First Author | Uchida K | Year | 2015 |
Journal | Clin Exp Immunol | Volume | 180 |
Issue | 3 | Pages | 551-9 |
PubMed ID | 25693634 | Mgi Jnum | J:272214 |
Mgi Id | MGI:6200864 | Doi | 10.1111/cei.12607 |
Citation | Uchida K, et al. (2015) CD11c(+) macrophages and levels of TNF-alpha and MMP-3 are increased in synovial and adipose tissues of osteoarthritic mice with hyperlipidaemia. Clin Exp Immunol 180(3):551-9 |
abstractText | To understand more clearly the link between osteoarthritis and hyperlipidaemia, we investigated the inflammatory macrophage subsets and macrophage-regulated matrix metalloprotease-3 (MMP-3) and A disintegrin and metalloprotease with thrombospondin motifs-4 (ADAMTS4) in synovial (ST) and adipose tissues (AT) of osteoarthritic mice with hyperlipidaemia (STR/Ort). CD11c(+) F4/80(+) CD11b(+) macrophage populations in the ST and AT of 9-month-old STR/Ort and C57BL/6J mice were characterized and compared by flow cytometry and real-time polymerase chain reaction (PCR) analyses. Expression of tumour necrosis factor (TNF)-alpha, MMP-3 and ADAMTS4, and the response of these factors to anionic liposomal clodronate induced-macrophage depletion were also evaluated by real-time PCR. Expression of TNF-alpha in CD11c(+) cells, which were isolated by magnetic beads, was compared to CD11c(-) cells. In addition, the effect of TNF-alpha on cultured synovial fibroblasts and adipocytes was investigated. CD11c(+) F4/80(+) CD11b(+) macrophages were increased in ST and AT of STR/Ort mice. The CD11c(+) cell fraction highly expressed TNF-alpha. Expression of TNF-alpha and MMP3 was increased in ST and AT, and was decreased upon macrophage depletion. TNF-alpha treatment of cultured synovial fibroblasts and adipocytes markedly up-regulated MMP-3. CD11c(+) F4/80(+) CD11b(+) macrophages were identified as a common inflammatory subset in the AT and ST of STR/Ort mice with hyperlipidaemia. The induction of inflammation in AT and ST may be part of a common mechanism that regulates MMP3 expression through TNF-alpha. Our findings suggest that increased numbers of CD11c(+) macrophages and elevated levels of TNF-alpha and MMP-3 in AT and ST may explain the relationship between hyperlipidaemia and OA. |