Project description:Although an appropriate range of fluoride is thought to be safe and effective, excessive fluoride intake results in toxic effects in either hard tissues of teeth and skeleton or soft tissues of kidney, lung and brain. It is also well known that fluoride at a millimolar range elicits the complex cellular responses such as enzyme activity, signal transduction and apoptosis in many kinds of cells. However, its toxic effects are still unclear. In this study, to identify genes involved in cell death induced by sodium fluoride (NaF) in rat oral epithelial ROE2 cells, global-scale gene expression analysis was carried out using a GeneChip® system.
2014-01-09 | GSE53937 | GEO
Project description:The effects of sodium fluoride on the oral microbiota
Project description:Although an appropriate range of fluoride is thought to be safe and effective, excessive fluoride intake results in toxic effects in either hard tissues of teeth and skeleton or soft tissues of kidney, lung and brain. It is also well known that fluoride at a millimolar range elicits the complex cellular responses such as enzyme activity, signal transduction and apoptosis in many kinds of cells. However, its toxic effects are still unclear. In this study, to identify genes involved in apoptosis induced by sodium fluoride (NaF) in rat oral epithelial ROE2 cells, global-scale gene expression analysis was carried out using a GeneChipM-BM-. system. NaF (2 mM) significantly induced apoptosis accompaning chromatin condensation and caspase-3 activation. Total RNA samples were prepared from the NaF-treated cells, and quality of the RNA was analyzed using a Bioanalyzer 2100. Gene expression was monitored by an Affymetrix GeneChipM-BM-. system with a Rat Genome 230 2.0 array. Sample preparation for array hybridization was carried out as described in the manufacturerM-bM-^@M-^Ys instructions.
Project description:We report genome-wide transcriptome profiles of E. coli obtained in the absence (control) and presence of 20 mM and 70 mM sodium fluoride (NaF) under anaerobic conditions, and assess the impact of fluoride-dependent ATP depletion on RNA turnover. We found that transcripts with increased abundance in response to NaF treatment correspond to genes that control cell envelope and osmotic stress adaptation, signal transduction systems, lipid biosynthesis, amine and polyamine degradation as well as acquisition of iron and iron homeostasis. In contrast, downregulated genes are involved in glycolysis, fatty acid metabolism, amino acid biosynthesis, energy production, cytochrome c biogenesis, protein translocation, translation, translation factors, protein folding/processing factors, transport for amino acid, sugar, or ion, and RNA metabolism. By using a quantile-based K-means clustering approach to identify gene clusters with similar expression profiles, we identified subset (100 genes) of transcriptome whose gene expression was up- and down-regulated under fluoride and diluted fluoride conditions, respectively. In addition, we found that about 40% of the highly abundant transcripts carry repetitive extragenic palindromes (REPs). By determining the mRNA stability of osmC as well as yghA, and addressing their ribonucleases/enzymes required for RNA degradation under anaerobic conditions, we found that fluoride ions slow down RNA degradation by increasing RNA stability, in turn increasing the steady-state level of RNA. Furthermore, our results show that turnover of these REP-containing transcripts is dependent on RNase E. Collectively, our study not only reveal the effects of NaF at the whole transcriptome level under hypoxic growth conditions, but also shows that fluoride can affect gene expression post-transcriptionally by slowing down the ATP-dependent degradation of structured RNAs.
Project description:Fluoride toxicity in multiple organs has been extensively reported in several decades of research. In-depth study coverage is available on teeth and bone tissues. But studies addressing skeletal muscle fluorosis are scanty. C57BL/6 mice were provided with sodium fluoride in drinking water for 60 days. Histological analysis, primary culture of skeletal muscle was performed. Protein expressions were analyzed by Immunocytochemistry, qRT-PCR, and western blotting techniques. Proteomic approach was considered to overview the entire proteome response. Exposure to sodium fluoride resulted in the loss of body weight in C57BL/6 mice. The compactness of the myofibre arrangement was distorted due to the treatment. Major reduction of contractile proteins such as actinin, troponin, and myosin further loss of mitochondrial proteins were confirmed by proteomic approach. Sodium fluoride treatment altered mitochondrial function. Further, loss of contractile proteins triggered skeletal muscle weakness.
Project description:Though fluoride is considered an essential trace element, chronic exposure to fluoride is known to cause toxic effects. Chronic exposure of high concentration of fluoride may leads to fluorosis. To understand the molecular mechanism of fluoride induced toxicity gene expression profiling was performed on osteosarcoma cells (HOS). Cells were exposed to sub-lethal concentration of fluoride (8 ppm) for 30 days. Our result demonstrates that fluoride alters multiple biological pathways including bone development, osteoblast differentiation and apoptotic pathways.
Project description:The PIK3CA gene is frequently mutated in human cancers. To study the signaling mechanisms responsible for cell growth and invasion phenotypes induced by mutant PIK3CA molecules, we carried out a SILAC-based quantitative phosphoproteomic analysis of MCF10A, a spontaneously immortalized normal mammary epithelial cell line, and two MCF10A knockin cell lines containing different activating mutations of the PIK3CA gene. MCF10A and PIK3CA mutation knock in cells were propagated in DMEM/F12 SILAC media deficient in both L-lysine and L-arginine and supplemented with light lysine (K) and arginine (R) for light, 2H4-K and 13C6-R for medium state and 13C615N2-K and 13C615N4-R for heavy state labeling. Cell lysates were prepared in urea lysis buffer containing 20 mM HEPES pH 8.0, 9 M urea, 1 mM sodium orthovanadate, 2.5 mM sodium pyrophosphate, 1 mM ß-glycerophosphate and 5mM sodium fluoride. The lysates were reduced, alkylated and digested by trypsin. Tryptic peptides were desalted by C18 reverse phase column and followed by strong cation exchange (SCX) fractionation. Fractionated peptides were subjected to TiO2-based phosphopeptide enrichment. LC-MS/MS analysis of enriched phosphopeptides was carried out using a reverse-phase liquid chromatography system interfaced with an LTQ-Orbitrap Velos mass spectrometer. Proteome Discoverer (v 1.3) suite was used for quantitation and database searches. The tandem mass spectrometry data were searched using Mascot (2.2.0) and SEQUEST search algorithms against a Human RefSeq database supplemented with frequently observed contaminants.
2015-07-28 | PXD000599 | Pride
Project description:Effects of Silver Diamine Fluoride on the Oral Microbiome
Project description:Though fluoride is considered an essential trace element, chronic exposure to fluoride is known to cause toxic effects. Chronic exposure of high concentration of fluoride may leads to fluorosis. To understand the molecular mechanism of fluoride induced toxicity gene expression profiling was performed on osteosarcoma cells (HOS). Cells were exposed to sub-lethal concentration of fluoride (8 ppm) for 30 days. Our result demonstrates that fluoride alters multiple biological pathways including bone development, osteoblast differentiation and apoptotic pathways. HOS cells grown in MEM were treated with fluoride and total RNA was isolated from cells after 30 days exposure. Three replicates per group were used for the experiment.