Asparagine alleviates naphthalene-induced lens opacity in SRA cells
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ABSTRACT: Cataract is characterized by lens opacity, often leading to vision loss. The primary clinical treatment is lens replacement, which usually yields good results. Although cataract surgery is a common ophthalmic treatment, it still carries surgical risks, such as infection, bleeding, and dislocation of the intraocular lens. Therefore, researching drugs that can delay or treat cataract holds significant social and scientific importance. This study found that asparagine can improve lens opacification in rats exposed to naphthalene. Consequently, in vitro, SRA01/04 cells were treated with the naphthalene metabolite 1,2 - dihydroxynaphthalene (1,2 - DHN), and RNA - sequencing technology was employed to investigate the cellular mechanisms underlying the therapeutic effects of asparagine.Through systematic experiments and analyses, we have dissected the cellular changes following treatment with 1,2 - DHN, comprehensively presenting the molecular network affected thereby. Simultaneously, we have also paid particular attention to the signaling pathways activated by Asn during this process.
Project description:The epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) has been proposed as a major cause of posterior capsule opacification (PCO) after cataract surgery. Molecular mechanism of PCO progression is still unclear. Using a microarray-based approach, herein we studied the changes in gene expression pattern during rat PCO formation in vivo as a model.
Project description:Cold cataract is the reversible opacification of the lens when the temperature decreases. However, we observed that when temperature of the rats lens was maintained at a lower temperature for a prolonged time, the opacification of lens was only partly reversible. To review the potential molecular mechanism of the irreversible part of opacification under cold stimulation, we applied comparative transcriptomic and proteomic analysis to systematically investigate the molecular changes that occurred in the lens capsules of rats under low temperature treatments. The RNA sequencing based transcriptomic analysis showed a significant up-regulation of genes related to the lens structure and development in the Hypothermia Group. Hub genes were small heat shock proteins (sHSPs). Besides the same findings as the transcriptomic results, the liquid chromatography-tandem mass spectrometry based proteomic analysis also revealed the up-regulation of the apoptotic process. To further analyze the regulatory mechanism in this process, we subsequently performed integrated analysis and identified the down-regulation of Notch3/Hes1 and PI3K/Akt/Xiap signaling axis. Our research revealed the activation of the apoptotic process in rats lens under cold stimulation, and the sHSP related heat shock response as a potential protective factor through our transcriptomic and proteomic data.
Project description:Degradation of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene by anaerobic microorganisms is poorly understood. Strain NaphS2, an anaerobic sulfate reducing marine delta-proteobacterium is capable of using naphthalene and the aromatic compound benzoate, as well as pyruvate, as an electron donors in the presence of sulfate. In order to identify genes involved in the naphthalene degradation pathway, we compared gene expression in NaphS2 during growth on benzoate vs. pyruvate, naphthalene vs. pyruvate, and naphthalene vs benzoate.
Project description:Although majority of the genes linked to pediatric cataract exhibit lens fiber cell-enriched expression, our understanding of gene regulation in these cells is limited to function of just eight transcription factors and largely in the context of crystallins. Here, we identify small Maf transcription factors MafG and MafK as regulators of several non-crystallin human cataract genes in fiber cells and establish their significance to cataract. We applied a bioinformatics tool for cataract gene discovery iSyTE to identify MafG and its co-regulators in the lens, and generated various null-allelic combinations of MafG:MafK mouse mutants for phenotypic and molecular analysis. By age 4-months, MafG-/-:MafK+/- mutants exhibit lens defects that progressively develop into cataract. High-resolution phenotypic characterization of MafG-/-:MafK+/- lens reveals severe defects in fiber cells, while microarrays-based expression profiling identifies 97 differentially regulated genes (DRGs). Integrative analysis of MafG-/-:MafK+/- lens-DRGs with 1) binding-motifs and genomic targets of small Mafs and their regulatory partners, 2) iSyTE lens-expression data, and 3) interactions between DRGs in the String database, unravels a detailed small Maf regulatory network in the lens, several nodes of which are linked to human cataract. This analysis prioritizes 36 highly promising candidates from the original 97 DRGs. Significantly, 8/36 (22%) DRGs are associated with cataracts in human (GSTO1, MGST1, SC4MOL, UCHL1) or mouse (Aldh3a1, Crygf, Hspb1, Pcbd1), suggesting a multifactorial etiology that includes elevation of oxidative stress. These data identify MafG and MafK as new cataract-associated candidates and define their function in regulating largely non-crystallin genes linked to mouse and human cataract. Microarray comparision of lenses from mixed background (129Sv/J, C57BL/6J, and ICR) control (MafG+/-:MafK+/-; no-cataract) and compound (MafG-/-:MafK+/-; cataract) mouse mutants
Project description:<p><strong>INTRODUCTION:</strong> Metabolites are essential for the proper functioning of the eye lens, they either enter the lens from the aqueous humor (AH), or are synthesized in the lens epithelium. Antioxidants, osmolytes and UV filters are especially important for the lens protection, and their lack may cause the development of ophthalmic diseases.</p><p><strong>OBJECTIVES:</strong> Comparison of the metabolomic compositions of lenses and AH taken from cataract patients with that taken from human cadavers without cataract can shed light onto molecular mechanisms underlying onset of age-related nuclear cataract.</p><p><strong>METHODS:</strong> Combined use of 1H nuclear magnetic resonance and high performance liquid chromatography with optical and high-resolution mass spectrometric detection for the identification and quantification of metabolites in the lens and AH extracts.</p><p><strong>RESULTS:</strong> The concentrations of 86 metabolites were determined for four groups of samples, including lenses and AH from cataract patients and from human cadavers. In cataractous lens the most abundant metabolites are (in descending order): myo-inositol, lactate, acetate, glutamate, glutathione; in AH-lactate, glucose, glutamine, alanine, valine. The concentrations of the majority of metabolites in normal post-mortem samples of both lens and AH are higher than that in samples from the cataract patients.</p><p><strong>CONCLUSIONS:</strong> Comparison of metabolite concentrations in lens and corresponding AH reveal that the most important for the lens protection metabolites are synthesized in the lens epithelial cells. The reduced levels of antioxidants, UV filters, and osmolytes were found in the cataractous lenses what cannot be explained by post-mortem changes in normal lens; that indicates that the age-related nuclear cataract development may originate from the dysfunction of the lens epithelial cells.</p>
Project description:Degradation of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene by anaerobic microorganisms is poorly understood. Strain NaphS2, an anaerobic sulfate reducing marine delta-proteobacterium is capable of using naphthalene and the aromatic compound benzoate, as well as pyruvate, as an electron donors in the presence of sulfate. In order to identify genes involved in the naphthalene degradation pathway, we compared gene expression in NaphS2 during growth on benzoate vs. pyruvate, naphthalene vs. pyruvate, and naphthalene vs benzoate. For each experimental set, aRNA from NaphS2 was labelled Cy5 (experiment) or Cy3(control) with three biological replicates hybridized in duplicate. In addition, because of the size of the predicted genome of NaphS2, ORFs were divided into two separate array designs, designated set1 and set2, such that set1 and set2 represent two separate array designs (probe sets) to be treated separately in statistical analysis.
Project description:The Shumiya cataract rat (SCR) is a model for hereditary cataract. Two-third of these rats develop lens opacity within 10-11-weeks. Onset of cataract is attributed to the synergetic effect of lanosterol synthase (Lss) and farnesyl-diphosphate farnesyltransferase 1 (Fdft1) mutant alleles that lead to cholesterol deficiency in the lenses, which in turn adversely affects lens biology including the growth and differentiation of lens epithelial cells (LECs). Nevertheless, the molecular events and changes in gene expression associated with the onset of lens opacity in SCR is poorly understood. Our study aimed to identify the gene expression patterns during cataract formation in SCRs, which may be responsible for cataractogenesis in SCR.
Project description:Plasmid-free Pseudomonas putida KT2440 compared with the same strain harbouring NAH7 plasmid; all the cells were grown in minimal medium (M9 with glucose) saturated with naphthalene.
Project description:Transcriptomic analysis on naphthalene exposed mouse lung cells was performed to discover molecular biomarkers for environmental toxin responses in respiratory orgnas. DEG analysis revelaed 293 genes with significant expression changes in naphthalene treated samples. GO enrichment analysis result showed GO terms related to cillum, axoneme and dynein complex were enriched in down-regulated genes and stress response terms in up-regulated genes. These results indicate when exposed to naphthalene, genes with increased expression levels are associated with chemical response and inflammation, while genes with decreased expression levels are associated with pseudostratified epithelical cells in respiratory organ.