GDF15 and metabolic dysfunction-associated steatotic liver disease: We found that GDF15 expression was mostly confined to the liver and that weight loss induced by LAGB was associated with reduced hepatic (but not adipose tissue) expression of GDF15. Mediators of metabolic inflammation such as IL-1β and tunicamycin induced hepatic GDF15 expression in hepatocytes and IL-1β expression correlated with GDF15 expression in the liver of NAFLD patients.