Protein expression levels of SIRT6, NF-κB, PPAR-γ and SREBP-1 in abdominal adipose tissue. (A) SIRT6, (B) NF-κB, (C) PPAR-γ, and (D) SREBP-1 protein levels determined by Western blot analysis of abdominal adipose tissue homogenates from obese normoglycaemic, obese pre-diabetic patients plus metformin (Met) and obese pre-diabetic patients treated with placebo. Inset, representative images of Western blot analysis. Lane 1, obese normoglycaemic patient; lane 2, obese pre-diabetic+ Met; lane 3, obese pre-diabetic + placebo. Data are mean ± SD. * p < 0.01 vs. obese normoglycemic patients; ‡
p < 0.01 vs. obese pre-diabetic + placebo; ¶
p < 0.05 vs. obese pre-diabetic + placebo.