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1.
Neurochem Res ; 48(10): 3129-3145, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37338793

RESUMO

Previous studies have shown that AMPK plays an important role in cerebral ischemia-reperfusion injury by participating in apoptosis, but the exact mechanism and target of action remains unclear. This study aimed to investigate the protective mechanism of AMPK activation on brain injury secondary to cardiac arrest. HE, Nills and TUNEL assays were used to evaluate neuronal damage and apoptosis. The relationships between AMPK, HNF4α and apoptotic genes were verified by ChIP-seq, dual-luciferase and WB assays. The results showed that AMPK improved the 7-day memory function of rats, and reduced neuronal cell injury and apoptosis in the hippocampal CA1 region after ROSC, while the use of HNF4α inhibitor weakened the protective effect of AMPK. Further research found that AMPK positively regulated the expression of HNF4α, and AMPK could promote the expression of Bcl-2 and inhibit the expression of Bax and Cleaved-Caspase 3. In vitro experiments showed that AMPK ameliorated neuronal injury by inhibiting apoptosis through the activation of HNF4α. Combined with ChIP-seq, JASPAR analysis and Dual-luciferase assay, the binding site of HNF4α to the upstream promoter of Bcl-2 was found. Taken together, AMPK attenuates brain injury after CA by activating HNF4α to target Bcl-2 to inhibit apoptosis.


Assuntos
Lesões Encefálicas , Parada Cardíaca , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Parada Cardíaca/complicações , Parada Cardíaca/tratamento farmacológico
2.
ScientificWorldJournal ; 2014: 241085, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25045729

RESUMO

A fault-tolerant permanent-magnet vernier (FT-PMV) machine is designed for direct-drive applications, incorporating the merits of high torque density and high reliability. Based on the so-called magnetic gearing effect, PMV machines have the ability of high torque density by introducing the flux-modulation poles (FMPs). This paper investigates the fault-tolerant characteristic of PMV machines and provides a design method, which is able to not only meet the fault-tolerant requirements but also keep the ability of high torque density. The operation principle of the proposed machine has been analyzed. The design process and optimization are presented specifically, such as the combination of slots and poles, the winding distribution, and the dimensions of PMs and teeth. By using the time-stepping finite element method (TS-FEM), the machine performances are evaluated. Finally, the FT-PMV machine is manufactured, and the experimental results are presented to validate the theoretical analysis.

3.
Front Bioeng Biotechnol ; 11: 1297727, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38260743

RESUMO

The improvement of the steering performance of jet robots is challenging due to single inflexible jet aperture. Scallops provide a potential solution with hard shells and a double-hole jet propulsion, which are expected to achieve fast steering movement under water. Inspired by scallops, a bionic propulsion dynamic mesh is proposed in this article, and a three-dimensional computational model of scallops is established. We further calculated the scallop propulsion mechanism under the swing of shells with different shapes. The coupling of simultaneous swing of two shells and their coupling with velum are presented, revealing the unique movement mechanism of Bivalvia. Based on this, the advantages of the double-hole jet propulsion are applied to develop a scallop robot with excellent steering capabilities. Experiments are conducted to verify the steering performance of the scallop robot.

4.
Clin Cancer Res ; 28(24): 5297-5305, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-35653122

RESUMO

PURPOSE: Patients with recurrent or metastatic cervical cancer have limited treatment options after platinum-containing treatment. We initiated a phase I study to assess SHR-1701, a novel bifunctional fusion protein composed of a mAb against programmed death ligand 1 (PD-L1) fused with the extracellular domain of TGFß receptor II, in solid tumors (NCT03774979). Here, results from the cervical cancer cohort are presented. PATIENTS AND METHODS: Patients with recurrent or metastatic cervical cancer who progressed during or after platinum-based therapy were enrolled to receive SHR-1701 at 30 mg/kg every 3 weeks. Primary endpoint was objective response rate (ORR) per RECIST v1.1. RESULTS: In total, 32 patients were recruited. ORR was 15.6% [95% confidence interval (CI), 5.3-32.8], and disease control rate was 50.0% (95% CI, 31.9-68.1). Responses were still ongoing in 80.0% of the responders; 6-month duration of response rate was 80.0% (95% CI, 20.4-96.9). Median progression-free survival (PFS) was 2.7 months (95% CI, 1.4-4.1). Of note, as assessed by immune-modified RECIST, median PFS was 4.1 months (95% CI, 1.6-4.3). Overall survival rate at 12 months was 54.6% (95% CI, 31.8-72.7). Treatment-related adverse events of grade 3 or 4 were reported in 11 (34.4%) patients. No treatment-related deaths occurred. No difference in ORR was found between patients with PD-L1 combined positive score ≥1 or <1; patients with high phosphorylated SMAD2 level in immune cells or tumor cells had numerically higher ORR. CONCLUSIONS: SHR-1701 exhibits encouraging antitumor activity and controllable safety in patients with recurrent or metastatic cervical cancer after platinum-based regimens, and therefore might provide another treatment option for this population. See related commentary by Miller and Friedman, p. 5238.


Assuntos
Antineoplásicos Imunológicos , Neoplasias do Colo do Útero , Feminino , Humanos , Antígeno B7-H1 , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Anticorpos Monoclonais Humanizados , Fator de Crescimento Transformador beta/genética , Anticorpos Monoclonais
5.
Oncol Rep ; 35(5): 2691-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26986967

RESUMO

Oridonin (ORI), a diterpenoid purified from Rabdosia rubescens, has been reported as a promising chemotherapy drug for colon cancer treatment; yet, the precise mechanisms underlying this anticancer activity remain unclear. In the present study, we investigated the anticancer effect of ORI in HCT116 cells, and dissected the possible molecular mechanisms underlying this activity. With crystal violet staining, flow cytometry and western blot assay, we found that ORI effectively inhibited the proliferation and induced the apoptosis of HCT116 cells. Further analysis of the results indicated that BMP7 was greatly upregulated by ORI in the HCT116 cells, but its endogenous expression in FHC cells was apparently lower than that in the colon cancer cell lines. Exogenous expression of BMP7 inhibited the proliferation of the HCT116 cells, and substantially potentiated the anticancer effect of ORI. However, the specific antibody of BMP7 nearly abolished this anticancer activity of ORI in the HCT116 cells. Meanwhile, ORI exerted no significant effect on the level of phosphorylated Smad1/5/8 or total p38 MAPK, but greatly increased the level of phosphorylated p38 MAPK in the HCT116 cells. A p38 MAPK-specific inhibitor partly reversed the antiproliferative effect of BMP7 in the HCT116 cells, but prominently promoted the effect of the BMP7 antibody on proliferation. Exogenous expression of BMP7 increased the ORI-induced phosphorylation of p38 MAPK, while the BMP7 antibody almost abolished the ORI-elevated p38 MAPK phosphorylation. Our findings suggest that ORI may be an efficacious drug for colon cancer treatment. This anticancer activity of ORI may be mediated by upregulating BMP7 at least to increase the activation of p38 MAPK.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteína Morfogenética Óssea 7/metabolismo , Proliferação de Células/efeitos dos fármacos , Diterpenos do Tipo Caurano/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose/efeitos dos fármacos , Proteína Morfogenética Óssea 7/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Expressão Gênica , Células HCT116 , Humanos , Sistema de Sinalização das MAP Quinases , Regulação para Cima
6.
Oncol Rep ; 35(2): 939-47, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26555012

RESUMO

Colon cancer is one of the most common malignancies of the digestive system. Although more effective therapeutic strategies have been developed in the last decades, there is still a great clinical need to explore new treatment regimens for colon cancer due to the undesirable prognosis. In the present study, we investigated the anticancer activity of resveratrol (Res) in human colon cancer cells, and the possible mechanism underlying this effect. We employed crystal violet staining, flow cytometry and western blotting to test the antiproliferation- and apoptosis-inducing effects of Res in LoVo cells. A xenograft tumor model was also introduced to confirm the in vivo anticancer effect of Res. Using PCR, western blotting, a recombinant adenovirus and a specific inhibitor of p38 MAPK or bone morphogenetic protein receptor (BMPR) to explore the possible molecular mechanisms. We found that Res markedly inhibited the proliferation and promoted the apoptosis of LoVo cells, and suppressed the in vivo tumor growth of colon cancer. Res substantially upregulated the expression of bone morphogenetic protein 9 (BMP9). Exogenous expression of BMP9 enhanced the anticancer effect of Res in LoVo cells, while BMP9 knockdown partly reduced this activity. Res increased the activation of p38 MAPK, which was enhanced by the exogenous expression of BMP9. The anticancer activity of Res, or Res combined with BMP9, was reduced partly by the p38 MAPK inhibitor. The BMPR inhibitor almost abolished the Res-induced activation of p38 MAPK, and attenuated the antiproliferative effect of Res in the LoVo cells. Our findings strongly suggest that the anticancer effect of Res in human colon cancer cells may be partly mediated by upregulation of BMP9 to activate p38 MAPK in a BMPR-dependent manner.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/patologia , Fatores de Diferenciação de Crescimento/metabolismo , Estilbenos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Fator 2 de Diferenciação de Crescimento , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Resveratrol , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Drug Des Devel Ther ; 9: 2139-48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25931810

RESUMO

Recent studies have demonstrated that paclitaxel might inhibit renal fibrosis. However, the underlying molecular mechanism remains unclear. In this study, we hypothesized that low-dose paclitaxel may block the STAT3 (signal transducer and activator of transcription 3) signaling to attenuate fibrosis in a mouse model with unilateral ureteral obstruction. Both NRK-49F cells and mice with unilateral ureteral obstruction were treated with paclitaxel. The results showed that paclitaxel treatment resulted in a dose- and time-dependent decrease in tyrosine-phosphorylated STAT3, and inhibited the expression of fibronectin, alpha-smooth muscle actin (α-SMA), and collagen I in cultured NRK-49F cells. S3I-201, an STAT3 inhibitor, also suppressed the expression of fibronectin, α-SMA, and collagen I in cultured NRK-49F cells. Mechanistically, paclitaxel treatment blocked the STAT3 activity by disrupting the association of STAT3 with tubulin and inhibiting STAT3 nucleus translocation. Furthermore, paclitaxel also ameliorated renal fibrosis by down-regulating the expression of fibronectin, α-SMA, and collagen I, and suppressed the infiltration of macrophages and production of TNF-α, IL-1ß, TGF-ß, and ICAM-1 (intercellular adhesion molecule 1) by inhibition of STAT3 activity in obstructive nephropathy. These results suggest that paclitaxel may block the STAT3 activity by disrupting the association of STAT3 with tubulin and inhibiting STAT3 nucleus translocation, consequently leading to the suppression of renal interstitial fibroblast activation and the development of renal fibrosis, and inhibition of proinflammatory cytokine production.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Fibroblastos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Nefrite Intersticial/tratamento farmacológico , Nefrite Intersticial/patologia , Paclitaxel/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Fibrose/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
8.
Int J Oncol ; 46(3): 1205-13, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25524807

RESUMO

Colon cancer is one of the most common malignancies, causes considerable morbidity and mortality. The current treatment for colon cancer is more modest than had been hoped. There is an urgent clinical need to explore new agents or adjuvants for colon cancer treatment. Natural products and their derivates act as one of the major source for anticancer agent. In the present study, we investigated the anti-proliferation and chemoprevention effects of tetrandrine (Tet) on colon cancer cells to uncover the possible molecular basis of this effect. We found that Tet can inhibit proliferation and induce apoptosis in LoVo cells. With dimethylhydrazine (DMH) and dextran sodium sulfate (DSS) induced colon cancer model, we found that Tet can prevent or inhibit DMH plus DSS induced aberrant crypt foci (ACF) and colon cancer formation, as well as suppress tumor growth in the xenograft colon cancer model. Tet can downregulate the expression of IGFBP-5 in LoVo cells. Exogenous expression of IGFBP-5 can attenuate the anti-cancer activity of Tet, while IGFBP-5 knockdown potentiates this effect of Tet on LoVo cells. Tet can inhibit Wnt/ß-catenin signaling transduction, which can be partly reversed by exogenous expression of IGFBP-5, but is enhanced by IGFBP-5 knockdown. Our results demonstrated that the anticancer activity of Tet in colon cancer cells may be mediated partly by downregulating the expression of IGFBP-5, thus inactivating Wnt/ß-catenin signaling transduction.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzilisoquinolinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Animais , Proliferação de Células/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Feminino , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/antagonistas & inibidores , Masculino , Camundongos , Camundongos Nus , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Int J Oncol ; 45(1): 104-12, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24756222

RESUMO

Colon cancer is one of the most common malignancies and the treatments for colon cancer have been developed substantially in the last decades, but there is still a great clinical need to explore new treatment regimens due to the undesirable prognosis. In this investigation, we demonstrated the anti-proliferative and apoptosis-inducing activities of resveratrol (Res) in human colon cancer cells, and the possible mechanisms underlying these effects. We used crystal violet staining, flow cytometry and western blotting to validate the anti-proliferative and apoptosis-inducing effects of Res on HCT116 cells. A xenograft tumor model was used to confirm the anti-proliferative effects of Res. We employed polymerase chain reaction, western blotting, recombinant adenovirus and luciferase reporter assay to explore the possible mechanism(s) of action. We found that Res inhibits significantly the proliferation and promotes apoptosis in HCT116 cells, as well as inhibits the xenograft tumor growth of colon cancer. Res upregulates the expression of phosphatase and tensin homolog (PTEN) and decreases the phosphorylation of Akt1/2. The exogenous expression of PTEN inhibits the PI3K/Akt signal and promotes the anti-proliferative effects of Res in HCT116 cells, while knockdown of PTEN increases PI3K/Akt signal but reduces the anti-proliferative function of Res. The protein and mRNA expression of ß-catenin are all decreased by Res concentration-dependently. Thus, our findings strongly suggest that the anti-proliferative effects of Res in human colon cancer cells may be mediated by regulating separately the PTEN/PI3K/Akt and Wnt/ß-catenin signaling.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Estilbenos/administração & dosagem , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Neoplasias Experimentais , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
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