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1.
IUBMB Life ; 71(11): 1740-1750, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31265202

RESUMO

Alcoholic liver disease (ALD) is generated from excessive alcohol consumption, characterized by hepatic steatosis. Mechanistically, excessive hepatic lipid accumulation was attributed to the aberrant lipin-1 signaling during the development of alcoholic steatosis in rodent species and human. Dihydroartemisinin (DHA) has been recently identified to relieve hepatocytes necrosis and prevent from hepatic steatosis in alcohol-induced liver diseases; however, the role of DHA in ALD has not been elucidated completely. Therefore, this study was aimed to further identify the potential mechanisms of pharmacological effects of DHA on ALD. Results demonstrated that DHA regulated the expression and nucleocytoplasmic shuttling of lipin-1 in mice with chronic ethanol exposure. Results confirmed that the disruption of lipin-1 signaling abolished the suppression of DHA on alcohol-induced hepatic steatosis. Interestingly, DHA also significantly improved liver injury, and inflammation mediated by lipin-1 signaling in chronic alcohol-fed mice. in vivo experiments further consolidated the concept that DHA protected against hepatocyte lipoapoptosis dependent on the regulation of nucleocytoplasmic shuttling of lipin-1 signaling, resulting in attenuated ratio of Lpin1 ß/α. Obvious increases in cell apoptosis were observed in alcohol-treated lipin1ß-overexpressed mice. Although DHA attenuated cell apoptosis, overexpression of lipin-1ß neutralized DHA action. DHA ameliorated activation of endoplasmic reticulum stress through inhibiting activation of JNK and CHOP, which was abrogated by overexpression of lipin-1ß. In summary, DHA significantly improved liver injury, steatosis and hepatocyte lipoapoptosis in chronic alcohol-fed mice via regulation of lipin-1 signaling.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Fígado Gorduroso Alcoólico/prevenção & controle , Regulação da Expressão Gênica/efeitos dos fármacos , Fosfatidato Fosfatase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fígado Gorduroso Alcoólico/metabolismo , Fígado Gorduroso Alcoólico/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosfatidato Fosfatase/genética
2.
J Cell Biochem ; 119(2): 2258-2268, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28857294

RESUMO

Angiogenesis of liver sinusoidal endothelial cells (LSECs) accompanies with hypoxia in liver fibrosis and they are of mutual promotion, which has raised wide concern. Here we established murine model of liver fibrosis and found that oroxylin A (40 mg/kg) could ameliorate angiogenesis in liver fibrosis may related to hypoxia inducible factor 1α (HIF-1α). The underlying mechanism was further investigated by isolating and culturing murine primary LSECs. Hypoxia induced vascular endothelial growth factor A (VEGF-A), angiopoietin 2 (Ang-2), and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) elevated in LSECs were reduced by oroxylin A or acriflavine (ACF, an HIF-1α inhibitor), indicating HIF-1α involved the angiogenesis of LSECs. Additionally, interference with Yes-associated protein (YAP) significant downregulated the protein expression of HIF-1α and VEGF-A, while YAP plasmid exhibited an opposite effect. We next found that oroxylin A inhibited hypoxia-induced nuclear translocation of YAP, which may influence the accumulation of HIF-1α and subsequently decrease transcription of downstream target gene including VEGF-A and Ang-2, thereby exerting an anti-angiogenic activity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Flavonoides/administração & dosagem , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Cirrose Hepática/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Fosfoproteínas/metabolismo , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Proteínas de Ciclo Celular , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Masculino , Camundongos , Neovascularização Patológica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Sinalização YAP
3.
Iran J Public Health ; 53(3): 644-653, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38919298

RESUMO

Background: The regulation of p21 in the pyroptosis of cartilage cells still needs to be further clarified. We aimed to explore the regulation of p21 on the pyroptosis of cartilage cells and to reveal the improvement of osteoarthritis. Methods: Chondrocytes were collected and isolated from patients with osteoarthritis (average age 58.64 ± 4.32) in Xuzhou Third People's Hospital, China in 2019, and healthy volunteers (average age 58.23 ± 3.91) were enrolled as the control group. mRNA expression levels of p21 and pyroptosis-related proteins (NLRP3, ASC, total caspase1 and cleaved-Caspase1) were detected by Western blot and real-time PCR. Cell activity, total number of cells and number of dead cells were calculated with CCK-8, MTT. And the regulation of p21 on the pyroptosis of cartilage cells was verified with overexpression and knockdown of p21 in cartilage cells. Results: In cartilage cells of patients with osteoarthritis, the transcription and translation levels of pyrolysis-related genes (NLRP3, cleaved-caspase 1, and ASC) significantly increased (P<0.01). p21 expression was up-regulated and positively correlated with the changing trend of pyrolysis-related proteins (P<0.01). Overexpressing p21 genes in normal cartilage cells significantly increased the expression of pyrolysis-related proteins (P<0.01). Conclusion: The pyroptosis of cartilage cells is causally related to the process of osteoarthritis, and can be regulated by transcription factor p21, which is a potential therapeutic target for osteoarthritis.

4.
Comput Biol Med ; 154: 106606, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36706565

RESUMO

White blood cell (WBC) detection in microscopic images is indispensable in medical diagnostics; however, this work, based on manual checking, is time-consuming, labor-intensive, and easily results in errors. Using object detectors for WBCs with deep convolutional neural networks can be regarded as a feasible solution. In this paper, to improve the examination precision and efficiency, a one-stage and lightweight CNN detector with an attention mechanism for detecting microscopic WBC images, and a white blood cell detection vision system are proposed. The method integrates different optimizing strategies to strengthen the feature extraction capability through the combination of an improved residual convolution module, hybrid spatial pyramid pooling module, improved coordinate attention mechanism, efficient intersection over union (EIOU) loss and Mish activation function. Extensive ablation and contrast experiments on the latest public Raabin-WBC dataset verify the effectiveness and robustness of the proposed detector for achieving a better overall detection performance. It is also more efficient than other existing studies for blood cell detection on two additional classic public BCCD and LISC datasets. The novel detection approach is significant and flexible for medical technicians to use for blood cell microscopic examination in clinical practice.


Assuntos
Trabalho de Parto , Leucócitos , Gravidez , Feminino , Humanos , Microscopia , Redes Neurais de Computação
5.
Plants (Basel) ; 12(16)2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37631212

RESUMO

Oryza officinalis Wall is a potential genetic resource for rice breeding; however, its distant genome limits its crossing ability with cultivated rice. The interspecific hybridization of O. officinalis and cultivated rice, establishment of its tissue culture, and induction of polyploidy are ways to improve O. officinalis's poor crossability. We developed an interspecific hybrid and studied its reproductive pollen development process in this work, and the results showed that abortive pollens (81.94%) and embryo sac abnormalities (91.04%) were the key causes of its high sterility. In order to induce callus formation in interspecific hybrid explants, two different culture media, namely Chu's N-6 medium (N6) and 1/2 Murashig and Skoog medium (1/2 MS), were employed. Additionally, two plant growth regulators (PGRs), namely 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BA), along with L-proline (Pro) and acid hydrolyzed casein, were utilized in the experiment. The optimal N6 medium, supplemented with 2.0 mg·L-1 2,4-D, produced the highest induction rate (80.56 ± 5.44)%. For callus differentiation and proliferation, the MS medium supplemented with 2.0 mg·L-1 BA + 0.2 mg·L-1 NAA produced the highest differentiation rate (75.00 ± 4.97)% and seedling emergence ratio (28.97 ± 4.67)%. The optimal combination for seedling rooting was the 1/2 MS medium supplemented with 2.0 mg L-1 NAA and 0.2 mg L-1 BA, which produced an average of 13.95 roots per plant. For polyploidy induction in the interspecific hybrid, the concentration of colchicine treatment at 400 mg·L-1 for three days is an ideal protocol. We devised tissue culture and interspecific hybrid polyploidy induction to overcome O. officinalis' poor crossability and introduce its favorable features into cultivated rice.

6.
R Soc Open Sci ; 9(10): 211927, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36249339

RESUMO

Traditional contact tracing tests the direct contacts of those who test positive. But, by the time an infected individual is tested, the infection starting from the person may have infected a chain of individuals. Hence, why should the testing stop at direct contacts, and not test secondary, tertiary contacts or even contacts further down? One deterrent in testing long chains of individuals right away may be that it substantially increases the testing load, or does it? We investigate the costs and benefits of such multi-hop contact tracing for different number of hops. Considering diverse contact networks, we show that the cost-benefit trade-off can be characterized in terms of a single measurable attribute, the initial epidemic growth rate. Once this growth rate crosses a threshold, multi-hop contact tracing substantially reduces the outbreak size compared with traditional tracing. Multi-hop even incurs a lower cost compared with the traditional tracing for a large range of values of the growth rate. The cost-benefit trade-offs can be classified into three phases depending on the value of the growth rate. The need for choosing a larger number of hops becomes greater as the growth rate increases or the environment becomes less conducive toward containing the disease.

7.
Comput Methods Programs Biomed ; 221: 106888, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35598435

RESUMO

BACKGROUND AND OBJECTIVE: At present, the COVID-19 epidemic is still spreading worldwide and wearing a mask in public areas is an effective way to prevent the spread of the respiratory virus. Although there are many deep learning methods used for detecting the face masks, there are few lightweight detectors having a good effect on small or medium-size face masks detection in the complicated environments. METHODS: In this work we propose an efficient and lightweight detection method based on YOLOv4-tiny, and a face mask detection and monitoring system for mask wearing status. Two feasible improvement strategies, network structure optimization and K-means++ clustering algorithm, are utilized for improving the detection accuracy on the premise of ensuring the real-time face masks recognition. Particularly, the improved residual module and cross fusion module are designed to aim at extracting the features of small or medium-size targets effectively. Moreover, the enhanced dual attention mechanism and the improved spatial pyramid pooling module are employed for merging sufficiently the deep and shallow semantic information and expanding the receptive field. Afterwards, the detection accuracy is compensated through the combination of activation functions. Finally, the depthwise separable convolution module is used to reduce the quantity of parameters and improve the detection efficiency. Our proposed detector is evaluated on a public face mask dataset, and an ablation experiment is also provided to verify the effectiveness of our proposed model, which is compared with the state-of-the-art (SOTA) models as well. RESULTS: Our proposed detector increases the AP (average precision) values in each category of the public face mask dataset compared with the original YOLOv4-tiny. The mAP (mean average precision) is improved by 4.56% and the speed reaches 92.81 FPS. Meanwhile, the quantity of parameters and the FLOPs (floating-point operations) are reduced by 1/3, 16.48%, respectively. CONCLUSIONS: The proposed detector achieves better overall detection performance compared with other SOTA detectors for real-time mask detection, demonstrated the superiority with both theoretical value and practical significance. The developed system also brings greater flexibility to the application of face mask detection in hospitals, campuses, communities, etc.


Assuntos
COVID-19 , Algoritmos , Humanos , Máscaras , Pandemias/prevenção & controle
8.
Eur J Med Chem ; 235: 114258, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35339101

RESUMO

Combinational utilization of intravenous non-steroidal anti-inflammatory drugs (NSAIDs) with opium analgesic is an effective alternative modality for pain control after surgery. This regimen is known for reducing the risk of addiction induced by opium analgesic. However, current intravenous NSAIDs have solubility problems, limiting their clinical applications. Although loxoprofen exhibits strong anti-inflammatory and analgesic activities with relatively low ulcerogenicity, its relatively low bioavailability makes it not an ideal drug candidate for intravenous injection. We selected the bioactive metabolite (6) of loxoprofen as a candidate and developed a new intravenous NSAID, HR1405-01. This metabolite exhibited significantly stronger anti-inflammatory and analgesic activities than parecoxib sodium injection or ibuprofen injection. The excellent potency and solubility of HR1405-01 allowed the avoidance of utilization of cosolvent in the formulation, resulting in fewer side effects and a better safety profile. Therefore, HR1405-01 might be a promising candidate for the development of a new intravenous NSAID.


Assuntos
Anti-Inflamatórios não Esteroides , Ópio , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores de Ciclo-Oxigenase , Ibuprofeno
9.
Biomed Pharmacother ; 97: 975-984, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29136776

RESUMO

Alcoholic liver disease (ALD), characterized by accumulation of fatty acids in liver cells, is usually caused by Chronic alcohol consumption. Our previous study has identified that DA protects against alcoholic liver injury in alcohol-fed rats through alleviating hepatocyte steatosis. It has emerged that saturated fatty acids could provoke endoplasmic reticulum (ER) stress and apoptosis in hepatocytes. This study was aimed to explore the impact of DA on ALD and further elaborate the underlying mechanisms. Results demonstrated that DA attenuates alcoholic liver injury in mice. Our results also indicated that DA attenuated lipid accumulation in hepatocytes exposed to ethanol. DA attenuates ethanol-induced hepatocyte apoptosis. Results demonstrated that DA dose-dependently ameliorated activation of mitochondrial pathway activation, which plays a critical role in apoptosis attributed to lipotoxicity. Further, DA suppressed the activation of JNK and the expression of CHOP, attributed to the inhibition of ER stress. It has emerged that activation of ER stress-JNK/CHOP-mitochondria cascade is considered as the key mechanisms underlying hepatocyte lipoapoptosis. In addition, DA attenuates PI3K/Akt Pathway in hepatocytes, consistent with our previous finding in HSCs. DA effects were reinforced by PI3K specific inhibitor LY294002. In summary, DA significantly protected hepatocytes against lipoapoptosis via a PI3K/Akt Pathway inhibition-dependent mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Animais , Cromonas/farmacologia , Etanol/toxicidade , Hepatócitos/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Hepatopatias Alcoólicas/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
10.
Chem Biol Interact ; 285: 14-20, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29476730

RESUMO

Accumulating data reveal that oroxylin A has beneficial effects against chronic liver disease. The previously studies showed oroxylin A, a flavonoid extracted from Scutellariae radix, improved acute liver injury and accelerated liver regeneration in vivo. However, it's unclear that the effect of oroxylin A on alcoholic liver disease. The present study was aimed at elucidating the effect of oroxylin A on alcohol-induced hepatic steatosis and the underlying mechanisms. Human hepatocyte LO2 were cultured and stimulated with ethanol for inducing LO2 damage. We examined the effects of oroxylin A on the accumulation of lipid droplets in ethanol-treated LO2. The results showed that oroxylin A reduced the accumulation of lipid droplets associated with regulating the lipid metabolism genes. Moreover, oroxylin A significantly suppressed the nuclear translocation of HIF-1α in ethanol-treated LO2. Furthermore, activation of HIF-1α significantly attenuated the effect of oroxylin A on lipid droplets accumulation and genes related to lipid metabolism in vitro and in vivo. Altogether, we demonstrated a HIF-1α-associated mechanism underlying oroxylin A inhibition of lipid deposition in ethanol-stimulated LO2. Oroxylin A modulation of HIF-1α level may represent a therapeutic remedy for ALD.


Assuntos
Etanol/toxicidade , Flavonoides/farmacologia , Hepatócitos/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Células Cultivadas , Fígado Gorduroso/prevenção & controle , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Extratos Vegetais/farmacologia
11.
Cell Prolif ; 51(3): e12431, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29318697

RESUMO

OBJECTIVES: Oroxylin A, a natural flavonoid isolated from Scutellaria baicalensis, has been reported to have anti-hepatic injury effects. However, the effects of oroxylin A on alcoholic liver disease (ALD) remains unclear. The aim of this study was to elucidate the effects of oroxylin A on ALD and the potential mechanisms. MATERIALS AND METHODS: Male ICR mice and human hepatocyte cell line LO2 were used. Yes-associated protein (YAP) overexpression and knockdown were achieved using plasmid and siRNA technique. Cellular senescence was assessed by analyses of the senescence-associated ß-galactosidase (SA-ß-gal), senescence marker p16, p21, Hmga1, cell cycle and telomerase activity. RESULTS: Oroxylin A alleviated ethanol-induced hepatocyte damage by suppressing activities of supernatant marker enzymes. We found that oroxylin A inhibited ethanol-induced hepatocyte senescence by decreasing the number of SA-ß-gal-positive LO2 cells and reducing the expression of senescence markers p16, p21 and Hmga1 in vitro. Moreover, oroxylin A affected the cell cycle and telomerase activity. Of importance, we revealed that YAP pharmacological inhibitor verteporfin or YAP siRNA eliminated the effect of oroxylin A on ethanol-induced hepatocyte senescence in vitro, and this was further supported by the evidence in vivo experiments. CONCLUSION: Therefore, these aggregated data suggested that oroxylin A relieved alcoholic liver injury possibly by inhibiting the senescence of hepatocyte, which was dependent on its activation of YAP in hepatocytes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Senescência Celular/efeitos dos fármacos , Etanol/toxicidade , Flavonoides/farmacologia , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Expressão Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Humanos , Fígado/patologia , Hepatopatias Alcoólicas/tratamento farmacológico , Masculino , Camundongos Endogâmicos ICR , Fosfoproteínas/genética , Transdução de Sinais , Fatores de Transcrição , Proteínas de Sinalização YAP
12.
Biofactors ; 43(6): 836-846, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29048780

RESUMO

Varied pathogenetic elements have been touched upon the liver fibrosis, including inflammatory, stress, apoptosis and unfolded proteins aggregation. Magnesium Isoglycyrrhizinate (MgIG) has been accepted to be a neuroprotective effect, hepatoprotective and anti-inflammatory molecule. In our vitro researches, MgIG was considered to activate hepatic stellate cells (HSCs) apoptosis by promoting endoplasmic reticulum stress (ERS) detrimental response to a certain extent. Consequently, MgIG showed its potential therapeutic capacity in fibrogenesis and counteracted the pathogenetic aspects, which were involved in integrating current treatments correcting liver fibrosis. In addition, we further verificated the behavior and pathogenic mechanisms in the CCl4 -induced liver fibrosis in male mice. What surprised us was that with the treatment of MgIG caused the activation of ERS and resisted the activated HSCs in the protective effects on liver damage. We found MgIG significantly promoted the apoptosis of activated HSCs and protected the CCl4 -induced liver fibrosis. Main molecules came down to the unfolded protein response signaling pathway. Furthermore, MgIG inhibited the levels of the downstream inflammatory cytokines, which were triggered by CCl4 -induced liver fibrosis. Here, we reported that MgIG improved behavioral impairments induced by intraperitoneal injection of CCl4 and decreased the expression of proinflammatory factor, which indicated the preserving effects on liver fibrosis. © 2017 BioFactors, 43(6):836-846, 2017.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Apoptose/genética , Tetracloreto de Carbono , Linhagem Celular , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclina E/genética , Ciclina E/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Regulação da Expressão Gênica , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Transdução de Sinais , Resposta a Proteínas não Dobradas/efeitos dos fármacos , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
13.
Eur J Pharm Sci ; 96: 323-333, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27717875

RESUMO

Accumulating evidence indicates that hepatic stellate cells (HSCs) are the central mediators and major effectors in the development of hepatic fibrosis. It is well-known that regulation of cell proliferation and apoptosis are potential strategies to block the activation of HSCs. Recently, several studies have revealed that induction of HSC senescence could prevent and cure the liver fibrosis. In our previous work, we have demonstrated that the natural product tetramethylpyrazine (TMP) could inhibit the activation of HSCs and ameliorate hepatic fibrosis. The aim of this study was to identify a new role of TMP in the regulation of activated HSC senescence and to elucidate the underlying mechanisms. In this study, our data showed that TMP could promote HSC senescence in vivo and in vitro. Moreover, TMP affected the cell cycle and telomerase activity. We further demonstrated that P53 siRNA or P53 pharmacological inhibitor PFT-α abrogated the TMP-induced HSC senescence in vitro. Meanwhile, similar results were obtained in vivo. Further studies indicated that TMP promoted the expression of P53 through a YAP inhibition-dependent mechanism. Moreover, silencing YAP enhanced TMP induction of activated HSC senescence. Collectively, our results suggested that TMP inhibited the activation of HSCs by inducing senescence and had therapeutic implication for the treatment of liver fibrosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Senescência Celular/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Fosfoproteínas/antagonistas & inibidores , Pirazinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/fisiologia , Proteínas de Ciclo Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Senescência Celular/fisiologia , Células Estreladas do Fígado/fisiologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosfoproteínas/fisiologia , Pirazinas/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Proteínas de Sinalização YAP
14.
Cell Signal ; 33: 79-85, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28188823

RESUMO

Hepatic fibrosis, a common scarring response to various forms of chronic liver injury, is a precursor to cirrhosis and liver cancer. During liver fibrosis, hepatic stellate cells (HSCs) initially activate and proliferate, which are responsible for the secretion of extracellular matrix components. However, these cells eventually senesce and are cleared by natural killer (NK) cells. Our previous researches have shown that the natural product curcumin could promote the senescence of activated HSC. In this study, we investigated how NK cells target senescent HSC and assessed the effect of this process on liver fibrosis. We found that senescent HSC induced by curcumin are susceptible to NK cells killing, due to the increased expression of NK cell activating ligand major histocompatibility complex class I chain-related genes A (MICA) and UL16-binding proteins 2 (ULBP2), but not Poliovirus Receptor (PVR). Further studies displayed that the interaction between NK cells and senescent LX2 cells stimulated granule exocytosis. Moreover, the inhibition of granule exocytosis weakened the cytotoxicity of NK cells and promoted the accumulation of senescent LX2 cells. Therefore, these aggregated data indicated that NK cells mediated clearance of senescent LX2 cells and granule exocytosis could play a protective role in the improvement of liver fibrosis.


Assuntos
Senescência Celular/efeitos dos fármacos , Curcumina/farmacologia , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Células Matadoras Naturais/metabolismo , Cirrose Hepática/patologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Exocitose/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/metabolismo , Masculino , Camundongos Endogâmicos ICR
15.
Int J Rheum Dis ; 18(1): 3-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24751105

RESUMO

OBJECTIVES: The objective of the present meta-analysis was to investigate whether the combined evidence shows an association between the STAT4 rs7574865 polymorphism and RA. METHODS: A systematic search of all relevant studies published through April 2013 was conducted using MEDLINE, EMBASE, OVID, and ScienceDirect. The observational studies that were related to an association between the STAT4 rs7574865 polymorphism and RA were identified. The association between the STAT4 rs7574865 polymorphism and RA susceptibility was assessed using genetic models. RESULTS: Seventeen case-control studies with a total of 28 comparisons (25 300 RA patients and 26 326 controls) met the inclusion criteria. A meta-analysis was conducted for genotype TT versus GT+GG, GT+TT versus GG, TT versus GG and T-allele. The meta-analysis showed an association between RA and the STAT4 rs7574865 TT genotype, GT+TT genotype and T-allele in all subjects. Stratification of RA patients according to ethnic group showed that the TT genotype, GT+TT genotype and T-allele were significantly associated with RA in Europeans, Asians, Africans and Latin Americans. A subgroup analysis according to the absence or presence of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies revealed that the association between the STAT4 rs7574865 polymorphism and RA may be independent of the presence of RF and anti-CCP antibodies. CONCLUSIONS: This meta-analysis demonstrated that the STAT4 rs7574865 polymorphism confers susceptibility to RA in major ethnic groups. The association may not be dependent on the presence of RF and anti-CCP antibodies.


Assuntos
Artrite Reumatoide/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/etnologia , Biomarcadores/sangue , Estudos de Casos e Controles , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Razão de Chances , Peptídeos Cíclicos/sangue , Fenótipo , Fator Reumatoide/sangue , Fatores de Risco
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