1. Geniposide downregulates the <scp>VEGF</scp> / <scp>SphK1</scp> / <scp>S1P</scp> pathway and alleviates angiogenesis in rheumatoid arthritis in vivo and in vitro
- Author
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Yanhong Bu, Meng-die Wang, Hong Wu, Ran Deng, Xue-jing Dai, Heng Zhang, Ming-hui Sun, Yan Wang, and Rong-hui Wang
- Subjects
Vascular Endothelial Growth Factor A ,Small interfering RNA ,Angiogenesis ,Arthritis, Rheumatoid ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,In vivo ,Humans ,Iridoids ,Secretion ,Sphingosine-1-Phosphate Receptors ,Cells, Cultured ,Adaptor Proteins, Signal Transducing ,Cell Proliferation ,Pharmacology ,Tube formation ,0303 health sciences ,Neovascularization, Pathologic ,Chemistry ,Synovial Membrane ,030302 biochemistry & molecular biology ,Endothelial Cells ,Fibroblasts ,In vitro ,030220 oncology & carcinogenesis ,Cancer research ,Tumor necrosis factor alpha ,Signal Transduction - Abstract
The VEGF/SphK1/S1P pathway is closely related to angiogenesis in rheumatoid arthritis (RA), but the precise underlying mechanisms are unclear at present. Here, we explored the involvement of the VEGF/SphK1/S1P cascade in RA models and determined the effects of GE intervention. Our results showed abnormal expression of proteins related to this pathway in RA synovial tissue. Treatment with GE effectively regulated the signal axis, inhibited angiogenesis, and alleviated RA symptoms. In vitro, TNF-ɑ enhanced the VEGF/SphK1/S1P pathway in a co-culture model of fibroblast-like synoviocytes (FLS) and vascular endothelial cells (VEC). GE induced downregulation of VEGF in FLS, restored the dynamic balance of pro-/antiangiogenic factors, and suppressed SphK1/S1P signaling in VEC, resulting in lower proliferation activity, migration ability, tube formation ability, and S1P secretion ability of VEC cells. Additionally, SphK1-specific small interfering RNA (siRNA) blocked the VEGF/SphK1/S1P cascade, which can effectively alleviate the stimulatory effect of FLS on VEC and further enhanced the therapeutic effect of GE. Taken together, our results demonstrate that GE suppresses the VEGF/SphK1/S1P pathway and alleviates the stimulation of VEC by FLS, thereby preventing angiogenesis and promoting therapeutic effects against RA.
- Published
- 2021