Project description:Analysis of neutrophil proteomic alterations induced by migration towards inflamed joints in juvenile idiopathic arthritis (JIA). In this experiment neutrophil proteomes were investigated after migration towards JIA synovial fluid in an in vitro model of a synovial membrane, compared to neutrophils incubated in synovial fluid without migration. The migration model consisted of transwell inserts with human knee synoviocytes on the undersides and HMEC endothelial cells on the insides, placed in wells containing medium with 10 % JIA synovial fluid.
Project description:Despite ample evidence demonstrating that anterior cruciate ligament (ACL) and meniscus tears are associated with the development of knee osteoarthritis (OA), the contributing factors remain unknown. Synovial inflammation has recently been recognized as a pivotal factor in the pathogenesis of OA. However, there is a lack of data on synovial profiles after ACL or meniscus injuries, which may contribute to posttraumatic OA (PTOA). We performed RNA-seq of 3 inflamed synovial biopsy samples vs 3 normal synovial biopsy samples following ACL and/or meniscus injuries. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and protein–protein interaction (PPI) analyses were performed to investigate mRNAs with significant differences between the inflamed and normal groups.Next, competing endogenous RNA (ceRNA) networks were constructed based on bioinformatics analyses and quantitative real-time polymerase chain reaction (RT–PCR) results. The association of the identified DEGs with the levels of infiltrating immune cells was explored using Pearson correlation analysis in R software. We aimed to provide greater insights into molecular mechanisms and biologic pathways in synovitis that could regulate post-trauma osteoarthritis progression.
Project description:Neural stem/progenitor cell (NSPC) proliferation and self-renewal, as well as insult-induced differentiation, decrease markedly with age, but the molecular mechanisms responsible for these declines remain unclear. Here we show that levels of NAD+ and nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in mammalian NAD+ biosynthesis, decrease with age in the hippocampus. Ablation of Nampt in adult NSPCs reduced their pool and proliferation in vivo. The decrease in the NSPC pool during aging can be rescued by enhancing hippocampal NAD+ levels. Nampt is the main source of NSPC NAD+ levels and required for G1/S progression of the NSPC cell cycle. Nampt is also critical for oligodendrocytic lineage fate decisions through a mechanism mediated redundantly by Sirt1 and Sirt2. Ablation of Nampt in the adult NSPCs in vivo reduced NSPC-mediated oligodendrogenesis upon injury. These phenotypes recapitulate defects in NSPCs during aging, implicating Nampt-mediated NAD+ biosynthesis as a mediator of these age-associated functional declines. Total RNA obtained from neurospheres derived from postnatal hippocampi subjected to 48 hours in vitro of incubation with Nampt-specific inhibitor FK866 (10 nM, 4 samples) or vehicle (DMSO, 1:1000, 4 samples).
Project description:NAMPT is an enzyme in the mammalian NAD+ salvage pathway. Expression microarray analysis was used to study the effect of NAMPT knockdown on gene expression in MCF-7 breast cancer cells. Experiment Overall Design: Stable knockdown of NAMPT was achieved using a retroviral shRNA construct. An shRNA directed against Luciferase was used to generate the Luc control cells. Three independent biological replicates with matching Luc controls were analyzed using Affymetrix U133 A2.0 microarrays.
Project description:Hypothesis is that NAMPT overexpression alters liver transcriptomics in genetically diabetic, obese db/db mice. We treated db/db mice n = 4 with adenovirus encoding GFP or NAMPT by tail-vein delivery.
Project description:NAMPT is an enzyme in the mammalian NAD+ salvage pathway. Expression microarray analysis was used to study the effect of NAMPT knockdown on gene expression in MCF-7 breast cancer cells.
Project description:Histone H3K4 methylation is a feature of meiotic recombination hotspots shared by many organisms including plants and mammals. Meiotic recombination is initiated by programmed double strand break (DSB) formation that in budding yeast is directed in gene promoters by histone H3K4 di/trimethylation. This histone modification is indeed recognized by Spp1, a PHD-finger containing protein that belongs to the conserved histone H3K4 methyltransferase Set1 complex. During meiosis, Spp1 binds H3K4me and recruits a DSB protein, Mer2, to promote DSB formation close to gene promoters. How Set1C and Mer2 related functions of Spp1 are connected is not clear.
Project description:This study performed an in-depth investigation into the myeloid cellular landscape in the synovium of Rheumatoid Arthritis (RA) patients, ‘individuals-at-risk’ of RA and healthy controls (HC). Flow-cytometric analysis demonstrated for the first time, the presence of a CD40-expressing CD206+CD163+ macrophage population dominating the inflamed RA synovium, associated with disease-activity and treatment response. RNAseq/metabolic analysis demonstrated that this macrophage population is transcriptionally distinct, displaying unique inflammatory, and tissue-resident gene signatures, has a stable bioenergetic profile, and regulates stromal cell responses. scRNAseq profiling of 67908 RA and HC synovial-tissue cells identified nine transcriptionally distinct macrophage-clusters. IL- 1B+CCL20+ and SPP1+MT2A+ are the principal macrophage clusters in RA synovium, displaying heightened CD40 gene expression, capable of shaping stromal cell responses, and importantly are enriched pre-disease onset. Combined these findings identify the presence of an early pathogenic myeloid signature that shapes the RA joint microenvironment and represents a unique opportunity for early diagnosis and therapeutic intervention.
Project description:Neural stem/progenitor cell (NSPC) proliferation and self-renewal, as well as insult-induced differentiation, decrease markedly with age, but the molecular mechanisms responsible for these declines remain unclear. Here we show that levels of NAD+ and nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in mammalian NAD+ biosynthesis, decrease with age in the hippocampus. Ablation of Nampt in adult NSPCs reduced their pool and proliferation in vivo. The decrease in the NSPC pool during aging can be rescued by enhancing hippocampal NAD+ levels. Nampt is the main source of NSPC NAD+ levels and required for G1/S progression of the NSPC cell cycle. Nampt is also critical for oligodendrocytic lineage fate decisions through a mechanism mediated redundantly by Sirt1 and Sirt2. Ablation of Nampt in the adult NSPCs in vivo reduced NSPC-mediated oligodendrogenesis upon injury. These phenotypes recapitulate defects in NSPCs during aging, implicating Nampt-mediated NAD+ biosynthesis as a mediator of these age-associated functional declines.