Genomic effects of a nanostructured alumina insecticide in human peripheral blood lymphocytes in vitro

Nanotechnology is providing new tools for precision agriculture, such as agrochemical agents and innovative delivery mechanisms to improve cropping efficiency. Powder nanoinsecticides, such as experimental nanostructured alumina (NSA), show great potential for sustainable agriculture as an alternative to conventional synthetic pesticides because their mechanism of insecticide action is based on physical rather than on biochemical phenomena. However, even in highly non-reactive and hardly soluble substances such as alumina, reduced particle size may lead to an increased toxicity of the material. In order to determine whether NSA induces DNA and chromosomal damage, its toxicity was assessed in human peripheral blood lymphocytes (PBL) and contrasted with commercial nanostructured alumina, natural insecticide powders and a conventional pesticide. PBL from healthy donors were exposed for 24 h to increasing concentrations (50, 100 and 200 μg/mL) of NSA particle agglomerates (<350 nm); positive and negative NSA-particles, respectively; bulk Al2O3 (4.5 μm) or Diatomaceous Earth (SiO2, <4.5 μm). Alkaline comet assay and micronuclei (MNi) test were used to assess DNA damage and chromosomal breakage, respectively. Cell viability was tested with resazurin assay. Comet assay results revealed no significant increase in DNA damage by NSA compared to other natural substances. As expected, DNA breaks were significantly higher in cells exposed to an organophosphate [OPP] control (P < 0.05). No statistically significant differences were found in terms of cellular viability at 50 and 100 μg/mL of NSA but cell survival decreased at 200 μg/mL as well as in OPP group. Positively charged NSA particles significantly reduced cell viability and increased DNA migration and oxidative DNA damage (8-oxoG). NSA as well as the electrically charged NSA particles had no significant effect on MNi induction. Our results indicate that NSA particles are non-cytotoxic and non-genotoxic at the tested doses and do not cause obvious DNA damage in human PBL in vitro.Fil: Vilchez Aruani, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Valdez, Susana Ruth. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Nadin, Silvina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; Argentin

Immunization with antigenic extracts of Leishmania associated with Montanide ISA 763 adjuvant induces partial protection in BALB/c mice against Leishmania (Leishmania) amazonensis infection

Background/Purpose: A proper adjuvant has a relevant role in vaccine formulations to generate an effective immune response. In this study, total Leishmania antigen (TLA) formulated with Montanide ISA 763 or R848 as adjuvants were evaluated as a first generation Leishmania vaccine in a murine model. Methods: Immunization protocols were tested in BALB/c mice with a subcutaneous prime/boost regimen with an interval of 3 weeks. Mice immunized with unadjuvanted TLA and phosphate-buffered saline (PBS) served as control groups. On Day 21 and Day 36 of the protocol, we evaluated the humoral immune response induced by each formulation. Fifteen days after the boost, the immunized mice were challenged with 1 × 105 promastigotes of Leishmania (Leishmania) amazonensis in the right footpad (RFP). The progress of the infection was followed for 10 weeks; at the end of this period, histopathological studies were performed in the RFP. Results: Vaccines formulated with Montanide ISA 763 generated an increase in the production of immunoglobulin G (IgG; p < 0.05) compared with the control group. There were no statistically significant differences in IgG1 production between the study groups. However, immunization with TLA-Montanide ISA 763 resulted in an increase in IgG2a compared to the unadjuvanted control (p < 0.001). Also noteworthy was the fact that a significant reduction in swelling and histopathological damage of the RFP was recorded with the Montanide ISA 763 formulation. Conclusion: We conclude that the immunization of BALB/c mice with a vaccine formulated with TLA and Montanide ISA 763 generated a protective immune response against L. (L.) amazonensis, characterized by an intense production of IgG2a.Fil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Salomón, María Cristina. Universidad Nacional de Cuyo; ArgentinaFil: Celedon, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Garcia Bustos, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; ArgentinaFil: Morea, Gastón. Universidad Nacional de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Scodeller, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; Argentin

Impact of tumor necrosis factor receptor p55 deficiency in susceptibility of C57BL/6 mice to infection with Leishmania (Leishmania) amazonensis

Tumor necrosis factor (TNF) is involved in host resistance to several intracellular pathogens. Although the critical role of TNF receptor (TNFR)p55 in Leishmania (Leishmania) major infection has been demonstrated, the impact of TNFRp55 deficiency on L. (L.) amazonensis infection has not been explored. L. (L.) amazonensis-infected TNFRp55−/− mice failed to resolve lesions, whereas C57BL/6 wild-type mice completely healed. The susceptibility of the TNFRp55−/− mice was characterized by higher lesion size and histopathological damage in comparison with the wild-type mice. A marked increased of the splenic index was observed in the TNFRp55−/− mice after 15 weeks infection. These results show that in the absence of TNFRp55, L. (L.) amazonensis-infected knockout mice fail to resolve lesions, whereas wild-type mice completely heal.Fil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Salomón, María Cristina. Universidad Nacional de Cuyo; ArgentinaFil: Celedon, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Gea, Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Di Genaro, María Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Scodeller, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Changes in renal WT-1 expression preceding hypertension development

Background: Hypertension is a public health problem with mostly unknown causes, and where strong hereditary genetic alterations have not been fully elucidated. However, the use of experimental models has provided valuable information. Recent evidences suggest that alterations in key nephrogenic factors, such as Wilms' tumor 1 transcription factor (WT-1), could contribute to the development of hypertension. The aim of this paper is to evaluate the expression of WT-1 and related genes in the nephrogenic process in connection with the development of hypertension as well as the corresponding anatomical and functional correlation. Methods: Male spontaneously hypertensive and control rats were evaluated weekly from birth until week 8 of life. Their blood pressure was taken weekly using the tail-cuff blood pressure system. Weekly, 5 rats per group were sacrificed with a lethal injection of pentobarbital, and their kidneys were removed, decapsulated and weighed. The serum was collected for measuring biochemical parameters. The results were assessed using one-way analysis of variance for comparisons between groups. Results: The relationship between renal weight/total body weights was established, without significantly different values. These data were compared with apoptosis, fibrosis, number and size of the glomeruli. The elevation of systolic blood pressure was significant since week 6. Biochemical values differed slightly. Histology showed a slight increase in deposits of collagen fibers since week 4. Additionally, in kidney cortices, the expression of WT-1, heat shock protein 70 (Hsp70) and vitamin D receptors (VDR) decreased since week 4. Finally, we demonstrated ultrastructural damage to mitochondria since week 4. Conclusions: Our results would suggest an unprecedented link, possibly a regulatory mechanism, between WT-1 on nephrogenic alteration processes and their relationship with hypertension. Moreover, and previous to the increase in blood pressure, we demonstrated low expressions of WT-1, VDR and Hsp70 in kidneys from neonatal SHRs. If so, this may suggest that deregulation in the expression of WT-1 and its impact on nephrogenesis induction could be crucial in understanding the development and maintenance of hypertension.Fil: Mazzei, Luciana Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: García, Isabel Mercedes. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Calvo, Juan Pablo. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Casarotto, Mariana. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Fornes, Miguel Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Abud, María Angélica. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Ferder, León. Universidad de Puerto Rico; Puerto RicoFil: Manucha, Walter Ariel Fernando. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin

The involvement of heat shock proteins and related molecules in the resistance to therapies in breast and gynecologic cancer

The HSP response is implicated in conferring to breast and gynecologic malignancies different sensitivities to anticancer therapies including chemotherapy, endocrine therapy and immunotherapy (weare in the need of more studies about radiotherapy). The heat shock proteins are mainly implicated in cell death mechanisms, in cell differentiation including epithelial-mesenchymal transition, in tumordormancy, in angiogenesis, metastasis formation, and in the escape of immunosurveillance. Considering the ample functions where the HSPs are implicated and that the HSP response is quite complex it is not surprising that the HSP response affects the anticancer therapies. Several of the HSPs have different predominant roles according to the molecular partners with which they interact, thus it is difficult to dissect the molecular mechanisms to find the sensitivity to the therapies. In this review we present the implications of some the major HSPs (HSP27, HSP70 and HSP90) with drug resistance and present some of the main partners that are also implicated in drug resistance like p53, PTEN and MDR. We have given priority to the incorporation of clinical data where the HSPs have been studied using standard chemotherapies and new therapeutic strategies. It is clear that in order to have a significant understanding of the degree of drug resistance/sensitivity presented by a particular patient we need to examine the molecular status of several key molecular markers involved in the drug resistance pathways and that in this context the study of the HSP response should be incorporated. One of the other major problems in this field is that an inhibitor of one particular HSP will not be enough to achieve a significant anticancer response. Now that we know the complexity of this field we need to design strategies aiming to inhibit several molecular HSP pathways simultaneously without significantly affecting the normal cells, this is the principal challenge for the near future.Fil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Fanelli, Mariel Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Castro, Gisela Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cayado Gutiérrez, Niubys de Los Milagros. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Ciocca, Daniel Ramon. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Differential expression and localization of beta-catenin and HSP27 after cisplatin/doxorubicin treatment in triple negative breast cancer cells

The treatment of triple-negative breast cancers involves the administration of the conventional chemotherapeutic drug doxorubicin, given the lack of specific targeted agents. Novel therapeutic strategies, such as cisplatin, are currently being tested for these patients. Many studies have demonstrated that aberrant Wnt/β-catenin signaling serves a role in the development of breast cancer, while others have concluded that abnormal regulation of Wnt pathway induces tumor cell chemoresistance. The small heat shock protein 27 (HSP27) is overexpressed in human breast cancer cells. As a result, cancer cells may suppress apoptosis and develop resistance to antineoplastic agents, such as doxorubicin. The present study sought to examine the role of the Wnt/β-catenin and HSP27 signaling pathway in response to cisplatin (CisPt)/doxorubicin (Doxo) treatment in human triple-negative (TN) breast cancer cell lines. Material and Methods: MDA-MB231 (TN) and MCF10A cell lines were used. Cell viability was measured using MTT assay and IC50 values were obtained after 48 h of CisPt or Doxo exposition. β-catenin and Hsp27 gene expression were measured by qPCR. Total and active β-catenin, phosphor ant total HSP27, phospho and GSK3β, phosphor and total p38 expressions were measured by western blot and immunofluorescence. 3D cell culture from MDA MB231 cells were treated with increasing concentrations of CisPt and Doxo for 48h. Results: MDA-MB231 cells showed higher IC50 values for CisPt and Doxo than the MCF10A cell line. In MDA-MB231 cells, the expression of β-catenin, active β-catenin, total and phospho-GSK3β and total HSP27 significantly decreased in the CisPt group (p<0.05). No changes were observed in Doxo-treated group. In MCF10A cells, the expression levels of total and active β-catenin did not modify with CisPt treatment, but in the Doxo group the proteins evaluated showed a tendency to increase. Also in MCF10A Doxo treatment significantly decreased the expression of GSK3β in comparison with control (p<0.05). In contrast, CisPt administration significantly increased phospho-GSK3β expression respect to the control group (p<0.05). Interestingly, in MDA-MB231 cells the nucleolus appeared disaggregated and active β-catenin increased at this subcellular localization after CisPt and Doxo treatment. In contrast, total β-catenin was preferentially localized in the Golgi. In the other hand 3D cell culture was more resistant to Doxo-treatment than 2D cell culture. CisPt induced a decrease in 3D cell culture growth. Conclusions: CisPt treatment was associated with decreased expression of β-catenin and HSP27. While in Doxo-treated cells, as related to stable levels of β-catenin and increased expression of HSP27. The differential expression and localizations of β-catenin and HSP27 could be related to a differential cellular response depending on the cytotoxicity mechanism of chemotherapeutic agent used., that in turns affect the cell fate decision. Our preliminary data indicate that β-catenin and HSP27 may be potential therapeutic targets in TNBC.Fil: Córdoba, María Evelyn. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Pennacchio, Gisela Erika. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cayado Gutiérrez, Niubys de Los Milagros. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Nadin, Silvina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Vargas Roig, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Fanelli, Mariel Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaXXXVII Reunión Científica Anual de la Sociedad de Biología de CuyoSan LuisArgentinaSociedad de Biología de Cuy

Anti-inflammatory, antioxidant, antihypertensive, and antiarrhythmic effect of indole-3-carbinol, a phytochemical derived from cruciferous vegetables

Background: Cardiovascular inflammation and oxidative stress are determining factors in high blood pressure and arrhythmias. Indole-3-carbinol is a cruciferous-derived phytochemical with potential anti-inflammatory and antioxidant effects. However, its implications on the modulation of cardiovascular inflammatory-oxidative markers are unknown. Objectives: To establish the effects of indole-3-carbinol on the oxidative-inflammatory-proarrhythmic conditions associated with hypertension. Materials: Histological, biochemical, molecular, and functional aspects were evaluated in 1) Culture of mouse BV-2 glial cells subjected to oxidative-inflammatory damage by lipopolysaccharides (100 ng/mL) in the presence or absence of 40 μM indole-3-carbinol (n = 5); 2) Male spontaneously hypertensive rats (SHR) and Wistar Kyoto rats receiving indole-3-carbinol (2000 ppm/day, orally) during the first 8 weeks of life (n = 15); 3) Isolated rat hearts were submitted to 10 min regional ischemia and 10 min reperfusion. Results: 1) lipopolysaccharides induced oxidative stress and increased inflammatory markers; indole-3-carbinol reversed both conditions (interleukin 6, tumor necrosis factor α, the activity of nicotinamide adenine dinucleotide phosphate oxidase, nitric oxide, inducible nitric oxide synthase, heat shock protein 70, all p < 0.01 vs lipopolysaccharides). 2) SHR rats showed histological, structural, and functional changes with increasing systolic blood pressure (154 ± 8 mmHg vs. 122 ± 7 mmHg in Wistar Kyoto rats, p < 0.01); Inflammatory-oxidative markers also increased, and nitric oxide and heat shock protein 70 decreased. Conversely, indole-3-carbinol reduced oxidative-inflammatory markers and systolic blood pressure (133 ± 8 mmHg, p < 0.01 vs. SHR). 3) indole-3-carbinol reduced reperfusion arrhythmias from 8/10 in SHR to 0/10 (p = 0.0007 by Fisher's exact test). Conclusions: Indole-3-carbinol reduces the inflammatory-oxidative-proarrhythmic process of hypertension. The nitric oxide and heat shock protein 70 are relevant mechanisms of indole-3-carbinol protective actions. Further studies with this pleiotropic phytochemical as a promising cardioprotective are guaranteed.Fil: Prado, Natalia Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Ramirez, Daniela Andrea. Laboratorio de Cromatografía Para Agroalimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Mazzei, Luciana Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Parra, Micaela. Universidad Nacional de Cuyo; ArgentinaFil: Casarotto, Mariana. Universidad Nacional de Cuyo; ArgentinaFil: Calvo, Juan Pablo. Universidad Nacional de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Ponce Zumino, Amira Zulma. Universidad Nacional de Cuyo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Diez, Emiliano Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Camargo, Alejandra Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Manucha, Walter Ariel Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad del Aconcagua. Facultad de Ciencias Médicas; Argentin

In MMTV-Her-2/neu transgenic mammary tumors the absence of caveolin-1−/− alters PTEN and NHERF1 but not β-catenin expression

In a recent study, we have shown that in mammary tumors from mice lacking the Cav-1 gene, there are alterations in specific heat shock proteins as well as in tumor development. With this in mind, we have now investigated other proteins in the same mammary mouse tumor model (Her-2/neu expressing mammary tumors from Cav-1 wild type and Cav-1 null mice), to further comprehend the complex tumor-stroma mechanisms involved in regulating stress responses during tumor development. In this tumor model the cancer cells always lacked of Cav-1, so the KO influenced the Cav-1 in the stroma. By immunohistochemistry, we have found a striking co-expression of β-catenin and Her-2/neu in the tumor cells. The absence of Cav-1 in the tumor stroma had no effect on expression or localization of β-catenin and Her-2/neu. Both proteins appeared co-localized at the cell surface during tumor development and progression. Since Her-2/neu activation induces MTA1, we next evaluated MTA1 in the mouse tumors. Although this protein was found in numerous nuclei, the absence of Cav-1 did not alter its expression level. In contrast, significantly more PTEN protein was noted in the tumors lacking Cav-1 in the stroma, with the protein localized mainly in the nuclei. P-Akt levels were relatively low in tumors from both Cav-1 WT and Cav-1 KO mice. There was also an increase in nuclear NHERF1 expression levels in the tumors arising from Cav-1 KO mice. The data obtained in the MMTV-neu model are consistent with a role for Cav-1 in adjacent breast cancer stromal cells in modulating the expression and localization of important proteins implicated in tumor cell behavior.Fil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cayado Gutiérrez, Niubys de Los Milagros. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Natoli, Anthony L. . Peter MacCallum Cancer Centre. Metastasis Research Laboratory; AustraliaFil: Restall, Christina. Peter MacCallum Cancer Centre. Metastasis Research Laboratory; AustraliaFil: Anderson, Robin L.. Peter MacCallum Cancer Centre. Metastasis Research Laboratory; AustraliaFil: Nadin, Silvina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Alvarez Olmedo, Daiana Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Castro, Gisela N.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Gago, Francisco E.. Facultad de Ciencias Médicas. Universidad Nacional de Cuyo; ArgentinaFil: Fanelli, Mariel Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Ciocca, Daniel Ramon. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Experimental hypothyroidism increases apoptosis in dimethylbenzanthracene-induced mammary tumors

Epidemiological and in vitro data have not provided conclusive evidence concerning the involvement of thyroid hormones (THs) on mammary carcinogenesis. We used an in vivo model to assess the relationship between THs, adipose tissue and breast cancer development. Female Sprague‑Dawley rats were treated with a dose of 7,12-dimethylbenz(a)anthracene (15 mg/rat) at 55 days of age and were then divided into four experimental groups: hypothyroid rats (HypoT, 0.01% 6-N-propyl-2-thiouracil in drinking water), untreated control (EUT); hyperthyroid rats (HyperT, 0.25 mg/kg/day T4 s.c.) and vehicle-treated control rats. The latency of tumor appearance and the incidence and progression of tumors were determined. At sacrifice, blood samples were collected for hormone determinations and samples of tumor and mammary glands were obtained for immunohistological studies. HypoT rats had retarded growth and an increase in mammary fat. The latency was longer (p<0.0001), the incidence rate was lower (p<0.05) and tumor growth was slower in HypoT rats compared to EUT and HyperT rats. Mitotic index and PCNA immunostaining were similar in all groups. HypoT rats showed increased apoptosis (p<0.05) as evaluated by the apoptotic index and TUNEL staining. No differences in serum prolactin and progesterone were observed. However, circulating estradiol (E2) was significantly lower in HypoT and HyperT rats. Serum leptin levels were reduced in HypoT rats even though the abdominal fat mass was similar in all groups. To note, the leptin level was higher in HypoT rats that developed mammary tumors than the level in non-tumoral HypoT rats. In conclusion, hypothyroidism altered animal growth, breast morphology, body composition, leptin secretion and serum E2 enhancing apoptosis and, consequently, retarding mammary carcinogenesis in rats.Fil: López Fontana, Constanza Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Sasso, Corina Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Maselli, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Santiano, Flavia Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Semino, Silvana Noemi. Universidad Nacional de Cuyo. Hospital Universitario. Laboratorio de Anatomía Patológica; Argentina;Fil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina;Fil: Caron, Ruben Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina

Heat shock protein 70/nitric oxide effect on stretched tubular epithelial cells linked to WT-1 cytoprotection during neonatal obstructive nephropathy

Background Mechanical stress is a key pathogenic driver of apoptosis in the tubular epithelium in obstructive nephropathy. Heat shock protein 70 (Hsp70) and Wilms’ tumor (WT-1) have been proposed to represent linked downstream effectors of the cytoprotective properties of NO. In the present study, we sought to evaluate whether the cytoprotective effects of l-arginine in neonatal obstructive nephropathy may be associated with NO-dependent increases in WT-1 and Hsp70 expression. Methods Neonatal Wistar–Kyoto rats were submitted to complete unilateral ureteral obstruction (UUO) and treated thereafter with vehicle, L-NAME or l-arginine by daily gavage for 14 days to block or augment NO levels, respectively. Normal rat kidney epithelial cells by NRK-52E were exposed to mechanical stress in vitro in the presence or absence of L-NAME, l-arginine, sodium nitroprusside (SNP), l-arginine + SNP or l-arginine/L-NAME. Induction of apoptosis and the mRNA expression of WT-1 and Hsp70 genes were assessed. Results WT-1 and Hsp70 genes expression decreased in the presence of L-NAME and following UUO coincident with increased tubular apoptosis. l-arginine treatment increased NO levels, reduced apoptosis and restored expression levels of WT-1 and Hsp70 to control levels. l-arginine treatment in vitro reduced basal apoptotic rates and prevented apoptosis in response to mechanical strain, an effect enhanced by SNP co-incubation. L-NAME increased apoptosis and prevented the anti-apoptotic action of l-arginine. Conclusions l-arginine treatment in experimental neonatal UUO reduces apoptosis coincident with restoration of WT-1 and Hsp70 expression levels and directly inhibits mechanical strain-induced apoptosis in an NO-dependent manner in vitro. This potentially implicates an NO-Hsp70-WT-1 axis in the cytoprotective effects of l-arginine.Fil: Mazzei, Luciana Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Cuello Carrión, Fernando Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Docherty, Neil. University College Dublin; IrlandaFil: Manucha, Walter Ariel Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin