This is an interventional, twenty-four week, randomized, double blind, placebo-controlled trial with bromocriptine QR in subjects with newly diagnosed and established type 2 diabetes mellitus (T2DM) to evaluate its effects on the cardiovascular and peripheral autonomic nervous system, as well as on inflammatory markers, the leptin/adiponectin system, hormonal levels of RAS and HPA axis, indices of insulin resistance, and measures of oxidative and nitrosative stress. Forty newly diagnosed diabetes subjects and 40 subjects with established diabetes will be enrolled in the study and each randomized to treatment with bromocriptine-QR or placebo.