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1.
Curr Drug Deliv ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38204256

RESUMO

BACKGROUND: Gefitinib (GFN) is an Epithelial Growth Factor Receptor (EGFR) inhibitor, and Food and Drug Administration (FDA) has approved medication to treat lung cancer. However, this investigation aimed to produce and characterize Gefitinib (GFN)-loaded chitosan and soy lecithin nanoparticles (NPs) modified with D-α-tocopheryl polyethylene glycol 1000 succinate mono ester (TPGS) and assess their therapeutic potential against HepG2 liver cell lines. METHODS: Chitosan, a cationic polymer with biocompatible and biodegradable properties, was combined with soy lecithin to develop the NPs loaded with GFN using a self-organizing ionic interaction methodology. RESULTS: The entrapment efficiency and drug loading were found to be 59.04±4.63 to 87.37±3.82% and 33.46±3.76 to 49.50±4.35%, respectively, and results indicated the encapsulation of GEN in NPs. The pH of the formulations was observed between 4.48-4.62. Additionally, all the prepared NPs showed the size and PDI range of 89.2±15.9 nm to 799.2±35.8 nm and 0.179±0.065 to 0.455±0.097, respectively. The FTIR bands in optimized formulation (GFN-NP1) indicated that the drug might be contained within the NP's core. The SEM photograph revealed the spherical shape of NPs. The kinetic release model demonstrated the combination of diffusion and erosion mechanisms. The IC50 value of GFN and GFN-NP1 formulation against the HepG2 cell lines were determined and found to be 63.22±3.36 µg/ml and 45.80±2.53 µg/ml, respectively. DAPI and PI staining agents were used to detect nuclear morphology. CONCLUSION: It was observed that the optimized GFN-NP1 formulation successfully internalized and inhibited the growth of HepG2 cells. Hence, it can be concluded that the prepared NPs can be a new therapeutic option for treating liver cancer.

2.
J Biol Chem ; 299(11): 105335, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37827291

RESUMO

Hepatoma-derived growth factor (HDGF) overexpression and uncontrolled reactive oxygen species (ROS) accumulation are involved in malignant transformation and poor prognosis in various types of cancer. However, the interplay between HDGF and ROS generation has not been elucidated in hepatocellular carcinoma. Here, we first analyzed the profile of HDGF expression and ROS production in newly generated orthotopic hepatomas by ultrasound-guided implantation. In situ superoxide detection showed that HDGF-overexpressing hepatomas had significantly elevated ROS levels compared with adjacent nontumor tissues. Consistently, liver tissues from HDGF-deficient mice exhibited lower ROS fluorescence than those from age- and sex-matched WT mice. ROS-detecting fluorescent dyes and flow cytometry revealed that recombinant HDGF (rHDGF) stimulated the production of superoxide anion, hydrogen peroxide, and mitochondrial ROS generation in cultured hepatoma cells in a dose-dependent manner. In contrast, the inactive Ser103Ala rHDGF mutant failed to promote ROS generation or oncogenic behaviors. Seahorse metabolic flux assays revealed that rHDGF dose dependently upregulated bioenergetics through enhanced basal and total oxygen consumption rate, extracellular acidification rate, and oxidative phosphorylation in hepatoma cells. Moreover, antioxidants of N-acetyl cysteine and MitoQ treatment significantly inhibited HDGF-mediated cell proliferation and invasive capacity. Genetic silencing of superoxide dismutase 2 augmented the HDGF-induced ROS generation and oncogenic behaviors of hepatoma cells. Finally, genetic knockdown nucleolin (NCL) and antibody neutralization of surface NCL, the HDGF receptor, abolished the HDGF-induced increase in ROS and mitochondrial energetics. In conclusion, this study has demonstrated for the first time that the HDGF/NCL signaling axis induces ROS generation by elevating ROS generation in mitochondria, thereby stimulating liver carcinogenesis.


Assuntos
Carcinoma Hepatocelular , Animais , Camundongos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Espécies Reativas de Oxigênio , Carcinogênese/genética
3.
BMJ Open ; 13(6): e070490, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286314

RESUMO

OBJECTIVE: Hepatitis C is an important risk factor for cirrhosis and liver cancer in the Taiwanese population. Domestic prisons reported a higher rate of hepatitis C infection than the national average. Efficient and effective treatment of patients with hepatitis C in prisons is required to decrease the number of infections. This study analysed the effectiveness of hepatitis C treatment and its side effects in prison patients. DESIGN: This retrospective analysis included adult patients with hepatitis C who received direct-acting antiviral agents between 2018 and 2021. SETTING: The special hepatitis C clinics in the two prisons were run by a medium-sized hepatitis C treatment hospital in Southern Taiwan. Three direct-acting antiviral agents, sofosbuvir/ledipasvir for 12 weeks, glecaprevir/pibrentasvir for 8 or 12 weeks and sofosbuvir/velpatasvir for 12 weeks, were adopted based on patient characteristics. PARTICIPANTS: 470 patients were included. OUTCOME MEASURE: The sustained virological response at 12 weeks after the end of treatment was compared between the different groups. RESULTS: Most of the patients were men (70.0%) with a median age of 44 years. The most prevalent hepatitis C virus genotype was genotype 1 (44.26%). A total of 240 patients (51.06%) had a history of injectable drug use; 44 (9.36%) and 71 (15.11%) patients were coinfected with hepatitis B virus and HIV, respectively. Only 51 patients (10.85%) had liver cirrhosis. Most patients (98.30%) had normal renal function or no history of kidney disease. The patients had a sustained virological response achievement rate of 99.2%. The average incidence of adverse reactions during treatment was approximately 10%. Many of the adverse reactions were mild and resolved spontaneously. CONCLUSION: Direct-acting antiviral agents are effective for treating hepatitis C in Taiwanese prisoners. These therapeutics were well-tolerated by the patient population.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Hepatite C Crônica , Hepatite C , Adulto , Masculino , Humanos , Feminino , Sofosbuvir/efeitos adversos , Antivirais/efeitos adversos , Prisões , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Estudos Retrospectivos , Taiwan/epidemiologia , Quimioterapia Combinada , Hepatite C/tratamento farmacológico , Resultado do Tratamento , Cirrose Hepática/tratamento farmacológico , Genótipo
4.
Med Sci Monit ; 29: e939949, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183387

RESUMO

BACKGROUND Self-injection locking (SIL) radar uses continuous-wave radar and an injection-locked oscillator-based frequency discriminator that receives and demodulates radar signals remotely to monitor vital signs. This study aimed to compare SIL radar with traditional electrocardiogram (ECG) measurements to monitor respiratory rate (RR) and heartbeat rate (HR) during the COVID-19 pandemic at a single hospital in Taiwan. MATERIAL AND METHODS We recruited 31 hospital staff members (16 males and 15 females) for respiratory rates (RR) and heartbeat rates (HR) detection. Data acquisition with the SIL radar and traditional ECG was performed simultaneously, and the accuracy of the measurements was evaluated using Bland-Altman analysis. RESULTS To analyze the results, participates were divided into 2 groups (individual subject and multiple subjects) by gender (male and female), or 4 groups (underweight, normal weight, overweight, and obesity) by body mass index (BMI). The results were analyzed using mean bias errors (MBE) and limits of agreement (LOA) with a 95% confidence interval. Bland-Altman plots were utilized to illustrate the difference between the SIL radar and ECG monitor. In all BMI groups, results of RR were more accurate than HR, with a smaller MBE. Furthermore, RR and HR measurements of the male groups were more accurate than those of the female groups. CONCLUSIONS We demonstrated that non-contact SIL radar could be used to accurately measure HR and RR for hospital healthcare during the COVID-19 pandemic.


Assuntos
COVID-19 , Processamento de Sinais Assistido por Computador , Masculino , Humanos , Feminino , Radar , Taiwan/epidemiologia , Pandemias , Sinais Vitais , Frequência Cardíaca , Taxa Respiratória , Hospitais , Algoritmos , Monitorização Fisiológica/métodos
5.
Gene ; 865: 147331, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36871674

RESUMO

Slow skeletal muscle troponin T (TNNT1) as a poor prognostic indicator is upregulated in colon and breast cancers. However, the role of TNNT1 in the disease prognosis and biological functions of hepatocellular carcinoma (HCC) is still unclear. The Cancer Genome Atlas (TCGA), real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to evaluate the TNNT1 expression of human HCC. The impact of TNNT1 levels on disease progression and survival outcome was studied using TCGA analysis. Moreover, the bioinformatics analysis and HCC cell culture were used to investigate the biological functions of TNNT1. Besides, the immunoblot analysis and enzyme-linked immunosorbent assay (ELISA) were used to detect the extracellular TNNT1 of HCC cells and circulating TNNT1 of HCC patients, respectively. The effect of TNNT1 neutralization on oncogenic behaviors and signaling was further validated in the cultured hepatoma cells. In this study, tumoral and blood TNNT1 was upregulated in HCC patients based on the analyses using bioinformatics, fresh tissues, paraffin sections, and serum. From the multiple bioinformatics tools, the TNNT1 overexpression was associated with advanced stage, high grade, metastasis, vascular invasion, recurrence, and poor survival outcome in HCC patients. By the cell culture and TCGA analyses, TNNT1 expression and release were positively correlated with epithelial-mesenchymal transition (EMT) processes in HCC tissues and cells. Moreover, TNNT1 neutralization suppressed oncogenic behaviors and EMT in hepatoma cells. In conclusion, TNNT1 may serve as a non-invasive biomarker and drug target for HCC management. This research finding may provide a new insight for HCC diagnosis and treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Músculo Esquelético/metabolismo , Prognóstico , Troponina T/genética
6.
Environ Pollut ; 327: 121476, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36997141

RESUMO

Plasticizers are considered as environmental pollution released from medical devices and increased potential oncogenic risks in clinical therapy. Our previous studies have shown that long-term exposure to di-ethylhexyl phthalate (DEHP)/mono-ethylhexyl phthalate (MEHP) promotes chemotherapeutic drug resistance in colorectal cancer. In this study, we investigated the alteration of glycosylation in colorectal cancer following long-term plasticizers exposure. First, we determined the profiles of cell surface N-glycomes by using mass spectrometry and found out the alterations of α2,8-linkages glycans. Next, we analyzed the correlation between serum DEHP/MEHP levels and ST8SIA6 expression from matched tissues in total 110 colorectal cancer patients. Moreover, clinical specimens and TCGA database were used to analyze the expression of ST8SIA6 in advanced stage of cancer. Finally, we showed that ST8SIA6 regulated stemness in vitro and in vivo. Our results revealed long-term DEHP/MEHP exposure significantly caused cancer patients with poorer survival outcome and attenuated the expression of ST8SIA6 in cancer cells and tissue samples. As expected, silencing of ST8SIA6 promoted cancer stemness and tumorigenicity by upregulating stemness-associated proteins. In addition, the cell viability assay showed enhanced drug resistance in ST8SIA6 silencing cells treated with irinotecan. Besides, ST8SIA6 was downregulated in the advanced stage and positively correlated with tumor recurrence in colorectal cancer. Our results imply that ST8SIA6 potentially plays an important role in oncogenic effects with long-term phthalates exposure.


Assuntos
Neoplasias Colorretais , Dietilexilftalato , Humanos , Plastificantes/análise , Dietilexilftalato/análise , Glicosilação , Sialiltransferases/metabolismo
7.
J Biol Chem ; 298(10): 102442, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36055405

RESUMO

Leukocyte cell-derived chemotaxin 2 (LECT2) acts as a tumor suppressor in hepatocellular carcinoma (HCC). However, the antineoplastic mechanism of LECT2, especially its influence on hepatic cancer stem cells (CSCs), remains largely unknown. In The Cancer Genome Atlas cohort, LECT2 mRNA expression was shown to be associated with stage, grade, recurrence, and overall survival in human HCC patients, and LECT2 expression was downregulated in hepatoma tissues compared with the adjacent nontumoral liver. Here, we show by immunofluorescence and immunoblot analyses that LECT2 was expressed at lower levels in tumors and in poorly differentiated HCC cell lines. Using functional assays, we also found LECT2 was capable of suppressing oncogenic behaviors such as cell proliferation, anchorage-independent growth, migration, invasiveness, and epithelial-mesenchymal transition in hepatoma cells. Moreover, we show exogenous LECT2 treatment inhibited CSC functions such as tumor sphere formation and drug efflux. Simultaneously, hepatic CSC marker expression was also downregulated, including expression of CD133 and CD44. This was supported by infection with adenovirus encoding LECT2 (Ad-LECT2) in HCC cells. Furthermore, in animal experiments, Ad-LECT2 gene therapy showed potent efficacy in treating HCC. We demonstrate LECT2 overexpression significantly promoted cell apoptosis and reduced neovascularization/CSC expansion in rat hepatoma tissues. Mechanistically, we showed using immunoblot and immunofluorescence analyses that LECT2 inhibited ß-catenin signaling via the suppression of the hepatocyte growth factor/c-MET axis to diminish CSC properties in HCC cells. In summary, we reveal novel functions of LECT2 in the suppression of hepatic CSCs, suggesting a potential alternative strategy for HCC therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Ratos , Terapia Genética
8.
Genes (Basel) ; 13(4)2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35456435

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common RCC subtype with a high mortality. It has been reported that delta-like 1 homologue (DLK1) participates in the tumor microenvironmental remodeling of ccRCC, but the relationship between delta-like 2 homologue (DLK2, a DLK1 homologue) and ccRCC is still unclear. Thus, this study aims to investigate the role of DLK2 in the biological function and disease prognosis of ccRCC using bioinformatics analysis. The TNMplot database showed that DLK2 was upregulated in ccRCC tissues. From the UALCAN analysis, the overexpression of DLK2 was associated with advanced stage and high grade in ccRCC. Moreover, the Kaplan-Meier plotter (KM Plotter) database showed that DLK2 upregulation was associated with poor survival outcome in ccRCC. By the LinkedOmics analysis, DLK2 signaling may participated in the modulation of ccRCC extracellular matrix (ECM), cell metabolism, ribosome biogenesis, TGF-ß signaling and Notch pathway. Besides, Tumor Immune Estimation Resource (TIMER) analysis showed that the macrophage and CD8+ T cell infiltrations were associated with good prognosis in ccRCC patients. Finally, DLK2 overexpression was associated with the reduced macrophage recruitments and the M1-M2 polarization of macrophage in ccRCC tissues. Together, DLK2 may acts as a novel biomarker, even therapeutic target in ccRCC. However, this study lacks experimental validation, and further studies are required to support this viewpoint.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Biologia Computacional , Feminino , Humanos , Neoplasias Renais/metabolismo , Masculino , Prognóstico
9.
J Pers Med ; 12(3)2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35330401

RESUMO

Sialylation of glycoproteins is modified by distinct sialyltransferases such as ST3Gal, ST6Gal, ST6GalNAc, or ST8SIA with α2,3-, α2,6-, or α2,8-linkages. Alteration of these sialyltransferases causing aberrant sialylation is associated with the progression of colon cancer. However, among the ST8- sialyltransferases, the role of ST8SIA6 in colon cancer remains poorly understood. In this study, we explored the involvement of ST8SIA6 in colon cancer using multiple gene databases. The relationship between ST8SIA6 expression and tumor stages/grades was investigated by UALCAN analysis, and Kaplan-Meier Plotter analysis was used to analyze the expression of ST8SIA6 on the survival outcome of colon cancer patients. Moreover, the biological functions of ST8SIA6 in colon cancer were explored using LinkedOmics and cancer cell metabolism gene DB. Finally, TIMER and TISMO analyses were used to delineate ST8SIA6 levels in tumor immunity and immunotherapy responses, respectively. ST8SIA6 downregulation was associated with an advanced stage and poorly differentiated grade; however, ST8SIA6 expression did not affect the survival outcomes in patients with colon cancer. Gene ontology analysis suggested that ST8SIA6 participates in cell surface adhesion, angiogenesis, and membrane vesicle trafficking. In addition, ST8SIA6 levels affected immunocyte infiltration and immunotherapy responses in colon cancer. Collectively, these results suggest that ST8SIA6 may serve as a novel therapeutic target towards personalized medicine for colon cancer.

10.
Phytother Res ; 35(7): 3954-3967, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33825221

RESUMO

Microalgae extracts have shown antitumor activities. However, the antitumor mechanism of them is not yet completely clear, especially the effect on cancer stem cells (CSCs). This study aimed to elucidate the antitumor activity and mechanism of microalgal extract from thermotolerant Coelastrella sp. F50 (F50) in hepatocellular carcinoma (HCC). Oncogenic behaviors were analyzed using cell proliferation, colony formation, invasion, sphere formation, and side population cells (SPCs) assays in HCC cells after F50 treatment. The molecular mechanism was further studied by quantitative real-time PCR, immunoblot, and immunofluorescence analyses. The chemopreventive efficacy of F50 was evaluated in rat orthotopic hepatoma, and the hepatic pathologies were investigated by immunohistochemical, immunoblot, and immunofluorescence analyses. F50 specifically suppressed hepatic CSCs (tumor spheres, drug efflux, CD133/ABCG2 CSCs markers) with no cytotoxicity in vitro. In the animal experiments, prophylactic F50 administration significantly attenuated tumor progression and improved liver function in HCC-bearing rats. In the mechanistic analysis, F50 potentially inhibited cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2 ) axis in HCC cells and rat hepatoma, and exogenous PGE2 restored CSCs properties in F50-treated HCC cells. In summary, F50 extract inhibits hepatic CSCs by COX-2/PGE2 downregulation and may facilitate a novel phytotherapy for HCC prevention.


Assuntos
Carcinoma Hepatocelular , Clorofíceas/química , Neoplasias Hepáticas , Células-Tronco Neoplásicas/efeitos dos fármacos , Extratos Vegetais , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Hepáticas/tratamento farmacológico , Microalgas/química , Extratos Vegetais/farmacologia , Ratos
11.
Int J Mol Sci ; 22(8)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920454

RESUMO

Liver cancer remains a leading cause of death, despite advances in anti-cancer therapies. To develop novel drugs, natural products are being considered as a good source for exploration. In this study, a natural product isolated from a soft coral was applied to evaluate its anti-cancer activities in hepatocellular carcinoma SK-HEP-1 cells. Sinularin was determined to have half-maximal inhibitory concentration (IC50) values of ~10 µM after 24, 48, and 72 h. The TUNEL assay and annexin V/PI staining results showed that sinularin induced DNA fragmentation and apoptosis, respectively. An investigation at the molecular level demonstrated that the expression levels of cleaved caspases 3/9 were significantly elevated at 10 µM sinularin. Mitochondrial and intracellular reactive oxygen species (ROS) levels were significantly increased following sinularin treatment, which also affected the mitochondrial membrane potential. In addition, it significantly lowered the mitochondrial respiration parameters and extracellular acidification rates at 10 µM. Further investigation showed that sinularin significantly attenuated wound healing, cell migration, and potential colony formation at 10 µM. Fluorescence microscopic observations showed that the distribution of F-actin filaments was significantly altered at 10 µM sinularin. Supported by Western blot analyses, the expression levels of AKT, p-ERK (extracellular-signal-related kinase), vimentin and VEGF were significantly down-regulated, whereas p-p38, pJNK and E-cadherin were significantly increased. Overall, at the IC50 concentration, sinularin was able to significantly affect SK-HEP-1 cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular , Citoesqueleto/metabolismo , Diterpenos/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Neoplasias Hepáticas , Mitocôndrias Hepáticas/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Citoesqueleto/patologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias Hepáticas/patologia , Ratos
12.
Mar Drugs ; 19(2)2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33572535

RESUMO

Briareum stechei is proven to be a rich source of 3,8-cyclized cembranoids (briarane) with a bicyclo[8.4.0] carbon core. In the present study, four previously unreported briaranes, briarenols W-Z (1-4), along with solenolide A (5), briarenolide M (6), briaexcavatolide F (7), and brianolide (8), were isolated and characterized through spectroscopic analysis, and the absolute configuration of 8 was corroborated by a single-crystal x-ray diffraction analysis. Briaranes 2 and 5 were found to induce significant inflammatory activity in lipopolysaccharide (LPS)-induced RAW 264.7 mouse macrophage cells by enhancing the expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins.


Assuntos
Antozoários/química , Diterpenos/isolamento & purificação , Animais , Cloro , Diterpenos/química , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Células RAW 264.7
13.
FASEB J ; 34(12): 16163-16178, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33063394

RESUMO

Hepatitis is an important health problem worldwide. Novel molecular targets are in demand for detection and management of hepatitis. Hepatoma-derived growth factor (HDGF) has been delineated to participate in hepatic fibrosis and liver carcinogenesis. However, the relationship between hepatitis and HDGF remains unclear. This study aimed to elucidate the role of HDGF during hepatitis using concanavalin A (ConA)-induced hepatitis model. In cultured hepatocytes, ConA treatment-elicited HDGF upregulation at transcriptional level and promoted HDGF secretion while reducing intracellular HDGF protein level and cellular viability. Similarly, mice receiving ConA administration exhibited reduced hepatic HDGF expression and elevated circulating HDGF level, which was positively correlated with serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. By using HDGF knockout (KO) mice, it was found the ConA-evoked cell death was prominently alleviated in KO compared with control. Besides, it was delineated HDGF ablation conferred protection by suppressing the ConA-induced neutrophils recruitment in livers. Above all, the ConA-mediated activation of tumor necrosis factor-α (TNF-α)/interleukin-1ß (IL-1ß)/interleukin-6 (IL-6)/cyclooxygenase-2 (COX-2) inflammatory signaling was significantly abrogated in KO mice. Treatment with recombinant HDGF (rHDGF) dose-dependently stimulated the expression of TNF-α/IL-1ß/IL-6/COX-2 in hepatocytes, further supporting the pro-inflammatory function of HDGF. Finally, application of HDGF antibody not only attenuated the ConA-mediated inflammatory cascade in hepatocytes, but also ameliorated the ConA-induced hepatic necrosis and AST elevation in mice. In summary, HDGF participates in ConA-induced hepatitis via neutrophils recruitment and may constitute a therapeutic target for acute hepatitis.


Assuntos
Concanavalina A/farmacologia , Hepatite Animal/induzido quimicamente , Hepatite Animal/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos
14.
Nucleic Acids Res ; 40(1): 314-22, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21908394

RESUMO

In eukaryotes, the cytoplasmic and mitochondrial forms of a given aminoacyl-tRNA synthetase (aaRS) are typically encoded by two orthologous nuclear genes, one of eukaryotic origin and the other of mitochondrial origin. We herein report a novel scenario of aaRS evolution in yeast. While all other yeast species studied possess a single nuclear gene encoding both forms of alanyl-tRNA synthetase (AlaRS), Vanderwaltozyma polyspora, a yeast species descended from the same whole-genome duplication event as Saccharomyces cerevisiae, contains two distinct nuclear AlaRS genes, one specifying the cytoplasmic form and the other its mitochondrial counterpart. The protein sequences of these two isoforms are very similar to each other. The isoforms are actively expressed in vivo and are exclusively localized in their respective cellular compartments. Despite the presence of a promising AUG initiator candidate, the gene encoding the mitochondrial form is actually initiated from upstream non-AUG codons. A phylogenetic analysis further revealed that all yeast AlaRS genes, including those in V. polyspora, are of mitochondrial origin. These findings underscore the possibility that contemporary AlaRS genes in V. polyspora arose relatively recently from duplication of a dual-functional predecessor of mitochondrial origin.


Assuntos
Alanina-tRNA Ligase/genética , Proteínas Fúngicas/genética , Duplicação Gênica , Genes Fúngicos , Proteínas Mitocondriais/genética , Saccharomycetales/enzimologia , Saccharomycetales/genética , Alanina-tRNA Ligase/metabolismo , Sequência de Aminoácidos , Pareamento de Bases , Sequência de Bases , Núcleo Celular/genética , Códon de Iniciação , Evolução Molecular , Proteínas Fúngicas/metabolismo , Genes Mitocondriais , Proteínas Mitocondriais/metabolismo , Dados de Sequência Molecular , RNA de Transferência de Alanina/química
15.
J Biol Chem ; 284(2): 818-27, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-19010786

RESUMO

Earlier studies showed that the redundancy of ACG initiation codons enhanced the efficiency of translation initiation by 3- to 6-fold. Evidence presented here shows that this "redundancy effect" can be attributed to a favorable sequence context and, to a lesser extent, remedial initiation. In the case of redundant ACG initiator codons, the second ACG not only acts as a remedial initiation site for scanning ribosomes that skip the first ACG but also enhances the activity of the preceding initiator by providing a preferable "A" at its relative +4 position. Hence, non-successive ACG codons can be as effective as successive ACG codons in initiation, if positioned within a similar context. In contrast, redundant GUG initiation codons (GUG/GUG) bear an unfavorable "G" nucleotide at both the +4 and -3 positions relative to the first and second GUGs, respectively, such that redundant GUG codons act more poorly as translation initiation sites than does a single GUG with a favorable "A" nucleotide in the +4 position ( approximately 2.5-fold). Thus, the sequence context plays a much more important role than remedial initiation in modulating the efficiency of translational initiation from redundant non-AUG codons.


Assuntos
Códon de Iniciação/genética , Mitocôndrias/metabolismo , Nucleotídeos/genética , Biossíntese de Proteínas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
16.
Hepatogastroenterology ; 49(47): 1262-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12239920

RESUMO

BACKGROUND/AIMS: Constipation is the most common digestive complaint. Radionuclide colon transit study is a useful tool for assessing the motility of the colon. In this study, we evaluate patients with idiopathic constipation using the radionuclide colon transit study. METHODOLOGY: We studied radionuclide colon transit in 23 patients with idiopathic constipation. Thirty healthy volunteers were included as a control. RESULTS: Overall, patients with idiopathic constipation usually had slow or normal colon transit. CONCLUSIONS: Our study suggested that the radionuclide colon transit study may be clinically useful in evaluating and assessing the efficacy of therapy in patients with idiopathic constipation.


Assuntos
Constipação Intestinal/diagnóstico por imagem , Trânsito Gastrointestinal , Compostos Radiofarmacêuticos , Pentetato de Tecnécio Tc 99m , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia
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