Efecto de las nanopartículas industriales TiO 2 , SiO 2 y ZnO sobre la viabilidad celular y expresión génica en médula ósea roja de mus musculus / Effect of the Industrial Nanoparticles TiO 2 , SiO 2 and ZnO on Cell Viability and Gene Expression in Red Bone Marrow of Mus Musculus

RESUMEN Objetivos Evaluar el efecto de las nanopartículas de ZnO, TiO2 y SiO2 sobre la viabilidad celular y la expresión génica de las interleuquinas 7 y 3 y del factor estimulante de colonias de granulocito - macrófago (GM-CSF) en Mus musculus. Materiales y métodos Se extrajo médula ósea roja de cinco roedores (Balb/c) para el estudio de viabilidad celular mediante la prueba de MTT. Por otro lado, grupos cinco roedores fueron inoculados vía intraperitoneal con dosis de 0,5; 1; 2,5; 5 y 10 mg/kg de nanopartículas de ZnO y SiO2 y de 5; 10; 15; 20 y 25 mg/kg de nanopartículas de TiO2, 30 h después, se obtuvo el ARN a partir de la médula ósea roja para los análisis de expresión génica empleando las técnicas de PCR y RT-PCR cuantitativa. Resultados Las nanopartículas de ZnO y SiO2 redujeron la viabilidad celular de una manera dosis-dependiente en un 37 y 26%, respectivamente, a partir de una dosis de 1 mg/kg. En cuanto al efecto sobre la expresión génica, a las dosis 5 y 10 mg/kg, las nanopartículas de TiO2 redujeron en mayor porcentaje la expresión de las interleuquinas 7 y 3 (55,3 y 70,2% respectivamente), con respecto a la expresión del GM-CSF, el mayor porcentaje de reducción lo produjo las nanopartículas de SiO2 (91%). Las nanopartículas de ZnO redujeron a partir de las dosis de 20 y 25 mg/kg. Conclusiones Las nanopartículas de ZnO, SiO2 y TiO2 alteran la viabilidad celular y la expresión génica en la médula ósea de ratón.

ABSTRACT Objectives To evaluate the effect of ZnO, TiO2 and SiO2 nanoparticles on cell viability and expression of the interleukin 7, interleukin 3, and granulocyte-macrophage colony stimulating factor (GM-CSF) genes in Mus musculus. Material and methods Red bone marrow was extracted from five Balb/c mice for the analysis of cell viability using the MTT test. The mice were divided into two groups of five each: one group was inoculated intraperitoneally with 0.5, 1.0, 2.5, 5.0, and 10 mg/kg of ZnO and SiO2 nanoparticles, respectively, and the other group was inoculated with 5.0, 10.0, 15.0, 20.0, and 25 mg/kg of TiO2 nanoparticles, respectively. Thirty hours later, RNA was extracted from the red bone marrow of the mice in both groups for gene expression analysis using quantitative PCR and RT-PCR. Results ZnO and SiO2 nanoparticles reduced cell viability in a dose-dependent manner by 37% and 26%, respectively, starting at a dose of 1 mg/kg. TiO2 nanoparticles at 5 mg/kg and 10 mg/kg reduced the gene expression of interleukins 7 and 3 by 55.3% and 70.2%, respectively, and SiO2 nanoparticles caused the greatest decrease (91%) in the expression of GM-CSF. ZnO nanoparticles reduced the expression of GM-CSF starting at doses of 20 mg/kg and 25 mg/kg. Conclusions ZnO, SiO2 and TiO2 nanoparticles affect cell viability and gene expression in the mouse bone marrow.

Association of interleukin-4 and interleukin-17F polymorphisms in periodontitis in Dravidian ethnicity.

BACKGROUND: Complex network of pro and anti-inflammatory cytokines are known to act in inflamed periodontal tissue. This study explores the distribution of interleukin (IL)-4 (+33 C/T) and IL-17F (7383A/G, 7488A/G) gene polymorphism in chronic and aggressive periodontitis subjects of Dravidian ethnicity. MATERIALS AND METHODS: This case control study consisted of 124 periodontitis individuals comprising of 63 chronic and 61 aggressive periodontitis subjects as cases, and control group consisted of 101 healthy subjects. All subjects were genotyped for IL-4 + 33C/T, IL-17F 7383A/G, 7488A/G by polymerase chain reaction amplification followed by TaqMan assay for IL-4 + 33C/T, restriction enzyme digestion and gel electrophoresis for IL-17F 7383A/G and sequencing for IL-17F 7488A/G. RESULTS: IL-4 + 33C/T was significantly associated with periodontitis (P < 0.05) at both allelic and genotypic level. In subgroup analysis also significant difference (P < 0.05) in allelic distribution between aggressive periodontitis and control group for loci IL-4 + 33C/T was noted. However, there was a lack of association between IL-17F 7383A/G and IL-17F 7488A/G with periodontitis and its sub-groups at both allelic and genotypic levels. CONCLUSIONS: In Malayalam speaking Dravidian population IL-4 + 33C/T loci appears to be an important risk factor for periodontal disease with a leaning towards aggressive periodontitis. The association between IL-17F at 7383A/G and 7488A/G loci with either chronic or an aggressive periodontitis could not be ascertained.

RANKL stimulates proliferation, adhesion and IL-7 expression of thymic epithelial cells

Abstract In many clinical situations which cause thymic involution and thereby result in immune deficiency, T cells are the most often affected, leading to a prolonged deficiency of T cells. Since only the thymic-dependent T cell production pathway secures stable regeneration of fully mature T cells, seeking strategies to enhance thymic regeneration should be a key step in developing therapeutic methods for the treatment of these significant clinical problems. This study clearly shows that receptor activator of NF-kappaB ligand (RANKL) stimulates mouse thymic epithelial cell activities including cell proliferation, thymocyte adhesion to thymic epithelial cells, and the expression of cell death regulatory genes favoring cell survival, cell adhesion molecules such as ICAM-1 and VCAM-1, and thymopoietic factors including IL-7. Importantly, RANKL exhibited a significant capability to facilitate thymic regeneration in mice. In addition, this study demonstrates that RANKL acts directly on the thymus to activate thymus regeneration regardless of its potential influences on thymic regeneration through an indirect or systemic effect. In light of this, the present study provides a greater insight into the development of novel therapeutic strategies for effective thymus repopulation using RANKL in the design of therapies for many clinical conditions in which immune reconstitution is required.