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1.
J Pineal Res ; 76(3): e12955, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606787

RESUMO

Identifying the target cells of a hormone is a key step in understanding its function. Once the molecular nature of the receptors for a hormone has been established, researchers can use several techniques to detect these receptors. Here I will review the different tools used over the years to localize melatonin receptors and the problems associated with each of these techniques. The radioligand 2-[125I] iodomelatonin was the first tool to allow localization of melatonin receptors on tissue sections. Once the MT1 and MT2 receptors were cloned, in situ hybridization could be used to detect the messenger RNA for these receptors. The deduced amino acid sequences for MT1 and MT2 receptors allowed the production of peptide immunogens to generate antibodies against the MT1 and MT2 receptors. Finally, transgenic reporters driven by the promoter elements of the MT1 and MT2 genes have been used to map the expression of MT1 and MT2 in the brain and the retina. Several issues have complicated the localization of melatonin receptors and the characterization of melatonin target cells over the last three decades. Melatonin receptors are expressed at low levels, leading to sensitivity issues for their detection. The second problem are specificity issues with antibodies directed against the MT1 and MT2 melatonin receptors. These receptors are G protein-coupled receptors and many antibodies directed against such receptors have been shown to present similar problems concerning their specificity. Despite these specificity problems which start to be seriously addressed by recent studies, antibodies will be important tools in the future to identify and phenotype melatonin target cells. However, we will have to be more stringent than previously when establishing their specificity. The results obtained by these antibodies will have to be confronted and be coherent with results obtained by other techniques.


Assuntos
Melatonina , Receptor MT2 de Melatonina , Receptores de Melatonina/metabolismo , Receptor MT2 de Melatonina/genética , Receptor MT2 de Melatonina/metabolismo , Melatonina/metabolismo , Receptor MT1 de Melatonina/genética , Receptor MT1 de Melatonina/metabolismo , Encéfalo/metabolismo , Sequência de Aminoácidos
2.
Cells ; 13(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38607030

RESUMO

Cockayne syndrome (CS) is a rare hereditary autosomal recessive disorder primarily caused by mutations in Cockayne syndrome protein A (CSA) or B (CSB). While many of the functions of CSB have been at least partially elucidated, little is known about the actual developmental dysregulation in this devasting disorder. Of particular interest is the regulation of cerebral development as the most debilitating symptoms are of neurological nature. We generated neurospheres and cerebral organoids utilizing Cockayne syndrome B protein (CSB)-deficient induced pluripotent stem cells derived from two patients with distinct severity levels of CS and healthy controls. The transcriptome of both developmental timepoints was explored using RNA-Seq and bioinformatic analysis to identify dysregulated biological processes common to both patients with CS in comparison to the control. CSB-deficient neurospheres displayed upregulation of the VEGFA-VEGFR2 signalling pathway, vesicle-mediated transport and head development. CSB-deficient cerebral organoids exhibited downregulation of brain development, neuron projection development and synaptic signalling. We further identified the upregulation of steroid biosynthesis as common to both timepoints, in particular the upregulation of the cholesterol biosynthesis branch. Our results provide insights into the neurodevelopmental dysregulation in patients with CS and strengthen the theory that CS is not only a neurodegenerative but also a neurodevelopmental disorder.


Assuntos
Síndrome de Cockayne , Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , DNA Helicases/genética , Enzimas Reparadoras do DNA/metabolismo , Síndrome de Cockayne/genética , Síndrome de Cockayne/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Encéfalo/metabolismo , Organoides/metabolismo
3.
ACS Nano ; 18(15): 10596-10608, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38557034

RESUMO

Continuously monitoring neurotransmitter dynamics can offer profound insights into neural mechanisms and the etiology of neurological diseases. Here, we present a miniaturized implantable fluorescence probe integrated with metal-organic frameworks (MOFs) for deep brain dopamine sensing. The probe is assembled from physically thinned light-emitting diodes (LEDs) and phototransistors, along with functional surface coatings, resulting in a total thickness of 120 µm. A fluorescent MOF that specifically binds dopamine is introduced, enabling a highly sensitive dopamine measurement with a detection limit of 79.9 nM. A compact wireless circuit weighing only 0.85 g is also developed and interfaced with the probe, which was later applied to continuously monitor real-time dopamine levels during deep brain stimulation in rats, providing critical information on neurotransmitter dynamics. Cytotoxicity tests and immunofluorescence analysis further suggest a favorable biocompatibility of the probe for implantable applications. This work presents fundamental principles and techniques for integrating fluorescent MOFs and flexible electronics for brain-computer interfaces and may provide more customized platforms for applications in neuroscience, disease tracing, and smart diagnostics.


Assuntos
Dopamina , Estruturas Metalorgânicas , Ratos , Animais , Dopamina/análise , Estruturas Metalorgânicas/metabolismo , Corantes Fluorescentes/metabolismo , Fluorescência , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Neurotransmissores/metabolismo
4.
Front Immunol ; 15: 1384270, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576620

RESUMO

With the proposal of the "biological-psychological-social" model, clinical decision-makers and researchers have paid more attention to the bidirectional interactive effects between psychological factors and diseases. The brain-gut-microbiota axis, as an important pathway for communication between the brain and the gut, plays an important role in the occurrence and development of inflammatory bowel disease. This article reviews the mechanism by which psychological disorders mediate inflammatory bowel disease by affecting the brain-gut-microbiota axis. Research progress on inflammatory bowel disease causing "comorbidities of mind and body" through the microbiota-gut-brain axis is also described. In addition, to meet the needs of individualized treatment, this article describes some nontraditional and easily overlooked treatment strategies that have led to new ideas for "psychosomatic treatment".


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Transtornos Mentais , Microbiota , Humanos , Encéfalo/metabolismo , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/metabolismo , Transtornos Mentais/metabolismo
5.
Front Immunol ; 15: 1375453, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596671

RESUMO

The overconsumption of dietary fructose has been proposed as a major culprit for the rise of many metabolic diseases in recent years, yet the relationship between a high fructose diet and neurological dysfunction remains to be explored. Although fructose metabolism mainly takes place in the liver and intestine, recent studies have shown that a hyperglycemic condition could induce fructose metabolism in the brain. Notably, microglia, which are tissue-resident macrophages (Mφs) that confer innate immunity in the brain, also express fructose transporters (GLUT5) and are capable of utilizing fructose as a carbon fuel. Together, these studies suggest the possibility that a high fructose diet can regulate the activation and inflammatory response of microglia by metabolic reprogramming, thereby altering the susceptibility of developing neurological dysfunction. In this review, the recent advances in the understanding of microglia metabolism and how it supports its functions will be summarized. The results from both in vivo and in vitro studies that have investigated the mechanistic link between fructose-induced metabolic reprogramming of microglia and its function will then be reviewed. Finally, areas of controversies and their associated implications, as well as directions that warrant future research will be highlighted.


Assuntos
Frutose , Microglia , Frutose/metabolismo , Microglia/metabolismo , Metabolismo dos Carboidratos , Fígado/metabolismo , Encéfalo/metabolismo
6.
ACS Chem Neurosci ; 15(8): 1684-1701, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564598

RESUMO

Copper oxide nanoparticles (CuO-NPs) are commonly used metal oxides. Betaine possesses antioxidant and neuroprotective activities. The current study aimed to investigate the neurotoxic effect of CuO-NPs on rats and the capability of betaine to mitigate neurotoxicity. Forty rats; 4 groups: group I a control, group II intraperitoneally CuO-NPs (0.5 mg/kg/day), group III orally betaine (250 mg/kg/day) and CuO-NPs, group IV orally betaine for 28 days. Rats were subjected to neurobehavioral assessments. Brain samples were processed for biochemical, molecular, histopathological, and immunohistochemical analyses. Behavioral performance of betaine demonstrated increasing locomotion and cognitive abilities. Group II exhibited significantly elevated malondialdehyde (MDA), overexpression of interleukin-1 beta (IL-1ß), and tumor necrosis factor-alpha (TNF-α). Significant decrease in glutathione (GSH), and downregulation of acetylcholine esterase (AChE), nuclear factor erythroid 2-like protein 2 (Nrf-2), and superoxide dismutase (SOD). Histopathological alterations; neuronal degeneration, pericellular spaces, and neuropillar vacuolation. Immunohistochemically, an intense immunoreactivity is observed against IL-1ß and glial fibrillary acidic protein (GFAP). Betaine partially neuroprotected against CuO-NPs associated alterations. A significant decrease at MDA, downregulation of IL-1ß, and TNF-α, a significant increase at GSH, and upregulation of AChE, Nrf-2, and SOD. Histopathological alterations partially ameliorated. Immunohistochemical intensity of IL-1ß and GFAP reduced. It is concluded that betaine neuroprotected against most of CuO-NP neurotoxic effects through antioxidant and cell redox system stimulating efficacy.


Assuntos
Cobre , Nanopartículas , Ratos , Animais , Cobre/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Betaína/farmacologia , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo , Superóxido Dismutase/metabolismo , Glutationa/metabolismo , Encéfalo/metabolismo , Óxidos/metabolismo , Óxidos/farmacologia
7.
Science ; 384(6691): 53-59, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38574132

RESUMO

Genomic DNA that resides in the nuclei of mammalian neurons can be as old as the organism itself. The life span of nuclear RNAs, which are critical for proper chromatin architecture and transcription regulation, has not been determined in adult tissues. In this work, we identified and characterized nuclear RNAs that do not turn over for at least 2 years in a subset of postnatally born cells in the mouse brain. These long-lived RNAs were stably retained in nuclei in a neural cell type-specific manner and were required for the maintenance of heterochromatin. Thus, the life span of neural cells may depend on both the molecular longevity of DNA for the storage of genetic information and also the extreme stability of RNA for the functional organization of chromatin.


Assuntos
Encéfalo , Cromatina , RNA Nuclear , Animais , Camundongos , Encéfalo/metabolismo , Regulação da Expressão Gênica , Heterocromatina/genética , RNA Nuclear/genética
8.
Cell Stem Cell ; 31(4): 519-536.e8, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579683

RESUMO

Traumatic brain injury (TBI) strongly correlates with neurodegenerative disease. However, it remains unclear which neurodegenerative mechanisms are intrinsic to the brain and which strategies most potently mitigate these processes. We developed a high-intensity ultrasound platform to inflict mechanical injury to induced pluripotent stem cell (iPSC)-derived cortical organoids. Mechanically injured organoids elicit classic hallmarks of TBI, including neuronal death, tau phosphorylation, and TDP-43 nuclear egress. We found that deep-layer neurons were particularly vulnerable to injury and that TDP-43 proteinopathy promotes cell death. Injured organoids derived from C9ORF72 amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) patients displayed exacerbated TDP-43 dysfunction. Using genome-wide CRISPR interference screening, we identified a mechanosensory channel, KCNJ2, whose inhibition potently mitigated neurodegenerative processes in vitro and in vivo, including in C9ORF72 ALS/FTD organoids. Thus, targeting KCNJ2 may reduce acute neuronal death after brain injury, and we present a scalable, genetically flexible cerebral organoid model that may enable the identification of additional modifiers of mechanical stress.


Assuntos
Esclerose Amiotrófica Lateral , Lesões Encefálicas Traumáticas , Demência Frontotemporal , Doenças Neurodegenerativas , Canais de Potássio Corretores do Fluxo de Internalização , Humanos , Esclerose Amiotrófica Lateral/etiologia , Esclerose Amiotrófica Lateral/patologia , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/terapia , Proteína C9orf72/metabolismo , Proteínas de Ligação a DNA/metabolismo , Demência Frontotemporal/etiologia , Demência Frontotemporal/patologia , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/patologia , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo
9.
Sci Rep ; 14(1): 7774, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565877

RESUMO

Human microbiota mainly resides on the skin and in the gut. Human gut microbiota can produce a variety of short chain fatty acids (SCFAs) that affect many physiological functions and most importantly modulate brain functions through the bidirectional gut-brain axis. Similarly, skin microorganisms also have identical metabolites of SCFAs reported to be involved in maintaining skin homeostasis. However, it remains unclear whether these SCFAs produced by skin bacteria can affect brain cognitive functions. In this study, we hypothesize that the brain's functional activities are associated with the skin bacterial population and examine the influence of local skin-bacterial growth on event-related potentials (ERPs) during an oddball task using EEG. Additionally, five machine learning (ML) methods were employed to discern the relationship between skin microbiota and cognitive functions. Twenty healthy subjects underwent three rounds of tests under different conditions-alcohol, glycerol, and water. Statistical tests confirmed a significant increase in bacterial population under water and glycerol conditions when compared to the alcohol condition. The metabolites of bacteria can turn phenol red from red-orange to yellow, confirming an increase in acidity. P3 amplitudes were significantly enhanced in response to only oddball stimulus at four channels (Fz, FCz, and Cz) and were observed after the removal of bacteria when compared with that under the water and glycerol manipulations. By using machine learning methods, we demonstrated that EEG features could be separated with a good accuracy (> 88%) after experimental manipulations. Our results suggest a relationship between skin microbiota and brain functions. We hope our findings motivate further study into the underlying mechanism. Ultimately, an understanding of the relationship between skin microbiota and brain functions can contribute to the treatment and intervention of diseases that link with this pathway.


Assuntos
Glicerol , Microbiota , Humanos , Encéfalo/metabolismo , Ácidos Graxos Voláteis/metabolismo , Cognição , Eletroencefalografia , Água
10.
Artigo em Inglês | MEDLINE | ID: mdl-38558503

RESUMO

The blood-brain barrier presents a key limitation to the administration of therapeutic molecules for the treatment of brain disease. While drugs administered orally or intravenously must cross this barrier to reach brain targets, the unique anatomical structure of the olfactory system provides a route to deliver drugs directly to the brain. Entering the brain via receptor, carrier, and adsorption-mediated transcytosis in the nasal olfactory and trigeminal regions has the potential to increase drug delivery. In this review, we introduce the physiological and anatomical structures of the nasal cavity, and summarize the possible modes of transport and the relevant receptors and carriers in the nose-to-brain pathway. Additionally, we provide examples of nanotherapeutics developed for intranasal drug delivery to the brain. Further development of nanoparticles that can be applied to intranasal delivery systems promises to improve drug efficacy and reduce drug resistance and adverse effects by increasing molecular access to the brain. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease.


Assuntos
Encéfalo , Nanopartículas , Encéfalo/metabolismo , Barreira Hematoencefálica/metabolismo , Administração Intranasal , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Nanopartículas/química
11.
J Neurosci Res ; 102(4): e25327, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38588037

RESUMO

Despite evidence of the beneficial effects of cannabidiol (CBD) in animal models of cocaine use disorder (CUD), CBD neuronal mechanisms remain poorly understood. This study investigated the effects of CBD treatment on brain glucose metabolism, in a CUD animal model, using [18F]FDG positron emission tomography (PET). Male C57Bl/6 mice were injected with cocaine (20 mg/kg, i.p.) every other day for 9 days, followed by 8 days of CBD administration (30 mg/kg, i.p.). After 48 h, animals were challenged with cocaine. Control animals received saline/vehicle. [18F]FDG PET was performed at four time points: baseline, last day of sensitization, last day of withdrawal/CBD treatment, and challenge. Subsequently, the animals were euthanized and immunohistochemistry was performed on the hippocampus and amygdala to assess the CB1 receptors, neuronal nuclear protein, microglia (Iba1), and astrocytes (GFAP). Results showed that cocaine administration increased [18F]FDG uptake following sensitization. CBD treatment also increased [18F]FDG uptake in both saline and cocaine groups. However, animals that were sensitized and challenged with cocaine, and those receiving only an acute cocaine injection during the challenge phase, did not exhibit increased [18F]FDG uptake when treated with CBD. Furthermore, CBD induced modifications in the integrated density of NeuN, Iba, GFAP, and CB1R in the hippocampus and amygdala. This is the first study addressing the impact of CBD on brain glucose metabolism in a preclinical model of CUD using PET. Our findings suggest that CBD disrupts cocaine-induced changes in brain energy consumption and activity, which might be correlated with alterations in neuronal and glial function.


Assuntos
Canabidiol , Cocaína , Camundongos , Animais , Masculino , Canabidiol/farmacologia , Canabidiol/metabolismo , Glucose/metabolismo , Fluordesoxiglucose F18/metabolismo , Encéfalo/metabolismo , Cocaína/farmacologia , Camundongos Endogâmicos C57BL
12.
Exp Biol Med (Maywood) ; 249: 10117, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590360

RESUMO

The risk factors and causes of intracerebral hemorrhage (ICH) and the degree of functional recovery after ICH are distinct between young and elderly patients. The increasing incidence of ICH in young adults has become a concern; however, research on the molecules and pathways involved ICH in subjects of different ages is lacking. In this study, tandem mass tag (TMT)-based proteomics was utilized to examine the protein expression profiles of perihematomal tissue from young and aged mice 24 h after collagenase-induced ICH. Among the 5,129 quantified proteins, ICH induced 108 and 143 differentially expressed proteins (DEPs) in young and aged mice, respectively; specifically, there were 54 common DEPs, 54 unique DEPs in young mice and 89 unique DEPs in aged mice. In contrast, aging altered the expression of 58 proteins in the brain, resulting in 39 upregulated DEPs and 19 downregulated DEPs. Bioinformatics analysis indicated that ICH activated different proteins in complement pathways, coagulation cascades, the acute phase response, and the iron homeostasis signaling pathway in mice of both age groups. Protein-protein interaction (PPI) analysis and ingenuity pathway analysis (IPA) demonstrated that the unique DEPs in the young and aged mice were related to lipid metabolism and carbohydrate metabolism, respectively. Deeper paired-comparison analysis demonstrated that apolipoprotein M exhibited the most significant change in expression as a result of both aging and ICH. These results help illustrate age-related protein expression changes in the acute phase of ICH.


Assuntos
Hemorragia Cerebral , Proteômica , Idoso , Humanos , Camundongos , Animais , Proteômica/métodos , Hemorragia Cerebral/metabolismo , Encéfalo/metabolismo , Envelhecimento , Proteínas/metabolismo
13.
Acta Neurobiol Exp (Wars) ; 84(1): 89-97, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38587320

RESUMO

Opioid addiction is critically dependent on the activation of N­methyl­D­aspartate (NMDA) receptors, which are widely found in the mesocorticolimbic system. Meanwhile, opioid addiction may affect the expression level of NMDA receptor subunits. The existence of GluN3 subunits in the NMDA receptor's tetramer structure reduces the excitatory current of the receptor channel. We evaluated the changes in the mRNA expression pattern of the GluN3B subunit of the NMDA receptor in rat brains following acute and chronic exposure to morphine. Chronic, escalating intraperitoneal doses of morphine or saline were administered twice daily to male Wistar rats for six days. Two other groups were injected with a single acute dose of morphine or saline. The mRNA level of the GluN3B subunit of the NMDA receptor in the striatum, hippocampus, and nucleus accumbens (NAc) was measured by real­time PCR. mRNA expression of the GluN3B subunit was considerably augmented (3.15 fold) in the NAc of animals chronically treated with morphine compared to the control group. The difference between rats that were chronically administered morphine and control rats was not statistically significant for other evaluated brain areas. In rats acutely treated with morphine, no significant differences were found for GluN3B subunit expression in the examined brain regions compared to the control group. It was concluded that chronic exposure to morphine notably increased the GluN3B subunit of the NMDA receptor in NAc. The extent of the impact of this finding on opioid addiction and its features requires further evaluation in future studies.


Assuntos
Morfina , Transtornos Relacionados ao Uso de Opioides , Ratos , Masculino , Animais , Morfina/farmacologia , Receptores de N-Metil-D-Aspartato , Ratos Wistar , Encéfalo/metabolismo , Transtornos Relacionados ao Uso de Opioides/metabolismo , RNA Mensageiro/metabolismo
14.
Fluids Barriers CNS ; 21(1): 33, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589879

RESUMO

BACKGROUND: The blood-brain barrier (BBB) is pivotal for the maintenance of brain homeostasis and it strictly regulates the cerebral transport of a wide range of endogenous compounds and drugs. While fasting is increasingly recognized as a potential therapeutic intervention in neurology and psychiatry, its impact upon the BBB has not been studied. This study was designed to assess the global impact of fasting upon the repertoire of BBB transporters. METHODS: We used a combination of in vivo and in vitro experiments to assess the response of the brain endothelium in male rats that were fed ad libitum or fasted for one to three days. Brain endothelial cells were acutely purified and transcriptionaly profiled using RNA-Seq. Isolated brain microvessels were used to assess the protein expression of selected BBB transporters through western blot. The molecular mechanisms involved in the adaptation to fasting were investigated in primary cultured rat brain endothelial cells. MCT1 activity was probed by in situ brain perfusion. RESULTS: Fasting did not change the expression of the main drug efflux ATP-binding cassette transporters or P-glycoprotein activity at the BBB but modulated a restrictive set of solute carrier transporters. These included the ketone bodies transporter MCT1, which is pivotal for the brain adaptation to fasting. Our findings in vivo suggested that PPAR δ, a major lipid sensor, was selectively activated in brain endothelial cells in response to fasting. This was confirmed in vitro where pharmacological agonists and free fatty acids selectively activated PPAR δ, resulting in the upregulation of MCT1 expression. Moreover, dosing rats with a specific PPAR δ antagonist blocked the upregulation of MCT1 expression and activity induced by fasting. CONCLUSIONS: Altogether, our study shows that fasting affects a selected set of BBB transporters which does not include the main drug efflux transporters. Moreover, we describe a previously unknown selective adaptive response of the brain vasculature to fasting which involves PPAR δ and is responsible for the up-regulation of MCT1 expression and activity. Our study opens new perspectives for the metabolic manipulation of the BBB in the healthy or diseased brain.


Assuntos
Barreira Hematoencefálica , PPAR delta , Ratos , Masculino , Animais , Barreira Hematoencefálica/metabolismo , PPAR delta/metabolismo , Células Endoteliais/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Encéfalo/metabolismo , Jejum
15.
J Neurosci Res ; 102(4): e25329, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38597144

RESUMO

There is a need for new treatments to reduce brain injuries derived from neonatal hypoxia/ischemia. The only viable option used in the clinic today in infants born at term is therapeutic hypothermia, which has a limited efficacy. Treatments with exogenous RNase have shown great promise in a range of different adult animal models including stroke, ischemia/reperfusion injury, or experimental heart transplantation, often by conferring vascular protective and anti-inflammatory effects. However, any neuroprotective function of RNase treatment in the neonate remains unknown. Using a well-established model of neonatal hypoxic/ischemic brain injury, we evaluated the influence of RNase treatment on RNase activity, gray and white matter tissue loss, blood-brain barrier function, as well as levels and expression of inflammatory cytokines in the brain up to 6 h after the injury using multiplex immunoassay and RT-PCR. Intraperitoneal treatment with RNase increased RNase activity in both plasma and cerebropinal fluids. The RNase treatment resulted in a reduction of brain tissue loss but did not affect the blood-brain barrier function and had only a minor modulatory effect on the inflammatory response. It is concluded that RNase treatment may be promising as a neuroprotective regimen, whereas the mechanistic effects of this treatment appear to be different in the neonate compared to the adult and need further investigation.


Assuntos
Lesões Encefálicas , Hipóxia-Isquemia Encefálica , Fármacos Neuroprotetores , Animais , Recém-Nascido , Lactente , Humanos , Animais Recém-Nascidos , Ribonucleases/metabolismo , Ribonucleases/farmacologia , Lesões Encefálicas/tratamento farmacológico , Encéfalo/metabolismo , Isquemia/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Modelos Animais de Doenças
16.
Fluids Barriers CNS ; 21(1): 30, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566110

RESUMO

BACKGROUND: Reduced clearance of cerebrospinal fluid (CSF) has been suggested as a pathological feature of Alzheimer's disease (AD). With extensive documentation in non-human mammals and contradictory human neuroimaging data it remains unknown whether the nasal mucosa is a CSF drainage site in humans. Here, we used dynamic PET with [1-11C]-Butanol, a highly permeable radiotracer with no appreciable brain binding, to test the hypothesis that tracer drainage from the nasal pathway reflects CSF drainage from brain. As a test of the hypothesis, we examined whether brain and nasal fluid drainage times were correlated and affected by brain amyloid. METHODS: 24 cognitively normal subjects (≥ 65 years) were dynamically PET imaged for 60 min. using [1-11C]-Butanol. Imaging with either [11C]-PiB or [18F]-FBB identified 8 amyloid PET positive (Aß+) and 16 Aß- subjects. MRI-determined regions of interest (ROI) included: the carotid artery, the lateral orbitofrontal (LOF) brain, the cribriform plate, and an All-turbinate region comprised of the superior, middle, and inferior turbinates. The bilateral temporalis muscle and jugular veins served as control regions. Regional time-activity were used to model tracer influx, egress, and AUC. RESULTS: LOF and All-turbinate 60 min AUC were positively associated, thus suggesting a connection between the brain and the nose. Further, the Aß+ subgroup demonstrated impaired tracer kinetics, marked by reduced tracer influx and slower egress. CONCLUSION: The data show that tracer kinetics for brain and nasal turbinates are related to each other and both reflect the amyloid status of the brain. As such, these data add to evidence that the nasal pathway is a potential CSF drainage site in humans. These data warrant further investigation of brain and nasal contributions to protein clearance in neurodegenerative disease.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Animais , Humanos , Conchas Nasais/metabolismo , Conchas Nasais/patologia , Butanóis/metabolismo , Doenças Neurodegenerativas/metabolismo , Tiazóis/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Doença de Alzheimer/metabolismo , Envelhecimento , Encéfalo/metabolismo , 1-Butanol/metabolismo , Peptídeos beta-Amiloides/metabolismo , Mamíferos/metabolismo
19.
Cell Commun Signal ; 22(1): 216, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570868

RESUMO

BACKGROUND: Radiation-induced brain injury (RIBI) is a common and severe complication during radiotherapy for head and neck tumor. Repetitive transcranial magnetic stimulation (rTMS) is a novel and non-invasive method of brain stimulation, which has been applied in various neurological diseases. rTMS has been proved to be effective for treatment of RIBI, while its mechanisms have not been well understood. METHODS: RIBI mouse model was established by cranial irradiation, K252a was daily injected intraperitoneally to block BDNF pathway. Immunofluorescence staining, immunohistochemistry and western blotting were performed to examine the microglial pyroptosis and hippocampal neurogenesis. Behavioral tests were used to assess the cognitive function and emotionality of mice. Golgi staining was applied to observe the structure of dendritic spine in hippocampus. RESULTS: rTMS significantly promoted hippocampal neurogenesis and mitigated neuroinflammation, with ameliorating pyroptosis in microglia, as well as downregulation of the protein expression level of NLRP3 inflammasome and key pyroptosis factor Gasdermin D (GSDMD). BDNF signaling pathway might be involved in it. After blocking BDNF pathway by K252a, a specific BDNF pathway inhibitor, the neuroprotective effect of rTMS was markedly reversed. Evaluated by behavioral tests, the cognitive dysfunction and anxiety-like behavior were found aggravated with the comparison of mice in rTMS intervention group. Moreover, the level of hippocampal neurogenesis was found to be attenuated, the pyroptosis of microglia as well as the levels of GSDMD, NLRP3 inflammasome and IL-1ß were upregulated. CONCLUSION: Our study indicated that rTMS notably ameliorated RIBI-induced cognitive disorders, by mitigating pyroptosis in microglia and promoting hippocampal neurogenesis via mediating BDNF pathway.


Assuntos
Lesões Encefálicas , Disfunção Cognitiva , Camundongos , Animais , Estimulação Magnética Transcraniana/efeitos adversos , Estimulação Magnética Transcraniana/métodos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Microglia/metabolismo , Piroptose , Inflamassomos/metabolismo , Encéfalo/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Cognição , Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Neurogênese/efeitos da radiação
20.
CNS Neurosci Ther ; 30(4): e14678, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572788

RESUMO

INTRODUCTION: Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disorder characterized by the presence of glial cytoplasmic inclusions (GCIs) containing aggregated α-synuclein (α-Syn). Accurate diagnosis and monitoring of MSA present significant challenges, which can lead to potential misdiagnosis and inappropriate treatment. Biomarkers play a crucial role in improving the accuracy of MSA diagnosis, and phosphorylated α-synuclein (p-syn) has emerged as a promising biomarker for aiding in diagnosis and disease monitoring. METHODS: A literature search was conducted on PubMed, Scopus, and Google Scholar using specific keywords and MeSH terms without imposing a time limit. Inclusion criteria comprised various study designs including experimental studies, case-control studies, and cohort studies published only in English, while conference abstracts and unpublished sources were excluded. RESULTS: Increased levels of p-syn have been observed in various samples from MSA patients, such as red blood cells, cerebrospinal fluid, oral mucosal cells, skin, and colon biopsies, highlighting their diagnostic potential. The α-Syn RT-QuIC assay has shown sensitivity in diagnosing MSA and tracking its progression. Meta-analyses and multicenter investigations have confirmed the diagnostic value of p-syn in cerebrospinal fluid, demonstrating high specificity and sensitivity in distinguishing MSA from other neurodegenerative diseases. Moreover, combining p-syn with other biomarkers has further improved the diagnostic accuracy of MSA. CONCLUSION: The p-syn stands out as a promising biomarker for MSA. It is found in oligodendrocytes and shows a correlation with disease severity and progression. However, further research and validation studies are necessary to establish p-syn as a reliable biomarker for MSA. If proven, p-syn could significantly contribute to early diagnosis, disease monitoring, and assessing treatment response.


Assuntos
Atrofia de Múltiplos Sistemas , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Atrofia de Múltiplos Sistemas/diagnóstico , Encéfalo/metabolismo , Biomarcadores/líquido cefalorraquidiano , Estudos de Casos e Controles , Estudos Multicêntricos como Assunto
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