The present invention relates to the field of metabolic research. Metabolic disorders, such as obesity, are a public health problem that is serious and widespread. GSSP4 polypeptides have been identified that are believed to be beneficial in the treatment of metabolic disorders. These compounds should be effective for reducing cholesterol levels, body mass, body fat, and for treating metabolic-related diseases and disorders. The metabolic-related diseases or disorders include, but are not limited to, obesity, hyperlipidemia, hypercholesterolemia, atherosclerosis, diabetes, glucose intolerance, insulin resistance and hypertension.