The present invention relates to the field of metabolic research, in particular the discovery of compounds effective for reducing body mass and useful for treating obesity-related diseases and disorders. The obesity-related diseases or disorders envisioned to be treated by the methods of the invention include, but are not limited to, hyperlipidemia, atherosclerosis, insulin resistance, diabetes, and hypertension. In particular, the invention provides for methods of identifying and using AGONISTS and ANTAGONISTS of PROLIXIN activity, wherein said activity is selected from the group consisting of lipid partitioning, lipid metabolism, and insulin-like activity.