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1.
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
2.
Mol Psychiatry ; 29(7): 2185-2198, 2024 Jul.
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.


Assuntos
Modelos Animais de Doenças , Neurogênese , Neuroglia , Neurônios , Animais , Neurogênese/fisiologia , Neuroglia/metabolismo , Ratos , Masculino , Neurônios/metabolismo , Ansiedade/metabolismo , Transtorno Depressivo Maior/metabolismo , Ratos Transgênicos , Giro Denteado/metabolismo , Hipocampo/metabolismo , Emoções/fisiologia , Plasticidade Neuronal/fisiologia , Diferenciação Celular/fisiologia
3.
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
4.
EMBO Rep ; 21(5): e49248, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32134180

RESUMO

Chromosomal instability (CIN) refers to the rate at which cells are unable to properly segregate whole chromosomes, leading to aneuploidy. Besides its prevalence in cancer cells and postulated implications in promoting tumorigenesis, studies in aneuploidy-prone mouse models uncovered an unanticipated link between CIN and aging. Using young to old-aged human dermal fibroblasts, we observed a dysfunction of the mitotic machinery arising with age that mildly perturbs chromosome segregation fidelity and contributes to the generation of fully senescent cells. Here, we investigated mitotic mechanisms that contribute to age-associated CIN. We found that elderly cells have an increased number of stable kinetochore-microtubule (k-MT) attachments and decreased efficiency in the correction of improper k-MT interactions. Chromosome mis-segregation rates in old-aged cells decreased upon both genetic and small-molecule enhancement of MT-depolymerizing kinesin-13 activity. Notably, restored chromosome segregation accuracy inhibited the phenotypes of cellular senescence. Therefore, we provide mechanistic insight into age-associated CIN and disclose a strategy for the use of a small-molecule to inhibit age-associated CIN and to delay the cellular hallmarks of aging.


Assuntos
Instabilidade Cromossômica , Segregação de Cromossomos , Envelhecimento/genética , Senescência Celular/genética , Humanos , Microtúbulos
5.
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
6.
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
7.
Invest New Drugs ; 37(5): 1044-1051, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30680583

RESUMO

Obtustatin, isolated from the Levantine Viper snake venom (Macrovipera lebetina obtusa -MLO), is the shortest known monomeric disintegrin shown to specifically inhibit the binding of the α1ß1 integrin to collagen IV. Its oncostatic effect is due to the inhibition of angiogenesis, likely through α1ß1 integrin inhibition in endothelial cells. To explore the therapeutic potential of obtustatin, we studied its effect in S-180 sarcoma-bearing mice model in vivo as well as in human dermal microvascular endothelial cells (HMVEC-D) in vitro, and tested anti-angiogenic activity in vivo using the chick embryo chorioallantoic membrane assay (CAM assay). Our in vivo results show that obtustatin inhibits tumour growth by 33%. The expression of vascular endothelial growth factor (VEGF) increased after treatment with obtustatin, but the level of expression of caspase 8 did not change. In addition, our results demonstrate that obtustatin inhibits FGF2-induced angiogenesis in the CAM assay. Our in vitro results show that obtustatin does not exhibit cytotoxic activity in HMVEC-D cells in comparison to in vivo results. Thus, our findings disclose that obtustatin might be a potential candidate for the treatment of sarcoma in vivo with low toxicity.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Neovascularização Patológica/tratamento farmacológico , Sarcoma Experimental/tratamento farmacológico , Venenos de Víboras/farmacologia , Animais , Apoptose , Proliferação de Células , Embrião de Galinha , Membrana Corioalantoide , Integrina alfa1beta1/antagonistas & inibidores , Camundongos , Neovascularização Patológica/patologia , Sarcoma Experimental/irrigação sanguínea , Sarcoma Experimental/patologia , Células Tumorais Cultivadas
8.
Cell Immunol ; 333: 46-57, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29576316

RESUMO

Tumour metastasis is the main cause of cancer related deaths. Metastasis is an intricate multi-step process that requires the acquisition of several cancer cell features, including the modulation of tumour cell migration, adhesion, invasion, and immune evasion. Changes in the cellular glycosylation are associated with malignant transformation of cancer cells, tumour progression and ultimately, metastasis formation. Glycans have major impact on cellular signalling and on the regulation of tumour cell-cell adhesion and cell-matrix interaction. Glycans drive the interplay between the cancer cells and the tumour microenvironment. In this review, we summarize the roles of glycan alterations in tumour progression, such as acquisition of oncogenic features due to modulation of receptor tyrosine kinases, proteoglycans, cadherins and integrins. We also highlight the importance of key glycan binding proteins such as selectins, siglecs and galectins, which are pivotal in the modulation of immune response. An overview on glycans as cancer biomarkers is also presented.


Assuntos
Metástase Neoplásica/imunologia , Metástase Neoplásica/patologia , Neoplasias/imunologia , Neoplasias/patologia , Polissacarídeos/imunologia , Animais , Biomarcadores Tumorais/imunologia , Adesão Celular/imunologia , Adesão Celular/fisiologia , Progressão da Doença , Glicosilação , Humanos
9.
Adv Exp Med Biol ; 1002: 153-188, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28600786

RESUMO

Aging is a biological process characterized by the progressive deterioration of physiological functions known to be the main risk factor for chronic diseases and declining health. There has been an emerging connection between aging and aneuploidy, an aberrant number of chromosomes, even though the molecular mechanisms behind age-associated aneuploidy remain largely unknown. In recent years, several genetic pathways and biochemical processes controlling the rate of aging have been identified and proposed as aging hallmarks. Primary hallmarks that cause the accumulation of cellular damage include genomic instability, telomere attrition, epigenetic alterations and loss of proteostasis (López-Otín et al., Cell 153:1194-1217, 2013). Here we review the provocative link between these aging hallmarks and the loss of chromosome segregation fidelity during cell division, which could support the correlation between aging and aneuploidy seen over the past decades. Secondly, we review the systemic impacts of aneuploidy in cell physiology and emphasize how these include some of the primary hallmarks of aging. Based on the evidence, we propose a mutual causality between aging and aneuploidy, and suggest modulation of mitotic fidelity as a potential means to ameliorate healthy lifespan.


Assuntos
Envelhecimento/patologia , Senescência Celular , Mitose , Fatores Etários , Envelhecimento/genética , Envelhecimento/metabolismo , Aneuploidia , Animais , Segregação de Cromossomos , Epigênese Genética , Instabilidade Genômica , Genótipo , Humanos , Fenótipo , Encurtamento do Telômero
10.
Biochim Biophys Acta ; 1842(7): 981-91, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24530636

RESUMO

Prion diseases are associated to the conversion of the prion protein into a misfolded pathological isoform. The mechanism of propagation of protein misfolding by protein templating remains largely unknown. Neuroblastoma cells were transfected with constructs of the prion protein fused to both CFP-GPI-anchored and to YFP-GPI-anchored and directed to its cell membrane location. Live-cell FRET imaging between the prion protein fused to CFP or YFP was measured giving consistent values of 10±2%. This result was confirmed by fluorescence lifetime imaging microscopy and indicates intermolecular interactions between neighbor prion proteins. In particular, considering that a maximum FRET efficiency of 17±2% was determined from a positive control consisting of a fusion CFP-YFP-GPI-anchored. A stable cell clone expressing the two fusions containing the prion protein was also selected to minimize cell-to-cell variability. In both, stable and transiently transfected cells, the FRET efficiency consistently increased in the presence of infectious prions - from 4±1% to 7±1% in the stable clone and from 10±2% to 16±1% in transiently transfected cells. These results clearly reflect an increased clustering of the prion protein on the membrane in the presence of infectious prions, which was not observed in negative control using constructs without the prion protein and upon addition of non-infected brain. Our data corroborates the recent view that the primary site for prion conversion is the cell membrane. Since our fluorescent cell clone is not susceptible to propagate infectivity, we hypothesize that the initial event of prion infectivity might be the clustering of the GPI-anchored prion protein.


Assuntos
Príons/metabolismo , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Membrana Celular/química , Membrana Celular/metabolismo , Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Microscopia de Fluorescência/métodos , Príons/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo
11.
Proteins ; 83(11): 2039-51, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26344410

RESUMO

Amyloid fibers, implicated in a wide range of diseases, are formed when proteins misfold and stick together in long rope-like structures. As a natural mechanism, osmolytes can be used to modulate protein aggregation pathways with no interference with other cellular functions. The osmolyte sucrose delays fibrillation of the ribosomal protein S6 leading to softer and less shaped-defined fibrils. The molecular mechanism used by sucrose to delay S6 fibrillation was studied based on the two-state unfolding kinetics of the secondary and tertiary structures. It was concluded that the delay in S6 fibrillation results from stabilization and compaction of the slightly expanded tertiary native structure formed under fibrillation conditions. Interestingly, this compaction extends to almost all S6 tertiary structure but hardly affects its secondary structure. The part of the S6 tertiary structure that suffered more compaction by sucrose is known to be the first part to unfold, indicating that the native S6 has entered the unfolding pathway under fibrillation conditions.


Assuntos
Amiloide/química , Sacarose/química , Amiloide/metabolismo , Agregados Proteicos/efeitos dos fármacos , Conformação Proteica , Engenharia de Proteínas , Sacarose/farmacologia
12.
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
13.
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
14.
BMC Cancer ; 13: 169, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23548132

RESUMO

BACKGROUND: KRAS is an EGFR effector in the RAS/RAF/ERK cascade that is mutated in about 40% of metastatic colorectal cancer (mCRC). Activating mutations in codons 12 and 13 of the KRAS gene are the only established negative predictors of response to anti-EGFR therapy and patients whose tumors harbor such mutations are not candidates for therapy. However, 40 to 60% of wild-type cases do not respond to anti-EGFR therapy, suggesting the involvement of other genes that act downstream of EGFR in the RAS-RAF-MAPK and PI3K-AKT pathways or activating KRAS mutations at other locations of the gene. METHODS: DNA was obtained from a consecutive series of 201 mCRC cases (FFPE tissue), wild-type for KRAS exon 2 (codons 12 and 13). Mutational analysis of KRAS (exons 3 and 4), BRAF (exons 11 and 15), and PIK3CA (exons 9 and 20) was performed by high resolution melting (HRM) and positive cases were then sequenced. RESULTS: One mutation was present in 23.4% (47/201) of the cases and 3.0% additional cases (6/201) had two concomitant mutations. A total of 53 cases showed 59 mutations, with the following distribution: 44.1% (26/59) in KRAS (13 in exon 3 and 13 in exon 4), 18.6% (11/59) in BRAF (two in exon 11 and nine in exon 15) and 37.3% (22/59) in PIK3CA (16 in exon 9 and six in exon 20). In total, 26.4% (53/201) of the cases had at least one mutation and the remaining 73.6% (148/201) were wild-type for all regions studied. Five of the mutations we report, four in KRAS and one in BRAF, have not previously been described in CRC. BRAF and PIK3CA mutations were more frequent in the colon than in the sigmoid or rectum: 20.8% vs. 1.6% vs. 0.0% (P=0.000) for BRAF and 23.4% vs. 12.1% vs. 5.4% (P=0.011) for PIK3CA mutations. CONCLUSIONS: About one fourth of mCRC cases wild-type for KRAS codons 12 and 13 present other mutations either in KRAS, BRAF, or PIK3CA, many of which may explain the lack of response to anti-EGFR therapy observed in a significant proportion of these patients.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Éxons , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Sequência de Bases , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Metástase Neoplásica , Técnicas de Amplificação de Ácido Nucleico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras) , Temperatura de Transição , Resultado do Tratamento
15.
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.

16.
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
17.
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.

18.
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.

19.
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
20.
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
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