Interleukin-21 induces migration and invasion of fibroblast-like synoviocytes from patients with rheumatoid arthritis

Propofol inhibits cell proliferation and invasion in rheumatoid arthritis fibroblast-like synoviocytes via the nuclear factor-κB pathway

Propofol is an anesthetic drug commonly used in the clinical practice. The aim of this study is to explore the effect of propofol on the aggressive behaviors of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs). Propofol treatment for 48 or 72 h significantly inhibited the viability of RA-FLSs, but a 24-h treatment did not produce cytotoxic effects. Propofol exposure for 48 h led to reduction of proliferation and induction of apoptosis in RA-FLSs, which was coupled with increased Bax and decreased Bcl-2 and survivin levels. Additionally, treatment with propofol for 24 h significantly suppressed the migration and invasion of RA-FLSs. Mechanistically, propofol inhibited nuclear factor-κB (NF-κB) activity. Overexpression of constitutively active NF-κB p65 reversed the inhibitory effects of propofol on RA-FLSs. Taken together, propofol exerts anti-proliferative and anti-invasive effects on RA-FLSs via the NF-κB pathway and may have therapeutic potential in treatment of RA.

Synovial cellular and molecular markers in rheumatoid arthritis

The profound alterations in the structure, cellular composition, and function of synovial tissue in rheumatoid arthritis (RA) are the basis for the persistent inflammation and cumulative joint destruction that are hallmarks of this disease. In RA, the synovium develops characteristics of a tertiary lymphoid organ, with extensive infiltration of lymphocytes and myeloid cells. Concurrently, the fibroblast-like synoviocytes undergo massive hyperplasia and acquire a tissue-invasive phenotype. In this review, we summarize key components of these processes, focusing on recently-described roles of selected molecular markers of these cellular components of RA synovitis.

IL-21 promotes myocardial ischaemia/reperfusion injury through the modulation of neutrophil infiltration

BACKGROUND AND PURPOSE

The immune system plays an important role in driving the acute inflammatory response following myocardial ischaemia/reperfusion injury (MIRI). IL-21 is a pleiotropic cytokine with multiple immunomodulatory effects, but its role in MIRI is not known.

EXPERIMENTAL APPROACH

Myocardial injury, neutrophil infiltration and the expression of neutrophil chemokines KC (CXCL1) and MIP-2 (CXCL2) were studied in a mouse model of MIRI. Effects of IL-21 on the expression of KC and MIP-2 in neonatal mouse cardiomyocytes (CMs) and cardiac fibroblasts (CFs) were determined by real-time PCR and ELISA. The signalling mechanisms underlying these effects were explored by western blot analysis.

KEY RESULTS

IL-21 was elevated within the acute phase of murine MIRI. Neutralization of IL-21 attenuated myocardial injury, as illustrated by reduced infarct size, decreased cardiac troponin T levels and improved cardiac function, whereas exogenous IL-21 administration exerted opposite effects. IL-21 increased the infiltration of neutrophils and increased the expression of KC and MIP-2 in myocardial tissue following MIRI. Moreover, neutrophil depletion attenuated the IL-21-induced myocardial injury. Mechanistically, IL-21 increased the production of KC and MIP-2 in neonatal CMs and CFs, and enhanced neutrophil migration, as revealed by the migration assay. Furthermore, we demonstrated that this IL-21-mediated increase in chemokine expression involved the activation of Akt/NF-κB signalling in CMs and p38 MAPK/NF-κB signalling in CFs.

CONCLUSIONS AND IMPLICATIONS

Our data provide novel evidence that IL-21 plays a pathogenic role in MIRI, most likely by promoting cardiac neutrophil infiltration. Therefore, targeting IL-21 may have therapeutic potential as a treatment for MIRI.

LINKED ARTICLES

This article is part of a themed section on Spotlight on Small Molecules in Cardiovascular Diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.8/issuetoc.