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1.
Proc Natl Acad Sci U S A ; 120(10): e2214561120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36853940

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped positive stranded RNA virus which has caused the recent deadly pandemic called COVID-19. The SARS-CoV-2 virion is coated with a heavily glycosylated Spike glycoprotein which is responsible for attachment and entry into target cells. One, as yet unexploited strategy for preventing SARS-CoV-2 infections, is the targeting of the glycans on Spike. Lectins are carbohydrate-binding proteins produced by plants, algae, and cyanobacteria. Some lectins can neutralize enveloped viruses displaying external glycoproteins, offering an alternative therapeutic approach for the prevention of infection with virulent ß-coronaviruses, such as SARS-CoV-2. Here we show that the cyanobacterial lectin cyanovirin-N (CV-N) can selectively target SARS-CoV-2 Spike oligosaccharides and inhibit SARS-CoV-2 infection in vitro and in vivo. CV-N neutralizes Delta and Omicron variants in vitro better than earlier circulating viral variants. CV-N binds selectively to Spike with a Kd as low as 15 nM and a stoichiometry of 2 CV-N: 1 Spike but does not bind to the receptor binding domain (RBD). Further mapping of CV-N binding sites on Spike shows that select high-mannose oligosaccharides in the S1 domain of Spike are targeted by CV-N. CV-N also reduced viral loads in the nares and lungs in vivo to protect hamsters against a lethal viral challenge. In summary, we present an anti-coronavirus agent that works by an unexploited mechanism and prevents infection by a broad range of SARS-CoV-2 strains.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Oligossacarídeos/farmacologia , Lectinas
2.
Int J Mol Sci ; 22(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34830402

RESUMO

Lipids are closely associated with brain structure and function. However, the potential changes in the lipidome induced by aging remain to be elucidated. In this study, we used chromatographic techniques and a mass spectrometry-based approach to evaluate age-associated changes in the lipidome of the frontal cortex and cerebellum obtained from adult male Wistar rats (8 months), aged male Wistar rats (26 months), and aged male Wistar rats submitted to a methionine restriction diet (MetR)-as an anti-aging intervention-for 8 weeks. The outcomes revealed that only small changes (about 10%) were observed in the lipidome profile in the cerebellum and frontal cortex during aging, and these changes differed, in some cases, between regions. Furthermore, a MetR diet partially reversed the effects of the aging process. Remarkably, the most affected lipid classes were ether-triacylglycerols, diacylglycerols, phosphatidylethanolamine N-methylated, plasmalogens, ceramides, and cholesterol esters. When the fatty acid profile was analyzed, we observed that the frontal cortex is highly preserved during aging and maintained under MetR, whereas in the cerebellum minor changes (increased monounsaturated and decreased polyunsaturated contents) were observed and not reversed by MetR. We conclude that the rat cerebellum and frontal cortex have efficient mechanisms to preserve the lipid profile of their cell membranes throughout their adult lifespan in order to maintain brain structure and function. A part of the small changes that take place during aging can be reversed with a MetR diet applied in old age.


Assuntos
Envelhecimento/genética , Lobo Frontal/metabolismo , Lipídeos/genética , Metionina/metabolismo , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Cerebelo/metabolismo , Cerebelo/patologia , Cromatografia , Lobo Frontal/patologia , Humanos , Lipidômica/normas , Espectrometria de Massas , Estresse Oxidativo/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo
3.
CNS Neurol Disord Drug Targets ; 23(3): 395-401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36944623

RESUMO

INTRODUCTION: Vortioxetine is a multimodal antidepressant drug that has been reported to have a positive impact on cognition, social function, and fatigue. Nevertheless, it has not been widely studied. Our objective was to explore the effects of vortioxetine on these and other parameters in patients with multiple sclerosis (MS) and depression. PATIENTS AND METHODOLOGY: This observational case series study included patients with MS and depression who received treatment with vortioxetine for at least 6 months. The patient history of depression and depressive symptoms was assessed. A neuropsychiatric evaluation was carried out using different scales, both before and after treatment. RESULTS: Of the 25 patients who enrolled in the study, 17 completed the treatment. Significant improvements were observed in health status (EQ-5D; p = 0.002), mood (Beck's Depression Inventory, BDI-II; p = 0.006), anxiety (State-Trait Anxiety Inventory, STAI-State; p = 0.021, and STAI-Trait; p = 0.011), and in the general health test (Short Form Health Survey, SF-36) for the vitality (p = 0.028) and mental health (p = 0.025) domains of the patients who completed the treatment. However, no statistically significant differences were observed in the cognitive tests related to attention, information processing speed, or fatigue. CONCLUSION: In this population, vortioxetine treatment was effective in reducing the symptoms of depression and improving anxiety, vitality, and mental health. In contrast, it did not produce any improvement in cognition or fatigue but an increase in sample size would be necessary to confirm these results.


Assuntos
Esclerose Múltipla , Humanos , Vortioxetina/uso terapêutico , Vortioxetina/farmacologia , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Depressão/tratamento farmacológico , Depressão/psicologia , Cognição , Fadiga/tratamento farmacológico , Fadiga/etiologia
4.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38675419

RESUMO

Multiple sclerosis (MS) is an autoimmune disease characterized by demyelination and neuroinflammation, often accompanied by cognitive impairment. This study aims (1) to investigate the potential of glatiramer acetate (GA) as a therapy for preventing cognitive decline in patients with MS (pwMS) by modulating oxidative stress (OS) and (2) to seek out the differences in cognition between pwMS in a cohort exhibiting good clinical evolution and control subjects (CS). An exploratory, prospective, multicentre, cross-sectional case-control study was conducted, involving three groups at a 1:1:1 ratio-41 GA-treated pwMS, 42 untreated pwMS, and 42 CS. The participants performed a neuropsychological battery and underwent venepuncture for blood sampling. The inclusion criteria required an Expanded Disability Status Scale score of ≤3.0 and a minimum of 5 years of MS disease. Concerning cognition, the CS had a better performance than the pwMS (p = <0.0001), and between those treated and untreated with GA, no statistically significant differences were found. Regarding oxidation, no statistically significant differences were detected. Upon categorizing the pwMS into cognitively impaired and cognitively preserved groups, the lactate was elevated in the pwMS with cognitive preservation (p = 0.038). The pwMS exhibited a worse cognitive performance than the CS. The pwMS treated with GA did not show an improvement in oxidation. Lactate emerged as a potential biomarker for cognitive preservation.

5.
J Clin Med ; 11(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35566632

RESUMO

Background: Disease-modifying therapies (DMTs) used to treat multiple sclerosis (MS) alter the immune system and therefore increase the risk of infection. There is growing concern about the impact of COVID-19 on patients with MS (pwMS), especially those treated with DMTs. Methods: This is a single-center prospective observational study based on data from the Esclerosis Múltiple y COVID-19 (EMCOVID-19) study. Demographic characteristics, MS history, laboratory data and SARS-CoV-2 serology, and symptoms of COVID-19 in pwMS treated with any DTM were extracted. The relationship among demographics, MS status, DMT, and COVID-19 was evaluated. Results: A total of 259 pwMS were included. The administration of interferon was significantly associated with the presence of SARS-CoV-2 antibodies (26.4% vs. 10.7%, p = 0.006). Although patients taking interferon were significantly older (49.1 vs. 43.5, p = 0.003), the association of interferon with the presence of SARS-CoV-2 antibodies was still significant in the multivariate analysis (OR 2.99 (1.38; 6.36), p = 0.006). Conclusions: According to our data, pwMS present a higher risk of COVID-19 infection compared with results obtained from the general population. There is no evidence of a worse COVID-19 outcome in pwMS. DMTs did not significantly change the frequency of COVID-19, except for interferon; however, these findings must be interpreted with caution given the small sample of pwMS taking each DMT.

6.
Front Neurosci ; 13: 938, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551694

RESUMO

Literature suggests that oxidative stress (OS) may be involved in the pathogenesis of multiple sclerosis (MS), in which the immune system is known to play a key role. However, to date, the OS in peripheral lymphocytes and its contribution to the disease remain unknown. The aim of the present study was to explore the influence of OS in peripheral lymphocytes of MS patients. To that end, a cross-sectional, observational pilot study was conducted [n = 58: 34 MS and 24 healthy subjects (control group)]. We have measured superoxide production and protein mitochondrial complex levels in peripheral blood mononuclear cells (PBMCs) isolated from MS patients and control. Lactate levels and the antioxidant capacity were determined in plasma. We adjusted the comparisons between study groups by age, sex and cell count according to case. Results demonstrated that PBMCs, specifically T cells, from MS patients exhibited significantly increased superoxide anion production compared to control group (p = 0.027 and p = 0.041, respectively). Increased superoxide production in PBMCs was maintained after the adjustment (p = 0.044). Regarding mitochondrial proteins, we observe a significant decrease in the representative protein content of the mitochondrial respiratory chain complexes I-V in PBMCs of MS patients (p = 0.002, p = 0.037, p = 0.03, p = 0.044, and p = 0.051, respectively), which was maintained for complexes I, III, and V after the adjustment (p = 0.026; p = 0.033; p = 0.033, respectively). In MS patients, a trend toward increased plasma lactate concentration was detected [8.04 mg lactate/dL (5.25, 9.49) in the control group, 11.36 mg lactate/dL (5.41, 14.81) in MS patients] that was statistically significant after the adjustment (p = 0.013). This might be indicative of compromised mitochondrial function. Finally, antioxidant capacity was also decreased in plasma from MS patients, both before (p = 0.027) and after adjusting for sex and age (p = 0.006). Our findings demonstrate that PBMCs of MS patients show impaired mitochondrial redox status and deficient antioxidant capacity. These results demonstrate for the first time the existence of mitochondrial alterations in the cells immune cells of MS patients already at the peripheral level.

7.
J Gerontol A Biol Sci Med Sci ; 73(6): 703-710, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28958038

RESUMO

Fatty acids are key components in the structural diversity of lipids and play a strategic role in the functional properties of lipids which determine the structural and functional integrity of neural cell membranes, the generation of lipid signaling mediators, and the chemical reactivity of acyl chains. The present study analyzes the profile of lipid fatty acid composition of membranes of human frontal cortex area 8 in individuals ranging from 40 to 90 years old. Different components involved in polyunsaturated fatty acid biosynthesis pathways, as well as adaptive defense mechanisms involved in the lipid-mediated modulation of inflammation, are also assessed. Our results show that the lipid profile in human frontal cortex is basically preserved through the adult life span to decay at advanced ages, which is accompanied by an adaptive proactive anti-inflammatory response possibly geared to ensuring cell survival and function.


Assuntos
Envelhecimento/metabolismo , Ácidos Graxos/metabolismo , Lobo Frontal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Cadáver , Cromatografia Gasosa , Humanos , Inflamação/metabolismo , Longevidade , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
8.
Phys Rev E ; 96(6-1): 062604, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29347351

RESUMO

Micron-sized particles (microbeads) dispersed in a suspension of magnetic nanoparticles, i.e., ferrofluids, can be assembled into different types of structures upon application of an external magnetic field. This paper is devoted to theoretical modeling of a relative motion of a pair of microbeads (either soft ferromagnetic or diamagnetic) in the ferrofluid under the action of applied uniform magnetic field which induces magnetic moments in the microbeads making them attracting to each other. The model is based on a point-dipole approximation for the magnetic interactions between microbeads mediated by the ferrofluid; however, the ferrofluid is considered to possess an anisotropic magnetic permeability thanks to field-induced structuring of its nanoparticles. The model is tested against experimental results and shows generally better agreement with experiments than the model considering isotropic magnetic permeability of ferrofluids. The results could be useful for understanding kinetics of aggregation of microbeads suspended in a ferrofluid. From a broader perspective, the present study is believed to contribute to a general understanding of particle behaviors in anisotropic media.

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