RESUMO
Environmental enrichment is considered as a recommended tool to guarantee or improve the welfare of captive fish. This study demonstrates for the first time that structural environmental enrichment enhances cognition, exploratory behaviour and brain physiological functions of gilthead seabream (Sparus aurata). Seabream was reared in groups (n = 15) during 60 days under two different treatments: enriched tanks with plant-fibre ropes (EE) or bare/non-enriched tanks (NE). Fish were then exposed to a purpose-built maze for 1 h every second day in four trials. Analysis of video recordings showed that seabream under EE conditions presented higher overall exploratory behaviour, spatial orientation and learning capability compared to seabream from NE conditions. Results from brain monoamines analyses may suggest increased recent dopaminergic activity in telencephalon, known to be involved in learning processes; and increased serotonergic activity in cerebellum, involved in the coordination of balance, movements and orientation. In addition, EE-reared fish showed increased antioxidant activity in whole brain, with no apparent oxidative damage. Structural EE seemed to induce an hormetic response on juvenile seabream, improving their welfare status during captivity. Application of this kind of physical structure might be feasible at fish farms as a passive and non-invasive tool to improve welfare of intensively cultured seabream.
Assuntos
Comportamento Animal , Encéfalo/fisiologia , Comportamento Exploratório , Dourada/fisiologia , Criação de Animais Domésticos/métodos , Animais , Antioxidantes/metabolismo , Cognição , Dopamina/metabolismo , Meio Ambiente , Peixes , Análise Multivariada , Estresse Oxidativo , Serotonina/metabolismo , Telencéfalo/fisiologiaRESUMO
Polyphenols are secondary metabolites widely distributed in many plant foods, such a tea, coffee, chocolate and fruits. The consumption of these compounds is related to the improvement or amelioration of many diseases, including diabetes. Nevertheless, the great barrier to the therapeutic use of polyphenols is the low bioavailability of these compounds once ingested. For that reason, the encapsulation of polyphenols in different matrices may protect them from digestion and improve their release and subsequent absorption to obtain target-specific health effects. Some studies have reported the beneficial effect of encapsulation to increase both bioavailability and bioaccessibility. However, these works have mostly been carried out in vitro and few studies are specifically addressed at improving diabetes. In the current work, an overview of the knowledge related to nanoparticles and their use in the diabetic condition has been reviewed.
Assuntos
Diabetes Mellitus/terapia , Polifenóis/farmacocinética , Animais , Antioxidantes/análise , Antioxidantes/farmacocinética , Disponibilidade Biológica , Cacau/química , Café/química , Gerenciamento Clínico , Modelos Animais de Doenças , Medicina Baseada em Evidências , Frutas/química , Humanos , Hipoglicemiantes/análise , Hipoglicemiantes/farmacocinética , Nanopartículas/química , Polímeros/química , Polifenóis/análise , Substâncias Protetoras/análise , Substâncias Protetoras/farmacocinética , Chá/químicaRESUMO
The increased number of elderly people worldwide poses a major medical and socio-economic challenge: the search of strategies to combat the consequences of the aging process. Oxidative stress and inflammation have been pointed out as the leading causes of brain aging, which in turn alters the functionality of brain. In this context, decline in adult neurogenesis (AN), due to modifications in the neural progenitor stem cells (NSCs) and their microenvironment, is among the aging alterations contributing to cognitive decline. Therefore, the consumption or administration of antioxidant and anti-inflammatory molecules, such as dietary polyphenols, is under study as a potential beneficial strategy for preventing brain aging alterations including AN decline. Polyphenols, through their antioxidant and anti-inflammatory properties, modulate several cascades and effectors involved in the regulation of AN (e.g., SIRT1, Wnt, NF-κB and Nrf2, among others). This work summarizes the latest discoveries regarding the mechanisms whereby polyphenols preserve AN and counteract the cognitive decline present in aging.
Assuntos
Envelhecimento/fisiologia , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Polifenóis/farmacologia , Animais , Cognição/fisiologia , Humanos , Neurogênese/fisiologia , Estresse Oxidativo/efeitos dos fármacosRESUMO
BACKGROUND: Classically the oxidative stress and more recently inflammatory processes have been identified as the major causes of brain aging. Oxidative stress and inflammation affect each other, but there is more information about the effects of oxidative stress on aging than regarding the contribution of inflammation on it. METHODS: In the intense research for methods to delay or mitigate the effects of aging, are interesting polyphenols, natural molecules synthesized by plants (e.g. resveratrol). Their antioxidant and anti-inflammatory properties make them useful molecules in the prevention of aging. RESULTS: The antiaging effects of polyphenols could be due to several related mechanisms, among which are the prevention of oxidative stress, SIRT1 activation and inflammaging modulation, via regulation of some signaling pathways, such as NF-κB. CONCLUSION: In this review, we describe the positive effects of polyphenols on the prevention of the changes that occur during aging in the brain and their consequences on cognition, emphasizing the possible modulation of inflammaging by polyphenols through a SIRT1-mediated mechanism.
Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Sirtuína 1/metabolismo , Estilbenos/farmacologia , Animais , Humanos , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/química , Polifenóis/metabolismo , Polifenóis/farmacologia , ResveratrolRESUMO
Polyphenols have beneficial neurological effects delaying cognitive and motor decline in aging due to their antioxidant, antiinflammatory and neuroprotective properties. These effects could be related to SIRT1 activation (implicated in synaptic plasticity, memory and inflammation) and monoaminergic synthesis modulation. In this work, we studied in old male rats, the in vivo effects of long-term administration of different polyphenols (silymarin, quercetin and naringenin; 20 mg/kg/day i.p, 4 weeks) (Sprague-Dawley, 18 months) on cognition and motor coordination. We also analyzed in different brain regions: tryptophan hydroxylase (TPH) and tyrosine hydroxylase (TH) activities, which mediate central monoaminergic neurotransmitters synthesis; and immunoreactivities of SIRT1 and NF-κB (total and acetylated forms). Results indicated that chronic polyphenolic treatments showed restorative effects on cognition and motor coordination consistently with the biochemical and molecular results. Polyphenols reversed the age-induced deficits in monoaminergic neurotransmitters (serotonin, noradrenaline, and dopamine), increasing TPH and TH activity. In addition, polyphenolic treatments increased SIRT1 levels and decreased NF-κB levels in hippocampus. These results confirm polyphenolic treatments as a valuable potential therapeutic strategy for attenuating inflamm-aging and brain function decline.
Assuntos
Envelhecimento/efeitos dos fármacos , Cognição/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Monoaminas Biogênicas/biossíntese , Flavanonas/farmacologia , Hipocampo/metabolismo , Masculino , Desempenho Psicomotor/efeitos dos fármacos , Quercetina/farmacologia , Ratos , Ratos Sprague-Dawley , Silimarina/farmacologia , Sirtuína 1/biossínteseRESUMO
OBJECTIVE: Staphylococcus aureus is a particularly difficult pathogen to eradicate from the respiratory tract. Previous studies have highlighted the intracellular capacity of S.aureus in several phagocytic and non-phagocytic cells. The aim of this study was to define S.aureus interaction within a murine alveolar macrophage cell line. METHODS: Cell line MH-S was infected with Newman strain. Molecular mechanisms involved in phagocytosis were explored. To assess whether S.aureus survives intracellularly quantitative (gentamicin protection assays and bacterial plating) and qualitative analysis (immunofluorescence microscopy) were performed. Bacterial colocalization with different markers of the endocytic pathway was examined to characterize its intracellular trafficking. RESULTS: We found that S.aureus uptake requires host actin polymerization, microtubule assembly and activation of phosphatidylinositol 3-kinase signaling. Time course experiments showed that Newman strain was able to persist within macrophages at least until 28.5 h post infection. We observed that intracellular bacteria are located inside an acidic subcellular compartment, which co-localizes with the late endosome/lysosome markers Lamp-1, Rab7 and RILP. Colocalization counts with TMR-dextran might reflect a balance between bacterial killing and intracellular survival. CONCLUSIONS: This study indicates that S.aureus persists and replicates inside murine alveolar macrophages, representing a privileged niche that can potentially offer protection from antimicrobial activity and immunological host defense mechanisms.
Assuntos
Macrófagos Alveolares/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Animais , Linhagem Celular , Macrófagos Alveolares/imunologia , Camundongos , Viabilidade Microbiana , Fagocitose , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Resveratrol is a polyphenol exhibiting antioxidant and neuroprotective effects in neurodegenerative diseases. However, neuroprotective properties during normal aging have not been clearly demonstrated. We analyzed the in vivo effects of chronic administration of resveratrol (20 mg/kg/day for 4 weeks) in old male rats (Wistar, 20 months), on tryptophan hydroxylase (TPH) and tyrosine hydroxylase (TH) activities which mediate central monoaminergic neurotransmitters synthesis, and besides, on hippocampal-dependent working memory test (radial maze). Our results show an age-related decline in neurochemical parameters that were reversed by resveratrol administration. The resveratrol treatment enhances serotonin (5-HT) levels in pineal gland, in hippocampus, and in striatum, and those of noradrenaline (NA) in hippocampus and also dopamine (DA) in striatum. These changes were largely due to an increased activity of TPH-1 (463 % in pineal gland), TPH-2 (70-51 % in hippocampus and striatum), and TH (150-36 % in hippocampus and striatum). Additionally, the observed hippocampal effects correlate with a resveratrol-induced restorative effect on working memory (radial maze). In conclusion, this study suggests resveratrol treatment as a restoring therapy for the impaired cognitive functions occurring along normal aging process, by preventing 5-HT, DA, and NA neurotransmission decline.
Assuntos
Envelhecimento/efeitos dos fármacos , Cognição/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão , Masculino , Ratos , Ratos Wistar , Resveratrol , Estilbenos/administração & dosagem , Triptofano Hidroxilase/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
Pineal melatonin is important not only for synchronization of biological rhythms, but also in the ageing process as a potential drug to relieve oxidative damage. During ageing, the nocturnal melatonin production decreases resulting in an increased incidence of disorders. Present in vivo experiments were performed to study the effects of exogenous melatonin chronically administered to old rats on the pineal biosynthesis of melatonin and the precursor serotonin (5-HT) mediated by tryptophan hydroxylase type 1 (TPH-1). Accumulation of 5-hydroxytryptophan (5-HTP) after decarboxylase inhibition was used as a measure of the TPH-1 activity. 5-HT and its metabolite 5-HIAA were also quantified by HPLC-ED. As expected, ageing resulted in worsening of different neurochemical parameters. However, chronic intake of melatonin (1mg/kg/day, diluted in drinking water, 4 weeks) increased TPH-1 activity and significantly improved the age-induced deficits in nocturnal melatonin content in the pineal gland. Results suggest that melatonin intake (or melatonin rich foods) may contribute to recover the pineal function preventing the nocturnal descent of 5-HT and melatonin biosynthesis that normally occur in pineal gland as a consequence of ageing.
Assuntos
Envelhecimento/metabolismo , Antioxidantes/farmacologia , Melatonina/farmacologia , Glândula Pineal/efeitos dos fármacos , Triptofano Hidroxilase/efeitos dos fármacos , Envelhecimento/fisiologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos/métodos , Masculino , Melatonina/administração & dosagem , Melatonina/biossíntese , Glândula Pineal/metabolismo , Glândula Pineal/fisiologia , Ratos , Ratos Sprague-Dawley , Serotonina/biossíntese , Triptofano Hidroxilase/metabolismoRESUMO
This commentary is referred to the review signed by Rattemborg [N.C. Rattenborg, Evolution of slow wave sleep and palliopallial connectivity in mammals and birds. A hypothesis. Brain Res. Bull. 69 (2006) 20-29]. We propose that the review missed important aspects in relation to the characteristics of sleep in poikilotherm vertebrates and in the evolution of sleep. Poikilotherms continuously show an EEG dominated by slow waves, but its highest amplitude appears not during sleep, but during active waking. In addition, they show an arousal reaction which consists in an increase in EEG amplitude and synchrony, opposite to mammals and birds. As a consequence, most of the conclusions proposed in the review should be rejected.