NAFLD is a spectrum of liver diseases associated with varying degrees of hepatic steatosis, inflammation, and in some cases, fibrosis. NAFLD is a common observation in all demographics, but the prevalence of NAFLD and nonalcoholic steatohepatitis (NASH) is especially high in the morbidly obese population. Leptin is a cytokine that is encoded by the ob gene and primarily secreted by adipose tissue. The production of serum leptin increases with progressive obesity. Because of this observation, there has been significant interest in potential role of leptin in NAFLD.

Our hypothesis is that we will find increased hepatic leptin and leptin receptor expression as the degree of hepatic injury worsens in NAFLD.

Inclusion Criteria:

• All patients undergoing elective bariatric surgery, ages 18-65.

Exclusion Criteria:

• non-obese patients, ages less than 18 and over 65. Pregnant patients.

Patients scheduled for bariatric surgery