Increased concentrations of the circulating angiogenesis inhibitor endostatin in patients with systemic sclerosis

Objective. Endostatin is an angiogenesis inhibitor derived from type XVIII collagen. The aim of this study was to determine the concentrations of circ ulating endostatin in patients with systemic sclerosis (SSc), and to assess the relationship between these concentrations, extension of tissular scler osis, and presence of cutaneous scars or ulcers. Methods. The study involved 50 patients with SSc and 30 healthy subjects. C utaneous extension of sclerosis was graded according to Barnett's classific ation system: 33 patients had grade I SSc and 17 patients had grades II or III SSc. The results of pulmonary function tests were abnormal in 31 of 50 patients, 8 of whom also had abnormalities on chest radiograms. Cutaneous s cars or ulcers were found in 22 of 50 patients. Endostatin concentrations w ere determined using a competitive enzyme immunoassay method. Results. The mean circulating endostatin concentration was significantly hi gher in the SSc group than in the healthy subjects group (mean +/- SD 53.2 +/- 22.4 ng/ml versus 9.9 +/- 9.7 ng/ml; P < 10(-4)), in patients with grad e II or grade III SSc than in patients with grade I SSc (63.2 +/- 20.2 ng/m l versus 45.1 +/- 15.6 ng/ml; P < 10(-2)), in patients with abnormal findin gs on chest radiograms than in patients with normal findings on chest radio grams (67.6 +/- 22.4 ng/ml versus 50.4 +/- 21.6 ng/ml; P < 0.05), and in pa tients with cutaneous scars or ulcers than in patients without these manife stations (60.9 +/- 25.9 ng/ml versus 47.2 +/- 13.3 ng/ml; P < 10(-2)). Conclusion. Circulating endostatin concentrations are significantly increas ed in patients with SSc, Production of endostatin may result from tissular sclerosis and could contribute to the development of ischemic manifestation s.