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1.
Res Nurs Health ; 47(2): 234-241, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38281085

RESUMEN

The purpose of this study was to examine the impact of a culturally based intervention, the Intertribal Talking Circle program, compared to a standard alcohol and drug abuse education, the Be A Winner program. Community-based participatory research was used to implement a two-condition, quasi-experimental study. The sample included 540 Native American youth ages 10-12 years old from three tribal areas in the United States. Data were collected at baseline, 6 and 12-months post-intervention for both the intervention and control groups using demographic, cultural identity, alcohol use, and drug use questionnaires. Regression models evaluated participants' improvement in decreasing alcohol and drug use and increasing cultural identity. Findings revealed that alcohol and drug use decreased more significantly among youth who participated in the Intertribal Talking Circle (ITC) intervention program than youth who participated in a standard alcohol and drug abuse education Be A Winner (BAW) program. Cultural identity also increased more significantly among participants who completed the Talking Circle intervention program. Native American youth ages 10-12 years old respond positively to a culturally based intervention for the reduction of alcohol and drug use. The findings highlight the importance of cultural values and identity and their significance in preventing and reducing alcohol and drug use among Native American youth.


Asunto(s)
Indio Americano o Nativo de Alaska , Trastornos Relacionados con Sustancias , Niño , Humanos , Educación en Salud , Trastornos Relacionados con Sustancias/prevención & control , Encuestas y Cuestionarios , Estados Unidos , Asistencia Sanitaria Culturalmente Competente
2.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36674850

RESUMEN

The trafficking of transient receptor potential (TRP) channels to the plasma membrane and the release of calcitonin gene-related peptide (CGRP) from trigeminal ganglion neurons (TGNs) are implicated in some aspects of chronic migraines. These exocytotic processes are inhibited by cleavage of SNAREs with botulinum neurotoxins (BoNTs); moreover, type A toxin (/A) clinically reduces the frequency and severity of migraine attacks but not in all patients for unknown reasons. Herein, neonatal rat TGNs were stimulated with allyl isothiocyanate (AITC), a TRPA1 agonist, and dose relationships were established to link the resultant exocytosis of CGRP with Ca2+ influx. The CGRP release, quantified by ELISA, was best fit by a two-site model (EC50 of 6 and 93 µM) that correlates with elevations in intracellular Ca2+ [Ca2+]i revealed by time-lapse confocal microscopy of fluo-4-acetoxymethyl ester (Fluo-4 AM) loaded cells. These signals were all blocked by two TRPA1 antagonists, HC-030031 and A967079. At low [AITC], [Ca2+]i was limited because of desensitisation to the agonist but rose for concentrations > 0.1 mM due to a deduced non-desensitising second phase of Ca2+ influx. A recombinant BoNT chimera (/DA), which cleaves VAMP1/2/3, inhibited AITC-elicited CGRP release to a greater extent than SNAP-25-cleaving BoNT/A. /DA also proved more efficacious against CGRP efflux evoked by a TRPV1 agonist, capsaicin. Nerve growth factor (NGF), a pain-inducing sensitiser of TGNs, enhanced the CGRP exocytosis induced by low [AITC] only. Both toxins blocked NGF-induced neuropeptide secretion and its enhancement of the response to AITC. In conclusion, NGF sensitisation of sensory neurons involves TRPA1, elevated Ca2+ influx, and CGRP exocytosis, mediated by VAMP1/2/3 and SNAP-25 which can be attenuated by the BoNTs.


Asunto(s)
Toxinas Botulínicas , Canales de Potencial de Receptor Transitorio , Ratas , Animales , Péptido Relacionado con Gen de Calcitonina/farmacología , Péptido Relacionado con Gen de Calcitonina/metabolismo , Proteína 1 de Membrana Asociada a Vesículas/metabolismo , Factor de Crecimiento Nervioso/farmacología , Factor de Crecimiento Nervioso/metabolismo , Toxinas Botulínicas/metabolismo , Células Receptoras Sensoriales/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Canal Catiónico TRPA1/metabolismo
3.
Plant Dis ; 106(8): 2228-2238, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34978874

RESUMEN

Meta-analysis was used to compare yield protection and nematode suppression provided by two seed-applied and two soil-applied nematicides against Meloidogyne incognita and Rotylenchulus reniformis on cotton across 3 years and several trial locations in the U.S. Cotton Belt. Nematicides consisted of thiodicarb- and fluopyram-treated seed, aldicarb and fluopyram applied in furrow, and combinations of the seed treatments and soil-applied fluopyram. The nematicides had no effect on nematode reproduction or root infection but had a significant impact on seed cotton yield response ([Formula: see text]), with an average increase of 176 and 197 kg/ha relative to the nontreated control in M. incognita and R. reniformis infested fields, respectively. However, because of significant variation in yield protection and nematode suppression by nematicides, five or six moderator variables (cultivar resistance [M. incognita only], nematode infestation level, nematicide treatment, application method, trial location, and growing season) were used depending on nematode species. In M. incognita-infested fields, greater yield protection was observed with nematicides applied in furrow and with seed-applied + in-furrow than with solo seed-applied nematicide applications. Most notable of these in-furrow nematicides were aldicarb and fluopyram (>131 g/ha) with or without a seed-applied nematicide compared with thiodicarb. In R. reniformis-infested fields, moderator variables provided no further explanation of the variation in yield response produced by nematicides. Furthermore, moderator variables provided little explanation of the variation in nematode suppression by nematicides in M. incognita- and R. reniformis-infested fields. The limited explanation by the moderator variables on the field efficacy of nematicides in M. incognita- and R. reniformis-infested fields demonstrates the difficulty of managing these pathogens with nonfumigant nematicides across the U.S. Cotton Belt.


Asunto(s)
Antinematodos , Tylenchoidea , Aldicarb/toxicidad , Animales , Antinematodos/toxicidad , Benzamidas/toxicidad , Gossypium , Piridinas/toxicidad , Semillas , Suelo , Tylenchoidea/efectos de los fármacos , Tylenchoidea/fisiología , Estados Unidos
4.
Int J Mol Sci ; 23(2)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35055082

RESUMEN

Nerve growth factor (NGF) is known to intensify pain in various ways, so perturbing pertinent effects without negating its essential influences on neuronal functions could help the search for much-needed analgesics. Towards this goal, cultured neurons from neonatal rat trigeminal ganglia-a locus for craniofacial sensory nerves-were used to examine how NGF affects the Ca2+-dependent release of a pain mediator, calcitonin gene-related peptide (CGRP), that is triggered by activating a key signal transducer, transient receptor potential vanilloid 1 (TRPV1) with capsaicin (CAP). Measurements utilised neurons fed with or deprived of NGF for 2 days. Acute re-introduction of NGF induced Ca2+-dependent CGRP exocytosis that was inhibited by botulinum neurotoxin type A (BoNT/A) or a chimera of/E and/A (/EA), which truncated SNAP-25 (synaptosomal-associated protein with Mr = 25 k) at distinct sites. NGF additionally caused a Ca2+-independent enhancement of the neuropeptide release evoked by low concentrations (<100 nM) of CAP, but only marginally increased the peak response to ≥100 nM. Notably, BoNT/A inhibited CGRP exocytosis evoked by low but not high CAP concentrations, whereas/EA effectively reduced responses up to 1 µM CAP and inhibited to a greater extent its enhancement by NGF. In addition to establishing that sensitisation of sensory neurons to CAP by NGF is dependent on SNARE-mediated membrane fusion, insights were gleaned into the differential ability of two regions in the C-terminus of SNAP-25 (181-197 and 198-206) to support CAP-evoked Ca2+-dependent exocytosis at different intensities of stimulation.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/biosíntesis , Capsaicina/farmacología , Factor de Crecimiento Nervioso/metabolismo , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Ganglio del Trigémino/efectos de los fármacos , Ganglio del Trigémino/metabolismo , Animales , Toxinas Botulínicas Tipo A/farmacología , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Exocitosis/efectos de los fármacos , Factor de Crecimiento Nervioso/farmacología , Proteolisis , Ratas , Proteína 25 Asociada a Sinaptosomas/metabolismo
5.
Cell Physiol Biochem ; 55(4): 428-448, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-34242501

RESUMEN

BACKGROUND/AIMS: Nociceptors detect noxious capsaicin (CAPS) via the transient receptor potential vanilloid 1 (TRPV1) ion channel, but coding mechanisms for relaying CAPS concentration [CAPS] remain obscure. Prolonged (up to 1h.) exposure to CAPS is used clinically to desensitise sensory fibres for treatment of neuropathic pain, but its signalling has typically been studied in cultures of dissociated sensory neurons employing low cell numbers and very short exposure times. Thus, it was pertinent to examine responses to longer CAPS exposures in large populations of adult neurons. METHODS: Confocal fluorescence microscopy was used to monitor the simultaneous excitation by CAPS of neuronal populations in intact L3/4 dorsal root ganglia (DRG) explants from adult pirt-GCaMP3 mice that express a cytoplasmic, genetically-encoded Ca2+ sensor in almost all primary sensory neurons. Peak analysis was performed using GraphPad Prism 9 to deconstruct the heterogenous and complex fluorescence signals observed into informative, readily-comparable measurements: number of signals, their lag time, maximum intensity relative to baseline (Max.) and duration. RESULTS: Exposure for 5 min. to CAPS activated plasmalemmal TRPV1 and led to increased fluorescence due to Ca2+ entry into DRG neurons (DRGNs), as it was prevented by capsazepine or removal of extracellular Ca2+. Increasing [CAPS] (0.3, 1 and 10 µM, respectively) evoked signals from more neurons (123, 275 and 390 from 5 DRG) with shorter average lag (6.4 ± 0.4, 3.3 ± 0.2 and 1.9 ± 0.1 min.) and longer duration (1.4 ± 0.2, 2.9 ± 0.2 and 4.8 ± 0.3 min.). Whilst raising [CAPS] produced a modest augmentation of Max. for individual neurons, those with large increases were selectively expedited; this contributed to a faster onset and higher peak of cumulative fluorescence for an enlarged responding neuronal population. CAPS caused many cells to fluctuate between high and low levels of fluorescence, with consecutive pulses increasing Max. and duration especially when exposure was extended from 5 to 20 min. Such signal facilitation counteracted tachyphylaxis, observed upon repeated exposure to 1 µM CAPS, preserving the cumulative fluorescence over time (signal density) in the population. CONCLUSION: Individual neurons within DRG differed extensively in the dynamics of response to CAPS, but systematic changes elicited by elevating [CAPS] increased signal density in a graded manner, unveiling a possible mechanism for population coding of responses to noxious chemicals. Signal density is sustained during prolonged and repeated exposure to CAPS, despite profound tachyphylaxis in some neurons, by signal facilitation in others. This may explain the burning sensation that persists for several hours when CAPS is used clinically.


Asunto(s)
Calcio/metabolismo , Capsaicina/farmacología , Ganglios Espinales/metabolismo , Nociceptores/metabolismo , Transducción de Señal/efectos de los fármacos , Canales Catiónicos TRPV/metabolismo , Animales , Femenino , Ganglios Espinales/citología , Masculino , Ratones , Ratones Transgénicos , Nociceptores/citología , Transducción de Señal/genética , Canales Catiónicos TRPV/genética
6.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33806699

RESUMEN

Nociceptors sense hazards via plasmalemmal cation channels, including transient receptor potential vanilloid 1 (TRPV1). Nerve growth factor (NGF) sensitises TRPV1 to capsaicin (CAPS), modulates nociceptor excitability and induces thermal hyperalgesia, but cellular mechanisms remain unclear. Confocal microscopy was used to image changes in intracellular Ca2+ concentration ([Ca2+]i) across neuronal populations in dorsal root ganglia (DRG) explants from pirt-GCaMP3 adult mice, which express a fluorescent reporter in their sensory neurons. Raised [Ca2+]i was detected in 84 neurons of three DRG explants exposed to NGF (100 ng/mL) and most (96%) of these were also excited by 1 µM CAPS. NGF elevated [Ca2+]i in about one-third of the neurons stimulated by 1 µM CAPS, whether applied before or after the latter. In neurons excitable by NGF, CAPS-evoked [Ca2+]i signals appeared significantly sooner (e.g., respective lags of 1.0 ± 0.1 and 1.9 ± 0.1 min), were much (>30%) brighter and lasted longer (6.6 ± 0.4 vs. 3.9 ± 0.2 min) relative to those non-responsive to the neurotrophin. CAPS tachyphylaxis lowered signal intensity by ~60% but was largely prevented by NGF. Increasing CAPS from 1 to 10 µM nearly doubled the number of cells activated but only modestly increased the amount co-activated by NGF. In conclusion, a sub-population of the CAPS-sensitive neurons in adult mouse DRG that can be excited by NGF is more sensitive to CAPS, responds with stronger signals and is further sensitised by transient exposure to the neurotrophin.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Calcio/metabolismo , Capsaicina/farmacología , Ganglios Espinales/efectos de los fármacos , Factor de Crecimiento Nervioso/farmacología , Neuronas/efectos de los fármacos , Nocicepción/efectos de los fármacos , Animales , Femenino , Ganglios Espinales/metabolismo , Hiperalgesia/metabolismo , Masculino , Ratones , Factores de Crecimiento Nervioso/metabolismo , Neuronas/metabolismo , Nociceptores/metabolismo , Transducción de Señal/efectos de los fármacos , Canales Catiónicos TRPV/metabolismo
7.
Health Promot Pract ; 22(6): 778-785, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-32406286

RESUMEN

Background. Substance use among American Indians (AIs) is a critical health issue and accounts for many health problems such as chronic liver disease, cirrhosis, behavioral health conditions, homicide, suicide, and motor vehicle accidents. In 2013, the highest rates of substance use and dependence were seen among AIs when compared to all other population groups, although these rates vary across different tribes. Among AI adolescents, high rates of substance use have been associated with environmental and historical factors, including poverty, historical trauma, bicultural stress, and changing tribal/familial roles. Our project, the Intertribal Talking Circle intervention, involved adapting, tailoring, implementing, and evaluating an existing intervention for AI youth of three tribal communities in the United States. Formative Results. Community partnership committees (CPCs) identified alcohol, marijuana, and prescription medications as high priority substances. CPC concerns focused on the increasing substance use in their communities and the corresponding negative impacts on families, stating a lack of coping skills, positive role models, and hope for the future as concerns for youth. Cultural Tailoring Process Results. Each site formed a CPC that culturally tailored the intervention for their tribal community. This included translating Keetoowah-Cherokee language, cultural practices, and symbolism into the local tribal customs for relevance. The CPCs were essential for incorporating local context and perceived concerns around AI adolescent substance use. These results may be helpful to other tribal communities developing/implementing substance use prevention interventions for AI youth. It is critical that Indigenous cultures and local context be factored into such programs.


Asunto(s)
Indígenas Norteamericanos , Trastornos Relacionados con Sustancias , Suicidio , Adolescente , Cultura , Humanos , Trastornos Relacionados con Sustancias/prevención & control , Estados Unidos , Indio Americano o Nativo de Alaska
8.
Prev Sci ; 21(Suppl 1): 54-64, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30397737

RESUMEN

Given the paucity of empirically based health promotion interventions designed by and for American Indian, Alaska Native, and Native Hawaiian (i.e., Native) communities, researchers and partnering communities have had to rely on the adaptation of evidence-based interventions (EBIs) designed for non-Native populations, a decidedly sub-optimal approach. Native communities have called for development of Indigenous health promotion programs in which their cultural worldviews and protocols are prioritized in the design, development, testing, and implementation. There is limited information regarding how Native communities and scholars have successfully collaborated to design and implement culturally based prevention efforts "from the ground up." Drawing on five diverse community-based Native health intervention studies, we describe strategies for designing and implementing culturally grounded models of health promotion developed in partnership with Native communities. Additionally, we highlight indigenist worldviews and protocols that undergird Native health interventions with an emphasis on the incorporation of (1) original instructions, (2) relational restoration, (3) narrative-[em]bodied transformation, and (4) indigenist community-based participatory research (ICBPR) processes. Finally, we demonstrate how culturally grounded interventions can improve population health when they prioritize local Indigenous knowledge and health-positive messages for individual to multi-level community interventions.


Asunto(s)
Competencia Cultural , Promoción de la Salud/métodos , Indígenas Norteamericanos , Nativos de Hawái y Otras Islas del Pacífico , Desarrollo de Programa/métodos , Femenino , Equidad en Salud , Humanos , Masculino , Estados Unidos
9.
Bioconjug Chem ; 28(6): 1684-1692, 2017 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-28489355

RESUMEN

Numerous naturally occurring toxins can perturb biological systems when they invade susceptible cells. Coupling of pertinent targeting ligands to the active domains of such proteins provides a strategy for directing these to particular cellular populations implicated in disease. A novel approach described herein involved fusion of one mutated immunoglobulin G (IgG) binding moiety of staphylococcal protein A to the SNARE protease and translocation domain of botulinum neurotoxin A (BoNT/A). This chimera could be monovalently coupled to IgG or via its Fc region to recombinant targeting ligands. The utility of the resulting conjugates is demonstrated by the delivery of a SNARE protease into a cell line expressing tropomyosin receptor kinase A (TrkA) through coupling to anti-TrkA IgG or a fusion of Fc and nerve-growth factor. Thus, this is a versitile and innovative technology for conjugating toxins to diverse ligands for retargeted cell delivery of potential therapeutics.


Asunto(s)
Toxinas Botulínicas Tipo A/química , Inmunoglobulina G/química , Proteínas SNARE/metabolismo , Sitios de Unión , Sistemas de Liberación de Medicamentos , Fragmentos Fc de Inmunoglobulinas , Inmunoglobulina G/metabolismo , Factor de Crecimiento Nervioso/inmunología , Receptor trkA/inmunología , Vacunas
10.
Plant Dis ; 101(5): 774-784, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-30678579

RESUMEN

In the past decade, increased attention has been placed on biological control of plant-parasitic nematodes using various fungi and bacteria. The objectives of this study were to evaluate the potential of 662 plant growth-promoting rhizobacteria (PGPR) strains for mortality to Meloidogyne incognita J2 in vitro and for nematode management in greenhouse, microplot, and field trials. Results indicated that the mortality of M. incognita J2 by the PGPR strains ranged from 0 to 100% with an average of 39%. Among the PGPR strains examined, 212 of 662 strains (or 33%) caused significantly greater mortality percent of M. incognita J2 than the untreated control. Bacillus was the major genus initiating a greater mortality percentage when compared with the other genera. In subsequent trials, B. velezensis strain Bve2 reduced M. incognita eggs per gram of cotton root in the greenhouse trials at 45 days after planting (DAP) similarly to the commercial standards Abamectin and Clothianidin plus B. firmus I-1582. Bacillus mojavensis strain Bmo3, B. velezensis strain Bve2, B. subtilis subsp. subtilis strain Bsssu3, and the Mixture 2 (Abamectin + Bve2 + B. altitudinis strain Bal13) suppressed M. incognita eggs per gram of root in the microplot at 45 DAP. Bacillus velezensis strains Bve2 and Bve12 also increased seed-cotton yield in the microplot and field trials. Overall, results indicate that B. velezensis strains Bve2 and Bve12, B. mojavensis strain Bmo3, and Mixture 2 have potential to reduce M. incognita population density and to enhance growth of cotton when applied as in-furrow sprays at planting.

11.
Plant Mol Biol ; 85(1-2): 107-21, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24452833

RESUMEN

A Glycine max syntaxin 31 homolog (Gm-SYP38) was identified as being expressed in nematode-induced feeding structures known as syncytia undergoing an incompatible interaction with the plant parasitic nematode Heterodera glycines. The observed Gm-SYP38 expression was consistent with prior gene expression analyses that identified the alpha soluble NSF attachment protein (Gm-α-SNAP) resistance gene because homologs of these genes physically interact and function together in other genetic systems. Syntaxin 31 is a protein that resides on the cis face of the Golgi apparatus and binds α-SNAP-like proteins, but has no known role in resistance. Experiments presented here show Gm-α-SNAP overexpression induces Gm-SYP38 transcription. Overexpression of Gm-SYP38 rescues G. max [Williams 82/PI 518671], genetically rhg1 (-/-), by suppressing H. glycines parasitism. In contrast, Gm-SYP38 RNAi in the rhg1 (+/+) genotype G. max [Peking/PI 548402] increases susceptibility. Gm-α-SNAP and Gm-SYP38 overexpression induce the transcriptional activity of the cytoplasmic receptor-like kinase BOTRYTIS INDUCED KINASE 1 (Gm-BIK1-6) which is a family of defense proteins known to anchor to membranes through a 5' MGXXXS/T(R) N-myristoylation sequence. Gm-BIK1-6 had been identified previously by RNA-seq experiments as expressed in syncytia undergoing an incompatible reaction. Gm-BIK1-6 overexpression rescues the resistant phenotype. In contrast, Gm-BIK1-6 RNAi increases parasitism. The analysis demonstrates a role for syntaxin 31-like genes in resistance that until now was not known.


Asunto(s)
Genes de Plantas , Glycine max/parasitología , Interacciones Huésped-Parásitos , Nematodos/patogenicidad , Proteínas Qa-SNARE/fisiología , Animales , Clonación Molecular , Proteínas Qa-SNARE/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Glycine max/genética
12.
FASEB J ; 27(8): 3167-80, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23640057

RESUMEN

Proteins responsible for basal and stimulated endocytosis in nerves containing small clear synaptic vesicles (SCSVs) or large dense-core vesicles (LDCVs) are revealed herein, using probes that exploit surface-exposed vesicle proteins as acceptors for internalization. Basal uptake of botulinum neurotoxins (BoNTs) by both SCSV-releasing cerebellar granule neurons (CGNs) and LDCV-enriched trigeminal ganglionic neurons (TGNs) was found to require protein acceptors and acidic compartments. In addition, dynamin, clathrin, adaptor protein complex-2 (AP2), and amphiphysin contribute to the depolarization-evoked entry. For fast recycling of SCSVs, knockdown and knockout strategies demonstrated that CGNs use predominantly dynamin 1, whereas isoform 2 and, to a smaller extent, isoform 3 support a less rapid mode of stimulated endocytosis. Accordingly, proximity ligation assay confirmed that dynamin 1 and 2 colocalize with amphiphysin 1 in CGNs, and the latter copurified with both dynamins from cell extracts. In contrast, LDCV-releasing TGNs preferentially employ dynamins 2 and 3 and amphiphysin 1 for evoked endocytosis and lack the fast phase. Hence, stimulation recruits dynamin, clathrin, AP2, and amphiphysin to augment BoNT internalization, and neurons match endocytosis mediators to the different demands for locally recycling SCSVs or replenishing distally synthesized LDCVs.


Asunto(s)
Toxinas Botulínicas/metabolismo , Endocitosis , Neuronas/metabolismo , Neurotoxinas/metabolismo , Complejo 2 de Proteína Adaptadora/genética , Complejo 2 de Proteína Adaptadora/metabolismo , Subunidades alfa de Complejo de Proteína Adaptadora/genética , Subunidades alfa de Complejo de Proteína Adaptadora/metabolismo , Animales , Toxinas Botulínicas/genética , Toxinas Botulínicas Tipo A , Células Cultivadas , Clatrina/genética , Clatrina/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Ácido Glutámico/metabolismo , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Microscopía Confocal , Mutación , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/citología , Neurotoxinas/genética , Péptidos/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Interferencia de ARN , Ratas , Ratas Sprague-Dawley , Vesículas Secretoras/metabolismo , Vesículas Sinápticas/metabolismo
13.
Neurourol Urodyn ; 33 Suppl 3: S14-20, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25042137

RESUMEN

The utility of botulinum neurotoxin type A (BoNT/A) for treating overactive muscles and endocrine glands is attributable to a unique conflation of properties honed to exploit and inactivate synaptic transmission. Specific, high-affinity coincident binding to gangliosides plus an intraluminal loop of synaptic vesicle protein 2 (SV2) by the heavy chain (HC) of BoNT/A confers selectivity for presynaptic nerve terminals and subsequent uptake by endocytosis. Upon vesicle acidification, the HC forms a channel for transmembrane transfer of the light chain to the cytosol, as observed by single channel recordings. The light chain is a Zn(2+) -dependent endoprotease that cleaves and inactivates SNAP-25, thereby blocking exocytotic release of transmitters, a discovery that revealed the pivotal role of the latter in synaptic vesicle fusion. A di-leucine motif in BoNT/A light chain stabilizes this protease, contributing to its longevity inside nerves. The ubiquity of SV2 and SNAP-25 has prompted re-evaluation of the nerve types susceptible to BoNT/A. In urology, there is emerging evidence that BoNT/A blocks neuropeptide release from afferent nerves, exocytosis of acetylcholine and purines from efferent nerves, and possibly ATP release from the urothelium. Suppression by BoNT/A of the surface expression of nociceptor channels on bladder afferents might also contribute to its improvement of urological sensory symptoms.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Fármacos Neuromusculares/uso terapéutico , Terminales Presinápticos/efectos de los fármacos , Vejiga Urinaria Neurogénica/tratamiento farmacológico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/inervación , Animales , Toxinas Botulínicas Tipo A/efectos adversos , Vías Eferentes/efectos de los fármacos , Vías Eferentes/metabolismo , Vías Eferentes/fisiopatología , Endocitosis/efectos de los fármacos , Exocitosis/efectos de los fármacos , Humanos , Fármacos Neuromusculares/efectos adversos , Terminales Presinápticos/metabolismo , Transmisión Sináptica/efectos de los fármacos , Resultado del Tratamiento , Vejiga Urinaria Neurogénica/diagnóstico , Vejiga Urinaria Neurogénica/metabolismo , Vejiga Urinaria Neurogénica/fisiopatología , Vejiga Urinaria Hiperactiva/diagnóstico , Vejiga Urinaria Hiperactiva/metabolismo , Vejiga Urinaria Hiperactiva/fisiopatología
14.
FASEB J ; 26(12): 5035-48, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22942075

RESUMEN

Botulinum neurotoxin (BoNT) A or E and tetanus toxin (TeTx) bind to motor-nerve endings and undergo distinct trafficking; their light-chain (LC) proteases cleave soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) peripherally or centrally and cause flaccid or spastic paralysis, respectively. To seek protein domains responsible for local blockade of transmitter release (BoNTs) rather than retroaxonal transport to spinal neurons (TeTx), their acceptor-binding moieties (H(C))--or in one case, heavy chain (HC)--were exchanged by gene recombination. Each chimera, expressed and purified from Escherichia coli, entered rat cerebellar neurons to cleave their substrates, blocked in vitro nerve-induced muscle contractions, and produced only flaccid paralysis in mice. Thus, the local cytosolic delivery of BoNT/A or BoNT/E proteases and the contrasting retrograde transport of TeTx are not specified solely by their HC or H(C); BoNT/A LC translocated locally irrespective of being targeted by either of the latter TeTx domains. In contrast, BoNT/E protease fused to a TeTx enzymatically inactive mutant (TeTIM) caused spastic paralysis and cleaved SNAP-25 in spinal cord but not the injected muscle. Apparently, TeTIM precludes cytosolic release of BoNT/E protease at motor nerve endings. It is deduced that the LCs of the toxins, acting in conjunction with HC domains, dictate their local or distant destinations.


Asunto(s)
Toxinas Botulínicas/metabolismo , Parálisis/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Toxina Tetánica/metabolismo , Animales , Western Blotting , Toxinas Botulínicas/genética , Toxinas Botulínicas/farmacocinética , Cerebelo/metabolismo , Ratones , Mutación , Enfermedades Neuromusculares/metabolismo , Neuronas/metabolismo , Neurotoxinas/genética , Neurotoxinas/metabolismo , Neurotoxinas/farmacocinética , Péptido Hidrolasas/metabolismo , Transporte de Proteínas , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/farmacocinética , Nervio Ciático/fisiopatología , Nervio Ciático/cirugía , Médula Espinal/metabolismo , Proteína 25 Asociada a Sinaptosomas/metabolismo , Toxina Tetánica/genética , Toxina Tetánica/farmacocinética
15.
Biochem J ; 441(1): 443-52, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21929507

RESUMEN

Intracellular protein transport routes can be studied using toxins that exploit these to enter cells. BoNTA (botulinum neurotoxin type A) is a protease that binds to peripheral nerve terminals, becomes endocytosed and causes prolonged blockade of transmitter release by cleaving SNAP-25 (synaptosome-associated protein of 25 kDa). Retrograde transport of the toxin has been suggested, but not of the transient muscle relaxant, BoNTE (botulinum neurotoxin type E). In the present study, dispersal of these proteases in compartmented cultures of rat sympathetic neurons was examined after focal application of BoNTA or BoNTE to neurites. A majority of cleaved SNAP-25 was seen locally, but some appeared along neurites and accumulated in the soma over several weeks. BoNTE yielded less cleaved SNAP-25 at distal sites due to shorter-lived enzymic activity. Neurite transection prevented movement of BoNTA. The BoNTA protease could be detected only in the supernatants of neurites or cell body lysates, hence these proteases must move along neuronal processes in the axoplasm or are reversibly associated with membranes. Substitution into BoNTE of the BoNTA acceptor-binding domain did not alter its potency or mobility. Spontaneous or evoked transmission to cell bodies were not inhibited by retrogradely migrated BoNTA except with high doses, concurring with the lack of evidence for a direct central action when used clinically.


Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Toxinas Botulínicas/farmacología , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Transmisión Sináptica/efectos de los fármacos , Animales , Animales Recién Nacidos , Toxinas Botulínicas/metabolismo , Toxinas Botulínicas Tipo A/metabolismo , Células Cultivadas , Regulación de la Expresión Génica/fisiología , Transporte de Proteínas , Ratas , Proteína 25 Asociada a Sinaptosomas/genética , Proteína 25 Asociada a Sinaptosomas/metabolismo
16.
Toxins (Basel) ; 15(5)2023 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-37235366

RESUMEN

Some 14% of global prevalence, based on high-income country populations, suffers from migraine. Chronic migraine is very disabling, being characterized by at least 15 headache days per month of which at least 8 days present the features of migraine. Onabotulinumtoxin A, targeting the machinery for exocytosis of neurotransmitters and neuropeptides, has been approved for use in chronic migraine since 2010. This systematic review and meta-analysis appraises the safety of onabotulinumtoxin A treatment for chronic migraine and the occurrence of treatment-related adverse events (TRAEs) in randomized, clinical studies in comparison with placebo or other comparators and preventative treatments according to the most updated Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 recommendations. The search retrieved 888 total records. Nine studies are included and seven were eligible for meta-analysis. The present study demonstrates that toxin produces more TRAEs than placebo, but less than oral topiramate, supporting the safety of onabotulinumtoxin A, and highlights the heterogeneity of the studies present in the literature (I2 = 96%; p < 0.00001). This points to the need for further, adequately powered, randomized clinical trials assessing the safety of onabotulinumtoxin A in combination with the newest treatment options.


Asunto(s)
Toxinas Botulínicas Tipo A , Trastornos Migrañosos , Humanos , Toxinas Botulínicas Tipo A/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Trastornos Migrañosos/tratamiento farmacológico , Cefalea/tratamiento farmacológico
17.
Psychiatry Res Neuroimaging ; 335: 111712, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37660442

RESUMEN

Research suggests that traditional cultural factors are protective against mental health conditions in American Indian (AI) populations. This study aims to determine if cognitive control is a neurocognitive mechanism of the protective role of spirituality in AI people with generalized anxiety disorder (GAD). Participants self-identified as AI (n = 52) and included individuals with GAD (n = 16) and without GAD (n = 36). Electroencephalography was collected during a stop-signal task to probe cognitive control using the P3 event-related potential. Higher levels of spirituality attenuated the processing efficiency disruption among individuals with GAD as indicated by P3 amplitudes closer to that of individuals without GAD.


Asunto(s)
Indio Americano o Nativo de Alaska , Trastornos de Ansiedad , Espiritualidad , Humanos , Trastornos de Ansiedad/psicología , Cognición , Electroencefalografía , Potenciales Evocados
18.
J Biol Chem ; 286(8): 6375-85, 2011 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-21138836

RESUMEN

Blockade of neurotransmitter release by botulinum neurotoxin type A (BoNT(A)) underlies the severe neuroparalytic symptoms of human botulism, which can last a few years. The structural basis for this remarkable persistence remains unclear. Herein, recombinant BoNT(A) was found to match the neurotoxicity of that from Clostridium botulinum, producing persistent cleavage of synaptosomal-associated protein of 25 kDa (SNAP-25) and neuromuscular paralysis. When two leucines near the C terminus of the protease light chain of A (LC(A)) were mutated, its inhibition of exocytosis was followed by fast recovery of intact SNAP-25 in cerebellar neurons and neuromuscular transmission in vivo. Deletion of 6-7 N terminus residues diminished BoNT(A) activity but did not alter the longevity of its SNAP-25 cleavage and neuromuscular paralysis. Furthermore, genetically fusing LC(E) to a BoNT(A) enzymically inactive mutant (BoTIM(A)) yielded a novel LC(E)-BoTIM(A) protein that targets neurons, and the BoTIM(A) moiety also delivers and stabilizes the inhibitory LC(E), giving a potent and persistent cleavage of SNAP-25 with associated neuromuscular paralysis. Moreover, its neurotropism was extended to sensory neurons normally insensitive to BoNT(E). LC(E-)BoTIM(A)(AA) with the above-identified dileucine mutated gave transient neuromuscular paralysis similar to BoNT(E), reaffirming that these residues are critical for the persistent action of LC(E)-BoTIM(A) as well as BoNT(A). LC(E)-BoTIM(A) inhibited release of calcitonin gene-related peptide from sensory neurons mediated by transient receptor potential vanilloid type 1 and attenuated capsaicin-evoked nociceptive behavior in rats, following intraplantar injection. Thus, a long acting, versatile composite toxin has been developed with therapeutic potential for pain and conditions caused by overactive cholinergic nerves.


Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Cerebelo/metabolismo , Leucina , Fármacos Neuromusculares/farmacología , Proteínas Recombinantes de Fusión/farmacología , Células Receptoras Sensoriales/metabolismo , Transmisión Sináptica/efectos de los fármacos , Animales , Toxinas Botulínicas Tipo A/genética , Calcitonina/genética , Calcitonina/metabolismo , Cerebelo/citología , Femenino , Masculino , Ratones , Mutación , Estructura Terciaria de Proteína , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes de Fusión/genética , Células Receptoras Sensoriales/citología , Proteína 25 Asociada a Sinaptosomas/genética , Proteína 25 Asociada a Sinaptosomas/metabolismo , Factores de Tiempo
19.
Plant Mol Biol ; 80(2): 131-55, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22689004

RESUMEN

Transcriptional mapping experiments of the major soybean cyst nematode resistance locus, rhg1, identified expression of the vesicular transport machinery component, α soluble NSF attachment protein (α-SNAP), occurring during defense. Sequencing the α-SNAP coding regions from the resistant genotypes G. max ([Peking/PI 548402]) and G. max ([PI 437654]) revealed they are identical, but differ from the susceptible G. max ([Williams 82/PI 518671]) by the presence of several single nucleotide polymorphisms. Using G. max ([Williams 82/PI 518671]) as a reference, a G â†’ T(2,822) transversion in the genomic DNA sequence at a functional splice site of the α-SNAP([Peking/PI 548402]) allele produced an additional 17 nucleotides of mRNA sequence that contains an in-frame stop codon caused by a downstream G â†’ A(2,832) transition. The G. max ([Peking/PI 548402]) genotype has cell wall appositions (CWAs), structures identified as forming as part of a defense response by the activity of the vesicular transport machinery. In contrast, the 17 nt α-SNAP([Peking/PI 548402]) mRNA motif is not found in G. max ([PI 88788]) that exhibits defense to H. glycines, but lack CWAs. The α-SNAP([PI 88788]) promoter contains sequence elements that are nearly identical to the α-SNAP([Peking/PI 548402]) allele, but differs from the G. max ([Williams 82/PI 518671]) ortholog. Overexpressing the α-SNAP([Peking/PI 548402]) allele in the susceptible G. max ([Williams 82/PI 518671]) genotype suppressed H. glycines infection. The experiments indicate a role for the vesicular transport machinery during infection of soybean by the soybean cyst nematode. However, increased GmEREBP1, PR1, PR2, PR5 gene activity but suppressed PR3 expression accompanied the overexpression of the α-SNAP([Peking/PI 548402]) allele prior to infection.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Glycine max/genética , Proteínas de Plantas/genética , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida/genética , Alelos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Resistencia a la Enfermedad/genética , Genotipo , Interacciones Huésped-Parásitos , Datos de Secuencia Molecular , Mutación , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/parasitología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida/metabolismo , Glycine max/clasificación , Glycine max/parasitología , Especificidad de la Especie , Tylenchoidea/fisiología
20.
Toxins (Basel) ; 14(2)2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-35202143

RESUMEN

Chimeras of botulinum neurotoxin (BoNT) serotype A (/A) combined with /E protease might possess improved analgesic properties relative to either parent, due to inheriting the sensory neurotropism of the former with more extensive disabling of SNAP-25 from the latter. Hence, fusions of /E protease light chain (LC) to whole BoNT/A (LC/E-BoNT/A), and of the LC plus translocation domain (HN) of /E with the neuronal acceptor binding moiety (HC) of /A (BoNT/EA), created previously by gene recombination and expression in E. coli., were used. LC/E-BoNT/A (75 units/kg) injected into the whisker pad of rats seemed devoid of systemic toxicity, as reflected by an absence of weight loss, but inhibited the nocifensive behavior (grooming, freezing, and reduced mobility) induced by activating TRPV1 with capsaicin, injected at various days thereafter. No sex-related differences were observed. c-Fos expression was increased five-fold in the trigeminal nucleus caudalis ipsi-lateral to capsaicin injection, relative to the contra-lateral side and vehicle-treated controls, and this increase was virtually prevented by LC/E-BoNT/A. In vitro, LC/E-BoNT/A or /EA diminished CGRP exocytosis from rat neonate trigeminal ganglionic neurons stimulated with up to 1 µM capsaicin, whereas BoNT/A only substantially reduced the release in response to 0.1 µM or less of the stimulant, in accordance with the /E protease being known to prevent fusion of exocytotic vesicles.


Asunto(s)
Analgésicos/farmacología , Toxinas Botulínicas Tipo A/farmacología , Capsaicina/farmacología , Neurotoxinas/farmacología , Células Receptoras Sensoriales/efectos de los fármacos , Animales , Animales Recién Nacidos , Conducta Animal/efectos de los fármacos , Péptido Relacionado con Gen de Calcitonina/metabolismo , Femenino , Masculino , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Dolor/metabolismo , Ratas Sprague-Dawley , Células Receptoras Sensoriales/metabolismo , Proteína 25 Asociada a Sinaptosomas/metabolismo , Ganglio del Trigémino/citología
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