In situ hybridization of stromelysin mRNA in the synovial biopsies from rheumatoid arthritis

Suppressive Effects of a Chinese Herbal Medicine Qing-Luo-Yin Extract on the Angiogenesis of Collagen-induced Arthritis in Rats

Qing-Luo-Yin (QLY), a traditional Chinese herbal medicine for the treatment of rheumatoid arthritis, is a combination of the extracts of Sophora flavescens Ait., Phellodendron amurense Rupr., Sinomenium acutum Rehd. et Wils. and Dioscorea hypoglauca Palib. The suppressive effect of QLY on the development of angiogenesis was investigated in a rat model of collagen-induced arthritis (CIA). QLY (0.3 g/kg) was orally administered daily for 27 days. Neo-angiogenesis, pannus and cartilage damage, the expression of metalloproteinases (MMP)-3 messenger RNA (mRNA) and the level of the tissue inhibitor of matrix metalloproteinase (TIMP)-1 in the synovium were examined by histology, in situ hybridization and immunohistochemiscal assays, respectively. It was observed that the articular morphological alterations, the over-expression of MMP-3 mRNA and the reduced production of TIMP-1 in CIA rats were significantly ameliorated by QLY. QLY performed about as effectively as tripterygium glycosidorum tablets (0.1 g/kg) extracted from Tripterygium wilfordii Hook. f.. These results indicate that QLY exerts a suppressive effect on the angiogenesis of CIA rats, and suggest that the therapeutic effect of QLY could be due to restoring the balance of MMP-3 and TIMP-1 in rheumatoid synovium.

Interleukin-6 upregulates expression of ADAMTS-4 in fibroblast-like synoviocytes from patients with rheumatoid arthritis

AIM

A disintegrin-like and metalloproteinase with thrombospondin type 1 motif (ADAMTS)-4 and ADAMTS-5 play crucial roles in the cleavage of aggrecan. Several recent studies have demonstrated the effect of cytokines such as interleukin (IL)-1β, tumor necrosis factor-α and transforming growth factor-β on the expression of ADAMTS-4 and ADAMTS-5 in fibroblast-like synoviocytes (FLS). However, the effect of IL-6 remains unclear. The aim of this study is to investigate the expression of ADAMTS-4 and ADAMTS-5 in FLS of rheumatoid arthritis (RA) patients after IL-6 stimulation.

METHOD

Immunohistochemical staining was performed to examine the expression and localization of ADAMTS-4 and ADAMTS-5 in RA synovium. FLS isolated from RA patients were stimulated by IL-6 and soluble IL-6 receptor (sIL-6R) in the presence or absence of anti-IL-6R antibody, and the expression levels of ADAMTS-4 and ADAMTS-5 messenger RNA (mRNA) were assessed using real-time polymerase chain reaction. Furthermore, the IL-6 signaling pathway for regulation of ADAMTS-4 and ADAMTS-5 was also examined.

RESULTS

Staining for ADAMTS-4 and ADAMTS-5 was mainly observed in the sublining layer of synovial membrane and pannus. The expression of ADAMTS-4 mRNA was increased by IL-6/sIL-6R, whereas that of ADAMTS-5 was decreased. Anti-IL-6R antibody suppressed the effect of IL-6/sIL-6R. Mitogen-activated protein kinase (MAPK)/extracellular signal-related kinase (ERK) kinase (MEK)1/2 inhibitor U0126 inhibited the effect of IL-6/sIL-6R on ADAMTS-4 mRNA expression in FLS. Signal transducer and activator of transcription 3 (STAT3) inhibitor parthenolide inhibited the effect of IL-6/sIL-6R on ADAMTS-4, and downregulated ADAMTS-5 expression.

CONCLUSION

These results suggest IL-6 may participate in cartilage destruction in RA as an inducer of ADAMTS-4 expression from FLS.

Endothelial cell phenotypes in the rheumatoid synovium: activated, angiogenic, apoptotic and leaky

Endothelial cells are active participants in chronic inflammatory diseases. These cells undergo phenotypic changes that can be characterised as activated, angiogenic, apoptotic and leaky. In the present review, these phenotypes are described in the context of human rheumatoid arthritis as the disease example. Endothelial cells become activated in rheumatoid arthritis pathophysiology, expressing adhesion molecules and presenting chemokines, leading to leukocyte migration from the blood into the tissue. Endothelial cell permeability increases, leading to oedema formation and swelling of the joints. These cells proliferate as part of the angiogenic response and there is also a net increase in the turnover of endothelial cells since the number of apoptotic endothelial cells increases. The endothelium expresses various cytokines, cytokine receptors and proteases that are involved in angiogenesis, proliferation and tissue degradation. Associated with these mechanisms is a change in the spectrum of genes expressed, some of which are relatively endothelial specific and others are widely expressed by other cells in the synovium. Better knowledge of molecular and functional changes occurring in endothelial cells during chronic inflammation may lead to the development of endothelium-targeted therapies for rheumatoid arthritis and other chronic inflammatory diseases.

Angiogenesis and inflammatory cell infiltration in lumbar disc herniation

STUDY DESIGN

Immunohistochemical study of the angiogenesis and inflammatory cell invasion in lumbar disc herniation. OBJECTIVES To observe the blood vessel formation within the extracellular matrix in lumbar disc herniation, and to elucidate the role of angiogenesis in the natural shrinking of hernias.

SUMMARY OF BACKGROUND DATA

There have been few reports of detailed observation of blood vessel formation within the extracellular matrix, and the role that angiogenesis plays in the natural shrinking of hernias has not been elucidated.

METHODS

Twenty tissue samples surgically removed from 17 patients with herniated discs were studied (9 men, 8 women, 23-58 years old, 11 extrusion type, 9 sequestration type). In the immunohistochemical study, an anti-CD34 antibody for vascular endothelial cells, an anti-CD68 for macrophages, and an anti-vascular endothelial growth factor antibody was used for vascular endothelial growth factor.

RESULTS

Many spindle-shaped cells expressing vascular endothelial growth factor were seen inside granulation tissue infiltrating the cartilage matrix, and the number of vascular endothelial growth factor-positive cells and the number of CD34+ cells were positively correlated (R = 0.73, P < 0.001). In the area surrounding CD34+ cells that had formed a lumen, many CD68+ cells were observed, and the number of CD34+ cells and the number of CD68+ cells were positively correlated (R = 0.66, P < 0.001).

CONCLUSIONS

The results suggest that the vascular endothelial growth factor produced by the spindle-shaped cells acts to promote angiogenesis inside granulation tissue infiltrating the cartilage matrix, and that new blood vessels play an important role as a passage for macrophages into the degenerated matrix.

Type II alveolar epithelial cells and interstitial fibroblasts express connective tissue growth factor in IPF

Connective tissue growth factor (CTGF) is a growth and chemotactic factor for fibroblasts encoded by an immediate early gene that is transcriptionally activated by transforming growth factor-beta. Previous studies have shown that both CTGF messenger ribonuclear acid (mRNA) and protein are expressed in renal fibrosis and bleomycin-induced pulmonary fibrosis in mice. The aim of the present study was to investigate the localization of CTGF protein and its mRNA expression in the fibrotic lung tissue of patients with idiopathic pulmonary fibrosis (IPF). Using human fibrotic lung tissue obtained from eight autopsy cases and four biopsy cases with IPF, immunohistochemical staining, in situ hybridization, and reverse transcription-polymerase chain reaction (RT-PCR) were performed. The cellular immunoreactivity for CTGF was markedly increased in the lung tissue of patients with IPF, compared to normal lungs. The immunolocalization of CTGF was confined predominantly to proliferating type II alveolar epithelial cells and activated fibroblasts. In the normal lung, type II alveolar epithelial cells stained for CTGF were sparsely distributed. CTGF mRNA was localized in proliferating type II alveolar epithelial cells and activated fibroblasts in the interstitium of fibrotic lung tissues. RT-PCR analysis showed that CTGF mRNA was expressed at a higher level in fibrotic lungs than in normal lungs. In both an autocrine and a paracrine manner, type II alveolar epithelial cells and activated fibroblasts may play a critical role in pulmonary fibrosis by producing connective tissue growth factor which modulates fibroblast proliferation and extracellular matrix production.