RESUMEN
In this review, I discuss current knowledge and outstanding questions on the neuromodulators that influence aggressive behavior of the fruit fly Drosophila melanogaster. I first present evidence that Drosophila exchange information during an agonistic interaction and choose appropriate actions based on this information. I then discuss the influence of several biogenic amines and neuropeptides on aggressive behavior. One striking characteristic of neuromodulation is that it can configure a neural circuit dynamically, enabling one circuit to generate multiple outcomes. I suggest a consensus effect of each neuromodulatory molecule on Drosophila aggression, as well as effects of receptor proteins where relevant data are available. Lastly, I consider neuromodulation in the context of strategic action choices during agonistic interactions. Genetic components of neuromodulatory systems are highly conserved across animals, suggesting that molecular and cellular mechanisms controlling Drosophila aggression can shed light on neural principles governing action choice during social interactions.
Asunto(s)
Agresión/fisiología , Conducta Animal/fisiología , Encéfalo/metabolismo , Drosophila melanogaster/fisiología , Neurotransmisores/fisiología , AnimalesRESUMEN
Communication is inherently social, so signaling systems should evolve with social systems. The 'social complexity hypothesis' posits that social complexity necessitates communicative complexity and is generally supported in vocalizing mammals. This hypothesis, however, has seldom been tested outside the acoustic modality, and comparisons across studies are confounded by varying definitions of complexity. Moreover, proximate mechanisms underlying coevolution of sociality and communication remain largely unexamined. In this review, we argue that to uncover how sociality and communication coevolve, we need to examine variation in the neuroendocrine mechanisms that coregulate social behavior and signal production and perception. Specifically, we focus on steroid hormones, monoamines, and nonapeptides, which modulate both social behavior and sensorimotor circuits and are likely targets of selection during social evolution. Lastly, we highlight weakly electric fishes as an ideal system in which to comparatively address the proximate mechanisms underlying relationships between social and signal diversity in a novel modality.
Asunto(s)
Evolución Biológica , Conducta Social , Animales , Sistemas Neurosecretores/fisiología , Comunicación , MamíferosRESUMEN
Recent studies show that pathogenic variants in DNAJC12, a co-chaperone for monoamine synthesis, may cause mild hyperphenylalaninemia with infantile dystonia, young-onset parkinsonism, developmental delay and cognitive deficits. DNAJC12 has been included in newborn screening, most revealingly in Spain, and those results highlight the importance of genetic diagnosis and early intervention in combating human disease. However, practitioners may be unaware of these advances and it is probable that many patients, especially adults, have yet to receive molecular testing for DNAJC12. Hence, this review summarizes genotype-phenotype relationships and treatment paradigms for patients with pathogenic variants in DNAJC12. It provides an overview of the structure of DNAJC12 protein, known genetic variants, domains, and binding partners, and elaborates on its role in monoamine synthesis, disease etiology, and pathogenesis. © 2023 International Parkinson and Movement Disorder Society.
Asunto(s)
Trastornos del Movimiento , Trastornos Parkinsonianos , Fenilcetonurias , Adulto , Humanos , Recién Nacido , Aminas , Trastornos del Movimiento/genética , Trastornos Parkinsonianos/genética , Fenilcetonurias/genética , Fenilcetonurias/patología , Proteínas Represoras/genéticaRESUMEN
One of the most prevalent axes of behavioral variation in both humans and animals is risk taking, where individuals that are more willing to take risk are characterized as bold while those that are more reserved are regarded as shy. Brain monoamines (i.e. serotonin, dopamine and noradrenaline) have been found to play a role in a variety of behaviors related to risk taking. Using zebrafish, we investigated whether there was a relationship between monoamine function and boldness behavior during exploration of a novel tank. We found a correlation between serotonin metabolism (5-HIAA:5-HT ratio) and boldness during the initial exposure to the tank in female animals. The DOPAC:DA ratio correlated with boldness behavior on the third day in male fish. There was no relationship between boldness and noradrenaline. To probe differences in serotonergic function in bold and shy fish, we administered a selective serotonin reuptake inhibitor, escitalopram, and assessed exploratory behavior. We found that escitalopram had opposing effects on thigmotaxis in bold and shy female animals: the drug caused bold fish to spend more time near the center of the tank and shy fish spent more time near the periphery. Taken together, our findings indicate that variation in serotonergic function has sex-specific contributions to individual differences in risk-taking behavior.
Asunto(s)
Individualidad , Serotonina , Pez Cebra , Animales , Pez Cebra/fisiología , Pez Cebra/metabolismo , Femenino , Serotonina/metabolismo , Masculino , Conducta Exploratoria/efectos de los fármacos , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Citalopram/farmacología , Conducta Animal/efectos de los fármacos , Asunción de Riesgos , Dopamina/metabolismo , Ácido Hidroxiindolacético/metabolismoRESUMEN
Research on anxiety faces challenges due to the wide range of symptoms, making it difficult to determine if different aspects of anxiety are linked to distinct neurobiological processes. Both alterations in functional brain connectivity (FC) and monoaminergic neurotransmitter systems are implicated as potential neural bases of anxiety. We aimed to investigate whole-brain FC involving monoaminergic nuclei and its association with anxiety dimensions in 178 non-clinical participants. Nine anxiety-related scales were used, encompassing trait and state anxiety scores, along with measures of cost-probability, hypervigilance, reward-punishment sensitivity, uncertainty, and trait worry. Resting-state functional magnetic resonance imaging data were acquired, focusing on seven brainstem regions representing serotonergic, dopaminergic, and noradrenergic nuclei, with their FC patterns voxel-wise correlated with the scales. All models underwent family-wise-error correction for multiple comparisons. We observed intriguing relationships: trait and state anxiety scores exhibited opposing correlations in FC between the dorsal raphe nucleus and the paracingulate gyrus. Additionally, we identified shared neural correlates, such as a negative correlation between the locus coeruleus and the frontal pole. This connection was significantly associated with scores on measures of probability, hypervigilance, reward sensitivity, and trait worry. These findings underscore the intricate interplay between anxiety dimensions and subcortico-cortical FC patterns, shedding light on the underlying neural mechanisms governing anxiety.
RESUMEN
OBJECTIVES: Reports indicate that children of mothers who received docosahexaenoic acid (DHA) or egg yolk supplements during pregnancy have improved performance on cognitive tasks and brain growth; their combination has recently been demonstrated to modulate functional neuronal network connectivity in the human-relevant piglet brain. To expand upon this functional connectivity analysis, neurochemical evaluation to determine how dietary supplementation with one or both of these nutrients during the last trimester of pregnancy alters monoamine homeostasis in selected brain regions of piglets was done. METHODS: Beginning gestation days 60-69 through weaning, pregnant sows were fed either control diet or diets supplemented with egg yolk powder, DHA, or both. Brains were then collected, and monoamine neurotransmitters and their metabolites were quantified from various brain regions with HPLC-ECD. RESULTS: Relative to controls, egg yolk supplementation increased serotonin metabolite (5-HIAA) levels in the cerebellum, while DHA supplementation decreased serotonin (5-HT) levels in the prefrontal cortex; combined supplementation increased norepinephrine metabolite (MHPG) levels in the prefrontal cortex and cerebellum, but decreased 5-HT levels in the posterior hippocampus. Notably, all diets increased serotonin, dopamine, and their respective metabolite levels in the substantia nigra. DISSCUSSION: This suggests both overlapping and specific effects of DHA and components of egg yolk in the context of maternal supplementation during pregnancy and lactation that might facilitate optimal neurodevelopment, with the nigrostriatal pathway being particularly sensitive. Such supplementations might impact brain function and facilitate development later in life through modulating monoamine homeostasis.
RESUMEN
Several recent studies have attempted to understand how fasting has benefits for body health, especially the nervous system. To evaluate the impact of intermittent fasting on body weight, brain neurotransmitters, brain oxidative stress, and brain-derived neurotrophic factor (BDNF) in several areas of the brain, this study was conducted in rats. Thirty male Wistar rats were randomly divided into two groups. Group 1 (15 rats) served as the control and group 2 (15 rats) underwent intermittent fasting (IF; 24 h) for 1, 7, or 15 days. The findings demonstrated that intermittent fasting significantly reduced body weight. In this sense, brain monoamines and amino acids, namely dopamine, glutamate, aspartate, and oxidative stress markers (malondialdehyde and nitric oxide), decreased significantly after 1 day of IF. However, norepinephrine, serotonin, gamma-amino butyric acid, and glycine increased significantly. Additionally, glutathione levels were markedly elevated in IF. Surprisingly, the neuromodulatory effect of intermittent fasting fluctuates depending on the IF period. To support this fluctuation, BDNF levels increased after 1 day in the hippocampus and decreased after 15 days of intermittent fasting in all areas of the brain tested. In conclusion, our results show that intermittent fasting has beneficial influences on the brain; however, prolonged intermittent fasting can also induce some unfavorable physiological outcomes that prevent optimal neurological function.
Asunto(s)
Antioxidantes , Factor Neurotrófico Derivado del Encéfalo , Encéfalo , Ayuno , Neurotransmisores , Estrés Oxidativo , Ratas Wistar , Animales , Masculino , Ayuno/metabolismo , Neurotransmisores/metabolismo , Encéfalo/metabolismo , Ratas , Estrés Oxidativo/fisiología , Antioxidantes/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Oxidantes/metabolismo , Peso Corporal/fisiología , Ayuno IntermitenteRESUMEN
Fish oil has been known for its antioxidant, cardioprotective, anti-inflammatory, and neuroprotective characteristics due to the presence of polyunsaturated fatty acids (PUFAs) that are essential for optimal brain function and mental health. The present study investigated the effect of Carcharhinus Bleekeri (Shark Fish) oil on learning and memory functions in scopolamine-induced amnesia in rats. Locomotor and memory-enhancing activity in scopolamine-induced amnesic rats was investigated by assessing the open field and passive avoidance paradigm. Forty male Albino mice were divided into 4 equal groups (n = 10) as bellow: 1 - control (received 0.9% saline), 2 - SCOP (received scopolamine 2 mg/kg for 21 days), 3 - SCOP + SFO (received scopolamine and fish oil 5 mg/kg/ day for 21 days), 4 - SCOP + Donepezil groups (received 3 mg/kg/day for 21 days). SFO produced significant (P < 0.01) locomotor and memory-enhancing activities in open-field and passive avoidance paradigm models. Additionally, SFO restored the Acetylcholine (ACh) concentration in the hippocampus (p < 0.05) and remarkably prevented the degradation of monoamines. Histology of brain tissue showed marked cellular distortion in the scopolamine-treated group, while the SFO treatment restored distortion in the brain's hippocampus region. These results suggest that the SFO significantly ameliorates scopolamine-induced spatial memory impairment by attenuating the ACh and monoamine concentrations in the rat's hippocampus.
Asunto(s)
Aceites de Pescado , Escopolamina , Animales , Masculino , Ratones , Ratas , Acetilcolina/farmacología , Aceites de Pescado/farmacología , Hipocampo/metabolismo , Aprendizaje por Laberinto , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/prevención & control , Modelos TeóricosRESUMEN
This study aimed to prepare defatted ethanol extract of Abelmoschus esculentus leaves, Morus nigra leaves and Punica granatum peel, to identify the chemical composition of these extracts and to explore their efficacy in counteracting diabetic neuropathy. LC-ESI-MS spectrometry was the hyphenated tool for component identification of these extracts. Behavioral, biochemical, and histopathological investigations were carried out after treatments of diabetic rats. The phenolic contents in the extracts are 16.38, 34.75 and 40.57â mg GAE/g extract regarding A. esculentus leaves, M. nigra leaves and P. granatum peel respectively. Chemodiversity of the phenolic contents was observed from the LC/Mass, where A. esculentus extract contained isoflavonoids and flavanones, M. nigra extract consisted of benzofurans, prenylated flavonoids, stilbenes, and xanthones, and P. granatum extract was rich in ellagitanins, condensed tannins, and anthocyanins. The extracts normalize of blood glucose levels, enhance the explorative behavior of the rats and their response time to thermal pain, restore the oxidant/antioxidant balance, attenuate inflammation, augment brain monoamines levels and modulate MAO-A and Ache enzyme activity. Furthermore, they recovered brain histopathological alterations. Conclusively, this study offers experimental evidence for the neuroprotective impact of studied defatted ethanol extracts against diabetic neuropathy via their hypoglycemic effect, antioxidant activity, and anti-inflammatory potential.
RESUMEN
The monoaminergic neurotransmitter 5-hydroxytryptamine (5-HT) is known to be involved in several physiological, behavioural and neuroendocrine functions in vertebrates. In this study, we investigated the distribution of 5-HT neuronal system in the central nervous system (CNS) of Sphaerotheca breviceps tadpoles at metamorphic climax stage. In the telencephalon, there was no 5-HT-immunoreactive (5-HT-ir) perikarya, but conspicuous fibres were observed in the olfactory bulb, pallium, subpallium and amygdala complexes. The preoptic area showed dense 5-HT-ir somata and cerebrospinal fluid contacting fibres, whereas a few varicose 5-HT-ir fibres were noticed in the suprachiasmatic nucleus. 5-HT-ir cells and fibres were found in the ventral, lateral dorsal subdivisions of the hypothalamus and in the nucleus tuberculi posterioris, but only 5-HT-ir fibres were localised in the periventricular area and pituitary gland. Numerous 5-HT-ir cells and/or fibres were detected in the thalamus, entopeduncular area and mesencephalic subdivisions. In the rhombencephalon, although 5-HT-ir cells and fibres were noticed in the subdivisions of the raphe nucleus and reticular formation, a moderate plexus of fibres was observed in the cerebellum, parabrachial nucleus and solitary tract. Distinct 5-HT-ir fibres, but no perikarya, were observed in the rostral spinal cord. Overall, extensively labelled 5-HT-ir cells and fibres in the CNS of the metamorphic tadpole suggest possible roles for the involvement of 5-HT in various somatosensory, behavioural and neuroendocrine functions during final stages of development.
Asunto(s)
Encéfalo , Mesencéfalo , Animales , Larva , Rombencéfalo , Sistema Nervioso CentralRESUMEN
This Cerebellar Classic highlights the landmark discovery of the innervation of the cerebellar cortex and cerebellar nuclei by noradrenergic and serotoninergic axons emanating, respectively, from the locus coeruleus and the raphé nuclei. Since then, modulation of the activity of cerebellar neurons by the monoamine systems has been studied extensively, as well as their reorganization and modifications during development, plasticity, and disease. The discovery of noradrenergic and serotoninergic innervation of the cerebellum has been a crucial step in understanding the neurochemical relationships between brainstem nuclei and the cerebellum, and the attempts to treat cerebellar ataxias pharmacologically. The large neurochemical repertoire of the cerebellum represents one of the complexities and challenges in the modern appraisal of cerebellar disorders.
Asunto(s)
Tronco Encefálico , Cerebelo , Locus Coeruleus/fisiología , Corteza Cerebelosa , Núcleos Cerebelosos , NorepinefrinaRESUMEN
Social isolation (SI) is chronic psycho-emotional stress for humans and other socially living species. There are few comparative studies that have measured monoamine levels in brain structures in male and female rats subjected to SI. Existing data is highly controversial. In our recent study, we investigated behavioral effects of SI prolonged up to 9 months on a rather large sample of 69 male and female Wistar rats. In the present study, we measured the levels of monoamines-norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT), and DA and 5-HT metabolites-in the brain structures of 40 rats from the same sample. The single-housed rats of both sexes showed hyperactivity and reduced reactivity to novelty in the Open Field test, and impaired passive avoidance learning. Regardless of their sex, by the time of sacrifice, the single-housed rats weighed less and had lower pain sensitivity and decreased anxiety compared with group-housed animals. SI decreased NE levels in the hippocampus and increased them in the striatum. SI induced functional activation of the DA-ergic system in the frontal cortex and hypothalamus, with increased DA and 3-methoxytyramine levels. SI-related changes were found in the 5-HT-ergic system: 5-HT levels increased in the frontal cortex and striatum, while 5-hydroxyindoleacetic acid only increased in the frontal cortex. We believe that SI prolonged for multiple months could be a valuable model for comparative analysis of the behavioral alterations and the underlying molecular processes in dynamics of adaptation to chronic psychosocial stress in male and female rats in relation to age-dependent changes.
Asunto(s)
Encéfalo , Aislamiento Social , Masculino , Femenino , Animales , Ratas , Ratas Wistar , Monoaminas Biogénicas/metabolismo , Encéfalo/metabolismo , Conducta Animal , Aprendizaje por Laberinto , Peso Corporal , AnsiedadRESUMEN
Background: Childhood malnutrition can have devastating consequences on health, behavior, and cognition. Edible insects are sustainable low cost high protein and iron nutritious foods that can prevent malnutrition. However, it is unclear whether insect-based diets may help prevent changes to brain neurochemistry associated with malnutrition.Materials and Methods: Weanling male Sprague-Dawley rats were malnourished by feeding a low protein-iron diet (LPI, 5% protein and â¼2â ppm Fe) for 3 weeks or nourished by feeding a sufficient protein-iron diet (SPI, 15% protein 20â ppm FeSO4) for the duration of the study. Following 3 weeks of LPI diet, three subsets of the malnourished rats were placed on repletion diets supplemented with cricket, palm weevil larvae, or the SPI diet for 2 weeks, while the remaining rats continued the LPI diet for an additional 2 weeks. Monoamine-related neurochemicals (e.g. serotonin (5-HT), dopamine (DA), norepinephrine) and select monoamine metabolites were measured in the hypothalamus, hippocampus, striatum, and prefrontal cortex using Ultra High-Performance Liquid Chromatography.Results: Five weeks of LPI diets disrupted brain monoamines, most notable in the hypothalamus. Two weeks supplementation with cricket and palm weevil larvae diets prevented changes to measures of 5-HT and DA turnover in the hippocampus and hypothalamus. Moreover, these insect diets prevented the malnutrition-induced imbalance of 5-HT and DA metabolites in the hippocampus, striatum, and hypothalamus.Conclusion: Edible insects such as cricket and palm weevil larvae could be sustainable nutrition intervention to prevent behavioral and cognitive impairment associated abnormal brain monoamine activities that results from early life malnutrition.
Asunto(s)
Insectos Comestibles , Desnutrición , Ratas , Animales , Masculino , Insectos Comestibles/metabolismo , Serotonina/metabolismo , Ratas Sprague-Dawley , Encéfalo/metabolismo , Desnutrición/complicaciones , Desnutrición/metabolismo , Dopamina/metabolismo , Norepinefrina/metabolismo , Hierro/metabolismoRESUMEN
Objectives: Both iron and omega-3 (n-3) fatty acids (FA) play important roles in the development and functioning of the brain. We investigated the effects of n-3 FA and iron deficiencies, alone and in combination, during early development on behaviour and brain monoamines in rats. Methods: Using a 2-factorial design, female Wistar rats were randomly allocated to one of four diet groups: Control, n-3 FA deficient (n-3 FAD), iron deficient (ID), or n-3 FAD + ID. Females received these diets throughout mating, pregnancy and lactation. Offspring (n = 24/group; male:female = 1:1) continued on the same diet until post-natal day 42-45, and underwent a sucrose preference test (SPT), novel object recognition test, elevated plus maze (EPM) and social interaction test (SIT). Results: ID offspring consumed less sucrose in the SPT and spent more time in closed arms and less time in open arms of the EPM than non-ID offspring. In female offspring only, ID and n-3 FAD reduced time approaching and together in the SIT, with an additive effect of ID and n-3 FAD for even less time approaching and spent together in the n-3 FAD + ID group compared to controls. ID offspring had higher striatal dopamine and norepinephrine and lower frontal cortex dopamine concentrations. N-3 FAD and ID affected frontal cortex serotonin concentrations in a sex-specific manner. Conclusions: Our results suggest that ID and n-3 FAD during early development provoke anhedonia, anxiety and social dysfunction in rats, with potential additive and attenuating effects when combined. These effects may in part be attributed to disturbances in brain neurochemistry and may be sex-specific.
RESUMEN
Parkinson's disease (PD) is the second most prevalent neurodegenerative disease worldwide and represents a challenge for clinicians. The present study aims to investigate the effects of cerebrolysin and/or lithium on the behavioral, neurochemical and histopathological alterations induced by reserpine as a model of PD. The rats were divided into control and reserpine-induced PD model groups. The model animals were further divided into four subgroups: rat PD model, rat PD model treated with cerebrolysin, rat PD model treated with lithium and rat PD model treated with a combination of cerebrolysin and lithium. Treatment with cerebrolysin and/or lithium ameliorated most of the alterations in oxidative stress parameters, acetylcholinesterase and monoamines in the striatum and midbrain of reserpine-induced PD model. It also ameliorated the changes in nuclear factor-kappa and improved the histopathological picture induced by reserpine. It could be suggested that cerebrolysin and/or lithium showed promising therapeutic potential against the variations induced in the reserpine model of PD. However, the ameliorating effects of lithium on the neurochemical, histopathological and behavioral alterations induced by reserpine were more prominent than those of cerebrolysin alone or combined with lithium. It can be concluded that the antioxidant and anti-inflammatory effects of both drugs played a significant role in their therapeutic potency.
Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Ratas , Masculino , Animales , Reserpina/farmacología , Ratas Wistar , Litio , Acetilcolinesterasa , Modelos Animales de EnfermedadRESUMEN
Methylphenidate (MPD), known as Ritalin, is a psychostimulant used to treat children, adults, and the elderly. MPD exerts its effects through increasing concentrations of dopamine (DA), norepinephrine (NE), and serotonin (5-HT) in the synaptic cleft. Concomitant behavioral and neuronal recording from the ventral tegmental area (VTA), locus coeruleus (LC), and from the dorsal raphe (DR) nucleus, which are the sources of DA, NE, and 5-HT to the mesocorticolimbic circuit, were investigated following acute and repetitive (chronic) saline, 0.6, 2.5, or 10.0 mg/kg MPD. Animals received daily saline or MPD administration on experimental days 1 to 6 (ED1-6), followed by a 3-day washout period and MPD rechallenge on ED10. Each chronic MPD dose elicits behavioral sensitization in some animals while inducing behavioral tolerance in others. The uniqueness of this study is in the evaluation of neuronal activity based on the behavioral response to chronic MPD. Neuronal excitation was observed mainly in brain areas of animals exhibiting behavioral sensitization, while neuronal attenuation following chronic MPD was observed in animals expressing behavioral tolerance. Different ratios of excitatory/inhibitory neuronal responses were obtained from the VTA, LC, or DR following chronic MPD. Thus, each brain area responds differently to each MPD dose used, suggesting that DA, NE, and 5-HT in the VTA, LC, and DR exert different effects.
Asunto(s)
Metilfenidato , Humanos , Niño , Ratas , Animales , Anciano , Metilfenidato/farmacología , Serotonina/farmacología , Área Tegmental Ventral , Dopamina/farmacología , Núcleo Dorsal del Rafe , Locus Coeruleus , Norepinefrina/farmacología , Ratas Sprague-DawleyRESUMEN
Over the last decade, the zebrafish has emerged as an important model organism for behavioural studies and neurological disorders, as well as for the study of metabolic diseases. This makes zebrafish an alternative model for studying the effects of energy disruption and nutritional quality on a wide range of behavioural aspects. Here, we used the zebrafish model to study how obesity induced by overfeeding regulates emotional and cognitive processes. Two groups of fish (n = 24 per group) were fed at 2% (CTRL) and 8% (overfeeding-induced obesity, OIO) for 8 weeks and tested for anxiety-like behaviour using the novel tank diving test (NTDT). Fish were first tested using a short-term memory test (STM) and then trained for four days for a long-term memory test (LTM). At the end of the experiment, fish were euthanised for biometric sampling, total lipid content, and triglyceride analysis. In addition, brains (eight per treatment) were dissected for HPLC determination of monoamines. Overfeeding induced faster growth and obesity, as indicated by increased total lipid content. OIO had no effect on anxiety-like behaviour. Animals were then tested for cognitive function (learning and memory) using the aversive learning test in Zantiks AD units. Results show that both OIO and CTRL animals were able to associate the aversive stimulus with the conditioned stimulus (conditioned learning), but OIO impaired STM regardless of fish sex, revealing the effects of obesity on cognitive processes in zebrafish. Obese fish did not show a deficiency in monoaminergic transmission, as revealed by quantification of total brain levels of dopamine and serotonin and their metabolites. This provides a reliable protocol for assessing the effect of metabolic disease on cognitive and behavioural function, supporting zebrafish as a model for behavioural and cognitive neuroscience.
Asunto(s)
Cognición , Pez Cebra , Animales , Pez Cebra/fisiología , Obesidad/complicaciones , Ansiedad/etiología , Triglicéridos/farmacología , Conducta AnimalRESUMEN
L-DOPA, the precursor of catecholamines, exerts a pro-locomotor action in several vertebrate species, including newborn rats. Here, we tested the hypothesis that decreasing the degradation of monoamines can promote the pro-locomotor action of a low, subthreshold dose of L-DOPA in five-day-old rats. The activity of the degrading pathways involving monoamine oxidases or catechol-O-methyltransferase was impaired by injecting nialamide or tolcapone, respectively. At this early post-natal stage, the capacity of the drugs to trigger locomotion was investigated by monitoring the air-stepping activity expressed by the animals suspended in a harness above the ground. We show that nialamide (100 mg/kg) or tolcapone (100 mg/kg), without effect on their own promotes maximal expression of air-stepping sequences in the presence of a sub-effective dose of L-DOPA (25 mg/kg). Tissue measurements of monoamines (dopamine, noradrenaline, serotonin and some of their metabolites) in the cervical and lumbar spinal cord confirmed the regional efficacy of each inhibitor toward their respective enzyme. Our experiments support the idea that the raise of monoamines boost L-DOPA's locomotor action. Considering that both inhibitors differently altered the spinal monoamines levels in response to L-DOPA, our data also suggest that maximal locomotor response can be reached with different monoamines environment.
Asunto(s)
Catecol O-Metiltransferasa , Levodopa , Ratas , Animales , Levodopa/farmacología , Levodopa/metabolismo , Tolcapona/farmacología , Animales Recién Nacidos , Nialamida , LocomociónRESUMEN
Currently, the efficacy of drug therapy for post-traumatic stress disorder or PTSD leaves much to be desired, making nutraceutical support a promising avenue for treatment. Recent research has identified the protective effects of resveratrol in PTSD. Here, we tested the behavioral and neurobiological effects of combining cheese consumption with resveratrol supplements in an experimental PTSD model. Using the elevated plus maze test, we observed that cheese intake resulted in a shift from anxiety-like behavior to depressive behavior, evident in increased freezing acts. However, no significant changes in the anxiety index value were observed. Interestingly, supplementation with cheese and resveratrol only led to the elimination of freezing behavior in half of the PTSD rats. We further segregated the rats into two groups based on freezing behavior: Freezing+ and Freezing0 phenotypes. Resveratrol ameliorated the abnormalities in Monoamine Oxidize -A and Brain-Derived Neurotrophic Factor gene expression in the hippocampus, but only in the Freezing0 rats. Moreover, a negative correlation was found between the number of freezing acts and the levels of Monoamine Oxidize-A and Brain-Derived Neurotrophic Factor mRNAs in the hippocampus. The study results show promise for resveratrol supplementation in PTSD treatment. Further research is warranted to better understand the underlying mechanisms and optimize the potential benefits of resveratrol supplementation for PTSD.
Asunto(s)
Queso , Trastornos por Estrés Postraumático , Animales , Ratas , Trastornos por Estrés Postraumático/tratamiento farmacológico , Factor Neurotrófico Derivado del Encéfalo/genética , Resveratrol/farmacología , Resveratrol/uso terapéutico , Aminas , Suplementos DietéticosRESUMEN
Huntington's disease (HD) is a neurodegenerative genetic disorder characterized by motor, psychiatric, cognitive, and peripheral symptoms without effective therapy. Evidence suggests that lifestyle factors can modulate disease onset and progression, and environmental enrichment (EE) has emerged as a potential approach to mitigate the progression and severity of neurodegenerative processes. Wild-type (WT) and yeast artificial chromosome (YAC) 128 mice were exposed to different EE conditions. Animals from cohort 1 were exposed to EE between postnatal days 21 and 60, and animals from cohort 2 were exposed to EE between postnatal days 60 and 120. Motor and non-motor behavioral tests were employed to evaluate the effects of EE on HD progression. Monoamine levels, hippocampal cell proliferation, neuronal differentiation, and dendritic arborization were also assessed. Here we show that EE had an antidepressant-like effect and slowed the progression of motor deficits in HD mice. It also reduced monoamine levels, which correlated with better motor performance, particularly in the striatum. EE also modulated neuronal differentiation in the YAC128 hippocampus. These results confirm that EE can impact behavior, hippocampal neuroplasticity, and monoamine levels in YAC128 mice, suggesting this could be a therapeutic strategy to modulate neuroplasticity deficits in HD. However, further research is needed to fully understand EE's mechanisms and long-term effects as an adjuvant therapy for this debilitating condition.