RESUMEN
Cyanobacteria produce neurotoxic non-protein amino acids (NPAAs) that accumulate in ecosystems and food webs. American lobsters (Homarus americanus H. Milne-Edwards) are one of the most valuable seafood industries in Canada with exports valued at > $2 billion. Two previous studies have assessed the occurrence of ß-N-methylamino-L-alanine (BMAA) in a small number of lobster tissues but a complete study has not previously been undertaken. We measured NPAAs in eyeballs, brain, legs, claws, tails, and eggs of 4 lobsters per year for the 2021 and 2022 harvests. Our study included 4 male and 4 female lobsters. We detected BMAA and its isomers, N-(2-aminoethyl)glycine (AEG), 2,4-diaminobutyric acid (DAB) and ß-aminomethyl-L-alanine (BAMA) by a fully validated reverse phase chromatography-tandem mass spectrometry method. We quantified BMAA, DAB, AEG and BAMA in all of the lobster tissues. Our quantification data varied by individual lobster, sex and collection year. Significantly more BMAA was quantified in lobsters harvested in 2021 than 2022. Interestingly, more BAMA was quantified in lobsters harvested in 2022 than 2021. Monitoring of lobster harvests for cyanobacterial neurotoxins when harmful algal bloom events occur could mitigate risks to human health.
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Aminoácidos Diaminos , Decápodos , Síndromes de Neurotoxicidad , Animales , Masculino , Femenino , Humanos , Nephropidae/metabolismo , Ecosistema , Neurotoxinas/toxicidad , Aminoácidos Diaminos/metabolismo , Alimentos Marinos/análisis , Decápodos/metabolismo , beta-AlaninaRESUMEN
Isolated cervical dystonia is a focal, idiopathic dystonia affecting the neck muscles. Treatment usually consists of botulinum neurotoxin (BoNT) injections into the dystonic muscles. Our aim is to investigate the use of BoNT treatment and conservative treatments by people living with cervical dystonia. An online survey in English was conducted between June and August 2022. Participants were eligible to participate if they were living with cervical dystonia, were over 18 years old and could read and understand English. The survey consisted of demographic questions, characteristics of dystonia, questions relating to BoNT use and the perceived utility of conservative treatments. The data were analysed descriptively, and open-ended questions were grouped into similar topics represented by direct quotes. We received 128 responses from people with cervical dystonia, with an average age of 59 years and 77% women. Most participants (52%) described their cervical dystonia as mild to moderate with an average pain score of 5/10. Eighty-two (64%) participants were having regular BoNT injections, with overall positive perceived effects. Common activities reported to improve the symptoms were the use of heat packs, massage, relaxation, physiotherapy and participation in general exercise. Common coping strategies reported were getting sufficient rest, having the support of friends and family, and remaining engaged in enjoyable hobbies. We found that most participants received regular BoNT injections and that heat packs, exercise, massage, physiotherapy and relaxation were mostly perceived as effective in reducing the symptoms of cervical dystonia.
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Toxinas Botulínicas Tipo A , Trastornos Distónicos , Fármacos Neuromusculares , Tortícolis , Humanos , Femenino , Persona de Mediana Edad , Adolescente , Masculino , Tortícolis/tratamiento farmacológico , Toxinas Botulínicas Tipo A/uso terapéutico , Tratamiento Conservador , Trastornos Distónicos/tratamiento farmacológico , Neurotoxinas , Músculos del Cuello , Fármacos Neuromusculares/uso terapéutico , Resultado del TratamientoRESUMEN
The cyanobacterial non-protein amino acid (AA) ß-Methylamino-L-alanine (BMAA) is considered to be a neurotoxin. BMAA caused histopathological changes in brains and spinal cords of primates consistent with some of those seen in early motor neuron disease; however, supplementation with L-serine protected against some of those changes. We examined the impact of BMAA on AA concentrations in human neuroblastoma cells in vitro. Cells were treated with 1000 µM BMAA and intracellular free AA concentrations in treated and control cells were compared at six time-points over a 48 h culture period. BMAA had a profound effect on intracellular AA levels at specific time points but in most cases, AA homeostasis was re-established in the cell. The most heavily impacted amino acid was serine which was depleted in BMAA-treated cells from 9 h onwards. Correction of serine depletion could be a factor in the observation that supplementation with L-serine protects against BMAA toxicity in vitro and in vivo. AAs that could potentially be involved in protection against BMAA-induced oxidation such as histidine, tyrosine, and phenylalanine were depleted in cells at later time points.
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Aminoácidos Diaminos , Neuroblastoma , Animales , Humanos , Aminoácidos , Aminoácidos Diaminos/toxicidad , Aminoácidos Diaminos/metabolismo , Serina/farmacología , Neurotoxinas/toxicidadRESUMEN
Accurate targeting of overactive muscles is fundamental for successful botulinum neurotoxin (BoNT) injections in the treatment of spasticity. The necessity of instrumented guidance and the superiority of one or more guidance techniques are ambiguous. Here, we sought to investigate if guided BoNT injections lead to a better clinical outcome in adults with limb spasticity compared to non-guided injections. We also aimed to elucidate the hierarchy of common guidance techniques including electromyography, electrostimulation, manual needle placement and ultrasound. To this end, we conducted a Bayesian network meta-analysis and systematic review with 245 patients using the MetaInsight software, R and the Cochrane Review Manager. Our study provided, for the first time, quantitative evidence supporting the superiority of guided BoNT injections over the non-guided ones. The hierarchy comprised ultrasound on the first level, electrostimulation on the second, electromyography on the third and manual needle placement on the last level. The difference between ultrasound and electrostimulation was minor and, thus, appropriate contextualization is essential for decision making. Taken together, guided BoNT injections based on ultrasound and electrostimulation performed by experienced practitioners lead to a better clinical outcome within the first month post-injection in adults with limb spasticity. In the present study, ultrasound performed slightly better, but large-scale trials should shed more light on which modality is superior.
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Toxinas Botulínicas Tipo A , Fármacos Neuromusculares , Accidente Cerebrovascular , Adulto , Humanos , Teorema de Bayes , Toxinas Botulínicas Tipo A/uso terapéutico , Inyecciones Intramusculares/métodos , Espasticidad Muscular/tratamiento farmacológico , Metaanálisis en Red , Fármacos Neuromusculares/uso terapéutico , Neurotoxinas/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Resultado del TratamientoRESUMEN
INTRODUCTION: Botulinum neurotoxin injection is a valuable treatment method for patients with myofascial pain syndrome in the infraspinatus muscle. However, there is no botulinum neurotoxin injection guideline, and the most appropriate injection site based on topographical anatomic information for this injection to effectively treat myofascial pain syndrome in the infraspinatus muscle is unclear. The purpose of this study was to evaluate the intramuscular nerve terminal of the infraspinatus muscle and to suggest the most efficient botulinum neurotoxin injection sites. METHODS: This study used 5 formalin-embalmed and 10 fresh frozen cadavers with a mean age of 78.9 years. Sihler's staining was applied to evaluate the intramuscular nerve terminal of the infraspinatus muscle. The ultrasound scanning of the infraspinatus muscle was performed based on the surface landmarks and internal structures near the scapular region. RESULTS: The intramuscular nerve terminal was mostly observed in the medial third area of the infraspinatus muscle. The deltoid tubercle, inferior angle, and acromion of the scapula are useful as surface landmarks to scan the infraspinatus muscle. DISCUSSION: The proposed injection sites based on the intramuscular nerve terminal and surface landmarks can be regarded as accurate locations to reach the cluster area of the intramuscular nerve terminal and each compartment of the infraspinatus muscle to manage the myofascial pain syndrome in the infraspinatus muscle.
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Síndromes del Dolor Miofascial , Manguito de los Rotadores , Humanos , Anciano , Manguito de los Rotadores/inervación , Neurotoxinas , Escápula , Inyecciones IntramuscularesRESUMEN
As yawning is often observed in stressful or emotional situations such as tension and anxiety, this suggests that yawning can be considered to be an emotional behavior. However, the neural mechanisms underlying emotion-induced yawning remain unclear. It is well known that the hypothalamic paraventricular nucleus (PVN) is the most important brain structure for induction of yawning behavior. We previously showed that induction of yawning involves the central nucleus of the amygdala (CeA), as well as the PVN. Therefore, emotion-induced yawning could potentially be induced through activation of the direct/indirect neural pathways from the CeA to the PVN. Our present study used a combination of retrograde tracing (injection of Fluoro-Gold (FG) into the PVN) and c-Fos immunohistochemistry to examine the neural pathways that evoke emotion-induced yawning. We additionally performed lesion experiments on the CeA using ibotenic acid, a neurotoxin, to determine whether the CeA is involved in the induction of emotion-induced yawning. Emotional stress by fear conditioning induced yawning behavior, and induced expression of double-labeled cells for c-Fos and FG in the bed nucleus of the stria terminalis (BNST), but not in the CeA. Furthermore, the CeA lesions caused by ibotenic acid abolished the induction of emotion-induced yawning. These results suggest that a neural pathway from the CeA to the PVN via the BNST may be primarily involved in the induction of emotion-induced yawning behavior.
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Núcleo Amigdalino Central , Distrés Psicológico , Bostezo , Animales , Núcleo Amigdalino Central/metabolismo , Hipotálamo/metabolismo , Ácido Iboténico/farmacología , Vías Nerviosas/metabolismo , Neurotoxinas/farmacología , Núcleo Hipotalámico Paraventricular/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Estilbamidinas , Bostezo/fisiologíaRESUMEN
Pseudo-nitzschia species are one of the leading causes of harmful algal blooms (HABs) along the western coast of the United States. Approximately half of known Pseudo-nitzschia strains can produce domoic acid (DA), a neurotoxin that can negatively impact wildlife and fisheries and put human life at risk through amnesic shellfish poisoning. Production and accumulation of DA, a secondary metabolite synthesized during periods of low primary metabolism, is triggered by environmental stressors such as nutrient limitation. To quantify and estimate the feedbacks between DA production and environmental conditions, we designed a simple mechanistic model of Pseudo-nitzschia and domoic acid dynamics, which we validate against batch and chemostat experiments. Our results suggest that, as nutrients other than nitrogen (i.e., silicon, phosphorus, and potentially iron) become limiting, DA production increases. Under Si limitation, we found an approximate doubling in DA production relative to N limitation. Additionally, our model indicates a positive relationship between light and DA production. These results support the idea that the relationship with nutrient limitation and light is based on direct impacts on Pseudo-nitzschia biosynthesis and biomass accumulation. Because it can easily be embedded within existing coupled physical-ecosystem models, our model represents a step forward toward modeling the occurrence of Pseudo-nitzschia HABs and DA across the U.S. West Coast.
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Diatomeas , Neurotoxinas , Calibración , Diatomeas/metabolismo , Ecosistema , Humanos , Hierro/metabolismo , Ácido Kaínico/análogos & derivados , Neurotoxinas/metabolismo , Nitrógeno/metabolismo , Océanos y Mares , Fósforo/metabolismo , Silicio/metabolismoRESUMEN
In the rat model, 6-hydroxydopamine (6-OHDA) known as a selective catecholaminergic neurotoxin used chiefly in modeling Parkinson's disease (PD). Continuous aerobic exercise and curcumin supplementations could play a vital role in neuroprotection. This study aimed to explore the neuroprotective roles of regular aerobic exercise and curcumin during PD. For this, rats were treated as follows for 8 consecutive weeks (5 d in a week): For this, animals were orally treated with curcumin (50 ml/kg) alone or in combination with aerobic exercise. Compared with a control group, induction of PD by 6-OHDA increased the amount of alpha-synuclein protein and malondialdehyde levels and decreased the number of substantia nigra neurons, total antioxidant capacity, and glutathione peroxidase activity in brain tissue. All these changes were abolished by the administration of curcumin with aerobic exercise treatments. Activity behavioral tests also confirmed the above-mentioned results by increasing the rod test time and the number of rotations due to apomorphine injection. Histopathology assays mimic the antioxidant activity and behavioral observations. Combined curcumin with aerobic exercise treatments is potentially an effective strategy for modifying the dopaminergic neuron dysfunction in 6-OHDA-induced rats modeling PD via dual inhibiting oxidative stress indices and regulating behavioral tasks.
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Curcumina , Fármacos Neuroprotectores , Síndromes de Neurotoxicidad , Enfermedad de Parkinson , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Apomorfina/metabolismo , Apomorfina/farmacología , Curcumina/metabolismo , Curcumina/farmacología , Modelos Animales de Enfermedad , Glutatión Peroxidasa/metabolismo , Malondialdehído , Fármacos Neuroprotectores/farmacología , Neurotoxinas/metabolismo , Neurotoxinas/farmacología , Oxidopamina/toxicidad , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Ratas , Sustancia Negra , alfa-Sinucleína/metabolismoRESUMEN
Circumventricular organs (CVOs), including the mediobasal hypothalamus (MBH), have an incomplete blood-brain barrier (BBB). In this study, we determined if the BBB function in the MBH is modulated by the gut microbiota or by the Toll-like receptor (TLR) adapter proteins TRIF or MyD88 signaling. By injecting mice with Evans blue, a marker for BBB permeability, we show that germ-free (GF) and conventionally raised (CONV-R) mice did not differ in the number of Evans blue-positive cells in MBH. Acute modulation of the gut microbiota did not change the number of Evans blue-positive cells. In contrast, CONV-R Myd88-/- and Trif-/- mice had a reduced number of cells in direct contact to the circulation compared to wildtype (WT) mice. This was accompanied by increased tight junction proteins in the blood vessels in Myd88-/- mice. To further characterize the BBB function, we injected WT and Myd88 -/- CONV-R mice as well as WT GF mice with monosodium glutamate (MSG), a neurotoxin that does not cross the BBB. While MSG caused vast cell death in the MBH in CONV-R and GF WT mice, Myd88 -/- mice were protected from such cell death suggesting that fewer cells are exposed to the neurotoxin in the Myd88 -/- mice. Taken together, our results suggest that MyD88 deficiency, but not gut microbiota depletion, is sufficient to modulate the BBB function in the MBH.
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Barrera Hematoencefálica , Microbioma Gastrointestinal , Hipotálamo , Factor 88 de Diferenciación Mieloide , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Animales , Barrera Hematoencefálica/metabolismo , Azul de Evans , Hipotálamo/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/metabolismo , Neurotoxinas/toxicidad , Glutamato de Sodio/toxicidadRESUMEN
BACKGROUND: Gelsenicine, one of the most toxic alkaloids of Gelsemium elegans Benth (G. elegans), causes severe respiratory depression. However, its toxicity mechanisms are yet to be elucidated and no effective antidotes are available. OBJECTIVE: This study aimed to analyse the toxicity characteristics of gelsenicine. METHODS: Both acute and sub-acute toxicities were evaluated. Gelsenicine distribution and elimination in the central nervous system (CNS) and blood were observed. Effective antidotes for gelsenicine poisoning were screened. RESULTS: In the acute toxicity study, gelsenicine was highly toxic, and female rats exhibited greater sensitivity to gelsenicine than male rats (LD50 0.520 mg/kg vs 0.996 mg/kg, respectively). Death was primarily caused by respiratory failure. However, in the sub-acute toxicity study, no significant organ damage was observed. Gelsenicine was easily absorbed from the gastrointestinal tract and penetrated the blood-brain barrier, reaching peak concentrations in the CNS within 15 min and rapidly decreasing thereafter. Flumazenil or diazepam combined with epinephrine reversed gelsenicine toxicity and significantly improved survival rate in mice. CONCLUSIONS: Gelsenicine is a highly toxic substance that affects nerve conduction without causing damage; the potential toxic mechanism is possibly associated with GABAA receptors. Our findings provide insights into the clinical treatment of gelsenicine-related poisoning and its toxicity mechanisms.
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Antídotos/uso terapéutico , Gelsemium/química , Alcaloides Indólicos/toxicidad , Neurotoxinas/toxicidad , Extractos Vegetales/toxicidad , Insuficiencia Respiratoria/inducido químicamente , Insuficiencia Respiratoria/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Insuficiencia Respiratoria/mortalidad , Factores SexualesRESUMEN
BACKGROUND: Pediatric status epilepticus occurs in about 44/100.000 children per year with an unknown cause in about a third of patients. One cause can be the ingestion of plants containing toxins that target the central nervous system. Here we describe an ingestion of water hemlock resulting in a status epilepticus. METHODS: We studied in detail the clinical, laboratory, electrophysiological, and radiological features of a patient with status epilepticus. RESULTS: A 9-year-old boy presented to the pediatric emergency department for sudden onset of nausea, vomiting, and status epilepticus approximately one hour after the patient had bitten into the root of a water plant in an inner-city park. Bilateral tonic-clonic seizures could only be terminated after administration of midazolam, lorazepam, and finally propofol. Cranial MRI, cerebrospinal fluid, and EEG findings were largely unremarkable. The ingested plant was identified as water hemlock through a detailed search with the help of a drawing issued by the patient with the help of the medical team. The specific toxicological analysis for water hemlock verified the presence of cicutoxin and cicudiol in the blood sample. The patient was discharged, levetiracetam was weaned off four weeks later, and he has remained seizure free since. CONCLUSIONS: Given the considerable percentage of cases of unknown etiology in new-onset pediatric status epilepticus, it is important to consider plant intoxication as a possible cause.
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Cicuta/envenenamiento , Neurotoxinas/envenenamiento , Estado Epiléptico/inducido químicamente , Estado Epiléptico/diagnóstico , Niño , Humanos , MasculinoRESUMEN
Despite tremendous worldwide efforts, clinical trials assessing Alzheimer's disease (AD)-related therapeutics have been relentlessly unsuccessful. Hence, there is an urgent need to challenge old hypotheses with novel paradigms. An emerging concept is that the amyloid-beta (Aß) peptide, which was until recently deemed a major player in the cause of AD, may instead modulate synaptic plasticity and protect against excitotoxicity. The link between Aß-mediated synaptic plasticity and Aß trafficking is central for understanding AD pathogenesis and remains a perplexing relationship. The crossover between Aß pathological and physiological roles is subtle and remains controversial. Based on existing literature, as a signaling molecule, Aß is proposed to modulate its own turnover and synaptic plasticity through what is currently believed to be the cause of AD: the transient formation of pore-like oligomers. A change of perspective regarding how Aß pores exert a protective function will unavoidably revolutionize the entire field of anti-amyloid drug development.
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Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Calcio/metabolismo , Plasticidad Neuronal , Neuronas/metabolismo , Encéfalo/patología , Humanos , Neurotoxinas , Sinapsis/metabolismoRESUMEN
OBJECTIVES: Overproduction of reactive species, notably reactive oxygen (ROS) and nitrogen (RNS) species, along with the failure of balancing effects of endogenous antioxidant defenses result in destruction of cellular structures, lipids, proteins, and genetic material, which lead to oxidative stress. Oxidative stress-induced neuronal apoptosis plays a pivotal role in pathogenesis of neurodegeneration. Antioxidants represent one of the medical choice strategies for protecting against this unbalanced oxidation-antioxidation status. Recently, natural compounds with neuroprotective potential that can scavenge free radicals and protect cells from oxidative damage have received extensive attention. METHODS: In this review, we summarized the detailed research progress on the medicinal plants-derived natural compounds with potential anti-oxidation effects and their molecular mechanisms on modulating the neurotoxin (6-OHDA, H2O2, glutamate, Aß)-induced oxidative stress and cell apoptosis. RESULTS: The natural compounds that efficacious in modulating reactive species production and mitochondrial function include flavonoids, glucosides, alkaloids, polyphenols, lignans, coumarins, terpenoids, quinones and others. They decreased the neurotoxin-induced oxidative damage and apoptosis by (1) decreasing ROS/RNS generation, lipid peroxidation, caspase-3 and caspase-9 activities, LDH release, the ratio of Bax/Bcl-2, Ca2+ influx and cytochrome c release, (2) elevating MMP, and (3) restoring endogenous antioxidant enzymatic activities (CAT, GSH-Px, GSR, SOD). And they exerted neuroprotective effects against cell damages and apoptosis by modulating the oxidative cascades of different signaling pathways (Nrf2/HO-1, NF-κB, MAPKs, PI3K/Akt, GSK-3ß) and preventing mitochondria-dependent apoptosis pathways. DISCUSSION: The present work reviews the role of oxidative stress in neurodegeneration, highlighting the potential anti-oxidation effects of natural compounds as a promising approach to develop innovative neuroprotective strategy.
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Fármacos Neuroprotectores , Antioxidantes/metabolismo , Antioxidantes/farmacología , Apoptosis , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Peróxido de Hidrógeno , Fármacos Neuroprotectores/farmacología , Neurotoxinas/farmacología , Estrés Oxidativo , Fosfatidilinositol 3-Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Latrotoxins (LaTXs) are presynaptic pore-forming neurotoxins found in the venom of Latrodectus spiders. The venom contains a toxic cocktail of seven LaTXs, with one of them targeting vertebrates (α-latrotoxin (α-LTX)), five specialized on insects (α, ß, γ, δ, ε- latroinsectotoxins (LITs), and one on crustaceans (α-latrocrustatoxin (α-LCT)). LaTXs bind to specific receptors on the surface of neuronal cells, inducing the release of neurotransmitters either by directly stimulating exocytosis or by forming Ca2+-conductive tetrameric pores in the membrane. Despite extensive studies in the past decades, a high-resolution structure of a LaTX is not yet available and the precise mechanism of LaTX action remains unclear. Here, we report cryoEM structures of the α-LCT monomer and the δ-LIT dimer. The structures reveal that LaTXs are organized in four domains. A C-terminal domain of ankyrin-like repeats shields a central membrane insertion domain of six parallel α-helices. Both domains are flexibly linked via an N-terminal α-helical domain and a small ß-sheet domain. A comparison between the structures suggests that oligomerization involves major conformational changes in LaTXs with longer C-terminal domains. Based on our data we propose a cyclic mechanism of oligomerization, taking place prior membrane insertion. Both recombinant α-LCT and δ-LIT form channels in artificial membrane bilayers, that are stabilized by Ca2+ ions and allow calcium flux at negative membrane potentials. Our comparative analysis between α-LCT and δ-LIT provides first crucial insights towards understanding the molecular mechanism of the LaTX family.
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Araña Viuda Negra/química , Calcio/química , Neurotoxinas/química , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Venenos de Araña/química , Animales , Sitios de Unión , Araña Viuda Negra/patogenicidad , Calcio/metabolismo , Clonación Molecular , Microscopía por Crioelectrón , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Transporte Iónico , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Potenciales de la Membrana/fisiología , Modelos Moleculares , Neurotoxinas/genética , Neurotoxinas/metabolismo , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Venenos de Araña/genética , Venenos de Araña/metabolismoRESUMEN
The use of opioids during pregnancy has recently dramatically increased presenting major health problems, especially on the developing neonatal nervous system development. Nalufin is considered one of the most used opioid analgesics for treatment of moderate to severe pain, especially during pregnancy. The aim of the present study was firstly to assess the possible neurotoxic effects of nalufin injection during the organogenesis period of chick embryos, and second to investigate the ameliorative effects of selenium as a supplement. Fertilized chicken eggs were in ovo injected with 0.2ml of either nalufin (20 mg/kg egg) or selenium (0.1 mg/kg egg) or both. Nalufin injection resulted in cerebral cortical layer disruption, increase of Caspase-3 immunoexpression and chromatolytic nuclei, degenerated organelles, rarefied cytoplasm and hemorrhage. On the molecular levels, nalufin induced DNA fragmentation, cell cycle arrest and increased the percentage of apoptosis of the neuronal cells. Selenium combined treatment restored the three-layered structure of the cerebral cortex, decreased caspase-3 immuno-expression, improved ultrastructure and recovered cell cycle arrest, decreased apoptosis, and DNA degradation. In conclusion, nalufin treatment during pregnancy imposes great concerns and should not be used during embryonic development, on the other hands, selenium appears to be a promising neuroprotective agent against nalufin-induced neurotoxicity.
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Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Nalbufina/toxicidad , Neurotoxinas/toxicidad , Selenio/farmacología , Animales , Encéfalo/citología , Encéfalo/efectos de los fármacos , Encéfalo/patología , Embrión de Pollo , Fármacos Neuroprotectores/farmacologíaRESUMEN
Iron oxide nanoparticles (IONPs) have been proposed as targeted carriers to deliver therapeutic molecules in the central nervous system (CNS). However, IONPs may damage neural tissue via free iron accumulation, protein aggregation, and oxidative stress. Neuroprotective effects of quercetin (QC) have been proven due to its antioxidant and anti-inflammatory properties. However, poor solubility and low bioavailability of QC have also led researchers to make various QC-involved nanoparticles to overcome these limitations. We wondered how high doses or prolonged treatment with quercetin conjugated superparamagnetic iron oxide nanoparticles (QCSPIONs) could improve cognitive dysfunction and promote neurogenesis without any toxicity. It can be explained that the QC inhibits protein aggregation and acts against iron overload via iron-chelating activity, iron homeostasis genes regulation, radical scavenging, and attenuation of Fenton/Haber-Weiss reaction. In this review, first, we present brain iron homeostasis, molecular mechanisms of iron overload that induced neurotoxicity, and the role of iron in dementia-associated diseases. Then by providing evidence of IONPs neurotoxicity, we discuss how QC neutralizes IONPs neurotoxicity, and finally, we make a brief comparison between QC and conventional iron chelators. In this review, we highlight that QC as supplementation and especially in conjugated form reduces iron oxide nanoparticles neurotoxicity in clinical application.
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Encéfalo/efectos de los fármacos , Nanopartículas Magnéticas de Óxido de Hierro/toxicidad , Fármacos Neuroprotectores/farmacología , Neurotoxinas/toxicidad , Quercetina/farmacología , Animales , Encéfalo/fisiología , Modelos Animales de Enfermedad , Humanos , Hierro/metabolismo , Sobrecarga de Hierro , Ratones , Enfermedades Neurodegenerativas , RatasRESUMEN
The differences in analgesic effects of botulinum toxin type A were compared in 28 patients with trigeminal neuralgia, 53 patients with myofascial temporomandibular disorders, and 89 patients with the jaw closing oromandibular dystonia. The patients were treated by injection of botulinum toxin type A into the masseter, temporalis, medial pterygoid, and other muscles based on the symptoms of each patient. The pain severity was evaluated using the visual analog scale, pain frequency, and pain scale of the oromandibular dystonia rating scale. Botulinum toxin injection was performed 1068 times in all patients without significant adverse effects. The visual analog, pain frequency, and pain scales at baseline were reduced (p < 0.001) after two, four, eight, and 12 weeks after the first botulinum toxin therapy and at the endpoint. The effects differed significantly (p < 0.001) among the groups (repeated-measures analysis of variance). The mean improvement (0%, no effect; 100%, complete recovery) at the endpoint was 86.8% for trigeminal neuralgia, 80.8% for myofascial pain, and 75.4% for oromandibular dystonia. Injection of the botulinum toxin can be a highly effective and safe method to treat trigeminal neuralgia, myofascial pain, and oromandibular dystonia.
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Toxinas Botulínicas Tipo A/uso terapéutico , Trastornos Distónicos/tratamiento farmacológico , Síndromes del Dolor Miofascial/tratamiento farmacológico , Fármacos Neuromusculares/uso terapéutico , Neurotoxinas/uso terapéutico , Trastornos de la Articulación Temporomandibular/tratamiento farmacológico , Neuralgia del Trigémino/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Toxinas Botulínicas Tipo A/administración & dosificación , Femenino , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Manejo del Dolor/métodos , Resultado del TratamientoRESUMEN
The SH-SY5Y cell line is commonly used for the assessment of neurotoxicity in drug discovery. These neuroblastoma-derived cells can be differentiated into neurons using many methods. The present study has compared 24 of these differentiation methods on SH-SY5Y cells. After morphologic selection of the three most differentiating media (retinoic acid in 10% fetal bovine serum (FBS), staurosporine in 1% FBS medium, and cyclic adenosine monophosphate (cAMP) in B21-supplemented neurobasal medium), cells were analyzed for pan-neuronal and specific neuronal protein expression by fluorescent automated imaging. The response of SH-SY5Y to a set of compounds of known toxicity was examined in these culture conditions performed in 2D, and also in a 3D hyaluronic acid-based hydroscaffold™ which mimics the extracellular matrix. The extent of neuronal markers expression and the sensitivity to neurotoxic compounds varied according to the differentiation medium. The cAMP B21-supplemented neurobasal medium led to the higher neuronal differentiation, and the higher sensitivity to neurotoxic compounds. The culture in 3D modified the neurotoxic response, through a lower sensitivity of cells compared to the 2D culture. The in vitro differentiation environment influences the neurotoxic response of SH-SY5Y cells and thus should be considered carefully in research as well as in drug discovery.
Asunto(s)
Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Neurotoxinas/farmacología , Proliferación Celular/efectos de los fármacos , Humanos , Neuroblastoma/metabolismo , Pruebas de ToxicidadRESUMEN
Despite extensive and intensive research efforts in recent decades, there is still no effective treatment for neurodegenerative diseases. On this background, the use of drugs inhibiting the enzyme acetylcholinesterase (AChE) remains an eternal evergreen in the symptomatic treatment of mild to moderate cognitive impairments. Even more, the cholinergic hypothesis, somewhat forgotten in recent years due to the shift in focus on amyloid cascade, is back to life, and the search for new, more effective AChE inhibitors continues. We generated a fragment-based library containing aromatic moieties and linkers originating from a set of novel AChE inhibitors. We used this library to design 1220 galantamine (GAL) derivatives following the model GAL (binding core) - linker (L) - aromatic fragment (Ar). The newly designed compounds were screened virtually for blood-brain barrier (BBB) permeability and binding to AChE. Among the top 10 best-scored compounds, a representative lead molecule was selected and tested for anti-AChE activity and neurotoxicity. It was found that the selected compound was a powerful non-toxic AChE inhibitor, 68 times more active than GAL, and could serve as a lead molecule for further optimization and development.
Asunto(s)
Inhibidores de la Colinesterasa/análisis , Diseño de Fármacos , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Interfaz Usuario-Computador , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Línea Celular , Inhibidores de la Colinesterasa/química , Galantamina/química , Galantamina/farmacología , Ratones , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Neurotoxinas/toxicidad , Bibliotecas de Moléculas PequeñasRESUMEN
BACKGROUND: Most patients with scleroderma suffer from microstomia, which can have debilitating consequences on their quality of life. Unfortunately, treatment options remain limited. No specific guidelines exist; hence, microstomia remains a challenge to treat in this patient population. OBJECTIVE: This review aims to evaluate the different medical and surgical treatment modalities currently available for microstomia in patients with scleroderma and make recommendations for future research. MATERIALS AND METHODS: A search of PubMed, Ovid MEDLINE, and Ovid Embase was conducted to identify articles discussing the treatment of microstomia in scleroderma. Twenty articles discussing surgical therapy and one article discussing medical therapy were reviewed. RESULTS: Mostly because of a scarcity of high-level evidence, no individual therapy has documented long-term efficacy. Some treatments demonstrate positive results and warrant further research. CONCLUSION: Given the variability of results, specific recommendations for the treatment of microstomia in patients with scleroderma are difficult to establish. A multifaceted approach that includes surgical and medical therapy is likely the best option to improve oral aperture in this patient population. Surgical treatments such as neurotoxins, autologous fat grafting, and ultraviolet A1 phototherapy may hold the most potential for improvement.