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1.
Microb Biotechnol ; 17(4): e14468, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38635158

RESUMO

The sweet potato whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is responsible for significant crop losses and presents one of the greatest challenges for global agricultural pest management. Management of whitefly populations and associated plant viral diseases is hindered by widespread whitefly resistance to chemical insecticides. An alternative control approach involves the use of insect-specific neurotoxins, but these require delivery from the whitefly gut into the haemocoel. Here we demonstrate that the coat protein (CP) of a begomovirus, Tomato yellow leaf curl virus, is sufficient for delivery of fused proteins into the whitefly haemocoel without virion assembly. Following feeding on the recombinant CP-P-mCherry fusion (where -P- is a proline-rich linker), mCherry fluorescence was detected in the dorsal aorta and pericardial cells of the whitefly, but not in those of whitefly fed on negative control treatments, indicating effective CP-mediated delivery of mCherry into the whitefly haemocoel. Significant mortality was observed in whiteflies fed on a fusion of CP-P to the insect-specific neurotoxin Hv1a, but not in whiteflies fed on CP-P fused to a disarmed Hv1a mutant. Begomovirus coat protein - insect neurotoxin fusions hold considerable potential for transgenic resistance to whitefly providing valuable tools for whitefly management.


Assuntos
Hemípteros , Vírus de Plantas , Animais , Neurotoxinas , Agricultura , Fluorescência
2.
Sci Rep ; 14(1): 8017, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580836

RESUMO

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.


Assuntos
Diamino Aminoácidos , Decápodes , Síndromes Neurotóxicas , Animais , Masculino , Feminino , Humanos , Nephropidae/metabolismo , Ecossistema , Neurotoxinas/toxicidade , Diamino Aminoácidos/metabolismo , Alimentos Marinhos/análise , Decápodes/metabolismo , beta-Alanina
3.
Int J Mol Sci ; 25(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38542133

RESUMO

The present investigation was designed based on the evidence that, in neurodegenerative disorders, such as Alzheimer's dementia (AD) and Parkinson's disease (PD), damage to the locus coeruleus (LC) arising norepinephrine (NE) axons (LC-NE) is documented and hypothesized to foster the onset and progression of neurodegeneration within target regions. Specifically, the present experiments were designed to assess whether selective damage to LC-NE axons may alter key proteins involved in neurodegeneration within specific limbic regions, such as the hippocampus and piriform cortex, compared with the dorsal striatum. To achieve this, a loss of LC-NE axons was induced by the neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) in C57 Black mice, as assessed by a loss of NE and dopamine-beta-hydroxylase within target regions. In these experimental conditions, the amount of alpha-synuclein (alpha-syn) protein levels were increased along with alpha-syn expressing neurons within the hippocampus and piriform cortex. Similar findings were obtained concerning phospho-Tau immunoblotting. In contrast, a decrease in inducible HSP70-expressing neurons and a loss of sequestosome (p62)-expressing cells, along with a loss of these proteins at immunoblotting, were reported. The present data provide further evidence to understand why a loss of LC-NE axons may foster limbic neurodegeneration in AD and limbic engagement during PD.


Assuntos
Doença de Alzheimer , Doença de Parkinson , Camundongos , Animais , Locus Cerúleo/metabolismo , Norepinefrina/metabolismo , Neurônios/metabolismo , Neurotoxinas/farmacologia , Axônios/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Parkinson/metabolismo
4.
Sci Adv ; 10(11): eadk3870, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38478603

RESUMO

The ability of an animal to effectively capture prey and defend against predators is pivotal for survival. Venom is often a mixture of many components including toxin proteins that shape predator-prey interactions. Here, we used the sea anemone Nematostella vectensis to test the impact of toxin genotypes on predator-prey interactions. We developed a genetic manipulation technique to demonstrate that both transgenically deficient and a native Nematostella strain lacking a major neurotoxin (Nv1) have a reduced ability to defend themselves against grass shrimp, a native predator. In addition, secreted Nv1 can act indirectly in defense by attracting mummichog fish, which prey on grass shrimp. Here, we provide evidence at the molecular level of an animal-specific tritrophic interaction between a prey, its antagonist, and a predator. Last, this study reveals an evolutionary trade-off, as the reduction of Nv1 levels allows for faster growth and increased reproductive rates.


Assuntos
Anêmonas-do-Mar , Peçonhas , Animais , Reprodução , Evolução Biológica , Neurotoxinas/genética , Anêmonas-do-Mar/genética , Comportamento Predatório/fisiologia
5.
J Drugs Dermatol ; 23(3): 173-186, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38443133

RESUMO

BACKGROUND: Botulinum neurotoxin (BoNT) exhibits inhibitory effects on the neuromuscular junction, and its use is well established in cosmetic dermatology. Our review aims to analyze the evidence for its use in the treatment of various dermatological, neurological, gastroenterological, ophthalmological, otorhinolaryngological, dental, urological, gynecological, and cardiovascular disorders. METHODS: A systematic review of the literature was performed for studies published between 2012 and 2022 that discussed the therapeutic use of BoNT in human participants. A total of 58 studies were selected for inclusion in this review.  Results: We discovered a large range of therapeutic applications of BoNT toxin beyond aesthetic and US Food and Drug Administration (FDA)-approved non-aesthetic uses.  Conclusions: BoNT is a powerful neurotoxin that has varied FDA-approved indications and has been studied in a wide range of therapeutic applications. Further investigation through higher power studies is needed to assess the potential of BoNT and expand its versatility across other medical specialties.  J Drugs Dermatol. 2024;23(3):173-186. doi:10.36849/JDD.7243e.


Assuntos
Toxinas Botulínicas , Doenças Cardiovasculares , Oftalmologia , Humanos , Toxinas Botulínicas/uso terapêutico , Estética , Neurotoxinas/uso terapêutico , Estados Unidos
6.
Harmful Algae ; 133: 102602, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38485439

RESUMO

Pseudo-nitzschia is a cosmopolitan phytoplankton genus of which some species can form blooms and produce the neurotoxin domoic acid (DA). Identification of Pseudo-nitzschia is generally based on field material or strains followed by morphological and/or molecular characterization. However, this process is time-consuming and laborious, and can not obtain a relatively complete and reliable profile of the Pseudo-nitzschia community, because species with low abundance in the field or potentially unavailable for culturing may easily be overlooked. In the present study, specific ITS primer sets were designed and evaluated using in silico matching. The primer set ITS-84F/456R involving the complete ITS1 region was found optimal. Based on matching with a Pseudo-nitzschia ITS1 reference sequence database carefully-calibrated in this study, a metabarcoding approach using annotated amplicon sequence variants (ASV) was applied in the Taiwan Strait of the East China Sea during two cruises in the spring and summer of 2019. In total, 48 Pseudo-nitzschia species/phylotypes including 36 known and 12 novel were uncovered, and verified by haplotype networks, ITS2 secondary structure comparisons and divergence analyses. Correlation analyses revealed that temperature was a key factor affecting the seasonal variation of the Pseudo-nitzschia community. This study provides an overview of the Pseudo-nitzschia community in the Taiwan Strait, with new insights into the diversity. The developed metabarcoding approach may be used elsewhere as a standard reference for accurate annotation of Pseudo-nitzschia.


Assuntos
Diatomáceas , Taiwan , Diatomáceas/química , Fitoplâncton , Neurotoxinas , Estações do Ano
7.
Protein Expr Purif ; 218: 106447, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38369031

RESUMO

Diaminopropionate ammonia-lyase transforms D and L isomers of 2,3-diaminopropionate to pyruvate and ammonia. It catalyzes D- and l-serine less effectively. L-2,3-diaminopropionate is a precursor in the biosynthesis of oxalyl diaminopropionate as a neurotoxin in certain legume species. In this work, we cyclized the diaminopropionate ammonia-lyase from Salmonella typhimurium in vitro using the redox-responsive split intein, and identified that backbone cyclization afforded the enzyme with the improved activity, thermal stability and resistance to the exopeptidase proteolysis, different from effects of the incorporated sequence recognized by tobacco vein mottling virus protease at C-terminus. Using analyses of three fluorescent dyes including 8-anilino-1-naphthalenesulfonic acid, N-phenyl-1-naphthylamine, and thioflavin T, the same amounts of the cyclic protein displayed less fluorescence than those of the linear protein upon the heat treatment. The cyclic enzyme displayed the enhanced activity in Escherichia coli cells using the designed novel reporter. In this system, d-serine was added to the culture and transported into the cytoplasm. It was transformed by pre-overexpression of the diaminopropionate ammonia-lyase, and untransformed d-serine was oxidized by the coproduced human d-amino acid oxidase to generate hydrogen peroxide. This oxidant is monitored by the HyPer indicator. The current results presented that the cyclized enzyme could be applied as a better candidate to block the neurotoxin biosynthesis in certain plant species.


Assuntos
Amônia-Liases , Neurotoxinas , Salmonella typhimurium , Humanos , Ciclização , Escherichia coli/genética , Serina
9.
Environ Toxicol Pharmacol ; 107: 104399, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403141

RESUMO

ß-N-methylamino-l-alanine (BMAA) has been shown to inhibit vesicular monoamine transporter 2 (VMAT2), thereby preventing the uptake of monoaminergic neurotransmitters into platelet dense granules and synaptic vesicles. The inhibition is hypothesized to be through direct association of BMAA with hydroxyl groupꟷcontaining amino acid residues in VMAT2. This study evaluated whether BMAA-induced inhibition of VMAT2 could be prevented directly by co-incubation of BMAA with amino acids, and if this protection was specific for BMAA inhibition of VMAT2. l-tyrosine, and to a lesser extent l-serine, was able to prevent BMAA-induced VMAT2 inhibition in a concentration-dependent manner, whereas neither l-threonine nor amino acids without side chain hydroxyl groups could reduce this inhibition. Reserpine-induced VMAT2 inhibition was unaffected by any of the amino acids. These data support the hypothesized interaction between BMAA and hydroxyl groupꟷcontaining amino acids and suggests that this interaction might be leveraged to protect against the toxicity of BMAA.


Assuntos
Diamino Aminoácidos , Aminoácidos , Aminoácidos/farmacologia , Proteínas Vesiculares de Transporte de Monoamina , Diamino Aminoácidos/toxicidade , Tirosina , Neurotoxinas/metabolismo
10.
Environ Sci Pollut Res Int ; 31(15): 22885-22899, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418784

RESUMO

The aim of this study is twofold: i) to determine innovative yet sensitive endpoints for sulfoxaflor and ii) to develop best practices for innovative teaching in ecotoxicology. To this end, a group of 52 MSc students participated in an environmental hackathon, during which they did creative toxicity testing on 5 freshwater invertebrate species: Daphnia magna, Chironomus riparius, Asellus aquaticus, Lymnaea stagnalis, and Anisus vortex. Involving the students in an active learning environment stimulated increased creativity and productivity. In total, 28 endpoints were investigated, including standard endpoints (e.g., mortality) as well as biomechanistic and energy-related endpoints. Despite high variances in the results, likely linked to the limited lab experience of the students and interpersonal differences, a promising set of endpoints was selected for further investigation. A more targeted follow-up experiment focused on the most promising organism and set of endpoints: biomechanistic endpoints of C. riparius larvae. Larvae were exposed to a range of sulfoxaflor concentrations (0.90-67.2 µg/L) for 21 days. Video tracking showed that undulation and swimming were significantly reduced at 11.1 µg sulfoxaflor/L after 9 days of exposure, and an EC50 = 10.6 µg/L for mean velocities of the larvae in the water phase was found. Biomechanistic endpoints proved much more sensitive than mortality, for which an LC50 value of 116 µg/L was found on Day 9. Our results show that performing a hackathon with students has excellent potential to find sensitive endpoints that can subsequently be verified using more targeted and professional follow-up experiments. Furthermore, utilising hackathon events in teaching can increase students' enthusiasm about ecotoxicology, driving better learning experiences.


Assuntos
Neurotoxinas , Compostos de Enxofre , Poluentes Químicos da Água , Humanos , Animais , Invertebrados , Piridinas , Larva , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Daphnia
11.
Sci Total Environ ; 922: 171255, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38417517

RESUMO

The neurotoxin ß-N-methylamino-L-alanine (BMAA) has been deemed as a risk factor for some neurodegenerative diseases such as amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC). This possible link has been proved in some primate models and cell cultures with the appearance that BMAA exposure can cause excitotoxicity, formation of protein aggregates, and/or oxidative stress. The neurotoxin BMAA extensively exists in the environment and can be transferred through the food web to human beings. In this review, the occurrence, toxicological mechanisms, and characteristics of BMAA were comprehensively summarized, and proteins and peptides were speculated as its possible binding substances in biological matrices. It is difficult to compare the published data from previous studies due to the inconsistent analytical methods and components of BMAA. The binding characteristics of BMAA should be focused on to improve our understanding of its health risk to human health in the future.


Assuntos
Diamino Aminoácidos , Neurotoxinas , Animais , Humanos , Neurotoxinas/química , Diamino Aminoácidos/toxicidade , Diamino Aminoácidos/química , Toxinas de Cianobactérias , Estresse Oxidativo
12.
mBio ; 15(3): e0310623, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347673

RESUMO

Botulinum neurotoxins (BoNTs) are a class of toxins produced by Clostridium botulinum (C. botulinum) and other species of Clostridia. BoNT/X is a putative novel botulinum neurotoxin identified through genome sequencing and capable of SNARE cleavage, but its neurotoxic potential in humans and vertebrates remained unclear. The C. botulinum strain producing BoNT/X, Strain 111, encodes both a plasmid-borne bont/b2 as well as the chromosomal putative bont/x. This study utilized C. botulinum Strain 111 from Japan as well as recombinantly produced full-length BoNT/X to more fully analyze this putative pathogenic toxin. We confirmed production of full-length, catalytically active native BoNT/X by C. botulinum Strain 111, produced as a disulfide-bonded dichain polypeptide similar to other BoNTs. Both the purified native and the recombinant BoNT/X had high enzymatic activity in vitro but displayed very low potency in human-induced pluripotent stem cell-derived neuronal cells and in mice. Intraperitoneal injection of up to 50 µg of native BoNT/X in mice did not result in botulism; however, mild local paralysis was observed after injection of 2 µg into the gastrocnemius muscle. We further demonstrate that the lack of toxicity by BoNT/X is due to inefficient neuronal cell association and entry, which can be rescued by replacing the receptor binding domain of BoNT/X with that of BoNT/A. These data demonstrate that BoNT/X is not a potent vertebrate neurotoxin like the classical seven serotypes of BoNTs. IMPORTANCE: The family of botulinum neurotoxins comprises the most potent toxins known to humankind. New members of this family of protein toxins as well as more distantly related homologs are being identified. The discovery of BoNT/X via bioinformatic screen in 2017 as a putative new BoNT serotype raised concern about its potential as a pathogenic agent with no available countermeasures. This study for the first time assessed both recombinantly produced and native purified BoNT/X for its vertebrate neurotoxicity.


Assuntos
Botulismo , Clostridium botulinum , Humanos , Animais , Camundongos , Neurotoxinas/química , Neurotoxinas/genética , Neurotoxinas/metabolismo , Clostridium botulinum/genética , Plasmídeos , Neurônios/metabolismo
13.
Rev. neurol. (Ed. impr.) ; 78(4)16-28 feb., 2024. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-230631

RESUMO

Objetivo Determinar las características clínicas, electroencefalográficas, terapéuticas y evolutivas de una serie de pacientes oncopediátricos con convulsiones sintomáticas agudas. Pacientes y métodos Efectuamos un análisis descriptivo retrospectivo y prospectivo de registros clínicos de niños oncopediátricos evaluados por neurología en el Centro Ambulatorio Integral de Pacientes Hematooncológicos durante 2017-2021. Incluimos a niños de 1 mes a 17 años con tumores intracraneales y extracraneales que presentaron convulsiones sintomáticas agudas (CSA). Definimos convulsión sintomática aguda según la clasificación de la Liga Internacional contra la Epilepsia de 2010. Clasificamos las crisis epilépticas según la clasificación de la Liga Internacional contra la Epilepsia de 2017. Excluimos a todo paciente con diagnóstico de epilepsia previa y de episodios paroxísticos no epilépticos. Resultados Analizamos 44 casos, con una mediana de 4 años (rango: 1 mes-17 años) y una media de 5,75 meses (rango: 1 mes-11 meses) y 8,33 años (2-17 años). Registramos como principales etiologías la neurotoxicidad y el contexto posquirúrgico, con cuatro pacientes asociados a disnatremias y dos a hipertensión endocraneana. Se realizaron 41 electroencefalogramas, con resultados intercríticos con anormalidades en el ritmo de base, pero sin focos ni paroxismos. No hubo registros críticos. Las convulsiones focales fueron 25 (56,8%), y las generalizadas, 19 (43,18%). El levetiracetam fue el fármaco más utilizado para el tratamiento agudo. Conclusiones Nuestra cohorte muestra que las CSA, en esta población, no evidencian diferencias considerables entre convulsiones focales motoras y generalizadas, y ocurren mayormente en un contexto neurotóxico y posquirúrgico. También se registraron disnatremias e hipertensión endocraneana asociadas a CSA. Los electroencefalogramas poscrisis fueron sin focos o paroxismos y con evolución de las crisis. (AU)


AIM To determine clinical, electroencephalographic, therapeutic and evolutive characteristics of a series of oncopediatric patients with acute symptomatic seizures. PATIENTS AND METHODS We performed a retrospective and prospective descriptive analysis of clinical records of oncopediatric children evaluated by neurology at the comprehensive outpatient Center for Hemato-Oncological Patients during 2017-2021. We included children aged one month to 17 years with intracranial and extracranial tumors who presented with acute symptomatic seizure (ASC). We defined acute symptomatic seizure according to the 2010 International League Against Epilepsy. We classified seizures according to 2017 International League Against Epilepsy classification. We excluded any patient with a diagnosis of previous epilepsy and non-epileptic paroxysmal episodes. RESULTS We analyzed 44 cases with a median of 4 years (range: 1 month-17 years) and mean of 5.75 months (range: 1 month-11 months) and 8.33 years (2-17 years). The main etiologies were neurotoxicity and post-surgical context. Four patients presented dysnatremias and two associated with endocranial hypertension. Forty-one electroencephalograms were performed with intercritical results with abnormalities in the baseline rhythm, but without foci or paroxysms. There were no critical recordings. Focal seizures were 25 (56.8%) and generalized seizures 19 (43.18%). Levetiracetam was the most commonly used drug for acute management. CONCLUSIONS Our cohort shows that ASC, in this population, do not show considerable differences between focal motor and generalized seizures and occur mostly in neurotoxic and post-surgical contexts. Dysnatremias and endocranial hypertension associated with ASC were also recorded. Postcrisis electroencephalograms were without foci or paroxysms and good seizure evolution. (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Convulsões/etiologia , Oncologia , Pediatria , Período Pós-Operatório , Eletroencefalografia , Neurotoxinas , Terapêutica , Estudos Retrospectivos , Epidemiologia Descritiva , Estudos Prospectivos
14.
Cells ; 13(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38334622

RESUMO

Neuronal cell death is a key mechanism involved in the development and exacerbation of Parkinson's disease (PD). The excessive production of reactive oxygen species (ROS) is a major cause leading to neuronal death; therefore, compounds that prevent oxidative stress-dependent neuronal death may be promising as a preventive method for PD. Ergothioneine is a natural amino acid with antioxidant properties, and its protective functions in the body are attracting attention. However, there has been no investigation into the protective functions of ergothioneine using in vivo and in vitro PD models. Thus, in this study, we analyzed the efficacy of ergothioneine against 6-hydroxydopamine (6-OHDA)-dependent neuronal cell death using immortalized hypothalamic neurons (GT1-7 cells). First, we found that ergothioneine prevents 6-OHDA-dependent neuronal cell death by suppressing ROS overproduction in GT1-7 cells. The cytoprotective effect of ergothioneine was partially abolished by verapamil, an inhibitor of OCTN1, which is involved in ergothioneine uptake. Furthermore, ergothioneine-rich Rice-koji (Ergo-koji) showed cytoprotective and antioxidant effects similar to those of ergothioneine. Taken together, these results suggest that ergothioneine or foods containing ergothioneine may be an effective method for preventing the development and progression of PD.


Assuntos
Ergotioneína , Ergotioneína/farmacologia , Ergotioneína/metabolismo , Oxidopamina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Neurotoxinas/farmacologia , Morte Celular , Antioxidantes/farmacologia , Antioxidantes/metabolismo
15.
Sci Transl Med ; 16(735): eadk1867, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381847

RESUMO

Snakebite envenoming is a major global public health concern for which improved therapies are urgently needed. The antigenic diversity present in snake venom toxins from various species presents a considerable challenge to the development of a universal antivenom. Here, we used a synthetic human antibody library to find and develop an antibody that neutralizes long-chain three-finger α-neurotoxins produced by numerous medically relevant snakes. Our antibody bound diverse toxin variants with high affinity, blocked toxin binding to the nicotinic acetylcholine receptor in vitro, and protected mice from lethal venom challenge. Structural analysis of the antibody-toxin complex revealed a binding mode that mimics the receptor-toxin interaction. The overall workflow presented is generalizable for the development of antibodies that target conserved epitopes among antigenically diverse targets, and it offers a promising framework for the creation of a monoclonal antibody-based universal antivenom to treat snakebite envenoming.


Assuntos
Antivenenos , Mordeduras de Serpentes , Humanos , Animais , Camundongos , Antivenenos/química , Mordeduras de Serpentes/tratamento farmacológico , Neurotoxinas/toxicidade , Anticorpos Amplamente Neutralizantes , Venenos de Serpentes
16.
Neurotox Res ; 42(1): 11, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319410

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease in the world, the first being Alzheimer's disease. Patients with PD have a loss of dopaminergic neurons in the substantia nigra of the basal ganglia, which controls voluntary movements, causing a motor impairment as a result of dopaminergic signaling impairment. Studies have shown that mutations in several genes, such as SNCA, PARK2, PINK1, DJ-1, ATP13A2, and LRRK2, and the exposure to neurotoxic agents can potentially increase the chances of PD development. The nematode Caenorhabditis elegans (C. elegans) plays an important role in studying the risk factors, such as genetic factors, aging, exposure to chemicals, disease progression, and drug treatments for PD. C. elegans has a conserved neurotransmission system during evolution; it produces dopamine, through the eight dopaminergic neurons; it can be used to study the effect of neurotoxins and also has strains that express human α-synuclein. Furthermore, the human PD-related genes, LRK-1, PINK-1, PDR-1, DJR-1.1, and CATP-6, are present and functional in this model. Therefore, this review focuses on highlighting and discussing the use of C. elegans an in vivo model in PD-related studies. Here, we identified that nematodes exposed to the neurotoxins, such as 6-OHDA, MPTP, paraquat, and rotenone, had a progressive loss of dopaminergic neurons, dopamine deficits, and decreased survival rate. Several studies have reported that expression of human LRRK2 (G2019S) caused neurodegeneration and pink-1, pdr-1, and djr-1.1 deletion caused several effects PD-related in C. elegans, including mitochondrial dysfunctions. Of note, the deletion of catp-6 in nematodes caused behavioral dysfunction, mitochondrial damage, and reduced survival. In addition, nematodes expressing α-synuclein had neurodegeneration and dopamine-dependent deficits. Therefore, C. elegans can be considered an accurate animal model of PD that can be used to elucidate to assess the underlying mechanisms implicated in PD to find novel therapeutic targets.


Assuntos
Proteínas de Caenorhabditis elegans , Doenças Neurodegenerativas , Doença de Parkinson , Animais , Humanos , Doença de Parkinson/genética , alfa-Sinucleína/genética , Caenorhabditis elegans , Neurotoxinas , Dopamina , Adenosina Trifosfatases , Proteínas de Caenorhabditis elegans/genética
17.
Toxins (Basel) ; 16(2)2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393153

RESUMO

Cnidarians (corals, sea anemones, and jellyfish) produce toxins that play central roles in key ecological processes, including predation, defense, and competition, being the oldest extant venomous animal lineage. Cnidaria small cysteine-rich proteins (SCRiPs) were the first family of neurotoxins detected in stony corals, one of the ocean's most crucial foundation species. Yet, their molecular evolution remains poorly understood. Moreover, the lack of a clear classification system has hindered the establishment of an accurate and phylogenetically informed nomenclature. In this study, we extensively surveyed 117 genomes and 103 transcriptomes of cnidarians to identify orthologous SCRiP gene sequences. We annotated a total of 168 novel putative SCRiPs from over 36 species of stony corals and 12 species of sea anemones. Phylogenetic reconstruction identified four distinct SCRiP subfamilies, according to strict discrimination criteria based on well-supported monophyly with a high percentage of nucleotide and amino acids' identity. Although there is a high prevalence of purifying selection for most SCRiP subfamilies, with few positively selected sites detected, a subset of Acroporidae sequences is influenced by diversifying positive selection, suggesting potential neofunctionalizations related to the fine-tuning of toxin potency. We propose a new nomenclature classification system relying on the phylogenetic distribution and evolution of SCRiPs across Anthozoa, which will further assist future proteomic and functional research efforts.


Assuntos
Antozoários , Cnidários , Anêmonas-do-Mar , Animais , Antozoários/genética , Anêmonas-do-Mar/genética , Cnidários/genética , Neurotoxinas/genética , Cisteína/genética , Filogenia , Proteômica
18.
Toxins (Basel) ; 16(2)2024 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-38393175

RESUMO

Since its regulatory approval over a half-century ago, botulinum toxin has evolved from one of the most potent neurotoxins known to becoming routinely adopted in clinical practice. Botulinum toxin, a highly potent neurotoxin produced by Clostridium botulinum, can cause botulism illness, characterized by widespread muscle weakness due to inhibition of acetylcholine transmission at neuromuscular junctions. The observation of botulinum toxin's anticholinergic properties led to the investigation of its potential benefits for conditions with an underlying etiology of cholinergic transmission, including autonomic nervous system dysfunction. These conditions range from disorders of the integument to gastrointestinal and urinary systems. Several formulations of botulinum toxin have been developed and tested over time, significantly increasing the availability of this treatment for appropriate clinical use. Despite the accelerated and expanded use of botulinum toxin, there lacks an updated comprehensive review on its therapeutic use, particularly to treat autonomic dysfunction. This narrative review provides an overview of the effect of botulinum toxin in the treatment of autonomic dysfunction and summarizes the different formulations and dosages most widely studied, while highlighting reported outcomes and the occurrence of any adverse events.


Assuntos
Doenças do Sistema Nervoso Autônomo , Toxinas Botulínicas , Botulismo , Clostridium botulinum , Humanos , Toxinas Botulínicas/efeitos adversos , Botulismo/terapia , Neurotoxinas , Doenças do Sistema Nervoso Autônomo/tratamento farmacológico
19.
Int J Mol Sci ; 25(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38255772

RESUMO

Parkinson's disease (PD) is a complex disorder characterized by the impairment of the dopaminergic nigrostriatal system. PD has duplicated its global burden in the last few years, becoming the leading neurological disability worldwide. Therefore, there is an urgent need to develop innovative approaches that target multifactorial underlying causes to potentially prevent or limit disease progression. Accumulating evidence suggests that neuroinflammatory responses may play a pivotal role in the neurodegenerative processes that occur during the development of PD. Cortistatin is a neuropeptide that has shown potent anti-inflammatory and immunoregulatory effects in preclinical models of autoimmune and neuroinflammatory disorders. The goal of this study was to explore the therapeutic potential of cortistatin in a well-established preclinical mouse model of PD induced by acute exposure to the neurotoxin 1-methil-4-phenyl1-1,2,3,6-tetrahydropyridine (MPTP). We observed that treatment with cortistatin mitigated the MPTP-induced loss of dopaminergic neurons in the substantia nigra and their connections to the striatum. Consequently, cortistatin administration improved the locomotor activity of animals intoxicated with MPTP. In addition, cortistatin diminished the presence and activation of glial cells in the affected brain regions of MPTP-treated mice, reduced the production of immune mediators, and promoted the expression of neurotrophic factors in the striatum. In an in vitro model of PD, treatment with cortistatin also demonstrated a reduction in the cell death of dopaminergic neurons that were exposed to the neurotoxin. Taken together, these findings suggest that cortistatin could emerge as a promising new therapeutic agent that combines anti-inflammatory and neuroprotective properties to regulate the progression of PD at multiple levels.


Assuntos
Neuropeptídeos , Doença de Parkinson , Animais , Camundongos , Doença de Parkinson/tratamento farmacológico , Neurotoxinas , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
20.
Plant Physiol Biochem ; 207: 108388, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38295528

RESUMO

Grass pea has the potential to become a miracle crop if the stigma attached to it as a toxic plant is ignored. In light of the following, we conducted transcriptome analyses on the high and low ODAP-containing cultivars i.e., Nirmal and Bidhan respectively in both normal and salt stress conditions. In this study, genes that work upstream and downstream to ß-ODAP have been found. Among these genes, AAO3 and ACL5 were related to ABA and polyamine biosynthesis, showing the relevance of ABA and polyamines in boosting the ß-ODAP content in Nirmal. Elevated ß-ODAP levels in salt stress-treated Bidhan may have evolved tolerance by positively regulating the expression of genes involved in phenylpropanoid and jasmonic acid biosynthesis. Although the concentration of ß-ODAP in Bidhan increased under salt stress, it was lower than in stress-treated Nirmal. Despite this, the expression of stress-related genes that work downstream to ß-ODAP was found higher in stress-treated Bidhan. This could be because stress-treated Nirmal has lower GSH, proline, and higher H2O2, resulting in the development of severe oxidative stress. Overall, our research not only identified new genes linked with ß-ODAP, but also revealed the molecular mechanism by which a low ß-ODAP-containing cultivar developed tolerance against salinity stress.


Assuntos
Diamino Aminoácidos , Lathyrus , Lathyrus/genética , Lathyrus/metabolismo , Neurotoxinas/análise , Neurotoxinas/metabolismo , Diamino Aminoácidos/análise , Diamino Aminoácidos/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Salino/genética
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