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1.
Nat Chem Biol ; 15(12): 1223-1231, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31659317

RESUMO

PARP1 inhibitors (PARPi) are known to kill tumor cells via two mechanisms (PARP1 catalytic inhibition and PARP1 trapping). The relative contribution of these two pathways in mediating the cytotoxicity of PARPi, however, is not well understood. Here we designed a series of small molecule PARP degraders. Treatment with one such compound iRucaparib-AP6 results in highly efficient and specific PARP1 degradation. iRucaparib-AP6 blocks the enzymatic activity of PARP1 in vitro, and PARP1-mediated poly-ADP-ribosylation signaling in intact cells. This strategy mimics PARP1 genetic depletion, which enables the pharmacological decoupling of PARP1 inhibition from PARP1 trapping. Finally, by depleting PARP1, iRucaparib-AP6 protects muscle cells and primary cardiomyocytes from DNA-damage-induced energy crisis and cell death. In summary, these compounds represent 'non-trapping' PARP1 degraders that block both the catalytic activity and scaffolding effects of PARP1, providing an ideal approach for the amelioration of the various pathological conditions caused by PARP1 hyperactivation.


Assuntos
Poli(ADP-Ribose) Polimerase-1/metabolismo , Animais , Humanos , Camundongos , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Proteólise
2.
Nucleic Acids Res ; 47(22): 11623-11636, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31647098

RESUMO

Alternative splicing is emerging as an oncogenic mechanism. In prostate cancer, generation of constitutively active forms of androgen receptor (AR) variants including AR-V7 plays an important role in progression of castration-resistant prostate cancer (CRPC). AR-V7 is generated by alternative splicing that results in inclusion of cryptic exon CE3 and translation of truncated AR protein that lacks the ligand binding domain. Whether AR-V7 can be a driver for CRPC remains controversial as the oncogenic mechanism of AR-V7 activation remains elusive. Here, we found that KDM4B promotes AR-V7 and identified a novel regulatory mechanism. KDM4B is phosphorylated by protein kinase A under conditions that promote castration-resistance, eliciting its binding to the splicing factor SF3B3. KDM4B binds RNA specifically near the 5'-CE3, upregulates the chromatin accessibility, and couples the spliceosome to the chromatin. Our data suggest that KDM4B can function as a signal responsive trans-acting splicing factor and scaffold that recruits and stabilizes the spliceosome near the alternative exon, thus promoting its inclusion. Genome-wide profiling of KDM4B-regulated genes also identified additional alternative splicing events implicated in tumorigenesis. Our study defines KDM4B-regulated alternative splicing as a pivotal mechanism for generating AR-V7 and a contributing factor for CRPC, providing insight for mechanistic targeting of CRPC.


Assuntos
Processamento Alternativo/genética , Regulação Neoplásica da Expressão Gênica/genética , Histona Desmetilases com o Domínio Jumonji/genética , Neoplasias de Próstata Resistentes à Castração/genética , Receptores Androgênicos/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Cromatina/metabolismo , Células HEK293 , Humanos , Masculino , Isoformas de Proteínas/genética , Receptores Androgênicos/metabolismo , Spliceossomos/genética
3.
Ann Thorac Surg ; 107(5): 1448-1455, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30552887

RESUMO

BACKGROUND: The pedicled greater omentum has been shown to offer benefit in ischemic heart disease for both animal models and human patients. The impact of cardio-omentopexy in a pressure overload model of left ventricular hypertrophy (LVH) is unknown. METHODS: LVH was created in rats by banding the ascending aorta after right thoracotomy (n = 23). Sham surgery was performed in 12 additional rats. Six weeks after banding, surviving LVH rats were assigned to cardio-omentopexy by left thoracotomy (LVH+Om, n = 8) or sham left thoracotomy (LVH, n = 8). Sham rats also underwent left thoracotomy for cardio-omentopexy (Sham+Om, n = 6); the remaining rats underwent sham left thoracotomy (Sham, n = 6). RESULTS: Echocardiography 10 weeks after cardio-omentopexy revealed LV end-systolic diameter, cardiomyocyte diamter, and myocardial fibrosis in the LVH group were significantly increased compared with the LVH+Om, Sham+Om, and Sham groups (p < 0.01). LV ejection fraction of the LVH group was lower than the LVH+Om group (p < 0.01). Gene expression analysis revealed significantly lower levels of sarcoendoplasmic reticulum calcium adenosine triphosphatase 2b in LVH rats than in the LVH+Om, Sham+Om, and Sham groups (p < 0.01). In contrast, collagen type 1 α 1 chain, lysyl oxidase-like protein 1, nuclear protein-1, and transforming growth factor- ß1 in the LVH group were significantly higher than in the LVH+Om cohort (p < 0.01), consistent with a reduced fibrotic phenotype after omentopexy. Lectin staining showed myocardial capillary density of the LVH group was significantly lower than all other groups (p < 0.01). CONCLUSIONS: Cardio-omentopexy reduced cardiac dilation, contractile dysfunction, cardiomyocyte hypertrophy, and myocardial fibrosis, while maintaining other molecular indicators of contractile function in this LVH model.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Fibrose Endomiocárdica/prevenção & controle , Insuficiência Cardíaca/prevenção & controle , Hipertrofia Ventricular Esquerda/cirurgia , Omento/cirurgia , Animais , Cadeia alfa 1 do Colágeno Tipo I , Modelos Animais de Doenças , Fibrose Endomiocárdica/etiologia , Insuficiência Cardíaca/etiologia , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/patologia , Masculino , Miocárdio , Ratos , Ratos Sprague-Dawley , Volume Sistólico
4.
Nat Commun ; 9(1): 5230, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30531796

RESUMO

Left ventricular hypertrophy (LVH) is a major risk factor for cardiovascular morbidity and mortality. Pathological LVH engages transcriptional programs including reactivation of canonical fetal genes and those inducing fibrosis. Histone lysine demethylases (KDMs) are emerging regulators of transcriptional reprogramming in cancer, though their potential role in abnormal heart growth and fibrosis remains little understood. Here, we investigate gain and loss of function of an H3K9me2 specific demethylase, Kdm3a, and show it promotes LVH and fibrosis in response to pressure-overload. Cardiomyocyte KDM3A activates Timp1 transcription with pro-fibrotic activity. By contrast, a pan-KDM inhibitor, JIB-04, suppresses pressure overload-induced LVH and fibrosis. JIB-04 inhibits KDM3A and suppresses the transcription of fibrotic genes that overlap with genes downregulated in Kdm3a-KO mice versus WT controls. Our study provides genetic and biochemical evidence for a pro-hypertrophic function of KDM3A and proof-of principle for pharmacological targeting of KDMs as an effective strategy to counter LVH and pathological fibrosis.


Assuntos
Cardiomegalia/genética , Regulação da Expressão Gênica/genética , Histona Desmetilases/genética , Miocárdio/metabolismo , Aminopiridinas/farmacologia , Animais , Animais Recém-Nascidos , Cardiomegalia/enzimologia , Células Cultivadas , Fibrose/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Histona Desmetilases/antagonistas & inibidores , Histona Desmetilases/metabolismo , Humanos , Hidrazonas/farmacologia , Camundongos Knockout , Camundongos Transgênicos , Miocárdio/enzimologia , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Ratos Sprague-Dawley
5.
Circulation ; 138(20): 2247-2262, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29853517

RESUMO

BACKGROUND: Cardiac dysfunction is a major component of sepsis-induced multiorgan failure in critical care units. Changes in cardiac autophagy and its role during sepsis pathogenesis have not been clearly defined. Targeted autophagy-based therapeutic approaches for sepsis are not yet developed. METHODS: Beclin-1-dependent autophagy in the heart during sepsis and the potential therapeutic benefit of targeting this pathway were investigated in a mouse model of lipopolysaccharide (LPS)-induced sepsis. RESULTS: LPS induced a dose-dependent increase in autophagy at low doses, followed by a decline that was in conjunction with mammalian target of rapamycin activation at high doses. Cardiac-specific overexpression of Beclin-1 promoted autophagy, suppressed mammalian target of rapamycin signaling, improved cardiac function, and alleviated inflammation and fibrosis after LPS challenge. Haplosufficiency for beclin 1 resulted in opposite effects. Beclin-1 also protected mitochondria, reduced the release of mitochondrial danger-associated molecular patterns, and promoted mitophagy via PTEN-induced putative kinase 1-Parkin but not adaptor proteins in response to LPS. Injection of a cell-permeable Tat-Beclin-1 peptide to activate autophagy improved cardiac function, attenuated inflammation, and rescued the phenotypes caused by beclin 1 deficiency in LPS-challenged mice. CONCLUSIONS: These results suggest that Beclin-1 protects the heart during sepsis and that the targeted induction of Beclin-1 signaling may have important therapeutic potential.


Assuntos
Autofagia , Proteína Beclina-1/metabolismo , Sepse/patologia , Animais , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , PTEN Fosfo-Hidrolase/metabolismo , Sepse/etiologia , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
6.
Asian Pac J Trop Med ; 9(5): 494-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27261861

RESUMO

OBJECTIVE: To discuss the effect and mechanism of miR-34a on the proliferation, apoptosis and invasion of laryngeal carcinoma cells. METHODS: The laryngeal squamous carcinoma Hep2 cells were transiently transfected with miR-34a mimics and miR-34a NC. The MTT, colony-forming assay, Hoechst staining and AnnexinV-PI double staining flow cytometry were employed to detect the effect of miR-34a on the viability and apoptosis of laryngeal squamous carcinoma Hep2 cells; Transwell assay to defect the effect of miR-34a on the migration and invasion of laryngeal squamous carcinoma Hep2 cells; western blot and RT-PCR assay to defect the effect of miR-34a mimics on the expression of survivin and Ki-67 mRNA in laryngeal squamous carcinoma Hep2 cells. RESULTS: Compared with miR-34a NC group, the cell viability in miR-34 mimics group was significantly decreased (P < 0.01), the cell apoptosis rate was significantly increased (P < 0.01), the abilities of cell migration and invasion were significantly reduced (P < 0.01) and the expression of survivin and Ki-67 mRNA was significantly decreased (P < 0.01). CONCLUSIONS: The increased expression of miR-34a can induce the apoptosis of Hep2 laryngeal carcinoma cells and inhibit the cell proliferation and invasion, which is related to the down-regulated expression of survivin and Ki-67.

7.
Chem Biol ; 22(9): 1185-96, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26364928

RESUMO

Histone lysine demethylase KDM4/JMJD2s are overexpressed in many human tumors including prostate cancer (PCa). KDM4s are co-activators of androgen receptor (AR) and are thus potential therapeutic targets. Yet to date few KDM4 inhibitors that have anti-prostate tumor activity in vivo have been developed. Here, we report the anti-tumor growth effect and molecular mechanisms of three novel KDM4 inhibitors (A1, I9, and B3). These inhibitors repressed the transcription of both AR and BMYB-regulated genes. Compound B3 is highly selective for a variety of cancer cell lines including PC3 cells that lack AR. B3 inhibited the in vivo growth of tumors derived from PC3 cells and ex vivo human PCa explants. We identified a novel mechanism by which KDM4B activates the transcription of Polo-like kinase 1 (PLK1). B3 blocked the binding of KDM4B to the PLK1 promoter. Our studies suggest a potential mechanism-based therapeutic strategy for PCa and tumors with elevated KDM4B/PLK1 expression.


Assuntos
Inibidores Enzimáticos/farmacologia , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/biossíntese , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Masculino , Camundongos , Camundongos SCID , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Distribuição Aleatória , Receptores Androgênicos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Quinase 1 Polo-Like
8.
Asian Pac J Trop Med ; 8(8): 636-42, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26321517

RESUMO

OBJECTIVE: To investigate the mechanism of survivin, p53 and Ki-67 on Hep-2 human laryngeal cancer endothelial cell proliferation and invasion. METHODS: Laryngeal squamous cell carcinoma and paracancerous normal tissues were collected, total RNA was extracted from tissues, survivin, p53 and Ki-67 gene mRNA expression levels in laryngeal cancer and the adjacent tissues were detected by Real-time PCR. Human laryngeal cancer Hep-2 epithelial cells were selected, survivin gene was overexpressed, and cell proliferation was detected by MTT. p53 and Ki-67 gene expression changes in overexpressed survivin gene were detected by Western blot. Changes in Hep-2 cell invasive ability were studied when survivin was overexpressed as detected by Transwell invasion assay. RESULTS: In the adjacent tissues, survivin, p53 and Ki-67 gene relative expression levels were 1.72 ± 0.9, 13.7 ± 5.7 and 5.7 ± 1.3, respectively; while in cancer tissues, gene relative expression levels were 53.7 ± 8.3, 66.7 ± 5.2 and 61.0 ± 3.1, respectively, which was significantly increased. As detected by MTT, relative cell survival rate within 12 h of survivin overexpression were: load control group (88.5 ± 1.6)%; overexpressed group (90.3 ± 1.9)%. Transwell invasion assay results indicated that overexpressed survivin could significantly increase the relative survival rate of cells. CONCLUSIONS: Expressions of p53, Ki67 and survivin are increased in cancer; and there is a positive correlation between survivin, p53 and Ki67 expressions in laryngeal carcinoma.

9.
World J Surg Oncol ; 10: 60, 2012 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-22520038

RESUMO

BACKGROUND: The combined effects of anticancer drugs with nutritional factors against tumor cells have been reported previously. This study characterized the efficacy and possible mechanisms of the combination of sorafenib and vitamin K1 (VK1) on glioma cell lines. METHODS: We examined the effects of sorafenib, VK1 or their combination on the proliferation and apoptosis of human malignant glioma cell lines (BT325 and U251) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, flow cytometry and 4',6-diamidino-2-phenylindole (DAPI) assay. The signaling pathway changes were detected by western blotting. RESULTS: Sorafenib, as a single agent, showed antitumor activity in a dose-dependent manner in glioma cells, but the effects were more pronounced when used in combination with VK1 treatment. Sorafenib in combination with VK1 treatment produced marked potentiation of growth inhibition and apoptosis, and reduced expression of phospho-mitogen-activated protein kinase kinase (MEK) and phospho-extracellular signal-regulated kinase (ERK). Furthermore, the expression levels of antiapoptotic proteins Bcl-2 and Mcl-1 were significantly reduced. CONCLUSIONS: Our findings indicated that VK1 enhanced the cytotoxicity effect of sorafenib through inhibiting the Raf/MEK/ERK signaling pathway in glioma cells, and suggested that sorafenib in combination with VK1 maybe a new therapeutic option for patients with gliomas.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Glioma/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Vitamina K 1/farmacologia , Quinases raf/antagonistas & inibidores , Antineoplásicos/farmacologia , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Citometria de Fluxo , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Técnicas Imunoenzimáticas , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Niacinamida/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sorafenibe , Células Tumorais Cultivadas , Vitaminas/farmacologia , Quinases raf/metabolismo
10.
Atherosclerosis ; 219(2): 492-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22005198

RESUMO

OBJECTIVES: FoxO proteins are transcription factors involved in varieties of cellular processes, including immune cell homeostasis, cytokine production, anti-oxidative stress, and cell proliferation and differentiation. Although these processes are implicated in the development of atherosclerosis, very little is known about the role of FoxO proteins in the context of atherosclerosis. Our objectives were to determine whether and how inactivation of Foxo4, a member of the FoxO family, in vivo promotes atherosclerosis. METHODS AND RESULTS: Apolipoprotein E-deficient (apoE(-/-)) mice were crossbred with animals lacking Foxo4 (Foxo4(-/-)). After 10 weeks on a high fat diet (HFD), Foxo4(-/-)apoE(-/-) mice showed elevated atherosclerosis and increased amount of macrophages and T cells in the plaque compared to apoE(-/-) mice. Bone marrow transplantations of chimeric C57B/6 mice reconstituted with either wild-type or Foxo4(-/-) bone marrows indicate that Foxo4-deficiency in bone marrow derived cells sufficiently promoted atherosclerosis. Foxo4-null macrophages produced elevated inflammatory cytokine IL-6 and levels of reactive oxygen species (ROS) in response to lipopolysaccharides in vitro. Serum levels of IL-6 were upregulated in HFD-fed Foxo4(-/-)apoE(-/-) mice compared to those of apoE(-/-) mice. CONCLUSIONS: FoxO4 inhibits atherosclerosis through bone marrow derived cells, possibly by inhibition of ROS and inflammatory cytokines that promote monocyte recruitment and/or retention.


Assuntos
Doenças da Aorta/prevenção & controle , Aterosclerose/prevenção & controle , Células da Medula Óssea/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Animais , Doenças da Aorta/genética , Doenças da Aorta/imunologia , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Células da Medula Óssea/imunologia , Transplante de Medula Óssea , Proteínas de Ciclo Celular , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/deficiência , Fatores de Transcrição Forkhead/genética , Mediadores da Inflamação/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/metabolismo , Transfecção , Quimeras de Transplante
11.
Circ Res ; 109(6): 639-48, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21778425

RESUMO

RATIONALE: Inactivation of the p66Shc adaptor protein confers resistance to oxidative stress and protects mice from aging-associated vascular diseases. However, there is limited information about the negative regulating mechanisms of p66Shc expression in the vascular system. OBJECTIVE: In this study, we investigated the role of SIRT1, a class III histone deacetylase, in the regulation of p66Shc expression and hyperglycemia-induced endothelial dysfunction. METHODS AND RESULTS: Expressions of p66Shc gene transcript and protein were significantly increased by different kinds of class III histone deacetylase (sirtuin) inhibitors in human umbilical vein endothelial cells and 293A cells. Adenoviral overexpression of SIRT1 inhibited high-glucose-induced p66Shc upregulation in human umbilical vein endothelial cells. Knockdown of SIRT1 increased p66Shc expression and also increased the expression levels of plasminogen activator inhibitor-1 expression, but decreased manganese superoxide dismutase expression in high-glucose conditions. However, knockdown of p66Shc significantly reversed the effects of SIRT1 knockdown. In addition, p66Shc overexpression significantly decreased manganese superoxide dismutase expression and increased plasminogen activator inhibitor-1 expression in high-glucose conditions, which were recovered by SIRT1 overexpression. Moreover, compared to streptozotocin-induced wild-type diabetic mice, endothelium-specific SIRT1 transgenic diabetic mice had decreased p66Shc expression at both the mRNA and the protein levels, improved endothelial function, and reduced accumulation of nitrotyrosine and 8-OHdG (markers of oxidative stress). We further found that SIRT1 was able to bind to the p66Shc promoter (-508 bp to -250 bp), resulting in a decrease in the acetylation of histone H3 bound to the p66Shc promoter region. CONCLUSION: Our findings indicate that repression of p66Shc expression by SIRT1 contributes to the protection of hyperglycemia-induced endothelial dysfunction.


Assuntos
Regulação para Baixo/genética , Endotélio Vascular/metabolismo , Hiperglicemia/genética , Proteínas Adaptadoras da Sinalização Shc/antagonistas & inibidores , Sirtuína 1/fisiologia , Envelhecimento/genética , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Endotélio Vascular/patologia , Células HEK293 , Humanos , Hiperglicemia/patologia , Hiperglicemia/prevenção & controle , Imunidade Inata/genética , Masculino , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/genética , Estabilidade Proteica , Proteínas Adaptadoras da Sinalização Shc/biossíntese , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
12.
Stem Cell Rev Rep ; 7(1): 195-207, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20676943

RESUMO

Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs), isolated from discarded extra-embryonic tissue after birth, are promising candidate source of mesenchymal stem cells (MSCs). Apart from their prominent advantages in abundant supply, painless collection, and faster self-renewal, hUC-MSCs have shown the potencies to differentiate into a variety of cells of three germ layers (such as bone, cartilage, adipose, skeletal muscle, cardiomyocyte, endothelium, hepatocyte-like cluster, islet-like cluster, neuron, astrocyte and oligodendrocyte), to synthesize and secret a set of trophic factors and cytokines, to support the expansion and function of other cells (like hematopoietic stem cells, embryonic stem cells, natural killer cells, islet-like cell clusters, neurons and glial cells), to migrate toward and home to pathological areas, and to be readily transfected with conventional methods. Two excellent previous reviews documenting the characteristics of this cell population with special emphasis on its niche, isolation, surface markers and primitive properties have been published recently. In this review, we will firstly give a brief introduction of this cell population, and subsequently dwell on the findings of differential capacities with emphasis on its therapeutic potentials.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Animais , Diferenciação Celular , Doença , Humanos , Imunomodulação , Células-Tronco Mesenquimais/metabolismo
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(9): 1783-6, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19778789

RESUMO

OBJECTIVE: To investigate the mechanism of autologous mesenchymal stem cells (MSCs) in prolonging the survival of dogs receiving living donor liver transplantation. METHODS: Canine models of allogenic living donor liver transplantation was established in 14 beagle dogs by non-venous by-pass method, and in 7 of the recipients, autologous MSCs labeled by BrdU was infused into the portal vein, with the other 7 dogs as the control. The survival time of the two groups of the dogs was observed after the operation. The liver function (AST and ALT levels), liver pathologies and the differentiation of the transplanted cells were also evaluated postoperatively. RESULTS: Compared with the control group, the dogs receiving MSC transplantation showed significantly increased median survival time (P<0.001) with lowered levels of AST and ALT (P<0.01). The two groups exhibited similar graft rejection after the operation. In dogs with MSC transplantation, the BrdU-labeled MSCs differentiated into liver-like cells in the liver and secreted albumin. CONCLUSION: Autologous MSCs infusion through the portal vein during allogenic living donor liver transplantation can prolong the survival of the recipient dogs. The stem cells transplanted can differentiate into mature liver-like cells and secrete albumin in the hepatic tissue.


Assuntos
Sobrevivência de Enxerto , Tolerância Imunológica/imunologia , Transplante de Fígado/imunologia , Transplante de Células-Tronco Mesenquimais , Animais , Cães , Doadores Vivos , Masculino , Distribuição Aleatória
14.
Gastroenterology ; 137(4): 1403-14, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19560465

RESUMO

BACKGROUND & AIMS: FoxO4 is a member of the forkhead box transcription factor O (FoxO) subfamily. FoxO proteins are involved in diverse biological processes. In this study, we examine the role of FoxO4 in intestinal mucosal immunity and inflammatory bowel disease (IBD). METHODS: Foxo4-null mice were subjected to trinitrobenzene sulfonic acid (TNBS) treatment. Microarray analysis and quantitative reverse transcription polymerase chain reaction were used to identify the cytokine transcripts that were altered by Foxo4 deletion. The effects of Foxo4 deficiency on the intestinal epithelial permeability and levels of tight junction proteins were examined by permeable fluorescent dye and Western blot. The molecular and cellular mechanisms by which FoxO4 regulates the mucosal immunity were explored through immunologic and biochemical analyses. The expression level of FoxO4 in intestinal epithelial cells of patients with IBD was examined with immunohistochemistry. RESULTS: Foxo4-null mice were more susceptible to TNBS injury-induced colitis. The chemokine CCL5 is significantly up-regulated in the colonic epithelial cells of Foxo4-null mice, with increased recruitment of CD4(+) intraepithelial T cells and up-regulation of cytokines interferon-gamma and tumor necrosis factor-alpha in the colon. Foxo4 deficiency also resulted in an increase in intestinal epithelial permeability and down-regulation of the tight junction proteins ZO-1 and claudin-1. Mechanistically, FoxO4 inhibited the transcriptional activity of nuclear factor-kappaB (NF-kappaB), and Foxo4 deficiency is associated with increased NF-kappaB activity in vivo. FoxO4 transcription is transiently repressed in response to TNBS treatment and in patients with IBD. CONCLUSION: These results indicate that FoxO4 is an endogenous inhibitor of NF-kappaB and identify a novel function of FoxO4 in the regulation of NF-kappaB-mediated mucosal immunity.


Assuntos
Colite/prevenção & controle , Colo/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Imunidade nas Mucosas , Doenças Inflamatórias Intestinais/prevenção & controle , NF-kappa B/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células CACO-2 , Proteínas de Ciclo Celular , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Colo/imunologia , Colo/patologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/deficiência , Fatores de Transcrição Forkhead/genética , Perfilação da Expressão Gênica/métodos , Humanos , Imunidade nas Mucosas/genética , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/metabolismo , Camundongos , Camundongos Knockout , NF-kappa B/imunologia , NF-kappa B/metabolismo , Permeabilidade , RNA Mensageiro/metabolismo , Transdução de Sinais , Junções Íntimas/imunologia , Junções Íntimas/metabolismo , Fatores de Tempo , Transcrição Gênica , Transfecção , Ácido Trinitrobenzenossulfônico , Regulação para Cima
15.
Cardiovasc Res ; 80(2): 191-9, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18689793

RESUMO

AIMS: Hazardous environmental and genetic factors can damage endothelial cells to induce atherosclerotic vascular disease. Recent studies suggest that class III deacetylase SIRT1 may promote cell survival via novel antioxidative mechanisms. The current study tested the hypothesis that SIRT1, specifically overexpressed in the endothelium, is atheroprotective. METHODS AND RESULTS: Human umbilical vein endothelial cells (HUVECs) were used to study the effects of oxidized low-density lipoprotein (LDL) on SIRT1 expression. Endothelial cell-specific SIRT1 transgenic (SIRT1-Tg) mice were used to study the effects of SIRT1 on aortic vascular tone. SIRT1-Tg mice were crossed with apolipoprotein E null (apoE(-/-)) mice to obtain SIRT1-Tg/apoE(-/-) mice for the analysis of atherogenesis in the presence of endothelial overexpression of SIRT1. SIRT1 expression in HUVECs was increased by the treatment with oxidative LDL. Adenoviral-mediated overexpression of SIRT1 was protective of apoptosis of HUVECs. Calorie restriction increased, whereas high-fat diet decreased, the SIRT1 expression in mouse aortas. In SIRT1-Tg mice, high fat-induced impairment in endothelium-dependent vasorelaxation was improved compared with that of wild-type littermates. This was accompanied by an upregualtion of aortic endothelial nitric oxide synthase expression in the SIRT1-Tg mice. The SIRT1-Tg/apoE(-/-) mice had less atherosclerotic lesions compared with apoE(-/-) controls, without affecting blood lipids and glucose levels. CONCLUSION: These results suggest that endothelium-specific SIRT1 overexpression likely suppresses atherogenesis via improving endothelial cell survival and function.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Endotélio Vascular/enzimologia , Sirtuínas/metabolismo , Animais , Apolipoproteínas E/genética , Apoptose , Aterosclerose/enzimologia , Aterosclerose/etiologia , Aterosclerose/fisiopatologia , Glicemia/metabolismo , Restrição Calórica , Células Cultivadas , Gorduras na Dieta , Modelos Animais de Doenças , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Humanos , Lipídeos/sangue , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III , Sirtuína 1 , Sirtuínas/genética , Regulação para Cima , Vasodilatação
16.
Ai Zheng ; 26(5): 463-8, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17672933

RESUMO

BACKGROUND & OBJECTIVE: Matrix metalloproteinases (MMPs) are key enzymes involved in tumor development, invasion and metastasis. The single nucleotide polymorphisms (SNPs) in the promoter regions of MMP genes may influence tumor development and progression via modulating mRNA transcription and protein expression. This study was to explore the correlations of the promoter SNPs in MMP-3 and MMP-7 genes to susceptibility to brain astrocytoma. METHODS: The genotype of MMP-3 -1171 5A/6A and MMP-7 -181A/G polymorphisms in 236 patients with brain astrocytoma and 366 healthy controls was detected by polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP). RESULTS: The allelotype and overall genotype distribution of MMP-3 SNP among the astrocytoma patients and healthy controls were similar (P>0.05). Stratified by sex, age, and histological grade, the susceptibility to brain astrocytoma among the subjects with 5A/5A and 5A/6A genotypes and the subjects with 6A/6A genotype were similar(P>0.05). The overall genotype distribution of MMP-7 SNP among the astrocytoma patients and healthy controls were significantly different (P = 0.001). Compared with the A/A genotype, both the G/G and the A/G genotypes significantly increased the susceptibility to astrocytoma [sex-and age-adjusted odds ratio (OR) = 2.77 and 1.69, 95% confidence interval (CI)=1.27-6.02 and 1.01-2.84, respectively]. Stratification analysis showed that the G/G genotype significantly increased the susceptibility to astrocytoma in men (adjusted OR = 3.24, 95% CI = 1.12-9.41) and in the individuals younger than 45 years (adjusted OR = 3.16, 95% CI = 1.09-9.16). When stratified by histological grade, the A/G genotype increased the susceptibility to grade II astrocytoma by about 2 folds (adjusted OR = 2.06, 95% CI = 1.05 - 4.05), while the G/G genotype increased the susceptibility to grade II-IV astrocytoma by about 3 folds. CONCLUSION: MMP-7 -181A/G polymorphism may influence the susceptibility to astrocytoma, while MMP-3-1171 5A/6A polymorphism has no correlation to the susceptibility.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Predisposição Genética para Doença , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 7 da Matriz/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Alelos , Astrocitoma/enzimologia , Astrocitoma/patologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Intervalos de Confiança , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas , Adulto Jovem
18.
Beijing Da Xue Xue Bao Yi Xue Ban ; 37(6): 645-7, 2005 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-16378121

RESUMO

OBJECTIVE: To summarize the clinical characteristics and therapeutic experience of optic gliomas. METHODS: The clinical data of 7 patients of our department in the past 3 years were analyzed. RESULTS: In this series of optic glioma patients, the average age was 18.7 years, the ratio of men to women was 4:3, and 100% of the tumors were sub-totally removed. Diabetes inspidus was the most comman postoperative complication. CONCLUSION: The optic glioma is benign intracranial tumor with good prognosis. The key point of treatment is surgical resection combined with proper postoperative radiotherapy.


Assuntos
Microcirurgia/métodos , Glioma do Nervo Óptico/diagnóstico , Glioma do Nervo Óptico/cirurgia , Adolescente , Adulto , Criança , Diabetes Insípido/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Microcirurgia/efeitos adversos , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias , Estudos Retrospectivos
19.
Cell Transplant ; 14(5): 311-21, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16052912

RESUMO

Mesenchymal stem cells (MSCs) have been successfully isolated from a broad range of adult, fetal, and other nonembryonic tissues. Fetal lung has been identified as a rich source of MSCs. However, the biological characteristics and differentiation potential of fetal lung MSCs remain to be explored. In this study, we established a series of methods for isolation and expansion of fetal lung MSCs. These MSCs could withstand more than 40 passages without obvious decline in proliferation ability, significant changes in morphology, and expression of cell markers. Flow cytometric analysis showed that fetal lung MSCs expressed CD13, CD29, CD44, CD90, CD105, CD166, and HLA-ABC, but not CD14, CD31, CD34, CD38, CD41a, CD42b, CD45, CD49d, CD61, CD106, CD133, and HLA-DR. Cell cycle analysis revealed that when the MSCs reached their log phase of growth, more than 90% of the cells were in G0/G1 phase while the proportion of cells in S phase and G2/M phase were about 5.56% and 2.08% cells, respectively. These MSCs could differentiate into neural cells in addition to their mesenchymal differentiation potential. Our data suggest that the fetal lung MSC population is an alternative source of stem cells for cell-based therapy of neurological defects or mesenchymal-originating diseases.


Assuntos
Pulmão/citologia , Pulmão/embriologia , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Adipócitos/citologia , Adesão Celular/fisiologia , Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Separação Celular , Células Cultivadas , Feto/citologia , Fibroblastos/citologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Imunofenotipagem , Mesoderma/citologia , Osteogênese , Fenótipo
20.
Neurosci Lett ; 380(3): 322-5, 2005 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-15862910

RESUMO

Freshly isolated or culture-expanded human umbilical cord blood mononuclear cells (CBMNCs) have been known to express neural phenotypes in vitro and to differentiate into neural cells and improve neurological function recovery after being administrated into rodent models of neurological diseases. However, the mechanism of action remains unclear. The present study observed that CBMNCs expressed higher level mRNAs of several neurotrophic factors than adult peripheral blood mononuclear cells (PBMCs). In addition, a significantly increase in the levels of brain-derived neurotrophic factor (BDNF) and neurotrophin-4/5 (NT4/5) was found in culture supernatants of CBMNCs compared to that of PBMNCs. These findings indicate that CBMNCs express several neurotrophic factors and suggest that the neurotrophic factors secreted by CBMNCs may be responsible for amelioration of central nervous system deficits in animal models after CBMNC administration.


Assuntos
Sangue Fetal/metabolismo , Leucócitos Mononucleares/metabolismo , Fatores de Crescimento Neural/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Sangue Fetal/citologia , Humanos , Recém-Nascido , RNA Mensageiro/metabolismo , Recuperação de Função Fisiológica/fisiologia , Regeneração/fisiologia , Células-Tronco/metabolismo
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