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1.
bioRxiv ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38854101

RESUMO

The G2019S mutation in the leucine-rich repeat kinase 2 (LRRK2) gene is a major risk factor for the development of Parkinson's disease (PD). LRRK2, although ubiquitously expressed, is highly abundant in cells of the innate immune system. Given the importance of central and peripheral immune cells in the development of PD, we sought to investigate the consequences of the G2019S mutation on microglial and monocyte transcriptome and function. We have generated large-scale transcriptomic profiles of isogenic human induced microglial cells (iMGLs) and patient derived monocytes carrying the G2019S mutation under baseline culture conditions and following exposure to the proinflammatory factors IFNγ and LPS. We demonstrate that the G2019S mutation exerts a profound impact on the transcriptomic profile of these myeloid cells, and describe corresponding functional differences in iMGLs. The G2019S mutation led to an upregulation in lipid metabolism and phagolysosomal pathway genes in untreated and LPS/IFNγ stimulated iMGLs, which was accompanied by an increased phagocytic capacity of myelin debris. We also identified dysregulation of cell cycle genes, with a downregulation of the E2F4 regulon. Transcriptomic characterization of human-derived monocytes carrying the G2019S mutation confirmed alteration in lipid metabolism associated genes. Altogether, these findings reveal the influence of G2019S on the dysregulation of the myeloid cell transcriptome under proinflammatory conditions.

2.
Chem Commun (Camb) ; 60(45): 5808-5811, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38712454

RESUMO

Metal-organic frameworks (MOFs) have shown promise for adsorptive separations of metal ions. Herein, MOFs based on highly stable Zr(IV) building units were systematically functionalized with targeted metal binding groups. Through competitive adsorption studies, it was shown that the selectivity for different metal ions was directly tunable through functional group chemistry.

3.
Plants (Basel) ; 13(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38592906

RESUMO

Olive anthracnose is the most important fungal disease of the olive fruit worldwide, with the fungus Colletotrichum acutatum as the main cause of the disease in Greece. A total of 11 commercial biological plant protection products (bioPPPs) (Amylo-X®, Botector®, FytoSave®, LBG 01F34®, Mevalone®, Polyversum®, Remedier®, Serenade® ASO, Sonata®, Trianum-P®, Vacciplant®), with various modes of action against the fungus C. acutatum, were evaluated by bioassays using detached fruits of two important olive Greek varieties, cv. Koroneiki and cv. Kalamon. Subsequently, the most effective bioPPPs were evaluated for their ability to induce plant defense mechanisms, by determining the expression levels of ten Olea europaea defense genes (Pal, CuaO, Aldh1, Bglu, Mpol, Lox, Phely, CHI-2, PR-10, PR-5). Remedier®, Trianum-P®, Serenade® ASO, Sonata®, and Mevalone® were the most effective in reducing disease severity, and/or inhibiting the conidia production by the fungus at high rates. Post bioPPPs application, high expression levels of several olive plant defense genes were observed. This study provides insights into commercial bioPPPs' effectiveness in controlling olive anthracnose, as well as biocontrol-agents-mediated modulation of olive defense mechanisms.

4.
Eur J Pharm Sci ; 197: 106776, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663759

RESUMO

The emergence of multidrug-resistant (MDR) strains causes severe problems in the treatment of microbial infections owing to limited treatment options. Antimicrobial peptides (AMPs) are drawing considerable attention as promising antibiotic alternative candidates to combat MDR bacterial and fungal infections. Herein, we present a series of small amphiphilic membrane-active cyclic peptides composed, in part, of various nongenetically encoded hydrophilic and hydrophobic amino acids. Notably, lead cyclic peptides 3b and 4b showed broad-spectrum activity against drug-resistant Gram-positive (MIC = 1.5-6.2 µg/mL) and Gram-negative (MIC = 12.5-25 µg/mL) bacteria, and fungi (MIC = 3.1-12.5 µg/mL). Furthermore, lead peptides displayed substantial antibiofilm action comparable to standard antibiotics. Hemolysis (HC50 = 230 µg/mL) and cytotoxicity (>70 % cell viability against four different mammalian cells at 100 µg/mL) assay results demonstrated the selective lethal action of 3b against microbes over mammalian cells. A calcein dye leakage experiment substantiated the membranolytic effect of 3b and 4b, which was further confirmed by scanning electron microscopy. The behavior of 3b and 4b in aqueous solution and interaction with phospholipid bilayers were assessed by employing nuclear magnetic resonance (NMR) spectroscopy in conjunction with molecular dynamics (MD) simulations, providing a solid structural basis for understanding their membranolytic action. Moreover, 3b exhibited stability in human blood plasma (t1/2 = 13 h) and demonstrated no signs of resistance development against antibiotic-resistant S. aureus and E. coli. These findings underscore the potential of these newly designed amphiphilic cyclic peptides as promising anti-infective agents, especially against Gram-positive bacteria.


Assuntos
Biofilmes , Farmacorresistência Bacteriana Múltipla , Hemólise , Testes de Sensibilidade Microbiana , Humanos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Antibacterianos/farmacologia , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Animais , Fungos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/química , Bactérias Gram-Negativas/efeitos dos fármacos
5.
Plants (Basel) ; 13(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38475414

RESUMO

The peach (Prunus persica L.) is one of the most important stone-fruit crops worldwide. Nevertheless, successful peach fruit production is seriously reduced by losses due to Monilinia fructicola the causal agent of brown rot. Chitosan has a broad spectrum of antimicrobial properties and may also act as an elicitor that activate defense responses in plants. As little is known about the elicitation potential of chitosan in peach fruits and its impact at their transcriptional-level profiles, the aim of this study was to uncover using RNA-seq the induced responses regulated by the action of chitosan in fruit-chitosan-M. fructicola interaction. Samples were obtained from fruits treated with chitosan or inoculated with M. fructicola, as well from fruits pre-treated with chitosan and thereafter inoculated with the fungus. Chitosan was found to delay the postharvest decay of fruits, and expression profiles showed that its defense-priming effects were mainly evident after the pathogen challenge, driven particularly by modulations of differentially expressed genes (DEGs) related to cell-wall modifications, pathogen perception, and signal transduction, preventing the spread of fungus. In contrast, as the compatible interaction of fruits with M. fructicola was challenged, a shift towards defense responses was triggered with a delay, which was insufficient to limit fungal expansion, whereas DEGs involved in particular processes have facilitated early pathogen colonization. Physiological indicators of peach fruits were also measured. Additionally, expression profiles of particular M. fructicola genes highlight the direct antimicrobial activity of chitosan against the fungus. Overall, the results clarify the possible mechanisms of chitosan-mediated tolerance to M. fructicola and set new foundations for the potential employment of chitosan in the control of brown rot in peaches.

8.
J Interferon Cytokine Res ; 44(3): 135-142, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38386538

RESUMO

Studying the levels of cytokines in the plasma of patients could be valuable in guiding immunotherapy policies. We assessed the plasma levels of 4 major cytokines [interferon (IFN)-ß, interleukin-2 (IL-2), tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-ß)] collected from 19 patients with ductal breast cancer (BCa), before surgery (BS) and 5 days after surgery (AS). The ratio AS/BS was also calculated and correlated with histopathological variables and tumor-infiltrating lymphocyte (TIL) density. The IFN-ß and TNF-α levels were significantly higher in BCa patients, BS and AS, than healthy controls (P < 0.02). High IL-2 levels BS were linked with node involvement (P = 0.02), and marginally with HER2 expression (P = 0.08), while high TNF-α levels were linked with high PgR expression (P = 0.02). Increasing IFN-ß, IL-2, and TNF-α levels were noted AS, which was more evident in patients with larger tumors. The TGF-ß levels were significantly lower in BCa patients (P < 0.007). Linear regression analysis showed a direct association of IFN-ß levels AS (P = 0.02, r = 0.52) and of TNF-α AS/BS-ratio (P = 0.001, r = 0.72) with TIL-density. It is suggested that although effector immune response is evident in the majority of early stage BCa patients, removal of the primary tumor further unblocks such responses.


Assuntos
Neoplasias da Mama , Citocinas , Humanos , Feminino , Interleucina-2 , Fator de Necrose Tumoral alfa , Neoplasias da Mama/cirurgia , Fator de Crescimento Transformador beta
9.
Int J Radiat Biol ; 100(5): 736-743, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38394349

RESUMO

INTRODUCTION: The role of the immune system in the efficacy of radiotherapy (RT) has been well established. We examined the role of neoplasia-related and treatment-induced lymphopenia in the outcome of RT or chemoradiotherapy (CRT) in squamous cell laryngeal cancer. MATERIALS AND METHODS: We retrospectively analyzed a series of 135 laryngeal carcinomas treated with radical or postoperative RT/CRT. Six lymphocyte-related variables were defined and examined: i. lymphocyte counts (LCs) before a brief course of induction chemotherapy, ii. pre-RT LCs, iii. post-RT LCs, iv. pre-RT neutrophil/lymphocyte ratio (N/L), v. pre-RT monocyte/lymphocyte ratio (M/L), and vi. pre-RT platelet/lymphocyte ratio (Pt/L). RESULTS: RT and CRT resulted in a significant decrease of LCs at the end of therapy, and this was significantly more prominent in patients treated with radical intent and neck irradiation (median LC nadir 810/µl vs. 1250/µl; p = .0003). Induction chemotherapy did not intensify the lymphotoxic effect of RT. LCs lower than the 33rd percentile before RT (<1718/µl) and after RT (<720/µl) were significantly linked to poor locoregional progression-free survival (LRFS; p = .02 and p = .08, respectively) and disease-specific overall survival (OS; p = .02 and p = .03, respectively). This was also confirmed multivariate analysis (LRFS: p = .006/HR = 2.41 and p = .08/HR = 1.76, respectively; OS: p = .001/HR = 3.06 and p = .02/HR = 2.07, respectively). High pre-RT N/L, M/L, and Pt/L ratios were also of ominous prognostic relevance. CONCLUSIONS: Both neoplasia-related and RT-induced lymphopenia define the outcome of RT in terms of locoregional failure, incidence of metastasis, and, finally, disease-specific survival of patients with laryngeal cancer. Restoration of pre-RT lymphopenia and protection of peripheral lymphocytes during RT emerge as critical issues that demand therapeutic interventions to maximize the efficacy of RT/CRT in patients with laryngeal cancer.


Assuntos
Quimiorradioterapia , Neoplasias Laríngeas , Linfopenia , Humanos , Linfopenia/etiologia , Neoplasias Laríngeas/terapia , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/mortalidade , Masculino , Feminino , Quimiorradioterapia/efeitos adversos , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Resultado do Tratamento , Adulto , Idoso de 80 Anos ou mais , Contagem de Linfócitos
10.
J Pharm Biomed Anal ; 242: 116033, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377690

RESUMO

Eravacycline (ERC) was approved for clinical use in 2018. It is more potent than other tetracyclines and can overcome resistance, making it an attractive option for combating multidrug-resistant bacterial infections. Intensive pharmacokinetic (PK) studies are currently being conducted to ensure the effectiveness and safety of ERC in various groups of patients, including those undergoing extracorporeal therapies. This study is the first attempt to develop a simple, efficient, and high-throughput immunoassay for quantifying ERC in human or animal serum. BSA-ERC conjugate as immunogen elicited antibody production in rabbits. Monitoring of the immune response and comparison of homologous and heterologous coating antigens allowed selection of immunoreagents and development of an assay that was selective for ERC possessing sensitivity (IC50), dynamic range (IC20-IC80) and detection limit equal to 3.3 ng/mL, 0.27-54 ng/mL and 0.09 ng/mL, respectively. The developed ELISA showed acceptable recovery of ERC (85-105 %) from rabbit and human serum in the clinically relevant concentration range of 0.1-3.0 mg/L. The method was used to quantify serum ERC concentration in the pilot PK study in Soviet chinchilla rabbits. The results were confirmed by HPLC-MS/MS.


Assuntos
Monitoramento de Medicamentos , Espectrometria de Massas em Tandem , Humanos , Coelhos , Animais , Anticorpos , Ensaio de Imunoadsorção Enzimática/métodos , Tetraciclinas , Antígenos
11.
Mov Disord ; 39(2): 339-349, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38014556

RESUMO

BACKGROUND: Recent studies have advanced our understanding of the genetic drivers of Parkinson's disease (PD). Rare variants in more than 20 genes are considered causal for PD, and the latest PD genome-wide association study (GWAS) identified 90 independent risk loci. However, there remains a gap in our understanding of PD genetics outside of the European populations in which the vast majority of these studies were focused. OBJECTIVE: The aim was to identify genetic risk factors for PD in a South Asian population. METHODS: A total of 674 PD subjects predominantly with age of onset (AoO) ≤50 years (encompassing juvenile, young, or early-onset PD) were recruited from 10 specialty movement disorder centers across India over a 2-year period; 1376 control subjects were selected from the reference population GenomeAsia, Phase 2. We performed various case-only and case-control genetic analyses for PD diagnosis and AoO. RESULTS: A genome-wide significant signal for PD diagnosis was identified in the SNCA region, strongly colocalizing with SNCA region signal from European PD GWAS. PD cases with pathogenic mutations in PD genes exhibited, on average, lower PD polygenic risk scores than PD cases lacking any PD gene mutations. Gene burden studies of rare, predicted deleterious variants identified BSN, encoding the presynaptic protein Bassoon that has been previously associated with neurodegenerative disease. CONCLUSIONS: This study constitutes the largest genetic investigation of PD in a South Asian population to date. Future work should seek to expand sample numbers in this population to enable improved statistical power to detect PD genes in this understudied group. © 2023 Denali Therapeutics and The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Doença de Parkinson/diagnóstico , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Mutação
12.
medRxiv ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38076956

RESUMO

Microglia, the innate immune cells of the central nervous system, have been genetically implicated in multiple neurodegenerative diseases. We previously mapped the genetic regulation of gene expression and mRNA splicing in human microglia, identifying several loci where common genetic variants in microglia-specific regulatory elements explain disease risk loci identified by GWAS. However, identifying genetic effects on splicing has been challenging due to the use of short sequencing reads to identify causal isoforms. Here we present the isoform-centric microglia genomic atlas (isoMiGA) which leverages the power of long-read RNA-seq to identify 35,879 novel microglia isoforms. We show that the novel microglia isoforms are involved in stimulation response and brain region specificity. We then quantified the expression of both known and novel isoforms in a multi-ethnic meta-analysis of 555 human microglia short-read RNA-seq samples from 391 donors, the largest to date, and found associations with genetic risk loci in Alzheimer's disease and Parkinson's disease. We nominate several loci that may act through complex changes in isoform and splice site usage.

13.
Insects ; 14(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38132591

RESUMO

Recently, we found that the spongy moth Lymantria dispar L. is susceptible to infection by a Dendrolimus sibiricus cytoplasmic polyhedrosis virus (DsCPV-1). In the present study, we evaluated the pathogenicity of DsCPV-1 against L. dispar larvae and its impact on surviving insects after the infection. Offspring of virally challenged insects were tested for susceptibility to a stress factor (starvation). In addition, we used light microscopy and quantitative polymerase chain reaction (qPCR) to test the ability of DsCPV-1 to be transmitted vertically. We found insect mortality of the L. dispar parents following the infection was positively associated with DsCPV-1 dose. DsCPV-1 was lethal to second-instar L. dispar larvae with a 50% lethal dose (LD50) of 1687 occlusion bodies per larva. No vertical transmission of DsCPV-1 to offspring larvae was detected, while the majority of insect deaths among offspring larvae were caused by microsporidia (Vairimorpha lymantriae), which was harbored by the parents. The offspring of virally challenged parents exhibited a higher number of detected microsporidia compared to the control. Our findings suggest that the application of DsCPV-1 is effective in controlling pests in terms of transgenerational impact following virus exposure.

14.
Molecules ; 28(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38138539

RESUMO

In our ongoing quest to design effective antimicrobial peptides (AMPs), this study aimed to elucidate the mechanisms governing cyclic amphiphilic AMPs and their interactions with membranes. The objective was to discern the nature of these interactions and understand how peptide sequence and structure influence antimicrobial activity. We introduced modifications into the established cyclic AMP peptide, [W4R4], incorporating an extra aromatic hydrophobic residue (W), a positively charged residue (R), or the unique 2,5-diketopiperazine (DKP). This study systematically explored the structure-activity relationships (SARs) of a series of cyclic peptides derived from the [W4R4] scaffold, including the first synthesis and evaluation of [W4R4(DKP)]. Structural, dynamic, hydrophobic, and membrane-binding properties of four cyclic peptides ([W4R4], [W5R4], [W4R5], [W4R4(DKP)]) were explored using molecular dynamics simulations within a DOPC/DOPG lipid bilayer that mimics the bacterial membrane. The results revealed distinct SARs linking antimicrobial activity to parameters such as conformational plasticity, immersion depth in the bilayer, and population of the membrane binding mode. Notably, [W4R5] exhibited an optimal "activity/binding to the bacterial membrane" pattern. This multidisciplinary approach efficiently decoded finely regulated SAR profiles, laying a foundation for the rational design of novel antimicrobial peptides.


Assuntos
Anti-Infecciosos , Peptídeos Cíclicos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Peptídeos Catiônicos Antimicrobianos/química , Anti-Infecciosos/farmacologia , Bicamadas Lipídicas/química , Sequência de Aminoácidos , Bactérias/metabolismo
15.
Biology (Basel) ; 12(10)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37887058

RESUMO

One of the little-studied ways that climate warming or temperature increases in aquaculture could affect aquatic animals is through accelerated aging. This study is dedicated to understanding the principles of molecular and cellular aging in the target tissues of juvenile whitefishes (Yenisei hump-snout whitefish and its hybrid) under the influence of acute heat stress (up to 26 °C), and the effects of thermal preconditioning as pre-adaptation. Non-adapted stressed hump-snout whitefish showed a higher induction threshold for functionally active mitochondria in the blood and a decrease in telomerase activity in the liver after heat shock exposure as a long-term compensatory response to prevent telomere shortening. However, we observed heat-induced telomere shortening in non-adapted hybrids, which can be explained by a decrease in mitochondrial membrane stability and a gradual increase in energy demand, leading to a decrease in protective telomerase activity. The pre-adapted groups of hump-snout whitefish and hybrids showed a long-term or delayed response of telomerase activity to heat shock, which served as a therapeutic mechanism against telomere shortening. We concluded that the telomerase and telomere responses to thermal stress demonstrate plasticity of tolerance limits and greater stability in hump-snout whitefish compared with hybrids.

16.
Elife ; 122023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37874617

RESUMO

Leucine-rich repeat kinase 2 (LRRK2) variants associated with Parkinson's disease (PD) and Crohn's disease lead to increased phosphorylation of its Rab substrates. While it has been recently shown that perturbations in cellular homeostasis including lysosomal damage can increase LRRK2 activity and localization to lysosomes, the molecular mechanisms by which LRRK2 activity is regulated have remained poorly defined. We performed a targeted siRNA screen to identify regulators of LRRK2 activity and identified Rab12 as a novel modulator of LRRK2-dependent phosphorylation of one of its substrates, Rab10. Using a combination of imaging and immunopurification methods to isolate lysosomes, we demonstrated that Rab12 is actively recruited to damaged lysosomes and leads to a local and LRRK2-dependent increase in Rab10 phosphorylation. PD-linked variants, including LRRK2 R1441G and VPS35 D620N, lead to increased recruitment of LRRK2 to the lysosome and a local elevation in lysosomal levels of pT73 Rab10. Together, these data suggest a conserved mechanism by which Rab12, in response to damage or expression of PD-associated variants, facilitates the recruitment of LRRK2 and phosphorylation of its Rab substrate(s) at the lysosome.


Lysosomes are cellular compartments tasked with breaking down large molecules such as lipids or proteins. They perform an essential role in helping cells dispose of obsolete or harmful components; in fact, defects in lysosome function are associated with a range of health conditions. For instance, many genes associated with an increased risk of developing Parkinson's disease code for proteins required for lysosomes to work properly, such as the kinase LRRK2. Previous work has shown that this enzyme gets recruited to the surface of damaged lysosomes, where it can modulate the function of another set of molecular actors by modifying them through a chemical process known as phosphorylation. Such activity is increased in harmful versions of LRRK2 linked to Parkinson's disease. However, the molecular mechanisms which control LRRK2 activity or its recruitment to lysosomes remain unclear. To examine this question, Wang, Bondar et al. first performed a targeted screen to identify proteins that can regulate LRRK2 activity. This revealed that Rab12, one of molecular actors that LRRK2 phosphorylates, can in turn modulate the activity of the enzyme. Further imaging and biochemical experiments then showed that Rab12 is recruited to damaged lysosomes and that this step was in fact necessary for LRRK2 to also relocate to these compartments. The data suggest that this Rab12-driven recruitment process increases the local concentration of LRRK2 near its Rab targets on the membrane of damaged lysosomes, and therefore leads to enhanced LRRK2 activity. Crucially, Wang, Bondar et al. showed that Rab12 also plays a role in the increased LRRK2 activity observed with two Parkinson's disease-linked mutations (one in LRRK2 itself and one in another lysosomal regulator, VPS35), suggesting that increased LRRK2 concentration on lysosomes may be a conserved mechanism that leads to increased LRRK2 activity in disease. Overall, these results highlight a new, Rab12-dependent mechanism that results in enhanced activity at the lysosomal membrane with variants associated with Parkinson's disease, and for LRRK2 in general when lysosomes are damaged. This knowledge will be helpful to develop therapeutic strategies that target LRRK2, and to better understand how increased LRRK2 activity and lysosomal injury may be linked to Parkinson's disease.


Assuntos
Fenômenos Biológicos , Lisossomos , Proteínas rab de Ligação ao GTP , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Lisossomos/metabolismo , Mutação , Fosforilação , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Humanos
17.
J Virol ; 97(10): e0130523, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37823644

RESUMO

IMPORTANCE: A correlation exists between stress and increased episodes of human alpha-herpes virus 1 reactivation from latency. Stress increases corticosteroid levels; consequently, the glucocorticoid receptor (GR) is activated. Recent studies concluded that a GR agonist, but not an antagonist, accelerates productive infection and reactivation from latency. Furthermore, GR and certain stress-induced transcription factors cooperatively transactivate promoters that drive the expression of infected cell protein 0 (ICP0), ICP4, and VP16. This study revealed female mice expressing a GR containing a serine to alanine mutation at position 229 (GRS229A) shed significantly lower levels of infectious virus during explant-induced reactivation compared to male GRS229A or wild-type parental C57BL/6 mice. Furthermore, female GRS229A mice contained fewer VP16 + TG neurons compared to male GRS229A mice or wild-type mice during the early stages of explant-induced reactivation from latency. Collectively, these studies revealed that GR transcriptional activity has female-specific effects, whereas male mice can compensate for the loss of GR transcriptional activation.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Receptores de Glucocorticoides , Ativação Viral , Animais , Feminino , Masculino , Camundongos , Herpes Simples/genética , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/metabolismo , Camundongos Endogâmicos C57BL , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Gânglio Trigeminal , Ubiquitina-Proteína Ligases/metabolismo , Ativação Viral/genética , Latência Viral/genética
18.
Pharmaceuticals (Basel) ; 16(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37630972

RESUMO

The activation of c-Jun N-terminal kinase (JNK) plays an important role in stroke outcomes. Tryptanthrin-6-oxime (TRYP-Ox) is reported to have high affinity for JNK and anti-inflammatory activity and may be of interest as a promising neuroprotective agent. The aim of this study was to investigate the neuroprotective effects of TRYP-Ox in a rat model of transient focal cerebral ischemia (FCI), which involved intraluminal occlusion of the left middle cerebral artery (MCA) for 1 h. Animals in the experimental group were administered intraperitoneal injections of TRYP-Ox 30 min before reperfusion and 23 and 47 h after FCI. Neurological status was assessed 4, 24, and 48 h following FCI onset. Treatment with 5 and 10 mg/kg of TRYP-Ox decreased mean scores of neurological deficits by 35-49 and 46-67% at 24 and 48 h, respectively. At these doses, TRYP-Ox decreased the infarction size by 28-31% at 48 h after FCI. TRYP-Ox (10 mg/kg) reduced the content of interleukin (IL) 1ß and tumor necrosis factor (TNF) in the ischemic core area of the MCA region by 33% and 38%, respectively, and attenuated cerebral edema by 11% in the left hemisphere, which was affected by infarction, and by 6% in the right, contralateral hemisphere 24 h after FCI. TRYP-Ox reduced c-Jun phosphorylation in the MCA pool at 1 h after reperfusion. TRYP-Ox was predicted to have high blood-brain barrier permeability using various calculated descriptors and binary classification trees. Indeed, reactive oxidant production was significantly lower in the brain homogenates from rats treated with TRYP-Ox versus that in control animals. Our data suggest that the neuroprotective activity of TRYP-Ox may be due to the ability of this compound to inhibit JNK and exhibit anti-inflammatory and antioxidant activity. Thus, TRYP-Ox may be considered a promising neuroprotective agent that potentially could be used for the development of new treatment strategies in cerebral ischemia.

19.
RSC Adv ; 13(33): 23147-23157, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37533784

RESUMO

Organic acids are prevalent in the environment and their acidity and the corresponding dissociation constants can change under varying environmental conditions. The impact of nanoconfinement (when acids are confined within nanometer-scale domains) on physicochemical properties of chemical species is poorly understood and is an emerging field of study. By combining infrared and Raman spectroscopies with molecular dynamics (MD) simulations, we quantified the effect of nanoconfinement in silica nanopores on one of the fundamental chemical reactions-the dissociation of organic acids. The pKa of formic and acetic acids confined within cylindrical silica nanopores with 4 nm diameters were measured. MD models were constructed to calculate the shifts in the pKa values of acetic acid nanoconfined within 1, 2, 3, and 4 nm silica slit pores. Both experiments and MD models indicate a decrease in the apparent acid dissociation constants (i.e., increase in the pKa values) when organic acids are nanoconfined. Therefore, nanoconfinement stabilizes the protonated species. We attribute this observation to (1) a decrease in the average dielectric response of nanoconfined aqueous solutions where charge screening may be decreased; or (2) an increase in proton concentration inside nanopores, which would shift the equilibrium towards the protonated form. Overall, the results of this study provide the first quantification of the pKa values for nanoconfined formic and acetic acids and pave the way for a unifying theory predicting the impact of nanoconfinement on acid-base chemistry.

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