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1.
Brain Res ; 1844: 149134, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39097217

RESUMEN

RATIONALE: The prelimbic division (PrL) of the medial prefrontal cortex (mPFC) is a key structure in panic. OBJECTIVES: To evaluate the role of nitric oxide (NO) in defensive behaviour and antinociception. METHODS: Either Nω-propyl-L-arginine (NPLA) or Carboxy-PTIO was microinjected in the PrL cortex, followed by hypothalamic treatment with bicuculline. The exploratory behaviours, defensive reactions and defensive antinociception were recorded. Encephalic c-Fos protein was immunolabelled after escape behaviour. RESULTS: NPLA (an inhibition of nNOs) decreased panic-like responses and innate fear-induced antinociception. The c-PTIO (a membrane-impermeable NO scavenger) decreased the escape behaviour. PrL cortex pre-treatment with c-PTIO at all doses decreased defensive antinociception. c-Fos protein was labelled in neocortical areas, limbic system, and mesencephalic structures. CONCLUSION: The NPLA and c-PTIO in the PrL/mPFC decreased the escape behaviour and defensive antinociception organised by medial hypothalamic nuclei. The oriented escape behaviour recruits neocortical areas, limbic system, and mesencephalic structures. These findings suggest that the organisation of defensive antinociception recruits NO-signalling mechanisms within the PrL cortex. Furthermore, the present findings also support the role of NO as a retrograde messenger in the PrL cortex during panic-like emotional reactions.


Asunto(s)
Óxido Nítrico , Pánico , Corteza Prefrontal , Proteínas Proto-Oncogénicas c-fos , Ratas Wistar , Animales , Masculino , Óxido Nítrico/metabolismo , Pánico/fisiología , Pánico/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Corteza Prefrontal/efectos de los fármacos , Arginina/farmacología , Arginina/análogos & derivados , Transducción de Señal/fisiología , Transducción de Señal/efectos de los fármacos , Reacción de Fuga/fisiología , Reacción de Fuga/efectos de los fármacos , Bicuculina/farmacología , Benzoatos , Imidazoles
2.
Methods Mol Biol ; 2831: 351-375, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39134862

RESUMEN

Fluorescent and non-fluorescent neural tract tracers enable the investigation of neural pathways in both peripheral and central nervous systems in laboratory animals demonstrating images with high resolution and great anatomic precision. Anterograde and retrograde viral tracers are important cutting-edge tools for neuroanatomical mapping. The optogenetic consists of an advanced alternative for in vivo neural tract tracing procedures, fundamentally considering the possibility to dissect and modulate pathways either exciting or inhibiting neural circuits in laboratory animals. The neurotractography by diffusion tensor imaging in vivo procedures enables the study of neural pathways in humans with reasonable accuracy. Here we describe the procedure of classical anatomic neural tract tracing and modern optogenetic technique performed in anima vili in addition to different diffusion tensor neurotractography performed in anima nobili.


Asunto(s)
Imagen de Difusión Tensora , Optogenética , Optogenética/métodos , Animales , Imagen de Difusión Tensora/métodos , Técnicas de Trazados de Vías Neuroanatómicas/métodos , Vías Nerviosas , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Encéfalo/metabolismo , Trazadores del Tracto Neuronal , Humanos , Ratones
3.
Artículo en Inglés | MEDLINE | ID: mdl-38797491

RESUMEN

BACKGROUND AND PURPOSE: Chronic neuropathic pain (NP) is commonly associated with cognitive and emotional impairments. Cannabidiol (CBD) presents a broad spectrum of action with a potential analgesic effect. This work investigates the CBD effect on comorbidity between chronic NP, depression, and memory impairment. EXPERIMENTAL APPROACH: The connection between the neocortex and the hippocampus was investigated with biotinylated dextran amine (BDA) deposits in the prelimbic cortex (PrL). Wistar rats were submitted to chronic constriction injury (CCI) of the sciatic nerve and CA1 treatment with CBD (15, 30, 60 nmol). KEY RESULTS: BDA-labeled perikarya and terminal buttons were found in CA1 and dentate gyrus. CCI-induced mechanical and cold allodynia increased c-Fos protein expression in the PrL and CA1. The number of astrocytes in PrL and CA1 increased, and the number of neuroblasts decreased in CA1. Animals submitted to CCI procedure showed increasing depressive-like behaviors, such as memory impairment. CBD (60 nmol) treatment decreased mechanical and cold allodynia, attenuated depressive-associated behaviors, and improved memory performance. Cobalt chloride (CoCl2: 1 nM), WAY-100635 (0.37 nmol), and AM251 (100 nmol) intra-PrL reversed the effect of CA1 treatment with CBD (60 nmol) on nociceptive, cognitive, and depressive behaviors. CONCLUSION: CBD represents a promising therapeutic perspective in the pharmacological treatment of chronic NP and associated comorbidities such as depression and memory impairments. The CBD effects possibly recruit the CA1-PrL pathway, inducing neuroplasticity. CBD acute treatment into the CA1 produces functional and molecular morphological improvements.


Asunto(s)
Cannabidiol , Disfunción Cognitiva , Hipocampo , Neocórtex , Neuralgia , Ratas Wistar , Animales , Cannabidiol/farmacología , Cannabidiol/uso terapéutico , Masculino , Neuralgia/tratamiento farmacológico , Ratas , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Neocórtex/efectos de los fármacos , Hiperalgesia/tratamiento farmacológico , Vías Nerviosas/efectos de los fármacos , Síntomas Afectivos/tratamiento farmacológico , Síntomas Afectivos/etiología
4.
Sci Rep ; 14(1): 455, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172384

RESUMEN

The Asian Citrus Psyllid (ACP), Diaphorina citri, is a vector of the pathological bacterium Candidatus Liberibacter asiaticus (CLas), which causes the most devastating disease to the citrus industry worldwide, known as greening or huanglongbing (HLB). Earlier field tests with an acetic acid-based lure in greening-free, 'Valencia' citrus orange groves in California showed promising results. The same type of lures tested in São Paulo, Brazil, showed unsettling results. During the unsuccessful trials, we noticed a relatively large proportion of females in the field, ultimately leading us to test field-collected males and females for Wolbachia and CLas. The results showed high rates of Wolbachia and CLas infection in field populations. We then compared the olfactory responses of laboratory-raised, CLas-free, and CLas-infected males to acetic acid. As previously reported, CLas-uninfected males responded to acetic acid at 1 µg. Surprisingly, CLas-infected males required 50 × higher doses of the putative sex pheromone, thus explaining the failure to capture CLas-infected males in the field. CLas infection was also manifested in electrophysiological responses. Electroantennogram responses from CLas-infected ACP males were significantly higher than those obtained with uninfected males. To the best of our knowledge, this is the first report of a pathogen infection affecting a vector's response to a sex attractant.


Asunto(s)
Citrus sinensis , Citrus , Hemípteros , Rhizobiaceae , Atractivos Sexuales , Wolbachia , Femenino , Masculino , Animales , Hemípteros/fisiología , Atractivos Sexuales/farmacología , Brasil , Citrus/microbiología , Rhizobiaceae/fisiología , Acetatos , Enfermedades de las Plantas/microbiología
5.
Neurosci Lett ; 820: 137572, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38072029

RESUMEN

BACKGROUND: Haloperidol (HAL) is an antipsychotic used in the treatment of schizophrenia. However, adverse effects are observed in the extrapyramidal tracts due to its systemic action. Natural compounds are among the treatment alternatives widely available in Brazilian biodiversity. Mygalin (MY), a polyamine that was synthesized from a natural molecule present in the hemolymph of the Acanthoscurria gomesian spider, may present an interesting approach. AIMS: This study aimed to evaluate the effect of MY in mice subjected to HAL-induced catalepsy. METHODS: Male Swiss mice were used. Catalepsy was induced by intraperitoneal administration of HAL (0.5 mg/kg - 1 mL/Kg) diluted in physiological saline. To assess the MY effects on catalepsy, mice were assigned to 4 groups: (1) physiological saline (NaCl 0.9 %); (2) MY at 0.002 mg/Kg; (3) MY at 0.02 mg/Kg; (4) MY at 0.2 mg/Kg. MY or saline was administered intraperitoneally (IP) 10 min b HAL before saline. Catalepsy was evaluated using the bar test at 15, 30, 60, 90, and 120 min after the IP administration of HAL. RESULTS: The latency time in the bar test 15, 30, 60, and 90 min increased (p < 0.05) after IP administration of HAL compared to the control group. Catalepsy was attenuated 15, 30, 90, and 120 min (p < 0.05) after the IP-administration of MY at 0.2 mg/Kg; while MY at 0.02 mg/Kg attenuated catalepsy 15 min after the HAL treatment. Our findings showed that MY attenuates the HAL-induced cataleptic state in mice.


Asunto(s)
Antipsicóticos , Arañas , Ratones , Masculino , Animales , Haloperidol/farmacología , Catalepsia/inducido químicamente , Catalepsia/tratamiento farmacológico , Antipsicóticos/efectos adversos
6.
Exp Brain Res ; 241(11-12): 2591-2604, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37725136

RESUMEN

Neuropathic pain (NP) represents a complex disorder with sensory, cognitive, and emotional symptoms. The medial prefrontal cortex (mPFC) takes critical regulatory roles and may change functionally and morphologically during chronic NP. There needs to be a complete understanding of the neurophysiological and psychopharmacological bases of the NP phenomenon. This study aimed to investigate the participation of the infralimbic division (IFL) of the mPFC in chronic NP, as well as the role of the N-methyl-D-aspartic acid receptor (NMDAr) in the elaboration of chronic NP. Male Wistar rats were submitted to the von Frey and acetone tests to assess mechanical and cold allodynia after 21 days of chronic constriction injury (CCI) of the sciatic nerve or Sham-procedure ("false operated"). Electrical neurostimulation of the IFL/mPFC was performed by low-frequency stimuli (20 µA, 100 Hz) applied for 15 s by deep brain stimulation (DBS) device 21 days after CCI. Either cobalt chloride (CoCl2 at 1.0 mM/200 nL), NMDAr agonist (at 0.25, 1.0, and 2.0 nmol/200 nL) or physiological saline (200 nL) was administered into the IFL/mPFC. CoCl2 administration in the IFL cortex did not alter either mechanical or cold allodynia. DBS stimulation of the IFL cortex decreased mechanical allodynia in CCI rats. Chemical stimulation of the IFL cortex by an NMDA agonist (at 2.0 nmol) decreased mechanical allodynia. NMDA at any dose (0.25, 1.0, and 2.0 nmol) reduced the flicking/licking duration in the cold test. These findings suggest that the IFL/mPFC and the NMDAr of the neocortex are involved in attenuating chronic NP in rats.


Asunto(s)
Hiperalgesia , Neuralgia , Ratas , Masculino , Animales , N-Metilaspartato/farmacología , Dimensión del Dolor , Ratas Wistar , Neuralgia/terapia , Receptores de N-Metil-D-Aspartato/metabolismo , Corteza Prefrontal/metabolismo
8.
J Med Chem ; 66(15): 10273-10288, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37499118

RESUMEN

Histone deacetylase 6 (HDAC6) inhibition is an attractive strategy for treating numerous cancers, and HDAC6 catalytic inhibitors are currently in clinical trials. The HDAC6 zinc-finger ubiquitin-binding domain (UBD) binds free C-terminal diglycine motifs of unanchored ubiquitin polymer chains and protein aggregates, playing an important role in autophagy and aggresome assembly. However, targeting this domain with small molecule antagonists remains an underdeveloped avenue of HDAC6-focused drug discovery. We report SGC-UBD253 (25), a chemical probe potently targeting HDAC6-UBD in vitro with selectivity over nine other UBDs, except for weak USP16 binding. In cells, 25 is an effective antagonist of HDAC6-UBD at 1 µM, with marked proteome-wide selectivity. We identified SGC-UBD253N (32), a methylated derivative of 25 that is 300-fold less active, serving as a negative control. Together, 25 and 32 could enable further exploration of the biological function of the HDAC6-UBD and investigation of the therapeutic potential of targeting this domain.


Asunto(s)
Ubiquitina , Ubiquitinas , Histona Desacetilasa 6 , Inhibidores de Histona Desacetilasas/farmacología , Unión Proteica , Ubiquitina/metabolismo , Dedos de Zinc
9.
J Comput Aided Mol Des ; 37(9): 407-418, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37378817

RESUMEN

Kallikrein 6 (KLK6) is an attractive drug target for the treatment of neurological diseases and for various cancers. Herein, we explore the accuracy and efficiency of different computational methods and protocols to predict the free energy of binding (ΔGbind) for a series of 49 inhibitors of KLK6. We found that the performance of the methods varied strongly with the tested system. For only one of the three KLK6 datasets, the docking scores obtained with rDock were in good agreement (R2 ≥ 0.5) with experimental values of ΔGbind. A similar result was obtained with MM/GBSA (using the ff14SB force field) calculations based on single minimized structures. Improved binding affinity predictions were obtained with the free energy perturbation (FEP) method, with an overall MUE and RMSE of 0.53 and 0.68 kcal/mol, respectively. Furthermore, in a simulation of a real-world drug discovery project, FEP was able to rank the most potent compounds at the top of the list. These results indicate that FEP can be a promising tool for the structure-based optimization of KLK6 inhibitors.


Asunto(s)
Descubrimiento de Drogas , Simulación de Dinámica Molecular , Termodinámica , Entropía , Simulación del Acoplamiento Molecular , Unión Proteica , Ligandos
10.
J Biochem Mol Toxicol ; 37(7): e23353, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37069807

RESUMEN

Depression has a high rate of comorbidity with neuropathic pain. This study aims to investigate the effect of Mygalin, an acylpolyamine synthesized from a natural molecule in the hemolymph of the Acanthoscurria gomesiana spider, injected into the prelimbic (PrL) region of the medial prefrontal cortex on chronic neuropathic pain and depression comorbidity in rats. To investigate that comorbidity, neuropathic pain was induced by chronic constriction injury (CCI) of the sciatic nerve in male Wistar rats. The biotinylated biodextran amine (BDA) bidirectional neural tract tracer was microinjected into the PrL cortex to study brain connections. Rodents were further subjected to von Frey (mechanical allodynia), acetone (cold allodynia), and forced swim (depressive-like behavior) tests. BDA neural tract tracer-labeled perikarya were found in the dorsal columns of the periaqueductal gray matter (dPAG) and the dorsal raphe nucleus (DRN). Neuronal activity of DRN neurons decreased in CCI rats. However, PrL cortex treatment with Mygalin increased the number of spikes on DRN neurons. Mygalin treatment in the PrL cortex decreased both mechanical and cold allodynia and immobility behavior in CCI rats. PrL cortex treatment with N-methyl-D-aspartate (NMDA) receptor receptors attenuated the analgesic and antidepressive effects caused by Mygalin. The PrL cortex is connected with the dPAG and DRN, and Mygalin administration into the PrL increased the activity of DRN neurons. Mygalin in the PrL cortex produced antinociceptive and antidepressive-like effects, and the NMDA agonist reversed these effects.


Asunto(s)
Neuralgia , Arañas , Ratas , Masculino , Animales , Depresión , Hiperalgesia , N-Metilaspartato/farmacología , Ratas Wistar , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Receptores de N-Metil-D-Aspartato , Comorbilidad , Corteza Prefrontal
11.
Neuromodulation ; 26(8): 1622-1636, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36057495

RESUMEN

BACKGROUND AND AIMS: The dysgranula parts of the posterior insular cortex (PIC) stimulation (PICS) has been investigated as a new putative cortical target for nonpharmacologic therapies in patients with chronic and neuropathic pain (NP). This work investigates the neural bases of insula neurostimulation-induced antinociception and glutamatergic neurochemical mechanisms recruited by the PICS in animals with neuropathy. MATERIALS AND METHODS: Male Wistar rats were submitted to the von Frey and acetone tests to assess mechanical and cold allodynia after 21 days of chronic constriction injury (CCI) of the sciatic nerve or Sham procedure ("false operated"). Either the Cascade Blue 3000 MW lysine-fixable dextran (CBD) or the biotinylated dextran amine 3000 MW (BDA) neural tract tracer was microinjected into the PIC. The electrical PICS was performed at a low frequency (20 µA, 100 Hz) for 15 seconds by a deep brain stimulation device. PIC N-methyl-D-aspartate (NMDA) receptors (NMDAR) blockade with the selective antagonist LY235959 (at 2, 4, and 8 nmol/200 nL) followed by PICS was investigated in rats with CCI. RESULTS: PIC sends projections to the caudal pontine reticular nucleus, alpha part of the parvicellular reticular nucleus, dorsomedial tegmental area, and secondary somatosensory cortex (S2). PICS decreased both mechanical and cold allodynia in rats with chronic NP. Blockade of NMDAR in the PIC with LY235959 at 8 nmol attenuated PICS-produced antinociception. CONCLUSION: Neuroanatomic projections from the PIC to pontine reticular nuclei and S2 may contribute to chronic NP signaling. PICS attenuates the chronic NP, and the NMDA glutamatergic system in the PIC may be involved in PICS-induced antinociception in rodents with NP conditions.


Asunto(s)
N-Metilaspartato , Neuralgia , Humanos , Ratas , Masculino , Animales , N-Metilaspartato/uso terapéutico , Hiperalgesia/terapia , Corteza Insular , Ratas Wistar , Neuralgia/tratamiento farmacológico , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/uso terapéutico
12.
Behav Brain Res ; 424: 113803, 2022 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-35189173

RESUMEN

INTRODUCTION: Morphological reorganization in the neural networks of the medial prefrontal cortex (mPFC) may be involved in the development of chronic neuropathic pain (NP). OBJECTIVES: We investigated whether inactivation and neurostimulation of the infralimbic division (IFL) of the mPFC alter electroacupuncture-induced analgesia (EIA) at 2 Hz and 2/100 Hz in animals with chronic NP. METHODS: Wistar rats were submitted to chronic constrictor injury of the ischiadicus nerve (CCI). Von Frey and acetone tests were performed to evaluate mechanical or cold allodynia. Animals were submitted to electroacupuncture (EA) at 2 Hz and 2/100 Hz for 20 min. After EA, the IFL cortex synaptic contacts were inactivated by cobalt chloride (200 nL of 1.0 mM CoCl2). Neurostimulation of the IFL cortex was also performed at 20 µA for 15 s, after EA, using a deep brain stimulation device. RESULTS: EA at 2 Hz and 2/100 Hz attenuated mechanical or cold allodynia in CCI rats. Microinjection of CoCl2 into the IFL division of the mPFC blocked the EA effect. EA at 2 Hz and 2/100 Hz, in association with neurostimulation of the IFL cortex, attenuated mechanical and thermal allodynia. CONCLUSION: EA induces antinociception in CCI rats. The analgesia was potentiated in association with neurostimulation in the IFL division of the mPFC.


Asunto(s)
Dolor Crónico , Electroacupuntura , Neuralgia , Animales , Dolor Crónico/terapia , Hiperalgesia/terapia , Neuralgia/terapia , Corteza Prefrontal , Ratas , Ratas Wistar
13.
J Fish Biol ; 100(3): 811-819, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35043986

RESUMEN

South Brazil's archaeological coastal sites (shellmounds and middens) show a diverse collection of shark faunal remains, some of which belong to species considered rare nowadays for the region. However, shark archaeological remains identification in this region has been historically insufficient and prone to mistakes. This study identified shark fauna and estimated body size (total length) present at two archaeological sites: Rio do Meio (1220-977 Cal B.P.) and Enseada II (4286-3783 Cal B.P.), located in Santa Catarina, South of Brazil. Here, 1600 teeth and 3588 vertebrae were analysed and identified. We showed higher historical shark species richness than previously reported for South Brazil in historical and archaeological studies. In total, we identified at least 15 species of sharks (11 species and four identifications at the genus level). The presence of juvenile shark remains adds to the evidence of pre-colonial fishing impacts in local shark populations. The consistent recovery of adults and juveniles of Carcharias taurus points to a possible nursery area on the mouth of Babitonga bay. The high teeth frequency (43%) of C. taurus suggests the South Brazil coastline was once home to abundant populations of this critically endangered species. Furthermore, we discuss the presence of rare species nowadays, suggesting a possible historical residency for adult populations of Carcharodon carcharias based on the presence of juveniles and young-of-the-year on archaeological sites. The occurrence of Negaprion brevirostris, a tropical species, might have been facilitated by ocean current variations.


Asunto(s)
Tiburones , Animales , Biodiversidad , Brasil , Especies en Peligro de Extinción , Alimentos Marinos
14.
Nat Chem Biol ; 18(1): 56-63, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34782742

RESUMEN

Nuclear receptor-binding SET domain-containing 2 (NSD2) is the primary enzyme responsible for the dimethylation of lysine 36 of histone 3 (H3K36), a mark associated with active gene transcription and intergenic DNA methylation. In addition to a methyltransferase domain, NSD2 harbors two proline-tryptophan-tryptophan-proline (PWWP) domains and five plant homeodomains (PHDs) believed to serve as chromatin reading modules. Here, we report a chemical probe targeting the N-terminal PWWP (PWWP1) domain of NSD2. UNC6934 occupies the canonical H3K36me2-binding pocket of PWWP1, antagonizes PWWP1 interaction with nucleosomal H3K36me2 and selectively engages endogenous NSD2 in cells. UNC6934 induces accumulation of endogenous NSD2 in the nucleolus, phenocopying the localization defects of NSD2 protein isoforms lacking PWWP1 that result from translocations prevalent in multiple myeloma (MM). Mutations of other NSD2 chromatin reader domains also increase NSD2 nucleolar localization and enhance the effect of UNC6934. This chemical probe and the accompanying negative control UNC7145 will be useful tools in defining NSD2 biology.


Asunto(s)
Nucléolo Celular/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Sondas Moleculares/química , Dominios Proteicos , Proteínas Represoras/metabolismo , Metilación , Mieloma Múltiple/metabolismo , Nucleosomas/metabolismo
15.
J Biochem Mol Toxicol ; 35(10): e22877, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34382705

RESUMEN

Mygalin, a diacylspermidine that is naturally found in the hemolymph of the spider Acanthoscurria gomesiana, is of interest for development as a potential analgesic. Previous studies have shown that acylpolyamines modulate glutamatergic receptors with the potential to alter pain pathways. This study aimed to evaluate the effects of mygalin on acute and chronic pain in rodents. For evaluation of acute pain, Wistar rats were subjected to tail-flick and hot-plate nociceptive tests. For the evaluation of chronic neuropathic pain, a partial ligation of the sciatic nerve was performed and, 21 days later, animals were examined in hot-plate, tail-flick, acetone, and von Frey tests. Either Mygalin or vehicle was microinjected in the dorsal raphe nucleus (DRN) before the tests. Another group was pretreated with selective antagonists of glutamate receptors (LY 235959, MK-801, CNQX, and NBQX). Mygalin decreases nociceptive thresholds on both acute and chronic neuropathic pain models in all the tests performed. The lowest dose of mygalin yielded the most effective nociception, showing an increase of 63% of the nociceptive threshold of animals with neuropathic chronic pain. In conclusion, mygalin microinjection in the DRN results in antinociceptive effect in models of neuropathic pain, suggesting that acylpolyamines and their derivatives, such as this diacylspermidine, could be pursued for the treatment of neuropathic pain and development of selective analgesics.


Asunto(s)
Dolor Agudo/tratamiento farmacológico , Analgésicos/administración & dosificación , Dolor Crónico/tratamiento farmacológico , Núcleo Dorsal del Rafe/efectos de los fármacos , Neuralgia/tratamiento farmacológico , Espermidina/análogos & derivados , Arañas/metabolismo , Drogas Sintéticas/administración & dosificación , Animales , Modelos Animales de Enfermedad , Hemolinfa/química , Masculino , Microinyecciones/métodos , Ratas , Ratas Wistar , Espermidina/administración & dosificación , Resultado del Tratamiento
16.
Behav Brain Res ; 415: 113522, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34391797

RESUMEN

BACKGROUND: Motor cortex stimulation (MCS) is proper as a non-pharmacological therapy for patients with chronic and neuropathic pain (NP). AIMS: This work aims to investigate if the MCS in the primary motor cortex (M1) produces analgesia and how the MCS could interfere in the MCS-induced analgesia. Also, to elucidate if the persistent activation of N-methyl-d-aspartic acid receptor (NMDAr) in the periaqueductal grey matter (PAG) can contribute to central sensitisation of the NP. METHODS: Male Wistar rats were submitted to the von Frey test to evaluate the mechanical allodynia after 21 days of chronic constriction injury (CCI) of the sciatic nerve. The MCS was performed with low-frequency (20 µA, 100 Hz) currents during 15 s by a deep brain stimulation (DBS) device. Moreover, the effect of M1-treatment with an NMDAr agonist (at 2, 4, and 8 nmol) was investigated in CCI rats. The PAG dorsomedial column (dmPAG) was pretreated with the NMDAr antagonist LY 235959 (at 8 nmol), followed by MCS. RESULTS: The MCS decreased the mechanical allodynia in rats with chronic NP. The M1-treatment with an NMDA agonist at 2 and 8 nmol reduced the mechanical allodynia in CCI rats. In addition, dmPAG-pretreatment with LY 235959 at 8 nmol attenuated the mechanical allodynia evoked by MCS. CONCLUSION: The M1 cortex glutamatergic system is involved in the modulation of chronic NP. The analgesic effect of MCS may depend on glutamate signaling recruitting NMDAr located on PAG neurons in rodents with chronic NP.


Asunto(s)
Dolor Crónico/terapia , Estimulación Encefálica Profunda , Agonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Corteza Motora/efectos de los fármacos , Neuralgia/terapia , Sustancia Gris Periacueductal/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/fisiología , Analgesia , Animales , Modelos Animales de Enfermedad , Isoquinolinas/farmacología , Masculino , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores
17.
J Med Chem ; 64(3): 1584-1592, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-33522809

RESUMEN

Increased activity of the lysine methyltransferase NSD2 driven by translocation and activating mutations is associated with multiple myeloma and acute lymphoblastic leukemia, but no NSD2-targeting chemical probe has been reported to date. Here, we present the first antagonists that block the protein-protein interaction between the N-terminal PWWP domain of NSD2 and H3K36me2. Using virtual screening and experimental validation, we identified the small-molecule antagonist 3f, which binds to the NSD2-PWWP1 domain with a Kd of 3.4 µM and abrogates histone H3K36me2 binding to the PWWP1 domain in cells. This study establishes an alternative approach to targeting NSD2 and provides a small-molecule antagonist that can be further optimized into a chemical probe to better understand the cellular function of this protein.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , N-Metiltransferasa de Histona-Lisina/antagonistas & inhibidores , Proteínas Represoras/antagonistas & inhibidores , Simulación por Computador , Cristalografía por Rayos X , Descubrimiento de Drogas/métodos , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , N-Metiltransferasa de Histona-Lisina/efectos de los fármacos , Humanos , Ligandos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Dominios Proteicos , Proteínas Represoras/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas , Relación Estructura-Actividad
18.
Pain Med ; 22(2): 338-351, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-32875331

RESUMEN

BACKGROUND: Chronic constriction injury (CCI) is a model of neuropathic pain induced by four loose ligatures around the sciatic nerve. This work aimed to investigate the sensory, affective, cognitive, and motor changes induced by an adaptation of the CCI model by applying a single ligature around the sciatic nerve. METHODS: Mechanical allodynia was measured from day 1 to day 28 postsurgery by the von Frey test. The beam walking test (BWT) was conducted weekly until 28 days after surgery. Anxiety- and depression-like behaviors, and cognitive performance were assessed through the open field (OF), forced swimming (FS), and novel object recognition (NOR) tests, respectively, 21 days after surgery. RESULTS: The two CCI models, both Bennett and Xie's model (four ligatures of the sciatic nerve) and a modification of it (one ligature), induced mechanical allodynia, increased immobility in the FS, and reduced recognition index in the NOR. The exploratory behavior and time spent in the central part of the arena decreased, while the defensive behavior increased in the OF. The animals subjected to the two CCI models showed motor alterations in the BWT; however, autotomy was observed only in the group with four ligatures and not in the group with a single ligature. CONCLUSIONS: Overall these results demonstrate that our adapted CCI model, using a single ligature around the sciatic nerve, induces sensory, affective, cognitive, and motor alterations comparable to the CCI model with four ligatures without generating autotomy. This adaptation to the CCI model may therefore represent an appropriate and more easily performed model for inducing neuropathic pain and study underlying mechanisms and effective treatments.


Asunto(s)
Disfunción Cognitiva , Mononeuropatías , Neuralgia , Animales , Constricción , Modelos Animales de Enfermedad , Hiperalgesia/epidemiología , Neuralgia/epidemiología , Neuralgia/etiología , Ratas , Nervio Ciático
19.
Brain Res Bull ; 165: 118-128, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33038420

RESUMEN

Neuropathic pain (NP) is a challenge due to our limited understanding of the mechanisms that initiate and maintain chronic pain. The prelimbic division (PrL) of the medial prefrontal cortex (mPFC) is an important area of the emotional and cognitive components of pain and pharmacological systems can interact into the neocortex to elaborate the chronic pain. This work aimed to investigate the pharmacological cross-talk between synaptic neurotransmission, neuroanatomical approaches and NP conditions. A bidirectional neural tract tracer, the 3000-molecular-weight biodextran (BDA) was microinjected into the PrL cortex. The mechanical withdrawal threshold (MWT) was recorded by a von Frey test, and the effect of prelimbic cortex CB1, NMDA, and TRPV1 receptor modulation was evaluated 21 days after chronic constriction injury (CCI) of the sciatic nerve in male Wistar rats. Microinjection of a bidirectional neurotracer in the PrL cortex showed connections with the lateral division of the mediodorsal thalamic nucleus (MDL), central division of the mediodorsal thalamic nucleus (MDC), centrolateral thalamic nucleus (CL), ventromedial thalamic nucleus (VM), and the paracentral thalamic nucleus (PC). In detail, AM251, a CB1 receptor antagonist (at 50, 100 and 200 pmol) microinjections intra-PrL cortex decreased the MWT. Administrations of 6-iodonordihydrocapsaicin (6-I-CPS), a transient receptor potential vanilloid type 1 (TRPV1) antagonist, at 3 nmol and the endocannabinoid anandamide (AEA) at 50 and 100 pmol increased the MWT. AEA at 200 pmol injected in the PrL cortex decreased the MWT, and this hyperalgesic effect was blocked by 6-I-CPS at 3 nmol. The AEA (at 100 pmol) anti-allodynic effect was attenuated by AM251 (at 5 pmol). The TRPV1 selective agonist N-oleoyldopamine (OLDA) at 10 µM decreased the MWT. The blockade of the NMDA receptor with LY235959 (at 8 nmol) and 6-I-CPS (at 3 nmol) reversed the OLDA (at 10 µM) hyperalgesic effect. These findings showed that the PrL cortex sends pathways to thalamic nuclei that can mediate the nociception. We also suggest that the PrL cortex is involved in the potentiation and maintenance of mechanical allodynia by NMDA and TRPV1 receptor activation and that attenuation of this allodynia depends on CB1 receptor activation during NP.


Asunto(s)
Corteza Cerebral/metabolismo , Neuralgia/metabolismo , Receptor Cannabinoide CB1/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Canales Catiónicos TRPV/metabolismo , Animales , Antagonistas de Receptores de Cannabinoides/farmacología , Capsaicina/análogos & derivados , Capsaicina/farmacología , Corteza Cerebral/efectos de los fármacos , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores/farmacología , Masculino , Ratas , Ratas Wistar
20.
Sci Adv ; 6(20): eaay3514, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32440540

RESUMEN

The degradation of cadmium sulfide (CdS)-based oil paints is a phenomenon potentially threatening the iconic painting The Scream (ca. 1910) by Edvard Munch (Munch Museum, Oslo) that is still poorly understood. Here, we provide evidence for the presence of cadmium sulfate and sulfites as alteration products of the original CdS-based paint and explore the external circumstances and internal factors causing this transformation. Macroscale in situ noninvasive spectroscopy studies of the painting in combination with synchrotron-radiation x-ray microspectroscopy investigations of a microsample and artificially aged mock-ups show that moisture and mobile chlorine compounds are key factors for promoting the oxidation of CdS, while light (photodegradation) plays a less important role. Furthermore, under exposure to humidity, parallel/secondary reactions involving dissolution, migration through the paint, and recrystallization of water-soluble phases of the paint are associated with the formation of cadmium sulfates.

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