Paeoniflorin Inhibits Proliferation of Fibroblast-Like Synoviocytes through Suppressing G-Protein-Coupled Receptor Kinase 2

Abstract

Paeoniflorin (Pae) is a monoterpene glucoside and the main component of the total glucosides of paeony (TGP) extracted from the roots of Paeonia lactiflora. Its anti-inflammatory effect is associated with regulating G-protein-coupled receptors (GPCRs) signaling. The aim of this study was to explore the expression change of G-protein-coupled receptor kinase 2 (GRK2) in fibroblast-like synoviocytes (FLS) and the effect of Pae. Pae was obtained and purified from the roots of Paeonia lactiflora. We investigated the expression of GRK2 in synovium during the inflammatory process and assessed the effects of a specific GRK2 inhibitor and Pae on proliferation, cAMP level, and protein kinase A (PKA) activity of FLS in vitro. Additionally, the effect of Pae on GRK2 expression in FLS was detected in vitro. Expression of GRK2 in synovium from CIA rats increased during the inflammatory process. The specific GRK2 inhibitor suppressed proliferation and increased the cAMP level as well as PKA activity of FLS, and Pae had the same effects. Furthermore, Pae decreased GRK2 expression in FLS in vitro. Our results indicate that a chronic inflammatory process in CIA induces upregulation of GRK2 expression in FLS, and Pae can reverse this change, which might be one of the important mechanisms for Pae regulating GPCRs signaling and suppressing the proliferation of FLS in CIA.

Key words

G-protein-coupled receptor kinase 2 - fibroblast-like synoviocytes - collagen-induced arthritis - paeoniflorin - Paeonia lactiflora - Paeoniaceae

References

• 1 Scott D L, Wolfe F, Huizinga T W. Rheumatoid arthritis.  Lancet. 2010;  376 1094-1108
• 2 Brand D D, Kang A H, Rosloniec E F. Immunopathogenesis of collagen arthritis.  Springer Semin Immunopathol. 2003;  25 3-18
• 3 Cho Y G, Cho M L, Min S Y, Kim H Y. Type II collagen autoimmunity in a mouse model of human rheumatoid arthritis.  Autoimmun Rev. 2007;  7 65-70
• 4 Goronzy J J, Weyand C M. Developments in the scientific understanding of rheumatoid arthritis.  Arthritis Res Ther. 2009;  11 249
• 5 Bartok B, Firestein G S. Fibroblast-like synoviocytes: key effector cells in rheumatoid arthritis.  Immunol Rev. 2010;  233 233-255
• 6 Chang S K, Gu Z, Brenner M B. Fibroblast-like synoviocytes in inflammatory arthritis pathology: the emerging role of cadherin-11.  Immunol Rev. 2010;  233 256-266
• 7 Park P S, Filipek S, Wells J W, Palczewski K. Oligomerization of G protein-coupled receptors: past, present, and future.  Biochemistry. 2004;  43 15643-15656
• 8 Chen Q, Wei W. Effects and mechanisms of glucosides of chaenomeles speciosa on collagen-induced arthritis in rats.  Int Immunopharmacol. 2003;  3 593-608
• 9 Xu H M, Wei W, Jia X Y, Chang Y, Zhang L. Effects and mechanisms of total glucosides of paeony on adjuvant arthritis in rats.  J Ethnopharmacol. 2007;  109 442-448
• 10 Chang Y, Wei W, Zhang L, Xu H M. Effects and mechanisms of total glucosides of paeony on synoviocytes activities in rat collagen-induced arthritis.  J Ethnopharmacol. 2009;  121 43-48
• 11 Zhang L L, Wei W, Wang N P, Wang Q T, Chen J Y, Chen Y, Wu H, Hu X Y. Paeoniflorin suppresses inflammatory mediator production and regulates G protein-coupled signaling in fibroblast-like synoviocytes of collagen induced arthritic rats.  Inflamm Res. 2008;  57 388-395
• 12 Kelly E, Bailey C P, Henderson G. Agonist-selective mechanisms of GPCR desensitization.  Br J Pharmacol. 2008;  153 S379-S388
• 13 Lombardi M S, Kavelaars A, Schedlowski M, Bijlsma J W, Okihara K L, Van de Pol M, Ochsmann S, Pawlak C, Schmidt R E, Heijnen C J. Decreased expression and activity of G-protein-coupled receptor kinases in peripheral blood mononuclear cells of patients with rheumatoid arthritis.  FASEB J. 1999;  13 715-725
• 14 Lombardi M S, Kavelaars A, Cobelens P M, Schmidt R E, Schedlowski M, Heijnen C J. Adjuvant arthritis induces down-regulation of G protein-coupled receptor kinases in the immune system.  J Immunol. 2001;  166 1635-1640
• 15 Wu H, Wei W, Song L, Zhang L, Chen Y, Hu X. Paeoniflorin induced immune tolerance of mesenteric lymph node lymphocytes via enhancing beta 2-adrenergic receptor desensitization in rats with adjuvant arthritis.  Int Immunopharmacol. 2007;  7 662-673
• 16 Zhao W, Tong T, Wang L, Li P P, Chang Y, Zhang L L, Wei W. Chicken type II collagen induced immune tolerance of mesenteric lymph node lymphocytes by enhancing beta2-adrenergic receptor desensitization in rats with collagen-induced arthritis.  Int Immunopharmacol. 2011;  11 12-18
• 17 Liu D Z, Xie K Q, Ji X Q, Ye Y, Jiang C L, Zhu X Z. Neuroprotective effect of paeoniflorin on cerebral ischemic rat by activating adenosine A1 receptor in a manner different from its classical agonists.  Br J Pharmacol. 2005;  146 604-611
• 18 Zhu L, Wei W, Zheng Y Q, Jia X Y. Effects and mechanisms of total glucosides of paeony on joint damage in rat collagen-induced arthritis.  Inflamm Res. 2005;  54 211-220
• 19 Zheng Y Q, Wei W. Total glucosides of paeony suppresses adjuvant arthritis in rats and intervenes cytokine-signaling between different types of synoviocytes.  Int Immunopharmacol. 2005;  5 1560-1573
• 20 Premont R T, Gainetdinov R R. Physiological roles of G protein-coupled receptor kinases and arrestins.  Annu Rev Physiol. 2007;  69 511-534
• 21 Ribas C, Penela P, Murga C, Salcedo A, García-Hoz C, Jurado-Pueyo M, Aymerich I, Mayor jr. F. The G protein-coupled receptor kinase (GRK) interactome: role of GRKs in GPCR regulation and signaling.  Biochim Biophys Acta. 2007;  1768 913-922
• 22 Vroon A, Kavelaars A, Limmroth V, Lombardi M S, Goebel M U, Van Dam A M, Caron M G, Schedlowski M, Heijnen C J. G protein-coupled receptor kinase 2 in multiple sclerosis and experimental autoimmune encephalomyelitis.  J Immunol. 2005;  174 4400-4406
• 23 Vroon A, Heijnen C J, Kavelaars A. GRKs and arrestins: regulators of migration and inflammation.  J Leukoc Biol. 2006;  80 1214-1221
• 24 Sánchez-Más J, Guillo L A, Zanna P, Jiménez-Cervantes C, García-Borrón J C. Role of G protein-coupled receptor kinases in the homologous desensitization of the human and mouse melanocortin 1 receptors.  Mol Endocrinol. 2005;  19 1035-1048
• 25 Desai A N, Salim S, Standifer K M, Eikenburg D C. Involvement of G protein-coupled receptor kinase (GRK) 3 and GRK2 in down-regulation of the alpha2B-adrenoceptor.  J Pharmacol Exp Ther. 2006;  317 1027-1035
• 26 Stork P J, Schmitt J M. Crosstalk between cAMP and MAP kinase signaling in the regulation of cell proliferation.  Trends Cell Biol. 2002;  12 258-266
• 27 Dumaz N, Marais R. Integrating signals between cAMP and the RAS/RAF/MEK/ERK signalling pathways.  FEBS J. 2005;  272 3491-3504
• 28 Dumaz N, Marais R. Protein kinase A blocks Raf-1 activity by stimulating 14-3-3 binding and blocking Raf-1 interaction with Ras.  J Biol Chem. 2003;  278 29819-29823
• 29 Jiang D, Chen Y, Hou X, Xu J, Mu X, Chen W. Influence of Paeonia lactiflora roots extract on cAMP-phosphodiesterase activity and related anti-inflammatory action.  J Ethnopharmacol. 2011;  137 914-920
• 30 Wang Q T, Zhang L L, Wu H X, Wei W. The expression change of β-arrestins in fibroblast-like synoviocytes from rats with collagen-induced arthritis and the effect of total glucosides of paeony.  J Ethnopharmacol. 2011;  133 511-516