Effects of bed-time insulin versus pioglitazone on abdominal fat accumulation, inflammation and gene expression in adipose tissue in patients with type 2 diabetes

Aims/hypothesis: Intra-abdominal fat (IAF) and inflammatory markers are correlated with cardio-vascular risk. We compared the impact of bed-time insulin versus pioglitazone treatment on these parameters in type 2 diabetic (T2D) patients. Methods: Twenty-eight T2D patients poorly controlled with metformin and sulfonylurea were randomized to receive add-on therapy with pioglitazone or bed-time NPH insulin. IAF and subcutaneous fat (SCF) content, systemic low-grade inflammation level and expression of inflammation related genes in SCF, were measured before and after 24 weeks of treatment. Results: Insulin and pioglitazone resulted in a significant decrease in HbAlc (-1.6% and -1.2%, respectively) and a significant increase in total body fat mass (1 +/- 2.3 and 3.3 +/- 2.7 kg, respectively). There was no change in IAF content after both treatments whereas significant increase in SCF content was only seen after pioglitazone treatment (p < 0.05 versus insulin). hsCRP level decreased after pioglitazone and ferritin level decreased after insulin treatment. No change in mRNA expression of inflammation related genes was found after either treatment. Conclusion/interpretation: This suggests that a 24-week treatment with pioglitazone or bedtime insulin has a similar impact on intra-abdominal fat mass and systemic low-grade inflammation. (C) 2009 Elsevier Ireland Ltd. All rights reserved.