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1.
Oncol Rep ; 30(4): 1996-2002, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23921598

RESUMO

Cordyceps militaris (C. militaris) and its main functional component, cordycepin, has been shown to possess a number of pharmacological activities including immunological stimulation and antitumor effects. However, the pharmacological mechanisms of C. militaris on tumor immunity underlying its antitumor effect have yet to be elucidated. In the present study, we evaluated the antitumor and immunomodulatory effects of C. militaris on FM3A tumor-bearing C3H/He mice, comparing wild-type C. militaris and cordycepin-enriched C. militaris (JLM 0636). The concentration of cordycepin produced by crossbred JLM 0636 was 7.42 mg/g dry weight, which was 7-fold higher than that of wild-type C. militaris. Dietary administration of C. militaris revealed retardation of tumor growth as well as elongation of survival rates of tumor-bearing mice. This effect was more pronounced in JLM 0636. There was a cordycepin-dependent decrease in IL-2 and TGF-ß secretion and an increase in IL-4 secretion without changes in the proliferative responses of concanavalin A-stimulated lymphocytes, which suggested that C. militaris feeding might induce changes in the subpopulations of tumor-derived T lymphocytes. CD4+CD25+ cell population was significantly reduced in the total splenocytes from JLM 0636-administered mice, while CD4+ T cell population remained unchanged. FoxP3+-expressing Treg cells among CD4+CD25+ population showed a similar pattern. On the contrary, CD8+ T cells as well as the IFN-γ expressing CD8+ T cells from tumor-bearing mice were significantly upregulated by the administration of JLM 0636. These results demonstrated the suppressive role of JLM 0636 on the function of Treg cells contributing to tumor specific IFN-γ-expressing CD8+ T cell responses in tumor-bearing mice, which explained the underlying mechanism of the antitumor immunity of cordycepin. Therefore, cordycepin-enriched C. militaris is a promising candidate for an adjuvant in cancer immunotherapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/terapia , Cordyceps/metabolismo , Desoxiadenosinas/farmacologia , Animais , Neoplasias da Mama/genética , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Desoxiadenosinas/genética , Feminino , Fatores de Transcrição Forkhead/metabolismo , Imunomodulação/efeitos dos fármacos , Imunoterapia/métodos , Interferon gama/metabolismo , Interleucina-2/biossíntese , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-4/biossíntese , Interleucina-4/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Taxa de Sobrevida , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/metabolismo
2.
Int J Mol Med ; 31(1): 205-12, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23151809

RESUMO

The control of melanogenesis is an important strategy in the treatment of abnormal skin pigmentation for cosmetic purposes. The aim of the present study was to investigate the anti-melanogenic effect of Asterina pectinifera (A. pectinifera) extracts by cell-free mushroom tyrosinase assay, cellular tyrosinase assay, melanin content assay and the analysis of related protein expression in melan-a cells. A. pectinifera was extracted with 80% methanol (80-MAP) and further fractionated with hexane (He-AP) and ethyl acetate (EA-AP). In addition, the enzyme extract (En-AP) of A. pectinifera, to which protease was added, was processed. EA-AP and En-AP among A. pectinifera extracts showed strong inhibitory activity against the cell-free mushroom tyrosinase activity. EA-AP and En-AP induced significant inhibition of melanin production and cellular tyrosinase activity. In the action of EA-AP and En-AP on melanogenesis, they reduced the expression of melanogenic genes and proteins including tyrosinase, tyrosinase-related protein-1 (TRP-1) and dopachrome tautomerase (Dct). These results showed that EA-AP and En-AP inhibited melanogenesis by reducing tyrosinase activity and melanin production via subsequent downregulation of tyrosinase-related proteins. The overall results suggest that EA-AP and En-AP among A. pectinifera extracts may be promising candidates for the treatment of hyperpigmentation disorder and useful for self-tanning cosmetic products.


Assuntos
Asterina/química , Materia Medica/farmacologia , Melaninas/biossíntese , Melanócitos/efeitos dos fármacos , Monofenol Mono-Oxigenase/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Oxirredutases Intramoleculares/antagonistas & inibidores , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Melaninas/antagonistas & inibidores , Melanócitos/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/genética , Oxirredutases/antagonistas & inibidores , Oxirredutases/genética , Oxirredutases/metabolismo , Pigmentação da Pele/efeitos dos fármacos
3.
Exp Ther Med ; 3(4): 592-598, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22969934

RESUMO

Recent advances in the understanding of the mechanisms responsible for tumor progression suggest the possibility to control cancer growth, not only through chemotherapy-induced cancer cell destruction, but also by stimulating anticancer immunity. However, immune tolerance against tumor antigens disturbs diverse forms of immunotherapy. One of the most potent and well-studied tumor-induced immunosuppressive phenotypes found in the tumor microenvironment is the regulatory subpopulation cells (CD4(+)CD25(+)FoxP3(+) Treg cells). Among the great number of natural agents derived from plants and potentially useful for application in the complementary therapy of cancer, resveratrol is gaining attention for its immunomodulating properties in breast cancer, since the ineffectiveness of numerous immunotherapy strategies may be related, in part, to their negative effects on Treg cells. The present study was undertaken to examine whether HS-1793, a synthetic resveratrol analogue free from the restriction of the metabolic instability and high dose requirement of resveratrol, shows a direct effect on immune responses by enhancing lymphocyte proliferation or an immunomodulatory effect by inducing changes in the Treg cell population in FM3A breast tumor-bearing mice. Although HS-1793 had no direct immunostimulatory effect, it dose-dependently decreased IL-2 secretion and increased IL-4 secretion of concanavalin A-stimulated lymphocytes from tumor-bearing mice, which suggest that HS-1793 may induce changes in the subpopulations of tumor-derived T lymphocytes. The CD4(+)CD25(+) cell population from tumor-bearing mice decreased after HS-1793 treatment in a dose-dependent manner, while the CD4(+) T cell population remained unchanged. FoxP3(+)-expressing cells among the CD4(+)CD25(+) population showed a similar pattern. In contrast, the CD8(+) T cell population as well as the interferon (IFN)-γ-expressing CD8(+) T cell population and IFN-γ secretion of splenocytes from tumor-bearing mice were significantly upregulated by HS-1793 treatment. These results suggest that HS-1793 induces the modulation of tumor-derived T lymphocytes, particulary having a suppressive effect on the Treg cell population, likely contributing to enhanced tumor-specific cytotoxic T lymphocyte responses and CD4(+) T cells involving antitumor immunity. Therefore, HS-1793 may serve as a promising adjuvant therapeutic reagent in breast cancer immunotherapy.

4.
Int Immunopharmacol ; 14(3): 328-33, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22884509

RESUMO

Natural agents with the immunomodulating property have been gaining traction to be employed in the complementary therapy of cancer because the ineffectiveness of numerous therapeutic strategies may be related in part to the tumor-induced immunosuppressive phenotypes, especially regulatory T (Treg) cells found in the tumor microenvironment. The present study was undertaken to examine whether HS-1793, synthetic resvertrol analog free from the restriction of metabolic instability and high dose requirement of resveratrol, induces an in vivo anti-tumor effect in FM3A tumor bearing mice through the suppression of Treg cells, which contribute to an increase in tumor specific cytotoxic T cell responses. Intraperitoneal injections of HS-1793 showed not only therapeutic benefits on established tumors, but also preventive anti-tumor effects. Treg cells (CD4+CD25+Foxp3+ cells) were significantly reduced in the total splenocytes as well as tumor tissues from HS-1793-administered mice, and the production of TGF-ß inducing Treg showed a similar pattern. On the contrary, the administration of HS-1793 increased IFN-γ-expressing CD8+ T cells, upregulated IFN-γ production, and enhanced the cytotoxicity of splenocytes against FM3A tumor cells both in therapeutic and preventive experimental animals. These results demonstrated the suppressive role of HS-1793 on the function of Treg cells contributing to tumor specific cytotoxic T lymphocyte responses in tumor-bearing mice, which explained the underlying mechanism of the anti-tumor immunity of HS-1793.


Assuntos
Antineoplásicos/farmacologia , Naftóis/farmacologia , Neoplasias/imunologia , Resorcinóis/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Camundongos , Camundongos Endogâmicos C3H , Naftóis/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Resorcinóis/uso terapêutico , Baço/citologia , Baço/imunologia , Linfócitos T/imunologia , Carga Tumoral/efeitos dos fármacos
5.
Cardiovasc Res ; 95(4): 495-506, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22886775

RESUMO

AIMS: In this study, our aim was to evaluate the angio-vasculogenic properties of human adipose tissue-derived mesenchymal stem cells overexpressing the granulocyte chemotactic protein (GCP)-2 (hASCs/GCP-2) and to determine possible therapeutic effects in an experimental ischaemic heart model. METHODS AND RESULTS: Quantitative real-time (qRT)-PCR results revealed that hASCs/GCP-2 expressed significantly higher levels of pro-angiogenic genes, including vascular endothelial growth factor (VEGF)-A, hepatocyte growth factor (HGF), and interleukin (IL)-8, when compared with control-vector transduced hASCs or human umbilical vascular endothelial cells (HUVECs). In addition, the anti-apoptotic insulin-like growth factor (IGF)-1 and Akt-1 were also highly up-regulated in the hASCs/GCP-2 cells. In vitro cell migration and proliferation assays showed that hASCs/GCP-2-derived conditioned media (CM) significantly accelerated the migration and proliferation of fibroblast cells. Examination of in vitro endothelial differentiation showed that hASCs/GCP-2 cells spontaneously formed vascular-like structures and highly expressed endothelial-specific genes and proteins. In vivo study results of our mouse myocardial infarction (MI) model revealed that hASCs/GCP-2 implantation improved the cardiac function and reduced the infarct size. Finally, transplanted hASCs/GCP-2 cells unexpectedly differentiated into endothelial cells and the engraftment rate was significantly higher than control groups. CONCLUSION: We suggest that overexpression of GCP-2 in stem cells has the potential to enhance their angiogenic and survival properties.


Assuntos
Quimiocina CXCL6/metabolismo , Terapia Genética/métodos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/terapia , Miocárdio/metabolismo , Neovascularização Fisiológica , Animais , Apoptose , Diferenciação Celular , Linhagem Celular , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Quimiocina CXCL6/genética , Meios de Cultivo Condicionados/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Neovascularização Fisiológica/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Recuperação de Função Fisiológica , Fatores de Tempo , Transfecção , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Toxicol Res ; 28(3): 165-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24278606

RESUMO

Raphanus sativus (Cruciferaceae), commonly known as radish is widely available throughout the world. From antiquity it has been used in folk medicine as a natural drug against many toxicants. The present study was designed to evaluate the hepatoprotective activity of radish (Raphanus sativus) enzyme extract (REE) in vitro and in vivo test. The IC50 values of REE in human liver derived HepG2 cells was over 5,000 µg/ml in tested maximum concentration. The effect of REE to protect tacrine-induced cytotoxicity in HepG2 cells was evaluated by MTT assay. REE showed their hepatoprotective activities on tacrineinduced cytotoxicity and the EC50 value was 1,250 µg/ml. Silymarin, an antihepatotoxic agent used as a positive control exhibited 59.7% hepatoprotective activitiy at 100 µg/ml. Moreover, we tested the effect of REE on carbon tetrachloride (CCl4)-induced liver toxicity in rats. REE at dose of 50 and 100 mg/kg and silymarin at dose of 50 mg/kg were orally administered to CCl4-treated rats. The results showed that REE and silymarin significantly reduced the elevated levels of serum enzyme markers induced by CCl4. The biochemical data were supported by evaluation with liver histopathology. These findings suggest that REE, can significantly diminish hepatic damage by toxic agent such as tacrine or CCl4.

7.
Glia ; 58(16): 1961-76, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20830808

RESUMO

Bortezomib, a proteasome inhibitor, has been considered as a promising anticancer drug in the treatment of recurrent multiple myeloma and some solid tumors. The bortezomib-induced peripheral neuropathy (BIPN) is a prominent cause of dose-limiting toxicities after bortezomib treatment. In this study, we found that BIPN in a mouse model is characterized by acute but transient endoplasmic reticulum (ER) damages to Schwann cells. These damaged Schwann cells exhibit abnormal outcomes from healing processes such as the myelination of Remak bundles. A morphometric analysis of polymyelinated Remak bundles revealed that the pathological myelination was not related to the axonal parameters that regulate the normal myelination process during development. In addition, demyelinating macrophages were focally infiltrated within endoneurium of the sciatic nerve. To identify the mechanism underlying these pathologies, we applied a gene microarray analysis to bortezomib-treated primary Schwann cells and verified the changes of several gene expression in bortezomib-treated sciatic nerves. The analysis showed that bortezomib-induced ER stress was accompanied by the activation of several protective molecular chaperones and the down-regulation of myelin gene expression. ER stress inducers such as thapsigargin and bredelfin A also suppressed the mRNA expression of myelin gene P0 at transcriptional levels. In addition, the expression of chemokines such as the macrophage chemoattractants Ccl3 and Cxcl2 was significantly increased in Schwann cells in response to bortezomib and ER stress inducers. Taken together, these observations suggest that the pathological adaptive responses of Schwann cells to bortezomib-induced ER stress may, in part, participate in the development of BIPN.


Assuntos
Adaptação Fisiológica/fisiologia , Ácidos Borônicos/toxicidade , Retículo Endoplasmático/fisiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Pirazinas/toxicidade , Células de Schwann/fisiologia , Estresse Fisiológico/fisiologia , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Axônios/fisiologia , Bortezomib , Modelos Animais de Doenças , Feminino , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas da Mielina/genética , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/patologia , Bainha de Mielina/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Nervos Periféricos/efeitos dos fármacos , Nervos Periféricos/patologia , Nervos Periféricos/fisiologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/patologia , Inibidores de Proteases/toxicidade , Desdobramento de Proteína/efeitos dos fármacos , Células de Schwann/efeitos dos fármacos , Células de Schwann/patologia , Estresse Fisiológico/efeitos dos fármacos
8.
Neurosci Lett ; 485(1): 37-42, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-20800647

RESUMO

Neurotrophic cytokines, such as ciliary neurotrophic factor (CNTF) play an important role in the development and regeneration of the nervous system. In the present study, we screened gene expression induced by CNTF in adult dorsal root ganglion (DRG) neurons using the Illumina microarray. We found that the expression of both short and long forms of collapsin response-mediator protein 4 (CRMP4) was increased in cultured primary sensory neurons by CNTF. In addition, sciatic nerve injury induced the expression of CRMP4 mRNA and protein in DRG neurons. Finally, the increased CRMP4 protein was transported into peripheral axons following nerve injury. These findings indicate that CRMP4 may be a target gene for CNTF in the regenerative axon growth of DRG neurons after injury.


Assuntos
Fator Neurotrófico Ciliar/fisiologia , Gânglios Espinais/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Células Receptoras Sensoriais/metabolismo , Animais , Axônios/metabolismo , Células Cultivadas , Fator Neurotrófico Ciliar/farmacologia , Gânglios Espinais/citologia , Perfilação da Expressão Gênica , Proteínas do Tecido Nervoso/genética , Análise de Sequência com Séries de Oligonucleotídeos , Transporte Proteico , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo
9.
Korean J Physiol Pharmacol ; 14(2): 77-81, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20473378

RESUMO

Plasma cholesterol is increased in normal aging in both rodents and humans. This is associated with reduced elimination of cholesterol and decreased receptor-mediated clearance of plasma low-density lipoprotein (LDL) cholesterol. The aims of this study were: (1) to determine age-related changes in plasma lipid profiles, and (2) to determine the effect of fenofibrate, an activator of peroxisome proliferator activated receptor alpha (PPAR alpha), on plasma lipid profiles in normal rats on a standard diet. Male Sprague-Dawley (SD) rats (n=15) were fed standard chow and water from 10 to 25 weeks of age. During that period, we measured daily food intake, body weight, fasting and random blood glucose levels, plasma total cholesterol (TC), triglycerides (TG), and free fatty acid (FFA) levels. At 20 weeks of age, all rats were randomly divided into two groups: a fenofibrate group (in which rats were gavaged with 300 mg/kg/day of fenofibrate) and a control group (gavaged with water). Fenofibrate treatment lasted 5 weeks. There were no significant changes in daily food intake, blood glucose, and plasma TG level with age. Body weight, plasma TC, and FFA levels were significantly increased with age. Fenofibrate significantly decreased plasma concentrations of TC and FFA, which had been increased with age. However, fenofibrate did not influence the plasma concentration of TG, which had not increased with age. These results suggest that fenofibrate might have a novel role in preventing age-related hypercholesterolemia in SD rats on a normal diet.

10.
Mycobiology ; 38(1): 46-51, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23956624

RESUMO

The aim of this study was to determine the in vitro anti-inflammatory effect of hot water extract from Cordyceps militaris fruiting bodies (CMWE) on lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release in RAW 264.7 cells. The treatment of macrophages with various concentrations of hot CMWE significantly reduced LPS-induced production as well as NO, TNF-α and IL-6 secretion in a concentration-dependent manner. These results suggest that CMWE have potent inhibitory effects on the production of these inflammatory mediators.

11.
Toxicol Res ; 26(1): 37-46, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24278504

RESUMO

This study aimed to elucidate anti-inflammatory activities from extracts of Asterina pectinifera on nitric oxide (NO) production, TNF-α and IL-6 release in lipopolysaccharide (LPS) -stimulated murine macrophage cell, RAW264.7. We prepared the methanolic extracts (60-MAP, 70-MAP, 80-MAP and 90-MAP) , aqueous extract (W-AP) and functional bioactive compound fraction (He-AP and EA-AP) from Asterina pectinifera according to extract method. The 60-MAP, 70-MAP, 80-MAP, 90-MAP and W-AP were significantly suppressed LPS-induced production NO, TNF-α and IL-6 secretion in a concentration-dependent manner (P < 0.05) . Especially, 80-MAP by extracted 80% methanol had the strongest activity in reduction of inflammatory mediators among these extracts. Indeed, to identify active fraction, which contained potential bioactive compounds, from 80-MAP of Asterina pectinifera, we tested anti-inflammatory activity of the He-AP or the EA-AP. The He-AP was next extracted from 80-MAP and the EA-AP were extracted from the other methanol layer except the He-AP. The EA-AP demonstrated a strong anti-inflammatory effect through its ability to reduce NO production and it also inhibited the production of proinflammatory cytokines such as IL-6 and TNF-α at low concentration. These results suggested that the methanolic extract from Asterina pectinifera had the potential inhibitory effects on the production of these inflammatory mediators.

12.
Korean J Physiol Pharmacol ; 13(2): 131-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19885008

RESUMO

The binding of interleukin-6 (IL-6) cytokine family ligands to the gp130 receptor complex activates the Janus kinase (JAK)/ signal transducer and activator of transcription 3 (STAT3) signal transduction pathway, where STAT3 plays an important role in cell survival and tumorigenesis. Constitutive activation of STAT3 has been frequently observed in many cancer tissues, and thus, blocking of the gp130 signaling pathway, at the JAK level, might be a useful therapeutic approach for the suppression of STAT3 activity, as anticancer therapy. AG490 is a tyrphostin tyrosine kinase inhibitor that has been extensively used for inhibiting JAK2 in vitro and in vivo. In this study, we demonstrate a novel mechanism associated with AG490 that inhibits the JAK/STAT3 pathway. AG490 induced downregulation of gp130, a common receptor for the IL-6 cytokine family compounds, but not JAK2 or STAT3, within three hours of exposure. The downregulation of gp130 was not caused by enhanced degradation of gp130 or by inhibition of mRNA transcription. It most likely occurred by translation inhibition of gp130 in association with phosphorylation of the eukaryotic initiation factor-2alpha . The inhibition of protein synthesis of gp130 by AG490 led to immediate loss of mature gp130 in cell membranes, due to its short half-life, thereby resulting in reduction in the STAT3 response to IL-6. Taken together, these results suggest that AG490 blocks the STAT3 activation pathway via a novel pathway.

13.
Korean J Physiol Pharmacol ; 13(3): 161-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19885032

RESUMO

In the peripheral nerves, injury-induced cytokines and growth factors perform critical functions in the activation of both the MEK/ERK and JAK/STAT3 pathways. In this study, we determined that nerve injury-induced ERK activation was temporally correlated with STAT3 phosphorylation at the serine 727 residue. In cultured Schwann cells, we noted that ERK activation is required for the serine phosphorylation of STAT3 by neuropoietic cytokine interleukin-6 (IL-6). Serine phosphorylated STAT3 by IL-6 was transported into Schwann cell nuclei, thereby indicating that ERK may regulate the transcriptional activity of STAT3 via the induction of serine phosphorylation of STAT3. Neuregulin-1 (NRG) also induced the serine phosphorylation of STAT3 in an ERK-dependent fashion. In contrast with the IL-6 response, serine phosphorylated STAT3 induced by NRG was not detected in the nucleus, thus indicating the non-nuclear function of serine phosphorylated STAT3 in response to NRG. Finally, we determined that the inhibition of ERK prevented injury-induced serine phosphorylation of STAT3 in an ex-vivo explants culture of the sciatic nerves. Collectively, the results of this study show that ERK may be an upstream kinase for the serine phosphorylation of STAT3 induced by multiple stimuli in Schwann cells after peripheral nerve injury.

14.
Glia ; 57(16): 1825-34, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19455715

RESUMO

The ubiquitin-proteasome system (UPS), lysosomes, and autophagy are essential protein degradation systems for the regulation of a variety of cellular physiological events including the cellular response to injury. It has recently been reported that the UPS and autophagy mediate the axonal degeneration caused by traumatic insults and the retrieval of nerve growth factors. In the peripheral nerves, axonal degeneration after injury is accompanied by myelin degradation, which is tightly related to the reactive changes of Schwann cells called dedifferentiation. In this study, we examined the role of the UPS, lysosomal proteases, and autophagy in the early phase of Wallerian degeneration of injured peripheral nerves. We found that nerve injury induced an increase in the ubiquitin conjugation and lysosomal-associated membrane protein-1 expression within 1 day without any biochemical evidence for autophagy activation. Using an ex vivo explant culture of the sciatic nerve, we observed that inhibiting proteasomes or lysosomal serine proteases prevented myelin degradation, whereas this was not observed when inhibiting autophagy. Interestingly, proteasome inhibition, but not leupeptin, prevented Schwann cells from inducing dedifferentiation markers such as p75 nerve growth factor receptor and glial fibrillary acidic protein in vitro and in vivo. In addition, proteasome inhibitors induced cell cycle arrest and cellular process formation in cultured Schwann cells. Taken together, these findings indicate that the UPS plays a role in the phenotype changes of Schwann cells in response to nerve injury.


Assuntos
Desdiferenciação Celular/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/metabolismo , Ubiquitinação/efeitos dos fármacos , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Axotomia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Imunofluorescência , Processamento de Imagem Assistida por Computador , Leupeptinas/farmacologia , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Mielinizadas/metabolismo , Células de Schwann/citologia , Células de Schwann/efeitos dos fármacos , Nervo Isquiático/citologia , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/lesões , Ubiquitinação/fisiologia , Degeneração Walleriana/metabolismo
15.
Biochem Biophys Res Commun ; 362(4): 1057-62, 2007 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-17825258

RESUMO

Netrin and its receptors, DCC (Deleted in Colorectal Cancer) and Unc5, are proposed to be involved in the axon guidance and neuroglial migration during development. However, accumulating evidence implies that they may also participate in the cell survival and apoptosis. Here, we show that netrin-1 induces proliferation of Schwann cells. Unc5b is the sole receptor expressed in RT4 schwannoma cells and adult primary Schwann cells, and netrin-1 and Unc5b are found to be expressed in the injured sciatic nerve. It was also found that the netrin-1-induced Schwann cell proliferation was blocked by the specific inhibition of Unc5b expression with RNAi. These data suggest that netrin-1 could be an endogenous trophic factor for Schwann cells in the injured peripheral nerves.


Assuntos
Fatores de Crescimento Neural/administração & dosagem , Receptores de Superfície Celular/metabolismo , Células de Schwann/metabolismo , Neuropatia Ciática/metabolismo , Proteínas Supressoras de Tumor/administração & dosagem , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Netrina-1 , Ratos , Ratos Sprague-Dawley , Células de Schwann/efeitos dos fármacos , Células de Schwann/patologia , Neuropatia Ciática/patologia
16.
J Korean Med Sci ; 22(2): 242-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17449931

RESUMO

Mesenchymal stem cells (MSC) are multipotent in nature and believed to facilitate the engraftment of hematopoietic stem cells (HSC) when transplanted simultaneously in animal studies and even in human trials. In this study, we transfected culture-expanded MSC with granulocyte macrophage-colony stimulating factor (GMCSF) and stem cell factor (SCF) cytokine genes and then cotransplanted with mononuclear cells (MNC) to further promote HSC engraftment. MNC were harvested from cord blood and seeded in long-term culture for ex vivo MSC expansion. A total of 1 x 10(7) MNC plus MSC/microL were introduced to the tail vein of nonobese diabetic/severe combined immunodeficiency mice. After 6-8 weeks later, homing and engraftment of human cells were determined by flow cytometry and fluorescence in situ hybridization studies. The total nucleated cell count and the engraftment of CD45+/CD34+ cells and XX or XY positive human cells were significantly increased in cotransplanted mice and even higher with the cytokine gene-transfected MSC (GM-CSF>SCF, p<0.05) than in transplantation of MNC alone. These results suggest that MSC transfected with hematopoietic growth factor genes are capable of enhancing the hematopoietic engraftment. Delivering genes involved in homing and cell adhesions, CXCR4 or VLA, would further increase the efficiency of stem cell transplantation in the future.


Assuntos
Sobrevivência de Enxerto/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Fator de Células-Tronco/metabolismo , Transfecção/métodos , Animais , Melhoramento Genético/métodos , Camundongos , Camundongos SCID , Proteínas Recombinantes , Fator de Células-Tronco/genética
17.
Oncol Rep ; 17(4): 919-23, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17342337

RESUMO

HS-1200, a synthetic chenodeoxycholic acid derivative, has cytotoxic activity in various human cancer cells. The present study was undertaken to examine whether HS-1200 sensitizes radiation-induced apoptosis in MCF-7 human breast carcinoma cells. Clonogenic assay elucidated that the combination treatment with HS-1200 and radiation induced more cytotoxic effects than the radiation treatment alone. Nuclear staining, DNA electrophoresis and Western blot analysis for poly(ADP-ribose) polymerase revealed that the increased cytotoxic effect by the combination treatment resulted from the augmentation of apoptosis. There was an increase in the expression level of Bax and its translocation onto the mitochondria, a reduction in the mitochondrial membrane potential in the earlier time-points, and the release of cytochrome c into the cytosol increased in the MCF-7 cells treated with radiation and HS-1200 compared to the cells treated only with radiation. Therefore, the synthetic bile acid derivative, HS-1200, could have the therapeutic potential as a radiosensitizer in MCF-7 cells.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/radioterapia , Ácido Quenodesoxicólico/análogos & derivados , Radiossensibilizantes/farmacologia , Proteínas Reguladoras de Apoptose/análise , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Ácido Quenodesoxicólico/farmacologia , Ácido Quenodesoxicólico/uso terapêutico , Terapia Combinada , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Poli Adenosina Difosfato Ribose/análise , Radiossensibilizantes/uso terapêutico , Células Tumorais Cultivadas
18.
J Korean Med Sci ; 20(6): 1046-52, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16361820

RESUMO

Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL) has been reported to specifically kill malignant cells but to be relatively nontoxic to normal cells. One of disadvantages to previous in vivo protocols was the need for large quantities of TRAIL recombinant protein to suppress tumor growth. To evaluate the antitumor activity and therapeutic value of the TRAIL gene, we constructed adenoviral vectors expressing the human TRAIL gene (Ad.hTRAIL) and transferred them into malignant glioma cells in vitro and tumors in vivo, as an alternative to recombinant soluble TRAIL protein. The results show that TRAIL-sensitive glioma cells infected Ad.hTRAIL undergo apoptosis through the production and expression of TRAIL protein. The in vitro transfer elicited apoptosis, as demonstrated by the quantification of viable or apoptotic cells and by the analysis of cleavage of poly (ADP-ribose) polymerase. Furthermore, in vivo administration of Ad.hTRAIL at the site of tumor implantation suppressed the outgrowth of human glioma xenografts in SCID mice. These results further define Ad.hTRAIL as an anti-tumor therapeutic and demonstrate its potential use as an alternative approach to treatment for malignant glioma.


Assuntos
Adenoviridae/genética , Proteínas Reguladoras de Apoptose/genética , Terapia Genética/métodos , Glioma/terapia , Glicoproteínas de Membrana/genética , Fator de Necrose Tumoral alfa/genética , Animais , Apoptose , Linhagem Celular Tumoral , Expressão Gênica , Glioma/patologia , Humanos , Camundongos , Camundongos SCID , Transplante de Neoplasias , Ligante Indutor de Apoptose Relacionado a TNF , Transplante Heterólogo
19.
Biochem Biophys Res Commun ; 329(1): 25-31, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15721268

RESUMO

Human mesenchymal stem cells (hMSC), that have been reported to be present in bone marrow, adipose tissues, dermis, muscles, and peripheral blood, have the potential to differentiate along different lineages including those forming bone, cartilage, fat, muscle, and neuron. Therefore, hMSC are attractive candidates for cell and gene therapy. The optimal conditions for hMSC expansion require medium supplemented with fetal bovine serum (FBS). Some forms of cell therapy will involve multiple doses, raising a concern over immunological reactions caused by medium-derived FBS proteins. In this study, we cultured human adipose stromal cells (hADSC) and bone marrow stroma cells (HBMSC) in human serum (HS) during their isolation and expansion, and demonstrated that they maintain their proliferative capacity and ability for multilineage differentiation and promote engraftment of peripheral blood-derived CD34(+) cells mobilized from bone marrow in NOD/SCID mice. Our results indicate that hADSC and hBMSC cultured in HS can be used for clinical trials of cell and gene therapies, including promotion of engraftment after allogeneic HSC transplantation.


Assuntos
Tecido Adiposo/citologia , Células-Tronco Hematopoéticas/citologia , Células Estromais/citologia , Tecido Adiposo/metabolismo , Animais , Antígenos CD34/biossíntese , Células da Medula Óssea/citologia , Diferenciação Celular , Proliferação de Células , Transplante de Células , Terapia Genética , Humanos , Antígenos Comuns de Leucócito/biossíntese , Leucócitos Mononucleares/citologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Osteoblastos/metabolismo , Fatores de Tempo
20.
J Korean Med Sci ; 19(5): 635-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15483335

RESUMO

We assessed the cytokine combinations that are best for ex vivo expansion of cord blood (CB) and the increment for cell numbers of nucleated cells, as well as stem cells expressing homing receptors, by an ex vivo expansion of cryopreserved and unselected CB. Frozen leukocyte concentrates (LC) from CB were thawed and cultured at a concentration of 1 x 10(5)/mL in media supplemented with a combination of SCF (20 ng/mL)+TPO (50 ng/mL)+FL (50 ng/mL)+/-IL-6 (20 ng/mL)+/-G-CSF (20 ng/mL). After culturing for 14 days, the expansion folds of cell numbers were as follows: TNC 22.3+/-7.8 approximately 26.3+/-4.9, CFU-GM 4.7+/-5.1 approximately 11.7+/-2.6, CD34+CD38- cell 214.0+/-251.9 approximately 464.1+/-566.1, CD34+CXCR4+ cell 4384.5+/-1664.7 approximately 7087.2+/-4669.3, CD34+VLA4+ cell 1444.3+/-1264.0 approximately 2074.9+/-1537.0, CD34+VLA5+ cell 86.2+/-50.9 approximately 113.2+/-57.1. These results revealed that the number of stem cells expressing homing receptors could be increased by an ex vivo expansion of cryopreserved and unselected CB using 3 cytokines (SCF, TPO, FL) only. Further in vivo studies regarding the engraftment after expansion of the nucleated cells, as well as the stem cells expressing homing receptors will be required.


Assuntos
Sangue Fetal/citologia , Receptores de Retorno de Linfócitos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , ADP-Ribosil Ciclase/metabolismo , ADP-Ribosil Ciclase 1 , Antígenos CD/metabolismo , Antígenos CD34/metabolismo , Criopreservação , Humanos , Integrina alfa4beta1/metabolismo , Integrina alfa5beta1/metabolismo , Glicoproteínas de Membrana , Proteínas de Membrana , Receptores CXCR4/metabolismo , Fator de Células-Tronco , Trombopoetina
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