IL-6-accelerated calcification by induction of ROR2 in human adipose tissue-derived mesenchymal stem cells is STAT3 dependent. (4th March 2014)

• Record Type: Journal Article
• Authors: Fukuyo, Shunsuke; Yamaoka, Kunihiro; Sonomoto, Koshiro; Oshita, Koichi; Okada, Yosuke; Saito, Kazuyoshi; Yoshida, Yasuhiro; Kanazawa, Tamotsu; Minami, Yasuhiro; Tanaka, Yoshiya
• Is Part Of: Rheumatology. Volume 53:Number 7(2014:Jul.)
• Page Start: 1282
• Page End: 1290
• Publication Date: 2014-03-04
• Subjects: IL-6 -- ROR2 -- ADSCs -- STAT3 -- WNT5A -- ectopic calcification; Rheumatism -- Periodicals; Rheumatology -- Periodicals; 616.723005
• DOI: 10.1093/rheumatology/ket496
• Languages: English
• ISSNs: 1462-0324

Abstract

Abstract : Objective. The mechanisms of ectopic calcification in inflammatory diseases are poorly understood. We investigated the effects of inflammatory cytokines on the mechanisms of calcification in human adipose tissue-derived mesenchymal stem cells (hADSCs). Methods. The effects of inflammatory cytokines were evaluated using hADSCs cultured in osteoblast induction medium. mRNA expression was measured by real-time PCR and protein levels were measured by western blotting. Cell mineralization was evaluated by Alizarin Red S staining. Results. In hADSCs, administration of IL-6/soluble IL-6 receptor (sIL-6R), TNF or IL-1β accelerated calcification through enhanced expression of an osteoblast differentiation marker, runt-related transcription factor 2 ( RUNX2 ). IL-6/sIL-6R had the greatest effect. The transcription of mRNA for receptor tyrosine kinase-like orphan receptor 2 ( ROR2 ), involved in the non-canonical wingless-type (WNT) MMTV integration site pathway, was increased, while β-catenin expression, an essential factor in the canonical WNT signalling pathway for osteoblast differentiation, did not change. Suppression of signal transducer and activator of transcription 3 (STAT3), but not STAT1, by small interfering RNA (siRNA) exerted a strong inhibitory effect on RUNX2 and ROR2 expression, and inhibited accelerated calcification. Conclusion. IL-6/sIL-6R stimulation accelerated the ROR2/WNT5A pathway in hADSCs in a STAT3-dependent manner, resulting in augmented calcification. These results suggest that the mechanisms of ectopic calcification accelerated by IL-6 in hADSCs may be involved in chronic inflammatory tissues and that IL-6 inhibitors may be beneficial in the treatment of ectopic calcification in inflammatory diseases.