Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Curr Issues Mol Biol ; 46(5): 4186-4202, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38785524

RESUMO

As environmental plastic waste degrades, it creates an abundance of diverse microplastic particles. Consequently, microplastics contaminate drinking water and many staple food products, meaning the oral ingestion of microplastics is an important exposure route for the human population. Microplastics have long been considered inert, however their ability to promote microbial dysbiosis as well as gut inflammation and dysfunction suggests they are more noxious than first thought. More alarmingly, there is evidence for microplastics permeating from the gut throughout the body, with adverse effects on the immune and nervous systems. Coupled with the now-accepted role of the gut-brain axis in neurodegeneration, these findings support the hypothesis that this ubiquitous environmental pollutant is contributing to the rising incidence of neurodegenerative diseases, like Alzheimer's disease and Parkinson's disease. This comprehensive narrative review explores the consequences of oral microplastic exposure on the gut-brain-axis by considering current evidence for gastrointestinal uptake and disruption, immune activation, translocation throughout the body, and neurological effects. As microplastics are now a permanent feature of the global environment, understanding their effects on the gut, brain, and whole body will facilitate critical further research and inform policy changes aimed at reducing any adverse consequences.

2.
Eur J Neurosci ; 57(2): 400-418, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36494087

RESUMO

Traumatic brain injury (TBI) can be a devastating and debilitating disease to endure. Due to improvements in clinical practice, declining mortality rates have led to research into the long-term consequences of TBI. For example, the incidence and severity of TBI have been associated with an increased susceptibility of developing neurodegenerative disorders, such as Parkinson's or Alzheimer's disease. However, the mechanisms linking this alarming association are yet to be fully understood. Recently, there has been a groundswell of evidence implicating the microbiota-gut-brain axis in the pathogenesis of these diseases. Interestingly, survivors of TBI often report gastrointestinal complaints and animal studies have demonstrated gastrointestinal dysfunction and dysbiosis following injury. Autonomic dysregulation and chronic inflammation appear to be the main driver of these pathologies. Consequently, this review will explore the potential role of the microbiota-gut-brain axis in the development of neurodegenerative diseases following TBI.


Assuntos
Lesões Encefálicas Traumáticas , Microbioma Gastrointestinal , Doenças Neurodegenerativas , Animais , Encéfalo , Eixo Encéfalo-Intestino , Lesões Encefálicas Traumáticas/complicações , Doenças Neurodegenerativas/etiologia
3.
BMC Med ; 20(1): 11, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35034660

RESUMO

There is considerable variability in disease progression for patients with amyotrophic lateral sclerosis (ALS) including the age of disease onset, site of disease onset, and survival time. There is growing evidence that short structural variations (SSVs) residing in frequently overlooked genomic regions can contribute to complex disease mechanisms and can explain, in part, the phenotypic variability in ALS patients. Here, we discuss SSVs recently characterized by our laboratory and how these discoveries integrate into the current literature on ALS, particularly in the context of application to future clinical trials. These markers may help to identify and differentiate patients for clinical trials that have a similar ALS disease mechanism(s), thereby reducing the impact of participant heterogeneity. As evidence accumulates for the genetic markers discovered in SQSTM1, SCAF4, and STMN2, we hope to improve the outcomes of future ALS clinical trials.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Progressão da Doença , Marcadores Genéticos/genética , Humanos , Fatores de Processamento de Serina-Arginina
4.
J Strength Cond Res ; 36(2): 573-576, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35080207

RESUMO

ABSTRACT: Jacob, Y, Hart, NH, Cochrane, JL, Spiteri, T, Laws, SM, Jones, A, Rogalski, B, Kenna, J, and Anderton, RS. ACTN3 (R577X) genotype is associated with Australian Football League players. J Strength Cond Res 36(2): 573-576, 2022-Genetic variants in the angiotensin-converting enzyme (ACE) and alpha actinin-3 (ACTN3) genes have been associated with elite sport athletic performance. This study aimed to investigate the frequency of each polymorphism in a cohort of elite Australian football (AF) players. To achieve this, 47 players from an Australian Football League (AFL) club and 59 healthy age matched controls with no history of elite sporting competition were recruited for this study. Each subject provided saliva samples through buccal swab for DNA extraction and genotyping, with group comparisons made using χ2 and odds ratio analysis. There was no significant difference in ACE I/D genotype between healthy control and elite AF players. The ACTN3 XX genotype was significantly underrepresented in AFL players (4.3%) compared with healthy controls (28.8%, p = 0.003). In addition, there was a greater representation of the R allele in elite AF players (70.2%) when compared with healthy controls (50%; χ2 = 8.834, p = 0.002). This is the first study to investigate genetic variants in elite AF players, with results suggesting that the ACTN3 gene may play a significant role explaining aspects of athletic performance in AF.


Assuntos
Desempenho Atlético , Esportes de Equipe , Humanos , Actinina/genética , Atletas , Austrália , Genótipo
5.
Neurochem Res ; 46(5): 1166-1176, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33523394

RESUMO

Poly-arginine peptides R18 and R18D have previously been demonstrated to be neuroprotective in ischaemic stroke models. Here we examined the proteolytic stability and efficacy of R18 and R18D in reducing infarct core growth and preserving the ischaemic penumbra following middle cerebral artery occlusion (MCAO) in the Sprague Dawley rat. R18 (300 or 1000 nmol/kg), R18D (300 nmol/kg) or saline were administered intravenously 10 min after MCAO induced using a filament. Serial perfusion and diffusion-weighted MRI imaging was performed to measure changes in the infarct core and penumbra from time points between 45- and 225-min post-occlusion. Repeated measures analyses of infarct growth and penumbral tissue size were evaluated using generalised linear mixed models (GLMMs). R18D (300 nmol/kg) was most effective in slowing infarct core growth (46.8 mm3 reduction; p < 0.001) and preserving penumbral tissue (21.6% increase; p < 0.001), followed by R18 at the 300 nmol/kg dose (core: 29.5 mm3 reduction; p < 0.001, penumbra: 12.5% increase; p < 0.001). R18 at the 1000 nmol/kg dose had a significant impact in slowing core growth (19.5 mm3 reduction; p = 0.026), but only a modest impact on penumbral preservation (6.9% increase; p = 0.062). The in vitro anti-excitotoxic neuroprotective efficacy of R18D was also demonstrated to be unaffected when preincubated for 1-3 h or overnight, in a cell lysate prepared from dying neurons or with the proteolytic enzyme, plasmin, whereas the neuroprotective efficacy of R18 was significantly reduced after a 2-h incubation. These findings highlight the capacity of poly-arginine peptides to reduce infarct growth and preserve the ischaemic penumbra, and confirm the superior efficacy and proteolytic stability of R18D, which indicates that this peptide is likely to retain its neuroprotective properties when co-administered with alteplase during thrombolysis for acute ischaemic stroke.


Assuntos
Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/uso terapêutico , Animais , Encéfalo/efeitos dos fármacos , Células Cultivadas , Fibrinolisina/metabolismo , Masculino , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Estabilidade Proteica , Ratos Sprague-Dawley , Estereoisomerismo
6.
Neurochem Res ; 45(5): 1215-1229, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32140956

RESUMO

Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) in ischaemic stroke has been associated with neurotoxicity, blood brain barrier (BBB) disruption and intra-cerebral hemorrhage. To examine rtPA cellular toxicity we investigated the effects of rtPA on cell viability in neuronal, astrocyte and brain endothelial cell (bEnd.3) cultures with and without prior exposure to oxygen-glucose deprivation (OGD). In addition, the neuroprotective peptide poly-arginine-18 (R18D; 18-mer of D-arginine) was examined for its ability to reduce rtPA toxicity. Studies demonstrated that a 4- or 24-h exposure of rtPA was toxic, affecting neuronal cell viability at ≥ 2 µM, and astrocyte and bEnd.3 cells viability at ≥ 5 µM. In addition, a 4-h exposure to rtPA after a period of OGD (OGD/rtPA) exacerbated toxicity, affecting neuronal, astrocyte and bEnd.3 cell viability at rtPA concentrations as low as 0.1 µM. Treatment of cells with low concentrations of R18D (0.5 and 1 µM) reduced the toxic effects of rtPA and OGD/rtPA, while on some occasions a higher 2 µM R18D concentrations exacerbated neuronal and bEnd.3 cell toxicity in OGD/rtPA exposed cultures. In exploratory studies we also demonstrated that OGD activates matrix metalloproteinase-9 (MMP-9) release into the supernatant of astrocyte and bEnd.3 cell cultures, but not neuronal cultures, and that OGD/rtPA increases MMP-9 activation. Furthermore, R18D decreased MMP-9 activation in OGD/rtPA treated astrocyte and bEnd.3 cell cultures. In summary, the findings show that rtPA can be toxic to neural cells and that OGD exacerbates toxicity, while R18D has the capacity to reduce rtPA neural cellular toxicity and reduce MMP-9 activation in astrocytes and bEnd.3. Poly-arginine-18 peptides, which are being developed as neuroprotective therapeutics for ischaemic stroke, therefore have the additional potential of reducing cytotoxic effects associated with rtPA thrombolysis in the treatment of ischaemic stroke.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ativador de Plasminogênio Tecidual/toxicidade , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Camundongos , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/toxicidade
7.
Mol Cell Biochem ; 464(1-2): 27-38, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31679100

RESUMO

We have previously demonstrated that Cationic Arginine-Rich Peptides (CARPs) and in particular poly-arginine-18 (R18; 18-mer of arginine) exhibit potent neuroprotective properties in both in vitro and in vivo neuronal injury models. Based on the current literature, there is a consensus that arginine residues by virtue of their positive charge and guanidinium head group is the critical element for imparting CARP neuroprotective properties and their ability to traverse cell membranes. This study examined the importance of guanidinium head groups in R18 for peptide cellular uptake, localization, and neuroprotection. This was achieved by using poly-ornithine-18 (O18; 18-mer of ornithine) as a control, which is structurally identical to R18, but possesses amino head groups rather than guanidino head groups. Epifluorescence and confocal fluorescence microscopy was used to examine the cellular uptake and localization of the FITC-conjugated R18 and O18 in primary rat cortical neurons and SH-SY5Y human neuroblastoma cell cultures. An in vitro cortical neuronal glutamic acid excitotoxicity model was used to compare the effectiveness of R18 and O18 to inhibit cell death and intracellular calcium influx, as well as caspase and calpain activation. Fluorescence imaging studies revealed cellular uptake of both FITC-R18 and FITC-O18 in neuronal and SH-SY5Y cells; however, intracellular localization of the peptides differed in neurons. Following glutamic acid excitotoxicity, only R18 was neuroprotective, prevented caspases and calpain activation, and was more effective at reducing neuronal intracellular calcium influx. Overall, this study demonstrated that for long chain cationic poly-arginine peptides, the guanidinium head groups provided by arginine residues are an essential requirement for neuroprotection but are not required for entry into neurons.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores , Peptídeos , Animais , Linhagem Celular Tumoral , Neurônios/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Peptídeos/química , Peptídeos/farmacocinética , Peptídeos/farmacologia , Ratos , Ratos Sprague-Dawley
8.
Molecules ; 25(13)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610439

RESUMO

Recent studies have highlighted that a novel class of neuroprotective peptide, known as cationic arginine-rich peptides (CARPs), have intrinsic neuroprotective properties and are particularly effective anti-excitotoxic agents. As such, the present study investigated the mechanisms underlying the anti-excitotoxic properties of CARPs, using poly-arginine-18 (R18; 18-mer of arginine) as a representative peptide. Cortical neuronal cultures subjected to glutamic acid excitotoxicity were used to assess the effects of R18 on ionotropic glutamate receptor (iGluR)-mediated intracellular calcium influx, and its ability to reduce neuronal injury from raised intracellular calcium levels after inhibition of endoplasmic reticulum calcium uptake by thapsigargin. The results indicate that R18 significantly reduces calcium influx by suppressing iGluR overactivation, and results in preservation of mitochondrial membrane potential (ΔΨm) and ATP production, and reduced ROS generation. R18 also protected cortical neurons against thapsigargin-induced neurotoxicity, which indicates that the peptide helps maintain neuronal survival when intracellular calcium levels are elevated. Taken together, these findings provide important insight into the mechanisms of action of R18, supporting its potential application as a neuroprotective therapeutic for acute and chronic neurological disorders.


Assuntos
Neurônios/metabolismo , Neuroproteção/efeitos dos fármacos , Peptídeos/farmacologia , Receptores de Glutamato/genética , Animais , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Ácido Glutâmico/química , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Neuroproteção/genética , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Peptídeos/química , Ratos , Receptores de Glutamato/química
9.
Curr Ther Res Clin Exp ; 92: 100584, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322314

RESUMO

BACKGROUND: Despite extensive studies, there are still no clinically available neuroprotective treatments for traumatic brain injury. OBJECTIVES: In previous studies we demonstrated beneficial treatment effects of polyarginine peptides R18 (18-mer of arginine; 300 nmol/kg) and R18D (18-mer of D-arginine; 1000 nmol/kg) in a rat model of impact-acceleration closed-head injury. METHODS: We examined the efficacy of R18D when intravenously administered at a low (100 nmol/kg) and high (1000 nmol/kg) dose, 30 minutes after a closed-head injury in male Sprague-Dawley rats. RESULTS: At postinjury day 3, treatment with R18D at the high dose significantly reduced axonal injury (P = 0.044), whereas the low-dose treatment of R18D showed a trend for reduced axonal injury. Following assessment in the Barnes maze, both doses of R18D treatment appeared to improve learning and memory recovery compared with vehicle treatment at postinjury days 1 and 3, albeit not to a statistically significant level. Rotarod assessment of vestibulomotor recovery did not differ between R18D and the vehicle treatment groups. CONCLUSIONS: R18D modestly decreased axonal injury only at the highest dose used but had no significant effect on functional recovery. These findings warrant further studies with additional doses to better understand peptide pharmacodynamics and provide information to guide optimal dosing.

10.
Neurobiol Dis ; 121: 17-33, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30218759

RESUMO

Stroke is the second leading cause of death globally and represents a major cause of devastating long-term disability. Despite sustained efforts to develop clinically effective neuroprotective therapies, presently there is no clinically available neuroprotective agent for stroke. As a central mediator of neurodamaging events in stroke, mitochondria are recognised as a critical neuroprotective target, and as such, provide a focus for developing mitochondrial-targeted therapeutics. In recent years, cationic arginine-rich peptides (CARPs) have been identified as a novel class of neuroprotective agent with several demonstrated mechanisms of action, including their ability to target mitochondria and exert positive effects on the organelle. This review provides an overview on neuronal mitochondrial dysfunction in ischaemic stroke pathophysiology and highlights the potential beneficial effects of CARPs on mitochondria in the ischaemic brain following stroke.


Assuntos
Arginina/administração & dosagem , Isquemia Encefálica/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Peptídeos/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Isquemia Encefálica/complicações , Isquemia Encefálica/metabolismo , Humanos , Mitocôndrias/metabolismo , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/metabolismo , Resultado do Tratamento
11.
J Exerc Sci Fit ; 17(2): 41-46, 2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-30740132

RESUMO

The current study aimed to determine whether previously identified candidate polymorphisms were associated with match performance in sub-elite Australian Rules Football (ARF) players. The genotypes of thirty players were analysed along with 3x1-kilometre time trial results, ARF-specific skill assessments (handball and kicking), and match performance (direct game involvements) per minute (DGIs/min) to investigate if there was a relationship between any of the variables. Results support previous findings that aerobic time trials are a significant predictor of DGIs/min in sub-elite ARF players. Significant associations were found for genotypes ADRB2 CC (p = .001), PPARGC1A AA (p = .001), PPARGC1A AG (p < .001), ACE ID (p < .001), COMT AA (p = .003), BDNF AG (p = .008), ADRB1 CC (p = .018) and ADRB3 CC (p = .010) and the 3x1-kilometre time trials (p < .001). In the current study, a variant in the DRD2 gene was a strong predictor of handball possessions during a match. Significance was seen for variants in the BDNF and COMT genes when the kicking and handball skill test results were combined and used in a linear mixed model to predict DGIs/min, suggesting a potential relationship with motor learning. The confirmation of genetic predictors of player performance in a team sport, such as ARF, suggests a portion of the physiological mechanisms of skill and ARF-specific talent may be explained by the expression of a specific number of genes.

12.
J Neurosci Res ; 96(11): 1816-1826, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30146697

RESUMO

Hypoxic-ischaemic encephalopathy (HIE) remains the leading cause of mortality and morbidity in neonates, with no available neuroprotective therapeutic agent. In the development of a therapeutic for HIE, we examined the neuroprotective efficacy of the poly-arginine peptide R18D (arginine 18 mer synthesised with D-arginine) in a perinatal model of hypoxia-ischaemia (HI; common carotid and external carotid occlusion + 8%O2 /92%N2 for 2.5 hr) in the P7 Sprague-Dawley rat. R18D was administered intraperitoneally 30 min (doses 10, 30, 100, 300 and 1,000 nmol/kg), 60 min (doses 30 and 300 nmol/kg) or 120 min (doses 30 and 300 nmol/kg) after HI. Infarct volumes and behavioural outcomes were measured 48 hr after HI. When administered 30 min after HI, R18D at varying doses reduced infarct volume by 23.7% to 35.6% (p = 0.009 to < 0.0001) and resulted in improvements in the negative geotactic response and wire-hang times, at a dose of 30 nmol/kg. When administered 60 min after HI, R18D at the 30 nmol/kg dose reduced total infarct volume by 34.2% (p = 0.002), whilst the 300 nmol/kg dose improved wire-hang time. When administered 120 min after HI, R18D at the 30 and 300 nmol/kg doses had no significant impact on infarct volume, but the 300 nmol/kg dose improved the negative geotactic response. This study further confirms the neuroprotective properties of poly-arginine peptides, demonstrating that R18D can reduce infarct volume and improve behavioural outcomes after HI if administered up to 60 min after HI and improve behavioural outcomes up to 2 hr after HI.


Assuntos
Hipóxia-Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Peptídeos/farmacologia , Animais , Infarto Encefálico/tratamento farmacológico , Feminino , Masculino , Neuroproteção , Ratos , Ratos Sprague-Dawley , Reflexo de Endireitamento/efeitos dos fármacos
13.
Mol Cell Biochem ; 426(1-2): 75-85, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27844251

RESUMO

In a recent study, we highlighted the importance of cationic charge and arginine residues for the neuroprotective properties of poly-arginine and arginine-rich peptides. In this study, using cortical neuronal cultures and an in vitro glutamic acid excitotoxicity model, we examined the neuroprotective efficacy of different modifications to the poly-arginine-9 peptide (R9). We compared an unmodified R9 peptide with R9 peptides containing the following modifications: (i) C-terminal amidation (R9-NH2); (ii) N-terminal acetylation (Ac-R9); (iii) C-terminal amidation with N-terminal acetylation (Ac-R9-NH2); and (iv) C-terminal amidation with D-amino acids (R9D-NH2). The three C-terminal amidated peptides (R9-NH2, Ac-R9-NH2, and R9D-NH2) displayed neuroprotective effects greater than the unmodified R9 peptide, while the N-terminal acetylated peptide (Ac-R9) had reduced efficacy. Using the R9-NH2 peptide, neuroprotection could be induced with a 10 min peptide pre-treatment, 1-6 h before glutamic acid insult, or when added to neuronal cultures up to 45 min post-insult. In addition, all peptides were capable of reducing glutamic acid-mediated neuronal intracellular calcium influx, in a manner that reflected their neuroprotective efficacy. This study further highlights the neuroprotective properties of poly-arginine peptides and provides insight into peptide modifications that affect efficacy.


Assuntos
Córtex Cerebral/metabolismo , Ácido Glutâmico/toxicidade , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Peptídeos/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Córtex Cerebral/patologia , Neurônios/patologia , Fármacos Neuroprotetores/química , Peptídeos/química , Ratos
14.
BMC Neurosci ; 17(1): 19, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-27142074

RESUMO

BACKGROUND: We recently reported that poly-arginine peptides have neuroprotective properties both in vitro and in vivo. In cultured cortical neurons exposed to glutamic acid excitotoxicity, we demonstrated that neuroprotective potency increases with polymer length plateauing at R15 to R18 (R = arginine resides). In an in vivo study in rats, we also demonstrated that R9D (R9 peptide synthesised with D-isoform amino acids) administered intravenously at a dose of 1000 nmol/kg 30 min after permanent middle cerebral artery occlusion (MCAO) reduces infarct volume. Based on these positive in vitro and in vivo findings, we decided to examine the neuroprotective efficacy of the L-isoform poly-arginine peptides, R12, R15 and R18 when administered at a dose of 1000 nmol/kg 30 min after permanent MCAO in the rat. RESULTS: At 24 h post-MCAO, there was reduced total infarct volume for R12 (12.8 % reduction) and R18 (20.5 % reduction), but this reduction only reached statistical significance for R18. Brain slice analysis revealed significantly reduced injury in coronal slices 4 and 5 for R18, and slice 5 for R12. The R15 peptide had no effect on infarct volume. Peptide treatment did not reveal any statistical significant improvement in functional outcomes. CONCLUSION: While these findings confirm the in vivo neuroprotective properties of poly-arginine peptides, additional dose studies are required particularly in less severe transient MCAO models so as to further assess the potential of these agents as a stroke therapy.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Fármacos Neuroprotetores/farmacologia , Peptídeos/farmacologia , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Masculino , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Teste de Desempenho do Rota-Rod , Índice de Gravidade de Doença , Redução de Peso/efeitos dos fármacos
15.
Parkinsons Dis ; 2024: 8770997, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766569

RESUMO

Heightened trait impulsivity in both subclinical and pathological senses is becoming increasingly recognised in Parkinson's disease (PD). Impulsive behaviours and impulse control disorders (ICDs) are a consequence of perturbation to the rewards pathway leading individuals to conduct activities in a repetitive, excessive, and maladaptive fashion. Commonly linked to PD, heightened trait impulsivity has been found to primarily manifest in the forms of hypersexuality, pathological gambling, compulsive shopping, and binge eating, all of which may significantly impact social and financial standing. Subsequent burden to quality of life for both individuals with PD and caregivers are common. Although risk factors and indicators for ICDs in PD are currently lacking, it is recognised that the condition is often precipitated by dopamine replacement therapies, primarily dopamine agonist administration. While this nonmotor symptom is being increasingly diagnosed in PD populations, it remains relatively elusive in comparison to its motor counterparts. Through discussion of impulsivity characteristics, neuroanatomy, and neurochemistry, in addition to reviewing existing research on the potential contributing factors to impulsivity in PD, this review highlights impulsivity as a significant and detrimental PD symptom. Thus, emphasising the imperative need to establish efficacious diagnostic tools and treatments.

16.
Biomedicines ; 11(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626586

RESUMO

In Parkinson's disease (PD), gut inflammation is hypothesised to contribute to α-synuclein aggregation, but gastrointestinal α-synuclein expression is poorly characterised. Cationic arginine-rich peptides (CARPs) are an emerging therapeutic option that exerts various neuroprotective effects and may target the transmission of protein aggregates. This study aimed to investigate endogenous α-synuclein expression in enteroendocrine STC-1 cells and the potential of the CARP, R18D (18-mer of D-arginine), to prevent internalisation of pre-formed α-synuclein fibrils (PFFs) in enteroendocrine cells in vitro. Through confocal microscopy, the immunoreactivity of full-length α-synuclein and the serine-129 phosphorylated form (pS129) was investigated in STC-1 (mouse enteroendocrine) cells. Thereafter, STC-1 cells were exposed to PFFs tagged with Alexa-Fluor 488 (PFF-488) for 2 and 24 h and R18D-FITC for 10 min. After confirming the uptake of both PFFs and R18D-FITC through fluorescent microscopy, STC-1 cells were pre-treated with R18D (5 or 10 µM) for 10 min prior to 2 h of PFF-488 exposure. Immunoreactivity for endogenous α-synuclein and pS129 was evident in STC-1 cells, with prominent pS129 staining along cytoplasmic processes and in perinuclear areas. STC-1 cells internalised PFFs, confirmed through co-localisation of PFF-488 and human-specific α-synuclein immunoreactivity. R18D-FITC entered STC-1 cells within 10 min and pre-treatment of STC-1 cells with R18D interfered with PFF uptake. The endogenous presence of α-synuclein in enteroendocrine cells, coupled with their rapid uptake of PFFs, demonstrates a potential for pathogenic spread of α-synuclein aggregates in the gut. R18D is a novel therapeutic approach to reduce the intercellular transmission of α-synuclein pathology.

18.
Sci Rep ; 12(1): 14739, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042248

RESUMO

Neurofilament heavy (NEFH) is one of the critical proteins required for the formation of the neuronal cytoskeleton and polymorphisms in NEFH are reported as a rare cause of sporadic ALS (sALS). In the current study, a candidate tetranucleotide (TTTA) repeat variant in NEFH was selected using an in-silico short structural variant (SSV) evaluation algorithm and investigated in two cohorts of North American sALS patients, both separately and combined (Duke cohort n = 138, Coriell cohort n = 333; combined cohort n = 471), compared to a group of healthy controls from the Coriell Institute biobank (n = 496). Stratification according to site of disease onset revealed that the 9 TTTA allele was associated with reduced disease risk, specifically confined to spinal-onset sALS patients in the Duke cohort (p = 0.001). Furthermore, carriage of the 10 TTTA allele was associated with a 2.7 year later age of disease onset in the larger combined sALS cohort (p = 0.02). These results suggest that the 9 and 10 TTTA motif length may have a protective advantage for potentially lowering the risk of sALS and delaying the age of disease onset, however, these results need to be replicated in larger multicenter and multi-ethnic cohorts.


Assuntos
Esclerose Lateral Amiotrófica , Predisposição Genética para Doença , Proteínas de Neurofilamentos/genética , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/genética , Humanos , Filamentos Intermediários , Mutação , Polimorfismo Genético
19.
Parkinsons Dis ; 2022: 4053665, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466568

RESUMO

Background: Gastrointestinal symptoms (GIS) in people with Parkinson's disease (PwP) are often underreported and may remain untreated. Constipation is a common nonmotor symptom that can adversely affect health-related quality of life (QoL); however, the impact of other GIS has not been adequately investigated. Objectives: To investigate the relationship between QoL and constipation using the Bristol Stool Chart, bowel movement frequency, and a perceived constipation measure; and to explore the relationship between QoL and other GIS in an Australian PD cohort. Methods: The impact of constipation and other GIS on QoL, as measured using the PDQ-39 scale, was assessed in a cohort of 144 (89 males, 55 females) clinic-attending PwP. Constipation was assessed using the Bristol Stool Chart as well as a composite constipation measure, and the Gastrointestinal Symptom Rating Scale (GSRS) was used to rate other GIS. Covariate corrected linear regression models were utilised to determine significant associations between GIS and QoL scores. Results: Individual and combined constipation measures were significantly associated with poorer QoL (p=0.032 and p=0.002, respectively). Analysis of GSRS symptom domains showed that in addition to symptoms of gastrointestinal hypomotility, a number of other symptoms such as increased eructation and increased flatus were also associated with poorer QoL. Conclusions: The findings point to the importance of GIS as contributor to health-related QoL in PwP. A better understanding of the relationship between GIS and QoL will help facilitate the development of more effective screening and treatment programs to improve symptom management and QoL for PwP.

20.
Sports Med Open ; 8(1): 126, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36219268

RESUMO

INTRODUCTION: Australian Football is a dynamic team sport that requires many athletic traits to succeed. Due to this combination of traits, as well as technical skill and physicality, there are many types of injuries that could occur. Injuries are not only a hindrance to the individual player, but to the team as a whole. Many strength and conditioning personnel strive to minimise injuries to players to accomplish team success. PURPOSE: To investigate whether selected polymorphisms have an association with injury occurrence in elite male Australian Football players. METHODS: Using DNA obtained from 46 elite male players, we investigated the associations of injury-related polymorphisms across multiple genes (ACTN3, CCL2, COL1A1, COL5A1, COL12A1, EMILIN1, IGF2, NOGGIN, SMAD6) with injury incidence, severity, type (contact and non-contact), and tissue (muscle, bone, tendon, ligament) over 7 years in one Australian Football League team. RESULTS: A significant association was observed between the rs1372857 variant in NOGGIN (p = 0.023) and the number of total muscle injuries, with carriers of the GG genotype having a higher estimated number of injuries, and moderate, or combined moderate and high severity rated total muscle injuries. The COL5A1 rs12722TT genotype also had a significant association (p = 0.028) with the number of total muscle injuries. The COL5A1 variant also had a significant association with contact bone injuries (p = 0.030), with a significant association being found with moderate rated injuries. The IGF2 rs3213221-CC variant was significantly associated with a higher estimated number of contact tendon injuries per game (p = 0.028), while a higher estimated number of total ligament (p = 0.019) and non-contact ligament (p = 0.002) injuries per game were significantly associated with carriage of the COL1A1 rs1800012-TT genotype. CONCLUSIONS: Our preliminary study is the first to examine associations between genetic variants and injury in Australian Football. NOGGIN rs1372857-GG, COL5A1 rs12722-TT, IGF2 rs3213221-CC, and COL1A1 rs1800012-TT genotypes held various associations with muscle-, bone-, tendon- and ligament-related injuries of differing severities. To further increase our understanding of these, and other, genetic variant associations with injury, competition-wide AFL studies that use more players and a larger array of gene candidates is essential.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA