The effect of insulin, glucose and rosiglitazone on mouse 3T3-L1 mature adipocytes gene expression . Mus musculus

Obesity is associated with insulin resistance and type 2 diabetes, implying a role for adipose tissue in the etiology of these disorders. We used cDNA microarrays to obtain expression profiles of adipocyte by the treatment of insulin and anti-diabetic drug rosiglitazone at both high and low glucose level. Mouse 3T3-L1 mature adipocytes were treated 2 days 1) with or without 1 µM insulin at low and high glucose level, 2) with or without 0.5 µM rosiglitazone at low and high glucose and insulin level. 1) The comparison between the insulin and non-insulin treatment at the same glucose level showed minor changes in the transcriptome. The expressions of some processing enzymes for extracellular matrix components were regulated by insulin. 2) Transcriptome data indicates that an altered energy metabolism is induced by rosiglitazone in mature adipocytes. In addition, rosiglitazone represses adipokine expression, except adiponectin and ApoE. Moreover, transcriptome changes indicate that a general repression of secreted protein encoding genes occurs. Keywords: homone and drug response Overall design: In the present study, large-scale gene expression analysis was performed to reveal mechanistic details of effect of insulin and rosiglitaonze. 3T3-L1 mature adipocytes were treated 1µM insulin, and/or 0.5 µM rosiglitazone. To assess the influence of glucose on the effects, high (15.75 mM) and low (4.5 mM) glucose levels as background were applied respectively. In parallel, control cells were cultured in the same medium but without insulin or rosiglitazone. Therefore 6 conditions were used: Basal: low glucose no insulin and rosiglitazone; Glc: high glucose; Ins: high insulin; Rosi: with rosiglitazone; Ins+Glc: high glucose and high insulin, Rosi+Ins+Glc: with rosiglitazone, high insulin and high glucose. Total RNA samples (n = 5 from three independent experiments per condition) were individually hybridised to the RIKILT mouse oligo 10K DNA arrays.