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1.
Front Cardiovasc Med ; 11: 1400637, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38845686

RESUMO

Objective: To evaluate incidence and predictors of early silent bypass occlusion following coronary bypass surgery using cardiac computed tomography angiography. Methods: A total of 439 consecutive patients with mean age of 66 ± 10 years comprising 17% (n = 75) females underwent isolated coronary bypass surgery followed by CT scan before discharge. Graft patency was evaluated in 1,319 anastomoses where 44% (n = 580) arterial and 56% (n = 739) vein graft anastomosis were performed. Cardiovascular risk factors, demographics, and intraoperative variables were analyzed. We conducted univariable and multivariable logistic regression analyses to analyze variables potentially associated with graft occlusion following CABG. Variables included gender, surgery duration, graft flow, pulsatility index, vein vs. artery graft, and recent MI. Results: Overall incidence of graft occlusion was 2.4% (31/1,319), and it was diagnosed in 6.6% (29/439) of patients. The difference in occlusion between arterial (2.1%) and vein (2.6%) grafts was not significant, p = 0.68. The duration of intervention p = 0.034, cross clamp time p = 0.024 as well the number of distal anastomosis p = 0.034 were significantly higher in occlusion group. The univariate and multivariate logistic regression indicated duration of surgery being predictive for bypass graft occlusion with OR = 1.18; 95% CI: 1.01-1.38; p = 0.035. Conclusions: Early graft occlusion was associated with surgical factors. The number of distant anastamoses, along duration of surgical intervention were, significantly influenced the risk of EGO. Prolonged procedural time reflecting complex coronary pathology and time-consuming revascularization procedure was as well associated to the elevated risk of occlusion.

2.
ACS Appl Electron Mater ; 6(5): 2909-2916, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38828039

RESUMO

Conjugated polymers with oligoether side chains make up a promising class of thermoelectric materials. In this work, the impact of the side-chain length on the thermoelectric and mechanical properties of polythiophenes is investigated. Polymers with tri-, tetra-, or hexaethylene glycol side chains are compared, and the shortest length is found to result in thin films with the highest degree of order upon doping with the p-dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). As a result, a stiff material with an electrical conductivity of up to 830 ± 15 S cm-1 is obtained, resulting in a thermoelectric power factor of about 21 µW m-1 K-2 in the case of as-cast films. Aging at ambient conditions results in an initial decrease in thermoelectric properties but then yields a highly stable performance for at least 3 months, with values of about 200 S cm-1 and 5 µW m-1 K-2. Evidently, identification of the optimal side-chain length is an important criterion for the design of conjugated polymers for organic thermoelectrics.

3.
Nucleic Acids Res ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752495

RESUMO

Chromatin, the nucleoprotein complex consisting of DNA and histone proteins, plays a crucial role in regulating gene expression by controlling access to DNA. Chromatin modifications are key players in this regulation, as they help to orchestrate DNA transcription, replication, and repair. These modifications recruit epigenetic 'reader' proteins, which mediate downstream events. Most modifications occur in distinctive combinations within a nucleosome, suggesting that epigenetic information can be encoded in combinatorial chromatin modifications. A detailed understanding of how multiple modifications cooperate in recruiting such proteins has, however, remained largely elusive. Here, we integrate nucleosome affinity purification data with high-throughput quantitative proteomics and hierarchical interaction modeling to estimate combinatorial effects of chromatin modifications on protein recruitment. This is facilitated by the computational workflow asteRIa which combines hierarchical interaction modeling, stability-based model selection, and replicate-consistency checks for a stable estimation of Robust Interactions among chromatin modifications. asteRIa identifies several epigenetic reader candidates responding to specific interactions between chromatin modifications. For the polycomb protein CBX8, we independently validate our results using genome-wide ChIP-Seq and bisulphite sequencing datasets. We provide the first quantitative framework for identifying cooperative effects of chromatin modifications on protein binding.

4.
Chem Sci ; 15(20): 7679-7688, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38784738

RESUMO

Through direct arylation polymerization, a series of mixed ion-electron conducting polymers with a low synthetic complexity index is synthesized. A thieno[3,2-b]thiophene monomer with oligoether side chains is used in direct arylation polymerization together with a wide range of aryl bromides with varying electronic character from electron-donating thiophene to electron-accepting benzothiadiazole. The obtained polymers are less synthetically complex than other mixed ion-electron conducting polymers due to higher yield, fewer synthetic steps and less toxic reagents. Organic electrochemical transistors (OECTs) based on a newly synthesized copolymer comprising thieno[3,2-b]thiophene with oligoether side chains and bithiophene exhibit excellent device performance. A high charge-carrier mobility of up to µ = 1.8 cm2 V-1 s-1 was observed, obtained by dividing the figure of merit [µC*] from OECT measurements by the volumetric capacitance C* from electrochemical impedance spectroscopy, which reached a value of more than 215 F cm-3.

5.
J Biomed Sci ; 31(1): 56, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807208

RESUMO

BACKGROUND: Infections with Herpes simplex virus (HSV)-1 or -2 usually present as mild chronic recurrent disease, however in rare cases can result in life-threatening conditions with a large spectrum of pathology. Monoclonal antibody therapy has great potential especially to treat infections with virus resistant to standard therapies. HDIT101, a humanized IgG targeting HSV-1/2 gB was previously investigated in phase 2 clinical trials. The aim of this study was to develop a next-generation therapy by combining different antiviral monoclonal antibodies. METHODS: A lymph-node derived phage display library (LYNDAL) was screened against recombinant gB from Herpes simplex virus (HSV) -1 and HDIT102 scFv was selected for its binding characteristics using bio-layer interferometry. HDIT102 was further developed as fully human IgG and tested alone or in combination with HDIT101, a clinically tested humanized anti-HSV IgG, in vitro and in vivo. T-cell stimulating activities by antigen-presenting cells treated with IgG-HSV immune complexes were analyzed using primary human cells. To determine the epitopes, the cryo-EM structures of HDIT101 or HDIT102 Fab bound to HSV-1F as well as HSV-2G gB protein were solved at resolutions < 3.5 Å. RESULTS: HDIT102 Fab showed strong binding to HSV-1F gB with Kd of 8.95 × 10-11 M and to HSV-2G gB with Kd of 3.29 × 10-11 M. Neutralization of cell-free virus and inhibition of cell-to-cell spread were comparable between HDIT101 and HDIT102. Both antibodies induced internalization of gB from the cell surface into acidic endosomes by binding distinct epitopes in domain I of gB and compete for binding. CryoEM analyses revealed the ability to form heterogenic immune complexes consisting of two HDIT102 and one HDIT101 Fab bound to one gB trimeric molecule. Both antibodies mediated antibody-dependent phagocytosis by antigen presenting cells which stimulated autologous T-cell activation. In vivo, the combination of HDIT101 and HDIT102 demonstrated synergistic effects on survival and clinical outcome in immunocompetent BALB/cOlaHsd mice. CONCLUSION: This biochemical and immunological study showcases the potential of an effective combination therapy with two monoclonal anti-gB IgGs for the treatment of HSV-1/2 induced disease conditions.


Assuntos
Herpes Simples , Humanos , Animais , Camundongos , Herpes Simples/imunologia , Herpes Simples/terapia , Herpes Simples/tratamento farmacológico , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Antivirais/imunologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Feminino , Herpesvirus Humano 2/imunologia , Herpesvirus Humano 2/efeitos dos fármacos
6.
Chem Sci ; 15(15): 5496-5506, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38638216

RESUMO

Tetrapyridyl-functionalized phosphinines were prepared and structurally characterized. The donor-functionalized aromatic phosphorus heterocycles react highly selectively and even reversibly with water. Calculations reveal P,N-cooperativity for this process, with the flanking pyridyl groups serving to kinetically enhance the formal oxidative addition process of H2O to the low-coordinate phosphorus atom via H-bonding. Subsequent tautomerization forms 1,2-dihydrophosphinine derivatives, which can be quantitatively converted back to the phosphinine by applying vacuum, even at room temperature. This process can be repeated numerous times, without any sign of decomposition of the phosphinine. In the presence of CuI·SMe2, dimeric species of the type ([Cu2I2(phosphinine)]2) are formed, in which each phosphorus atom shows the less common µ2-bridging 2e--lone-pair-donation to two Cu(i)-centres. Our results demonstrate that fully unsaturated phosphorus heterocycles, containing reactive P[double bond, length as m-dash]C double bonds, are interesting candidates for the activation of E-H bonds, while the aromaticity of such compounds plays an appreciable role in the reversibility of the reaction, supported by NICS calculations.

7.
Orthop Rev (Pavia) ; 16: 116370, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666190

RESUMO

Background Following surgical treatment of ankle fractures, geriatric patients face high complication rates (CR) in literature. Commonly used diagnostic and treatment algorithms fail to consider requirements of ageing patients which increases the risk of postoperative complications. Objective Present study critically evaluated surgical management of ankle fractures in patients over 65 years old, with focus on identifying modifiable risk factors and effective comorbidity management strategies. Methods We conducted a retrospective single-center study on patients who underwent surgical treatment of an ankle fracture. Based on their age, participants were divided into non-geriatric patients (NGP<65y) and geriatric patients (GP≥65y). We analyzed overall CR and number of minor and major complications in relation to timing of surgery, biological sex, injury pattern, osteosynthesis, pre-existing medical conditions, and postoperative care. Results 402 patients were included. GP encountered significantly higher overall (p<0.001), minor (p<0.001) and major (p=0.003) complications. They presented more complex, displaced and open fractures. Predominant factor contributing to higher CR in NGP and markedly in GP was concomitant diseases, presenting a strong OR of 19,290 (p<0.001) and 17,022 (p<0.001). Delaying surgery and managing comorbidities preoperatively had a favorable impact. Conclusion We revealed a high significant correlation between pre-existing medical conditions and postoperative results. To ascertain viability of delayed surgery in facilitating additional diagnostics and treatment of comorbidities, further comparative trials with a larger cohort are imperative.

9.
Adv Mater ; : e2313508, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607958

RESUMO

The most common type of insulation of extruded high-voltage power cables is composed of low-density polyethylene (LDPE), which must be crosslinked to adjust its thermomechanical properties. A major drawback is the need for hazardous curing agents and the release of harmful curing byproducts during cable production, while the thermoset nature complicates reprocessing of the insulation material. This perspective explores recent progress in the development of alternative concepts that allow to avoid byproducts through either click chemistry type curing of polyethylene-based copolymers or the use of polyolefin blends or copolymers, which entirely removes the need for crosslinking. Moreover, polypropylene-based thermoplastic formulations enable the design of insulation materials that can withstand higher cable operating temperatures and facilitate reprocessing by remelting once the cable reaches the end of its lifetime. Finally, polyethylene-based covalent and non-covalent adaptable networks are explored, which may allow to combine the advantages of thermoset and thermoplastic insulation materials in terms of thermomechanical properties and reprocessability.

10.
Eur Heart J ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592444

RESUMO

BACKGROUND AND AIMS: Patients with atrial fibrillation (AF) are at increased risks of cardiovascular diseases and mortality, but risks according to age at diagnosis have not been reported. This study investigated age-specific risks of outcomes among patients with AF and the background population. METHODS: This nationwide population-based cohort study included patients with AF and controls without outcomes by the application of exposure density matching on the basis of sex, year of birth, and index date. The absolute risks and hazard rates were stratified by age groups and assessed using competing risk survival analyses and Cox regression models, respectively. The expected differences in residual life years among participants were estimated. RESULTS: The study included 216 579 AF patients from year 2000 to 2020 and 866 316 controls. The mean follow-up time was 7.9 years. Comparing AF patients with matched controls, the hazard ratios among individuals ≤50 years was 8.90 [95% confidence interval (CI), 7.17-11.0] for cardiomyopathy, 8.64 (95% CI, 7.74-9.64) for heart failure, 2.18 (95% CI, 1.89-2.52) for ischaemic stroke, and 2.74 (95% CI, 2.53-2.96) for mortality. The expected average loss of life years among individuals ≤50 years was 9.2 years (95% CI, 9.0-9.3) years. The estimates decreased with older age. CONCLUSIONS: The findings show that earlier diagnosis of AF is associated with a higher hazard ratio of subsequent myocardial disease and shorter life expectancy. Further studies are needed to determine causality and whether AF could be used as a risk marker among particularly younger patients.

12.
Chemistry ; : e202400592, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597259

RESUMO

Triazaphospholes are potential polydentate ligands due to the presence of both phosphorus and nitrogen donor atoms within the aromatic 5-membered heterocycle. The incorporation of an additional pyridyl-substituent opens up the possibility of a post-synthesis modification via chemoselective and also stepwise alkylation exclusively of the nitrogen atoms. This can be controlled by the choice and by the stoichiometry of the electrophile and allows the targeted synthesis of a variety of novel mono- and dicationic ligands. Reaction with Cu(I)-halides causes the formation of cuprates of the type [CuXn](n-1)-, which enables coordination of the π-acidic phosphorus donor to the negatively charged metal core, which is favored over the coordination by a strongly σ-donating nitrogen atom. The use of cationic triazaphosphole derivatives can be used as a strategy to enforce the coordination of the ligand to an electron rich metal solely via the phosphorus atom. However, there is a subtle balance between the formation of either coordination polymers or dimeric structures, as the substitution pattern on the heterocycle and the nature of the halide have a large influence on the coordination motifs formed.

13.
Resuscitation ; 198: 110197, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582441

RESUMO

BACKGROUND: There has been no previous thorough toxicological examination of a cohort of patients with resuscitated sudden cardiac arrest. We aimed to determine the qualitative and quantitative drug composition in a resuscitated sudden cardiac arrest population, using forensic toxicology, with focus on prescribed, non-prescribed, and commonly abused drugs. METHODS: Individuals aged 18-90 years with resuscitated sudden cardiac arrest of presumed cardiac causes were prospectively included from a single tertiary center. Data from the sudden cardiac arrest hospitalization was collected from medical reports. Drugs used during resuscitation or before the blood sampling were identified and excluded in each patient. Mass spectrometry-based toxicology was performed to determine the absence or presence of most drugs and to quantify the findings. RESULTS: Among 186 consecutively enrolled resuscitated sudden cardiac arrest patients (median age 62 years, 83% male), 90% had a shockable rhythm, and were primarily caused by ischemic heart disease (66%). In total, 90 different drugs (excluding metabolites) were identified, and 82% of patients had at least one drug detected (median of 2 detected drugs (IQR:1-4)) (polypharmacy). Commonly abused drugs were present in 16%, and QT-prolonging drugs were present in 12%. Polypharmacy (≥5drugs) were found in 19% of patients. Importantly, none had potentially lethal concentrations of any drugs. CONCLUSION: In resuscitated sudden cardiac arrest patients with cardiac arrest of presumed cardiac cause, routine toxicological screening provides limited extra information. However, the role of polypharmacy in sudden cardiac arrest requires further investigation. No occult overdose-related cardiac arrests were identified.


Assuntos
Morte Súbita Cardíaca , Centros de Atenção Terciária , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Adulto , Centros de Atenção Terciária/estatística & dados numéricos , Estudos Prospectivos , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/epidemiologia , Idoso de 80 Anos ou mais , Adolescente , Espectrometria de Massas/métodos , Adulto Jovem , Reanimação Cardiopulmonar/métodos , Sobreviventes/estatística & dados numéricos
14.
Neuropharmacology ; 253: 109948, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38636728

RESUMO

Alcohol consumption is a widespread phenomenon throughout the world. However, how recreational alcohol use evolves into alcohol use disorder (AUD) remains poorly understood. The Smpd3 gene and its coded protein neutral sphingomyelinase (NSM) are associated with alcohol consumption in humans and alcohol-related behaviors in mice, suggesting a potential role in this transition. Using multiparametric magnetic resonance imaging, we characterized the role of NSM in acute and chronic effects of alcohol on brain anatomy and function in female mice. Chronic voluntary alcohol consumption (16 vol% for at least 6 days) affected brain anatomy in WT mice, reducing regional structure volume predominantly in cortical regions. Attenuated NSM activity prevented these anatomical changes. Functional MRI linked these anatomical adaptations to functional changes: Chronic alcohol consumption in mice significantly modulated resting state functional connectivity (RS FC) in response to an acute ethanol challenge (i.p. bolus of 2 g kg-1) in heterozygous NSM knockout (Fro), but not in WT mice. Acute ethanol administration in alcohol-naïve WT mice significantly decreased RS FC in cortical and brainstem regions, a key finding that was amplified in Fro mice. Regarding direct pharmacological effects, acute ethanol administration increased the regional cerebral blood volume (rCBV) in many brain areas. Here, chronic alcohol consumption otherwise attenuated the acute rCBV response in WT mice but enhanced it in Fro mice. Altogether, these findings suggest a differential role for NSM in acute and chronic functional brain responses to alcohol. Therefore, targeting NSM may be useful in the prevention or treatment of AUD.


Assuntos
Encéfalo , Etanol , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Esfingomielina Fosfodiesterase , Animais , Esfingomielina Fosfodiesterase/metabolismo , Esfingomielina Fosfodiesterase/genética , Feminino , Encéfalo/efeitos dos fármacos , Etanol/farmacologia , Etanol/administração & dosagem , Camundongos , Consumo de Bebidas Alcoólicas , Depressores do Sistema Nervoso Central/farmacologia , Alcoolismo
15.
ACS Chem Neurosci ; 15(7): 1298-1320, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38499042

RESUMO

Serotonin (5-HT) is a vital modulatory neurotransmitter responsible for regulating most behaviors in the brain. An inefficient 5-HT synaptic function is often linked to various mental disorders. Primarily, membrane proteins controlling the expression and activity of 5-HT synthesis, storage, release, receptor activation, and inactivation are critical to 5-HT signaling in synaptic and extra-synaptic sites. Moreover, these signals represent information transmission across membranes. Although the lipid membrane environment is often viewed as fairly stable, emerging research suggests significant functional lipid-protein interactions with many synaptic 5-HT proteins. These protein-lipid interactions extend to almost all the primary lipid classes that form the plasma membrane. Collectively, these lipid classes and lipid-protein interactions affect 5-HT synaptic efficacy at the synapse. The highly dynamic lipid composition of synaptic membranes suggests that these lipids and their interactions with proteins may contribute to the plasticity of the 5-HT synapse. Therefore, this broader protein-lipid model of the 5-HT synapse necessitates a reconsideration of 5-HT's role in various associated mental disorders.


Assuntos
Serotonina , Transdução de Sinais , Humanos , Serotonina/metabolismo , Sinapses/metabolismo , Membrana Celular/metabolismo , Lipídeos , Transmissão Sináptica/fisiologia
16.
Nature ; 627(8004): 671-679, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448585

RESUMO

DNA and histone modifications combine into characteristic patterns that demarcate functional regions of the genome1,2. While many 'readers' of individual modifications have been described3-5, how chromatin states comprising composite modification signatures, histone variants and internucleosomal linker DNA are interpreted is a major open question. Here we use a multidimensional proteomics strategy to systematically examine the interaction of around 2,000 nuclear proteins with over 80 modified dinucleosomes representing promoter, enhancer and heterochromatin states. By deconvoluting complex nucleosome-binding profiles into networks of co-regulated proteins and distinct nucleosomal features driving protein recruitment or exclusion, we show comprehensively how chromatin states are decoded by chromatin readers. We find highly distinctive binding responses to different features, many factors that recognize multiple features, and that nucleosomal modifications and linker DNA operate largely independently in regulating protein binding to chromatin. Our online resource, the Modification Atlas of Regulation by Chromatin States (MARCS), provides in-depth analysis tools to engage with our results and advance the discovery of fundamental principles of genome regulation by chromatin states.


Assuntos
Montagem e Desmontagem da Cromatina , Cromatina , Proteínas Nucleares , Nucleossomos , Proteômica , Humanos , Sítios de Ligação , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , DNA/genética , DNA/metabolismo , Elementos Facilitadores Genéticos , Heterocromatina/genética , Heterocromatina/metabolismo , Histonas/metabolismo , Proteínas Nucleares/análise , Proteínas Nucleares/metabolismo , Nucleossomos/química , Nucleossomos/genética , Nucleossomos/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteômica/métodos
17.
Hypertension ; 81(5): 1156-1166, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38445514

RESUMO

BACKGROUND: Hypertension, a complex condition, is primarily defined based on blood pressure readings without involving its pathophysiological mechanisms. We aimed to identify biomarkers through a proteomic approach, thereby enhancing the future definition of hypertension with insights into its molecular mechanisms. METHODS: The discovery analysis included 1560 participants, aged 55 to 74 years at baseline, from the KORA (Cooperative Health Research in the Region of Augsburg) S4/F4/FF4 cohort study, with 3332 observations over a median of 13.4 years of follow-up. Generalized estimating equations were used to estimate the associations of 233 plasma proteins with hypertension and systolic blood pressure (SBP). For validation, proteins significantly associated with hypertension or SBP in the discovery analysis were validated in the KORA Age1/Age2 cohort study (1024 participants, 1810 observations). A 2-sample Mendelian randomization analysis was conducted to infer causalities of validated proteins with SBP. RESULTS: Discovery analysis identified 49 proteins associated with hypertension and 99 associated with SBP. Validation in the KORA Age1/Age2 study replicated 7 proteins associated with hypertension and 23 associated with SBP. Three proteins, NT-proBNP (N-terminal pro-B-type natriuretic peptide), KIM1 (kidney injury molecule 1), and OPG (osteoprotegerin), consistently showed positive associations with both outcomes. Five proteins demonstrated potential causal associations with SBP in Mendelian randomization analysis, including NT-proBNP and OPG. CONCLUSIONS: We identified and validated 7 hypertension-associated and 23 SBP-associated proteins across 2 cohort studies. KIM1, NT-proBNP, and OPG demonstrated robust associations, and OPG was identified for the first time as associated with blood pressure. For NT-proBNP (protective) and OPG, causal associations with SBP were suggested.


Assuntos
Hipertensão , Proteômica , Humanos , Pressão Sanguínea/fisiologia , Estudos de Coortes , Biomarcadores , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos
19.
Br J Pharmacol ; 181(13): 2070-2084, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38523471

RESUMO

BACKGROUND AND PURPOSE: Kratom is a preparation from Mitragyna speciosa, which is used as a natural drug preparation for many purposes around the world. However, an overdose of Kratom may cause addiction-like problems including aversive withdrawal states resulting in cognitive impairments via unknown mechanisms. Its main psychoactive alkaloid is mitragynine, showing opioid-like properties. EXPERIMENTAL APPROACH: Here, we analysed the neuropharmacological effects of mitragynine compared with morphine withdrawal in rats and searched for a pharmacological treatment option that may reverse the occurring cognitive deficits that usually aggravate withdrawal. KEY RESULTS: We found that withdrawal from 14-day mitragynine (1-10 mg·kg-1·day-1) treatment caused dose-dependent behavioural withdrawal signs resembling those of morphine (5 mg·kg-1·day-1) withdrawal. However, mitragynine (5 and 10 mg·kg-1·day-1) withdrawal also induced impairments in a passive avoidance task. Mitragynine withdrawal not only reduced hippocampal field excitatory postsynaptic potential (fEPSP) amplitudes in basal synaptic transmission and long-term potentiation (LTP) but also reduced epigenetic markers, such as histone H3K9 and H4K12 expression. At the same time, it up-regulates HDAC2 expression. Targeting the epigenetic adaptations with the HDAC inhibitor, SAHA, reversed the effects of mitragynine withdrawal on epigenetic dysregulation, hippocampal input/output curves, paired-pulse facilitation, LTP and attenuated the cognitive deficit. However, SAHA amplified the effects of morphine withdrawal. CONCLUSION AND IMPLICATIONS: The data from this work show that changes in histone expression and downstream hippocampal plasticity may explain mitragynine, but not morphine, withdrawal behaviours and cognitive impairments. Thus, it may provide a new treatment approach for aversive Kratom/mitragynine withdrawal and addiction.


Assuntos
Disfunção Cognitiva , Epigênese Genética , Alcaloides de Triptamina e Secologanina , Síndrome de Abstinência a Substâncias , Animais , Alcaloides de Triptamina e Secologanina/farmacologia , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Masculino , Ratos , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/induzido quimicamente , Ratos Sprague-Dawley , Morfina/farmacologia , Mitragyna/química , Comportamento Animal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Aprendizagem da Esquiva/efeitos dos fármacos , Relação Dose-Resposta a Droga
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