Project description:The goal of this study was to analyse the effect of a 12 weeks treatment with rosiglitazone on insulin sensitivity in the adipose tissue of type 2 diabetic patients. Diabetic patients were submitted to a 3 hours hyperinsulinemic- euglycemic clamp. Adipose tissue biopsies were taken before and after the clamp, labelled A & B respectively. Then, the patients were treated with rosiglitazone, agonist of PPAR gamma, during 12 weeks. After the treatment, all the patients were submitted to a second 3 hours hyperinsulinemic-euglycemic clamp. Adipose tissue biopsies were taken before and after the clamp, labelled C & D respectively.
Project description:The goal of this study was to analyse the effect of a 12 weeks treatment with rosiglitazone on gene expression in adipose tissue of type 2 diabetic patients. Diabetic patients were treated with rosiglitazone, agonist of PPAR gamma, during 12 weeks. Adipose tissue biopsies were taken before and after the treatment.
Project description:The goal of this study was to analyse the effect of a 12 weeks treatment with rosiglitazone on insulin sensitivity in the muscle of type 2 diabetic patients. Ten diabetic patients were submitted to a 3 hours euglycemic-hyperinsulinemic clamp. Skeletal muscle biopsies were taken before and after the clamp. Samples from the same patients (obtained before and after the clamp) were hybridized on the same microarray. Biopsie taken before the clamp was considered as the control. Then, the patients were treated with rosiglitazone, agonist of PPAR gamma, during 12 weeks. After the treatment, all the patients were submitted to a second 3 hours euglycemic-hyperinsulinemic clamp. Skeletal muscle biopsies for 7 patients were taken before and after the clamp. Samples from the same patients (obtained before and after the clamp) were hybridized on the same microarray. Biopsie taken before the clamp was considered as the control. Set of arrays that are part of repeated experiments Compound Based Treatment: patient biopsies taken before (no) and after (yes) rosiglitazone (TZD) treatment`
Project description: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
Project description:Background: The prevalence of type 2 diabetes has increased dramatically in recent decades. Increasing brown adipose tissue (BAT) mass and activity has recently emerged as an interesting approach to not only increase energy expenditure, but also improve glucose homeostasis. BAT can be recruited by prolonged cold exposure in lean, healthy humans. Here, we tested whether cold acclimation could have therapeutic value for patients with type 2 diabetes by improving insulin sensitivity. Methods: Eight type 2 diabetic patients (age 59.3±5.8 years, BMI 29.8±3.2 kg/m2) followed a cold acclimation protocol, consisting of intermittent cold exposure (6 hours/day, 14-14.5 °C) for 12 consecutive days. Before and after cold acclimation, cold-induced BAT activity was assessed by [18F]FDG-PET/CT scanning, insulin sensitivity at thermoneutrality by a hyperinsulinemic-euglycemic clamp, and muscle and WAT biopsies were taken. Results: Cold-induced BAT activity was low, but increased in all patients upon cold acclimation (SUV from 0.40±0.29 to 0.63±0.78, p<0.05). Interestingly, insulin sensitivity showed a very pronounced 40% increase upon cold acclimation (glucose rate of disappearance from 14.9±4.1 to 20.5±6.9 μmol kg-1 min-1, p<0.05). A 40% increase in insulin sensitivity cannot be explained by BAT glucose uptake, in fact basal skeletal muscle GLUT4 content and translocation was markedly increased after cold acclimation, without effects on insulin signaling or AMPk activation. Conclusions: Regular mild cold exposure has marked effects on insulin sensitivity, which are accompanied by small increases in BAT activity and more pronounced effects on skeletal muscle. These data suggest a novel therapeutic option for the treatment of type 2 diabetes. Microarray analysis was performed on abdominal subcutaneous white adipose tissue samples from human type 2 diabetic patients before, and after 10 days of cold acclimation. A total of 14 samples, from 7 subjects, were used for the microarray analysis.
Project description:We characterized the insulin sensitivity and multi-tissue gene expression profiles of lean and insulin resistant, obese Zucker rats untreated or treated with one of four PPARγ ligands (pioglitazone, rosiglitazone, troglitazone, and AG035029). We analyzed the transcriptional profiles of adipose tissue, skeletal muscle, and liver from the rats and determined whether ligand insulin-sensitizing potency was related to ligand-induced alteration of functional pathways. Ligand treatments improved insulin sensitivity in obese rats, albeit to varying degrees. Male Zucker fatty (fa/fa) and lean (fa/+) rats (Charles River, Wilmington, MA) were received at 6 weeks of age. Fatty rats were weight-matched upon arrival and randomly divided into one of five experimental groups. The fatty rat groups varied by the type of chow they were fed - normal chow alone or with a PPARγ ligand admixture: normal chow (fatty control, FC), rosiglitazone-treated (Rosi), pioglitazone-treated (Pio), troglitazone-treated (Tro), or AG035029-treated (AG). Lean control (LC) rats were all fed normal chow. Rats groups were maintained on the diets for 21 days. Adipose tissue (epididymal), skeletal muscle (gastrocnemius), and liver were harvested from lean (LC) and insulin resistant, obese Zucker rats untreated (FC) or treated with one of four PPARγ ligands (pioglitazone [Pio], rosiglitazone [Rosi], troglitazone [Tro], and AG035029 [AG]).
Project description:Impaired resistance to insulin, the key defect in type 2 diabetes (T2D), is associated with a low capacity to adapt fuel oxidation to fuel availability, i.e., metabolic inflexibility. The hampered metabolic adaptability triggers a further damage of insulin signaling. Since skeletal muscle is the main site of glucose uptake, effectiveness of T2D treatment depends in large on the improvement of insulin sensitivity and metabolic adaptability of the muscle. We have shown previously in mice fed an obesogenic high-fat diet that a combination treatment using n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) and thiazolidinedione (TZD) anti-diabetic drugs preserved metabolic health and synergistically improved muscle insulin sensitivity. We investigated here whether TZD rosiglitazone could elicit the additive beneficial effects on metabolic flexibility when combined with n-3 LC-PUFA. Adult male C57BL/6J mice were fed an obesogenic corn oil-based high-fat diet (cHF) for 8 weeks, or randomly assigned to various dietary treatments: (i) cHF+F, cHF with n-3 LC-PUFA concentrate replacing 15% of dietary lipids; (ii) cHF+ROSI, cHF with 10 mg rosiglitazone/kg diet; and (iii) cHF+F+ROSI, or chow-fed. Indirect calorimetry demonstrated superior preservation of metabolic flexibility to carbohydrates in response to the combination treatment. Metabolomic and gene expression analyses in the muscle suggested distinct and complementary effects of the single treatments, with rosiglitazone augmenting insulin sensitivity by the modulation of branched-chain amino acid metabolism, and n-3 LC PUFA supporting complete oxidation of fatty acids in mitochondria. These beneficial metabolic effects were associated with the activation of the switch between glycolytic and oxidative muscle fibers, especially in the cHF+F+ROSI mice. Our results further support the idea that the combination treatment using n-3 LC-PUFA and TZDs could improve the efficacy of the treatment of obese and diabetic patients.