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1.
Br J Nutr ; 126(2): 253-263, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-33468271

RESUMO

Functional changes in the brain during ageing can alter learning and memory, gait and balance - in some cases leading to early cognitive decline, disability or injurious falls among older adults. Dietary interventions with strawberry (SB) have been associated with improvements in neuronal, psychomotor and cognitive functions in rodent models of ageing. We hypothesised that dietary supplementation with SB would improve mobility and cognition among older adults. In this study, twenty-two men and fifteen women, between the ages of 60 and 75 years, were recruited into a randomised, double-blind, placebo-controlled trial in which they consumed either freeze-dried SB (24 g/d, equivalent to two cups of fresh SB) or a SB placebo for 90 d. Participants completed a battery of balance, gait and cognitive tests at baseline and again at 45 and 90 d of intervention. Significant supplement group by study visit interactions were observed on tests of learning and memory. Participants in the SB group showed significantly shorter latencies in a virtual spatial navigation task (P = 0·020, ηp2 = 0·106) and increased word recognition in the California Verbal Learning test (P = 0·014, ηp2 = 0·159) across study visits relative to controls. However, no improvement in gait or balance was observed. These findings show that the addition of SB to the diets of healthy, older adults can improve some aspects of cognition, but not gait or balance, although more studies with a larger sample size and longer follow-up are needed to confirm this finding.


Assuntos
Disfunção Cognitiva , Dieta , Fragaria , Idoso , Cognição , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Marcha , Humanos , Masculino , Pessoa de Meia-Idade
2.
Nutr Neurosci ; 22(4): 253-263, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28931353

RESUMO

OBJECTIVES: Consuming a high-fat diet (HFD) may result in behavioral deficits similar to those observed in aging animals. Blueberries may prevent and even reverse age-related alterations in neurochemistry and behavior. It was previously demonstrated that middle-aged mice fed HFD had impaired memory; however, supplementation of HFD with blueberry reduced these memory deficits. As a follow-up to that study, the brain tissue from HFD-fed mice with and without blueberry supplementation was assessed to determine the neuroprotective mechanism(s) by which blueberry allayed cognitive dysfunction associated with HFD. METHODS: Mice were fed HFDs (60% calories from fat) or low-fat diets (LFD) with and without 4% blueberry (freeze-dried, U.S. Highbush Blueberry Council). Microglia activation was assessed ex vivo and in vitro. The hippocampus was assessed for brain-derived neurotrophic factor (BDNF) and neurogenesis by measuring doublecortin (DCX). RESULTS: There was significantly less microglia ionized calcium binding adaptor molecule 1 staining and fewer microglia in the brains of mice fed HFD + blueberry compared to mice fed LFD and HFD. BV-2 microglial cells treated with serum collected from the mice fed the diets supplemented with blueberry produced less nitric oxide compared to cells treated with serum from mice fed HFD. BDNF levels were higher and the number of DCX-positive cells was greater in the hippocampus of mice fed HFD + blueberry compared to mice fed HFD. DISCUSSION: This study demonstrated that supplementation of a HFD with blueberry reduced indices of microglia activation and increased neuroplasticity, and these changes may underlie the protection against memory deficits in HFD-fed mice supplemented with blueberry.


Assuntos
Mirtilos Azuis (Planta) , Dieta Hiperlipídica/efeitos adversos , Hipocampo/metabolismo , Microglia/metabolismo , Plasticidade Neuronal , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células , Células Cultivadas , Proteína Duplacortina , Masculino , Camundongos Endogâmicos C57BL , NADPH Oxidase 4/metabolismo , Neurogênese , Óxido Nítrico/metabolismo
3.
Int J Med Sci ; 12(5): 432-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078703

RESUMO

Intermittent hypoxia preconditioning (IHP) has been shown to protect neurons against ischemic stroke injury. Studying how proteins respond to IHP may identify targets that can help fight stroke. The objective of the present study was to investigate whether mitochondrial dihydrolipoamide dehydrogenase (DLDH) would respond to IHP and if so, whether such a response could be linked to neuroprotection in ischemic stroke injury. To do this, we subjected male rats to IHP for 20 days and measured the content and activity of DLDH as well as the three α-keto acid dehydrogenase complexes that contain DLDH. We also measured mitochondrial electron transport chain enzyme activities. Results show that DLDH content was indeed upregulated by IHP and this upregulation did not alter the activities of the three α-keto acid dehydrogenase complexes. Results also show that the activities of the five mitochondrial complexes (I-V) were not altered either by IHP. To investigate whether IHP-induced DLDH upregulation is linked to neuroprotection against ischemic stroke injury, we subjected both DLDH deficient mouse and DLDH transgenic mouse to stroke surgery followed by measurement of brain infarction volume. Results indicate that while mouse deficient in DLDH had exacerbated brain injury after stroke, mouse overexpressing human DLDH also showed increased brain injury after stroke. Therefore, the physiological significance of IHP-induced DLDH upregulation remains to be further investigated.


Assuntos
Isquemia Encefálica/metabolismo , Di-Hidrolipoamida Desidrogenase/metabolismo , Mitocôndrias/metabolismo , Animais , Isquemia Encefálica/patologia , Hipóxia Celular , Di-Hidrolipoamida Desidrogenase/genética , Modelos Animais de Doenças , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Precondicionamento Isquêmico , Camundongos Transgênicos , Ratos , Regulação para Cima
4.
Neurobiol Dis ; 59: 18-25, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23845275

RESUMO

Vascular dementia ranks as the second leading cause of dementia in the United States. However, its underlying pathophysiological mechanism is not fully understood and no effective treatment is available. The purpose of the current study was to evaluate long-term cognitive deficits induced by transient middle cerebral artery occlusion (tMCAO) in rats and to investigate the underlying mechanism. Sprague-Dawley rats were subjected to tMCAO or sham surgery. Behavior tests for locomotor activity and cognitive function were conducted at 7 or 30days after stroke. Hippocampal long term potentiation (LTP) and involvement of GABAergic neurotransmission were evaluated at 30days after sham surgery or stroke. Immunohistochemistry and Western blot analyses were conducted to determine the effect of tMCAO on cell signaling in the hippocampus. Transient MCAO induced a progressive deficiency in spatial performance. At 30days after stroke, no neuron loss or synaptic marker change in the hippocampus were observed. LTP in both hippocampi was reduced at 30days after stroke. This LTP impairment was prevented by blocking GABAA receptors. In addition, ERK activity was significantly reduced in both hippocampi. In summary, we identified a progressive decline in spatial learning and memory after ischemic stroke that correlates with suppression of hippocampal LTP, elevation of GABAergic neurotransmission, and inhibition of ERK activation. Our results indicate that the attenuation of GABAergic activity or enhancement of ERK/MAPK activation in the hippocampus might be potential therapeutic approaches to prevent or attenuate cognitive impairment after ischemic stroke.


Assuntos
Transtornos Cognitivos/etiologia , Regulação da Expressão Gênica/fisiologia , Infarto da Artéria Cerebral Média/complicações , Transdução de Sinais/fisiologia , Animais , Estimulantes do Sistema Nervoso Central/farmacologia , Transtornos Cognitivos/patologia , Modelos Animais de Doenças , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Lateralidade Funcional , Hipocampo/fisiopatologia , Técnicas In Vitro , Masculino , Aprendizagem em Labirinto/fisiologia , Proteínas de Membrana/metabolismo , Atividade Motora/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Picrotoxina/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Percepção Visual/fisiologia
5.
J Res Nurs ; 27(1-2): 68-77, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35392189

RESUMO

Background: Clinical Research Nurses (CRNs) care for study participants and manage clinical research studies; yet the CRN practice role is rarely covered in undergraduate nursing curricula in the United States. Despite a burgeoning need for CRNs, the pipeline of clinical research nurse positions remains sparse. The International Association of Clinical Research Nurses's (IACRN) strategic goal to "engage with nursing schools to heighten awareness and inclusion of the CRN role competencies in nursing education" prompted the development of an educational lecture module to be disseminated to nursing schools. This project is a pilot launch of the module. Methods: A task force of IACRN was formed to develop educational materials that could be used as outreach to undergraduate nursing schools. The content included a slide presentation covering an overview of clinical research, the CRN practice, three embedded videos showing CRN and study participant perspectives, and coverage of the care of participants of research by staff nurses. Due to COVID-19 we revised our live lecture approach using either a live synchronous webinar presentation, or an embedded asynchronous course module with YouTube videos for course learning management systems. We presented the content to 408 nursing students attending three academic programs. To evaluate effectiveness and satisfaction, an anonymous, post-presentation survey using web-based QualtricsXM was distributed to students. Results: Content and delivery of the module was positively evaluated. There was an improvement in knowledge in each topic. Evaluation responses showed that the content could likely or very likely improve care for their patients (87.4%) and improve patient education for patients in clinical trials (95%). Conclusions: Delivering a synchronous or asynchronous module about the CRN practice role to nursing students in academic nursing programs is valuable to increasing awareness of the care of patients in clinical trials, the CRN role, and future professional development.

6.
J Res Nurs ; 27(1-2): 157-165, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35392208

RESUMO

Background: Approximately 25 million people around the world identify as transgender, and the numbers are growing. While visibility of transgender communities has increased, significant healthcare disparities remain. Transgender individuals report being less inclined to share their sex assigned at birth due to fear of stigmatization and mistrust of the medical community. The mistrust and inequity experienced by transgender individuals are not limited to clinical care and may extend to clinical research as well. Aim and method: The aim of this paper is to start a conversation about barriers to participating in research and the role of research staff, specifically the Clinical Research Nurse, in promoting engagement of transgender individuals in clinical research trials. Discussion and conclusions: A discussion of safety considerations, data integrity, and implications for data management is included. Because disparities may result in large part from lack of education and knowledge on best practices for providing care for this population, recommendations for fostering a culture of competence and gender-affirming care among research professionals featuring the role of the research nurse will be discussed.

7.
J Gerontol A Biol Sci Med Sci ; 74(7): 977-983, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-30772901

RESUMO

Daily supplementation of blueberries (BBs) reverses age-related deficits in behavior in aged rats. However, it is unknown whether BB is more beneficial to one subset of the population dependent on baseline cognitive performance and inflammatory status. To examine the effect of individual differences on the efficacy of BB, aged rats (17 months old) were assessed for cognition in the radial arm water maze (RAWM) and divided into good, average, and poor performers based on navigation errors. Half of the rats in each cognitive group were then fed a control or a 2% BB diet for 8 weeks before retesting. Serum samples were collected, pre-diet and post-diet, to assess inflammation. Latency in the radial arm water maze was significantly reduced in the BB-fed poor performers (p < .05) and preserved in the BB-fed good performers. The control-fed good performers committed more working and reference memory errors in the post-test than pretest (p < .05), whereas the BB-fed good performers showed no change. An in vitro study using the serum showed that BB supplementation attenuated lipopolysaccharide (LPS)-induced nitrite and tumor necrosis factor-alpha, and cognitive performance was associated with innate anti-inflammatory capability. Therefore, consumption of BB may reverse some age-related deficits in cognition, as well as preserve function among those with intact cognitive ability.


Assuntos
Envelhecimento , Anti-Inflamatórios , Antioxidantes , Mirtilos Azuis (Planta) , Cognição , Dietoterapia/métodos , Envelhecimento/imunologia , Envelhecimento/psicologia , Animais , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Comportamento Animal , Cognição/efeitos dos fármacos , Cognição/fisiologia , Aprendizagem em Labirinto , Neuroimunomodulação/efeitos dos fármacos , Neuroimunomodulação/fisiologia , Plantas Medicinais , Ratos , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangue
8.
Mech Ageing Dev ; 129(5): 282-90, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18316113

RESUMO

Brain energy metabolism is increased during postnatal development and diminished in neurodegenerative diseases linked to senescence. The objective of this study was to determine if these conditions could involve postnatal or senescence-related shifts in activity or expression of dihydrolipoamide dehydrogenase (DLDH), a key mitochondrial oxidoreductase. Rats ranging from 10 to 60 days of age were used in studies of postnatal development, whereas rats aged 5 or 30 months were used in the aging studies. The expression of DLDH was determined by Western blot analysis using anti-DLDH antibodies and DLDH diaphorase activity was measured by an in-gel activity staining method using nitroblue tetrazolium (NBT)/NADH. Activity of DLDH dehydrogenase was measured as NAD+ oxidation of dihydrolipoamide. When these measures were considered in separate groups of 10-, 20-, 30-, or 60-day-old rats, all three showed an increase between 10 and 20 days of age. However, dehydrogenase activity of DLDH showed a further, progressive increase from 20 days to adulthood, in the absence of any further change in DLDH expression or diaphorase activity. No age-related decline in DLDH activity or expression was evident over the period from 5 to 30 months of age. Moreover, aging did not render DLDH more susceptible to oxidative inactivation by mitochondria-generated reactive oxygen species (ROS). Taken together, results of the present study indicate that (1) brain DLDH expression and activity undergo independent postnatal maturational increases; (2) senescence does not confer any detectable change in the activity of DLDH or its susceptibility to inactivation by mitochondrial oxidative stress.


Assuntos
Envelhecimento/fisiologia , Encéfalo/enzimologia , Encéfalo/crescimento & desenvolvimento , Di-Hidrolipoamida Desidrogenase/metabolismo , Expressão Gênica , Animais , Di-Hidrolipoamida Desidrogenase/genética , Feminino , Masculino , Mitocôndrias/metabolismo , Estresse Oxidativo/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
9.
Nutr Res ; 49: 88-95, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29420996

RESUMO

Diets supplemented with walnuts have shown to protect brain against oxidative and inflammatory cytotoxicity and promote protective cellular and cognitive function. The current study was undertaken to test the hypothesize that whole walnut extract (WNE) inhibits lipopolysaccharide (LPS)-induced microglial activation by regulating calmodulin (CaM) expression through [Ca2+]i. To test this hypothesis, we used an in vitro model the highly aggressively proliferating immortalized cells, a rat microglial cell line, treated with various concentrations of WNEs. Treatment with WNE (1.5%, 3%, or 6%) induced a slow rise in intracellular calcium in a concentration- and time-dependent manner, and this rise became exaggerated when cells were depolarized with potassium chloride (100 mmol/L). Cells treated with WNE (1%, 3%, or 6%) upregulated CaM protein levels, with 1 hour posttreatment being the peak time, regardless of WNE concentration. Interestingly, this WNE-induced upregulation of CaM was blocked by pretreatment with thapsigargin. Additionally, treatment with WNE (1%, 3%, or 6%) 1 hour prior to LPS treatment was found to be effective in preventing LPS-induced upregulation of inducible nitric oxide synthase expression, upregulation of ionized Ca2+-binding adaptor-1, and downregulation of CaM. These findings suggest that bioactive compounds in walnut are capable of modulating microglial activation through regulation of intracellular calcium and CaM expression. Nutritional interventions using walnuts may be effective in the amelioration of chronic inflammation and neurodegeneration.


Assuntos
Encéfalo/efeitos dos fármacos , Cálcio/metabolismo , Calmodulina/metabolismo , Juglans , Microglia/efeitos dos fármacos , Nozes , Extratos Vegetais/farmacologia , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Lipopolissacarídeos , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Cloreto de Potássio/farmacologia , Ratos , Tapsigargina/farmacologia , Regulação para Cima
10.
Food Funct ; 9(1): 96-106, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29318244

RESUMO

Strawberries contain a wide array of nutrients and phytochemicals including polyphenols such as anthocyanins, proanthocyanidins and ellagitannins. These polyphenols are absorbed and metabolized to various phenolic metabolites/conjugates in the body, which may play a role in disease risk reduction. In the present study, we investigated the metabolic fate of strawberry polyphenols after chronic (90 days) supplementation of freeze-dried strawberry (24 g d-1, equivalent to 2 cups of fresh strawberries) vs. control powder in 19 healthy older adults. Blood samples were collected at two time-points i.e., fasting (t = 0 h) and 2 h after the breakfast meal. On days 45 and 90 breakfast also included a control or strawberry drink consistent with their treatment randomization. A total of 21 polyphenolic metabolites were quantified in plasma consisting of 3 anthocyanins/metabolites, 3 urolithin metabolites and 15 phenolic acid metabolites. Among anthocyanins/metabolite, pelargonidin glucuronide (85.7 ± 9.0 nmol L-1, t = 2 h, day 90) was present in the highest concentration. Persistent concentrations of anthocyanins/metabolites, urolithins and some phenolic acids were observed in fasting (t = 0 h) plasma samples on day 45 and 90 after strawberry drink consumption suggesting a role of enteric, enterohepatic recycling or upregulation of gut microbial and/or human metabolism of these compounds. Our results suggest that strawberry polyphenols are absorbed and extensively metabolized, and can persist in the circulation.


Assuntos
Fragaria/metabolismo , Extratos Vegetais/metabolismo , Polifenóis/metabolismo , Idoso , Jejum/sangue , Feminino , Fragaria/química , Frutas/química , Frutas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/sangue , Polifenóis/sangue
11.
J Gerontol A Biol Sci Med Sci ; 72(7): 892-896, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28329224

RESUMO

Frailty is a clinical syndrome that is increasingly prevalent during aging. Frailty involves the confluence of reduced strength, speed, physical activity, and endurance and is associated with adverse health outcomes. The present study adapts existing clinical and preclinical indices of frailty to the Fischer (F344) rat. Male F344 rats (n = 133; 17 mo) completed a battery of behavioral tasks, including forelimb wire suspension (strength), rotarod (speed), open field (physical activity), and inclined screen (endurance). Rats that performed poorly (lowest quintile) on two tasks were considered mildly frail (17.29%, n = 23), and rats that performed poorly on 3-4 tasks were considered frail (2.26%, n = 3). Logistic regression of 100-day survival revealed that mildly frail rats were 3.8 times and frail rats were 27.5 times more likely to die during that period than nonfrail rats (p = .038; 95% confidence interval: 2.030, 372.564). The selected criterion tests, cutoff points, and index provide a potential tool for identifying frailty in aged F344 rats, which is consistent with existing frailty indices for humans and mice.


Assuntos
Envelhecimento/fisiologia , Idoso Fragilizado , Atividade Motora/fisiologia , Condicionamento Físico Animal , Idoso , Animais , Humanos , Modelos Animais , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/fisiologia , Condicionamento Físico Animal/psicologia , Ratos
12.
Exp Gerontol ; 94: 24-28, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28011241

RESUMO

Population aging is leading to an increase in the incidence of age-related cognitive dysfunction and, with it, the health care burden of caring for older adults. Epidemiological studies have shown that consumption of fruits, nuts, and vegetables is positively associated with cognitive ability; however, these foods, which contain a variety of neuroprotective phytochemicals, are widely under-consumed. Surprisingly few studies have investigated the effects of individual plant foods on cognitive health but recent clinical trials have shown that dietary supplementation with individual foods, or switching to a diet rich in several of these foods, can improve cognitive ability. While additional research is needed, increasing fruit, nut, and vegetable intake may be an effective strategy to prevent or delay the onset of cognitive dysfunction during aging.


Assuntos
Transtornos Cognitivos/prevenção & controle , Cognição , Envelhecimento Cognitivo , Dieta Saudável , Frutas , Envelhecimento Saudável , Nozes , Verduras , Fatores Etários , Transtornos Cognitivos/psicologia , Humanos , Fatores de Proteção , Fatores de Risco
13.
Aging Dis ; 8(1): 17-30, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28203479

RESUMO

Metformin is an oral anti-diabetic used as first-line therapy for type 2 diabetes. Because benefits of metformin extend beyond diabetes to other age-related pathology, and because its effect on gene expression profiles resembles that of caloric restriction, metformin has a potential as an anti-aging intervention and may soon be assessed as an intervention to extend healthspan. However, beneficial actions of metformin in the central nervous system have not been clearly established. The current study examined the effect of chronic oral metformin treatment on motor and cognitive function when initiated in young, middle-aged, or old male mice. C57BL/6 mice aged 4, 11, or 22 months were randomly assigned to either a metformin group (2 mg/ml in drinking water) or a control group. The mice were monitored weekly for body weight, as well as food and water intake and a battery of behavioral tests for motor, cognitive and visual function was initiated after the first month of treatment. Liver, hippocampus and cortex were collected at the end of the study to assess redox homeostasis. Overall, metformin supplementation in male mice failed to affect blood glucose, body weights and redox homeostasis at any age. It also had no beneficial effect on age-related declines in psychomotor, cognitive or sensory functions. However, metformin treatment had a deleterious effect on spatial memory and visual acuity, and reduced SOD activity in brain regions. These data confirm that metformin treatment may be associated with deleterious effect resulting from the action of metformin on the central nervous system.

14.
Food Funct ; 8(12): 4752-4759, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29168860

RESUMO

Among older adults, falls are a leading cause of distress, pain, injury, loss of confidence, and ultimately, loss of independence and death. Previous studies in our laboratory have demonstrated that berry supplementation improves the age-related declines in balance, muscle strength, and coordination that often lead to falls, even when initiated later in life. The purpose of this study was to explore the interaction between baseline motor performance and the daily intake of raspberry required to improve/preserve motor function. Aged male F344 (17 mo) rats were tested for baseline (pre-test) balance, muscle strength, and coordination, and divided into good, average, and poor performers based on their motor composite score. Rats in each category were fed with either a control, 1%, or 2% raspberry-supplemented diet for 8 weeks and then retested (post-test). Poor performers fed with 1% or 2% raspberry had higher post-test composite scores (p < 0.05), while 2% raspberry lowered post-test composite scores in the good performers (p < 0.05), compared to control-fed rats. 1% and 2% raspberry appeared to preserve the performance of good performers and improve the performance of poor performers on plank walking (p < 0.05), while 2% raspberry improved post-test grip strength of the poor performers (p < 0.05). Additionally, rats with lower post-diet composite scores had higher levels of serum IL-1ß levels (r = -0.347, p < 0.05). These findings identified poor performers as being the most likely to benefit from daily consumption of ½-2 cups of raspberry to improve/preserve motor function. Therefore, increased raspberry consumption may reduce fall risk, extend independence, and improve quality of life in the aging population.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Atividade Motora , Rubus/metabolismo , Animais , Dieta , Feminino , Frutas/química , Frutas/metabolismo , Humanos , Masculino , Força Muscular , Desempenho Psicomotor , Qualidade de Vida , Ratos , Ratos Endogâmicos F344 , Rubus/química , Caminhada
15.
Biochem Biophys Rep ; 11: 119-129, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28868496

RESUMO

It is well established that NADH/NAD+ redox balance is heavily perturbed in diabetes, and the NADH/NAD+ redox imbalance is a major source of oxidative stress in diabetic tissues. In mitochondria, complex I is the only site for NADH oxidation and NAD+ regeneration and is also a major site for production of mitochondrial reactive oxygen species (ROS). Yet how complex I responds to the NADH/NAD+ redox imbalance and any potential consequences of such response in diabetic pancreas have not been investigated. We report here that pancreatic mitochondrial complex I showed aberrant hyperactivity in either type 1 or type 2 diabetes. Further studies focusing on streptozotocin (STZ)-induced diabetes indicate that complex I hyperactivity could be attenuated by metformin. Moreover, complex I hyperactivity was accompanied by increased activities of complexes II to IV, but not complex V, suggesting that overflow of NADH via complex I in diabetes could be diverted to ROS production. Indeed in diabetic pancreas, ROS production and oxidative stress increased and mitochondrial ATP production decreased, which can be attributed to impaired pancreatic mitochondrial membrane potential that is responsible for increased cell death. Additionally, cellular defense systems such as glucose 6-phosphate dehydrogenase, sirtuin 3, and NQO1 were found to be compromised in diabetic pancreas. Our findings point to the direction that complex I aberrant hyperactivity in pancreas could be a major source of oxidative stress and ß cell failure in diabetes. Therefore, inhibiting pancreatic complex I hyperactivity and attenuating its ROS production by various means in diabetes might serve as a promising approach for anti-diabetic therapies.

16.
Free Radic Biol Med ; 113: 244-254, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29017857

RESUMO

The objective of this study was to investigate a possible role of mitochondrial dihydrolipoamide dehydrogenase (DLDH) as a chemical preconditioning target for neuroprotection against ischemic injury. We used 5-methoxyindole-2-carboxylic acid (MICA), a reportedly reversible DLDH inhibitor, as the preconditioning agent and administered MICA to rats mainly via dietary intake. Upon completion of 4 week's MICA treatment, rats underwent 1h transient ischemia and 24h reperfusion followed by tissue collection. Our results show that MICA protected the brain against ischemic stroke injury as the infarction volume of the brain from the MICA-treated group was significantly smaller than that from the control group. Data were then collected without or with stroke surgery following MICA feeding. It was found that in the absence of stroke following MICA feeding, DLDH activity was lower in the MICA treated group than in the control group, and this decreased activity could be partly due to DLDH protein sulfenation. Moreover, DLDH inhibition by MICA was also found to upregulate the expression of NAD(P)H-ubiquinone oxidoreductase 1(NQO1) via the Nrf2 signaling pathway. In the presence of stroke following MICA feeding, decreased DLDH activity and increased Nrf2 signaling were also observed along with increased NQO1 activity, decreased oxidative stress, decreased cell death, and increased mitochondrial ATP output. We also found that MICA had a delayed preconditioning effect four weeks post MICA treatment. Our study indicates that administration of MICA confers chemical preconditioning and neuroprotection against ischemic stroke injury.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Di-Hidrolipoamida Desidrogenase/genética , Indóis/farmacologia , Proteínas Mitocondriais/genética , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Trifosfato de Adenosina/biossíntese , Administração Oral , Animais , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/enzimologia , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Morte Celular/efeitos dos fármacos , Di-Hidrolipoamida Desidrogenase/antagonistas & inibidores , Di-Hidrolipoamida Desidrogenase/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Precondicionamento Isquêmico , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Acidente Vascular Cerebral/enzimologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia
17.
Age (Dordr) ; 28(3): 297-307, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22253496

RESUMO

Vascular dementia (VaD), incorporating cognitive dysfunction with vascular disease, ranks as the second leading cause of dementia in the United States, yet no effective treatment is currently available. The challenge of defining the pathological substrates of VaD is complicated by the heterogeneous nature of cerebrovascular disease and coexistence of other pathologies, including Alzheimer's disease (AD) types of lesion. The use of rodent models of ischemic stroke may help to elucidate the type of lesions that are responsible for cognitive impairment in humans. Endovascular middle cerebral artery (MCA) occlusion in rats is considered to be a convenient and reliable model of human cerebral ischemia. Both sensorimotor and cognitive dysfunction can be induced in the rat endovascular MCA occlusion model, yet sensorimotor deficits induced by endovascular MCA occlusion may improve with time, whereas data presented in this review suggest that in rats this model can result in a progressive course of cognitive impairment that is consistent with the clinical progression of VaD. Thus far, experimental studies using this model have demonstrated a direct interaction of cerebral ischemic damage and AD-type neuropathologies in the primary ischemic area. Further, coincident to the progressive decline of cognitive function, a delayed neurodegeneration in a remote area, distal to the primary ischemic area, the hippocampus, has been demonstrated in a rat endovascular MCA occlusion model. We argue that this model could be employed to study VaD and provide insight into some of the pathophysiological mechanisms of VaD.

18.
Neuromolecular Med ; 18(3): 465-73, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27166828

RESUMO

Advanced glycation end products (AGEs) are naturally occurring macromolecules that are formed in vivo by the non-enzymatic modification of proteins, lipids, or nucleic acids by sugar, even in the absence of hyperglycemia. In the diet, AGEs are found in animal products, and additional AGEs are produced when those foods are cooked at high temperatures. Studies have linked AGEs to various age-related physiological changes, including wrinkles, diabetic complications, and neurodegenerative disease, including Alzheimer's disease. Dietary berry fruits have been shown to reduce the severity or slow the progression of many physiological changes and disease pathologies that accompany aging. Emerging evidence has shown that the phytochemicals found in berry fruits exhibit anti-glycative activity. In this review, we briefly summarize the current evidence supporting the neuroprotective anti-glycative activity of berry fruits and their potential to preserve cognitive function during aging.


Assuntos
Envelhecimento , Encéfalo/fisiologia , Dieta , Frutas/metabolismo , Doença de Alzheimer/prevenção & controle , Animais , Frutas/química , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Humanos , Doenças Neurodegenerativas/prevenção & controle , Fármacos Neuroprotetores/química
19.
Age (Dordr) ; 38(5-6): 393-404, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27578256

RESUMO

High consumption of fruits and vegetables has been associated with reduced risk of debilitating diseases and improved cognition in aged populations. These beneficial effects have been attributed to the phytochemicals found in fruits and vegetables, which have previously been shown to be anti-inflammatory and modulate autophagy. Tart cherries contain a variety of potentially beneficial phytochemicals; however, little research has been done to investigate the effects of tart cherry on the aging brain. Therefore, the purpose of this study was to determine if tart cherry supplementation can improve cognitive and motor function of aged rats via modulation of inflammation and autophagy in the brain. Thirty 19-month-old male Fischer 344 rats were weight-matched and assigned to receive either a control diet or a diet supplemented with 2 % Montmorency tart cherry. After 6 weeks on the diet, rats were given a battery of behavioral tests to assess for strength, stamina, balance, and coordination, as well as learning and working memory. Although no significant effects were observed on tests of motor performance, tart cherry improved working memory of aged rats. Following behavioral testing, the hippocampus was collected for western/densitometric analysis of inflammatory (GFAP, NOX-2, and COX-2) and autophagy (phosphorylated mTOR, Beclin 1, and p62/SQSTM) markers. Tart cherry supplementation significantly reduced inflammatory markers and improved autophagy function. Daily consumption of tart cherry reduced age-associated inflammation and promoted protein/cellular homeostasis in the hippocampus, along with improvements in working memory. Therefore, addition of tart cherry to the diet may promote healthy aging and/or delay the onset of neurodegenerative diseases.


Assuntos
Envelhecimento , Autofagia , Suplementos Nutricionais , Encefalite/dietoterapia , Hipocampo/fisiologia , Memória de Curto Prazo , Prunus avium/química , Animais , Escala de Avaliação Comportamental , Biomarcadores/análise , Cognição , Masculino , Aprendizagem em Labirinto , Atividade Motora , Pós , Ratos , Ratos Endogâmicos F344 , Fatores de Tempo
20.
Nutr Res ; 35(12): 1079-84, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26475179

RESUMO

Decline in brain function during normal aging is partly due to the long-term effects of oxidative stress and inflammation. Several fruits and vegetables have been shown to possess antioxidant and anti-inflammatory properties. The present study investigated the effects of dietary mushroom intervention on mobility and memory in aged Fischer 344 rats. We hypothesized that daily supplementation of mushroom would have beneficial effects on behavioral outcomes in a dose-dependent manner. Rats were randomly assigned to receive a diet containing either 0%, 0.5%, 1%, 2%, or 5% lyophilized white button mushroom (Agaricus bisporus); after 8 weeks on the diet, a battery of behavioral tasks was given to assess balance, coordination, and cognition. Rats on the 2% or 5% mushroom-supplemented diet consumed more food, without gaining weight, than rats in the other diet groups. Rats in the 0.5% and 1% group stayed on a narrow beam longer, indicating an improvement in balance. Only rats on the 0.5% mushroom diet showed improved performance in a working memory version of the Morris water maze. When taken together, the most effective mushroom dose that produced improvements in both balance and working memory was 0.5%, equivalent to about 1.5 ounces of fresh mushrooms for humans. Therefore, the results suggest that the inclusion of mushroom in the daily diet may have beneficial effects on age-related deficits in cognitive and motor function.


Assuntos
Agaricus , Cognição/efeitos dos fármacos , Dieta , Suplementos Nutricionais , Memória de Curto Prazo/efeitos dos fármacos , Equilíbrio Postural/efeitos dos fármacos , Envelhecimento , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Transtornos Cognitivos/prevenção & controle , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Ratos Endogâmicos F344
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