Inhibition of CCR1/CCR5 mediated angiogenesis and joint destruction by EGCG

描述(由申请人提供)： 类风湿性关节炎(RA)是一种慢性炎症性关节疾病，激活的滑膜成纤维细胞产生趋化因子，通过释放基质降解酶促进关节软骨和下层骨的侵袭。重要的是，RANTES/CCL5和巨噬细胞炎症蛋白(MIP-11)/CCL3是在疾病发生时激活CCR1和CCR5受体以吸引T细胞和单核细胞进入关节的趋化因子。因此，调节CCR1/CCR5受体的表达成为治疗类风湿关节炎的新策略。在我们的初步发现中，表没食子儿茶素没食子酸酯(EGCG)是一种有效的抗炎分子，它可以抑制白细胞介素12(IL-12)诱导的RA滑膜成纤维细胞产生RANTES/CCL5和MIP-11/CCL3)，这是通过CCR1/CCR5受体介导的。EGCG还抑制IL-12诱导的人RA滑膜成纤维细胞的软骨和骨破坏标志物(IL-6、VEGF和PGE2)以及基质降解酶基质金属蛋白酶-2(MMP2)的活性。[一项体内研究表明，EGCG可以预防大鼠佐剂性关节炎(AIA)。]这项提议充分利用了这些新颖的观察结果。这项工作的中心假设是，EGCG通过阻断CCR1/CCR5受体的表达，抑制大鼠佐剂性关节炎(AIA)模型和RA滑膜组织(ST)-严重联合免疫缺陷(SCID)嵌合体的细胞募集、血管生成和关节破坏。在目的1中，我们将测试EGCG是否抑制CCR1/CCR5受体的表达，从而抑制RANTES/CCL5或MIP-11/CCL3的活性和RA ST外植体的血管生成。在目标2中，我们将研究EGCG是否能阻止CCR1/CCR5受体在人RA ST严重联合免疫缺陷(SCID)小鼠嵌合体中介导的细胞募集和组织侵袭。最后，在目标3中，我们将确定EGCG是否下调CCR1/CCR5受体的表达，以抑制RA大鼠AIA模型的血管生成、软骨和骨破坏。拟议实验的成功可能会导致EGCG作为RA和可能的其他自身免疫性疾病的潜在治疗选择的发展取得重大进展。项目简介类风湿性关节炎(RA)是一种慢性炎症性关节疾病，是与工作相关的残疾的主要原因，也是由于昂贵但不完整的传统疗法而带来的重大社会经济健康挑战。利用人类类风湿关节炎动物模型，我们建议测试表没食子儿茶素没食子酸酯(EGCG)--绿茶中发现的一种潜在的抗炎分子--在抑制类风湿关节炎软骨和骨的破坏方面的效果。拟议实验的成功可能导致EGCG作为一种潜在的安全和廉价的类风湿关节炎治疗选择的发展取得重大进展。

DESCRIPTION (provided by applicant): PROJECT SUMMARY Rheumatoid arthritis (RA) is a chronic inflammatory joint disorder in which activated synovial fibroblasts produce chemokines that facilitate the invasion of the articular cartilage and underlying bone by the release of matrix-degrading enzymes. Importantly, RANTES/CCL5 and macrophage inflammatory protein (MIP-11)/CCL3 are the chemokines shown to activate CCR1 and CCR5 receptor to attract T cells and monocytes into joints during the onset of disease. Thus, regulation of CCR1/CCR5 receptor expression is emerging as a novel therapeutic strategy for RA. In our preliminary findings, epigallocatechin-3-gallate (EGCG), a potent anti-inflammatory molecule, blocked interleukin-12 (IL-12)-induced RANTES/CCL5 and MIP-11/CCL3 ) production in RA synovial fibroblasts that are mediated via CCR1/CCR5 receptors. EGCG also inhibited IL-12-induced markers of cartilage and bone destruction (IL-6, VEGF, and PGE2), and matrix degrading enzyme matrix metalloproteinase-2 (MMP-2) activity in human RA synovial fibroblasts. [An in vivo study showed that EGCG prevented adjuvant-induced arthritis (AIA) in rats.] This proposal capitalizes on these novel observations. The central hypothesis of the work proposed is that EGCG inhibits cell recruitment, angiogenesis and joint destruction in rat adjuvant-induced arthritis (AIA) model and in RA synovial tissue (ST)-severe combined immunodeficient (SCID) chimera by blocking CCR1/CCR5 receptor expression. In Aim 1, we will test whether EGCG inhibits CCR1/CCR5 receptor expression to suppress RANTES/CCL5 or MIP-11/CCL3 activity and angiogenesis in RA ST explants. In Aim 2, we will study if EGCG blocks CCR1/CCR5 receptor mediated cell recruitment and tissue invasion in a human RA ST- severe combined immunodeficiency (SCID) mouse chimera. Finally, in Aim 3, we will determine whether EGCG downregulates CCR1/CCR5 receptor expression to inhibit angiogenesis, and cartilage and bone destruction in a rat AIA model of RA. The success of the proposed experiments may lead to a significant advancement in the development of EGCG as a potential treatment option for RA and possibly other autoimmune diseases. PROJECT NARRATIVE Rheumatoid arthritis (RA), a chronic inflammatory joint disorder, is a leading cause of work-related disabilities and a significant socio-economic health challenge due to expensive, yet incomplete, conventional therapies. Using animal models of human RA, we propose to test the efficacy of epigallocatechin-3-gallate (EGCG), a potential anti-inflammatory molecule found in green tea, in inhibiting the destruction of the cartilage and bone in RA. The success of the proposed experiments may lead to a significant advancement in the development of EGCG as a potentially safe and inexpensive treatment option for RA.