which can modulate the KP in innate stem cell populations, for disease treatment.
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The habenular complex is a diencephalic structure divided into the medial and lateral divisions that lie within the epithalamus of most vertebrates. This brain structure, whose activities are mainly regulated via inputs/outputs from and to the stria medullaris and the fasciculus retroflexus, plays a significant role in the modulation of anti-reward behaviors in both the rodent and human brain. Such anti-reward circuits are regulated by dopaminergic and serotonergic projections with several other subcortical and cortical regions; therefore, it is plausible that impairment to this key subcortical structure or its connections contributes to the pathogenesis of affective disorders. Current literature reveals the existence of structural changes in the habenula complex in individuals afflicted by such disorders; however, there is a need for more comprehensive investigations to elucidate the underlying neuroanatomical connections that underpin disease development. In this review article, we aim to provide a comprehensive view of the neuroanatomical differences between the rodent and human habenular complex, the main circuitries, and provide an update on the emerging roles of this understudied subcortical structure in the control of affective behaviors, with special emphasis to morbid conditions of the affective sphere.
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Multiple sclerosis (MS) is an immune-mediated disorder characterized by focal demyelination and chronic inflammation of the central nervous system (CNS). Although the exact etiology is unclear, mounting evidence indicates that endoplasmic reticulum (ER) stress represents a key event in disease pathogenesis. Pituitary adenylate cyclase-activating peptide (PACAP) and vasoactive intestinal peptide (VIP) are two structurally related neuropeptides that are abundant in the CNS and are known to exert neuroprotective and immune modulatory roles. Activation of this endogenous neuropeptide system may interfere with ER stress processes to promote glial cell survival and myelin self-repair. However, the potential crosstalk between the PACAP/VIP system and ER stress remains elusive. In this review, we aim to discuss how these peptides ameliorate ER stress in the CNS, with a focus on MS pathology. Our goal is to emphasize the importance of this potential interaction to aid in the identification of novel therapeutic targets for the treatment of MS and other demyelinating disorders.
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Esclerose Múltipla , Peptídeo Intestinal Vasoativo , Humanos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Peptídeo Intestinal Vasoativo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Transdução de Sinais/fisiologia , Estresse do Retículo EndoplasmáticoRESUMO
Multiple sclerosis is a disease that concerns a growing number of people, especially females. There are different interventions proposed for this population, and physical activity is one of them. A proper and well-structured physical activity program can be a cheap, feasible, and practical instrument to help this population improve their quality of life. Consequently, the present study aimed to analyze, through an umbrella review, published articles to evaluate the protocols and the effect of intervention on different types of multiple sclerosis and eventually to propose a standardized intervention for this population. Systematic reviews and meta-analyses of randomized controlled trials on multiple sclerosis and physical activity effects were searched for on the electronic databases PubMed, Web of Science, and Scopus up to 22 December 2022. The quality of the studies included was determined and the results were narratively analyzed. The included studies present heterogeneity in the population, in the study design and protocols, and in the outcomes evaluated. Most of the studies detected positive outcomes on the physical function of people with multiple sclerosis. This study highlights the necessity of future studies on a population with similar characteristics, adopting similar protocols to evaluate their feasibility and validity to make physical intervention prescribed as a medicine.
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Previous evidence shows that rapid changes occur in the brain following spinal cord injury (SCI). Here, we interrogated the expression of the neuropeptides pituitary adenylyl cyclase-activating peptide (PACAP), vasoactive intestinal peptides (VIP), and their binding receptors in the rat brain 24 h following SCI. Female Sprague-Dawley rats underwent thoracic laminectomy; half of the rats received a mild contusion injury at the level of the T10 vertebrate (SCI group); the other half underwent sham surgery (sham group). Twenty-four hours post-surgery, the hypothalamus, thalamus, amygdala, hippocampus (dorsal and ventral), prefrontal cortex, and periaqueductal gray were collected. PACAP, VIP, PAC1, VPAC1, and VPAC2 mRNA and protein levels were measured by real-time quantitative polymerase chain reaction and Western blot. In SCI rats, PACAP expression was increased in the hypothalamus (104-141% vs sham) and amygdala (138-350%), but downregulated in the thalamus (35-95%) and periaqueductal gray (58-68%). VIP expression was increased only in the thalamus (175-385%), with a reduction in the amygdala (51-68%), hippocampus (40-75%), and periaqueductal gray (74-76%). The expression of the PAC1 receptor was the least disturbed by SCI, with decrease expression in the ventral hippocampus (63-68%) only. The expression levels of VPAC1 and VPAC2 receptors were globally reduced, with more prominent reductions of VPAC1 vs VPAC2 in the amygdala (21-70%) and ventral hippocampus (72-75%). In addition, VPAC1 downregulation also extended to the dorsal hippocampus (69-70%). These findings demonstrate that as early as 24 h post-SCI, there are region-specific disruptions of PACAP, VIP, and related receptor transcript and protein levels in supraspinal regions controlling higher cognitive functions.
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Receptores do Hormônio Hipofisário , Traumatismos da Medula Espinal , Feminino , Ratos , Animais , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Ratos Sprague-Dawley , Receptores do Hormônio Hipofisário/genética , Receptores do Hormônio Hipofisário/metabolismo , Peptídeo Intestinal Vasoativo/genética , Peptídeo Intestinal Vasoativo/metabolismo , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/genética , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/metabolismo , Receptores Tipo II de Peptídeo Intestinal Vasoativo/genética , Receptores Tipo II de Peptídeo Intestinal Vasoativo/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Traumatismos da Medula Espinal/metabolismo , Encéfalo/metabolismoRESUMO
Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of the most common and severe manifestations of lupus; however, its pathogenesis is still poorly understood. While there is sparse evidence suggesting that the ongoing autoimmunity may trigger pathogenic changes to the central nervous system (CNS) microvasculature, culminating in inflammatory/ischemic damage, further evidence is still needed. In this study, we used the spontaneous mouse model of SLE (NZBWF1 mice) to investigate the expression of genes and proteins associated with endothelial (dys)function: tissue and urokinase plasminogen activators (tPA and uPA), intercellular and vascular adhesion molecules 1 (ICAM-1 and VCAM-1), brain derived neurotrophic factor (BDNF), endothelial nitric oxide synthase (eNOS) and Krüppel-like factor 4 (KLF4) and neuroprotection/immune modulation: pituitary adenylate cyclase-activating peptide (PACAP), vasoactive intestinal peptide (VIP), PACAP receptor (PAC1), VIP receptors 1 and 2 (VPAC1 and VPAC2). Analyses were carried out both in the hippocampus and striatum of SLE mice of two different age groups (2 and 7 months old), since age correlates with disease severity. In the hippocampus, we identified a gene/protein expression profile indicative of mild endothelial dysfunction, which increased in severity in aged SLE mice. These alterations were paralleled by moderate alterations in the expression of VIP, PACAP and related receptors. In contrast, we report a robust upregulation of endothelial activation markers in the striatum of both young and aged mice, concurrent with significant induction of the VIP/PACAP system. These data identify molecular signatures of endothelial alterations in the hippocampus and striatum of NZBWF1 mice, which are accompanied by a heightened expression of endogenous protective/immune-modulatory neuropeptides. Collectively, our results support the idea that NPSLE may cause alterations of the CNS micro-vascular compartment that cannot be effectively counteracted by the endogenous activity of the neuropeptides PACAP and VIP.
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Lúpus Eritematoso Sistêmico , Peptídeo Intestinal Vasoativo , Camundongos , Animais , Peptídeo Intestinal Vasoativo/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo , Receptores Tipo II de Peptídeo Intestinal VasoativoRESUMO
L-Azetidine-2-carboxylic acid (AZE) is a non-protein amino acid that shares structural similarities with its proteogenic L-proline amino acid counterpart. For this reason, AZE can be misincorporated in place of L-proline, contributing to AZE toxicity. In previous work, we have shown that AZE induces both polarization and apoptosis in BV2 microglial cells. However, it is still unknown if these detrimental effects involve endoplasmic reticulum (ER) stress and whether L-proline co-administration prevents AZE-induced damage to microglia. Here, we investigated the gene expression of ER stress markers in BV2 microglial cells treated with AZE alone (1000 µM), or co-treated with L-proline (50 µM), for 6 or 24 h. AZE reduced cell viability, nitric oxide (NO) secretion and caused a robust activation of the unfolded protein response (UPR) genes (ATF4, ATF6, ERN1, PERK, XBP1, DDIT3, GADD34). These results were confirmed by immunofluorescence in BV2 and primary microglial cultures. AZE also altered the expression of microglial M1 phenotypic markers (increased IL-6, decreased CD206 and TREM2 expression). These effects were almost completely prevented upon L-proline co-administration. Finally, triple/quadrupole mass spectrometry demonstrated a robust increase in AZE-bound proteins after AZE treatment, which was reduced by 84% upon L-proline co-supplementation. This study identified ER stress as a pathogenic mechanism for AZE-induced microglial activation and death, which is reversed by co-administration of L-proline.
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Microglia , Prolina , Prolina/farmacologia , Prolina/química , Ácido Azetidinocarboxílico/farmacologia , Ácido Azetidinocarboxílico/química , Aminoácidos , Estresse do Retículo EndoplasmáticoRESUMO
Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system (CNS) whose aetiology is only partly understood. Investigating the intricate transcriptional changes occurring in MS brains is critical to unravel novel pathogenic mechanisms and therapeutic targets. Unfortunately, this process is often hindered by the difficulty in retrieving an adequate number of samples. However, by merging data from publicly available datasets, it is possible to identify alterations in gene expression profiles and regulatory pathways that were previously overlooked. Here, we merged microarray gene expression profiles obtained from CNS white matter samples taken from MS donors to identify novel differentially expressed genes (DEGs) linked with MS. Data from three independent datasets (GSE38010, GSE32915, and GSE108000) were combined and used to detect novel DEGs using the Stouffer's Z-score method. Corresponding regulatory pathways were analysed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway databases. Finally, top up- and down-regulated transcripts were validated by real-time quantitative PCR (qPCR) using an independent set of white matter tissue samples obtained from MS donors with different disease subtypes. There were a total of 1446 DEGs, of which 742 were up-regulated and 704 genes were down-regulated. DEGs were associated with several myelin-related pathways and protein metabolism pathways. Validation studies of selected top up- or down-regulated genes highlighted MS subtype-specific differences in the expression of some of the identified genes, underlining a more complex scenario of white matter pathology amongst people afflicted by this devastating disease.
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Esclerose Múltipla , Humanos , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Perfilação da Expressão Gênica/métodos , Encéfalo/metabolismo , Análise em Microsséries , Sistema Nervoso Central/metabolismo , Biologia Computacional/métodos , Redes Reguladoras de GenesRESUMO
Physiological aging triggers a cascade of negative effects on the human body and the human joint is only one of the several compartments affected by this irreversible and natural process. Osteoarthritis and cartilage degeneration can cause pain and disability; therefore, identifying the molecular processes underlying these phenomena and the biomarkers produced during physical activity is of critical importance. In the present review, the main goal was to identify and discuss the articular cartilage biomarkers analyzed in studies in which physical or sports activities were adopted and eventually to propose a standard operating procedure for the assessment. Articles collected from Pubmed, Web of Science, and Scopus were scrutinized to detect reliable cartilage biomarkers. The principal articular cartilage biomarkers detected in these studies were cartilage oligomeric matrix protein, matrix metalloproteinases, interleukins, and carboxy-terminal telopeptide. The articular cartilage biomarkers identified in this scoping review may aid in a better comprehension of where research on the topic is heading and offer a viable instrument for streamlining investigations on cartilage biomarker discovery.
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Cartilagem Articular , Osteoartrite , Humanos , Envelhecimento/metabolismo , Envelhecimento/patologia , Biomarcadores/metabolismo , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Exercício Físico/fisiologia , Osteoartrite/metabolismoRESUMO
Systemic administration of rotenone replicates several pathogenic and behavioural features of Parkinson's disease (PD), some of which cannot be explained by deficits of the nigrostriatal pathway. In this study, we provide a comprehensive analysis of several neurochemical alterations triggered by systemic rotenone administration in the CNS of C57BL/6 mice. Mice injected with either 1, 3 or 10 mg/kg rotenone daily via intraperitoneal route for 21 days were assessed weekly for changes in locomotor and exploratory behaviour. Rotenone treatment caused significant locomotor and exploratory impairment at dosages of 3 or 10 mg/kg. Molecular analyses showed reductions of both TH and DAT expression in the midbrain, striatum and spinal cord, accompanied by altered expression of dopamine receptors and brain-derived neurotrophic factor (BDNF). Rotenone also triggered midbrain-restricted inflammatory responses with heightened expression of glial markers, which was not seen in extra-nigral regions. However, widespread alterations of mitochondrial function and increased signatures of oxidative stress were identified in both nigral and extra-nigral regions, along with disruptions of neuroprotective peptides, such as pituitary adenylate cyclase-activating polypeptide (PACAP), vasoactive intestinal peptide (VIP) and activity-dependent neuroprotective protein (ADNP). Altogether, this study shows that systemic rotenone intoxication, similarly to PD, causes a series of neurochemical alterations that extend at multiple CNS levels, reinforcing the suitability of this pre-clinical model for the study extra-nigral defects of PD.
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L-Azetidine-2-carboxylic acid (AZE) is a toxic non-protein coding amino acid (npAA) that is highly abundant in sugar and table beets. Due to its structural similarity with the amino acid L-proline, AZE can evade the editing process during protein assembly in eukaryotic cells and be misincorporated into L-proline-rich proteins, potentially causing protein misfolding and other detrimental effects to cells. In this study, we sought to determine if AZE treatment triggered pro-inflammatory and pro-apoptotic responses in BV2 microglial cells. BV2 microglial cells exposed to AZE at increasing concentrations (0−2000 µM) at 0, 3, 6, 12 and 24 h were assayed for cell viability (MTT) and nitric oxide release (Griess assay). Annexin V-FITC/propidium iodide (PI) staining was used to assess apoptosis. Real-time qPCR, Western blot and immunocytochemistry were used to interrogate relevant pro- and anti-inflammatory and other molecular targets of cell survival response. AZE (at concentrations > 1000 µM) significantly reduced cell viability, increased BAX/Bcl2 ratio and caused cell death. Results were mirrored by a robust increase in nitric oxide release, percentage of activated/polarised cells and expression of pro-inflammatory markers (IL-1ß, IL-6, NOS2, CD68 and MHC-2a). Additionally, we found that AZE induced the expression of the extracellular matrix degrading enzyme matrix metalloproteinase 9 (MMP-9) and brain derived neurotrophic factor (BDNF), two critical regulators of microglial motility and structural plasticity. Collectively, these data indicate that AZE-induced toxicity is associated with increased pro-inflammatory activity and reduced survival in BV2 microglia. This evidence may prompt for an increased monitoring of AZE consumption by humans.
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Levels of the enzyme autotaxin (ATX) are elevated in synovial ï¬uid and plasma of osteoarthritic patients, correlating positively with radiographic and symptomatic severity of the disease. Therefore, ATX is studied as potential marker for the progression of osteoarthritis (OA), whereas the chondrocyte-secreted glycoprotein Lubricin has chondroprotective properties. The aim of this study was to evaluate the expression of ATX and Lubricin in healthy and mild OA rat articular cartilage of femur, tibia and patella, and to analyse the effect of a protocol of moderate physical activity on their expressions. Mild OA resulted from anterior cruciate ligament transection and rats exercised on a treadmill for 12 weeks. Computerized staining intensity of immunostaining was used to evaluate ATX and Lubricin expressions. Higher expressions of ATX were found in femur and tibia of OA rats, suggesting that this molecule could participate in the progression of the disease, although not involved in the patella. In the femur, physical activity performed by OA rats was able to lower ATX expression, encouraging the evidence that joint movement is beneficial for the cartilage, although no significant differences in Lubricin expression were detected in femur, tibia and patella. This evidence might shade some light about the role of ATX, Lubricin and physical exercise in OA progression.
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Cartilagem Articular , Glicoproteínas/análise , Osteoartrite , Diester Fosfórico Hidrolases/análise , Animais , Ligamento Cruzado Anterior/metabolismo , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Glicoproteínas/metabolismo , Osteoartrite/metabolismo , RatosRESUMO
Huntington's disease (HD) is a rare, hereditary, and progressive neurodegenerative disease, characterized by involuntary choreatic movements with cognitive and behavioral disturbances. In order to mitigate impairments in motor function, physical exercise was integrated in HD rehabilitative interventions, showing to be a powerful tool to ameliorate the quality of life of HD-affected patients. This review aims to describe the effects of physical exercise on HD-related skeletal muscle disorders in both murine and human models. We performed a literature search using PubMed, Scopus, and Web of Science databases on the role of physical activity in mouse models of HD and human patients. Fifteen publications fulfilled the criteria and were included in the review. Studies performed on mouse models showed a controversial role played by exercise, whereas in HD-affected patients, physical activity appeared to have positive effects on gait, motor function, UHDMRS scale, cognitive function, quality of life, postural stability, total body mass, fatty acid oxidative capacity, and VO2 max. Physical activity seems to be feasible, safe, and effective for HD patients. However, further studies with longer follow-up and larger cohorts of patients will be needed to draw firm conclusions on the positive effects of exercise for HD patients.
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Multiple sclerosis (MS) is a chronic neuroinflammatory and demyelinating disease of the central nervous system (CNS), characterised by the infiltration of peripheral immune cells, multifocal white-matter lesions, and neurodegeneration. In recent years, microglia have emerged as key contributors to MS pathology, acting as scavengers of toxic myelin/cell debris and modulating the inflammatory microenvironment to promote myelin repair. In this review, we explore the role of two neuropeptides, pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP), as important regulators of microglial functioning during demyelination, myelin phagocytosis, and remyelination, emphasising the potential of these neuropeptides as therapeutic targets for the treatment of MS.
Assuntos
Esclerose Múltipla , Peptídeo Intestinal Vasoativo , Humanos , Microglia , Polipeptídeo Hipofisário Ativador de Adenilato CiclaseRESUMO
Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are two widely expressed neuropeptides with important immunomodulatory and neuroprotective properties in the central nervous system (CNS). Both VIP and PACAP have been implicated in several neurological diseases and have shown favourable effects in different animal models of multiple sclerosis (MS). MS is a chronic inflammatory and neurodegenerative disease of the CNS affecting over 2.5 million people worldwide. The disease is characterised by extensive neuroinflammation, demyelination and axonal loss. Currently, there is no cure for MS, with treatment options only displaying partial efficacy. Importantly, epidemiological studies in the MS population have demonstrated that there is a high incidence of neurological and psychological comorbidities such as depression, anxiety, epilepsy and stroke among afflicted people. Hence, given the widespread protective effects of the VIP/PACAP system in the CNS, this review will aim at exploring the beneficial roles of VIP and PACAP in ameliorating some of the most common neurological comorbidities associated with MS. The final scope of the review is to put more emphasis on how targeting the VIP/PACAP system may be an effective therapeutic strategy to modify MS disease course and its associated comorbidities.