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1.
Biology (Basel) ; 12(9)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37759624

RESUMO

Increasing reports of neurological and psychiatric outcomes due to psychostimulant synthetic cathinones (SCs) have recently raised public concern. However, the understanding of neurotoxic mechanisms is still lacking, particularly for the under-investigated αPHP, one of the major MDPV derivatives. In particular, its effects on neural stem/progenitor cell cultures (NSPCs) are still unexplored. Therefore, in the current in vitro study, the effects of increasing αPHP concentrations (25-2000 µM), on cell viability/proliferation, morphology/ultrastructure, genotoxicity and cell death pathways, have been evaluated after exposure in murine NSPCs, using a battery of complementary techniques, i.e., MTT and clonogenic assay, flow cytometry, immunocytochemistry, TEM, and patch clamp. We revealed that αPHP was able to induce a dose-dependent significant decrease of the viability, proliferation and clonal capability of the NSPCs, paralleled by the resting membrane potential depolarization and apoptotic/autophagic/necroptotic pathway activation. Moreover, ultrastructural alterations were clearly observed. Overall, our current findings demonstrate that αPHP, damaging NSPCs and the morpho-functional fundamental units of adult neurogenic niches may affect neurogenesis, possibly triggering long-lasting, irreversible CNS damage. The present investigation could pave the way for a broadened understanding of SCs toxicology, needed to establish an appropriate treatment for NPS and the potential consequences for public health.

2.
Int. j. morphol ; 40(3): 697-705, jun. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1385688

RESUMO

SUMMARY: An association between certain food additives and chronic diseases is reported. Current study determined whether administering toxic doses of the food additive monosodium glutamate (MSG) into rats can induce aortopathy in association with the oxidative stress and inflammatory biomarkers upregulation and whether the effects of MSG overdose can be inhibited by vitamin E. MSG at a dose of (4 mg/kg; orally) that exceeds the average human daily consumption by 1000x was administered daily for 7 days to the rats in the model group. Whereas, rats treated with vitamin E were divided into two groups and given daily doses of MSG plus 100 mg/ kg vitamin E or MSG plus 300 mg/kg vitamin E. On the eighth day, all rats were culled. Using light and electron microscopy examinations, a profound aortic injury in the model group was observed demonstrated by damaged endothelial layer, degenerated smooth muscle cells (SMC) with vacuoles and condensed nuclei, vacuolated cytoplasm, disrupted plasma membrane, interrupted internal elastic lamina, clumped chromatin, and damaged actin and myosin filaments. Vitamin E significantly protected aorta tissue and cells as well as inhibited MSG-induced tissue malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). The highest used vitamin E dosage was more effective. Additionally, a significant correlation was observed between the aortic injury degree and tissue MDA, TNF-α, IL-6, and superoxide dismutase (SOD) levels (p=0.001). Vitamin E effectively protects against aortopathy induced by toxic doses of MSG in rats and inhibits oxidative stress and inflammation.


RESUMEN: Se reporta una asociación entre ciertos aditivos alimentarios y enfermedades crónicas. El objetivo de este estudio fue determinar si la administración de dosis tóxicas del aditivo alimentario glutamato monosódico (MSG) en ratas puede inducir aortopatía en asociación con el estrés oxidativo y la regulación positiva de los biomarcadores inflamatorios y si el efecto de una sobredosis de MSG se puede inhibir con vitamina E. Se administró MSG diariamente durante 7 días una dosis de (4 g/kg; por vía oral) que excede el consumo diario humano promedio, en 1000x a las ratas del grupo modelo. Mientras que las ratas tratadas con vitamina E se dividieron en dos grupos y se administraron dosis diarias de MSG más 100 mg/kg de vitamina E o MSG más 300 mg/kg de vitamina E. Todas las ratas fueron sacrificadas en el octavo día. Usando exámenes de microscopía óptica y electrónica, se observó una lesión aórtica profunda en el grupo modelo demostrada por una capa endotelial dañada, células musculares lisas degeneradas (SMC) con vacuolas y núcleos condensados, citoplasma vacuolado, membrana plasmática rota, lámina elástica interna interrumpida, cromatina agrupada y filamentos de actina y miosina dañados. La vitamina E protegió significativamente el tejido y las células de la aorta, además de inhibir el malondialdehído tisular (MDA) inducido por MSG, la interleucina-6 (IL-6) y el factor de necrosis tumoral alfa (TNF-α). La dosis más alta de vitamina E utilizada fue más efectiva. Además, se observó una correlación significativa entre el grado de lesión aórtica y los niveles tisulares de MDA, TNF-α, IL-6 y superóxido dismutasa (SOD) (p=0,001). La vitamina E efectivamente protege contra la aortopatía inducida por dosis tóxicas de MSG en ratas e inhibe el estrés oxidativo y la inflamación.


Assuntos
Animais , Ratos , Aorta/efeitos dos fármacos , Doenças da Aorta/induzido quimicamente , Glutamato de Sódio/toxicidade , Vitamina E/farmacologia , Aorta/patologia , Glutamato de Sódio/administração & dosagem , Vitamina E/administração & dosagem , Microscopia Eletrônica , Interleucina-6/antagonistas & inibidores , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Ratos Sprague-Dawley , Estresse Oxidativo/efeitos dos fármacos , Modelos Animais de Doenças , Malondialdeído/antagonistas & inibidores
3.
Cells ; 9(1)2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947766

RESUMO

It is believed that mitochondrial fragmentation cause mitochondrial dysfunction and neuronal deficits in Alzheimer's disease. We recently reported that constitutive knockout of the mitochondria fusion protein mitofusin2 (Mfn2) in the mouse brain causes mitochondrial fragmentation and neurodegeneration in the hippocampus and cortex. Here, we utilize an inducible mouse model to knock out Mfn2 (Mfn2 iKO) in adult mouse hippocampal and cortical neurons to avoid complications due to developmental changes. Electron microscopy shows the mitochondria become swollen with disorganized and degenerated cristae, accompanied by increased oxidative damage 8 weeks after induction, yet the neurons appear normal at the light level. At later timepoints, increased astrocyte and microglia activation appear and nuclei become shrunken and pyknotic. Apoptosis (Terminal deoxynucleotidyl transferase dUTP nick end labeling, TUNEL) begins to occur at 9 weeks, and by 12 weeks, most hippocampal neurons are degenerated, confirmed by loss of NeuN. Prior to the loss of NeuN, aberrant cell-cycle events as marked by proliferating cell nuclear antigen (PCNA) and pHistone3 were evident in some Mfn2 iKO neurons but do not colocalize with TUNEL signals. Thus, this study demonstrated that Mfn2 ablation and mitochondrial fragmentation in adult neurons cause neurodegeneration through oxidative stress and neuroinflammation in vivo via both apoptosis and aberrant cell-cycle-event-dependent cell death pathways.


Assuntos
Envelhecimento/patologia , Apoptose , GTP Fosfo-Hidrolases/deficiência , Hipocampo/patologia , Neurônios/metabolismo , Neurônios/patologia , Animais , Biomarcadores/metabolismo , Proteínas de Ciclo Celular/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Inflamação/patologia , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Degeneração Neural/patologia , Estresse Oxidativo , Recombinação Genética/genética
4.
Parasit Vectors ; 11(1): 58, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29368624

RESUMO

BACKGROUND: Cystic echinococcosis is a global public health problem; however, the drugs (albendazole and mebendazole) currently recommended by WHO for its treatment, have limited efficacy. Therefore, novel drugs are required to provide more choices for the treatment of this disease. METHODS: The anthelmintic effects of ursolic acid (UA) were tested on Echinococcus granulosus protoscoleces, germinal cells and metacestodes in vitro. The in vivo efficacy of UA was investigated in mice following secondary infection with E. granulosus. Furthermore, the corresponding ultrastructural damage induced by UA was evaluated by electron microscopy. RESULTS: In vitro, 45.95 ± 5.30% of protoscoleces were killed by UA at 40 µg/ml, while the growth of more than 90% of germinal cells was inhibited by UA at 10 to 40 µg/ml. The same effect was observed in metacestodes 7 days after treatment with UA at 10, 20 and 40 µg/ml, and more than 50% of metacestodes showed loss of integrity at the end of the experiment. In vivo, metacestode weight was significantly reduced following oral administration of UA at 200 and 100 mg/kg (39.5 and 38.3%, respectively). Additionally, ultrastructural damage, such as alternations in germinal cell morphology and formation of vacuoles and lipid granules were observed in parasites treated with UA in vitro, while detachment of the germinal layer from the laminated layer was also seen in metacestodes in vivo. CONCLUSIONS: UA was demonstrated to exert parasiticidal activity against E. granulosus in vitro and in vivo, thus implicating UA as a potential anti-echinococcosis agent.


Assuntos
Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Equinococose/tratamento farmacológico , Echinococcus granulosus/efeitos dos fármacos , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Animais , Modelos Animais de Doenças , Equinococose/parasitologia , Echinococcus granulosus/ultraestrutura , Técnicas In Vitro , Larva/efeitos dos fármacos , Camundongos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Triterpenos/administração & dosagem
5.
Environ Sci Pollut Res Int ; 24(6): 5781-5790, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28054265

RESUMO

The aim of this study was to assess the effects of arsenic trioxide (As2O3) in the chicken heart, and 72 1-day-old male Hy-line chickens were fed either a commercial diet (C group) or an arsenic supplement diet containing 7.5 mg/kg (L group), 15 mg/kg (M group), or 30 mg/kg (H group) As2O3 for 90 days. The results showed that exposure to As2O3 merely lowered (P < 0.05) the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) in M and H groups at 90 days, significantly downregulated the inhibition ability of hydroxyl radicals (OH·), and upregulated (P < 0.05) the contents of malondialdehyde (MDA) in As2O3 exposure groups at 30, 60, and 90 days. Meanwhile, the messenger RNA levels of inflammatory cytokines (tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and prostaglandin E synthase (PTGEs)) significantly increased (P < 0.05) in As2O3 exposure groups at 30, 60, and 90 days, and histological and ultrastructural damage was observed in As2O3 exposure groups. Additionally, As2O3-induced cardiac enzyme (aspartate transaminase (AST), creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and α-hydroxybutyrate dehydrogenase (α-HBDH)) levels increased (P < 0.05) at 90 days. These findings suggested that As2O3 exposure led to oxidative stress, inflammatory response, and histological and ultrastructural damage and altered the levels of cardiac enzymes in chicken heart tissues. This result may be helpful for further studies on the toxicological mechanisms of As2O3 in the chicken heart.


Assuntos
Galinhas , Coração , Óxidos/toxicidade , Animais , Arsênio , Trióxido de Arsênio , Arsenicais , Catalase , Citocinas , Glutationa Peroxidase , Hidroxibutirato Desidrogenase , Masculino , Malondialdeído , NF-kappa B , Óxido Nítrico Sintase Tipo II , Estresse Oxidativo , Fator de Necrose Tumoral alfa
6.
Neurobiol Dis ; 82: 593-606, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26311408

RESUMO

Late-onset dementia is a major health concern in the ageing population. Alzheimer's disease (AD) accounts for the largest proportion (65-70%) of dementia cases in the older population. Despite considerable research effort, the pathogenesis of late-onset AD remains unclear. Substantial evidence suggests that the neurodegenerative process is initiated by chronic cerebral hypoperfusion (CCH) caused by ageing and cardiovascular conditions. CCH causes reduced oxygen, glucose and other nutrient supply to the brain, with direct damage not only to the parenchymal cells, but also to the blood-brain barrier (BBB), a key mediator of cerebral homeostasis. BBB dysfunction mediates the indirect neurotoxic effects of CCH by promoting oxidative stress, inflammation, paracellular permeability, and dysregulation of nitric oxide, a key regulator of regional blood flow. As such, BBB dysfunction mediates a vicious circle in which cerebral perfusion is reduced further and the neurodegenerative process is accelerated. Endothelial interaction with pericytes and astrocytes could also play a role in the process. Reciprocal interactions between vascular dysfunction and neurodegeneration could further contribute to the development of the disease. A comprehensive overview of the complex scenario of interacting endothelium-mediated processes is currently lacking, and could prospectively contribute to the identification of adequate therapeutic interventions. This study reviews the current literature of in vitro and ex vivo studies on endothelium-mediated mechanisms underlying vascular dysfunction in AD pathogenesis, with the aim of presenting a comprehensive overview of the complex network of causative relationships. Particular emphasis is given to vicious circles which can accelerate the process of neurovascular degeneration.


Assuntos
Doença de Alzheimer/fisiopatologia , Barreira Hematoencefálica/fisiopatologia , Circulação Cerebrovascular/fisiologia , Endotélio Vascular/fisiopatologia , Animais , Humanos
7.
Fish Shellfish Immunol ; 45(2): 321-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25917397

RESUMO

The aquaculture industry for Apostichopus japonicus has suffered severe economic and resource losses due to high temperature in recent summers. There is increasing concern about the effect of high temperature on this species. Histological, ultrastructural and HSP70 responses to heat stress were investigated in the intestine of A. japonicus. Tissue degradation was observed in muscular, submucosal and mucosal layers, with significant decrease in plicae circulares of the mucosal layer. Ultrastructural damage intensified with increasing stress time, and indicators of cell apoptosis were evident after 192 h heat stress. Immunostaining showed HSP70 mainly in mucosa and serosa, with faint staining in non-stressed individuals (the control group) and denser staining under stress (the 6, 48 and 192 h groups). Western blot detection confirmed ocurrence of HSP70 in all groups and significant up-regulation under stress. The rapid and persistent response of HSP70 implies its critical role in the heat shock response of A. japonicus.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Resposta ao Choque Térmico , Stichopus/fisiologia , Regulação para Cima , Animais , Proteínas de Choque Térmico HSP70/metabolismo , Mucosa Intestinal/metabolismo , Stichopus/genética
8.
Invest. clín ; 51(4): 479-488, dic. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-630906

RESUMO

The cell response of human HepG2 cells exposed to hypothermia with rewarming was analyzed. Ultrastructural findings in hypothermic stressed cells showed swollen mitochondria, dispersed chromatin, vacuoles and ring-shape nucleolar reorganization. These changes were coupled with significative differences in the induction of Hsp60, inducible Hsp70 and monomeric Hsf1 in all treated samples, but not in Hsc 70 expression. Cellular response to hypothermia could be associated with the synergistic induction of Hsp expression.


En este trabajo se analizó la respuesta celular de células HepG2 expuestas a hipotermia con posterior recuperación. Los hallazgos ultraestructurales en células sometidas a estrés hipotérmico incluyeron mitocondrias edematizadas, núcleos picnóticos, vacuolas y reorganización nucleolar en forma de anillo. Tales cambios están relacionados con diferencias significativas en la inducción de la expresión de Hsp60, Hsp70 inducible y Hsf 1 monomérico en todas las muestras tratadas, pero no de Hsc70. La respuesta celular a la hipotermia puede ser relacionada con la inducción sinergística de las Hsp.


Assuntos
Humanos , Temperatura Baixa , Carcinoma Hepatocelular/patologia , /biossíntese , Proteínas de Ligação a DNA/biossíntese , Regulação Neoplásica da Expressão Gênica , /biossíntese , Neoplasias Hepáticas/patologia , Proteínas de Neoplasias/biossíntese , Fatores de Transcrição/biossíntese , Linhagem Celular Tumoral/metabolismo , Linhagem Celular Tumoral/ultraestrutura , /genética , Temperatura Baixa/efeitos adversos , Proteínas de Ligação a DNA/genética , /genética , Mitocôndrias/ultraestrutura , Proteínas de Neoplasias/genética , Reaquecimento , Temperatura , Fatores de Transcrição/genética
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