Serum levels of adhesion molecules ICAM-1 and VCAM-1 and tissue inhibitor of metalloproteinases, TIMP-1, are elevated in patients with autoimmune thyroid disorders: Relevance to vascular inflammation

Abstract Serum levels of ICAM-1 (Inter Cellular Adhesion Molecule-1), VCAM-1 (Vascular cell Adhesion Molecule-1-I), TIMP-1 (tissue inhibitor of metalloproteinases 1) and MMP-9 (Metalloproteinase 9) are well established markers of inflammation. The physiopathological link between inflammation, atherosclerosis and autoimmunity is well demonstrated. However, serum levels of these biomarkers in patients with autoimmune-mediated dysthyroidism, including their evolution after improvement of the thyroid disorder have not been assessed. So, we evaluated the circulating levels of these markers in autoimmune and in non-autoimmune-mediated dysthyroid patients, and their evolution after treatment of thyroid disease. We conducted a prospective study to evaluate these markers before and after treatment in hyperthyroid patients ( n  = 33; 28 patients with autoimmune disease), hypothyroid patients ( n  = 38; 33 patients with autoimmune disease) and euthyroid subjects ( n  = 33). At baseline, serum levels of ICAM-1, VCAM-1 and TIMP-1 were significantly elevated in patients with hyperthyroidism as compared to euthyroid and hypothyroid patients (respectively p  = 0.0005 and p p p  = 0.002). In hyperthyroid patients, ICAM-1, VCAM-1 and TIMP-1 concentrations fell significantly after they had become euthyroid (respectively p  = 0.0006; p p  = 0.0009), although VCAM-1 values remained higher than those observed in the control group ( p  = 0.005). We found that autoimmune-mediated dysthyroidism were associated with increased peripheral blood concentrations of VCAM-1, ICAM-1 and TIMP-1. Whether these biological abnormalities translate into increase intima remodelling and atherosclerosis remains to be studied.