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1.
Vaccine ; 37(44): 6688-6695, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31537445

RESUMO

Porcine circovirus type 2 (PCV2) is one of the major swine pathogens causing high economic losses due to PCV2-associated disease (PCVAD). PCV2 infection is not only immunosuppressive by damaging lymphoid tissues but is also exacerbated by co-infections with other pathogens including Mycoplasma hyopneumoniae. While PCV2 can be divided into several genotypes, currently only PCV2a, PCV2b and PCV2d are globally prevalent and considered of major importance. Most commercial PCV2 vaccines are based on PCV2a isolates; however, the high prevalence of PCV2b and PCV2d in the global pig population is raising concerns among pig veterinarians. The objective of this study was to evaluate the efficacy of an experimental PCV2b-based subunit vaccine in a combined PCV2b and M. hyopneumoniae coinfection model. Briefly, a total of 49 PCV2- and M. hyopneumoniae-free 3-week-old pigs were randomly divided into four groups: A non-vaccinated, non-infected NEG-CONTROL group, a non-vaccinated, PCV2b-infected, POS-CONTROL group, and two vaccinated and PCV2b-infected groups (SINGLE-VAC, DUAL-VAC). SINGLE-VAC and DUAL-VAC pigs were vaccinated at 3 weeks of age and DUAL-VAC pigs received a booster dose at 5 weeks of age. All pigs, except NEG-CONTROLs, were experimentally infected with M. hyopneumoniae 28 days after initial vaccination and challenged with PCV2b one week later. The pigs were necropsied 21 days after PCV2b challenge. Prior to PCV2b challenge, both vaccinated groups had detectable humoral and cell-medicated immune responses to PCV2. Vaccination significantly reduced PCV2b viremia and also reduced or eliminated PCV2-associated lymphoid lesions compared to the POS-CONTROL pigs. Under the study conditions, an experimental PCV2b vaccine protected conventional growing pigs against PCV2b viremia and associated lesions in a coinfection model with some advantages of the two-dose regimen versus the one dose regimen. Both protocols induced neutralizing antibodies against PCV2a and PCV2d prior to challenge.

2.
Virology ; 538: 35-44, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31561059

RESUMO

Immuno-stimulatory class I-restricted cytotoxic T lymphocytes (CTL) epitopes of porcine reproductive and respiratory syndrome virus (PRRSV) are important for vaccine development. In this study we first determined the expression frequency of swine leukocyte antigen (SLA) class I alleles in commercial pigs in the United States. The SLA genotyping result allowed us to predict potential CTL epitopes from a contemporary strain of PRRSV (RFLP 1-7-4) by using bioinformatic tools. The predicted epitopes were then evaluated in an ex vivo stimulation assay with peripheral blood mononuclear cells isolated from pigs experimentally-infected with PRRSV. Using flow-cytometry analysis, we identified a number of immuno-stimulatory CTL epitopes, including two peptides from GP3 and two from Nsp9 that significantly improved both degranulation marker CD107a and IFN-γ production in cytotoxic CD4+CD8+ T cells, CD8+ T cells, and γδ T cells, and two peptides that inhibited IFN-γ production. These CTL epitopes will aid future vaccine development against PRRSV.

3.
Phys Chem Chem Phys ; 21(32): 17836-17845, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31378800

RESUMO

In organic-inorganic hybrid perovskite solar cells, though the current density-voltage (J-V) hysteresis phenomenon is accepted to be caused by ion migration coupled with charge carrier recombination, there are still rich hysteresis characteristics (various J-V hysteresis loops) remaining to be explained. Here, a systematic drift-diffusion simulation study is conducted to explore the effect of interfacial recombination lifetime (τinterface), bulk charge carrier lifetime (τbulk) and mobility (µ) on J-V hysteresis behaviors. The simulation results show that, for devices with only interfacial recombination, the decrease of τinterface will lead to J-V hysteresis loops with a large gap on the open circuit side. For devices with only bulk recombination, the drop of τbulk will lead to J-V hysteresis loops with a large gap on the short circuit side. Meanwhile, in both cases, the decrease of µ aggravates the effect of interfacial and bulk recombination, while it has no effect on VOC. Our simulations reveal the effect of decreased τinterface, τbulk and µ on the J-V characteristics and explain the hysteresis loops with specific shapes, which have been reported in the literature.

4.
Diabetes Metab Res Rev ; : e3212, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31411368

RESUMO

OBJECTIVE: Accumulating evidence suggests an association between beta-cell apoptosis and the ASK1/JNK/BAX pathway. The aim of this study was to investigate the effects of a combined therapy of liraglutide and human umbilical cord mesenchymal stem cells (hUC-MSCs) on the glucose metabolism and islet beta-cell apoptosis, and further explore its relationship to the ASK1/JNK/BAX pathway. METHOD: Type 2 diabetes mellitus (T2DM) rat model was induced by a high-sugar and high-fat diet and intraperitoneal injection of low-dose streptozotocin (STZ) (30 mg/kg). Three days after STZ injection, diabetic rats were randomly treated with subcutaneous injection of liraglutide (200 µg/kg/12 h) for 8 weeks and or hUC-MSCs (1 × 106 /rat) at the first and fifth weeks. Diabetes-related physical and biochemical parameters, pancreatic histopathological changes, immunohistochemical staining, quantitative real-time polymerase chain reaction, and western blot were used to measure the expression of apoptosis signal-regulating kinase 1 (ASK1), Jun N-terminal kinase (JNK), Bcl-2 associated X protein (BAX), and B-cell lymphoma-2 (Bcl-2). RESULTS: Eight weeks after liraglutide or human umbilical cord mesenchymal stem cell administration, FPG, HbA1c , glucagon, body weight, and pancreatic ASK1, JNK, and BAX mRNA and proteins were significantly decreased, and the levels of serum C-p, INS and GLP-1, ratio of insulin positive area, and Bcl-2 expression were significantly increased in three treatment groups compared with T2DM group (P<.05). CONCLUSION: Liraglutide combined with hUC-MSCs improve glucose metabolism and inhibit islet beta-cell apoptosis in a ASK1/JNK/BAX pathway-dependent manner.

5.
EMBO J ; 38(15): e101964, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31267557

RESUMO

The IGF1R signaling is important in the malignant progression of cancer. However, overexpression of IGF1R has not been properly assessed in HCC. Here, we revealed that GSTZ1-1, the enzyme in phenylalanine/tyrosine catabolism, is downregulated in HCC, and its expression was negatively correlated with IGF1R. Mechanistically, GSTZ1-1 deficiency led to succinylacetone accumulation, alkylation modification of KEAP1, and NRF2 activation, thus promoting IGF1R transcription by recruiting SP1 to its promoter. Moreover, inhibition of IGF1R or NRF2 significantly inhibited tumor-promoting effects of GSTZ1 knockout in vivo. These findings establish succinylacetone as an oncometabolite, and GSTZ1-1 as an important tumor suppressor by inhibiting NRF2/IGF1R axis in HCC. Targeting NRF2 or IGF1R may be a promising treatment approach for this subset HCC.

6.
J Med Virol ; 91(11): 1960-1969, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31317546

RESUMO

Hepatitis E is an important global disease, causing outbreaks of acute hepatitis in many developing countries and sporadic cases in industrialized countries. Hepatitis E virus (HEV) infection typically causes self-limiting acute hepatitis but can also progress to chronic disease in immunocompromised individuals. The immune response necessary for the prevention of chronic infection is T cell-dependent; however, the arm of cellular immunity responsible for this protection is not currently known. To investigate the contribution of humoral immunity in control of HEV infection and prevention of chronicity, we experimentally infected 20 wild-type (WT) and 18 immunoglobulin knockout (JH-KO) chickens with a chicken strain of HEV (avian HEV). Four weeks postinfection (wpi) with avian HEV, JH-KO chickens were unable to elicit anti-HEV antibody but had statistically significantly lower liver lesion scores than the WT chickens. At 16 wpi, viral RNA in fecal material and liver, and severe liver lesions were undetectable in both groups. To determine the role of cytotoxic lymphocytes in the prevention of chronicity, we infected 20 WT and 20 cyclosporine and CD8+ antibody-treated chickens with the same strain of avian HEV. The CD8 + lymphocyte-depleted, HEV-infected chickens had higher incidences of prolonged fecal viral shedding and statistically significantly higher liver lesion scores than the untreated, HEV-infected birds at 16 wpi. The results indicate that CD8 + lymphocytes are required for viral clearance and reduction of liver lesions in HEV infection while antibodies are not necessary for viral clearance but may contribute to the development of liver lesions in acute HEV infection.

7.
Medicine (Baltimore) ; 98(24): e16019, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31192950

RESUMO

BACKGROUND: Sepsis is a complex and life-threatening systemic disease. A positive blood culture is the criterion standard of diagnosis for sepsis; however, it does not produce results for 24 to 72 hours. Besides, the clinical manifestations of sepsis are variable and nonspecific. Therefore, a new diagnostic biomarker for diagnosis of sepsis should be developed. The present study aims to assess the diagnostic value of intercellular adhesion molecule-1 (ICAM-1) in individuals with sepsis. METHODS: The literature will be searched in PubMed, EMBASE, the Cochrane Library, and Web of Science databases from the inception of each database up to June 2019. The methodological quality of eligible study will be assessed by Quality Assessment of Diagnostic Accuracy Studies tool-2 (QUADAS-2). Stata 15.1 software (version 15.1, Stata Corporation) will be used to calculate the pooled sensitivity, pooled specificity, pooled positive likelihood ratio, pooled negative likelihood ratio, pooled diagnostic odds ratio, pre-test probability, post-test probability, and summary receiver-operating characteristic curve for diagnostic value of ICAM-1. The I statistic will be used to test heterogeneity. Subgroup analysis will be used to explore the source of inconsistency. GRADE (Grading of Recommendations Assessment, Development, and Evaluation) system will be used to assess the certainty of evidence. This study will be conducted fully following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses of diagnostic test accuracy. RESULTS AND CONCLUSIONS: Our study will detect the potential of ICAM-1 for diagnosing the patients with sepsis and the results will be submitted to a peer-reviewed journal. DISCUSSION: The evidence will indicate that ICAM-1 is a valuable biomarker for detecting sepsis. This is a protocol of systematic review and meta-analysis, so the ethical approval and patient consent are not required.


Assuntos
Molécula 1 de Adesão Intercelular/metabolismo , Metanálise como Assunto , Sepse/metabolismo , Revisão Sistemática como Assunto , Biomarcadores/metabolismo , Humanos
8.
Pharmacol Res ; 146: 104294, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31175940

RESUMO

Breast cancer, the most prevalent cancer in women, remains the second in the list of cancer mortality, the majority of these fatalities resulted from estrogen receptor alpha (ERα) positive disease. ERα is well known for its function on breast cancer initiation and development and has become the most successful biomarker in breast cancers. Ophiobolins are sesterterpene compounds with a distinct tricyclic 5-8-5 ring and have presented anti-cancer activities. MHO7(6-epi-ophiobolin G)was isolated from products of a mangrove fungus in our previous research and demonstrated robust activity against breast cancer cells (BCCs). The investigation on the precise mechanism of MHO7 shows that MHO7 acts as a novel ERα down regulator different from the known molecules in ER + breast cancer cells. A whole-genome transcriptomic analysis on MCF-7 cells treated with MHO7 revealed the estrogen signaling pathway was the most affected pathway, and further evidence showed the de novo synthesis of ESR1 mRNA was inhibited. In addition, MHO7 down-regulated ERα at the protein level through multiple approaches. It not only bound to ERα, pushing helix 11 away in the agonist conformation but also increased the ERα degradation through the ubiquitin-proteasome system. These effects consequently caused decreasing of the transcriptional activity of ER modulation which was confirmed by the decreasing of estrogen receptor element (ERE) activity as well as downstream genes expressions like GREB1, BRCA1, MUC1 and CCND1. Combination of tamoxifen and MHO7 yield a synergistic effect on the inhibition of MCF-7 cells when treated around the IC50 values. Our results suggest that MHO7 is a very promising drug candidate and provides a novel drug version on ERα down-regulation to fighting with breast cancer.

9.
FEBS Open Bio ; 9(8): 1469-1476, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31250981

RESUMO

Wogonoside (Wg), a natural flavonoid, has anticancer effects against several human cancers. The purpose of the present study was to investigate the antitumor effects and underlying mechanisms of Wg on gastric cancer (GC) cell lines. We report that Wg treatment inhibited cell viability and induced apoptosis in human GC cell lines AGS and SGC-7901, and also retarded GC tumor growth in xenograft mice in vivo. We also found that the Wg exerted its antitumor effects against GC cells via induction of reaction oxygen species accumulation, mitochondrial dysfunction, and endoplasmic reticulum stress. Furthermore, C/EBP homologous protein knockdown inhibited apoptosis and increased the viability of Wg-treated GC cells. Our findings may facilitate the development of novel therapeutic agents for the treatment of GC.

10.
Adv Mater ; 31(30): e1901371, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31172590

RESUMO

Rapid and controllable formation of fluorescent carbon quantum dots (CQDs) is highly desirable in the fields of nanophotonics and biophotonics. Here, a novel strategy for creating CQDs, which emit white light efficiently under the excitation of either laser light or a mercury lamp, is proposed and demonstrated. The luminescent CQDs are generated by irradiating a poly(vinyl alcohol) (PVA) film doped with dense gold nanoparticles (AuNPs) with femtosecond laser pulses. The creation of CQDs from PVA is a two-step dehydration process mediated by AuNPs which act not only as heat sources but also as catalytic agents. The formation of CC, CC, and CO bonds is confirmed by infrared Fourier transformation spectroscopy and X-ray photoelectron spectroscopy. It is revealed both numerically and experimentally that a spatially localized temperature distribution at the deep subwavelength scale can be achieved in oligomers of AuNPs by resonantly exciting the Fano resonances formed in the oligomers of AuNPs, enabling the generation of CQDs with small diameters. As one of the potential applications, it is demonstrated that optical display and optical data storage with ultralow energy can be realized by selectively introducing luminescent CQDs in the AuNP/PVA film.

11.
Adv Ther ; 36(6): 1485-1496, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31004325

RESUMO

INTRODUCTION: China has the largest number of diabetic patients in the world. In the past 2 decades, the prevalence of diabetes in China has increased dramatically, and the current status of diabetes control in the diabetic population is not satisfactory. Although insulin is currently recognized in diabetes treatment guidelines as the therapeutic option for patients not adequately controlled by diet/exercise and oral agents, the proportion of patients with type 2 diabetes using insulin is still very low, and the time when insulin therapy is initiated is relatively late. In using insulin injections, concerns about the complexity of the treatment regimen, a fear of needles, and other psychological barriers can affect insulin treatment, impacting on patient compliance and potentially resulting in a poor treatment response. Another type of insulin injection device that has become available recently, the needle-free injector, is now being used in clinical practice because of its unique features and patients' injection experiences. The aims of this study are to investigate the efficacy and safety of the needle-free injector-based insulin treatment in blood glucose control in patients with type 2 diabetes, as compared with a conventional needle-based insulin treatment, and to evaluate patient satisfaction with the different insulin delivery methods. METHODS AND PLANNED OUTCOMES: A prospective, multicenter, randomized, open-label, parallel-group clinical trial was designed and implemented in China. A total of 420 patients with type 2 diabetes from ten research centers will be enrolled in the study. The primary efficacy endpoint is the change in the glycosylated hemoglobin (HbA1c) level from baseline to after 16 weeks of treatment after randomization. Secondary efficacy endpoints include measurements of blood glucose concentrations, the rate of achieving the target HbA1c level of less than 7%, patients' quality-of-life (as determined by the SF-36 questionnaire), the insulin dose administered, compliance with insulin therapy, and patients' satisfaction with their injection device. ETHICS AND DISSEMINATION: The study was approved by the Independent Ethics Committee (IEC) of Peking University Peoples Hospital and was conducted in accordance with the moral, ethical, and scientific principles of the declaration of Helsinki and the provisions of good clinical practice (GCP) in China. Written informed consent will be obtained from all participants before any study-related procedures are implemented. It is hoped that the study will provide evidence for the clinical application of the needle-free injector by providing data on its efficacy and safety, as compared with a conventional insulin pen, in the Chinese type 2 diabetes population. When available, the results will be published in an international peer-reviewed journal. TRIAL REGISTRATION: ClinicalTrials.gov Identifier, NCT03243903. Registration date, August 9, 2017. FUNDING: Beijing QS Medical Technology Co., Ltd.

12.
J Cell Biochem ; 120(9): 14860-14866, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31033015

RESUMO

Long-non-coding RNAs (lncRNA) AWPPH promotes the progression of liver and bladder cancer, indicating its oncogenic role. The current study aimed to explore the involvement of AWPPH in triple-negative breast cancer (TNBC). In the current study, we found that plasma levels of lncRNA AWPPH and microRNA-21 (miRNA-21) were upregulated in patients with TNBC than in healthy controls, and the upregulation of plasma lncRNA AWPPH and miRNA-21 distinguished early-stage patients with TNBC from healthy controls. Plasma levels of lncRNA AWPPH and miRNA-21 were significantly and positively correlated in both patients with TNBC and healthy controls. LncRNA AWPPH and miRNA-21 overexpression led to promoted cancer cells proliferation and improved cancer cell viability under carboplatin treatment, while lncRNA AWPPH small interfering RNA (siRNA) silencing played an opposite role. In addition, miRNA-21 overexpression attenuated the effects of lncRNA AWPPH siRNA silencing on of cancer cell behaviors. LncRNA AWPPH overexpression led to upregulated miRNA-21 in TNBC cells, while miRNA-21 overexpression also led to significantly upregulated lncRNA AWPPH expression. Therefore, lncRNA AWPPH and miRNA-21 may regulate cancer cell proliferation and chemosensitivity in TNBC by interacting with each other.

13.
Phytomedicine ; 59: 152803, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005811

RESUMO

BACKGROUND: Chrysanthemi Flos (CF), as a popular traditional Chinese medicine (TCM), has five main cultivars in China, namely "Chuju", "Boju", "Gongju", "Huaiju" and "Hangju". Due to their habitats and processing methods, great quality variations occur yet no systematical study has ever been carried out to evaluate such variations. PURPOSE: In this study, we aim to establish a new approach that can serve both as a quality control method and as an identification method for cultivars of CF. METHOD: The components in CF samples were identified by a combination of UPLC-ESI-Q-TOF/MS and GC/MS. Furthermore, a multimodal quantitative method was established by UPLC-UV coupled with principal component analysis (PCA) and the similarity evaluation system (SES), which was used to control and identify four cultivars of CF. RESULTS: 18 compounds of flavonoids and caffeoylquinic acids were identified and ten of them were quantified using UPLC-ESI-Q-TOF/MS. Different cultivars of CF could be clearly distinguished with the fingerprints evaluation and principal component analysis (PCA). A total of 74 volatile compounds were detected by GC/MS. The distinctness of volatile components was observed. By the combination of UPLC-ESI-Q-TOF/MS and GC/MS, an identification and quality control method for CF was successfully established. CONCLUSION: The combination of UPLC-ESI-Q-TOF/MS and GC/MS could act as a comprehensive multimodal method for both identification and quality control of herbal medicines. This study provided new insights into the overall evaluation method for herbal medicines possessing different cultivars.


Assuntos
Chrysanthemum/química , Medicamentos de Ervas Chinesas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , China , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Flores/química , Cromatografia Gasosa-Espectrometria de Massas/estatística & dados numéricos , Análise de Componente Principal , Controle de Qualidade , Ácido Quínico/análogos & derivados , Ácido Quínico/análise , Espectrometria de Massas por Ionização por Electrospray/estatística & dados numéricos , Compostos Orgânicos Voláteis/análise
14.
Exp Cell Res ; 378(2): 198-205, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30880031

RESUMO

Recent studies have shown that autophagy exhibits a protective role in acute kidney injury (AKI), and the accumulation of advanced oxidation protein products (AOPP) participates in the progression of kidney diseases. Our previous study indicated that AOPP induced injury in renal tubular epithelial cells (RTECs) through autophagy inhibition. Besides, we found that human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) enhanced autophagy in AOPP-treated RTECs, but the underlying mechanism remains unclear. We regulated microRNA-145 (miR-145) expression in HK-2 cells (a cell line of RTECs), or co-cultured hUC-MSCs with HK-2 cells and studied the autophagic activity in HK-2 cells to explore the underlying mechanism. Our data demonstrated that upregulated miR-145 increased LC3 II and Beclin 1 levels, decreased p62 level, three autophagy related proteins, inhibited the phosphorylation of PI3K/AKT/mTOR, and increased LC3B-positive staining and the autophagosome number. Furthermore, hUC-MSCs enhanced autophagy and inhibited phosphorylation of PI3K/AKT/mTOR in AOPP-treated HK-2 cells, which was then partially rescued using miR-145 knockdown in the hUC-MSCs co-culture system. In conclusion, our study showed that hUC-MSCs enhanced autophagy in AOPP-treated HK-2 cells mediated by miR-145 via inhibition of the PI3K/AKT/mTOR pathway, which indicated that hUC-MSCs might serve as a prospective therapy for AKI.

15.
Virus Res ; 265: 47-56, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30826338

RESUMO

Stress granules (SGs) are dynamic sites of cytosolic mRNA storage that are formed in response to stress conditions, including viral infection. SGs have been implicated in regulating several aspects of the host immune response to various pathogens. Porcine reproductive and respiratory syndrome virus (PRRSV), an economically-important global swine pathogen, reportedly induced SGs during replication, although the underlying mechanisms are poorly defined. In this study, we delineated the molecular mechanisms regulating the SG response to PRRSV infection. Using confocal microscopy, we first demonstrated that infection with PRRSV strain VR2385 induces an accumulation of the SG markers G3BP1, G3BP2, TIAR, eIF3b, and USP10 as well as mRNAs into punctate structures in the cytoplasm of infected host cells. Subsequently, we demonstrated that the PRRSV-induced SGs were in close proximity to viral replication complexes (VRCs) and processing bodies (P-bodies), and that SG formation was coordinated with inhibition of host cellular translation. Treatment of infected cells with cycloheximide disrupted the PRRSV-induced SGs. Furthermore, impairment of SG assembly by the shRNA-mediated knockdown of G3BP1, G3BP2 and USP10 did not affect viral replication. Collectively, these results demonstrate that PRRSV infection induces formation of SGs associated with VRCs, which is coordinated with the suppression of host cell protein synthesis. This is the first study to extensively characterize the formation and underlying mechanism of bona fide SGs during PRRSV infection. Our findings have important implications in understanding the mechanism of PRRSV-host interactions.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Interações Hospedeiro-Patógeno , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Replicação Viral , Animais , Proteínas de Transporte/genética , Humanos , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Estresse Fisiológico , Suínos
16.
J Exp Clin Cancer Res ; 38(1): 50, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717766

RESUMO

BACKGROUND: Altered glucose metabolism endows tumor cells with metabolic flexibility for biosynthesis requirements. Phosphoenolpyruvate carboxykinase 1 (PCK1), a key enzyme in the gluconeogenesis pathway, is downregulated in hepatocellular carcinoma (HCC) and predicts poor prognosis. Overexpression of PCK1 has been shown to suppress liver tumor growth, but the underlying mechanism remains unclear. METHODS: mRNA and protein expression patterns of PCK1, AMPK, pAMPK, and the CDK/Rb/E2F pathway were determined using qRT-PCR and western blotting. Cell proliferation ability and cell cycle were assessed by MTS assay and flow cytometric analysis. The effect of PCK1 on tumor growth was examined in xenograft implantation models. RESULTS: Both gain and loss-of-function experiments demonstrated that PCK1 deficiency promotes hepatoma cell proliferation through inactivation of AMPK, suppression of p27Kip1 expression, and stimulation of the CDK/Rb/E2F pathway, thereby accelerating cell cycle transition from the G1 to S phase under glucose-starved conditions. Overexpression of PCK1 reduced cellular ATP levels and enhanced AMPK phosphorylation and p27Kip1 expression but decreased Rb phosphorylation, leading to cell cycle arrest at G1. AMPK knockdown significantly reversed G1-phase arrest and growth inhibition of PCK1-expressing SK-Hep1 cells. In addition, the AMPK activator metformin remarkably suppressed the growth of PCK1-knockout PLC/PRF/5 cells and inhibited tumor growth in an orthotropic HCC mouse model. CONCLUSION: This study revealed that PCK1 negatively regulates cell cycle progression and hepatoma cell proliferation via the AMPK/p27Kip1 axis and supports a potential therapeutic and protective effect of metformin on HCC.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/patologia , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Quinases Ciclina-Dependentes/metabolismo , Regulação para Baixo , Fatores de Transcrição E2F/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Eur J Pharm Sci ; 130: 166-172, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30703444

RESUMO

BACKGROUND: Moguisteine is a non-narcotic peripheral antitussive drug that has been effective and well-tolerated in clinical studies. The aim of the present work was to investigate the pharmacokinetics of moguisteine given as single or multiple doses to healthy Chinese subjects. METHODS: In Stages 1-3 of this study, 12 healthy Chinese subjects (6 males and 6 females) participated in a randomized, open-label, single-dose, 3-period, 3-way crossover study, with a 24-h washout period between each treatment. Eligible subjects were randomized to receive a single dose of 100, 200 or 400 mg moguisteine. Blood was sampled before and up to 10 h after administration. In those receiving 200 mg moguisteine, urine was sampled at intervals of 0-2, 2-4, 4-6, 6-10, and 10-24 h. In Stage 4, subjects received a moguisteine tablet containing 200 mg three times daily for five consecutive days. Blood was sampled for up to 10 h after the last dose. HPLC-tandem mass spectrometry was used to determine concentrations of the moguisteine metabolite M1 in serum, while HPLC-UV was used to determine concentrations of M1 in urine. Safety of the dosing schedules was assessed based on physical examination, recording of adverse events, 12-lead electrocardiography, and laboratory tests. RESULTS: All subjects completed all four stages of the study. M1 was detectable at the shortest time points after moguisteine administration; the time to achieve peak concentration was 0.5-1.0 h in single dosing and 1.5 h in multiple dosing. Elimination half-life (t1/2) was 0.91-1.54 h in single dosing and 1.57 h in multiple dosing. AUC increased roughly proportionally with dose, while Cmax increased much more gradually with dose. During 5-day dosing of three tablets per day, a steady state concentration was reached on day 3, and the mean accumulation ratio was 0.87. At 24 h after a single dose of 200 mg moguisteine, approximately 34.0% of the resulting M1 was recovered in urine. Pharmacokinetics of moguisteine did not differ significantly between men and women, except among those receiving a single dose of 100 mg (P < 0.05). Mild adverse events (nausea, loose stool, abdominal distention, or dizziness) occurred in six subjects and resolved without treatment, while no serious adverse events were observed. CONCLUSION: Moguisteine was safe and well-tolerated by our healthy subjects, and it exhibited dose linearity but not proportionality when a single dose of 100-400 mg was given. M1 did not accumulate in subjects after multiple doses of moguisteine.


Assuntos
Antitussígenos/administração & dosagem , Antitussígenos/farmacocinética , Grupo com Ancestrais do Continente Asiático , Tiazolidinas/administração & dosagem , Tiazolidinas/farmacocinética , Adolescente , Adulto , Grupo com Ancestrais do Continente Asiático/genética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
J Cell Biochem ; 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30387173

RESUMO

Osteosarcoma (OS) is a primary malignant bone tumor with high morbidity. Developing new therapeutic approaches with neoadjuvant is of great interest in OS treatment. Reportedly, ataxia telangiectasia mutated (ATM)/ataxia telangiectasia and radiation resistance gene 3 related (ATR)-p53 signaling is considered as a critical DNA damage signaling pathway sensitizing cancer cells to chemotherapies; while wild-type p53-induced phosphatase 1 (WIP1), an oncogene overexpressed in diverse cancers, has been regarded as a critical inhibitor in the ATM/ATR-p53 DNA damage signaling pathway. Herein, the expression of WIP1 in OS tissues and cell lines was examined; to investigate the mechanism of WIP1 abnormal upregulation, online tools were used to predict the upstream regulatory microRNAs (miRNAs) targeting WIP1. Among the candidate miRNAs, the expression and detailed function of miR-590 were validated. Through binding to the 3'-untranslated region of WIP1, miR-590 inhibited WIP1 expression and, therefore, enhanced the effect of Dox on OS cell proliferation and apoptosis through downstream ATM-p53 signaling. Moreover, RELA could bind to the promoter region of miR-590 to inhibit its expression, thereby affecting downstream WIP1 and ATM-p53 signaling. The expression of p65 was upregulated in OS tissues, indicating that the effect of p65 inhibition on cell viability, apoptosis, and related mechanisms could be partially restored by miR-590 inhibition. Taken together, these results showed that p65-mediated miR-590/WIP1/ATM-p53 modulation might be a novel target to enhance the cellular effect of Dox on OS cell lines.

20.
Arthroscopy ; 34(12): 3258-3265, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30396800

RESUMO

PURPOSE: To compare the clinical outcomes and adverse events associated with irradiated and nonirradiated allografts in anterior cruciate ligament (ACL) reconstruction. METHODS: PubMed, Web of Science, and EMBASE were searched for randomized controlled trials from January 1990 to March 2018 to compare autograft with allograft in ACL reconstruction. Both objective and subjective outcomes of the function and adverse events were meta-analyzed. Two comparisons were summarized: (1) autograft and nonirradiated allograft and (2) autograft and irradiated allograft. The bias risk was based on the Cochrane Handbook for Systematic Reviews of Interventions. The overall risk ratio or weighted mean difference was calculated using a fixed- or random-effects model. Heterogeneity between studies was evaluated by the Q and the I2 statistics. RESULTS: Eleven trials were included in this review for meta-analysis. A total of 1,172 patients were involved (465 autograft and 461 nonirradiated allograft; 141 autograft and 138 irradiated allograft patients). The average follow-up varied from 2 to >10 years. The mean patient age varied from 22 to 32.8 years. The total failure rate was 2.5%. Our analyses demonstrated better clinical outcomes in autograft than irradiated allograft, which could be observed clearly through the International Knee Documentation Committee score (3.84; 95% confidence interval [CI], 1.93-5.76; P < .0001; I2 = 0%), Lysholm score (2.94; 95% CI, 0.66-5.22; P = .01; I2 = 0%), and Tegner score (0.14; 95% CI, -0.08 to 0.36; P = .22; I2 = 0%) with fewer adverse events 0.20 (95% CI, 0.11-0.39; P < .00001; I2 = 0%). There were no significant differences in autograft and nonirradiated allograft groups (P = .47, P = .27, P = .24, and P = .24, respectively). CONCLUSIONS: Autograft offered greater advantages in functional outcomes and adverse events than irradiated allograft in ACL reconstruction; however, there were no significant differences between autograft and nonirradiated allograft in ACL reconstruction. LEVEL OF EVIDENCE: Level II, meta-analysis of Level I and Level II studies.

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