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1.
Front Pharmacol ; 13: 891648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873585

RESUMO

Background: There is a substantial lack of tacrolimus pharmacokinetic information in pediatric hematopoietic stem cell transplant (HSCT) patients. This study aimed to develop population pharmacokinetics (PopPK) of tacrolimus in pediatric HSCT patients and to devise model-guided dosage regimens. Methods: A retrospective analysis was performed on 86 pediatric HSCT patients who received tacrolimus intravenously or orally. A total of 578 tacrolimus trough concentrations (C0) were available for pharmacokinetic analysis using a non-linear mixed-effects modeling method. Demographic and clinical data were included and assessed as covariates via the stepwise method. Bayesian estimators were used to devise pediatric dosage regimens that targeted C0 of 5-15 ng mL-1. Results: A one-compartment model with first-order absorption adequately described the tacrolimus pharmacokinetics. Clearance (CL), volume of distribution (V), and typical bioavailability (F) in this study were estimated to be 2.42 L h-1 (10.84%), 79.6 L (16.51%), and 19% (13.01%), respectively. Body weight, hematocrit, post-transplantation days, and caspofungin and azoles concomitant therapy were considered significant covariates for tacrolimus CL. Hematocrit had a significant impact on the V of tacrolimus. In the subgroup cohort of children (n = 24) with CYP3A5 genotype, the clearance was 1.38-fold higher in CYP3A5 expressers than in non-expressers. Simulation indicated that the initial dosage optimation of tacrolimus for intravenous and oral administration was recommended as 0.025 and 0.1 mg kg-1 d-1 (q12h), respectively. Conclusion: A PopPK model for tacrolimus in pediatric HSCT patients was developed, showing good predictive performance. Model-devised dosage regimens with trough tacrolimus concentrations provide a practical strategy for achieving the therapeutic range.

2.
Theriogenology ; 157: 449-457, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32882647

RESUMO

Oocytes of better quality and developmental competence are highly demanded, which is affected by many intrinsic and external factors, including environmental pollutants. We have previously demonstrated that 7, 12-dimethylbenz [a]anthracene (DMBA) reduces the developmental competence of porcine oocytes, by desynchronizing nuclear and ooplasmic maturation. However, the underlying molecular mechanism remains obscure. Here we performed single cell RNA-seq to study the transcriptome changes in DMBA-treated porcine MII oocytes, and identified 19 protein-coding genes and 156 novel long non-coding RNAs (lncRNAs) with abundance to be significantly different (P < 0.05), which enriched in signaling pathways such as glycosphingolipid biosynthesis, nicotine addiction, basal transcription factors and nucleotide excision repair. RT-qPCR on oocyte pools confirmed ornithine aminotransferase (Oat) and serine/arginine-rich splicing factor 4 (Srsf4) to be significantly up- and down-regulated, respectively (P < 0.05). Treating porcine COCs with MAPK and PLC pathway inhibitors suppressed DMBA's effects on increasing PB1 extrusion rate. In addition, DMBA co-incubation with 250 µM vitamin C derivative (l-ascorbic acid 2-phosphate sesquimagnesium salt hydrate, AA2P) and 100 µM co-enzyme Q10 (CoQ10) could significantly reduce the DMBA-induced high ROS level, and partially alleviate the DMBA-induced high PB1 rate, whereas the cleavage and blastocyst rates of parthenotes derived from treated mature oocytes remained to be low. Collectively, our findings indicate that single cell RNA-seq can help reveal the dynamics of molecular signaling pathways for porcine oocytes treated by DMBA, and supplement of anti-oxidative reagents could not sufficiently rescue DMBA-induced defects of porcine oocytes.


Assuntos
Células do Cúmulo , Oócitos , Animais , Antracenos , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oogênese , RNA-Seq/veterinária , Suínos
3.
Drug Des Devel Ther ; 14: 1535-1545, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368012

RESUMO

BACKGROUND: The efficacy of traditional therapeutic methods for liver cancer is unsatisfying because of the poor targeting, and inefficient drug delivery system. A recent study has proven that aptamers, developed through cell-SELEX, could specifically recognize cancer cells and show great potential in the development of a delivery system for anticancer drugs. PURPOSE: To develop a hepatocellular carcinoma specific aptamer using two kinds of hepatocellular carcinoma cell lines, HepG2 and SMMC-7721, as double targets and a normal hepatocyte, L02, as a negative control cell. METHODS: Hepatocellular carcinoma specific aptamer was developed via cell-SELEX. The enrichment of the library was monitored by flow cytometric analysis. The specificity, affinity, and distribution of the candidate aptamer were explored. Further study was carried to assess its potential in drug delivery. RESULTS: The library was enriched after 14 rounds of screening. Candidate aptamer Apt-07S can recognize four kinds of hepatocellular carcinoma cells and show little cell-binding ability to normal cells and four cell lines of different cancer types, revealing a high specificity of Apt-07S. Confocal imaging showed that Apt-07S distributed both on the surface and in the cytoplasm of the two target cells. Moreover, an anti-sense nucleotide to gene Plk1 (ASO-Plk1) was connected at the 3' end of Apt-07S to form an integrated molecule (Apt-07S-ASO-Plk1); the functional analysis indicated that the structure of Apt-07S may help ASO-Plk1 enter the cancer cells. CONCLUSION: The study indicates that Apt-07S can specifically target HCC and may have potential in the delivery of anticancer drugs.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Técnica de Seleção de Aptâmeros , Aptâmeros de Nucleotídeos/química , Carcinoma Hepatocelular/patologia , Linhagem Celular , Relação Dose-Resposta a Droga , Biblioteca Gênica , Humanos , Neoplasias Hepáticas/patologia , Relação Estrutura-Atividade
4.
Theriogenology ; 121: 160-167, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30165304

RESUMO

Oocyte meiosis is a complex process coordinated by multiple endocrinal and molecular circuits. Recently, N6-methyladenosine (m6A) epigenetic modification on RNA is revealed to be important for meiotic maturation. However, the molecular mechanism of how m6A modification exerts its effect on oocyte maturation is largely unknown. Here, we showed that endogenous m6A writers (Mettl3 and Wtap) and eraser (Fto) elevated their transcript levels during meiotic maturation of pig oocytes. From germinal vesicle (GV) to metaphase II (MII) stages, global m6A level significantly increased, and existed mostly in ooplasm. Methyl donor (betaine, 16 mM) treatment of porcine cumulus-oocyte complexes (COCs) during in vitro maturation (IVM) significantly boosted nucleic acid m6A level within oocytes, but unchanged meiotic process and oocyte subsequent development. By contrast, methylation inhibitor (cycloleucine, 20 mM) reduced nucleic acid m6A level, and significantly decreased the germinal vesicle breakdown (GVBD) rate, the extrusion rate of the first polar body, and the cleavage and blastocyst rates of parthenotes. In addition, in cycloleucine-treated oocytes Wtap increased but Lin28 decreased their abundances significantly, along with the higher incidence of spindle defects and chromosome misalignment. Furthermore, pT161-CDK1 protein level in pig oocytes was confirmed to be decreased after cycloleucine treatment for 24 h. Taken together, chemical induced reduction of nucleic acid m6A methylation during pig oocyte meiosis could impair meiotic maturation and subsequent development potency, possibly through down-regulating pluripotency marker Lin28 mRNA abundance and disturbing MPF-regulated chromosome/spindle organization.


Assuntos
Metilação de DNA , Oócitos/citologia , Animais , Betaína/farmacologia , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo , Cicloleucina/farmacologia , Meiose/genética , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Suínos/embriologia
5.
J Anim Sci ; 96(8): 3358-3369, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-29800308

RESUMO

Heat shock protein 90 (Hsp90) functions as a molecular chaperone in its interaction with clients to influence multiple cellular and physiological processes. However, our current understanding on Hsp90's relationship with mammalian oocyte maturation is still very limited. Here, we aimed to investigate Hsp90's effect on pig oocyte meiotic maturation. Endogenous Hsp90α was constantly expressed at both mRNA and protein levels in porcine maturing oocytes. Addition of 2 µM 17-allylamino-17-demethoxygeldanamycin (17-AAG), the Hsp90 inhibitor, to in vitro mature cumulus-oocyte complexes (COC) significantly decreased Hsp90α protein level (P < 0.05), delayed germinal vesicle breakdown (GVBD) (P < 0.05), and impeded the first polar body (PB1) extrusion (P < 0.01) of porcine oocytes. 2 µM 17-AAG treatment during in vitro maturation also decreased the subsequent development competence as indicated by the lower cleavage (P < 0.001) and higher fragmentation (P < 0.001) rates of parthenotes, whereas no effects on the percentage and average cell number of blastocysts were found. Immunodepletion of Hsp90α by antibody microinjection into porcine oocytes at germinal vesicle and metaphase II stages induced similar defects of meiotic maturation and parthenote development, to that resulted from 2 µM inhibitor 17-AAG. For oocytes treated by 2 µM 17-AAG, the cytoplasm and membrane actin levels were weakened (P < 0.01), and the spindle assembly was disturbed (P < 0.05), due to decreased p-ERK1/2 level (P < 0.05). However, the mitochondrial function and early apoptosis were not affected, as demonstrated by rhodamine 123 staining and Annexin V assays. Our findings indicate that Hsp90α can couple with mitogen-activated protein kinase to regulate cytoskeletal structure and orchestrate meiotic maturation of porcine oocytes.


Assuntos
Proteínas de Choque Térmico/metabolismo , Técnicas de Maturação in Vitro de Oócitos/veterinária , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Suínos/fisiologia , Animais , Feminino , Oócitos/fisiologia
6.
Sci Rep ; 8(1): 6132, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29666467

RESUMO

L-ascorbic acid (Vitamin C) can enhance the meiotic maturation and developmental competence of porcine oocytes, but the underlying molecular mechanism remains obscure. Here we show the role of ascorbic acid in regulating epigenetic status of both nucleic acids and chromatin to promote oocyte maturation and development in pigs. Supplementation of 250 µM L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (AA2P) during in vitro maturation significantly enhanced the nuclear maturation (as indicated by higher rate of first polar body extrusion and increased Bmp15 mRNA level), reduced level of reactive oxygen species, and promoted developmental potency (higher cleavage and blastocyst rates of parthenotes, and decreased Bax and Caspase3 mRNA levels in blastocysts) of pig oocytes. AA2P treatment caused methylation erasure in mature oocytes on nucleic acids (5-methylcytosine (5 mC) and N 6 -methyladenosine (m6A)) and histones (Histone H3 trimethylations at lysines 27, H3K27me3), but establishment of histone H3 trimethylations at lysines 4 (H3K4me3) and 36 (H3K36me3). During the global methylation reprogramming process, levels of TET2 (mRNA and protein) and Dnmt3b (mRNA) were significantly elevated, but simultaneously DNMT3A (mRNA and protein), and also Hif-1α, Hif-2α, Tet3, Mettl14, Kdm5b and Eed (mRNA) were significantly inhibited. Our findings support that ascorbic acid can reprogram the methylation status of not only DNA and histone, but also RNA, to improve pig oocyte maturation and developmental competence.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Epigênese Genética/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Suínos/crescimento & desenvolvimento , Animais , Proteína Morfogenética Óssea 15/genética , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Feminino , Oócitos/citologia , Oócitos/metabolismo , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Suínos/genética , Suínos/metabolismo
7.
J Biol Chem ; 293(5): 1767-1780, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29222335

RESUMO

The brilliant cresyl blue (BCB) test is used in both basic biological research and assisted reproduction to identify oocytes likely to be developmentally competent. However, the underlying molecular mechanism targeted by the BCB test is still unclear. To explore this question, we first confirmed that BCB-positive porcine oocytes had higher rates of meiotic maturation, better rates of cleavage and development into blastocysts, and lower death rates. Subsequent single-cell transcriptome sequencing on porcine germinal vesicle (GV)-stage oocytes identified 155 genes that were significantly differentially expressed between BCB-negative and BCB-positive oocytes. These included genes such as cdc5l, ldha, spata22, rgs2, paip1, wee1b, and hsp27, which are enriched in functionally important signaling pathways including cell cycle regulation, oocyte meiosis, spliceosome formation, and nucleotide excision repair. In BCB-positive GV oocytes that additionally had a lower frequency of DNA double-strand breaks, the CDC5L protein was significantly more abundant. cdc5l/CDC5L inhibition by short interference (si)RNA or antibody microinjection significantly impaired porcine oocyte meiotic maturation and subsequent parthenote development. Taken together, our single-oocyte sequencing data point to a potential new role for CDC5L in porcine oocyte meiosis and early embryo development, and supports further analysis of this protein in the context of the BCB test.


Assuntos
Proteínas de Ciclo Celular , Sequenciamento de Nucleotídeos em Larga Escala , Meiose/fisiologia , Oócitos/metabolismo , Transcriptoma/fisiologia , Animais , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Feminino , Oócitos/citologia , Suínos
8.
Bioorg Med Chem Lett ; 27(22): 5065-5070, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28964635

RESUMO

In this paper, the inhibition of α-amylase and α-glucosidase by nine pentacyclic triterpenes was determined. For α-amylase inhibitory activity, the IC50 values of ursolic acid, corosolic acid, and oleanolic acid were 22.6±2.4µM, 31.2±3.4µM, and 94.1±6.7µM, respectively. For α-glucosidase inhibition, the IC50 values of ursolic acid, corosolic acid, betulinic acid, and oleanolic acid were 12.1±1.0µM, 17.2±0.9µM, 14.9±1.9µM, and 35.6±2.6µM, respectively. The combination of corosolic acid and oleanolic acid with acarbose showed synergistic inhibition against α-amylase. The combination of the tested triterpenes with acarbose mainly exhibited additive inhibition against α-glucosidase. Kinetic studies revealed that corosolic acid and oleanolic acid showed non-competitive inhibition and acarbose showed mixed-type inhibition against α-amylase. The results provide valuable implications for the triterpenes (ursolic acid, corosolic acid, and oleanolic acid) alone or in combination with acarbose as a therapeutic agent for the treatment of diabetes mellitus.


Assuntos
Acarbose/química , Triterpenos Pentacíclicos/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/química , Acarbose/metabolismo , Sinergismo Farmacológico , Concentração Inibidora 50 , Cinética , Ácido Oleanólico/química , Ácido Oleanólico/metabolismo , Triterpenos Pentacíclicos/metabolismo , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/metabolismo , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
9.
Clin Rheumatol ; 35(12): 2901-2908, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27553386

RESUMO

Environmental factors play an important role in the development of rheumatoid arthritis (RA). Among these factors, smoking is generally considered to be an established risk factor for RA. Data regarding the impact of diet on risk of RA development is limited. This study assessed the impact of dietary patterns on RA susceptibility in Chinese populations. This was a large scale, case-control study composed of 968 patients with RA and 1037 matched healthy controls. Subjects were recruited from 18 teaching hospitals. Socio-demographic characteristics and dietary intakes 5 years prior to the onset of RA were reported by a self-administered questionnaire. Differences in quantity of consumption between cases and controls were analyzed by Student's t test. Multiple logistic regression analysis was applied to identify independent dietary risk factor(s) responsible for RA susceptibility. Compared to healthy individuals, RA patients had decreased consumption of mushrooms (P = 0.000), beans (P = 0.006), citrus (P = 0.000), poultry (P = 0.000), fish (P = 0.000), edible viscera (P = 0.018), and dairy products (P = 0.005). Multivariate analyses revealed that several dietary items may have protective effects on RA development, such as mushrooms (aOR = 0.669; 95%CI = 0.518-0.864, P = 0.002), citrus fruits (aOR = 0.990; 95%CI = 0.981-0.999, P = 0.04), and dairy products (aOR = 0.921; 95%CI 0.867-0.977, P = 0.006). Several dietary factors had independent effects on RA susceptibility. Dietary interventions may reduce the risk of RA.


Assuntos
Artrite Reumatoide/epidemiologia , Dieta , Adulto , Idoso , Artrite Reumatoide/diagnóstico , Povo Asiático , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Progressão da Doença , Exposição Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Análise de Regressão , Fatores de Risco , Fumar , Adulto Jovem
10.
Int J Mol Med ; 36(3): 857-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26178664

RESUMO

Multipotent mesenchymal stem cells (MSCs) are widely used as seed cells in studies of tissue engineering and regenerative medicine; however, their clinical application is limited due to replicative senescence. It has been demonstrated that telomerase expression extends the lifespan and maintains the bone-forming ability of MSCs; however, the detailed role and the underlying molecular mechanisms in MSCs remain largely unknown. In the present study, we found that senescence was associated with human telomerase reverse transcriptase (hTERT) expression, and telomere length and telomerase activity. We established a short interfering RNA (siRNA) targeting hTERT and a gene expression vector carrying hTERT and transfected these into the MSCs to investigate the detailed role and the underlying molecular mechanisms of action of hTERT in MSCs. We found that the downregulation of hTERT by siRNA markedly decreased telomere length and telomerase activity in the MSCs, whereas the overexpression of hTERT increased telomere length and telomerase activity in the MSCs. The downregulation of hTERT inhibited cell proliferation and promoted the senescence and apoptosis of MSCs, whereas the upregulation of hTERT increased cell proliferation and decreased the senescence and apoptosis of MSCs. Of note, we also found that the activation of the PI3K/AKT signaling pathway was mediated by hTERT and that blocking this pathway using LY294002 inhibited hTERT expression, induced senescence and decreased the proliferation of MSCs. These findings reveal a previously unknown regulatory mechanism of hTERT, indicating that hTERT mediates the senescence of MSCs through the PI3K/AKT signaling pathway.


Assuntos
Senescência Celular , Células-Tronco Mesenquimais/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Telomerase/metabolismo , Animais , Apoptose , Proliferação de Células , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Ratos Sprague-Dawley , Telomerase/genética , Telômero/metabolismo , Transfecção
11.
Zhong Yao Cai ; 37(6): 998-1000, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25470967

RESUMO

OBJECTIVE: To study the chemical constituents in the hypoglycemic active fraction of Celastrus orbiculatus leaf. METHODS: The constituents were separated and purified by column chromatography and thin layer chromatography, and their structures were elucidated by IR, MS and NMR. RESULTS: Seven compounds were isolated from the active fraction of Celastnrus orbiculatus, which identified as kaempferol( 1) ,quercetin(2), kaempferol-7-0-α-L-rhamnoside (3), kaempferol-3,7-di-O-α-L-rhamnoside (4) , quercetin-3-0-ß-D-glucoside(5), myricetrin(6) and kaempferol-3-0-rutinoside(7). CONCLUSIONS: Chemical constituents in the hypoglycemic active fraction of Celastrus orbiculatus leaf are reported for the first time,and compounds 5,6 and 7 are firstly obtained from this plant.


Assuntos
Celastrus/química , Hipoglicemiantes/isolamento & purificação , Glucosídeos , Quempferóis , Folhas de Planta/química , Quercetina
12.
Breed Sci ; 64(2): 156-63, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24987302

RESUMO

A two-step method was developed to evaluate potato resistance to black scurf caused by Rhizoctonia solani. Tuber piece inoculum was first conducted in the laboratory, which was also first reported in this study. After inoculation with pathogen discs and culture for 48 h, the necrotic spots on the inoculated potato pieces were generated and measured by the crossing method. Further evaluation was conducted through field experiments using a wheat bran inoculum method. The wheat bran inoculum was placed into the pit dispersedly and surrounded seed tubers. Each cultivar or line was subjected to five treatments of 0-, 2-, 3-, 4-, and 5-g soil inoculum. The results showed that 2-4 g of wheat bran inoculum was the optimum for identifying tuber black scurf resistance. The laboratory scores positively correlated with the incidence and severity of black scurf in the field. According to the results in the laboratory, relatively resistant cultivars could be selected for further estimation of tuber black scurf resistance in field experiments. It is a practical and effective screening method for rapid identification of resistant potato germplasm, which can reduce workload in the field, shorten time required for identification.

13.
Exp Ther Med ; 7(5): 1135-1140, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24940399

RESUMO

The aim of this study was to investigate the role of renal Epstein-Barr virus (EBV) infection in the pathogenesis of lupus nephritis (LN). A total of 58 renal tissue samples from patients with LN, seven normal renal tissue samples from patients with non-glomerular hematuria and 37 renal tissue samples from patients with minimal change nephropathy were collected. The expression of EBV-latent membrane protein-1 (EBV-LMP1) and EBV-encoded RNA 1 (EBER-1) in the renal tissue was examined by immunohistochemistry (IHC) and in situ hybridization (ISH), respectively. The sera levels of anti-nuclear antibody as well as antibodies to extractable nuclear antigen in patients with LN were also measured. An equivalence test showed that the results from the IHC and the ISH analyses had strong agreement. The positive rates of renal EBER-1 and EBV-LMP1 in the LN patients were significantly higher than those of the normal and minimal change nephropathy patients (P<0.001), while no significant difference was identified between those of the normal and minimal change nephropathy groups (P>0.05). The positive rates of EBV-LMP1 and EBER-1 in the renal tissues of patients with LN were not determined to be significantly different between the relapse (immunosuppressant-treated) and initial onset (non-treated) patients, between the patients with and without concurrent infection, and among the patients with different age ranges (P>0.05). The proportion of LN patients positive for anti-Sm antibody was significantly higher in the renal EBV-positive group than in the EBV-negative group (P<0.05), while the proportions of LN patients positive for the other autoantibodies that were examined were not identified to be significantly different between these two groups (P>0.05). The present study shows that renal EBV infection may contribute to the pathogenesis of LN by inducing anti-Sm antibody production.

14.
Zhonghua Bing Li Xue Za Zhi ; 39(3): 187-91, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20450767

RESUMO

OBJECTIVE: To investigate the biology of HeLa cells upon inhibition of human telomerase catalytic subunit (hTERT) gene by RNA interference in vitro. METHODS: Four shRNAs (A, B, C and D) targeting hTERT gene were designed and prepared by in-vitro transcription. The expression of hTERT gene was evaluated by immunofluorescent staining and telomeric repeat amplification protocol (TRAP) ELISA (TRAP-ELISA), after transient transfection of shRNAs by lipid formulation. Through the initial selection, shRNA (B) was noticed as the most efficient one in down-regulating hTERT gene and therefore was chosen as the ultimate shRNA used in the experimental groups. Those transfected by non-silencing RNAi were chosen as the control groups. Cell spreading and migration were studied by microscopy and cell adhesion to fibronectin (FN) was assayed by cell counting kit-8 (CCK-8). Cell invasion was assessed by Boyden chamber assay. RESULTS: Cell spreading study revealed that the rates of spreading cells in the experimental groups were (5.6 +/- 2.3)% at 30 min, and (26.3 +/- 6.1)% 2 h after the inoculation, respectively, whereas the rates of spreading cells in the control groups were (31.3 +/- 7.9)% and (79.4 +/- 4.8)%, respectively. There were significant differences between the two groups (P < 0.01). However, most of the cells in both groups became spreading after 24 h. Cell adhesion assay demonstrated that the rate of adhesion cells on FN in experimental groups was (67.2 +/- 2.8)%, less than that in control groups (83.7 +/- 5.4)% (P < 0.05). The relative migration distance was (27.1 +/- 6.2)% in the experimental group, lower than that of the control group (58.7 +/- 15.0)%. The invasion assay revealed that the invading cells were 75.7 +/- 14.5 in the experimental group, in contrast to 165.1 +/- 11.0 in the control group after 4 h incubation on matrigel. The difference between these two groups was significant (P < 0.05). CONCLUSION: In vitro shRNA silencing of hTERT gene can down-regulate the telomerase activity, leading to an inhibition of the malignant phenotype of HeLa cells, including decreased ability of cell spreading and adhesion, reduction of cell migration, and declined invasive ability through Matrige assay.


Assuntos
Adesão Celular , Movimento Celular , Proliferação de Células , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Telomerase/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Invasividade Neoplásica , Telomerase/genética , Transfecção
15.
Zhonghua Bing Li Xue Za Zhi ; 37(5): 323-7, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18956651

RESUMO

OBJECTIVE: To investigate the telomerase activity and to document biological behaviors of HeLa cells upon treatment with specific PI3K/AKT signaling pathway inhibitor, LY294002. METHODS: CCK-8 assay was used to determine IC50 of LY294002. The expressions of total AKT and phosphorylation AKT (P-AKT) were determined using Western blot. Telomerase activity of cell was measured by TRAP-ELISA assay. Cell growth curve, flow cytometry technique and Hoechst33258 stain were used to evaluate the cell growth, cell cycle and apoptosis respectively. Cell migration was determined by cell wound healing assay. RESULTS: IC50 value of LY294002 of treated HeLa cells was 1.73 mg/L. Western blot showed that LY294002 enabled to decrease P-AKT activity in the presence of same total AKT protein. The cell telomerase activity was decreased to 36.72% in contrast to 98.61% of the control. LY294002 decreased the telomerase activity in HeLa cells, and the growth capacity of the cells was significantly suppressed. The number of cells at G0/G1 phases increased to 66.88% compared with that of the control cells (47.36%). The apoptosis rate also increased from 2.4% to 14.9%. The relative migration distance decreased to 24.6% compared with that of control (62.57%). CONCLUSION: LY294002 inhibition of PI3K/AKT signaling pathway leads to alteration of telomerase activity along with changes of the biological behaviors of the HeLa cells suggesting that regulation of telomerase activity may be closely related to PI3K/AKT signaling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromonas/farmacologia , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Transdução de Sinais/efeitos dos fármacos , Western Blotting , Linhagem Celular , Movimento Celular/fisiologia , Inibidores Enzimáticos/farmacologia , Fase G1/efeitos dos fármacos , Células HeLa , Humanos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais/fisiologia , Telomerase
16.
Zhonghua Bing Li Xue Za Zhi ; 36(8): 550-4, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17980104

RESUMO

OBJECTIVE: To investigate biological characteristics of rat bone marrow mesenchymal stem cells (MSC) cultured in vitro and to explore their potential applications. METHODS: MSC were isolated from rat bone marrow by density gradient centrifugation and were induced to differentiation. Flow cytometry was used to characterize their surface antigen expression, cell cycle status and cell growth parameters. Telomerase activity was determined by TRAP-ELISA assay. RESULTS: Fusiform MSC became larger and flattener with increasing passages of culture. After the fourth passage, the MSC showed an immunophenotype of CD29 (94.75% +/- 3.68%), CD71 (95.43% +/- 2.23%), and CD90 (98.08% +/- 3.88%). After the seventh passage, MSC with such immunophenotype decreased with CD29: 50.00% +/- 3.35%, CD71: 50.70% +/- 2.43%, and CD90: 48.60% +/- 2.83%. Cells with such immunoprofile completely disappeared after passage 9. Overall, MSC grew faster during the first 5 passages. The number of MSC in S and G(2)/M phases were 38.36% +/- 2.01% and those in G(0)/G(1) phase were 61.64% +/- 2.13% after 3 passages. The cell growth decreased after passage 7. Percentage of MSCs in S and G(2)/M phases was 10.83% +/- 1.63% and that in G(0)/G(1) was 89.17% +/- 1.96% after passage 12, after which the cells failed to further divide. After passage 9, MSCs lost their ability to differentiate to Von Kossa and oil red O positive staining cells. In addition, telomerase activity of MSC also gradually decreased with the prolonged passages, from the original 52.7% +/- 0.78% to no telomerase activity. CONCLUSION: The biological and immunophenotypical characteristics of cultured MSC showed obvious alterations with increasing numbers of passage of culture.


Assuntos
Células da Medula Óssea/citologia , Proliferação de Células , Células-Tronco Mesenquimais/citologia , Animais , Antígenos CD/metabolismo , Células da Medula Óssea/metabolismo , Ciclo Celular , Diferenciação Celular , Células Cultivadas , Imunofenotipagem , Integrina beta1/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Ratos , Receptores da Transferrina/metabolismo , Antígenos Thy-1/metabolismo
17.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(9): 568-9, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16146609

RESUMO

OBJECTIVE: To investigate the effect of filtration plasmapheresis (DFPP) on blood contents of rheumatoid factor (RF), C reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in patients with rheumatoid arthritis (RA) in active stage, and to appraise the therapeutic effect of DFPP on RA. METHODS: The changes in contents of blood RF, CRP, ESR before and after DFPP were compared. The treatment was given for 2-3 times, and the activity of RA and the appearance of filtrate plasma were compared before and after the treatment. RESULTS: There were dramatic reductions of the levels of RF, CRP, ESR after single DFPP by 22.55%, 57.08% and 50.48%, respectively, compared with those before the treatment (all P<0.001). The color of the filtrate was green in RA in active stage. The cases with dark green filtrate had higher active indexes (pain, tenderness, swelling) and blood contents of CRP and ESR than those with green or yellow-green ones (all P<0.001). CONCLUSION: DFPP can remarkably reduce the level of RF, CRP, ESR of blood. The filtrate of RA in active stage appeared green. There is a relationship between the activity of RA and the color of filtrates.


Assuntos
Artrite Reumatoide/terapia , Troca Plasmática/métodos , Adulto , Idoso , Artrite Reumatoide/sangue , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator Reumatoide/sangue
18.
Am J Physiol Heart Circ Physiol ; 289(4): H1643-51, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15951341

RESUMO

Growth hormone (GH)-releasing peptides (GHRP), a class of synthetic peptidyl GH secretagogues, have been reported to exert a cardioprotective effect on cardiac ischemia. However, whether GHRP have a beneficial effect on chronic heart failure (CHF) is unclear, and the present work aims to clarify this issue. At 9 wk after pressure-overload CHF was created by abdominal aortic banding in rats, one of four variants of GHRP (GHRP-1, -2, and -6 and hexarelin, 100 mug/kg) or saline was injected subcutaneously twice a day for 3 wk. Echocardiography and cardiac catheterization were performed to monitor cardiac function and obtain blood samples for hormone assay. GHRP treatment significantly improved left ventricular (LV) function and remodeling in CHF rats, as indicated by increased LV ejection fraction, LV end-systolic pressure, and diastolic posterior wall thickness and decreased LV end-diastolic pressure and LV end-diastolic dimension. GHRP also significantly alleviated development of cardiac cachexia, as shown by increases in body weight and tibial length in CHF rats. Plasma CA, renin, ANG II, aldosterone, endothelin-1, and atrial natriuretic peptide were significantly elevated in CHF rats but were significantly decreased in GHRP-treated CHF rats. GHRP suppressed cardiomyocyte apoptosis and increased cardiac GH secretagogue receptor mRNA expression in CHF rats. GHRP also decreased myocardial creatine kinase release in hypophysectomized rats subjected to acute myocardial ischemia. We conclude that chronic administration of GHRP alleviates LV dysfunction, pathological remodeling, and cardiac cachexia in CHF rats, at least in part by suppressing stress-induced neurohormonal activations and cardiomyocyte apoptosis.


Assuntos
Caquexia/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Oligopeptídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Caquexia/patologia , Catecolaminas/sangue , Creatina Quinase/metabolismo , Insuficiência Cardíaca/patologia , Hipofisectomia , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Receptores de Grelina , Disfunção Ventricular Esquerda/tratamento farmacológico , Disfunção Ventricular Esquerda/patologia , Remodelação Ventricular/efeitos dos fármacos
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