My research program focuses on obesity, diabetes and adipokine biology. My basic research efforts utilize genomics-bioinformatics, animal physiology, and molecular biology studies to elucidate the role of new molecules important in energy homeostasis. My current translational /clinical investigations focus mainly on the role of metabolically important hormones, including leptin, irisin and adiponectin as well as their downstream effectors, on energy homeostasis and metabolic abnormalities. Our work spans the entire spectrum from animal physiology and molecular biology, through observational studies, to physiology and pharmacokinetic interventional proof of concept clinical trials in humans on new therapeutic agents important in the treatment of the above disorders. Recent major contributions by my research group include the elucidation of the physiological role and potential diagnostic and therapeutic utility of leptin in human physiology and pathophysiology. We were the first to prove the role of leptin in mediating the neuroendocrine response to food deprivation in rodents and later in humans, and the first to publish leptin pharmacokinetic studies in humans. We also were the first to publish proof-of-concept studies demonstrating the role of leptin in the etiology and therapy of conditions such as exercise-induced amenorrhea and HIV-induced lipoatrophy. We have recently extended these findings with further randomized clinical trials and combination therapies. Our work has resulted in more than 800 publications that have received more than 72,000 citations with an h-index of 121. Our work has also resulted in patents for diagnostic and therapeutic applications, has directly contributed to the development of new pharmaceuticals by major pharmaceutical companies, and has contributed to the creation of a new startup, Intekrin, Inc.