Dataset Information

TNF-?-mediated proliferation of vascular smooth muscle cells involves Raf-1-mediated inactivation of Rb and transcription of E2F1-regulated genes.

ABSTRACT: Atherosclerosis is characterized by hyperplastic neointima and an inflammatory response with cytokines such as TNF?. TNF? is a pleiotropic cytokine that mediates inflammatory, proliferative, cytostatic and cytotoxic effects in a variety of cell types, including endothelial cells and vascular smooth muscle cells (VSMCs). Interestingly, TNF? has been shown to play two very opposing roles in these cell types; it inhibits proliferation and induces apoptosis in endothelial cells, while it enhances the proliferation and migration of VSMCs. Here we show that TNF? is capable of stimulating proliferation of rat VSMCs as well as human VSMCs in a Raf-1/MAP K-dependent manner. TNF? could increase the expression of E2F-regulated proliferative cdc6, Thymidylate synthase (TS) and cdc25A genes in Aortic smooth muscle cells (AoSMC), as seen by real time PCR assays. There is an activation of the stress-induced kinase, JNK1, in VSMCs upon TNF? stimulation. TNF? was capable of inducing binding of the Raf-1 kinase to Rb, and treatment with the Rb-Raf-1 inhibitor, RRD-251, could prevent TNF?-induced S-phase entry in AoSMCs. In addition, inhibition of Raf-1 or Src kinases using pharmacologic inhibitors could also prevent S-phase entry, while inhibition of JNK was not as effective. These results suggest that inhibiting the Rb-Raf-1 interaction is a potential avenue to prevent VSMC proliferation associated with atherosclerosis.

SUBMITTER: Davis R

PROVIDER: S-EPMC3272234 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

TNF-α-mediated proliferation of vascular smooth muscle cells involves Raf-1-mediated inactivation of Rb and transcription of E2F1-regulated genes.

Davis Rebecca R Pillai Smitha S Lawrence Nicholas N Sebti Said S Chellappan Srikumar P SP

Cell cycle (Georgetown, Tex.) 20120101 1

Atherosclerosis is characterized by hyperplastic neointima and an inflammatory response with cytokines such as TNFα. TNFα is a pleiotropic cytokine that mediates inflammatory, proliferative, cytostatic and cytotoxic effects in a variety of cell types, including endothelial cells and vascular smooth muscle cells (VSMCs). Interestingly, TNFα has been shown to play two very opposing roles in these cell types; it inhibits proliferation and induces apoptosis in endothelial cells, while it enhances th ...[more]

PMID: 22185776

Similar Datasets

Project description:BackgroundVascular remodelling is an essential pathophysiological state in many circulatory diseases. Abnormal vascular smooth muscle cell (VSMC) behaviour leads to neointimal formation and may eventually results in major adverse cardiovascular events. The C1q/TNF-related protein (C1QTNF) family is closely associated with cardiovascular disease. Notably, C1QTNF4 has unique two C1q domains. However, the role of C1QTNF4 in vascular diseases remains unclear.MethodsC1QTNF4 expression was detected in human serum and artery tissues using ELISA and multiplex immunofluorescence (mIF) staining. Scratch assay, transwell assay and confocal microscopy were used to investigate C1QTNF4 effects on VSMC migration. EdU incorporation, MTT assay and cell counting experiment revealed C1QTNF4 effects on VSMC proliferation. C1QTNF4-transgenic, C1QTNF4-/- and AAV9-mediated VSMC-specific C1QTNF4 restoration C1QTNF4-/- mouse and rat disease models were generated. RNA-seq, quantitative real-time PCR, western blot, mIF, proliferation and migration assays were used to investigate the phenotypic characteristics and underlying mechanisms.ResultsSerum C1QTNF4 levels were decreased in patients with arterial stenosis. C1QTNF4 shows colocalisation with VSMC in human renal arteries. In vitro, C1QTNF4 inhibits VSMC proliferation and migration and alters VSMC phenotype. In vivo, an adenovirus-infected rat balloon injury model, C1QTNF4-transgenic and C1QTNF4-/- mouse wire-injury models with or without VSMC-specific C1QTNF4 restoration were established to mimic the VSMC repair and remodelling. The results show that C1QTNF4 decreases intimal hyperplasia. Especially, we displayed the rescue effect of C1QTNF4 in vascular remodelling using AAV vectors. Next, transcriptome analysis of artery tissue identified the potential mechanism. In vitro and in vivo experiments confirm that C1QTNF4 ameliorates neointimal formation and maintains vascular morphology by downregulating the FAK/PI3K/AKT pathway.ConclusionsOur study demonstrated that C1QTNF4 is a novel inhibitor of VSMC proliferation and migration that acts by downregulating the FAK/PI3K/AKT pathway, thus protecting blood vessels from abnormal neointima formation. These results provide new insights into promising potent treatments for vascular stenosis diseases.

Dataset Information

TNF-?-mediated proliferation of vascular smooth muscle cells involves Raf-1-mediated inactivation of Rb and transcription of E2F1-regulated genes.

Publications

TNF-α-mediated proliferation of vascular smooth muscle cells involves Raf-1-mediated inactivation of Rb and transcription of E2F1-regulated genes.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets