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Following the publication of the above article, an interested reader drew to the authors' attention that Figs. 1C and 2 in the paper appeared to contain instances of duplicated data. The authors were able to consult their original data files, and realized that these figures had indeed been assembled incorrectly. Moreover, they identified further errors with a number of the other figures in their published formats (specifically, Figs. 3, 4, 6 and 7), and requested that a corrigendum be published to take account of all the errors that were made during the compilation of these figures. The Editor of International Journal of Molecular Medicine has considered the authors' request to publish a corrigendum, but has declined this request on account of the large number of errors that have been identified, and subsequently determined that this article should be retracted from the Journal on the basis of an overall lack of confidence in the presented data. Upon receiving this decision from the Editor, the authors were in agreement that the article should be retracted. The Editor apologizes to the readership of the Journal for any inconvenience caused. [International Journal of Molecular Medicine 39: 527538, 2017; DOI: 10.3892/ijmm.2017.2880].
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High fructose is considered a causative factor for oxidative stress and autophagy imbalance that cause kidney pathogenesis. Antioxidant polydatin isolated from Polygonum cuspidatum has been reported to protect against kidney injury. In this study, polydatin was found to ameliorate fructose-induced podocyte injury. It activated mammalian target of rapamycin complex 1 (mTORC1) and suppressed autophagy in glomeruli of fructose-fed rats and in fructose-exposed conditionally immortalized human podocytes (HPCs). Polydatin also enhanced nuclear factor-E2-related factor 2 (Nrf2)-dependent antioxidant capacity to suppress fructose-induced autophagy activation in vivo and in vitro, with the attenuation of fructose-induced up-regulation of cellular light chain 3 (LC3) II/I protein levels. This effect was abolished by Raptor siRNA in fructose-exposed HPCs. These results demonstrated that polydatin ameliorated fructose-induced autophagy imbalance in an mTORC1-dependent manner via improving Nrf2-dependent antioxidant capacity during podocyte injury. In conclusion, polydatin with anti-oxidation activity suppressed autophagy to protect against fructose-induced podocyte injury.
Assuntos
Antioxidantes/metabolismo , Autofagia , Comportamento Alimentar , Glucosídeos/farmacologia , Homeostase , Fator 2 Relacionado a NF-E2/metabolismo , Podócitos/metabolismo , Estilbenos/farmacologia , Trifosfato de Adenosina/biossíntese , Adenilato Quinase/metabolismo , Animais , Autofagia/efeitos dos fármacos , Frutose , Homeostase/efeitos dos fármacos , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Podócitos/efeitos dos fármacos , Podócitos/patologia , Proteinúria/complicações , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
BACKGROUND AND PURPOSE: Excessive fructose consumption is a risk factor for liver fibrosis. Pterostilbene protects against liver fibrosis. Here, we investigated the potential role and the mechanisms underlying the hepatocyte epithelial-mesenchymal transition (EMT) in fructose-induced liver fibrosis and protection by pterostilbene. EXPERIMENTAL APPROACH: Characteristic features of liver fibrosis in 10% fructose-fed rats and EMT in 5 mM fructose-exposed BRL-3A cells with or without pterostilbene and the change of miR-34a/Sirt1/p53 and transforming growth factor-ß1 (TGF-ß1)/Smads signalling were examined. MiR-34a inhibitor, miR-34a minic, or p53 siRNA were used to explore the role of miR-34a/Sirt1/p53 signalling in fructose-induced EMT and the action of pterostilbene. KEY RESULTS: Pterostilbene prevented fructose-induced liver injury with fibrosis in rats. Fructose caused hepatocyte undergoing EMT, gaining fibroblast-specific protein 1 and vimentin, and losing E-cadherin, effects attenuated by pterostilbene. Moreover, fructose induced miR-34a overexpression in hepatocytes with down-regulated Sirt1, increased p53 and ac-p53, and activated TGF-ß1/Smads signalling, whereas these disturbances were suppressed by miR-34a inhibitor. Additionally, miR-34a inhibitor and p53 siRNA prevented TGF-ß1-driven hepatocyte EMT under fructose exposure. Pterostilbene down-regulated miR-34a, up-regulated Sirt1, and suppressed p53 activation and TGF-ß1/Smads signalling in fructose-stimulated animals and cells but showed no additional effects with miR-34a inhibitor on miR-34a/Sirt1/p53 signalling in fructose-exposed hepatocytes. CONCLUSIONS AND IMPLICATIONS: These results strongly suggest that activation of miR-34a/Sirt1/p53 signalling is required for fructose-induced hepatocyte EMT mediated by TGF-ß1/Smads signalling, contributing to liver fibrosis in rats. Pterostilbene exhibits a protective effect against liver fibrosis at least partly through inhibiting miR-34a/Sirt1/p53 signalling activation.
Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Cirrose Hepática/metabolismo , Substâncias Protetoras/farmacologia , Estilbenos/farmacologia , Animais , Frutose , Hepatócitos/fisiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/patologia , Masculino , MicroRNAs/genética , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/genética , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína Supressora de Tumor p53/genéticaRESUMO
High dietary fructose is a key causative factor in the development of renal fibrosis. Pterostilbene has anti-fibrotic effect. Understanding the action mechanism of pterostilbene in fructose-induced renal fibrosis remains as a challenge. Here, fructose feeding was found to promote the progress of epithelial-to-mesenchymal transition (EMT) of proximal tubule epithelial cells (PTECs) and collagen deposition in renal cortex of rats with tubulointerstitial fibrosis. Simultaneously, it impaired insulin receptor (IR)/insulin receptor substrate-1 (IRS-1)/protein kinase B (Akt) pathway, and increased transforming growth factor-beta 1 (TGF-ß1) and TGF-ß type I receptor to enhance phosphorylation of drosophila mothers against decapentaplegic homolog 2 (Smad2) and Smad3, and Smad4 expression in rat kidney cortex. These changes were also observed in cultured PTECs HK-2 cells exposed to 5â¯mM fructose. The data from fructose-exposed HK-2 cells co-incubated with TGF-ß type I receptor inhibitor further demonstrated that the activation of TGF-ß1/TGF-ß type I receptor/Smads signaling promoted renal tubular EMT and collagen accumulation. Pterostilbene was found to ameliorate fructose-induced renal fibrosis in rats. Importantly, pterostilbene improved IR/IRS-1/Akt pathway impairment and suppressed TGF-ß1/TGF-ß type I receptor/Smads signaling activation in vivo and in vitro, being consistent with its reduction of EMT and collagen deposition. Upregulation of IR/Akt signaling by pterostilbene was also confirmed in Akt inhibitor (MK-2206 2HCl) or IR inhibitor (GSK1904529A)-treated HK-2 cells. Taken together, pterostilbene may be a promising therapeutic agent for the treatment of fructose-induced kidney fibrosis with insulin signaling impairment.
Assuntos
Células Epiteliais/patologia , Frutose/efeitos adversos , Túbulos Renais Proximais/patologia , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Proteínas Smad/metabolismo , Estilbenos/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Linhagem Celular , Colágeno/metabolismo , Citoproteção/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose , Insulina/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
Evodiamine (EVO) and Berberine (BBR), from Euodiae Fructus and Coptidis rhizoma, have been used as an herbal medicine pair in traditional Chinese medicine to exert synergistic antitumor effects against various types of tumor cells. However, their clinical use is limited by their poor solubility and adverse toxic side effects. Mesoporous silica nanoparticles (MSNs) possess excellent properties such as a readily functionalized surface, prominent biocompatibility, and huge specific surface area for loading with hydrophobic and hydrophilic drug. On this basis, a novel temperature- and pH-responsive dual drug delivery platform has been developed, in which lipid-coated MSN@p(NIPAM- co-MA) codelivers EVO and BBR. The results indicate that the nanocarrier improves the efficacy and biocompatibility of the drug pair and maintain desirable drug profiles at the low pH and higher temperature of the tumor microenvironment. The dual drug-loaded MSNs showed excellent synergistic therapy effects in vitro (cytotoxicity, cell migration and invasion, angiogenesis) and in vivo (growth of tumor grafts in mice). Meanwhile, the dual drug-loaded nanoparticles showed lower systemic toxicity than either drug alone, the free drug combination, or Taxol. These results suggest that the temperature- and pH-sensitive lipid-coated MSNs are a promising novel carrier for both hydrophobic and hydrophilic drugs.
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Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Dióxido de Silício/química , Animais , Berberina/administração & dosagem , Berberina/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Portadores de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Quinazolinas/administração & dosagem , Quinazolinas/uso terapêutico , Temperatura , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
AIM: To report the results of rhegmatogenous retinal detachment (RRD) repair after pars plana vitrectomy (PPV) without operative use of heavy liquid, and utilizing air tamponade in selected cases. METHODS: RRD patients without severity of proliferative vitreoretinopathy C2 or more underwent PPV without operative use of heavy liquid, and utilizing air tamponade were consecutively enrolled. Alternative postoperative facedown position or lateral position was required for 3-5d. RESULTS: Totally 36 eyes of 36 patients (24 males, 66.7%) aged 53.8±10.9y underwent this modified surgery. The mean number of retinal break was 2.1±1.3. Most of the eyes (29, 80.6%) had retinal detachment involving more than one quadrant. Twenty-two (61.1%) eyes with cataract had combined phacoemulsification and intraocular lens implantation. The mean follow up time was 4.6±1.8mo. Two eyes with retinal redetachment underwent a second retinal repair surgery with silicone oil tamponade, yielding the primary reattachment rate to 94.4% (34/36). Six (16.7%) eyes had intraocular pressure higher than 25 mm Hg. The visual acuity (logMAR) improved from 0.98±0.74 preoperatively to 0.52±0.31 postoperatively (P<0.001). CONCLUSION: The success rate of this modified retinal repair surgery is comparable with traditional surgery. This technique can be considered for certain retinal detachment patients, since its apparent advantages included lower surgical complications, reduced surgery expenditure, shorter time for postoperative facedown position, and avoiding silicone oil removal surgery.
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Oxidative stress is a critical factor in nonalcoholic fatty liver disease pathogenesis. MicroRNA-200a (miR-200a) is reported to target Kelch-like ECH-associated protein 1 (Keap1), which regulates nuclear factor erythroid 2-related factor 2 (Nrf2) anti-oxidant pathway. Polydatin (3,4',5-trihydroxy-stilbene-3-ß-D-glucoside), a polyphenol found in the rhizome of Polygonum cuspidatum, have anti-oxidative, anti-inflammatory and anti-hyperlipidemic effects. However, whether miR-200a controls Keap1/Nrf2 pathway in fructose-induced liver inflammation and lipid deposition and the blockade of polydatin are still not clear. Here, we detected miR-200a down-regulation, Keap1 up-regulation, Nrf2 antioxidant pathway inactivation, ROS-driven thioredoxin-interacting protein (TXNIP) over-expression, NOD-like receptor (NLR) family, pyrin domain containing 3 (NLRP3) inflammasome activation and dysregulation of peroxisome proliferator activated receptor-α (PPAR-α), carnitine palmitoyl transferase-1 (CPT-1), sterol regulatory element binging protein 1 (SREBP-1) and stearoyl-CoA desaturase-1 (SCD-1) in rat livers, BRL-3A and HepG2 cells under high fructose induction. Furthermore, the data from the treatment or transfection of miR-200a minic, Keap1 and TXNIP siRNA, Nrf2 activator and ROS inhibitor demonstrated that fructose-induced miR-200a low-expression increased Keap1 to block Nrf2 antioxidant pathway, and then enhanced ROS-driven TXNIP to activate NLRP3 inflammasome and disturb lipid metabolism-related proteins, causing inflammation and lipid deposition in BRL-3A cells. We also found that polydatin up-regulated miR-200a to inhibit Keap1 and activate Nrf2 antioxidant pathway, resulting in attenuation of these disturbances in these animal and cell models. These findings provide a novel pathological mechanism of fructose-induced redox status imbalance and suggest that the enhancement of miR-200a to control Keap1/Nrf2 pathway by polydatin is a therapeutic strategy for fructose-associated liver inflammation and lipid deposition.
Assuntos
Anti-Inflamatórios/uso terapêutico , Frutose/efeitos adversos , Glucosídeos/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Fígado/efeitos dos fármacos , MicroRNAs/imunologia , Estilbenos/uso terapêutico , Animais , Antioxidantes/uso terapêutico , Linhagem Celular , Medicamentos de Ervas Chinesas/uso terapêutico , Inflamação/imunologia , Inflamação/patologia , Proteína 1 Associada a ECH Semelhante a Kelch/imunologia , Lipídeos/análise , Lipídeos/imunologia , Fígado/imunologia , Fígado/patologia , Masculino , Fator 2 Relacionado a NF-E2/imunologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
Gastric cancer (GC) is the third leading cause of cancer death due to its poor prognosis and limited treatment options. Evidence indicates that pseudogene-derived long noncoding RNAs (lncRNAs) may be important players in human cancer progression, including GC. In this paper, we report that a newly discovered pseudogene-derived lncRNA named DUXAP8, a 2107-bp RNA, was remarkably upregulated in GC. Additionally, a higher level of DUXAP8 expression in GC was significantly associated with greater tumor size, advanced clinical stage, and lymphatic metastasis. Patients with a higher level of DUXAP8 expression had a relatively poor prognosis. Further experiments revealed that knockdown of DUXAP8 significantly inhibited cell proliferation and migration, as documented in the SGC7901 and BGC823 cell lines. Furthermore, RNA immunoprecipitation and chromatin immunoprecipitation assays demonstrated that DUXAP8 could epigenetically suppress the expression of PLEKHO1 by binding to EZH2 and SUZ12 (two key components of PRC2), thus promoting GC development. Taken together, our findings suggest that the pseudogene-derived lncRNA DUXAP8 promotes the progression of GC and is a potential therapeutic target for GC intervention.
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Osteoporosis (OP) increases the risk of bone fractures and other complications, and is thus a major clinical problem. In this study, we examined the effect of isopsoralen on the differentiation of bone-derived marrow mesenchymal stem cells (BMSCs) into osteoblasts and adipocytes, as well as bone formation under osteoporotic conditions. Primary femoral BMSCs isolated from C57BL/6 mice were used to evaluate the isopsoralen-mediated regulation of the expression of alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) during osteogenesis 2 weeks. We also examined the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding protein ß (C/EBPß) under adipogenic conditions for 1 and 2 weeks. In addition, ovariectomized (OVX) mice were used to examine the effects of isopsoralen on bone formation for 2 months. Finally, mammalian target of rapamycin complex 1 (mTORC1) signaling was examined under osteogenic and adipogenic conditions. We found that following treatment with isopsoralen, the expression levels of ALP, OCN and RUNX2 were upregulated, whereas those of PPARγ and C/EBPß were downregulated. mTORC1 signaling was also inhibited in vitro and in vivo. In the OVX mice that were intragastrically administered isopsoralen, bone parameters (trabecular thickness, bone volume/total volume and trabecular number) in the distal femoral metaphysis were significantly increased and the adipocyte number was decreased. On the whole, our findings demonstrate that isopsoralen promoted BMSC differentiation into osteoblasts and suppressed differentiation into adipocytes.
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Adipogenia/efeitos dos fármacos , Adiposidade , Medula Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Furocumarinas/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Biomarcadores , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteocalcina/metabolismo , PPAR gama/metabolismo , Microtomografia por Raio-XRESUMO
Osteoporosis is a systemic skeletal disease that is characterized by low bone density and microarchitectural deterioration of bone tissue. The increasing prevalence of osteoporosis has attracted much attention. In this study, MC3T3-E1 pre-osteoblasts were treated with the natural compound, baicalein (0.1 µmol/L, 1 µmol/L, 10 µmol/L), to stimulate differentiation over a 14-day period. In addition, a canonical ovariectomized (OVX) mouse model was used to investigate the effect of 3-month baicalein treatment (10 mg/kg per day) in preventing postmenopausal osteoporosis. In vitro, we found that baicalein induced activation of alkaline phosphatase, stimulated the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway, and induced expression of osteoblast differentiation markers, ie, osteocalcin, osterix, collagen Iα1, and runt-related transcription factor 2 (RUNX2), in osteoblasts. In vivo, several bone parameters, including trabecular thickness, trabecular bone mineral density, and trabecular number, in the distal femoral metaphysis were significantly increased in OVX mice treated intragastrically with baicalein for 3 months compared with OVX mice that were not treated with baicalein. We also found that expression of osteocalcin and RUNX2 was decreased in primary ossified tissue from the OVX group, and baicalein increased the levels of osteocalcin and RUNX2 in OVX mice. These data suggest that baicalein can stimulate MC3T3-E1 cells to differentiate into osteoblasts via activation of the mTORC1 signaling pathway, which includes protein kinases and transcription factors such as P-4E/BP1 and P-S6K1.
Assuntos
Flavanonas/farmacologia , Complexos Multiproteicos/metabolismo , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Relação Dose-Resposta a Droga , Feminino , Flavanonas/administração & dosagem , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , OvariectomiaRESUMO
Diabetes and cancer are both serious health problems worldwide and can lead to a significant burden on society with high incidence. Studies show that diabetes, which may be the reason of cancer metastasis, can increase cancer incidence and mortality. Bone is one of the most preferential metastatic target sites for cancers. Studies also indicate that OPG and RANKL which regulate bone reabsorption play significant roles in the process of bone tumor metastasis. In addition, metformin as a commonly used medicine for type 2 diabetes is a negative regulator of RANKL and inhibits the differentiation of osteoclasts. We present a hypothesis that metformin serves an inhibitory effect on bone metastasis of cancer via OPG/RANKL/RANK system.
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Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Metformina/farmacologia , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Neoplasias Ósseas/metabolismo , Complicações do Diabetes , Humanos , Modelos Biológicos , Osteoclastos/efeitos dos fármacosRESUMO
AIM: To investigate the effect of endogenous n-3 polyunsaturated fatty acids (PUFAs) on bone marrow adipogenesis under osteoporosis conditions. METHODS: A mouse osteoporosis model overexpressing the FAT1 gene from Caenorhabditis elegans and converting n-6 PUFAs to n-3 PUFAs endogenously was used. RESULTS: The mice presented significantly lower bone marrow adiposity (adipocyte volume/tissue volume, mean adipocyte number) but increased the bone parameters (bone mineral density, bone mineral content, bone volume/total volume) in the distal femoral metaphysis. CONCLUSION: Endogenous n-3 PUFAs protect bone marrow adipogenesis, which provides a novel drug target.
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Adipogenia , Medula Óssea/metabolismo , Caderinas/fisiologia , Ácidos Graxos Ômega-3/fisiologia , Osteoporose/prevenção & controle , Ovariectomia , Adiposidade , Animais , Caderinas/genética , Subunidade alfa 1 de Fator de Ligação ao Core/análise , Feminino , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , PPAR gama/análiseRESUMO
Osteoarthritis (OA) is a gradually progressive degenerative disease characterized by gradual inflammatory loss of articular cartilage caused by increased proteolytic catabolism, mediated by interleukin-1 (IL-1), tumor necrosis factor α (TNF-α), matrix metalloproteinase (MMPs), aggrecanases and other proteinases, and reduced anabolism of cartilage components, contributed by interleukin-4 (IL-4), interleukin-10 (IL-10), insulin-like growth factor 1 (IGF-1), transforming growth factor ß (TGF-ß), and bone morphogenetic proteins (BMPs). Substantial studies showed n-3 polyunsaturated fatty acids (n-3 PUFAs) exhibit a powerful anti-inflammatory effects in and ex vivo through reducing the production of IL-1 and TNF-α and increasing the expression of IL-4, IL-10, TGF-ß and IGF-1 in OA. Meanwhile, more convincing results are observed in the fat-1 transgenic mice, which are exogenously inserted in a fat-1 gene from Caenorhabditis elegans, which can endogenously convert n-6 polyunsaturated fatty acids (n-6 PUFAs) to n-3 PUFAs. Taken together, it has long been realized that dietary supplementation with fish oils that are plentiful of n-3 PUFAs can bring benefits in the treatment of osteoarthritis. Previously two phase I human studies based on in vitro transfer of the cDNA via lentivirus to arthritic joints have confirmed its feasibility and safety in human subjects. Consequently, we hypothesis that directly infect the chondrocytes and synoviocytes with lentivirus carrying the fat-1 gene could be a well therapeutic strategy for OA in humans.
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Caderinas/genética , Terapia Genética , Lentivirus/genética , Osteoartrite/prevenção & controle , Humanos , Osteoartrite/genéticaRESUMO
The present study combined chemical analyses and biological measurements to investigate biphasic effects of La on Cd stress in leaves of Vicia faba seedlings, which were hydroponically cultivated for 15 d in the combination of 6 µM CdCl(2) and 2 to 480 µM La(NO(3))(3), respectively. The results showed that contents of Cd first elevated above and then declined below the 6 µM single Cd treatment when 2 to 30 µM extraneous La were combined. Contents of mineral nutrients altered differentially and became imbalanced. No distinct band was observed in catalase (CAT), guaiacol peroxidase (GPX), or ascorbate peroxidase (APX) patterns, but in superoxide dismutase (SOD) isozymes by the supplementation with 8 to 480 µM of extraneous La. Superoxide dismutase and APX activities changed as a U-shaped curve; however, CAT and GPX changed as an inverted U-shaped curve along with increasing La. Moreover, heat shock protein 70 (HSP 70) production was reduced below the single treatment of Cd at 2 to 8 µM of extraneous La and enhanced thereafter. Thus, La at lower concentrations promoted antioxidation against Cd stress; La at higher concentrations turned to prooxidant effects, implicating potential ecological risk. Heat shock protein 70, combined with the antioxidant enzymes, constitutes an integrative defense system, which can be used to estimate the degree of antioxidation or prooxidation of extraneous La to Cd-induced oxidative stress in the seedlings.
Assuntos
Cádmio/toxicidade , Lantânio/toxicidade , Poluentes do Solo/toxicidade , Vicia faba/efeitos dos fármacos , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Ecologia , Proteínas de Choque Térmico HSP70/metabolismo , Oxirredução , Estresse Oxidativo , Peroxidase/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/fisiologia , Superóxido Dismutase/metabolismo , Vicia faba/metabolismo , Vicia faba/fisiologiaRESUMO
BACKGROUND & OBJECTIVE: Nasopharyngeal carcinoma (NPC) is one of the most common cancers in South China and Southeast Asia. The etiological factor is believed to be the interaction between genetic susceptibility, EBV infection and environmental factors, involved in the multi-step process of carcinogenesis and development of NPC. However, the molecular pathology of NPC is unclear yet. Kruppel-like factor 6(KLF6) is a ubiquitously expressed nuclear transcription factor, which is deleted and/or mutated with high frequency in a subset of prostate cancer. This study was designed to investigate KLF6 mutation in NPC tumors and NPC cell lines. METHODS: Genomic DNAs from 19 NPC tumor biospies and 3 NPC cell lines were used in mutation detection of KLF6 coding region and splice sites by PCR-sequencing. 100 chromosomes from 50 random healthy individuals were used as control. RESULTS: In 3 of 19 NPC tissues, 3 different mutations (Glu75Val, Ser136Arg, Arg243 Lys) in KLF6 gene were found by PCR-sequencing. None of the 3 mutations were detected in the 50 random healthy individuals. CONCLUSION: KLF6 gene may be involved in carcinogenesis of sporadic NPC.