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1.
Nature ; 623(7985): 58-65, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914945

RESUMO

To construct tissue-like prosthetic materials, soft electroactive hydrogels are the best candidate owing to their physiological mechanical modulus, low electrical resistance and bidirectional stimulating and recording capability of electrophysiological signals from biological tissues1,2. Nevertheless, until now, bioelectronic devices for such prostheses have been patch type, which cannot be applied onto rough, narrow or deep tissue surfaces3-5. Here we present an injectable tissue prosthesis with instantaneous bidirectional electrical conduction in the neuromuscular system. The soft and injectable prosthesis is composed of a biocompatible hydrogel with unique phenylborate-mediated multiple crosslinking, such as irreversible yet freely rearrangeable biphenyl bonds and reversible coordinate bonds with conductive gold nanoparticles formed in situ by cross-coupling. Closed-loop robot-assisted rehabilitation by injecting this prosthetic material is successfully demonstrated in the early stage of severe muscle injury in rats, and accelerated tissue repair is achieved in the later stage.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Próteses e Implantes , Ferimentos e Lesões , Animais , Ratos , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Condutividade Elétrica , Ouro/química , Hidrogéis/administração & dosagem , Hidrogéis/química , Hidrogéis/uso terapêutico , Nanopartículas Metálicas/química , Músculos/lesões , Músculos/inervação , Robótica , Ferimentos e Lesões/reabilitação , Ferimentos e Lesões/cirurgia
2.
Proc Natl Acad Sci U S A ; 120(33): e2300036120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549292

RESUMO

While the world is rapidly transforming into a superaging society, pharmaceutical approaches to treat sarcopenia have hitherto not been successful due to their insufficient efficacy and failure to specifically target skeletal muscle cells (skMCs). Although electrical stimulation (ES) is emerging as an alternative intervention, its efficacy toward treating sarcopenia remains unexplored. In this study, we demonstrate a silver electroceutical technology with the potential to treat sarcopenia. First, we developed a high-throughput ES screening platform that can simultaneously stimulate 15 independent conditions, while utilizing only a small number of human-derived primary aged/young skMCs (hAskMC/hYskMC). The in vitro screening showed that specific ES conditions induced hypertrophy and rejuvenation in hAskMCs, and the optimal ES frequency in hAskMCs was different from that in hYskMCs. When applied to aged mice in vivo, specific ES conditions improved the prevalence and thickness of Type IIA fibers, along with biomechanical attributes, toward a younger skMC phenotype. This study is expected to pave the way toward an electroceutical treatment for sarcopenia with minimal side effects and help realize personalized bioelectronic medicine.


Assuntos
Sarcopenia , Animais , Humanos , Camundongos , Fibras Musculares Esqueléticas , Músculo Esquelético/fisiologia , Fenótipo , Sarcopenia/terapia , Prata
3.
Med Microbiol Immunol ; 213(1): 16, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033094

RESUMO

Melioidosis is a severe infectious disease caused by Burkholderia pseudomallei, an intracellular pathogen with a high mortality rate and significant antibiotic resistance. The high mortality rate and resistance to antibiotics have drawn considerable attention from researchers studying melioidosis. This study evaluated the effects of various concentrations (75, 50, and 25 µg/mL) of promethazine hydrochloride (PTZ), a potent antihistamine, on biofilm formation and lipase activity after 24 h of exposure to B. thailandensis E264. A concentration-dependent decrease in both biofilm biomass and lipase activity was observed. RT-PCR analysis revealed that PTZ treatment not only made the biofilm structure loose but also reduced the expression of btaR1, btaR2, btaR3, and scmR. Single gene knockouts of quorum sensing (QS) receptor proteins (∆btaR1, ∆btaR2, and ∆btaR3) were successfully constructed. Deletion of btaR1 affected biofilm formation in B. thailandensis, while deletion of btaR2 and btaR3 led to reduced lipase activity. Molecular docking and biological performance results demonstrated that PTZ inhibits biofilm formation and lipase activity by suppressing the expression of QS-regulated genes. This study found that repositioning PTZ reduced biofilm formation in B. thailandensis E264, suggesting a potential new approach for combating melioidosis.


Assuntos
Biofilmes , Burkholderia , Reposicionamento de Medicamentos , Prometazina , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Burkholderia/efeitos dos fármacos , Burkholderia/fisiologia , Burkholderia/genética , Prometazina/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Lipase/metabolismo , Lipase/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Percepção de Quorum/efeitos dos fármacos
4.
Mol Divers ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739229

RESUMO

To discover new Werner (WRN) helicase inhibitors, a series of N-aryl-2-trifluoromethyl-quinazoline-4-amine derivatives were designed and synthesized through a structural optimization strategy, and the anticancer activities of 25 new target compounds against PC3, K562, and HeLa cell lines were evaluated by the MTT assay. Some of these compounds exhibited excellent inhibitory activity against three different cancer cell lines. Compounds 6a, 8i, and 13a showed better antiproliferative activity against K562 cells, with IC50 values of 3871.5, 613.6 and 134.7 nM, respectively, than did paclitaxel (35.6 nM), doxorubicin (2689.0 nM), and NSC 617145 (20.3 nM). To further verify whether the antiproliferative activity of these compounds is dependent on WRN, PC3 cells overexpressing WRN (PC3-WRN) were constructed to further study their antiproliferative potency in vitro, and the inhibition ratio and IC20 values showed that compounds 6a, 8i, and 13a were more sensitive to PC3-WRN than were the control group cells (PC3-NC). The IC20 ratios of compounds 6a, 8i, and 13a to PC3-NC and PC3-WRN were 94.3, 153.4 and 505.5, respectively. According to the docking results, the compounds 6a, 8i, and 13a overlapped well with the binding pocket of 6YHR. Further study demonstrated that among the tested compounds, 13a was the most sensitive to PC3-WRN. In summary, our research identified a series of N-aryl-2-trifluoromethyl-quinazoline-4-amine derivatives as potential WRN-dependent anticancer agents.

5.
Hum Resour Health ; 22(1): 39, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872223

RESUMO

BACKGROUND: According to previous studies, stress and job burnout among medical personnel increased during the COVID-19 pandemic. This study analyzed the effect of the experience of COVID-19 response work on the intention of municipal hospital staffs to leave their workplaces during the pandemic. METHODS: The 3556 employees who had worked for more than 1 year at one of the eight Seoul Municipal Hospitals that either provided inpatient treatment for quarantined COVID-19 patients or operated as screening clinics were taken as the study population. In total, 1227 employees completed a web or mobile survey between October 21 and November 18, 2020. A chi-squared test was performed to confirm the difference in the distribution of turnover intention depending on whether the employees performed COVID-19 response tasks. Multiple logistic regression analyses were performed to determine the factors that affected the intention to leave. RESULTS: Of the 1227 respondents, 761 (62.0%) were frontline workers who were the first line of response to COVID-19. Experience with COVID-19 response tasks (OR = 1.59, p = 0.003) was significantly associated with the intention to leave. Additionally, the probability of turnover intention was significantly higher among workers aged 20-29 years (OR = 2.11, p = 0.038) and 40-49 years (OR = 1.57, p = 0.048), unmarried individuals (OR = 1.66, p = 0.005), doctors (OR = 2.41, p = 0.010), nurses (OR = 1.59, p = 0.036), and technical staff members (OR = 2.22, p = 0.009). High turnover intention was found among those who experienced high levels of burnout (OR = 2.03, p < 0.001) and those working in non-directly managed municipal hospitals (OR = 1.87, p = 0.018). CONCLUSION: Employees directly involved in COVID-19 response work displayed higher turnover intention. Various personal, job, and organizational factors significantly influenced employees' intentions to leave their positions in dedicated COVID-19 hospitals. These findings suggest the necessity of introducing management programs to aid workers who have experienced sudden changes in their duties and loss of autonomy while performing COVID-19 response tasks.


Assuntos
Esgotamento Profissional , COVID-19 , Intenção , Reorganização de Recursos Humanos , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Reorganização de Recursos Humanos/estatística & dados numéricos , Adulto , Masculino , Feminino , Esgotamento Profissional/epidemiologia , Pessoa de Meia-Idade , Seul , Inquéritos e Questionários , Recursos Humanos em Hospital/psicologia , Adulto Jovem , Local de Trabalho/psicologia , Pandemias , Satisfação no Emprego
6.
Curr Issues Mol Biol ; 45(12): 9926-9942, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38132466

RESUMO

Microglia-induced inflammatory signaling and neuronal oxidative stress are mutually reinforcing processes central to the pathogenesis of neurodegenerative diseases. Recent studies have shown that extracts of dried Pheretima aspergillum (Lumbricus) can inhibit tissue fibrosis, mitochondrial damage, and asthma. However, the effects of Lumbricus extracts on neuroinflammation and neuronal damage have not been previously studied. Therefore, to evaluate the therapeutic potential of Lumbricus extract for neurodegenerative diseases, the current study assessed the extract's anti-inflammatory and antioxidant activities in BV2 microglial cultures stimulated with lipopolysaccharide (LPS) along with its neuroprotective efficacy in mouse hippocampal HT22 cell cultures treated with excess glutamate. Lumbricus extract dose-dependently inhibited the LPS-induced production of multiple proinflammatory cytokines (tumor necrosis factor-α, interleukin (IL)-6, and IL-1ß) and reversed the upregulation of proinflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2). Lumbricus also activated the antioxidative nuclear factor erythroid 2-relayed factor 2/heme oxygenase-1 pathway and inhibited LPS-induced activation of the nuclear factor-κB/mitogen-activated protein kinases/NOD-like receptor family pyrin domain containing 3 inflammatory pathway. In addition, Lumbricus extract suppressed the glutamate-induced necrotic and apoptotic death of HT22 cells, effects associated with upregulated expression of antiapoptotic proteins, downregulation of pro-apoptotic proteins, and reduced accumulation of reactive oxygen species. Chromatography revealed that the Lumbricus extract contained uracil, hypoxanthine, uridine, xanthine, adenosine, inosine, and guanosine. Its effects against microglial activation and excitotoxic neuronal death reported herein support the therapeutic potential of Lumbricus for neurodegenerative diseases.

7.
Curr Issues Mol Biol ; 44(12): 5902-5914, 2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36547063

RESUMO

Arecae Pericarpium has been found to exert anti-migraine, antidepressant, and antioxidative effects. However, the mechanisms involved are unclear. This study explored the possibility that Arecae Pericarpium ethanol extract (APE) exerts neuroprotective effects against oxidative stress-induced neuronal cell death. Since glutamate excitotoxicity has been implicated in the pathogenesis and development of several neurodegenerative disorders, we explored the mechanisms of action of APE on oxidative stress-induced by glutamate. Our results revealed that pretreatment with APE prevents glutamate-induced HT22 cell death. APE also reduced both the levels of intracellular reactive oxygen species and the apoptosis of cells, while maintaining glutamate-induced mitochondrial membrane potentials. Western blotting showed that pretreatment with APE facilitates the upregulation of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) phosphorylation; the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf-2); and the production of antioxidant enzymes, including catalase, glutamate-cysteine ligase catalytic subunits, NAD(P)H quinone oxidoreductase 1, and heme oxygenase (HO)-1. The administration of LY294002, a PI3K/Akt inhibitor, attenuated the neuroprotective effects of APE on oxidative stress-induced neuronal cell damage. This allowed us to infer that the protective effects of APE on oxidative damage to cells can be attributed to the PI3K/Akt-mediated Nrf-2/HO-1 signaling pathway.

8.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077077

RESUMO

Plant C2-domain abscisic acid-related (CAR) protein family plays an important role in plant growth, abiotic stress responses, and defense regulation. In this study, we cloned the IbCAR1 by homologous cloning method from the transcriptomic data of Xuzishu8, which is a sweet potato cultivar with dark-purple flesh. This gene was expressed in all tissues of sweet potato, with the highest expression level in leaf tissue, and it could be induced by NaCl and ABA. Subcellular localization analyses indicated that IbCAR1 was localized in the nucleus and plasma membrane. The PI staining experiment revealed the distinctive root cell membrane integrity of overexpressed transgenic lines upon salt stress. Salt stress significantly increased the contents of proline, ABA, and the activity of superoxide dismutase (SOD), whereas the content of malondialdehyde (MDA) was decreased in overexpressed lines. On the contrary, RNA interference plants showed sensitivity to salt stress. Overexpression of IbCAR1 in sweet potatoes could improve the salt tolerance of plants, while the RNAi of IbCAR1 significantly increased sensitivity to salt stress in sweet potatoes. Meanwhile, the genes involved in ABA biosynthesis, stress response, and reactive oxygen species (ROS)-scavenging system were upregulated in overexpressed lines under salt stress. Taken together, these results demonstrated that IbCAR1 plays a positive role in salt tolerance by relying on the ABA signal transduction pathway, activating the ROS-scavenging system in sweet potatoes.


Assuntos
Ipomoea batatas , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genética
9.
Int J Mol Sci ; 23(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36232743

RESUMO

Glutamate-induced neural toxicity in autophagic neuron death is partially mediated by increased oxidative stress. Therefore, reducing oxidative stress in the brain is critical for treating or preventing neurodegenerative diseases. Selaginella tamariscina is a traditional medicinal plant for treating gastrointestinal bleeding, hematuria, leucorrhea, inflammation, chronic hepatitis, gout, and hyperuricemia. We investigate the inhibitory effects of Selaginella tamariscina ethanol extract (STE) on neurotoxicity and autophagic cell death in glutamate-exposed HT22 mouse hippocampal cells. STE significantly increased cell viability and mitochondrial membrane potential and decreased the expression of reactive oxygen species, lactate dehydrogenase release, and cell apoptosis in glutamate-exposed HT22 cells. In addition, while glutamate induced the excessive activation of mitophagy, STE attenuated glutamate-induced light chain (LC) 3 II and Beclin-1 expression and increased p62 expression. Furthermore, STE strongly enhanced the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) phosphorylation activation. STE strongly inhibited glutamate-induced autophagy by activating the PI3K/Akt/mTOR signaling pathway. In contrast, the addition of LY294002, a PI3K/Akt inhibitor, remarkably suppressed cell viability and p-Akt and p62 expression, while markedly increasing the expression of LC3 II and Beclin-1. Our findings indicate that autophagy inhibition by activating PI3K/Akt/mTOR phosphorylation levels could be responsible for the neuroprotective effects of STE on glutamate neuronal damage.


Assuntos
Morte Celular Autofágica , Fármacos Neuroprotetores , Selaginellaceae , Animais , Autofagia , Proteína Beclina-1/farmacologia , Etanol/farmacologia , Ácido Glutâmico/toxicidade , Lactato Desidrogenases/metabolismo , Mamíferos/metabolismo , Camundongos , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Selaginellaceae/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
10.
J Xray Sci Technol ; 30(4): 767-776, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35527621

RESUMO

PURPOSE: To establish a machine-learning (ML) model based on coronary computed tomography angiography (CTA) images for evaluating myocardial ischemia in patients diagnosed with coronary atherosclerosis. METHODS: This retrospective analysis includes CTA images acquired from 110 patients. Among them, 58 have myocardial ischemia and 52 have normal myocardial blood supply. The patients are divided into training and test datasets with a ratio 7 : 3. Deep learning model-based CQK software is used to automatically segment myocardium on CTA images and extract texture features. Then, seven ML models are constructed to classify between myocardial ischemia and normal myocardial blood supply cases. Predictive performance and stability of the classifiers are determined by receiver operating characteristic curve with cross validation. The optimal ML model is then validated using an independent test dataset. RESULTS: Accuracy and areas under ROC curves (AUC) obtained from the support vector machine with extreme gradient boosting linear method are 0.821 and 0.777, respectively, while accuracy and AUC achieved by the neural network (NN) method are 0.818 and 0.757, respectively. The naive Bayes model yields the highest sensitivity (0.942), and the random forest model yields the highest specificity (0.85). The k-nearest neighbors model yields the lowest accuracy (0.74). Additionally, NN model demonstrates the lowest relative standard deviations (0.16 for accuracy and 0.08 for AUC) indicating the high stability of this model, and its AUC applying to the independent test dataset is 0.72. CONCLUSION: The NN model demonstrates the best performance in predicting myocardial ischemia using radiomics features computed from CTA images, which suggests that this ML model has promising potential in guiding clinical decision-making.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Teorema de Bayes , Humanos , Aprendizado de Máquina , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
J Neurosci ; 40(27): 5196-5207, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32482639

RESUMO

Elevations in estrogen (17ß-estradiol, E2) are associated with increased alcohol drinking by women and experimentally in rodents. E2 alters the activity of the dopamine system, including the VTA and its projection targets, which plays an important role in binge drinking. A previous study demonstrated that, during high E2 states, VTA neurons in female mice are more sensitive to ethanol excitation. However, the mechanisms responsible for the ability of E2 to enhance ethanol sensitivity of VTA neurons have not been investigated. In this study, we used selective agonists and antagonists to examine the role of ER subtypes (ERα and ERß) in regulating the ethanol sensitivity of VTA neurons in female mice and found that ERα promotes the enhanced ethanol response of VTA neurons. We also demonstrated that enhancement of ethanol excitation requires the activity of the metabotropic glutamate receptor, mGluR1, which is known to couple with ERα at the plasma membrane. To investigate the behavioral relevance of these findings, we administered lentivirus-expressing short hairpin RNAs targeting either ERα or ERß into the VTA and found that knockdown of each receptor in the VTA reduced binge-like ethanol drinking in female, but not male, mice. Reducing ERα in the VTA had a more dramatic effect on binge-like drinking than reducing ERß, consistent with the ability of ERα to alter ethanol sensitivity of VTA neurons. These results provide important insight into sex-specific mechanisms that drive excessive alcohol drinking.SIGNIFICANCE STATEMENT Estrogen has potent effects on the dopamine system and increases the vulnerability of females to develop addiction to substances, such as alcohol. We investigated the mechanisms by which estrogen increases the response of neurons in the VTA to ethanol. We found that activation of the ERα increased the ethanol-induced excitation of VTA neurons. 17ß-Estradiol-mediated enhancement of ethanol-induced excitation required the metabotropic glutamate receptor mGluR1. We also demonstrated that ERs in the VTA regulate binge-like alcohol drinking by female, but not male, mice. The influence of ERs on binge drinking in female mice suggests that treatments for alcohol use disorder in women may need to account for this sex difference.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Depressores do Sistema Nervoso Central/farmacologia , Receptor alfa de Estrogênio/metabolismo , Etanol/farmacologia , Neurônios/efeitos dos fármacos , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Antagonistas de Estrogênios/farmacologia , Receptor alfa de Estrogênio/agonistas , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/agonistas , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Receptores de AMPA/metabolismo , Área Tegmentar Ventral/citologia
12.
Alcohol Clin Exp Res ; 45(7): 1348-1358, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33960499

RESUMO

BACKGROUND: Alcohol excites neurons of the ventral tegmental area (VTA) and the release of dopamine from these neurons is a key event in ethanol (EtOH)-induced reward and reinforcement. Many mechanisms have been proposed to explain EtOH's actions on neurons of the VTA, but antagonists generally do not eliminate the EtOH-induced excitation of VTA neurons. We have previously demonstrated that the ion channel KCNK13 plays an important role in the EtOH-related excitation of mouse VTA neurons. Here, we elaborate on that finding and further assess the importance of KCNK13 in rats. METHODS: Rats (Sprague-Dawley and Fisher 344) were used in these studies. In addition to single-unit electrophysiology in brain slices, we used quantitative PCR and immunohistochemistry to discern the effects of EtOH and the brain slice preparation method on the expression levels of the Kcnk13 gene and KCNK13 protein. RESULTS: Immunohistochemistry demonstrated that the levels of KCNK13 were significantly reduced during procedures normally used to prepare brain slices for electrophysiology, with a reduction of about 75% in KCNK13 protein at the time that electrophysiological recordings would normally be made. Extracellular recordings demonstrated that EtOH-induced excitation of VTA neurons was reduced after knockdown of Kcnk13 using a small interfering RNA (siRNA) delivered via the recording micropipette. Real-time PCR demonstrated that the expression of Kcnk13 was altered in a time-dependent manner after alcohol withdrawal. CONCLUSIONS: KCNK13 plays an important role in EtOH-induced stimulation of rat VTA neurons and is dynamically regulated by cell damage and EtOH exposure, and during withdrawal. KCNK13 is a novel alcohol-sensitive protein, and further investigation of this channel may offer new avenues for the development of agents useful in altering the rewarding effect of alcohol.


Assuntos
Etanol/farmacologia , Canais de Potássio de Domínios Poros em Tandem/fisiologia , Área Tegmentar Ventral/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Gadolínio/farmacologia , Expressão Gênica/efeitos dos fármacos , Isoflurano/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Canais de Potássio de Domínios Poros em Tandem/análise , Canais de Potássio de Domínios Poros em Tandem/genética , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Endogâmicos F344 , Ratos Sprague-Dawley , Área Tegmentar Ventral/química , Área Tegmentar Ventral/fisiologia
13.
Mediators Inflamm ; 2021: 6687089, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790692

RESUMO

The activation of microglial cells and their subsequent neuroinflammatory reactions are related to various degenerative brain diseases. Therefore, the regulation of microglial cell activation is an important point for the research of therapeutic agents for treating or preventing neurodegenerative disorders. Saussureae Radix (SR) is the root of Saussurea lappa Clarke, and it has been used for a long time as an herbal medicine in East Asia to treat indigestion and inflammation of the digestive system. In previous studies, however, the effect of SR ethanolic extract on microglial cell-mediated neuroinflammation was not fully explained. In this study, we explored the antineuroinflammatory activities and molecular mechanisms of SR in microglial cells stimulated with LPS (lipopolysaccharide). Our results illustrated that SR does not cause cytotoxicity and significantly weakens the production of nitric oxide (NO) and inflammatory cytokines. SR treatment also inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase- (COX-) 2, induced heme oxygenase- (HO-) 1, and activated the nuclear factor erythroid 2-related factor 2 (Nrf-2) pathway. In addition, SR significantly repressed the transcriptional activities of the nuclear factor- (NF-) κB and activator protein- (AP-) 1. Furthermore, SR effectively inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) and Janus kinase (JAK)/signal transducer and activator of transcription (STAT). Isolation and high-performance liquid chromatography (HPLC) analysis indicated two major sesquiterpenoids (costunolide and dehydrocostuslactone). These compounds significantly inhibited the production of neuroinflammatory mediators and induced HO-1 expression. These findings show that SR could be a potential candidate for the treatment of inflammation-related degenerative brain diseases.


Assuntos
Lipopolissacarídeos , Microglia , Animais , Ciclo-Oxigenase 2/metabolismo , Heme Oxigenase-1/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , NF-kappa B/metabolismo , Doenças Neuroinflamatórias , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
14.
J Xray Sci Technol ; 29(6): 1149-1160, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34657848

RESUMO

OBJECTIVE: To develop and test an optimal machine learning model based on the enhanced computed tomography (CT) to preoperatively predict pathological grade of clear cell renal cell carcinoma (ccRCC). METHODS: A retrospective analysis of 53 pathologically confirmed cases of ccRCC was performed and 25 consecutive ccRCC cases were selected as a prospective testing set. All patients underwent routine preoperative abdominal CT plain and enhanced scans. Renal tumor lesions were segmented on arterial phase images and 396 radiomics features were extracted. In the training set, seven discrimination classifiers for high- and low-grade ccRCCs were constructed based on seven different machine learning models, respectively, and their performance and stability for predicting ccRCC grades were evaluated through receiver operating characteristic (ROC) analysis and cross-validation. Prediction accuracy and area under ROC curve were used as evaluation indices. Finally, the diagnostic efficacy of the optimal model was verified in the testing set. RESULTS: The accuracies and AUC values achieved by support vector machine with radial basis function kernel (svmRadial), random forest and naïve Bayesian models were 0.860±0.158 and 0.919±0.118, 0.840±0.160 and 0.915±0.138, 0.839±0.147 and 0.921±0.133, respectively, which showed high predictive performance, whereas K-nearest neighborhood model yielded lower accuracy of 0.720±0.188 and lower AUC value of 0.810±0.150. Additionally, svmRadial had smallest relative standard deviation (RSD, 0.13 for AUC, 0.17 for accuracy), which indicates higher stability. CONCLUSION: svmRadial performs best in predicting pathological grades of ccRCC using radiomics features computed from the preoperative CT images, and thus may have high clinical potential in guiding preoperative decision.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Teorema de Bayes , Carcinoma de Células Renais/diagnóstico por imagem , Humanos , Neoplasias Renais/diagnóstico por imagem , Aprendizado de Máquina , Estudos Prospectivos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
15.
J Am Chem Soc ; 142(6): 3184-3195, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31951699

RESUMO

We report an arene-containing chiral primary amine as a dual aminocatalyst and ligand: the π-coordinating aminocatalyst/palladium synergistic catalysis for asymmetric allylic alkylation of α-branched ß-ketocarbonyls. The use of arene-containing chiral primary amine catalyst led to not only enhanced reaction rate but also reversed chiral induction compared with its sterically bulky derivative. Both enantiomers of the allylic adducts bearing acyclic all-carbon quaternary stereocenters could be obtained from the same configured chiral aminocatalysts with high efficiency and excellent regio-, stereo-, and enantioselectivity. Mechanistic studies revealed a distinctive Pd-arene π-coordination mode for effective catalysis. The π-coordinating chiral primary amine catalyst could be successfully applied in the asymmetric allylation reactions of vinylethylene carbonates, vinyl epoxides, or simple allylic alcohols.

16.
Mediators Inflamm ; 2019: 9184769, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31565034

RESUMO

Hoveniae semen seu fructus (HSF, fruit and seed of Hovenia dulcis Thunb) is an important traditional herbal medicine and food supplement in East Asia for the treatment of liver diseases, alcohol poisoning, obesity, allergy, and cancer. HSF has also been reported to have anti-inflammatory activity, but the cellular mechanism of action is not fully understood. We assessed the anti-inflammatory properties of an HSF ethanol (HSFE) extract and explored its precise mechanism. The ability of HSFE to suppress inflammatory responses was investigated in a murine macrophage cell line, RAW 264.7, and mouse primary macrophages. Secretions of NO, proinflammatory cytokines, inflammatory factors, and related proteins were measured using the Griess assay, ELISA, Western blot analysis, and real-time PCR, respectively. In addition, the main components of HSFE were analyzed by HPLC, and their anti-inflammatory activity was confirmed. Our results showed that pretreatment of HSFE markedly reduced the expression of NO and iNOS without causing cytotoxicity and significantly attenuated secretion of proinflammatory cytokines, including TNF-α, IL-6, and IL-1ß. In addition, HSFE strongly suppressed phosphorylation of MAPK and decreased the activation of AP-1, JAK2/STAT, and NF-κB in LPS-stimulated RAW 264.7 cells in a concentration-dependent manner. Furthermore, HSFE strongly suppressed the inflammatory cytokine levels in mouse peritoneal macrophages. Also, as a result of HPLC analysis, three main components, ampelopsin, taxifolin, and myricetin, were identified in the HSFE extract, and each compound effectively inhibited the secretion of inflammatory mediators induced by LPS. These findings show that HSFE exerts anti-inflammatory effects by suppressing the activation of MAPK, AP-1, JAK2/STAT, and NF-κB signaling pathways in LPS-stimulated macrophages. In addition, the anti-inflammatory efficacy of HSFE appears to be closely related to the action of the three main components. Therefore, HSFE appears to be a promising candidate for the treatment of inflammatory diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Etanol/química , Extratos Vegetais/uso terapêutico , Animais , Citocinas/sangue , Lipopolissacarídeos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células RAW 264.7 , Fator de Transcrição AP-1/sangue
17.
Int J Mol Sci ; 20(16)2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31426492

RESUMO

Microglial activation and the resulting neuroinflammation are associated with a variety of brain diseases, such as Alzheimer's disease and Parkinson's disease. Thus, the control of microglial activation is an important factor in the development of drugs that can treat or prevent inflammation-related neurodegenerative disorders. Atractylodis Rhizoma Alba (ARA) has been reported to exhibit antioxidant, gastroprotective, and anti-inflammatory effects. However, the effects of ARA ethanolic extract (ARAE) on microglia-mediated neuroinflammation have not been fully elucidated. In this work, we explored the anti-neuroinflammatory properties and underlying molecular mechanisms of ARAE in lipopolysaccharide (LPS)-stimulated microglial BV2 cells. Our results showed that ARAE significantly attenuates the production of nitric oxide (NO) and inflammatory cytokines induced by LPS. ARAE treatment also inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 without causing cytotoxicity. ARAE markedly attenuated the transcriptional activities of nuclear factor (NF)-κB and mitogen-activated protein kinases (MAPK) phosphorylation, and induced heme oxygenase (HO)-1 expression. High-performance liquid chromatography (HPLC) analysis showed that ARAE contains three main components-atractylenolide I, atractylenolide III, and atractylodin-all compounds that significantly inhibit the production of inflammatory factors. These findings indicate that ARAE may be a potential therapeutic agent for the treatment of inflammation-related neurodegenerative diseases.


Assuntos
Inflamação/tratamento farmacológico , Lactonas/farmacologia , Microglia/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Preparações de Plantas/farmacologia , Sesquiterpenos/farmacologia , Animais , Asteraceae/química , Linhagem Celular , Ciclo-Oxigenase 2/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Heme Oxigenase-1/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/metabolismo , Microglia/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Preparações de Plantas/química , Raízes de Plantas/química , Transdução de Sinais
18.
Molecules ; 24(20)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635294

RESUMO

Angelicae Gigantis Radix (AGR) has been widely used as a traditional medicine in East Asia. The effects of AGR on neuroinflammation have not previously been studied in detail. In the study presented here, we investigated the antineuroinflammatory properties of this herb and its mechanism of operation. The effects of AGR on neuroinflammation were studied by measuring the production of inflammatory factors and related enzymes, and analyzing the expression levels of proteins and genes involved its activity, in lipopolysaccharide (LPS)-stimulated BV2 microglia. We found that AGR pretreatment strongly inhibits the production of nitric oxide (NO), cytokines, and the enzymes inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2, and effectively induces the activation of heme oxygenase (HO)-1 and its regulator, nuclear factor erythroid 2-related factor 2 (Nrf-2). We also found that AGR effectively regulates the activation of nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK). We confirmed the antineuroinflammatory effects of the main constituents of the plant as identified by high-performance liquid chromatography (HPLC). Our results indicate that the neuroinflammation inhibitory activity of AGR occurs through inhibition of NF-κB and MAPK and activation of Nrf-2.


Assuntos
Angelica/química , Etanol/farmacologia , Lipopolissacarídeos/efeitos adversos , Microglia/citologia , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Etanol/química , Regulação da Expressão Gênica/efeitos dos fármacos , Medicina Tradicional do Leste Asiático , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Transdução de Sinais
19.
Alcohol Clin Exp Res ; 42(11): 2160-2171, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30103280

RESUMO

BACKGROUND: The ventral tegmental area (VTA) is important for alcohol-related reward and reinforcement. Mouse VTA neurons are hyposensitive to γ-aminobutyric acid (GABA) during ethanol (EtOH) withdrawal, and GABA responsiveness is normalized by in vitro treatment with histone deacetylase inhibitors (HDACi). The present study examined the effect of a systemically administered HDACi, suberanilohydroxamic acid (SAHA) on GABA sensitivity, and related molecular changes in VTA neurons during withdrawal after chronic EtOH intake in rats. METHODS: Sprague Dawley male adult rats were fed with Lieber-DeCarli diet (9% EtOH or control diet) for 16 days. Experimental groups included control diet-fed and EtOH diet-fed (0- or 24-hour withdrawal) rats treated with either SAHA or vehicle injection. Single-unit recordings were used to measure the response of VTA neurons to GABA. Immunohistochemistry was performed to examine levels of HDAC2, acetylated histone H3 lysine 9 (acH3K9), and GABAA receptor α1 and α5 subunits in the VTA; quantitative polymerase chain reaction was performed to examine the mRNA levels of HDAC2 and GABAA receptor subunits. RESULTS: VTA neurons from the withdrawal group exhibited GABA hyposensitivity. In vivo SAHA treatment 2 hours before sacrifice normalized the sensitivity of VTA neurons to GABA. EtOH withdrawal was associated with increased HDAC2 and decreased acH3K9 protein levels; SAHA treatment normalized acH3K9 levels. Interestingly, no significant change was observed in the mRNA levels of HDAC2. The mRNA levels, but not protein levels, of GABAA receptor α1 and α5 subunits were increased during withdrawal. CONCLUSIONS: Withdrawal from chronic EtOH exposure results in a decrease in GABA-mediated inhibition, and this GABA hyposensitivity is normalized by in vivo SAHA treatment. Disruption of signaling in the VTA produced by alteration of GABA neurotransmission could be 1 neuroadaptive physiological process leading to craving and relapse. These results suggest that HDACi pharmacotherapy with agents like SAHA might be an effective treatment for alcoholism.


Assuntos
GABAérgicos/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Área Tegmentar Ventral/efeitos dos fármacos , Vorinostat/uso terapêutico , Ácido gama-Aminobutírico/farmacologia , Animais , Dieta , Histona Desacetilase 2/metabolismo , Histonas/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/biossíntese , Receptores de GABA-A/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo
20.
Org Biomol Chem ; 16(25): 4728-4733, 2018 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-29901064

RESUMO

A facile and efficient protocol for rhodium-catalyzed amination of quinoline N-oxides at the C-8 position using simple and commercially available trifluoroacetamide as the amino source has been developed, which proceeds with perfect regioselectivity at room temperature and short reaction times. This catalytic system is highly convenient on a gram scale. The desired products feature diverse functional group tolerance with good to excellent yields.

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