RESUMEN
Copper is a trace element whose electronic configuration provides it with essential structural and catalytic functions. However, in excess, both its high protein affinity and redox-catalyzing properties can lead to hazardous consequences. In addition to promoting oxidative stress, copper is gaining interest for its effects on neurotransmission through modulation of GABAergic and glutamatergic receptors and interaction with the dopamine reuptake transporter. The aim of the present study was to investigate the effects of copper overexposure on the levels of dopamine, noradrenaline, and serotonin, or their main metabolites in rat's striatum extracellular fluid. Copper was injected intraperitoneally using our previously developed model, which ensured striatal overconcentration (2 mg CuCl2/kg for 30 days). Subsequently, extracellular fluid was collected by microdialysis on days 0, 15, and 30. Dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and noradrenaline (NA) levels were then determined by HPLC coupled with electrochemical detection. We observed a significant increase in the basal levels of DA and HVA after 15 days of treatment (310% and 351%), which was maintained after 30 days (358% and 402%), with no significant changes in the concentrations of 5-HIAA, DOPAC, and NA. Copper overload led to a marked increase in synaptic DA concentration, which could contribute to the psychoneurological alterations and the increased oxidative toxicity observed in Wilson's disease and other copper dysregulation states.
Asunto(s)
Cobre , Cuerpo Estriado , Dopamina , Líquido Extracelular , Ácido Homovanílico , Animales , Dopamina/metabolismo , Cobre/metabolismo , Ácido Homovanílico/metabolismo , Ratas , Masculino , Líquido Extracelular/metabolismo , Cuerpo Estriado/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ratas Wistar , Serotonina/metabolismo , Norepinefrina/metabolismoRESUMEN
BACKGROUND: Computational mining of useful enzymes and biosynthesis pathways is a powerful strategy for metabolic engineering. Through systematic exploration of all conceivable combinations of enzyme reactions, including both known compounds and those inferred from the chemical structures of established reactions, we can uncover previously undiscovered enzymatic processes. The application of the novel alternative pathways enables us to improve microbial bioproduction by bypassing or reinforcing metabolic bottlenecks. Benzylisoquinoline alkaloids (BIAs) are a diverse group of plant-derived compounds with important pharmaceutical properties. BIA biosynthesis has developed into a prime example of metabolic engineering and microbial bioproduction. The early bottleneck of BIA production in Escherichia coli consists of 3,4-dihydroxyphenylacetaldehyde (DHPAA) production and conversion to tetrahydropapaveroline (THP). Previous studies have selected monoamine oxidase (MAO) and DHPAA synthase (DHPAAS) to produce DHPAA from dopamine and oxygen; however, both of these enzymes produce toxic hydrogen peroxide as a byproduct. RESULTS: In the current study, in silico pathway design is applied to relieve the bottleneck of DHPAA production in the synthetic BIA pathway. Specifically, the cytochrome P450 enzyme, tyrosine N-monooxygenase (CYP79), is identified to bypass the established MAO- and DHPAAS-mediated pathways in an alternative arylacetaldoxime route to DHPAA with a peroxide-independent mechanism. The application of this pathway is proposed to result in less formation of toxic byproducts, leading to improved production of reticuline (up to 60 mg/L at the flask scale) when compared with that from the conventional MAO pathway. CONCLUSIONS: This study showed improved reticuline production using the bypass pathway predicted by the M-path computational platform. Reticuline production in E. coli exceeded that of the conventional MAO-mediated pathway. The study provides a clear example of the integration of pathway mining and enzyme design in creating artificial metabolic pathways and suggests further potential applications of this strategy in metabolic engineering.
Asunto(s)
Bencilisoquinolinas , Escherichia coli , Ingeniería Metabólica , Ingeniería Metabólica/métodos , Bencilisoquinolinas/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Vías Biosintéticas , Simulación por Computador , Tetrahidropapaverolina/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ácido 3,4-Dihidroxifenilacético/análogos & derivadosRESUMEN
Formosan wood mice (Apodemus semotus) are endemic rodents in Taiwan. Recently Formosan wood mice exhibit similar locomotor behaviors in the laboratory environment as in the field environment has shown. Contemporaneously, Formosan wood mice have higher moving distances of and central dopaminergic (DAergic) activities than C57BL/6 mice in behavioral test. This study tried to compare the behavioral responses between male Formosan wood mice and male C57BL/6 mice in the light-dark exploration tests. We also measured the levels of DA and 3,4-dihydroxyphenylacetic acid (DOPAC), the primary metabolite of DA, to assess the dopaminergic activity of the medial prefrontal cortex, striatum, and nucleus accumbens. Our data show that Formosan wood mice revealed higher exploration and central DAergic activities than did C57BL/6 mice in the light-dark exploration tests, and diazepam (an anxiolytics) treatment reduced the exploratory activity and central dopaminergic activities in Formosan wood mice, but not in C57BL/6 mice. After repeated exposure to light-dark exploration tests, the latency to dark zone was increased, and the duration in light zone as well as the central DAergic activity were decreased in C57BL/6 mice. This study provides comparative findings; Formosan wood mice showed the higher exploratory activities than C57BL/6 mice did, and their central DAergic activities were related to the behavioral responses in these two mice. This could potentially shed light on the reasons behind the prevalence of higher exploration and central dopaminergic activities. Using Formosan wood mice as a model to study human diseases related to hyperactivity adds significant value to the potential research.
Asunto(s)
Conducta Animal , Dopamina , Conducta Exploratoria , Ratones Endogámicos C57BL , Murinae , Animales , Masculino , Ratones , Dopamina/metabolismo , Conducta Exploratoria/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Ácido 3,4-Dihidroxifenilacético/metabolismo , Diazepam/farmacología , Ansiolíticos/farmacología , Núcleo Accumbens/metabolismo , Núcleo Accumbens/efectos de los fármacos , Corteza Prefrontal/metabolismo , Corteza Prefrontal/efectos de los fármacos , Cuerpo Estriado/metabolismo , Cuerpo Estriado/efectos de los fármacos , Actividad Motora/efectos de los fármacosRESUMEN
Chronic environmental exposure to toxic heavy metals, which often occurs as a mixture through occupational and industrial sources, has been implicated in various neurological disorders, including Parkinsonism. Vanadium pentoxide (V2O5) typically presents along with manganese (Mn), especially in welding rods and high-capacity batteries, including electric vehicle batteries; however, the neurotoxic effects of vanadium (V) and Mn co-exposure are largely unknown. In this study, we investigated the neurotoxic impact of MnCl2, V2O5, and MnCl2-V2O5 co-exposure in an animal model. C57BL/6 mice were intranasally administered either de-ionized water (vehicle), MnCl2 (252 µg) alone, V2O5 (182 µg) alone, or a mixture of MnCl2 (252 µg) and V2O5 (182 µg) three times a week for up to one month. Following exposure, we performed behavioral, neurochemical, and histological studies. Our results revealed dramatic decreases in olfactory bulb (OB) weight and levels of tyrosine hydroxylase, dopamine, and 3,4-dihydroxyphenylacetic acid in the treatment groups compared to the control group, with the Mn/V co-treatment group producing the most significant changes. Interestingly, increased levels of α-synuclein expression were observed in the substantia nigra (SN) of treated animals. Additionally, treatment groups exhibited locomotor deficits and olfactory dysfunction, with the co-treatment group producing the most severe deficits. The treatment groups exhibited increased levels of the oxidative stress marker 4-hydroxynonenal in the striatum and SN, as well as the upregulation of the pro-apoptotic protein PKCδ and accumulation of glomerular astroglia in the OB. The co-exposure of animals to Mn/V resulted in higher levels of these metals compared to other treatment groups. Taken together, our results suggest that co-exposure to Mn/V can adversely affect the olfactory and nigral systems. These results highlight the possible role of environmental metal mixtures in the etiology of Parkinsonism.
Asunto(s)
Compuestos de Manganeso , Manganeso , Ratones Endogámicos C57BL , Vanadio , Animales , Ratones , Manganeso/toxicidad , Vanadio/toxicidad , Masculino , Bulbo Olfatorio/metabolismo , Bulbo Olfatorio/efectos de los fármacos , Bulbo Olfatorio/patología , Dopamina/metabolismo , Compuestos de Vanadio , Estrés Oxidativo/efectos de los fármacos , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/inducido químicamente , alfa-Sinucleína/metabolismo , Cloruros/toxicidad , Cloruros/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Aldehídos/metabolismo , Sustancia Negra/metabolismo , Sustancia Negra/efectos de los fármacos , Sustancia Negra/patología , Modelos Animales de Enfermedad , Ácido 3,4-Dihidroxifenilacético/metabolismoRESUMEN
A series of novel Schiff base derivatives (1-28) of 3,4-dihydroxyphenylacetic acid were synthesized in a multi-step reaction. All the synthesized Schiff bases were obtained in high yields and their structures were determined by 1HNMR, 13CNMR, and HR-ESI-MS spectroscopy. Except for compounds 22, 26, 27, and 28, all derivatives show excellent to moderate α-glucosidase inhibition. Compounds 5 (IC50 = 12.84 ± 0.52 µM), 4 (IC50 = 13.64 ± 0.58 µM), 12 (IC50 = 15.73 ± 0.71 µM), 13 (IC50 = 16.62 ± 0.47 µM), 15 (IC50 = 17.40 ± 0.74 µM), 3 (IC50 = 18.45 ± 1.21 µM), 7 (IC50 = 19.68 ± 0.82 µM), and 2 (IC50 = 20.35 ± 1.27 µM) shows outstanding inhibition as compared to standard acarbose (IC50 = 873.34 ± 1.67 µM). Furthermore, a docking study was performed to find out the interaction between the enzyme and the most active compounds. With this research work, 3,4-dihydroxyphenylacetic acid Schiff base derivatives have been introduced as a potential class of α-glucosidase inhibitors that have remained elusive till now.
Asunto(s)
Ácido 3,4-Dihidroxifenilacético , Diseño de Fármacos , Inhibidores de Glicósido Hidrolasas , Simulación del Acoplamiento Molecular , Bases de Schiff , alfa-Glucosidasas , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/síntesis química , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/química , Ácido 3,4-Dihidroxifenilacético/análogos & derivados , Ácido 3,4-Dihidroxifenilacético/química , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ácido 3,4-Dihidroxifenilacético/farmacología , Bases de Schiff/química , Bases de Schiff/farmacología , Hidrazonas/química , Hidrazonas/farmacología , Hidrazonas/síntesis química , Relación Estructura-ActividadRESUMEN
While there is extensive research on alcohol dependence, the factors that make an individual vulnerable to developing alcoholism haven't been explored much. In this study, we aim to investigate how neonatal exposure to sex hormones affects alcohol intake and the regulation of the mesolimbic pathway in adulthood. The study aimed to investigate the impact of neonatal exposure to a single dose of testosterone propionate (TP) or estradiol valerate (EV) on ethanol consumption in adult rats. The rats were subjected to a two-bottle free-choice paradigm, and the content of dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in the nucleus accumbens (NAcc) was measured using HPLC-ED. The expression of critical DA-related proteins in the mesolimbic pathway was evaluated through RT-qPCR and western blot analysis. Supraphysiological neonatal exposure to EV or TP resulted in increased ethanol intake over four weeks in adulthood. In addition, the DA and DOPAC content was reduced and increased in the NAcc of EV and TP-treated rats, and ß-endorphin content in the hypothalamus decreased in EV-treated rats. The VTA µ receptor and DA type 2 form short receptor (D2S) expression were significantly reduced in EV and TP male rats. Finally, in an extended 6-week protocol, the increase in ethanol consumption induced by EV was mitigated during the initial two hours post-naloxone injection. Neonatal exposure to sex hormones is a detrimental stimulus for the brain, which can facilitate the development of addictive behaviors, including alcohol use disorder.
Asunto(s)
Ácido 3,4-Dihidroxifenilacético , Consumo de Bebidas Alcohólicas , Animales Recién Nacidos , Dopamina , Estradiol , Núcleo Accumbens , Propionato de Testosterona , Animales , Masculino , Consumo de Bebidas Alcohólicas/metabolismo , Ratas , Núcleo Accumbens/metabolismo , Núcleo Accumbens/efectos de los fármacos , Estradiol/farmacología , Propionato de Testosterona/farmacología , Propionato de Testosterona/administración & dosificación , Dopamina/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Femenino , Etanol/farmacología , Etanol/administración & dosificación , Hormonas Esteroides Gonadales/metabolismo , Ratas Sprague-DawleyRESUMEN
In order to study the neuroprotective mechanism of cinnamaldehyde on reserpine-induced Parkinson's disease(PD) rat models, 72 male Wistar rats were randomly divided into blank group, model group, Madopar group, and cinnamaldehyde high-, medium-, and low-dose groups. Except for the blank group, the other groups were intraperitoneally injected with reserpine of 0.1 mg·kg~(-1) once every other morning, and cinnamaldehyde and Madopar solutions were gavaged every afternoon. Open field test, rotarod test, and oral chewing movement evaluation were carried out in the experiment. The brain was taken and fixed. The positive expression of dopamine receptor D1(DRD1) was detected by TSA, and the changes in neurotransmitters such as dopamine(DA) and 3,4-dihydroxyphenylacetic acid(DOPAC) in the brain were detected by enzyme-linked immunosorbent assay(ELISA). The protein and mRNA expression levels of tyrosine hydroxylase(TH) and α-synuclein(α-Syn) in substantia nigra(SN) were detected by RT-PCR and Western blot. The results showed that after the injection of reserpine, the hair color of the model group became yellow and dirty; the arrest behavior was weakened, and the body weight was reduced. The spontaneous movement and exploration behavior were reduced, and the coordination exercise ability was decreased. The number of oral chewing was increased, but the cognitive ability was decreased, and the proportion of DRD1 positive expression area in SN was decreased. The expression of TH protein and mRNA was down-regulated, and that of α-Syn protein and mRNA was up-regulated. After cinnamaldehyde intervention, it had an obvious curative effect on PD model animals. The spontaneous movement behavior, the time of staying in the rod, the time of movement, the distance of movement, and the number of standing times increased, and the number of oral chewing decreased. The proportion of DRD1 positive expression area in SN increased, and the protein and mRNA expression levels of α-Syn were down-regulated. The protein and mRNA expression levels of TH were up-regulated. In addition, the levels of DA, DOPAC, and homovanillic acid(HVA) neurotransmitters in the brain were up-regulated. This study can provide a new experimental basis for clinical treatment and prevention of PD.
Asunto(s)
Acroleína/análogos & derivados , Enfermedad de Parkinson , Ratas , Masculino , Animales , Enfermedad de Parkinson/etiología , Enfermedad de Parkinson/genética , Reserpina/efectos adversos , Reserpina/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ratas Wistar , Sustancia Negra/metabolismo , ARN Mensajero/metabolismo , Neurotransmisores/metabolismo , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has a direct impact on the dopaminergic neurons in the substantia nigra pars compacta (SNpc), dopamine in the striatum (ST), homovanillic acid (HVA), neurotrophic factors of the SNpc, and ST regions leading to Parkinson's disease (PD). Dopaminergic neuron atrophy in the SNpc and dopamine degradation in the ST have an explicit link to disrupted homeostasis of the neurotrophic factor brain-derived neurotrophic factor (BDNF) of the SNpc and ST regions. Chrysin is a flavonoid with a pharmacological potential that directly influences neurotrophic levels as well as neurotransmitters. As a result, analysis of the altering levels of neurotransmitters such as dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), are observed via high-performance liquid chromatography (HPLC) and the confirmation of the influential role of BDNF and glial-derived neurotrophic factor (GDNF) in the homeostasis of dopamine, DOPAC, and HAV via examination of gene expression. The observation confirmed that chrysin balances the altering levels of neurotransmitters as well as neurotrophic factors. The protocols for reverse transcription-polymerase chain reaction (RT-PCR) and HPLC analysis for neurotransmitter levels from the SNpc and ST regions of acute PD mice brain-induced MPTP are described in this chapter.
Asunto(s)
Enfermedad de Parkinson , Ratones , Animales , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Dopamina/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Ácido Homovanílico/metabolismo , Sustancia Negra/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Flavonoides/farmacología , Flavonoides/metabolismo , Cuerpo Estriado/metabolismo , Neurotransmisores/metabolismo , Ratones Endogámicos C57BL , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Despite the advent of combination anti-retroviral therapy (cART), nearly half of people infected with HIV treated with cART still exhibit HIV-associated neurocognitive disorders (HAND). HAND can be worsened by co-morbid opioid use disorder. The basal ganglia are particularly vulnerable to HIV-1 and exhibit higher viral loads and more severe pathology, which can be exacerbated by co-exposure to opioids. Evidence suggests that dopaminergic neurotransmission is disrupted by HIV exposure, however, little is known about whether co-exposure to opioids may alter neurotransmitter levels in the striatum and if this in turn influences behavior. Therefore, we assayed motor, anxiety-like, novelty-seeking, exploratory, and social behaviors, and levels of monoamines and their metabolites following 2 weeks and 2 months of Tat and/or morphine exposure in transgenic mice. Morphine decreased dopamine levels, but significantly elevated norepinephrine, the dopamine metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and the serotonin metabolite 5-hydroxyindoleacetic acid, which typically correlated with increased locomotor behavior. The combination of Tat and morphine altered dopamine, DOPAC, and HVA concentrations differently depending on the neurotransmitter/metabolite and duration of exposure but did not affect the numbers of tyrosine hydroxylase-positive neurons in the mesencephalon. Tat exposure increased the latency to interact with novel conspecifics, but not other novel objects, suggesting the viral protein inhibits exploratory behavior initiation in a context-dependent manner. By contrast, and consistent with prior findings that opioid misuse can increase novelty-seeking behavior, morphine exposure increased the time spent exploring a novel environment. Finally, Tat and morphine interacted to affect locomotor activity in a time-dependent manner, while grip strength and rotarod performance were unaffected. Together, our results provide novel insight into the unique effects of HIV-1 Tat and morphine on monoamine neurochemistry that may underlie their divergent effects on motor and exploratory behavior.
Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Ratones , Animales , Morfina/farmacología , Conducta Exploratoria , VIH-1/metabolismo , Dopamina/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ratones Transgénicos , Analgésicos Opioides/farmacología , Ácido Homovanílico , Neurotransmisores , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismoRESUMEN
This review highlights the advantages of high-precision liquid chromatography with an electrochemical detector (HPLC-ECD) in detecting and quantifying biological samples obtained through intracerebral microdialysis, specifically the serotonergic and dopaminergic systems: Serotonin (5-HT), 5-hydroxyindolacetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC), dopamine (DA), 3-metoxytryptamin (3-MT) and homovanillic acid (HVA). Recognized for its speed and selectivity, HPLC enables direct analysis of intracerebral microdialysis samples without complex derivatization. Various chromatographic methods, including reverse phase (RP), are explored for neurotransmitters (NTs) and metabolites separation. Electrochemical detector (ECD), particularly with glassy carbon (GC) electrodes, is emphasized for its simplicity and sensitivity, aimed at enhancing reproducibility through optimization strategies such as modified electrode materials. This paper underscores the determination of limits of detection (LOD) and quantification (LOQ) and the linear range (L.R.) showcasing the potential for real-time monitoring of compounds concentrations. A non-exhaustive compilation of literature values for LOD, LOQ, and L.R. from recent publications is included.
Asunto(s)
Dopamina , Serotonina , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Dopamina/metabolismo , Cromatografía Liquida , Serotonina/metabolismo , Neurotransmisores , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ácido Hidroxiindolacético/análisis , Ácido Hidroxiindolacético/metabolismo , Monoaminas BiogénicasRESUMEN
BACKGROUND & AIMS: Biochemical changes of neurotransmitters underlying major depressive disorder (MDD) are unknown. This study preliminarily explored the association between neurotransmitters with MDD and the possibility of objective laboratory prediction of neurotransmitter involvement in MDD. METHODS: A total of 87 first-diagnosed, drug-naïve patients with depression and 50 healthy controls (HCs) were included in the cross-sectional study. The levels and turnovers of neurotransmitters (glutamine (GLN), glutamic acid (GLU), γ-2Aminobutiric acid (GABA), kainate (KA), vanillylmandelic acid (VMA), 3-methoxy 4-hydroxyphenyl ethylene glycol (MHPG), noradrenaline (NE), homovanillic acid (HVA), dihydroxy-phenyl acetic acid (DOPAC), dopamine (DA), tryptophane (TRP), kynurenine (KYN), serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA)) were determined and the confounding factors were adjusted. Then a correlation and a predictive analysis towards neurotransmitters for MDD were performed. RESULTS: After adjusting confounding factors, GLU (OR = 1.159), (GLU+ GABA)/GLN (OR = 1.217), DOPAC (OR = 1.106), DOPAC/DA (OR = 1.089) and (DOPAC+ HVA)/DA (OR = 1.026) enacted as risk factors of MDD, while KYN (OR = 0.992) was a protective factor. GABAergic and TRPergic pathways were associated with severity of depressive and anxiety symptoms in patients with depression. The predictive model for MDD (AUC = 0.775, 95%CI 0.683-0.860) consisted of KYN (OR = 0.990) and (GLU + GABA)/GLN (OR = 4.101). CONCLUSIONS: First-diagnosed, drug-naïve depression patients showed abnormal neurotransmitter composition. GLU, (GLU + GABA)/GLN, DOPAC, DOPAC/DA and (DOPAC + HVA)/DA were risk factors of MDD, while KYN was a protective factor. GABAergic and TRPergic pathways were correlated with MDD clinical characteristics. KYN and (GLU + GABA)/GLN may have a predictive value for MDD.
Asunto(s)
Trastorno Depresivo Mayor , Fenilacetatos , Humanos , Depresión , Ácido 3,4-Dihidroxifenilacético/metabolismo , Estudios Transversales , Dopamina/metabolismo , Neurotransmisores , Ácido Homovanílico/metabolismo , Quinurenina , Ácido Glutámico , Glutamina , Serotonina/metabolismo , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Toxoplasma gondii is a single-celled parasite that causes a disease called toxoplasmosis. It can reach the central nervous system, but the mechanism of T. gondii disrupting the functioning of these brain regions occurs in bradyzoite stage of parasite, causing brain damage by forming tissue cysts in brain. In our study, the effects of T. gondii on locomotor activity, anxiety, learning and memory, and norepinephrine (NE), levodopa (L-DOPA), dopamine (DA) and 3,4-D-dihydroxyphenylacetic acid (DOPAC) catecholamines in amygdala, striatum, prefrontal cortex and hippocampus regions of the brain were investigated in bradyzoite stage. Twenty male Albino mice Mus musculus, 4-5 weeks old, weighing 20-25 g, were used. T. gondii inoculated to mice intraperitonealy with 48-50-hour passages of T. gondii RH Ankara strain. For intraperitoneal inoculation of mice 5x104 tachyzoites per mouse. No inoculation was made in control group (n: 20). Locomotor activity behavior in open field test (OFT), anxious behavior in elevated plus maze (EPM), and learning behavior in novel object recognition (NOR) tests were evaluated. NE, L-DOPA, DA and DOPAC were measured by HPLC in brain tissues of amygdala, striatum, prefrontal cortex and hippocampus. A decrease was observed in the locomotor activity, anxiety and learning values of the T. gondii group compared to the control group (p < 0.05). The heighten in NE and L-DOPA levels in amygdala tissue of T. gondii group compared to control group, an elevation in NE, L-DOPA, DA and DOPAC levels in striatum tissue, and an increase in levels of NE in prefrontal cortex tissue were detected in monoamine results. In hippocampus tissue, an increase was observed in DA levels, while a decrease was observed in NE, L-DOPA and DOPAC levels. In our study, it has been shown that T. gondii in bradyzoite stage reduces locomotor activity, causes learning and memory impairment, and has anxiogenic effects.
Asunto(s)
Toxoplasma , Toxoplasmosis , Ratones , Masculino , Animales , Levodopa , Ácido 3,4-Dihidroxifenilacético , Encéfalo , Dopamina , NorepinefrinaRESUMEN
The present study was performed to examine if catechol oxidation is higher in brains from patients with Parkinson's disease compared to age-matched controls, and if catechol oxidation increases with age. Brain tissue from Parkinson patients and age-matched controls was examined for oxidation of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and 3,4-dihydroxyphenylalanine (DOPA) to corresponding quinones, by measurement of 5-S-cysteinyl-dopamine, 5-S-cysteinyl-DOPAC and 5-S-cysteinyl-DOPA. The cysteinyl catechols are assumed to be biomarkers for DA, DOPAC and DOPA autoxidation and part of the biosynthetic pathway of neuromelanin. The concentrations of the 5-S-cysteinyl catechols were lower, whereas the 5-S-cysteinyl-DA/DA and 5-S-cysteinyl-DOPAC/DOPAC ratios tended to be higher in the Parkinson group compared to controls, which was interpreted as a higher degree of oxidation. High 5-S-cysteinyl-DA/DA ratios were found in the substantia nigra of a sub-population of the Parkinson group. Based on 5-S-cysteinyl-DA/DA ratios, dopamine oxidation was found to increase statistically significantly with age in the caudate nucleus, and non-significantly in the substantia nigra. In conclusion, the occurrence of 5-S-cysteinyl-DA, 5-S-cysteinyl-DOPAC and 5-S-cysteinyl-DOPA was demonstrated in dopaminergic brain areas of humans, a tendency for higher oxidation of DA in the Parkinson group compared to controls was observed as well as a statistically significant increase in DA oxidation with age. Possibly, autoxidation of DA and other catechols are involved in both normal and pathological ageing of the brain. This study confirms one earlier but small study, as well as complements one study on non-PD cases and one study on both PD cases and controls on NM bound or integrated markers or catechols.
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Cisteinildopa/análogos & derivados , Dopamina , Enfermedad de Parkinson , Humanos , Dopamina/metabolismo , Enfermedad de Parkinson/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Dihidroxifenilalanina , Encéfalo/metabolismo , Catecoles/metabolismo , EnvejecimientoRESUMEN
BACKGROUND: Despite significant progress in understanding the mechanisms underlying hippocampal involvement in neuropsychiatric systemic lupus erythematosus (NPSLE), our understanding of how neuroinflammation affects the brain neurotransmitter systems is limited. To date, few studies have investigated the role of neurotransmitters in pathogenesis of NPSLE with contradictory results. METHODS: Hippocampal tissue from NZB/W-F1 lupus-prone mice and age-matched control strains were dissected in both pre-nephritic (3-month-old) and nephritic (6-month-old) stages. High-Performance Liquid Chromatography (HPLC) was used to evaluate the level of serotonin (5-HT), dopamine (DA), and their metabolites 5-HIAA and DOPAC, respectively, in mouse hippocampi. RESULTS: Lupus mice exhibit decreased levels of serotonin at the early stages of the disease, along with intact levels of its metabolite 5-HIAA. The 5-HT turnover ratio (5-HIAA/5-HT ratio) was increased in the hippocampus of lupus mice at pre-nephritic stage suggesting that low hippocampal serotonin levels in lupus are attributed to decreased serotonin synthesis. Both DA and DOPAC levels remained unaffected in lupus hippocampus at both early and late stages. CONCLUSION: Impaired hippocampal serotonin synthesis in the hippocampus of lupus-prone mice represents an early neuropsychiatric event. These findings may have important implications for the use of symptomatic therapy in diffuse NPSLE.
Asunto(s)
Lupus Eritematoso Sistémico , Vasculitis por Lupus del Sistema Nervioso Central , Ratones , Animales , Serotonina/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Ácido Hidroxiindolacético/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Dopamina/metabolismo , Hipocampo , Vasculitis por Lupus del Sistema Nervioso Central/metabolismoRESUMEN
Carbon-fiber microelectrodes (CFMEs) are primarily used to detect neurotransmitters in vivo with fast-scan cyclic voltammetry (FSCV) but other carbon nanomaterial electrodes are being developed. CFME sensitivity to dopamine is improved by applying a constant 1.5 V vs. Ag/AgCl for 3 minutes while dipped in 1 M KOH, which etches the surface and adds oxygen functional groups. However, KOH etching of other carbon nanomaterials and applications to other neurochemicals have not been investigated. Here, we explored KOH etching of CFMEs and carbon nanotube yarn microelectrodes (CNTYMEs) to characterize sensitivity to dopamine, epinephrine, norepinephrine, serotonin, and 3,4-dihydroxyphenylacetic acid (DOPAC). With CNTYMEs, the potential was applied in KOH for 1 minute because the electrode surface cracked with the longer time. KOH treatment increased electrode sensitivity to each cationic neurotransmitter roughly 2-fold for CFMEs, and 2- to 4-fold for CNTYMEs. KOH treatment decreased the background current of the CFMEs by etching the surface carbon; however, KOH-treatment increased the CNTYME background current because the potential separates individual nanotubes. For DOPAC, the current increase was smaller at CNTYMEs because it is anionic and was repelled by the negative holding potential and did not access the crevices. XPS and Raman spectroscopy showed that KOH treatment changed the CNTYME surface chemistry by increasing defect sites and adding oxide functional groups. KOH-treated CNTYMEs had less fouling to serotonin than normal CNTYMEs. Therefore, KOH treatment activates both CFMEs and CNTYMEs and could be used in biological measurements to increase the sensitivity and decrease fouling for neurochemical measurements.
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Nanoestructuras , Nanotubos de Carbono , Dopamina , Serotonina , Ácido 3,4-Dihidroxifenilacético , Microelectrodos , Nanotubos de Carbono/química , Neurotransmisores , Fibra de CarbonoRESUMEN
CHIR99021, also known as laduviglusib or CT99021, is a Glycogen-synthase kinase 3ß (GSK3ß) inhibitor, which has been reported as a promising drug for cardiomyocyte regeneration or treatment of sensorial hearing loss. Since the activation of dopamine (DA) receptors regulates dopamine synthesis and they can signal through the ß-arrestin pathway and GSK3ß, we decided to check the effect of GSK3ß inhibitors (CHIR99021, SB216763 and lithium ion) on the control of DA synthesis. Using ex vivo experiments with minces from rat brain striatum, we observed that CHIR99021, but not SB216763 or lithium, causes complete abrogation of both DA synthesis and accumulation, pointing to off-target effects of CHIR99021. This decrease can be attributed to tyrosine hydroxylase (TH) inhibition since the accumulation of l-DOPA in the presence of a DOPA decarboxylase inhibitor was similarly decreased. On the other hand, CHIR99021 caused a dramatic increase in the DOPAC/DA ratio, an indicator of DA metabolization, and hindered DA incorporation into striatum tissue. Tetrabenazine, an inhibitor of DA vesicular transport, also caused DA depletion and DOPAC/DA ratio increase to the same extent as CHIR99021. In addition, both CHIR99021 or SB216763, but not lithium, decreased TH phosphorylation in Ser19, but not in Ser31 or Ser40. These results demonstrate that CHIR99021 can lead to TH inactivation and DA depletion in brain striatum, opening the possibility of its use in DA-related disorders, and shows effects to be considered in future clinical trials. More work is needed to find the mechanism exerted by CHIR99021 on DA accumulation.
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Cuerpo Estriado , Dopamina , Tirosina 3-Monooxigenasa , Animales , Ratas , Ácido 3,4-Dihidroxifenilacético/metabolismo , Cuerpo Estriado/enzimología , Dopamina/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Litio/farmacología , Tirosina 3-Monooxigenasa/antagonistas & inhibidoresRESUMEN
We report a 49-year-old patient suffering from spastic paraplegia with a novel heterozygous mutation and analyzed the levels of heat shock proteins (hsp)-27, dopamine (DA), and its metabolites in their cerebrospinal fluid (CSF). The hsp27 protein concentration in the patient's CSF was assayed by an ELISA kit, while DA levels and its metabolites in the CSF, 3,4-dihydroxyphenylacetic acid (DOPAC), Cys-DA, and Cys-DOPA were measured by HPLC. Whole exome sequencing demonstrated SPG-11 c.1951C>T and novel SYNJ1 c.2614G>T mutations, both heterozygous recessive. The patient's DA and DOPAC levels in their CSF were significantly decreased (53.0 ± 6.92 and 473.3 ± 72.19, p < 0.05, respectively) while no differences were found in their Cys-DA. Nonetheless, Cys-DA/DOPAC ratio (0.213 ± 0.024, p < 0.05) and hsp27 levels (1073.0 ± 136.4, p < 0.05) were significantly higher. To the best of our knowledge, the c.2614G>T SYNJ1 mutation has not been previously reported. Our patient does not produce fully functional spatacsin and synaptojanin-1 proteins. In this line, our results showed decreased DA and DOPAC levels in the patient's CSF, indicating loss of DAergic neurons. Many factors have been described as being responsible for the increased cys-DA/DOPAC ratio, such as MAO inhibition and decreased antioxidant activity in DAergic neurons which would increase catecholquinones and consequently cysteinyl-catechols. In conclusion, haploinsufficiency of spatacsin and synaptojanin-1 proteins might be the underlying cause of neurodegeneration produced by protein trafficking defects, DA vesicle trafficking/recycling processes, autophagy dysfunction, and cell death leading to hsp27 upregulation as a cellular mechanism of protection and/or to balance impaired protein trafficking.
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Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico , Humanos , Persona de Mediana Edad , Ácido 3,4-Dihidroxifenilacético/líquido cefalorraquídeo , Dopamina , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico HSP27/genética , Mutación , Paraplejía , Regulación hacia ArribaRESUMEN
OBJECTIVE: Our goal is to investigate if microbiota composition modulates reward signaling and assess the role of the vagus in mediating microbiota to brain communication. METHODS: Male germ-free Fisher rats were colonized with gastrointestinal contents from chow (low fat (LF) ConvLF) or HF (ConvHF) fed rats. RESULTS: Following colonization, ConvHF rats consumed significantly more food than ConvLF animals. ConvHF rats displayed lower feeding-induced extracellular DOPAC levels (a metabolite of dopamine) in the Nucleus Accumbens (NAc) as well as reduced motivation for HF foods compared to ConvLF rats. Dopamine receptor 2 (DDR2) expression levels in the NAc were also significantly lower in ConvHF animals. Similar deficits were observed in conventionally raised HF fed rats, showing that diet-driven alteration in reward can be initiated via microbiota. Selective gut to brain deafferentation restored DOPAC levels, DRD2 expression, and motivational drive in ConvHF rats. CONCLUSIONS: We concluded from these data that a HF-type microbiota is sufficient to alter appetitive feeding behavior and that bacteria to reward communication is mediated by the vagus nerve.
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Eje Cerebro-Intestino , Conducta Alimentaria , Ratas , Masculino , Animales , Ácido 3,4-Dihidroxifenilacético , Conducta Alimentaria/fisiología , Recompensa , BacteriasRESUMEN
BACKGROUND: Glucagon-like peptide1 receptor (GLP-1R) agonists have been found to reduce alcohol drinking in rodents and overweight patients with alcohol use disorder (AUD). However, the probability of low semaglutide doses, an agonist with higher potency and affinity for GLP-1R, to attenuate alcohol-related responses in rodents and the underlying neuronal mechanisms is unknown. METHODS: In the intermittent access model, we examined the ability of semaglutide to decrease alcohol intake and block relapse-like drinking, as well as imaging the binding of fluorescently marked semaglutide to nucleus accumbens (NAc) in both male and female rats. The suppressive effect of semaglutide on alcohol-induced locomotor stimulation and in vivo dopamine release in NAc was tested in male mice. We evaluated effect of semaglutide on the in vivo release of dopamine metabolites (DOPAC and HVA) and gene expression of enzymes metabolising dopamine (MAOA and COMT) in male mice. FINDINGS: In male and female rats, acute and repeated semaglutide administration reduced alcohol intake and prevented relapse-like drinking. Moreover, fluorescently labelled semaglutide was detected in NAc of alcohol-drinking male and female rats. Further, semaglutide attenuated the ability of alcohol to cause hyperlocomotion and to elevate dopamine in NAc in male mice. As further shown in male mice, semaglutide enhanced DOPAC and HVA in NAc when alcohol was onboard and increased the gene expression of COMT and MAOA. INTERPRETATION: Altogether, this indicates that semaglutide reduces alcohol drinking behaviours, possibly via a reduction in alcohol-induced reward and NAc dependent mechanisms. As semaglutide also decreased body weight of alcohol-drinking rats of both sexes, upcoming clinical studies should test the plausibility that semaglutide reduces alcohol intake and body weight in overweight AUD patients. FUNDING: Swedish Research Council (2019-01676), LUA/ALF (723941) from the Sahlgrenska University Hospital and the Swedish brain foundation.
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Alcoholismo , Dopamina , Femenino , Ratas , Ratones , Masculino , Animales , Exenatida/farmacología , Dopamina/metabolismo , Ácido 3,4-Dihidroxifenilacético , Sobrepeso , Etanol/efectos adversos , Etanol/metabolismo , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/tratamiento farmacológico , RecurrenciaRESUMEN
Tetrodotoxin (TTX) inhibits neurotransmission in animals, and there is no specific antidote. In clinical practice in China, Althaea rosea (A. rosea flower) extract has been used to treat TTX poisoning. In this work, the efficacy of the ethyl acetate fraction extract of A. rosea flower in treating TTX poisoning in rats was investigated. A high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to determine nine neurotransmitters in rat brain tissue, including γ-aminobutyric acid (GABA), dopamine (DA), 5-hydroxytryptamine (5-HT), noradrenaline (NE), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindole-3-acetic acid (5-HIAA), epinephrine (E), and tyramine (Tyn). The detoxifying effect of A. rosea flower was verified by comparing the changes in neurotransmitters' content in brain tissue before and after poisoning in rats. The assay was performed in multiple reaction monitoring mode. The quantification method was performed by plotting an internal-standard working curve with good linearity (R2 > 0.9941) and sensitivity. Analyte recoveries were 94.04-107.53% (RSD < 4.21%). Results indicated that the levels of 5-HT, DA, E, and NE in the brains of TTX-intoxicated rats decreased, whereas the levels of GABA, Tyn, and 5-HIAA showed an opposite trend, and HVA and DOPAC were not detected. The levels of all seven neurotransmitters returned to normal after the gavage administration of ethyl acetate extract of A. rosea flower to prove that the ethyl acetate extract of A. rosea flower had a therapeutic effect on TTX poisoning. The work provided new ideas for studies on TTX detoxification.