Correlation between plasma contents of tumor necrosis factor-alpha and expressions of vascular endothelium growth factor of synovium in collagen-induced arthritis rats / 中国组织工程研究

ABSTRACT

BACKGROUND: Pathological change of synovium in rheumatoid arthritis (RA) has the characteristic of tumor-like growth, it appears thickening of the synovium tissue and the formatiom of pannus, which generate periarticular erosion and destruction. Multiplicate cell factors and growth factors participate in the development course of tumor-like lesion of synovium, and the tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor(VEGF)play important roles in the development of RA and the formation of pannus.OBJECTIVE: To observe the contents of plasma TNF-α of collagen-induced arthritis and the expression change of VEGF of synovium at different time point, and investigate the effect and correlation of TNF-α and VEGF in the pathogenesis of RA.DESIGN: Randomized grouping experiment taking animals as subjects.SETTING: Institute integrated traditional and western medicine of Xiangya Hospital of Central South University.MATERIALS The experiment was finished from July to November 2003 in the laboratory of institute integrated traditional and western medicine.Forty SD rats aged 45-50 days were selected, the rats were randomly divided into the normal control group (n=10) and collagen-induced arthritis model group(n=30).METHODS: 10 mg Cattle collagen type Ⅱ and 5 ml full Freund adjuvant were grinded together, 100 μL of which were intradermally injected at the root of tails of rats, collagen-induced arthritis model of rats were re-immunized with the above-mentioned methòd and dosage after 21 days. The accumulated points of arthritis index was evaluated based on degree and extent of flare and the condition of tumefaction and deformation, the higher the accumulated points of arthritis index were, the more serious the arthritis symptom was. The blood was obtained by decapitation after 25 days in normal control group, and in the collagen-induced arthritis model group the blood was obtained by decapitation 25,30,35,40,45 days after immunization (model establishing), the contents of plasma TNF-α of collagen-induced arthritis rats at different time point was detected by radio-immune assay, the level of expression of VEGF in synovium tissue were detected with immunohistochemical method simultaneously, the correlation of invasion time and the neovascularization of synovium. The accumulated points of arthritis index . TNF-α and VEGF was observed. The correlation of TNF-α and VEGF was analyzed with the linear correlation analysis, the correlation of the accumulated points of arthritis index and TNF-α. VEGF was analyzed with the rank correlation analysis.MAIN OUTCOME MEASURES: The correlation of invasion time of collagen-induced arthritis with the accumulated points of arthritis index, with the plasma content of TNF-α and the expression of VEGF, the correlation analysis of the plasma content of TNF-α of collagen- induced arthritis rats with the expression of VEGF in synovium.RESULTS: Forty rats attended the experiment, all of them entered the final analysis. the neovascularization of synovium was increased, synovium was thickening, the accumulated points of arthritis index was gradually increased, and the contents of TNF-α and level of VEGF were increased accordingly with the process of the invasion time of the collagen-induced arthritis rats; Its accumulated points of arthritis index had the positive correlation with the level of expression of VEGF (r=0.535 ,P ＜ 0.05)and had the correlated increasing tendency with the contents of TNF-α, but there was no significant difference(r=0.371 ,P ＞ 0.05 ). the plasma contents of TNF-α had the positive correlation with the level of expressions of VEGF (r=0.893,P ＜ 0.01 ).CONCLUSION: The TNF-α and VEGF have an important effect on the inflammatory reaction of RA and Cytokine network of neovascularization of synovium, they are possibly mutually influenced and promoted and have the effect of mediating the malignant network circulation; They are the key factors among multiplicate ones which mediate the generation and development of RA, bone erosion and Mutilation.