Project description:Arterial smooth muscle cells (ASMCs) undergo phenotypic changes during development and pathological processes in vivo and during cell culture in vitro. Our previous studies demonstrated that retrovirally-mediated expression of the versican V3 splice variant (V3) that lacks glycosaminoglycan chains by ASMCs retards cell proliferation and migration in vitro and reduces neointimal thickening, macrophage and lipid accumulation in animal models of vascular injury and atherosclerosis. However, the molecular pathways induced by V3 expression that are responsible for these changes are not yet clear. In the present study, we employed a microarray approach to examine how expression of V3 induced changes in gene expression and the molecular pathways in ASMCs. We found that forced expression of V3 by ASMCs affected expression of 521 genes by more than 1.5 fold. Gene ontology (GO) analysis shows that components of extracellular matrix were the most significantly affected by V3 expression, indicating that V3 expression elicits profound remodeling of extracellular matrix. In addition, genes regulating the formation of the cytoskeleton which also serve as markers of contractile smooth muscle cells were significantly upregulated. On the other hand, components of the complement system, chemokines, chemokine receptors, and transcription factors crucial for regulating inflammatory processes were among the genes most downregulated. Consistently, we found that the level of myocardin, a key transcription factor promoting contractile ASMC phenotype, was greatly increased while proinflammatory transcription factors NFkappaB1 and C/EBPβ were significantly attenuated in V3-expressing SMCs. Such results indicate that V3 expression reprograms ASMC into differentiated and anti-inflammatory phenotypes. Overall, these findings demonstrate that expression of V3 reprograms ASMCs promoting anti-inflammatory and differentiated smooth muscle cell phenotypes potentially by altering cell-ECM interaction and focal adhesion signaling pathways. Fischer rat ASMCs were transduced with either a retroviral vector expressing the Versican V3 splice variant (LV3SN) or an empty control vector (LXSN) in three independent experiments. In the first experiment, V3 and control transductions were performed with four technical replicates. In the subsequent two experiments, individual transductions were done for the V3 or control treatments. For data analysis, the technical replicates from the first experiment were averaged, and then data from the three experiments was evaluated in a paired manner.
Project description:Arterial smooth muscle cells (ASMCs) undergo phenotypic changes during development and pathological processes in vivo and during cell culture in vitro. Our previous studies demonstrated that retrovirally-mediated expression of the versican V3 splice variant (V3) that lacks glycosaminoglycan chains by ASMCs retards cell proliferation and migration in vitro and reduces neointimal thickening, macrophage and lipid accumulation in animal models of vascular injury and atherosclerosis. However, the molecular pathways induced by V3 expression that are responsible for these changes are not yet clear. In the present study, we employed a microarray approach to examine how expression of V3 induced changes in gene expression and the molecular pathways in ASMCs. We found that forced expression of V3 by ASMCs affected expression of 521 genes by more than 1.5 fold. Gene ontology (GO) analysis shows that components of extracellular matrix were the most significantly affected by V3 expression, indicating that V3 expression elicits profound remodeling of extracellular matrix. In addition, genes regulating the formation of the cytoskeleton which also serve as markers of contractile smooth muscle cells were significantly upregulated. On the other hand, components of the complement system, chemokines, chemokine receptors, and transcription factors crucial for regulating inflammatory processes were among the genes most downregulated. Consistently, we found that the level of myocardin, a key transcription factor promoting contractile ASMC phenotype, was greatly increased while proinflammatory transcription factors NFkappaB1 and C/EBPβ were significantly attenuated in V3-expressing SMCs. Such results indicate that V3 expression reprograms ASMC into differentiated and anti-inflammatory phenotypes. Overall, these findings demonstrate that expression of V3 reprograms ASMCs promoting anti-inflammatory and differentiated smooth muscle cell phenotypes potentially by altering cell-ECM interaction and focal adhesion signaling pathways.
Project description:Knee osteoarthritis (KOA), as a degenerative multifactorial disease, affects the quality of life and mental health of patients, and also brings a huge socioeconomic burden. Treating synovitis have shown promise as anti-inflammatory therapeutics in mitigating OA symptoms and disease progression. Here, by analysing synovial single-cell sequencing (scRNA-seq) data from KOA, we found that synovial fibroblasts (FLS) in OA synovium showed a distinct pro-inflammatory phenotype. We collected synovial tissue from patients with clinical OA as well as from healthy donors, and histological examination was consistent with findings in scRNA-seq. Inspired by recent cross-tissue fibroblast lineage studies, we identified by sequencing that healthy FLS in synovial tissues share transcriptome-level similarities with dermal fibroblasts (DFb). Subsequently, we revealed the local as well as systemic distribution of intra-articular injected DFbs by constructing/extracting two types of rat fibroblasts (luciferase DFbs as well as GFP DFbs). The results demonstrate that DFbs can be locally retained in the synovium for up to three weeks following targeted engrafting on it. And intra-articular injection does not result in DFbs migration to vital organs or the occurrence of histological changes in these organs. A rat model of KOA was constructed by anterior cruciate ligament transection (ACLT) in order to study the therapeutic effect of DFbs on KOA. After injection, the rats showed improvement in painful gait. In addition, histological as well as imaging results showed reduced synovitis and improvement in articular cartilage. Finally we verified the protective effect of DFbs on cytokine-stimulated chondrocytes in a co-culture system.
Project description:Knee osteoarthritis (KOA), as a degenerative multifactorial disease, affects the quality of life and mental health of patients, and also brings a huge socioeconomic burden. Treating synovitis have shown promise as anti-inflammatory therapeutics in mitigating OA symptoms and disease progression. Here, by analysing synovial single-cell sequencing (scRNA-seq) data from KOA, we found that synovial fibroblasts (FLS) in OA synovium showed a distinct pro-inflammatory phenotype. We collected synovial tissue from patients with clinical OA as well as from healthy donors, and histological examination was consistent with findings in scRNA-seq. Inspired by recent cross-tissue fibroblast lineage studies, we identified by sequencing that healthy FLS in synovial tissues share transcriptome-level similarities with dermal fibroblasts (DFb). Subsequently, we revealed the local as well as systemic distribution of intra-articular injected DFbs by constructing/extracting two types of rat fibroblasts (luciferase DFbs as well as GFP DFbs). The results demonstrate that DFbs can be locally retained in the synovium for up to three weeks following targeted engrafting on it. And intra-articular injection does not result in DFbs migration to vital organs or the occurrence of histological changes in these organs. A rat model of KOA was constructed by anterior cruciate ligament transection (ACLT) in order to study the therapeutic effect of DFbs on KOA. After injection, the rats showed improvement in painful gait. In addition, histological as well as imaging results showed reduced synovitis and improvement in articular cartilage. Finally we verified the protective effect of DFbs on cytokine-stimulated chondrocytes in a co-culture system.
Project description:Gene expression patterns following unilateral traumatic brain injury reveals a local pro-inflammatory and remote anti-inflammatory response