Role of PPAR-y Agonists in Immunomodulation and Vascular Prevention in SLE (PPAR-SLE)

Systemic lupus erythematosus (SLE) is an autoimmune disease of unclear cause that affects primarily women of childbearing age. Patients with lupus have a significantly increased risk of developing complications of their blood vessels due to accelerated hardening of the arteries (atherosclerosis). These complications include heart attacks and stroke. No drug to date has proven to prevent this type of complication in lupus and premature vascular disease significantly impacts the quality of life of these patients and enhances their risk of death. The thiazolidinediones (TZD) are a class of drugs approved for the treatment of patients with type 2 diabetes mellitus (DM); they belong to the family of drugs that activate the peroxisome proliferator-activated receptor-gamma (PPAR-gamma). They have been proposed to have strong anti-atherogenic and anti-inflammatory effects even in patients without diabetes. Recent work from our group and others indicates that TZDs significantly improve vascular damage, dysfunction of blood vessels and disease activity in mouse models of lupus and abrogate atherosclerosis. We recently identified the TZD pioglitazone as an effective drug in modulation of vascular function and disease activity in patients with rheumatoid arthritis. In addition, we have found in mouse models of lupus and in in vitro experiments with human lupus cells, that pioglitazone has important roles in modulating immune function and vascular manifestations. Furthermore, this drug is not immunosuppressive, adding an additional advantage when compared to other medications used in this disease. We propose that TZDs could significantly improve blood vessel function and play a role in atherosclerosis prevention in human SLE, in addition to modifying lupus disease activity. The major goal of the proposed research is to assess the effects of the PPAR-gamma agonist pioglitazone in SLE on vascular function and inflammation and on SLE disease activity. The results of the study may lead to the characterization of a new therapeutic target with dual effects on lupus and its associated blood vessel damage