Also interesting is the fact that the phenotype observed in DIO WT mice treated with IL-6 is reminiscent of leptin-deficient animals such as the obese Zucker rat model, which shows hyperleptinemia, increased amounts of IL-6 and glucose, and suffers dyslipidaemia, diabetes and steatosis [46], thus suggesting a tight link between both IL-6 and the leptin signalling systems in the liver. The gene discussed is LEP; the disease is diabetes mellitus.