RESUMEN
Cadmium (Cd) is a carcinogen with several well-described toxicological effects in humans, but its molecular mechanisms are still not fully understood. Overexpression of heat shock protein 27 (HSP27/HSPB1)-a multifunctional protein chaperone-has been shown to protect cells from oxidative damage and apoptosis triggered by Cd exposure. The aims of this work were to investigate the potential use of extracellular recombinant HSP27 to prevent/counteract Cd-induced cellular toxicity and to evaluate if peroxynitrite was involved in the development of Cd-induced toxicity. Here, we report that the harmful effects of Cd correlated with changes in oxidative stress markers: upregulation of reactive oxygen species, reduction in nitric oxide (NO) bioavailability, increment in lipid peroxidation, peroxynitrite (PN), and protein nitration; intracellular HSP27 was reduced. Treatments with Cd (100 µM) for 24 h or with the peroxynitrite donor, SIN-1, decreased HSP27 levels (~50%), suggesting that PN formation is responsible for the reduction of HSP27. Pre-treatments of the cells either with Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) (a pharmacological inhibitor of NO synthase) or with recombinant HSP27 (rHSP27) attenuated the disruption of the cellular metabolism induced by Cd, increasing in a 55 and 52%, respectively, the cell viability measured by CCK-8. Cd induced necrotic cell death pathways, although apoptosis was also activated; pre-treatment with L-NAME or rHSP27 mitigated cell death. Our findings show for the first time a direct relationship between Cd-induced toxicity and PN production and a role for rHSP27 as a potential therapeutic agent that may counteract Cd toxicity.
Asunto(s)
Cadmio/toxicidad , Proteínas de Choque Térmico HSP27/metabolismo , Estrés Oxidativo/efectos de los fármacos , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Femenino , Colorantes Fluorescentes/química , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/farmacología , Células HeLa , Humanos , Microscopía Fluorescente , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Ácido Peroxinitroso/análisis , Ácido Peroxinitroso/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología , Regulación hacia Arriba/efectos de los fármacos , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patologíaRESUMEN
Suboptimal intake of Zinc (Zn) is one of the most common worldwide nutritional problems. The aim of this study is to provide new evidence on the relation between moderate Zn restriction, and cytoprotective functions in airway epithelium. We analyzed the effect of moderate Zn deficiency (ZD) on the expression of several pro and anti-apoptotic proteins and cytoprotective factors (Hsp27 and Hsp 70i), as well as the effect of restoring Zn during the refeeding period. Adult male rats were divided into three groups: Zn-adequate control group, Zn-deficient group and Zn-refed group. Our previous findings showed an important oxidative and nitrosative stress during ZD, this situation is accompanied by inflammation and alterations in the expression of matrix extracellular proteins. We observed a strong immunopositive area of anti and pro-apoptotics proteins in ZD groups. The mRNA levels of Nrf-2, Bax and Bad were increased in ZD, while in ZD refed group its levels were similar to the control values. The increased expression of Nrf-2 is likely to be critical for protection of lung under inflammatory process triggered during ZD. Hsp27 and Hsp 70i showed an increase of immunostaining area but they were not significant. During the supplementation period, heat-shock proteins increased significantly. In conclusion, our results provide further evidence of the pathways involved in cytoprotection and apoptosis caused by ZD. Additional studies are required in order to investigate whether Hsp27 and Hsp70 are consistently associated with cellular stress and inflammation in lung. There may be a beneficial role for improved Zn nutrition or Zn supplements early in lung pathology.
Asunto(s)
Citoprotección , Células Epiteliales/citología , Pulmón/citología , Zinc/deficiencia , Animales , Apoptosis/efectos de los fármacos , Citoprotección/genética , Dieta , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Proteínas de Choque Térmico HSP27/análisis , Proteínas de Choque Térmico HSP27/biosíntesis , Proteínas HSP70 de Choque Térmico/análisis , Proteínas HSP70 de Choque Térmico/biosíntesis , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Masculino , Ratas , Ratas Wistar , Zinc/administración & dosificación , Zinc/farmacologíaRESUMEN
Suboptimal intake of Zn is one of the most common nutritional problems worldwide. Previously, we have shown that Zn deficiency (ZD) produces oxidative and nitrosative stress in the lung of rats. We analyse the effect of moderate ZD on the expression of several intermediate filaments of the cytoskeleton, as well as the effect of restoring Zn during the refeeding period. Adult male rats were divided into three groups: Zn-adequate control (CO) group; ZD group; Zn-refeeding group. CerbB-2 and proliferating cell nuclear antigen (PCNA) expression was increased in the ZD group while the other parameters did not change. During the refeeding time, CerbB-2, cytokeratins, vimentin and PCNA immunostaining was higher than that in the CO group. The present findings indicate that the overexpression of some markers could lead to the fibrotic process in the lung. Perhaps ZD implications must be taken into account in health interventions because an inflammation environment is associated with ZD in the lung.
Asunto(s)
Matriz Extracelular/química , Matriz Extracelular/metabolismo , Pulmón/metabolismo , Zinc/deficiencia , Animales , Biomarcadores/análisis , Peso Corporal , Cadherinas/química , Cadherinas/metabolismo , Regulación de la Expresión Génica , Inmunohistoquímica , Queratinas/química , Queratinas/metabolismo , Masculino , Ratas , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
Suboptimal intake of dietary zinc (Zn) is one of the most common nutritional problems worldwide. Previously, the authors have shown that zinc deficiency (ZD) produces oxidative and nitrosative stress in lung of male rats. The goal of this study is to test the effect of moderate ZD on insulin-like growth factor (IGF)-1, IGF-binding protein (IGFBP)-5, NADH oxidase (NOX)-2, tumor necrosis factor alpha (TNFalpha), as well as the effect of restoring zinc during the refeeding period. Adult male rats were divided into 3 groups: Zn-adequate control group, Zn-deficient group, and Zn-refeeding group. eNOS, metallothionein (MT) II, and NOX-2 was increased in ZD group. The authors observed an increased gene transcription of superoxide dismutase (SOD)-2 and gluthathione peroxidase (GPx)-1 in ZD group, as well as in ZD-refeeding group, but catalase (CAT) transcription did not change in the treated groups. Proinflammatory factors, such as TNFalpha and vascular cell adhesion molecular (VCAM)-1 increased in ZD, whereas it decreased in ZD refeeding. However, peroxisome proliferator-activated receptor gamma (PPARgamma) and IGF-1 gene transcription decreased in ZD, whereas IGFBP-5 decreased in the ZD group. These parameters are associated to alterations in the lung histoarchitecture. The zinc supplementation period is brief (only 10 days), but it is enough to inhibit some proinflammatory factors. Perhaps, zinc deficiency implications must be taken into account in health interventions because inflammation and prooxidant environment are associated with ZD in lung.
Asunto(s)
Regulación de la Expresión Génica , Inflamación/etiología , Pulmón/patología , Desnutrición/patología , Estrés Oxidativo , Zinc/deficiencia , Animales , Biomarcadores/análisis , Perfilación de la Expresión Génica , Inflamación/diagnóstico , Inflamación/tratamiento farmacológico , Pulmón/metabolismo , Masculino , Desnutrición/metabolismo , Ratas , Zinc/uso terapéuticoRESUMEN
Reactive oxygen and nitrogen species have been implicated in the pathogenesis of pulmonary diseases. The goal of this study was to measure the response of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 enzymes (COX-2) in lung with moderate zinc deficiency. Adult male Wistar rats were divided into two groups receiving (1) a zinc-deficient diet (ZD) or (2) a zinc-adequate control diet. After 2 months of treatment, the zinc-deficient group showed a significant pulmonary edema. This was associated to a reduction of protein thiols and to a significant increase of metallothionein and glutathione disulfide levels. In addition, a higher serum and lung NO production in ZD group was positively related to the higher activity and expression of iNOS and COX-2 found in lungs. Western blot analysis revealed increased IkappaBalpha degradation, an indicator of NF-kappaB activation in ZD lungs. Anatomopathologic analysis of ZD lungs showed an increase of connective tissue fibers with an influx of polymorphonuclear cells. These cells and type II cells from the alveoli showed specific immunohistochemical signals for iNOS. The conclusion is that, during the development of zinc-deficiency, iNOS activity increases in lung and contributes to lung injury. Zinc deficiency implications must be taken into account to design therapies and public health interventions involving targeted zinc supplementation for high-risk subjects or certain diseases, such as asthma.