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1.
Cells ; 13(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38727306

RESUMO

Parkinson's disease (PD) is recognized as the second most prevalent primary chronic neurodegenerative disorder of the central nervous system. Clinically, PD is characterized as a movement disorder, exhibiting an incidence and mortality rate that is increasing faster than any other neurological condition. In recent years, there has been a growing interest concerning the role of the gut microbiota in the etiology and pathophysiology of PD. The establishment of a brain-gut microbiota axis is now real, with evidence denoting a bidirectional communication between the brain and the gut microbiota through metabolic, immune, neuronal, and endocrine mechanisms and pathways. Among these, the vagus nerve represents the most direct form of communication between the brain and the gut. Given the potential interactions between bacteria and drugs, it has been observed that the therapies for PD can have an impact on the composition of the microbiota. Therefore, in the scope of the present review, we will discuss the current understanding of gut microbiota on PD and whether this may be a new paradigm for treating this devastating disease.


Assuntos
Eixo Encéfalo-Intestino , Encéfalo , Microbioma Gastrointestinal , Doença de Parkinson , Humanos , Doença de Parkinson/microbiologia , Doença de Parkinson/terapia , Encéfalo/microbiologia , Encéfalo/patologia , Eixo Encéfalo-Intestino/fisiologia , Animais
2.
Mol Psychiatry ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454085

RESUMO

Adult cytogenesis, the continuous generation of newly-born neurons (neurogenesis) and glial cells (gliogenesis) throughout life, is highly impaired in several neuropsychiatric disorders, such as Major Depressive Disorder (MDD), impacting negatively on cognitive and emotional domains. Despite playing a critical role in brain homeostasis, the importance of gliogenesis has been overlooked, both in healthy and diseased states. To examine the role of newly formed glia, we transplanted Glial Restricted Precursors (GRPs) into the adult hippocampal dentate gyrus (DG), or injected their secreted factors (secretome), into a previously validated transgenic GFAP-tk rat line, in which cytogenesis is transiently compromised. We explored the long-term effects of both treatments on physiological and behavioral outcomes. Grafted GRPs reversed anxiety-like deficits and demonstrated an antidepressant-like effect, while the secretome promoted recovery of only anxiety-like behavior. Furthermore, GRPs elicited a recovery of neurogenic and gliogenic levels in the ventral DG, highlighting the unique involvement of these cells in the regulation of brain cytogenesis. Both GRPs and their secretome induced significant alterations in the DG proteome, directly influencing proteins and pathways related to cytogenesis, regulation of neural plasticity and neuronal development. With this work, we demonstrate a valuable and specific contribution of glial progenitors to normalizing gliogenic levels, rescuing neurogenesis and, importantly, promoting recovery of emotional deficits characteristic of disorders such as MDD.

3.
Acta Med Port ; 37(1): 10-19, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37489611

RESUMO

INTRODUCTION: Liquid biopsies based on plasma circulating tumour deoxyribonucleic acid (ctDNA) have shown promise in monitoring lung cancer evolution. The expression of ctDNA across time, its relationship with clinicopathological parameters and its association with lung cancer progression through imaging allow us to weigh how useful ctDNA could be in monitoring surgically resectable lung cancer. The aim of this study was to assess the impact of ctDNA analysis implementation in early-stage lung cancer. METHODS: A cohort of 47 patients was sequentially recruited. Only 34 patients with early-stage lung cancer were included. All patients had a tissue specimen and five blood samples drawn: at the preoperative stage, from the pulmonary vein, at surgical discharge, at the first follow-up and at the last follow-up. All blood samples were evaluated for ctDNA expression. RESULTS: On average, the maximum yield of ctDNA was obtained in liquid biopsies at the surgical discharge of patients when compared with PO, PV, and F1 (p < 0.0001, p < 0.0001, p < 0.0001 respectively). No statistically significant differences were found when comparing the last follow-up to surgical discharge ctDNA expression (p = 0.851). The correlation between ctDNA concentration according to five-time points and the four clinicopathological characteristics showed that patients younger than 70 years had a statistically significant reduction of the concentration of ctDNA at the preoperative and surgical discharge time point [ß = -16 734 (-27 707; - 5760); p = 0.003; ß = -21 785 (-38 447; -5123); p = 0.010], as opposed to an increase of the concentration of ctDNA at the pulmonary vein and last follow-up time points [ß = 8369 (0.359; 16 378); p = 0.041; ß = 34 402 (12 549; 56 254); p = 0.002] all with a confidence level of 95%. In the cases where actionable mutations were identified in tissue biopsies, the expected mutation was found in five out of six patients plasma samples at the pre-operatory time point and in two out of six patients plasma samples at the pulmonary vein time point. Two out of six patients with actionable mutations had disease progression. CONCLUSION: The results of this pilot study suggest that the maximum yield of ctDNA is obtained at the surgical discharge of the patients and that the pre-operatory timepoint is the one offering the highest sensitivity for the detection of actionable mutations in ctDNA in early-stage lung cancer.


Assuntos
DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Projetos Piloto
4.
Antioxidants (Basel) ; 12(6)2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37371987

RESUMO

Preventing degeneration and the loss of dopaminergic neurons (DAn) in the brain while mitigating motor symptoms remains a challenge in Parkinson's Disease (PD) treatment development. In light of this, developing or repositioning potential disease-modifying approaches is imperative to achieve meaningful translational gains in PD research. Under this concept, N-acetylcysteine (NAC) has revealed promising perspectives in preserving the dopaminergic system capability and modulating PD mechanisms. Although NAC has been shown to act as an antioxidant and (neuro)protector of the brain, it has yet to be acknowledged how this repurposed drug can improve motor symptomatology and provide disease-modifying properties in PD. Therefore, in the present work, we assessed the impact of NAC on motor and histological deficits in a striatal 6-hydroxydopamine (6-OHDA) rat model of PD. The results revealed that NAC enhanced DAn viability, as we found that it could restore dopamine transporter (DAT) levels compared to the untreated 6-OHDA group. Such findings were positively correlated with a significant amelioration in the motor outcomes of the 6-OHDA-treated animals, demonstrating that NAC may, somehow, be a modulator of PD degenerative mechanisms. Overall, we postulated a proof-of-concept milestone concerning the therapeutic application of NAC. Nevertheless, it is extremely important to understand the complexity of this drug and how its therapeutical properties interact with the cellular and molecular PD mechanisms.

5.
Proc Natl Acad Sci U S A ; 120(20): e2214853120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155874

RESUMO

Gastric cancer is a dominating cause of cancer-associated mortality with limited therapeutic options. Here, we show that syndecan-4 (SDC4), a transmembrane proteoglycan, is highly expressed in intestinal subtype gastric tumors and that this signature associates with patient poor survival. Further, we mechanistically demonstrate that SDC4 is a master regulator of gastric cancer cell motility and invasion. We also find that SDC4 decorated with heparan sulfate is efficiently sorted in extracellular vesicles (EVs). Interestingly, SDC4 in EVs regulates gastric cancer cell-derived EV organ distribution, uptake, and functional effects in recipient cells. Specifically, we show that SDC4 knockout disrupts the tropism of EVs for the common gastric cancer metastatic sites. Our findings set the basis for the molecular implications of SDC4 expression in gastric cancer cells and provide broader perspectives on the development of therapeutic strategies targeting the glycan-EV axis to limit tumor progression.


Assuntos
Neoplasias Gástricas , Sindecana-4 , Humanos , Heparitina Sulfato/metabolismo , Invasividade Neoplásica , Neoplasias Gástricas/genética , Sindecana-4/genética , Sindecana-4/metabolismo
6.
Res Sq ; 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37034743

RESUMO

Adult cytogenesis, the continuous generation of newly-born neurons (neurogenesis) and glial cells (gliogenesis) throughout life, is highly impaired in several neuropsychiatric disorders, such as Major Depressive Disorder (MDD), impacting negatively on cognitive and emotional domains. Despite playing a critical role in brain homeostasis, the importance of gliogenesis has been overlooked, both in healthy and diseased states. To examine the role of newly formed glia, we transplanted Glial Restricted Precursors (GRPs) into the adult hippocampal dentate gyrus (DG), or injected their secreted factors (secretome), into a previously validated transgenic GFAP-tk rat line, in which cytogenesis is transiently compromised. We explored the long-term effects of both treatments on physiological and behavioral outcomes. Grafted GRPs reversed anxiety-like and depressive-like deficits, while the secretome promoted recovery of only anxiety-like behavior. Furthermore, GRPs elicited a recovery of neurogenic and gliogenic levels in the ventral DG, highlighting the unique involvement of these cells in the regulation of brain cytogenesis. Both GRPs and their secretome induced significant alterations in the DG proteome, directly influencing proteins and pathways related to cytogenesis, regulation of neural plasticity and neuronal development. With this work, we demonstrate a valuable and specific contribution of glial progenitors to normalizing gliogenic levels, rescueing neurogenesis and, importantly, promoting recovery of emotional deficits characteristic of disorders such as MDD.

7.
Int J Pharm ; 637: 122854, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36948473

RESUMO

The present work studied the influence of different formulation variables (defined also as factors), namely, different polymers (HPC EF, PVA and HPMC-AS LG), drugs with different water solubilities (paracetamol, hydrochlorothiazide and celecoxib) and drug loads (10 or 30 %) on their processability by HME and FDM. Both filaments and tablets were characterized for physic and chemical properties (DSC, XRPD, FTIR) and performance properties (drug content, in vitro drug release). Experiments were designed to highlight relationships between the 3 factors selected and the mechanical properties of filaments, tablet mass and dissolution profiles of the model drugs from printed tablets. While the combination of hydrochlorothiazide and HPMC-AS LG could not be extruded, the combination of paracetamol with HPC EF turned the filaments too ductile and not stiff enough hampering the process of printing. All other polymer and drug combinations could be successfully extruded and printed. Models reflected the influence of the solubility of the drug considered but not the drug load in formulations. The ranking of the drug release rates was in good agreement with their solubilities. Furthermore, PVA presenting the fastest swelling rate, promoted the fastest drugs' releases in comparison with the other polymers studied. Overall, the study enabled the identification of the key factors affecting the properties of printed tablets, with the proposal of a model that has valued the relative contribution of each factor to the overall performance of tablets.


Assuntos
Composição de Medicamentos , Comprimidos , Comprimidos/química , Comprimidos/farmacologia , Composição de Medicamentos/métodos , Polímeros/química , Polímeros/farmacologia , Acetaminofen/administração & dosagem , Acetaminofen/farmacologia , Hidroclorotiazida/administração & dosagem , Hidroclorotiazida/farmacologia , Solubilidade , Tecnologia Farmacêutica , Celecoxib/administração & dosagem , Celecoxib/farmacologia , Impressão Tridimensional
8.
Pharmaceutics ; 15(2)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36839860

RESUMO

Diazepam (DZP) is a long-acting benzodiazepine to treat anxiety or acute alcohol withdrawal. Although this class of drugs should be taken for a short period of time, many patients take them for longer than recommended, which has been linked to an increased risk of dementia and dependence. The present work aimed at using the dual-nozzle system of fused deposition modeling (FDM) 3D printers to prepare tablets with gradual doses of DZP with constant mass and size. Placebo and DZP-loaded filaments were prepared by hot-melt extrusion and used to print the bi-compartmental tablets. Thermal processing allowed the conversion of crystalline DZP to its amorphous counterpart. Tablets with different DZP contents were effectively printed with a mass, thickness and diameter average of 111.6 mg, 3.1 mm, and 6.4 mm, respectively. Microscopic data showed good adhesion between the different layers in the printed tablets. The desired drug contents were successfully achieved and were within the acceptance criteria (European Pharmacopeia). The combination of a placebo and drug-loaded extrudates proved to be beneficial in the production of tablets by FDM for patients in need of drug withdrawal.

9.
Cells ; 12(3)2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36766724

RESUMO

Major depressive disorder (MDD) is a multidimensional psychiatric disorder that is estimated to affect around 350 million people worldwide. Generating valid and effective animal models of depression is critical and has been challenging for neuroscience researchers. For preclinical studies, models based on stress exposure, such as unpredictable chronic mild stress (uCMS), are amongst the most reliable and used, despite presenting concerns related to the standardization of protocols and time consumption for operators. To overcome these issues, we developed an automated system to expose rodents to a standard uCMS protocol. Here, we compared manual (uCMS) and automated (auCMS) stress-exposure protocols. The data shows that the impact of the uCMS exposure by both methods was similar in terms of behavioral (cognition, mood, and anxiety) and physiological (cell proliferation and endocrine variations) measurements. Given the advantages of time and standardization, this automated method represents a step forward in this field of preclinical research.


Assuntos
Transtorno Depressivo Maior , Ratos , Animais , Ansiedade , Cognição
10.
Cells ; 11(18)2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-36139483

RESUMO

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder worldwide. Clinically, it is characterized by a progressive degeneration of dopaminergic neurons (DAn), resulting in severe motor complications. Preclinical and clinical studies have indicated that neuroinflammation can play a role in PD pathophysiology, being associated with its onset and progression. Nevertheless, several key points concerning the neuroinflammatory process in PD remain to be answered. Bearing this in mind, in the present review, we cover the impact of neuroinflammation on PD by exploring the role of inflammatory cells (i.e., microglia and astrocytes) and the interconnections between the brain and the peripheral system. Furthermore, we discuss both the innate and adaptive immune responses regarding PD pathology and explore the gut-brain axis communication and its influence on the progression of the disease.


Assuntos
Doenças Neurodegenerativas , Doença de Parkinson , Neurônios Dopaminérgicos/patologia , Humanos , Microglia/patologia , Doenças Neurodegenerativas/patologia , Doenças Neuroinflamatórias , Doença de Parkinson/etiologia
11.
J Pharm Sci ; 111(10): 2814-2826, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35577114

RESUMO

Tablet manufacture by fused deposition modelling (FDM) can be carried out individually (one tablet printed per run) or as a group (i.e., 'multiple printing' in one run) depending on patient's needs. The assessment of the process of printing must take into consideration the precision and the accuracy of the mass and dose of tablets, together with their solid-state properties and drug dissolution behaviour. Different mixtures made of either poly(vinyl alcohol) and paracetamol or hydroxypropylcellulose EF and hydrochlorothiazide were used to evaluate multiple printing of tablets by manufacturing batches of 30 tablets with nozzles of 0.4 and 0.7 mm, in two different printers. Besides testing for mass, drug content, density and dissolution performance, tablets were analysed for their thermal (DSC) and spectroscopic (NIR and FTIR) properties. Low standard deviations around mean values for the different properties measured suggested low intra-batch variability. Statistical analysis of data revealed no significant differences between the batches for most of the properties considered in the study. Inter-batch differences (p<0.05) were observed only for mass of tablets, possibly due to deviation on filament's diameter. The use of a smaller nozzle or a different printer enabled the manufacture of more reproducible tablets within a batch. Multiple printing revealed a significant saving on manufacturing time (>35%) in comparison to individual printing.


Assuntos
Álcool de Polivinil , Tecnologia Farmacêutica , Acetaminofen , Liberação Controlada de Fármacos , Humanos , Hidroclorotiazida , Álcool de Polivinil/química , Impressão Tridimensional , Comprimidos/química , Tecnologia Farmacêutica/métodos
12.
Cell Prolif ; 55(2): e13165, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34970787

RESUMO

OBJECTIVES: The action of stress hormones, mainly glucocorticoids, starts and coordinates the systemic response to stressful events. The HPA axis activity is predicated on information processing and modulation by upstream centres, such as the hippocampus where adult-born neurons (hABN) have been reported to be an important component in the processing and integration of new information. Still, it remains unclear whether and how hABN regulates HPA axis activity and CORT production, particularly when considering sex differences. MATERIALS AND METHODS: Using both sexes of a transgenic rat model of cytogenesis ablation (GFAP-Tk rat model), we examined the endocrinological and behavioural effects of disrupting the generation of new astrocytes and neurons within the hippocampal dentate gyrus (DG). RESULTS: Our results show that GFAP-Tk male rats present a heightened acute stress response. In contrast, GFAP-Tk female rats have increased corticosterone secretion at nadir, a heightened, yet delayed, response to an acute stress stimulus, accompanied by neuronal hypertrophy in the basal lateral amygdala and increased expression of the glucocorticoid receptors in the ventral DG. CONCLUSIONS: Our results reveal that hABN regulation of the HPA axis response is sex-differentiated.


Assuntos
Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/diagnóstico por imagem , Sistema Hipófise-Suprarrenal/metabolismo , Diferenciação Sexual/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Corticosterona/metabolismo , Corticosterona/farmacologia , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Masculino , Neurônios/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Ratos Transgênicos , Receptores de Glucocorticoides/metabolismo , Diferenciação Sexual/fisiologia
13.
Nat Aging ; 2(5): 397-411, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-37118067

RESUMO

The FOXM1 transcription factor exhibits pleiotropic C-terminal transcriptional and N-terminal non-transcriptional functions in various biological processes critical for cellular homeostasis. We previously found that FOXM1 repression during cellular aging underlies the senescence phenotypes, which were vastly restored by overexpressing transcriptionally active FOXM1. Yet, it remains unknown whether increased expression of FOXM1 can delay organismal aging. Here, we show that in vivo cyclic induction of an N-terminal truncated FOXM1 transgene on progeroid and naturally aged mice offsets aging-associated repression of full-length endogenous Foxm1, reinstating both transcriptional and non-transcriptional functions. This translated into mitigation of several cellular aging hallmarks, as well as molecular and histopathological progeroid features of the short-lived Hutchison-Gilford progeria mouse model, significantly extending its lifespan. FOXM1 transgene induction also reinstated endogenous Foxm1 levels in naturally aged mice, delaying aging phenotypes while extending their lifespan. Thus, we disclose that FOXM1 genetic rewiring can delay senescence-associated progeroid and natural aging pathologies.


Assuntos
Envelhecimento , Fatores de Transcrição , Animais , Camundongos , Envelhecimento/genética , Senescência Celular/genética , Regulação da Expressão Gênica , Fenótipo , Fatores de Transcrição/genética
14.
Neurosci Biobehav Rev ; 131: 411-428, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555383

RESUMO

Psychiatric disorders severely impact patients' lives. Motivational, cognitive and emotional deficits are the most common symptoms observed in these patients and no effective treatment is still available, either due to the adverse side effects or the low rate of efficacy of currently available drugs. Neurogenesis recovery has been one important focus in the treatment of psychiatric disorders, which undeniably contributes to the therapeutic action of antidepressants. However, glial plasticity is emerging as a new strategy to explore the deficits observed in mood disorders and the efficacy of therapeutic interventions. Thus, it is crucial to understand the mechanisms behind glio- and neurogenesis to better define treatments and preventive therapies, once adult cytogenesis is of pivotal importance to cognitive and emotional components of behavior, both in healthy and pathological contexts, including in psychiatric disorders. Here, we review the concepts and history of neuro- and gliogenesis, providing as well a reflection on the functional importance of cytogenesis in the context of disease.


Assuntos
Transtornos do Humor , Neurogênese , Adulto , Encéfalo , Emoções , Humanos , Neuroglia
15.
Mol Psychiatry ; 26(12): 7154-7166, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34521994

RESUMO

Impaired ability to generate new cells in the adult brain has been linked to deficits in multiple emotional and cognitive behavioral domains. However, the mechanisms by which abrogation of adult neural stem cells (NSCs) impacts on brain function remains controversial. We used a transgenic rat line, the GFAP-Tk, to selectively eliminate NSCs and assess repercussions on different behavioral domains. To assess the functional importance of newborn cells in specific developmental stages, two parallel experimental timeframes were adopted: a short- and a long-term timeline, 1 and 4 weeks after the abrogation protocol, respectively. We conducted in vivo electrophysiology to assess the effects of cytogenesis abrogation on the functional properties of the hippocampus and prefrontal cortex, and on their intercommunication. Adult brain cytogenesis abrogation promoted a time-specific installation of behavioral deficits. While the lack of newborn immature hippocampal neuronal and glial cells elicited a behavioral phenotype restricted to hyperanxiety and cognitive rigidity, specific abrogation of mature new neuronal and glial cells promoted the long-term manifestation of a more complex behavioral profile encompassing alterations in anxiety and hedonic behaviors, along with deficits in multiple cognitive modalities. More so, abrogation of 4 to 7-week-old cells resulted in impaired electrophysiological synchrony of neural theta oscillations between the dorsal hippocampus and the medial prefrontal cortex, which are likely to contribute to the described long-term cognitive alterations. Hence, this work provides insight on how newborn neurons and astrocytes display different functional roles throughout different maturation stages, and establishes common ground to reconcile contrasting results that have marked this field.


Assuntos
Disfunção Cognitiva , Hipocampo , Células-Tronco Neurais , Córtex Pré-Frontal , Animais , Cognição/fisiologia , Disfunção Cognitiva/patologia , Emoções , Hipocampo/patologia , Células-Tronco Neurais/patologia , Neurônios/patologia , Córtex Pré-Frontal/patologia , Ratos , Ratos Transgênicos
16.
Cell Death Dis ; 12(6): 542, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34035233

RESUMO

Inhibition of spindle microtubule (MT) dynamics has been effectively used in cancer treatment. Although the mechanisms by which MT poisons elicit mitotic arrest are fairly understood, efforts are still needed towards elucidating how cancer cells respond to antimitotic drugs owing to cytotoxicity and resistance side effects. Here, we identified the critical G2/M transcription factor Forkhead box M1 (FOXM1) as a molecular determinant of cell response to antimitotics. We found FOXM1 repression to increase death in mitosis (DiM) due to upregulation of the BCL-2 modifying factor (BMF) gene involved in anoikis, an apoptotic process induced upon cell detachment from the extracellular matrix. FOXM1 binds to a BMF intronic cis-regulatory element that interacts with both the BMF and the neighbor gene BUB1B promoter regions, to oppositely regulate their expression. This mechanism ensures that cells treated with antimitotics repress BMF and avoid DiM when FOXM1 levels are high. In addition, we show that this mechanism is partly disrupted in anoikis/antimitotics-resistant tumor cells, with resistance correlating with lower BMF expression but in a FOXM1-independent manner. These findings provide a stratification biomarker for antimitotic chemotherapy response.


Assuntos
Antimitóticos/farmacologia , Morte Celular , Proteína Forkhead Box M1/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Células Cultivadas , Criança , Regulação para Baixo/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Masculino , Mitose/efeitos dos fármacos , Mitose/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
17.
Chromosome Res ; 29(2): 159-173, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33587225

RESUMO

CLASPs are key modulators of microtubule dynamics throughout the cell cycle. During mitosis, CLASPs independently associate with growing microtubule plus-ends and kinetochores and play essential roles in chromosome segregation. In a proteomic survey for human CLASP1-interacting proteins during mitosis, we have previously identified SOGA1 and SOGA2/MTCL1, whose mitotic roles remained uncharacterized. Here we performed an initial functional characterization of human SOGA1 and SOGA2/MTCL1 during mitosis. Using specific polyclonal antibodies raised against SOGA proteins, we confirmed their expression and reciprocal interaction with CLASP1 and CLASP2 during mitosis. In addition, we found that both SOGA1 and SOGA2/MTCL1 are phospho-regulated during mitosis by CDK1. Immunofluorescence analysis revealed that SOGA2/MTCL1 co-localizes with mitotic spindle microtubules and spindle poles throughout mitosis and both SOGA proteins are enriched at the midbody during mitotic exit/cytokinesis. GFP-tagging of SOGA2/MTCL1 further revealed a microtubule-independent localization at kinetochores. Live-cell imaging after siRNA-mediated knockdown of SOGA1 and SOGA2/MTCL1 showed that they are independently required for distinct aspects of chromosome segregation. Thus, SOGA1 and SOGA2/MTCL1 are bona fide CLASP-interacting proteins during mitosis required for faithful chromosome segregation in human cells.


Assuntos
Segregação de Cromossomos , Proteômica , Humanos , Cinetocoros , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos , Fuso Acromático
18.
Glia ; 69(3): 513-531, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33052610

RESUMO

The crosstalk between glial cells and neurons represents an exceptional feature for maintaining the normal function of the central nervous system (CNS). Increasing evidence has revealed the importance of glial progenitor cells in adult neurogenesis, reestablishment of cellular pools, neuroregeneration, and axonal (re)myelination. Several types of glial progenitors have been described, as well as their potentialities for recovering the CNS from certain traumas or pathologies. Among these precursors, glial-restricted precursor cells (GRPs) are considered the earliest glial progenitors and exhibit tripotency for both Type I/II astrocytes and oligodendrocytes. GRPs have been derived from embryos and embryonic stem cells in animal models and have maintained their capacity for self-renewal. Despite the relatively limited knowledge regarding the isolation, characterization, and function of these progenitors, GRPs are promising candidates for transplantation therapy and reestablishment/repair of CNS functions in neurodegenerative and neuropsychiatric disorders, as well as in traumatic injuries. Herein, we review the definition, isolation, characterization and potentialities of GRPs as cell-based therapies in different neurological conditions. We briefly discuss the implications of using GRPs in CNS regenerative medicine and their possible application in a clinical setting. MAIN POINTS: GRPs are progenitors present in the CNS with differentiation potential restricted to the glial lineage. These cells have been employed in the treatment of a myriad of neurodegenerative and traumatic pathologies, accompanied by promising results, herein reviewed.


Assuntos
Doenças do Sistema Nervoso Central , Neuroglia , Animais , Diferenciação Celular , Doenças do Sistema Nervoso Central/terapia , Neurônios , Células-Tronco
19.
Artigo em Inglês | MEDLINE | ID: mdl-32984278

RESUMO

Cervical spinal cord trauma represents more than half of the spinal cord injury (SCI) cases worldwide. Respiratory compromise, as well as severe limb motor deficits, are among the main consequences of cervical lesions. In the present work, a Gellan Gum (GG)-based hydrogel modified with GRGDS peptide, together with adipose tissue-derived stem/stromal cells (ASCs) and olfactory ensheathing cells (OECs), was used as a therapeutic strategy after a C2 hemisection SCI in rats. Hydrogel or cells alone, and a group without treatment, were also tested. Four weeks after injury, compound muscle action potentials (CMAPs) were performed to assess functional phrenic motor neuron (PhMN) innervation of the diaphragm; no differences were observed amongst groups, confirming that the PhMN pool located between C3 and C5 was not affected by the C2 injury or by the treatments. In the same line, the vast majority of diaphragmatic neuromuscular junctions remained intact. Five weeks post-injury, inspiratory bursting of the affected ipsilateral hemidiaphragm was evaluated through EMG recordings of dorsal, medial and ventral subregions of the muscle. All treatments significantly increased EMG amplitude at the ventral portion in comparison to untreated animals, but only the combinatorial group presented increased EMG amplitude at the medial portion of the hemidiaphragm. No differences were observed in forelimb motor function, neither in markers for axonal regrowth (neuronal tracers), astrogliosis (GFAP) and inflammatory cells (CD68). Moreover, using Von Frey testing of mechanical allodynia, it was possible to find a significant effect of the group combining hydrogel and cells on hypersensitivity; rats with a SCI displayed an increased response of the contralateral forelimb to a normally innocuous mechanical stimulus, but after treatment with the combinatorial therapy this behavior was reverted almost to the levels of uninjured controls. These results suggest that our therapeutic approach may have beneficial effects on both diaphragmatic recovery and sensory function.

20.
J Pharm Sci ; 109(12): 3636-3644, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32949563

RESUMO

The aim of this study was to evaluate the processability of poly(vinyl alcohol) (PVA)-based filaments containing paracetamol (PAR) prepared by hot-melt extrusion for fused deposition modelling (FDM) 3D printing, as function of drug content (0-50%w/w) and storage conditions (temperature: 20-40 °C and humidity: 11-75%). Thermal (DSC), crystallographic (XRPD), spectroscopic (FTIR), moisture content and mechanical tests were used to characterize the filaments, whereas their ability to produce tablets was confirmed by printing. XRPD revealed the absence of crystalline PAR in the extruded filaments with <30% PAR and FTIR confirmed interactions between PAR and PVA. Mechanical tests have shown a higher brittleness of the filaments with increasing PAR, making them non-printable. Throughout storage, temperature and moisture increased the plasticity of the filaments, which was reflected by changes on their thermal and mechanical properties improving the feeding performance on the printer. Filaments stored at low moisture remained unsuitable for printing with amorphous PAR being preserved. Dissolution tests have shown that the release of PAR from printed tablets was independent of the storage time of the filaments. The study highlights the need for optimized storage conditions of filaments for FDM and the dependency on the drug's content in such filaments.


Assuntos
Acetaminofen , Liberação Controlada de Fármacos , Álcool de Polivinil , Tecnologia de Extrusão por Fusão a Quente , Impressão Tridimensional , Comprimidos
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