Project description:To investigate how the pattern of gene expression is changed in endothelial cells by cellular senescence, RNA-seq analysis was carried out with human umbilical vein endothelial cells(HUVECs)
Project description:Cellular senescence is a key cell-fate program that leads to an essentially irreversible proliferative arrest in potentially damaged cells. Cytokine production and signaling play a significant role in senescence. Tumor necrosis factor-alpha (TNFα), an important pro-inflammatory cytokine secreted by some senescent cells, can induce senescence in mouse and human cells. However, downstream signaling pathways and key regulatory genes linking inflammation to senescence are not fully characterized. Using human umbilical vein endothelial cells (HUVECs) as a model, we show TNFα induces permanent growth arrest and increased senescence markers such as p21, p16, and senescence-associated β-galactosidase (SA-β-gal), accompanied by persistent DNA damage and ROS. By gene expression profiling and pathway analysis, we identify the crucial involvement of inflammatory networks, an interferon signature, and persistent activation of the Janus kinase (JAK) /signal transducer and activator of transcription (STAT) pathway in TNFα-mediated senescence. TNFα initiates a STAT-dependent autocrine loop leading to sustained inflammation, DNA damage, and expression of interferon response genes to lock cells into senescence. Further, we show STAT1/3 activation is necessary for cytokine and ROS production during TNFα-induced senescence. However, inhibition of STAT1/3 did not rescue cells from TNFα-mediated senescence. Rather, blockade of STAT activation accelerated senescence, suppressed genes that control the cell cycle, and modulated TNFα-induced senescence. Our findings suggest a positive feedback mechanism via a STAT pathway that sustains cytokine production and reveal a reciprocal regulatory role of JAK/STAT in TNFα-mediated senescence.
Project description:Cellular senescence is a key cell-fate program that leads to an essentially irreversible proliferative arrest in potentially damaged cells. Cytokine production and signaling play a significant role in senescence. Tumor necrosis factor-alpha (TNFα), an important pro-inflammatory cytokine secreted by some senescent cells, can induce senescence in mouse and human cells. However, downstream signaling pathways and key regulatory genes linking inflammation to senescence are not fully characterized. Using human umbilical vein endothelial cells (HUVECs) as a model, we show TNFα induces permanent growth arrest and increased senescence markers such as p21, p16, and senescence-associated β-galactosidase (SA-β-gal), accompanied by persistent DNA damage and ROS. By gene expression profiling and pathway analysis, we identify the crucial involvement of inflammatory networks, an interferon signature, and persistent activation of the Janus kinase (JAK) /signal transducer and activator of transcription (STAT) pathway in TNFα-mediated senescence. TNFα initiates a STAT-dependent autocrine loop leading to sustained inflammation, DNA damage, and expression of interferon response genes to lock cells into senescence. Further, we show STAT1/3 activation is necessary for cytokine and ROS production during TNFα-induced senescence. However, inhibition of STAT1/3 did not rescue cells from TNFα-mediated senescence. Rather, blockade of STAT activation accelerated senescence, suppressed genes that control the cell cycle, and modulated TNFα-induced senescence. Our findings suggest a positive feedback mechanism via a STAT pathway that sustains cytokine production and reveal a reciprocal regulatory role of JAK/STAT in TNFα-mediated senescence.
Project description:We quantified differential microRNA (miRNA) expression in Human umbilical vein endothelial cells (HUVECs)response to Angiogenin (ANG) treatment.These data were used to determine which miRNAs are altered on ANG in Human umbilical vein endothelial cells.
Project description:We depicted the landscapes of both chromatin accessibility and gene expression to reveal gene regulatory networks in human umbilical vein endothelial cell (HUVEC) senescence and found that chromatin accessibilities are re-distributed during senescence.
Project description:Increasing evidence suggest anti-senescence and geroprotective roles for the glucose-lowering drug metformin. In this framework, the ability of metformin to affect the biogenesis of selected microRNAs (miRNAs) was recently suggested. IsomiRs are distinct variations of miRNA sequences, such as addition or deletion of one or more nucleotides at the 5’ and/or 3’ ends of the canonical miRNA sequence. Since no study has comprehensively assessed the miRNA signatures, including isomiR variants, affected by metformin treatment during cellular senescence, we analysed miRNA and isomiR expression in human umbilical vein endothelial cells (HUVECs) undergoing replicative senescence in presence of metformin.
Project description:In order to identify new markers of vascular cell senescence with potential in vivo implications, primary cultured Human Umbilical Vein Endothelial Cells (HUVECs), were analysed for microRNA (miR) expression.