β2-adrenoceptor signaling reduction is involved in the inflammatory response of fibroblast-like synoviocytes from adjuvant-induced arthritic rats
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To investigate the effects of β-AR signaling on fibroblast-like synoviocytes (FLS) from adjuvant-induced arthritis (AA) rats and the partial mechanisms focused on β-AR desensitization mediated by GRK2 and β-arrestin2.
Animals were divided into a control group and an AA model group, and FLSs were cultured. Arthritis index, histopathology of joints, epinephrine (Epi) and norepinephrine (NE) were detected in vivo. The effect of the β-AR agonist isoprenaline (ISO) and the β2-AR agonist salbutamol on FLS cell viability were detected by CCK8. Cytokines TNF-α, IL-1β, OPG and RANKL were examined by ELISA. The expression of β2-AR was detected by immunofluorescence and flow cytometry. The cytomembrane expression and desensitization of β2-AR, GRK2, and β-arrestin2 were measured by flow cytometry and western blot.
The concentration of NE increased to a peak on day 21, which was consistent with the arthritis index. The levels of Epi and NE in synovial tissues were decreased. ISO inhibited FLS cell viability and TNF-α, IL-1β, and RANKL secretion, and promoted OPG secretion. β2-AR mediated the effects of ISO on FLS cell viability. β2-AR signaling was weaker in AA rats compared to the controls. Elevated GRK2 and β-arrestin2 in cytomembranes promoted β2-AR desensitization and may decrease the anti-inflammatory effect of β2-AR signaling.
The activation of β2-AR signaling exerts its anti-inflammatory activities on FLS. β2-AR signaling decreased in the AA model, which might be related to the increased membrane expression of GRK2 and β-arrestin2, and promoted the excessive desensitization of β2-AR. Decreased β2-AR signaling may be relevant to the exacerbation of arthritis inflammation.
KeywordsFibroblast-like synoviocytes Adjuvant-induced arthritis Adrenoreceptor GRK2 β-arrestin2 Salbutamol
This work was financially supported by the National Nature Science Foundation of China (Nos. 81330081, 81302784, 81302845, 81503084), Key projects of Anhui province university outstanding youth talent fund (gxyqZD2018023), and Grants for Scientific Research of BSKY (No. XJ201428) from Anhui Medical University.
WW contributed to the design of the study, served as the study coordinator, and helped to review the manuscript. HW designed the study, performed experiments, collected data and wrote the manuscript. JC, CW, LL, YZ, AZ, YW, and LZ helped perform experiments and interpret data. All authors read and approved the final manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interest.
- Cahill TJ III, Thomsen ARB, Tarrasch JT, Plouffe B, Nguyen AH, Yang F, Huang L-Y, Kahsai AW, Bassoni DL, Gavino BJ, Lamerdin JE, Triest S, Shukla AK, Berger B, Little J IV, Antar A, Blanc A, Qu C-X, Chen X, Kawakami K, Inoue A, Aoki J, Steyaert J, Sun JP, Bouvier M, Skiniotis G, Robert J (2017) Lefkowitz. Distinct conformations of GPCR–β-arrestin complexes mediate desensitization, signaling, and endocytosis. Proc Natl Acad Sci USA 114:2562–2567CrossRefGoogle Scholar
- Cutolo M, Prete C, Walker J (1999) Is stress a factor in the pathogenesis of autoimmune rheumatic diseases? Clin Exp Rheumatol 17:515–518Google Scholar
- Emori T, Hirose J, Ise K, Yomoda JI, Kasahara M, Shinkuma T, Yoshitomi H, Ito H, Hashimoto M, Sugahara S, Fujita H, Yamamoto N, Morita Y, Narumiya S, Aramori I (2017) Constitutive activation of integrin α9 augments self-directed hyperplastic and proinflammatory properties of fibroblast-like synoviocytes of rheumatoid arthritis. J Immunol 199:3427–3436CrossRefGoogle Scholar
- Mu N, Gu J, Huang T, Zhang C, Shu Z, Li M, Hao Q, Li W, Zhang W, Zhao J, Zhang Y, Huang L, Wang S, Jin X, Xue X, Zhang W, Zhang Y (2016) A novel NF-κB/YY1/microRNA-10a regulatory circuit in fibroblast-like synoviocytes regulates inflammation in rheumatoid arthritis. Sci Rep 6:20059CrossRefGoogle Scholar
- Sato H, Muraoka S, Kusunoki N, Masuoka S, Yamada S, Ogasawara H, Imai T, Akasaka Y, Tochigi N, Takahashi H, Tsuchiya K, Kawai S, Nanki T (2017) Resistin upregulates chemokine production by fibroblast-like synoviocytes from patients with rheumatoid arthritis. Arthritis Res Ther 19:263CrossRefGoogle Scholar