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1.
Accid Anal Prev ; 205: 107687, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943983

RESUMO

Autonomous driving technology has the potential to significantly reduce the number of traffic accidents. However, before achieving full automation, drivers still need to take control of the vehicle in complex and diverse scenarios that the autonomous driving system cannot handle. Therefore, appropriate takeover request (TOR) designs are necessary to enhance takeover performance and driving safety. This study focuses on takeover tasks in hazard scenarios with varied hazard visibility, which can be categorized as overt hazards and covert hazards. Through ergonomic experiments, the impact of TOR interface visual information, including takeover warning, hazard direction, and time to collision, on takeover performance is investigated, and specific analyses are conducted using eye-tracking data. The following conclusions are drawn from the experiments: (1) The visibility of hazards significantly affects takeover performance. (2) Providing more TOR visual information in hazards with different visibility has varying effects on drivers' visual attention allocation but can improve takeover performance. (3) More TOR visual information helps reduce takeover workload and increase human-machine trust. Based on these findings, this paper proposes the following TOR visual interface design strategies: (1) In overt hazard scenarios, only takeover warning is necessary, as additional visual information may distract drivers' attention. (2) In covert hazard scenarios, the TOR visual interface should better assist drivers in understanding the current hazard situation by providing information on hazard direction and time to collision to enhance takeover performance.

2.
Nat Commun ; 15(1): 5152, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886396

RESUMO

In many cancers, a stem-like cell subpopulation mediates tumor initiation, dissemination and drug resistance. Here, we report that cancer stem cell (CSC) abundance is transcriptionally regulated by C-terminally phosphorylated p27 (p27pT157pT198). Mechanistically, this arises through p27 co-recruitment with STAT3/CBP to gene regulators of CSC self-renewal including MYC, the Notch ligand JAG1, and ANGPTL4. p27pTpT/STAT3 also recruits a SIN3A/HDAC1 complex to co-repress the Pyk2 inhibitor, PTPN12. Pyk2, in turn, activates STAT3, creating a feed-forward loop increasing stem-like properties in vitro and tumor-initiating stem cells in vivo. The p27-activated gene profile is over-represented in STAT3 activated human breast cancers. Furthermore, mammary transgenic expression of phosphomimetic, cyclin-CDK-binding defective p27 (p27CK-DD) increases mammary duct branching morphogenesis, yielding hyperplasia and microinvasive cancers that can metastasize to liver, further supporting a role for p27pTpT in CSC expansion. Thus, p27pTpT interacts with STAT3, driving transcriptional programs governing stem cell expansion or maintenance in normal and cancer tissues.


Assuntos
Neoplasias da Mama , Inibidor de Quinase Dependente de Ciclina p27 , Hiperplasia , Células-Tronco Neoplásicas , Fator de Transcrição STAT3 , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Humanos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/genética , Animais , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Feminino , Fosforilação , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Hiperplasia/metabolismo , Camundongos , Regulação Neoplásica da Expressão Gênica , Autorrenovação Celular/genética , Linhagem Celular Tumoral , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Animais/citologia , Proteína Jagged-1/metabolismo , Proteína Jagged-1/genética
3.
Metab Brain Dis ; 38(4): 1249-1259, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36662413

RESUMO

Vagus nerve stimulation through the action of acetylcholine can modulate inflammatory responses and metabolism. α7 Nicotinic Acetylcholine Receptor (α7nAChR) is a key component in the biological functions of acetylcholine. To further explore the health benefits of vagus nerve stimulation, this study aimed to investigate whether α7nAChR agonists offer beneficial effects against poststroke inflammatory and metabolic changes and to identify the underlying mechanisms in a rat model of stroke established by permanent cerebral ischemia. We found evidence showing that pretreatment with α7nAChR agonist, GTS-21, improved poststroke brain infarction size, impaired motor coordination, brain apoptotic caspase 3 activation, dysregulated glucose metabolism, and glutathione reduction. In ischemic cortical tissues and gastrocnemius muscles with GTS-21 pretreatment, macrophages/microglia M1 polarization-associated Tumor Necrosis Factor-α (TNF-α) mRNA, Cluster of Differentiation 68 (CD68) protein, and Inducible Nitric Oxide Synthase (iNOS) protein expression were reduced, while expression of anti-inflammatory cytokine IL-4 mRNA, and levels of M2 polarization-associated CD163 mRNA and protein were increased. In the gastrocnemius muscles, stroke rats showed a reduction in both glutathione content and Akt Serine 473 phosphorylation, as well as an elevation in Insulin Receptor Substrate-1 Serine 307 phosphorylation and Dynamin-Related Protein 1 Serine 616 phosphorylation. GTS-21 reversed poststroke changes in the gastrocnemius muscles. Overall, our findings, provide further evidence supporting the neuroprotective benefits of α7nAChR agonists, and indicate that they may potentially exert anti-inflammatory and metabolic effects peripherally in the skeletal muscle in an acute ischemic stroke animal model.


Assuntos
Lesões Encefálicas , AVC Isquêmico , Acidente Vascular Cerebral , Ratos , Animais , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Acetilcolina , Glucose
4.
Antioxidants (Basel) ; 11(5)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35624826

RESUMO

18ß-Glycyrrhetinic acid is a nutraceutical agent with promising hepatoprotective effects. Its protective mechanisms against cholestatic liver injury were further investigated in a rodent model of extrahepatic cholestasis caused by Bile Duct Ligation (BDL) in rats. The daily oral administration of 18ß-Glycyrrhetinic acid improved liver histology, serum biochemicals, ductular reaction, oxidative stress, inflammation, apoptosis, impaired autophagy, and fibrosis. 18ß-Glycyrrhetinic acid alleviated the BDL-induced hepatic and systemic retention of bile acids, matrix-producing cell activation, hepatic collagen deposition, Transforming Growth Factor beta-1/Smad activation, malondialdehyde elevation, glutathione reduction, High Mobility Group Box-1/Toll-Like Receptor-4 activation, NF-κB activation, inflammatory cell infiltration/accumulation, Interleukin-1ß expression, Signal Transducer and Activator of Transcription-1 activation, Endoplasmic Reticulum stress, impairment autophagy, and caspase 3 activation. Conversely, the protein expression of Sirt1, Farnesoid X Receptor, nuclear NF-E2-Related Factor-2, Transcription Factor EB, bile acid efflux transporters, and LC3-II, as well as the protein phosphorylation of AMP-Activated Protein Kinase, was promoted in 18ß-Glycyrrhetinic acid-treated BDL rats. The hepatoprotective effects of 18ß-Glycyrrhetinic acid in the present investigation correlated well with co-activation and possible interactions among Sirt, FXR, and Nrf2. The concurrent or concomitant activation of Sirt1, FXR, and Nrf2 not only restored the homeostatic regulation of bile acid metabolism, but also alleviated oxidative stress, inflammation, apoptosis, impaired autophagy, and fibrosis.

5.
Biomed Pharmacother ; 151: 113133, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35594710

RESUMO

Plumbagin, a natural bicyclic naphthoquinone, has diverse pharmacological properties and biological benefits against a number of disorders, including liver disease. Though plumbagin's hepatoprotective potential attracts attention, currently no experimental evidence exists on its effectiveness against cholestatic liver injury. The present study investigated its hepatoprotection in the rat model of extrahepatic cholestasis using Bile Duct Ligation (BDL). We found that daily plumbagin supplementation protected the liver from cholestatic damage. Hepatoprotective actions of plumbagin were accompanied by reduction of Transforming Growth Factor ß1 (TGF-ß1)/Smad, High Mobility Group Box-1 (HMGB1)/Toll-Like Receptor-4 (TLR4), Hypoxia-Inducible Factor-1α (HIF-1α), Aryl Hydrocarbon Receptor (AhR), Heat Shock Protein 90 (HSP90), caveolin-1, NF-κB/AP-1, Dynamin Related Protein-1 (Drp1), malondialdehyde level, Interleukin-1ß (IL-1ß), p62/SQSTM1, and caspase 3 as well as increase of Farnesoid X Receptor (FXR), bile acid efflux transporters, glutathione, LC3-II, Beclin1, and nuclear NF-E2-Related Factor-2 (Nrf2) and Transcription Factor EB (TFEB). The activation of nuclear Nrf2 caused by plumbagin correlated well with the improvement in bile acid retention, liver histology, serum biochemical, ductular reaction, mitochondrial dysfunction, oxidative stress, inflammation, apoptosis, impaired autophagy, and fibrosis, involving interplay of multiple intracellular signaling pathways. Plumbagin is likely a candidate drug to protect the liver from cholestatic damages. Despite the promising findings from this study, translational implication of plumbagin on cholestatic liver injury warrants further investigation.


Assuntos
Ductos Biliares , Colestase , Fígado , Naftoquinonas , Animais , Ácidos e Sais Biliares/metabolismo , Ductos Biliares/patologia , Ductos Biliares/cirurgia , Colestase/complicações , Modelos Animais de Doenças , Ligadura , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Naftoquinonas/farmacologia , Naftoquinonas/uso terapêutico , Ratos
6.
Environ Toxicol ; 36(9): 1932-1943, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34165232

RESUMO

Obesity is closely linked with metabolic diseases, while life and prenatal exposure to endocrine-disrupting chemicals has been implicated in the development of obesity. Magnesium lithospermate B (MLB), an active compound of Salvia miltiorrhiza (Danshen), has beneficial effects on insulin resistance and metabolic abnormalities in diet-induced obese rodents. Since exposure to endocrine-disrupting chemical Bisphenol A (BPA) during pregnancy mimics the effects of high fat diet-induced alterations of glucose and lipid metabolism in adult male offspring, the effects of daily MLB supplementation for 4 weeks on metabolic abnormalities in rats weaning from prenatal BPA-exposed dams were investigated. BPA-exposed rats developed obesity and adiposity concurrent with hyperglycemia, hyperinsulinemia, insulin resistance, hypertriglyceridemia, and elevation of circulating glucagon and free fatty acids. Increased hepatic fatty acid synthesis and decreased fatty acid ß-oxidation, activation of adipocytic adipogenesis, maturation, and lipogenesis, as well as reduction of muscular glucose uptake were demonstrated in BPA-exposed rats. The aforementioned alterations were improved by MLB supplementation. Additionally, MLB displayed negative effects on glucocorticoid receptor action and inflammation, and promoted lipolysis and thermogenesis in the adipose tissues. In conclusion, our findings suggest that MLB may be a potential therapeutic compound against metabolic diseases, including maternal exposure-induced metabolic abnormalities.


Assuntos
Compostos Benzidrílicos , Efeitos Tardios da Exposição Pré-Natal , Animais , Compostos Benzidrílicos/toxicidade , Suplementos Nutricionais , Medicamentos de Ervas Chinesas , Feminino , Masculino , Fenóis/toxicidade , Gravidez , Ratos
7.
Nutrients ; 14(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35010979

RESUMO

Magnesium lithospermate B (MLB) is a primary hydrophilic component of Danshen, the dried root of Salvia miltiorrhiza used in traditional medicine, and its beneficial effects on obesity-associated metabolic abnormalities were reported in our previous study. The present study investigated the anti-muscle atrophy potential of MLB in mice with high-fat diet (HFD)-induced obesity. In addition to metabolic abnormalities, the HFD mice had a net loss of skeletal muscle weight and muscle fibers and high levels of muscle-specific ubiquitin E3 ligases, namely the muscle atrophy F-box (MAFbx) and muscle RING finger protein 1 (MuRF-1). MLB supplementation alleviated those health concerns. Parallel changes were revealed in high circulating tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), skeletal TNF receptor I (TNFRI), nuclear factor-kappa light chain enhancer of activated B cells (NF-κB), p65 phosphorylation, and Forkhead box protein O1 (FoxO1) as well as low skeletal phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt) phosphorylation. The study revealed that MLB prevented obesity-associated skeletal muscle atrophy, likely through the inhibition of MAFbx/MuRF-1-mediated muscular degradation. The activation of the PI3K-Akt-FoxO1 pathway and inhibition of the TNF-α/TNFRI/NF-κB pathway were assumed to be beneficial effects of MLB.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Medicamentos de Ervas Chinesas/farmacologia , Atrofia Muscular/induzido quimicamente , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Citocinas/genética , Citocinas/metabolismo , Suplementos Nutricionais , Dislipidemias/tratamento farmacológico , Sequestradores de Radicais Livres/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
8.
Nucleic Acids Res ; 46(D1): D296-D302, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29126174

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs of ∼ 22 nucleotides that are involved in negative regulation of mRNA at the post-transcriptional level. Previously, we developed miRTarBase which provides information about experimentally validated miRNA-target interactions (MTIs). Here, we describe an updated database containing 422 517 curated MTIs from 4076 miRNAs and 23 054 target genes collected from over 8500 articles. The number of MTIs curated by strong evidence has increased ∼1.4-fold since the last update in 2016. In this updated version, target sites validated by reporter assay that are available in the literature can be downloaded. The target site sequence can extract new features for analysis via a machine learning approach which can help to evaluate the performance of miRNA-target prediction tools. Furthermore, different ways of browsing enhance user browsing specific MTIs. With these improvements, miRTarBase serves as more comprehensively annotated, experimentally validated miRNA-target interactions databases in the field of miRNA related research. miRTarBase is available at http://miRTarBase.mbc.nctu.edu.tw/.


Assuntos
Bases de Dados Genéticas , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Mineração de Dados , Humanos , RNA Mensageiro/química , Interface Usuário-Computador
9.
J Neurochem ; 105(1): 151-64, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18067549

RESUMO

Glutamate clearance by astrocytes is critical for controlling excitatory neurotransmission and ATP is an important mediator for neuron-astrocyte interaction. However, the effect of ATP on glutamate clearance has never been examined. Here we report that treatment of RBA-2 cells, a type-2-like astrocyte cell line, with ATP and the P2X(7) receptor selective agonist 3'-O-(4-benzoylbenzoyl) adenosine 5'-triphosphate (BzATP) decreased the Na+-dependent [3H]glutamate uptake within minutes. Mechanistic studies revealed that the decreases were augmented by removal of extracellular Mg2+ or Ca2+, and was restored by P2X7 selective antagonist , periodate-oxidized 2',3'-dialdehyde ATP (oATP), indicating that the decreases were mediated through P2X(7) receptors. Furthermore, stimulation of P2X7 receptors for 2 h inhibited both activity and protein expression of glutamine synthetase (GS), and oATP abolished the inhibition. In addition, removal of extracellular Ca(2+) and inhibition of protein kinase C (PKC) restored the ATP-decreased GS expression but failed to restore the P2X(7)-decreased [3H]glutamate uptake. Therefore, P2X7-mediated intracellular signals play a role in the down-regulation of GS activity/expression. Activation of P2X7 receptors stimulated increases in intracellular Na+ concentration ([Na+](i)) suggesting that the P2X(7)-induced increases in [Na+](i) may affect the local Na+ gradient and decrease the Na+-dependent [3H]glutamate uptake. These findings demonstrate that the P2X7-mediated decreases in glutamate uptake and glutamine synthesis were mediated through distinct mechanisms in these cells.


Assuntos
Astrócitos/metabolismo , Glutamato-Amônia Ligase/metabolismo , Ácido Glutâmico/metabolismo , Receptores Purinérgicos P2/fisiologia , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Sistema X-AG de Transporte de Aminoácidos/genética , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Animais Recém-Nascidos , Astrócitos/efeitos dos fármacos , Benzoxazóis/metabolismo , Cálcio/metabolismo , Células Cultivadas , Córtex Cerebral/citologia , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Compostos de Quinolínio/metabolismo , Ratos , Receptores Purinérgicos P2X7
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