Rosiglitazone is a thiazolidinedione insulin sensitizer that activates PPARγ, decreasing blood glucose and insulin levels. Rosiglitazone exhibits anti-diabetic, anti-inflammatory, antioxidative, anticancer, anti-angiogenic, antihypertensive, and anti-fibrotic activities. In vivo, rosiglitazone decreases LPS-stimulated production of TNF-α, IL-1β, and IL-6 as well as activity of myeloperoxidase; it also inhibits activation of NF-κB, preventing mastitis. In multiple myeloma cells, rosiglitazone suppresses expression of HIF-1α and IGF-1, decreases activation of Aky, and ERK, and inhibits cell viability and proliferation. This compound also inhibits endothelin-1-induced vasoconstriction in a NO-dependent manner in animal models of pulmonary arterial hypertension. Additionally, rosiglitazone prevents activation of AP-1, production of collagen, and differentiation in fibroblasts.