Hashiramoto Akira, Sakai China, Yoshida Kohsuke, Tsumiyama Ken, Miura Yasushi, Shiozawa Kazuko, Nose Masato, Komai Koichiro, Shiozawa Shunichi
Kobe University FHS School of Medicine, Kobe University Hospital, Sumaku, Kobe, Japan.
Arthritis Rheum. 2007 Jul;56(7):2170-9. doi: 10.1002/art.22727.
To determine whether angiopoietin 1 (Ang-1) potentiates overgrowth of the synovium and joint degradation in rheumatoid arthritis (RA), and to clarify the cell-signaling mechanisms of Ang-1 in the rheumatoid joint.
Expression of Ang-1, TIE-2 (a receptor for Ang-1), and matrix metalloproteinase 3 (MMP-3) was studied by immunohistochemistry. Activation of the ERK/MAPK and phosphatidylinositol (PI) 3-kinase/Akt pathways and of NF-kappaB was determined by Western blotting and an NF-kappaB p65 DNA binding activity assay, respectively. Induction of apoptosis was evaluated by nuclear staining, cell viability assay, and Western blotting of caspases. Synovial cell migration was evaluated by actin polymerization, Western blotting of Rho family proteins, and affinity purification with Rhotekin-Rho and p21-activated kinase 1. Matrix degradation was examined by induction of proMMP-3 secretion from synovial cells followed by in vitro cartilaginous matrix degradation assay.
Ang-1 stimulated the ERK/MAPK and PI 3-kinase/Akt pathways in a cooperative but independent manner, which enhanced rheumatoid synovium overgrowth and joint destruction. In addition, Ang-1 activated NF-kappaB via Akt to promote cell growth, but also inhibited cell apoptosis via ERK and Akt. Ang-1 directly potentiated the extension of synovial cells in an ERK- and Akt-dependent manner by up-regulating Rho family proteins, which attenuated Rac signaling and led to membrane ruffling. Ang-1 induced proMMP-3 secretion from synovial cells, which resulted in direct degradation of the cartilaginous matrix.
Ang-1 stimulates the ERK/MAPK and PI 3-kinase/Akt pathways cooperatively, but in a manner independent of each other, to directly potentiate synovium overgrowth and joint destruction in RA. In addition to inflammatory cytokines, Ang-1/TIE-2 signaling appears to be an independent factor that contributes to the destruction of the rheumatoid joint.
确定血管生成素1（Ang-1）是否会增强类风湿关节炎（RA）中滑膜的过度生长和关节破坏，并阐明Ang-1在类风湿关节中的细胞信号传导机制。
通过免疫组织化学研究Ang-1、TIE-2（Ang-1的一种受体）和基质金属蛋白酶3（MMP-3）的表达。分别通过蛋白质印迹法和NF-κB p65 DNA结合活性测定法确定ERK/MAPK和磷脂酰肌醇（PI）3-激酶/Akt途径以及NF-κB的激活情况。通过核染色、细胞活力测定和半胱天冬酶的蛋白质印迹法评估细胞凋亡的诱导情况。通过肌动蛋白聚合、Rho家族蛋白的蛋白质印迹法以及用Rhotekin-Rho和p21激活激酶1进行亲和纯化来评估滑膜细胞迁移。通过诱导滑膜细胞分泌前MMP-3，随后进行体外软骨基质降解测定来检查基质降解情况。
Ang-1以协同但独立的方式刺激ERK/MAPK和PI 3-激酶/Akt途径，这增强了类风湿滑膜的过度生长和关节破坏。此外，Ang-1通过Akt激活NF-κB以促进细胞生长，但也通过ERK和Akt抑制细胞凋亡。Ang-1通过上调Rho家族蛋白以ERK和Akt依赖的方式直接增强滑膜细胞的伸展，这减弱了Rac信号传导并导致膜褶皱。Ang-1诱导滑膜细胞分泌前MMP-3，这导致软骨基质的直接降解。
Ang-1协同刺激ERK/MAPK和PI 3-激酶/Akt途径，但方式相互独立，以直接增强RA中滑膜的过度生长和关节破坏。除炎症细胞因子外，Ang-1/TIE-2信号似乎是导致类风湿关节破坏的一个独立因素。
