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1.
Cell Death Dis ; 5: e1190, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24763047

RESUMO

Oplopantriol-A (OPT) is a natural polyyne from Oplopanax horridus. We show here that OPT preferentially kills cancer cells and inhibits tumor growth. We demonstrate that OPT-induced cancer cell death is mediated by excessive endoplasmic reticulum (ER) stress. Decreasing the level of ER stress either by inactivating components of the unfolded protein response (UPR) pathway or by expression of ER chaperone protein glucose-regulated protein 78 (GRP78) decreases OPT-induced cell death. We show that OPT induces the accumulation of ubiquitinated proteins and the stabilization of unstable proteins, suggesting that OPT functions, at least in part, through interfering with the ubiquitin/proteasome pathway. In support of this, inhibition of protein synthesis significantly decreased the accumulation of ubiquitinated proteins, which is correlated with significantly decreased OPT-induced ER stress and cell death. Finally, we show that OPT treatment significantly induced the expression of BH3-only proteins, Noxa and Bim. Knockdown of both Noxa and Bim significantly blocked OPT-induced cell death. Taken together, our results suggest that OPT is a potential new anticancer agent that induces cancer cell death through inducing ER stress and BH3 proteins Noxa and Bim.


Assuntos
Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Poli-Inos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Autofagia/efeitos dos fármacos , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Feminino , Técnicas de Silenciamento de Genes , Humanos , Camundongos Nus , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Ubiquitinadas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Andrology ; 2(1): 107-16, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24265248

RESUMO

Diabetic erectile dysfunction (ED) has multiple causative factors, such as endothelial and smooth muscle dysfunction and cavernous fibrosis. Wnt signalling is essential for normal embryonic development and for tissue homeostasis in adults. Aberrant activation of Wnt family members has been implicated in tissue fibrosis and in angiogenesis. In this study, we investigated the differential expression of Wnts in the penises of mice with streptozotocin-induced diabetic ED. We also examined the effect of transforming growth factor-ß1 (TGF-ß1) on the expression of Wnts in primary cultured fibroblasts isolated from human tunica albuginea. Among the mouse and human Wnts tested, 16 mouse Wnts and 14 human Wnts were detected in the corpus cavernosum tissue of normal mice and in fibroblasts derived from human tunica albuginea respectively. We observed up-regulation of Wnt10b (known to be involved in tissue fibrosis) and down-regulation of Wnt16 (known to be involved in vasculogenesis and hematopoiesis), both in the diabetic condition in vivo and with treatment of fibroblasts with TGF-ß1 in vitro. Wnt10b was mainly expressed in fibroblasts and Wnt16 was colocalized with smooth muscle cells in the corpus cavernosum tissue. Cavernous TGF-ß1 protein expression and the degree of cavernous fibrosis determined by the ratio of collagen to smooth muscle content were significantly higher in diabetic mice than in controls. Cavernous endothelial content was significantly decreased by the diabetic condition. Overexpression of Wnt16 with plasmid vector accelerated tube formation in primary cultured mouse cavernous endothelial cells. However, down-regulation of Wnt10b with small interfering RNA did not decrease the production of extracellular matrix protein in human fibroblasts. This is the first report demonstrating the differential expression of Wnts in diabetic mouse penis. Aberrant Wnt expression might contribute to the pathogenesis of ED.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Experimental/metabolismo , Disfunção Erétil/complicações , Proteínas Proto-Oncogênicas/biossíntese , Fator de Crescimento Transformador beta1/farmacologia , Proteínas Wnt/biossíntese , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Células Cultivadas , Células Endoteliais , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Fibrose , Humanos , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso/fisiopatologia , Ereção Peniana/fisiologia , Pênis/fisiopatologia , Proteínas Proto-Oncogênicas/genética , Interferência de RNA , RNA Interferente Pequeno , Estreptozocina , Fator de Crescimento Transformador beta1/biossíntese , Proteínas Wnt/genética
3.
Andrology ; 1(2): 216-22, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23316017

RESUMO

A prerequisite for the successful clinical application of gene therapy in erectile dysfunction (ED) is the availability of safe and efficient gene delivery systems. The aim of this study was to examine the effectiveness of guanidinylated bioreducible polymer (GBP) polyplexes for gene delivery systems, which take advantage of the biodegradability of reducible disulfide bonds and the cell-penetrating ability of guanidine groups. For in vitro transfection experiments, we used mouse cavernous endothelial cells and A7r5 rat vascular smooth muscle cells. For in vivo experiments, we used a mouse model of hypercholesterolaemic ED in which 2-month-old male C57BL/6 mice were fed a diet containing 4% cholesterol and 1% cholic acid for 3 months. Animals or cells were treated with pCMV-Luc, poly(ethyleneimine) (PEI)25k/pCMV-Luc polyplex (weight ratio: 1) and GBP/pCMV-Luc polyplexes (weight ratio: 20, 40, 60 and 80). Gene expression was evaluated by luciferase assay, and the gene expression area was evaluated by immunohistochemistry. GBP had greater transfection efficiency as the weight ratio increased. GBP had sevenfold higher gene delivery efficiency in A7r5 cells at a weight ratio of 80 than did PEI25k. Moreover, the gene expression was more profoundly induced by GBP/pCMV-Luc than by pCMV-Luc in both the corpus cavernosum tissue of hypercholesterolaemic mice and in mouse cavernous endothelial cells, although the expression levels induced by the GBP gene delivery system were lower than those induced by the PEI25k gene delivery system. GBP revealed no considerable cytotoxicity to A7r5 cells and mouse cavernous endothelial cells (relative cell viability: 95 and 88% respectively), whereas PEI25k resulted in high cytotoxicity. Interestingly, immunofluorescent double staining revealed that luciferase expression induced by the GBP polyplex mainly overlapped with cavernous endothelial cells, but rarely with smooth muscle cells. The GBP-based non-viral gene expression system may be useful for the development of gene therapy in vasculogenic ED.


Assuntos
Disfunção Erétil/terapia , Técnicas de Transferência de Genes , Terapia Genética , Guanidina , Polímeros , Animais , Linhagem Celular , Células Cultivadas , Colesterol na Dieta/administração & dosagem , Modelos Animais de Doenças , Células Endoteliais , Disfunção Erétil/induzido quimicamente , Disfunção Erétil/genética , Expressão Gênica , Hipercolesterolemia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular , Pênis/irrigação sanguínea , Ratos , Transfecção
4.
Cell Death Dis ; 3: e376, 2012 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-22914324

RESUMO

Falcarindiol (FAD) is a natural polyyne with various beneficial biological activities. We show here that FAD preferentially kills colon cancer cells but not normal colon epithelial cells. Furthermore, FAD inhibits tumor growth in a xenograft tumor model and exhibits strong synergistic killing of cancer cells with 5-fluorouracil, an approved cancer chemotherapeutic drug. We demonstrate that FAD-induced cell death is mediated by induction of endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR). Decreasing the level of ER stress, either by overexpressing the ER chaperone protein glucose-regulated protein 78 (GRP78) or by knockout of components of the UPR pathway, reduces FAD-induced apoptosis. In contrast, increasing the level of ER stress by knocking down GRP78 potentiates FAD-induced apoptosis. Finally, FAD-induced ER stress and apoptosis is correlated with the accumulation of ubiquitinated proteins, suggesting that FAD functions at least in part by interfering with proteasome function, leading to the accumulation of unfolded protein and induction of ER stress. Consistent with this, inhibition of protein synthesis by cycloheximide significantly decreases the accumulation of ubiquitinated proteins and blocks FAD-induced ER stress and cell death. Taken together, our study shows that FAD is a potential new anticancer agent that exerts its activity through inducing ER stress and apoptosis.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Di-Inos/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Álcoois Graxos/toxicidade , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Di-Inos/uso terapêutico , Sinergismo Farmacológico , Chaperona BiP do Retículo Endoplasmático , Álcoois Graxos/uso terapêutico , Fluoruracila/toxicidade , Células HCT116 , Proteínas de Choque Térmico/antagonistas & inibidores , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Camundongos , Transplante Heterólogo , Ubiquitinação/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos
5.
Appl Microbiol Biotechnol ; 55(6): 686-92, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11525615

RESUMO

Candida glycerinogenes, an osmotolerant yeast isolated from a natural sample in an environment of high osmotic pressure, had a modest sugar-tolerance and an extremely high glycerol productivity. The optimum conditions for glycerol formation by C. glycerinogenes were a temperature of 29-33 degrees C and a pH of 4-6. The optimum medium for glycerol production consisted of 230-250 g glucose/l, 2 g urea/l and 5 ml corn steep liquor/l (55-65 mg phosphates/l); the pH was not adjusted. The highest yield of glycerol was 64.5% (w/w) based on consumed glucose from 240 g glucose/l, and the highest concentration of glycerol was 137 g/l from 260 g glucose/l. These results were obtained by using a 30-l agitated fermentor under optimal fermentation conditions. In ten batch-fermentations carried out in a 50,000-l airlift fermentor, an average yield of glycerol of 50.67% (w/w) and an average glycerol concentration of 121.9 g/l were obtained from an average 240.6 g glucose/l.


Assuntos
Candida/metabolismo , Glicerol/metabolismo , Aerobiose , Reatores Biológicos , Meios de Cultura , Fermentação , Glucose/metabolismo , Glucose/farmacologia , Concentração de Íons de Hidrogênio , Concentração Osmolar , Fosfatos/metabolismo , Fosfatos/farmacologia , Temperatura , Ureia/metabolismo , Ureia/farmacologia
6.
Sheng Wu Gong Cheng Xue Bao ; 16(2): 203-6, 2000 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-10976327

RESUMO

The relationship between oxygen supply and production of glycerol or byproduct with Candida glycerolgenesis have been studied. The experiments in shake flasks indicated that the biomass was determined by the concentration of corn steep liquor when other fermentation condition was constant, the concentration of corn steep liquor and the ratio of the volume of the medium to the capacity of the flask affected the yield of glycerol and other byproducts because of different oxygen supply. With 0.4% corn steep liquid and the ratio of the volume of the medium to the capacity of the flask was 0.08, the yeast yielded higher level of glycerol concentration and little other byproducts, while oxygen was insufficient for glycerol production such as the ratio was 0.24, the yeast would produce much more alcohol and other byproduct, then decreased the yield of glycerol. In the fermentation process of 5 L fermentor, agitator speed mostly affected the DO level in the medium. In growth phase the specific oxygen consumption rate of C. glycerolgenesis was 28 mg/(g.h), and during fermentation process it was 16 mg/(g.h). With suitable oxygen supply, C. glycerolgenesis can produce high level of glycerol whereas ethanol and other byproducts was nearly zero.


Assuntos
Candida/metabolismo , Glicerol/metabolismo , Oxigênio/farmacologia , Fermentação
7.
J Oral Maxillofac Surg ; 58(8): 847-51, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10935582

RESUMO

PURPOSE: This article describes the endonasal endoscopic reduction (EER) of blowout fractures (BOFs) of the medial orbital walls and reports the clinical results. PATIENTS AND METHODS: Sixteen patients who underwent EER for a BOF of the medial orbital wall were analyzed. The surgical indications for treatment were diplopia, limitation of eye movements, and significant enophthalmos. They were followed-up for at least 3 months after the surgery. Surgical techniques, surgical results, and postoperative complications were reviewed. RESULTS: There were no significant intraoperative or postoperative complications. Fourteen patients showed complete resolution of symptoms after the surgery. One patient, who had persistent diplopia and remaining enophthalmos, underwent medial wall reconstruction with a Medpor surgical implant (Porex Surgical Inc, College Park, GA) by a transorbital approach. Another patient, who had residual enophthalmos, had correction of enophthalmos after insertion of a Medpor implant. Both patients are now symptom-free. CONCLUSION: The results indicate that EER is a safe and effective technique for the treatment of BOFs of the medial orbital wall.


Assuntos
Endoscopia/métodos , Nariz/cirurgia , Fraturas Orbitárias/cirurgia , Adolescente , Adulto , Diplopia/etiologia , Enoftalmia/etiologia , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Motilidade Ocular/etiologia , Fraturas Orbitárias/complicações , Avaliação de Processos e Resultados em Cuidados de Saúde , Estudos Retrospectivos
8.
J Oral Maxillofac Surg ; 58(6): 617-20; discussion 620-1, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10847282

RESUMO

PURPOSE: This study investigated the relationship between the extent of fracture and enophthalmos in blowout fractures of the medial orbital wall. PATIENTS AND METHODS: Nine patients with isolated blowout fractures of the medial orbital wall, confirmed by computed tomography scans, were evaluated. The area of fracture and the volume of herniated orbital tissue were determined from computed tomography scans using simple linear measurements. Each of the calculated values for area and volume were compared with the degree of enophthalmos to determine whether there was any significant relationship between them. RESULTS: Enophthalmos increased proportionally as the area of fracture or the volume of herniated orbital tissue increased (P < .05). The area of fracture and the volume of herniated orbital tissue associated with 2 mm of enophthalmos were 1.9 cm2 and 0.9 mL, respectively, as calculated from the regression curve. CONCLUSION: Enophthalmos of 2 mm or more, which is a frequent indication for surgery, can be expected when the area of fracture is 1.9 cm2 or more, or the volume of herniated orbital tissue is 0.9 mL or more.


Assuntos
Enoftalmia/etiologia , Enoftalmia/patologia , Fraturas Orbitárias/complicações , Fraturas Orbitárias/patologia , Adulto , Feminino , Humanos , Modelos Lineares , Masculino , Fatores de Risco , Índices de Gravidade do Trauma
9.
Auris Nasus Larynx ; 26(4): 441-5, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10530740

RESUMO

A lacrimal sac mucocele is an uncommon disease usually treated by ophthalmologists. In rare cases, it is sometimes associated with a nasolacrimal duct cyst presenting as an intranasal cystic mass, which needs the involvement of an otolaryngologist in diagnosis and management. Two cases of lacrimal sac mucoceles with nasolacrimal duct cysts are presented with a brief literature review. Both cases presented with intranasal cystic masses that caused nasal obstruction and were cured with endoscopic marsupialization of the cysts.


Assuntos
Endoscopia/métodos , Mucocele/complicações , Mucocele/patologia , Ducto Nasolacrimal/patologia , Adulto , Criança , Feminino , Humanos , Masculino , Seios Paranasais/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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