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1.
Dig Dis Sci ; 69(2): 476-490, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38170336

RESUMO

BACKGROUND: Cholangiocarcinoma (CCA) is a malignant tumor with a high mortality rate. Resistance to chemotherapy remains a major challenge related to cancer treatment, and increasing the sensitivity of cancer cells to therapeutic drugs is a major focus of cancer treatment. AIMS: We purposed to explore the role of Metformin in CCA involved in chemotherapeutic sensitivity and Pyruvate kinase M2 (PKM2) through regulating mitochondrial apoptosis in the present study. METHODS: CCA cell lines of HCC9810 and RBE were treated with Metformin companied with antagonists or agonists of PKM2, cells sensitivity to Gemcitabine, cell migration and invasion along with apoptosis, which is mediated by JC-1 and LDH were assayed. RESULTS: Our results indicated that Metformin and Gemcitabine exhibit synergistic effect on inhibition of cholangiocarcinoma cell viability, cell migration and invasion as well as promotion apoptosis of cholangiocarcinoma cells. In vivo, Metformin combined with Gemcitabine has cooperation in inhibiting the growth of cholangiocarcinoma cell-derived tumors. Moreover, Metformin and Gemcitabine inhibited expression of PKM2 and PDHB in HCC9810 and RBE. CONCLUSION: Our study suggested that Metformin may increase the response of cholangiocarcinoma cells to Gemcitabine by suppressing PKM2 to activate mitochondrial apoptosis.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Metformina , Humanos , Gencitabina , Metformina/farmacologia , Metformina/uso terapêutico , Piruvato Quinase/farmacologia , Piruvato Quinase/uso terapêutico , Linhagem Celular Tumoral , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Apoptose , Ductos Biliares Intra-Hepáticos/patologia , Proliferação de Células
2.
J Environ Manage ; 356: 120643, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38513582

RESUMO

Hydrothermal aqueous phase (HAP) contains abundant organics and nutrients, which have potential to partially replace chemical fertilizers for enhancing plant growth and soil quality. However, the underlying reasons for low available nitrogen (N) and high N loss in dryland soil remain unclear. A cultivation experiment was conducted using HAP or urea to supply 160 mg N kg-1 in dryland soil. The dynamic changes of soil organic matters (SOMs), pH, N forms, and N cycling genes were investigated. Results showed that SOMs from HAP stimulated urease activity and ureC, which enhanced ammonification in turn. The high-molecular-weight SOMs relatively increased during 5-30 d and then biodegraded during 30-90 d, which SUV254 changed from 0.51 to 1.47 to 0.29 L-1 m-1. This affected ureC that changed from 5.58 to 5.34 to 5.75 lg copies g-1. Relative to urea, addition HAP enhanced ON mineralization by 8.40 times during 30-90 d due to higher ureC. It decreased NO3-N by 65.35%-77.32% but increased AOB and AOA by 0.25 and 0.90 lg copies g-1 at 5 d and 90 d, respectively. It little affected nirK and increased nosZ by 0.41 lg copies g-1 at 90 d. It increased N loss by 4.59 times. The soil pH for HAP was higher than that for urea after 11 d. The comprehensive effects of high SOMs and pH, including ammonification enhancement and nitrification activity inhibition, were the primary causes of high N loss. The core idea for developing high-efficiency HAP fertilizer is to moderately inhibit ammonification and promote nitrification.


Assuntos
Fertilizantes , Solo , Nitrogênio/metabolismo , Microbiologia do Solo , Amônia , Nitrificação , Ureia
3.
Opt Express ; 31(23): 38004-38012, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017918

RESUMO

We investigate the orbital angular momentum (OAM) flux density of beams which are the incoherent superposition of partially coherent vortex (PCV) beams with different topological charges and beam widths. Simulation results show that such beams can exhibit counter-rotating radial regions of the OAM flux density, and that we can "switch" the order of these regions by adjusting the topological charges and beam widths in the source plane. Furthermore, these counter-rotating regions can switch on propagation in free space without any change to the beam parameters. We discuss how these unusual OAM dynamics may find use in OAM-based applications.

4.
Opt Lett ; 48(3): 558-561, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723530

RESUMO

A simple expression for the correlations of beams radiated by Schell-model sources carrying a prescribed astigmatic phase (cross phase) in 3D space is derived. The z-coherence of such sources upon free-space propagation is investigated in detail. It is demonstrated that the z-coherence does not decrease to zero with an increasing separation of two axial points. Our results show that the initial cross phase, coherence, and correlation state of such sources affect the distribution of the z-coherence. Furthermore, the cross phase plays a role in maintaining z-coherence, which will be useful in applications where high z-coherence is required.

5.
Environ Microbiol ; 24(9): 4013-4029, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35466499

RESUMO

The outbreak of the COVID-19 epidemic is a reminder that aerosols have important health effects as a potential route for disease transmission. Biological components in aerosols (especially PM2.5 ) may pose potential threats to humans as pathogens and allergens. Research on PM2.5 and biological components currently focuses mainly on polluted conditions, with less emphasis on clean environments. Sampling has also been primarily based on a single point with a lack of data at different positions. In this study, a modified fluorescein diacetate hydrolysis method was used to measure microbial activity in PM2.5 at different altitudes over a year in Beijing, China. A high-throughput sequencing method was used to study the microbial community. Results showed that microbial activity 1.5 m (0.0465 ng m-3 ) above the ground was higher than 31.5 m (0.0348 ng m-3 ). There was higher microbial activity at both heights during spring. Furthermore, a positive correlation was observed between microbial activity and relative abundance of dominant species. Microbial activity increased during autumn and winter increased alongside the pollution level, but in spring higher levels of microbial activity were observed in excellent or good weather conditions. The results from this study are valuable for further research regarding the biological components of atmospheric PM, the prevention of biological pollution, and establishing a comprehensive air quality evaluation system.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Alérgenos , Atmosfera , Pequim , China , Monitoramento Ambiental/métodos , Humanos , Material Particulado/análise , Aerossóis e Gotículas Respiratórios , Estações do Ano
6.
Proc Natl Acad Sci U S A ; 116(31): 15407-15413, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31315978

RESUMO

Centrality is widely recognized as one of the most critical measures to provide insight into the structure and function of complex networks. While various centrality measures have been proposed for single-layer networks, a general framework for studying centrality in multilayer networks (i.e., multicentrality) is still lacking. In this study, a tensor-based framework is introduced to study eigenvector multicentrality, which enables the quantification of the impact of interlayer influence on multicentrality, providing a systematic way to describe how multicentrality propagates across different layers. This framework can leverage prior knowledge about the interplay among layers to better characterize multicentrality for varying scenarios. Two interesting cases are presented to illustrate how to model multilayer influence by choosing appropriate functions of interlayer influence and design algorithms to calculate eigenvector multicentrality. This framework is applied to analyze several empirical multilayer networks, and the results corroborate that it can quantify the influence among layers and multicentrality of nodes effectively.

7.
J Environ Manage ; 323: 116307, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36261995

RESUMO

Process water (PW) obtained from hydrothermal carbonization of nitrogen-rich (N-rich) biowaste is proposed to be a renewable resource utilized as a liquid N fertilizer. However, its effects on soil microbial community, N transformation, and plant N uptake are unclear or controversial. In this study, fertilizers were prepared with different percentages of PW (poultry litter, 220 °C 1 or 8 h, PW-S or -L) and urea to supply 160 mg kg-1 total N in a barren alkali soil. Results showed that the addition of PW relative to pure urea decreased organic N mineralization by low bio-accessibility, increased N loss by high soil pH, and decreased NO3--N by low nitrification substrate. It supported the lettuce in health but decreased plant N uptake by low NO3--N. It significantly increased the gram-positive bacteria that responded to resistant organic matter, changed the bacterial community to enhance decomposition, detoxification, ureolysis, and denitrification, and to decrease nitrification. Its inhibition effect on nitrification activity was stronger than that on nitrifiers growth. Different from PW-S, the addition of PW-L seriously and significantly decreased seed germination index and fungal biomass that responded to N retaining capacity, respectively. The best fertilizer was 50% urea +50% PW-S that supported the seed germination and seedling growth, and mildly affected microbial community.


Assuntos
Microbiota , Solo , Animais , Solo/química , Fertilizantes/análise , Nitrogênio/análise , Água , Aves Domésticas , Ureia
8.
Indian Pacing Electrophysiol J ; 22(5): 231-234, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35926684

RESUMO

BACKGROUND: Axillary vein puncture is a popular puncture site for pacemaker implantation. However, due to the lacking of body surface markers, the current puncture method is too complicated and affect the popularization and application of axillary vein puncture. Here, we performed a new body surface landmark to make the blind axillary vein puncture simple and easy. METHODS: The study population included 30 patients referred for pacemaker implantation using axillary vein puncture. Digital subtraction angiography (DSA) was used to determine the direction and the surface landmarks of the axillary vein. Medial cusp of thoracic triangle and the coracoid process were directly touched with fingers. The puncture point was about 1 cm below the coracoid, and the needle tip pointed to the medial cusp of thoracic triangle with the angle of 30-60°. RESULTS: There was little variation in distribution of axillary vein. The body surface landmark of the junction of the axillary vein and the subclavian vein is on the medial cusp of thoracic triangle. In these 30 patients, blind axillary vein puncture was successful obtained in all patients. There was no pneumothorax and inadvertent arterial puncture. The pacemaker lead wire was placed smoothly. Moreover, the pacemaker pocket was ideally positioned when cut along the puncture point. CONCLUSIONS: Blind axillary vein access using the body surface landmark of the thoracic triangle is an effective method for pacemaker implantation and can obvious avoid the complications usually observed with the traditional subclavian vein approach.

9.
Ecotoxicol Environ Saf ; 224: 112652, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34461319

RESUMO

Polychlorinated biphenyls (PCBs) are synthetic biphenyl compounds with high toxicity. There are a total of 209 homologs, among which 2,3',4,4',5-pentachlorobiphenyl (PCB118) is one of the dioxin-like PCBs. PCB118 can accumulate in pregnant mice, leading to fetus directly exposure during development. The stage of migration of mouse primordial germ cells ranges from 8.5 to 13.5 days of pregnancy, which is the stage undergoing a genome-wide DNA demethylation process. In this study, the mice were exposed to 20 µg/kg/day and 100 µg/kg/day PCB118 from 8.5 to 13.5 days of pregnancy. During the embryo stage at 18.5 days (E18.5 days), the expression level of DNA methyltransferase 1 (Dnmt1) was reduced in the testes, and the DNA methylation level in mouse testes were also decreased. We found that the seminiferous tubules showed vacuolization and that the sperm deformity rate increased in the treated groups compared with the control group in 7-week-old mice. Because exposure to PCB118 during pregnancy causes damage to the reproductive system of male offspring mice, attention should be devoted to the toxicity transmission of persistent environmental pollutants such as PCBs.

10.
Reprod Fertil Dev ; 32(12): 1048-1059, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32758352

RESUMO

Polychlorinated biphenyls (PCBs) are persistent organic pollutants, and the widespread use of PCBs has had adverse effects on human and animal health. This study experiment explored the effects of 2,3',4,4',5-pentachlorobiphenyl (PCB118) on the mammalian reproductive system. PCB118 was administered to pregnant mice from 7.5 to 12.5 days of gestation; F1 mice were obtained and the reproductive system of F1 male mice was examined. PCB118 damaged the reproductive system in male F1 mice, as evidenced by negative effects on the testicular organ coefficient (testes weight/bodyweight), a decrease in the diameter of seminiferous tubules and a significant reduction in the anogenital distance in 35-day-old F1 mice. In addition, methylation levels of genomic DNA were reduced, with reductions in the expression of the DNA methyltransferases DNMT1, DNMT3A and DNMT3B, as well as that of the epigenetic regulatory factor ubiquitin like with PHD and ring finger domains 1 (Uhrf1). Together, the results of this study provide compelling evidence that exposure of pregnant mice to PCB118 during primordial germ cell migration in the fetus affects the reproductive system of the offspring and decreases global methylation levels in the testis.


Assuntos
Metilação de DNA/efeitos dos fármacos , Bifenilos Policlorados/farmacologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Testículo/efeitos dos fármacos , Animais , Feminino , Masculino , Exposição Materna/efeitos adversos , Camundongos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Testículo/metabolismo
11.
Biosci Biotechnol Biochem ; 84(4): 714-724, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31797747

RESUMO

Heart failure (HF) is one of the most severe heart conditions, which lacks effective therapies. Therefore, it is necessary to develop more efficient drugs for HF. In this study, we investigated the cardioprotective effects of hyperoside against the pathological progression of HF. Thoracic aortic constriction (TAC) was performed to induce HF in rats. Hyperoside treatment improved cardiac function, decreased cardiomyocyte cross-sectional area and heart weight to body weight (HW/BW) ratio in HF rats. Moreover, hyperoside administration repressed apoptosis as evidenced by changing apoptosis-related protein levels, and promoted autophagy in TAC rats and angiotensin II (AngII)-induced H9C2 cells. Inhibition of autophagy by 3-methyladenine (3-MA) attenuated the beneficial effect of hyperoside against apoptosis in H9C2 cells. In summary, these data confirm that hyperoside effectively alleviates HF via suppressing apoptosis and inducing autophagy, which provides evidence that hyperoside may serve as a promising natural drug for treating HF.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Cardiotônicos/farmacologia , Insuficiência Cardíaca/prevenção & controle , Miocárdio/patologia , Quercetina/análogos & derivados , Angiotensina II/farmacologia , Animais , Células Cultivadas , Masculino , Quercetina/farmacologia , Ratos , Ratos Wistar
12.
J Appl Toxicol ; 40(10): 1396-1409, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32418265

RESUMO

Polychlorinated biphenyls (PCBs) are a class of persistent organic environmental pollutants with a total of 209 homologs. The homolog 2,3',4,4',5-pentachlorobiphenyl (PCB118) is one of the most important dioxin-like PCBs and is highly toxic. PCB118 can accumulate in human tissues, serum and breast milk, which leads to direct exposure of the fetus during development. In the present study, pregnant mice were exposed to 0, 20 and 100 µg/kg/day of PCB118 during the stage of fetal primordial germ cell migration. Compared with the control group, we found morphological alterations of the seminiferous tubules and a higher sperm deformity rate in the male offspring in the treatment groups. Furthermore, the methylation patterns in the treatment groups of the imprinted genes H19 and Gtl2 in the sperm were altered in the male offspring. We also characterized the disturbance of the expression levels of DNA methyltransferase 1 (Dnmt1), Dnmt3a, Dnmt3b, Dnmt3l, and Uhrf1. The results indicated that intrauterine exposure to low doses of PCB118 could significantly damage the reproductive health of the male offspring. Therefore, attention should be paid to the adverse effects of PCB118 exposure during pregnancy on the reproductive system of male offspring.


Assuntos
Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Genitália/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Espermatozoides/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Feminino , Masculino , Exposição Materna/efeitos adversos , Camundongos , Modelos Animais , Gravidez
13.
World J Surg Oncol ; 18(1): 83, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357945

RESUMO

BACKGROUND: Osteosarcoma (OS) is a primary malignant bone tumor with a high rate of metastasis and a short 5-year survival rate. MiR-363 was downregulated in a variety of tumors and played a role in suppressing tumors. However, the roles of miR-363 in osteosarcoma remain unknown; thus, the purpose of this study was to explore the functions of miR-363 in osteosarcoma. METHODS: CCK-8 and transwell assays were performed to evaluate the proliferation, migration, and invasion abilities of MG63 cells. The epithelial-mesenchymal transition (EMT) and apoptosis-associated proteins were measured by using Western blot assay. Luciferase reporter assay was utilized to verify whether miR-363 directly bound to the 3'-UTR of NOB1 mRNA. RESULTS: MiR-363 was downregulated while NOB1 was upregulated in osteosarcoma clinical tissue specimens and cell lines as compared with the adjacent normal tissue specimens and normal cell line. The miR-363 is reversely correlated with the expression of NOB1 in osteosarcoma tissues. Overexpression of miR-363 suppressed the ability of cell migration, invasion, and EMT, whereas low expression of miR-363 promoted this ability. In addition, miR-363 inhibited osteosarcoma proliferation both in vitro and in vivo and inhibited the apoptosis in MG63 cells. Interference of NOB1 could inhibit the migration, invasion, and EMT of osteosarcoma cell line MG63. NOB1 was verified to be a direct target of miR-363 and its expression was mediated by miR-363. Re-expression of NOB1 could partially reverse the inhibitory effect of miR-363 on cell migration and invasion. In addition, low expression of miR-363 or overexpression of NOB1 predicted poor prognosis of osteosarcoma patients. CONCLUSION: MiR-363 inhibited osteosarcoma the proliferation, migration, invasion, and EMT and induced the apoptosis by directly targeting NOB1 in MG63 cells. The newly identified miR-363/NOB1 axis provides novel insights into the pathogenesis of osteosarcoma.


Assuntos
Neoplasias Ósseas/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Proteínas Nucleares/genética , Osteossarcoma/genética , Proteínas de Ligação a RNA/genética , Regiões 3' não Traduzidas/genética , Adolescente , Apoptose/genética , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Osso e Ossos/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Masculino , MicroRNAs/genética , Invasividade Neoplásica/genética , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
14.
J Hand Surg Am ; 45(2): 161.e1-161.e6, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31153656

RESUMO

Synovial hemangiomas (SHs) are rare lesions of the joints or tendon sheaths that are difficult to diagnose. We present the case of an 18-year-old man with an SH in the wrist joint. Physical examination revealed a slightly tender, ill-defined, nonpulsatile soft mass, 3 cm × 3 cm in size on the dorsal aspect of the left wrist. Computed tomography showed an irregular, ill-defined, soft tissue mass in the expanded joint space, which was formed by the scaphoid, trapezoid, and capitate bones. Magnetic resonance imaging showed the typical features of SH and also revealed cavitary erosion of the scaphoid, trapezoid, and capitate bones. An open arthrotomy was performed via a dorsal approach, and the mass was excised. The histological examination findings were consistent with the diagnosis of SH.


Assuntos
Capitato , Ossos do Carpo , Hemangioma , Artropatias , Adolescente , Capitato/diagnóstico por imagem , Capitato/cirurgia , Hemangioma/diagnóstico por imagem , Hemangioma/cirurgia , Humanos , Masculino , Punho , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/cirurgia
15.
Opt Lett ; 44(15): 3617-3620, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368926

RESUMO

We investigate the orbital angular momentum of partially coherent beams which are constructed by a superposition of mutually incoherent vortex modes, each mode having a different beam width and topological charge. It is shown that these simple beams nevertheless provide great flexibility in controlling orbital angular momentum through adjustment of the beam parameters and have significant potential for particle rotation and trapping.

16.
Can J Physiol Pharmacol ; 97(11): 1028-1034, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31330113

RESUMO

Brd4 protein is an important epigenetic regulator involved in the process of inflammatory cytokine production in many diseases. However, whether and how Brd4 participates in the process of wear-particle-induced inflammation remain unclear. This study aimed to investigate the potential role of Brd4 in titanium (Ti) particle-induced inflammatory cytokine production in mouse macrophage RAW264.7 cells. Our experiment detected Brd4 expressed in both normal synovium and periprosthetic osteolysis interface membrane, but the expression increased in the interface membrane as compared with that in normal synovium. Treatment with Ti particles significantly increased TNF-α, IL-6, and IL-1ß production in RAW264.7 cells, which was inhibited by JQ1 or Brd4-siRNA. Ti particles enhanced the expression of Brd4, which was abrogated by JQ1. Ti particles enhanced NF-κB p65 and IKK phosphorylation and attenuated IκBα protein expression, which were abrogated by JQ1. Co-immunoprecipitation analysis indicated that Ti particles promoted the binding of Brd4 to acetylated NF-κB p65 (lysine-310), which was also abrogated in JQ1-treated RAW264.7 cells. In conclusion, Brd4 expression increases in interface membrane and Brd4 participates in the production of pro-inflammatory cytokines induced by Ti particles via promoting the activation of NF-κB signaling and binding to acetylated NF-κB p65 (lysine-310) in mouse macrophages.


Assuntos
Citocinas/biossíntese , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Proteínas Nucleares/metabolismo , Titânio/farmacologia , Fatores de Transcrição/metabolismo , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/metabolismo , Macrófagos/citologia , Camundongos , NF-kappa B/metabolismo , Proteínas Nucleares/genética , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/metabolismo , Fatores de Transcrição/genética
17.
Biochem Biophys Res Commun ; 506(4): 805-811, 2018 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-30389139

RESUMO

Cardiac hypertrophy is a maladaptive response to pressure overload and it's an important risk factor for heart failure and other adverse cardiovascular events. Aromadendrin (ARO) has remarkable anti-lipid peroxidation efficacy and is a potential therapeutic medicine for the management of diabetes and cardiovascular diseases. In this study, we established the cardiac hypertrophy cell model in rat neonatal ventricular cardiomyocytes (RNVMs) with phenylephrine. The cell model was characterized by the increased protein synthesis and cardiomyocyte size, which can be normalized by ARO treatment in both concentration- and time-dependent manner. In transverse aortic constriction (TAC) induced cardiac hypertrophy model, ARO administration improved the impairment of cardiac function and alleviated the cardiac hypertrophy indicators, like ventricular mass/body weight, myocyte cross-sectional area, and the expression of ANP, BNP and Myh7. ARO treatment also suppressed the cardiac fibrosis and the correlated fibrogenic genes. Our further investigation revealed ARO could down-regulate pressure overload-induced Malondialdehyde (MDA) and 4-HNE expression, restore the decrease of GSH/GSSG ratio, meanwhile prevent nuclear translocation of NFAT and the activation of MAPKs pathways. Collectively, ARO has a protective effect against experimental cardiac hypertrophy in mice, suggesting its potential as a novel therapeutic drug for pathological cardiac hypertrophy.


Assuntos
Cardiomegalia/tratamento farmacológico , Regulação para Baixo , Flavonoides/uso terapêutico , Sistema de Sinalização das MAP Quinases , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Fibrose , Flavonoides/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Transcrição NFATC/metabolismo , Fenilefrina , Pressão , Biossíntese de Proteínas/efeitos dos fármacos
18.
Arterioscler Thromb Vasc Biol ; 37(3): 476-484, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28062495

RESUMO

OBJECTIVE: RNA polymerase I (Pol I)-dependent rRNA synthesis is a determinant factor in ribosome biogenesis and thus cell proliferation. The importance of dysregulated Pol I activity in cardiovascular disease, however, has not been recognized. Here, we tested the hypothesis that specific inhibition of Pol I might prevent arterial injury-induced neointimal hyperplasia. APPROACH AND RESULTS: CX-5461 is a novel selective Pol I inhibitor. Using this tool, we demonstrated that local inhibition of Pol I blocked balloon injury-induced neointima formation in rat carotid arteries in vivo. Neointimal development was associated with augmented rDNA transcriptional activity as evidenced by the increased phosphorylation of upstream binding factor-1. The beneficial effect of CX-5461 was mainly mediated by inducing G2/M cell cycle arrest of proliferating smooth muscle cells without obvious apoptosis. CX-5461 did not induce p53 stabilization but increased p53 phosphorylation and acetylation and activated the ataxia telangiectasia mutated/ataxia telangiectasia and Rad3-related (ATR) pathway. Inhibition of ATR, but not of ataxia telangiectasia mutated, abolished the cytostatic effect of CX-5461 and p53 phosphorylation. In addition, inhibition of p53 or knockdown of the p53 target GADD45 mimicked the effect of ATR inhibition. In vivo experiments showed that the levels of phospho-p53 and acetyl-p53, and activity of the ataxia telangiectasia mutated/ATR pathway were all augmented in CX-5461-treated vessels. CONCLUSIONS: Pol I can be therapeutically targeted to inhibit the growth of neointima, supporting that Pol I is a novel biological target for preventing arterial restenosis. Mechanistically, Pol I inhibition elicited G2/M cell cycle arrest in smooth muscle cells via activation of the ATR-p53 axis.


Assuntos
Benzotiazóis/farmacologia , Lesões das Artérias Carótidas/tratamento farmacológico , Músculo Liso Vascular/efeitos dos fármacos , Naftiridinas/farmacologia , Neointima , RNA Polimerase I/antagonistas & inibidores , Acetilação , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Lesões das Artérias Carótidas/enzimologia , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/patologia , Artéria Carótida Primitiva/efeitos dos fármacos , Artéria Carótida Primitiva/enzimologia , Artéria Carótida Primitiva/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Hiperplasia , Masculino , Camundongos , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Fosforilação , RNA Polimerase I/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
19.
Cell Biol Int ; 41(1): 71-78, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27592589

RESUMO

The canonical Wnt pathway is vital to bone physiology by increasing bone mass through elevated osteoblast survival. Although investigated extensively in stem cells, its role in osteoblastic MC3T3-E1 cells has not been completely determined. To explore how this pathway is regulated by different conditions, we assessed the anti-apoptotic effects of substance P on the canonical Wnt pathway in MC3T3-E1 cells by treating cells with serum deprivation or serum starving with "substance P," a neuropeptide demonstrated to promote bone growth and stimulate Wnt signaling. The results showed that serum deprivation both induced apoptosis and activated Wnt signal transduction while substance P further stimulated the Wnt pathway via the NK-1 receptor but protected the cells from apoptotic death. Fast-tracking of Wnt signaling by substance P was also noted. These results indicate that nutritional deprivation and substance P synergistically activated the canonical Wnt pathway, a finding that helps to reveal the role of Wnt signaling in bone physiology affected by nutritional deprivation and neuropeptide substance P.


Assuntos
Apoptose/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Substância P/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Meios de Cultura Livres de Soro , Camundongos , Receptores da Neurocinina-1/metabolismo , beta Catenina/metabolismo
20.
Clin Exp Pharmacol Physiol ; 44(3): 362-370, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27873355

RESUMO

Pulmonary vascular remodelling is a common feature among the heterogeneous disorders that cause pulmonary arterial hypertension (PAH), and pulmonary arterial smooth muscle cells (PASMCs) proliferation impact the long-term prognosis of the patient. Isoquercitrin (IQC) is a flavonoid with anti-oxidative, anti-inflammatory and anti-proliferative activations. This study aimed to investigate whether IQC could prevent PASMCs proliferation and vascular remodelling in monocrotaline (MCT) induced PAH. Male Wistar rats were administered with Vehicle or 0.1% IQC maintain feed after MCT (40 mg/kg) injection. Haemodynamic changes, right ventricular hypertrophy and lung morphological features were assessed 3 weeks later. MCT-induced PAH, pulmonary vascular remodelling and PASMCs proliferation in Vehicle-treated rats. IQC reduced the right ventricle systolic pressure (RVSP), the ratio of RV/LV+S and the RV hypertrophy. IQC significantly alleviated the expression of proliferating cell nuclear antigen (PCNA), smooth muscle α-actin (α-SMA), and the percentage of fully muscularized small arterioles. In vitro studies, PASMCs were pretreated with IQC and stimulated with platelet-derived growth factor (PDGF)-BB (20 ng/mL). IQC suppressed PDGF-BB-induced PASMCs proliferation and caused G0/G1 phase cell cycle arrest. IQC downregulated the expression of Cyclin D1 and CDK4 as well as inhibited p27Kip1 degradation. Meanwhile, IQC negatively modulated PDGF-BB-induced phosphorylation of PDGF-Rß, Akt/GSK3ß and ERK1/2. IQC ameliorated MCT-induced pulmonary vascular remodelling via suppressing PASMCs proliferation and blocking PDGF-Rß signalling pathway.


Assuntos
Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Hipertensão Pulmonar/prevenção & controle , Miócitos de Músculo Liso/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , Quercetina/análogos & derivados , Animais , Antioxidantes/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Masculino , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Quercetina/farmacologia , Quercetina/uso terapêutico , Ratos Wistar , Remodelação Vascular/efeitos dos fármacos
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