TY - JOUR
T1 - Opposite effects of pioglitazone and rosiglitazone on mitochondrial respiration in skeletal muscle of patients with type 2 diabetes
AU - Rabøl, R
AU - Boushel, R
AU - Almdal, T
AU - Hansen, Christina Neigaard
AU - Ploug, Thorkil
AU - Haugaard, S B
AU - Prats Gavalda, Clara
AU - Madsbad, S
AU - Dela, F
PY - 2010/9
Y1 - 2010/9
N2 - Aim: Skeletal muscle insulin resistance has been linked to mitochondrial dysfunction. We examined how improvements in muscular insulin sensitivity following rosiglitazone (ROSI) or pioglitazone (PIO) treatment would affect muscle mitochondrial function in patients with type 2 diabetes mellitus (T2DM).Methods: Muscle biopsies were obtained from 21 patients with T2DM before and after 12 weeks on either ROSI (4 mg once daily) [n = 12; age, 59.2 ± 2.2 years; body mass index (BMI), 29.6 ± 0.7 kg/m2] or PIO (30 mg once daily) (n = 9; age, 56.3 ± 2.4 years; BMI, 29.5 ± 1.5 kg/m2). An age- and BMI-matched control group was also included (n = 8; age, 61.8 ± 2.3 years; BMI, 28.4 ± 0.6 kg/m2). Insulin sensitivity, citrate synthase- and β-hydroxyacyl-CoA-dehydrogenase (HAD) activity, intramuscular triglyceride (IMTG) and protein content of complexes I-IV were measured, while mitochondrial respiration per milligram muscle was measured in saponin-treated skinned muscle fibres using high-resolution respirometry.Results: Mitochondrial respiration per milligram muscle was lower in T2DM compared to controls at baseline and decreased during ROSI treatment but increased during PIO treatment. Citrate synthase activity and average protein content of complexes I-IV were unchanged in the ROSI group, but protein content of complexes II and III increased during PIO treatment. Insulin sensitivity improved in all patients, but IMTG levels were unchanged.Conclusions: We show opposite effects of ROSI and PIO on mitochondrial respiration, and also show that insulin sensitivity can be improved independently of changes in mitochondrial respiration. We confirm that mitochondrial respiration is reduced in T2DM compared to age- and BMI-matched control subjects.
AB - Aim: Skeletal muscle insulin resistance has been linked to mitochondrial dysfunction. We examined how improvements in muscular insulin sensitivity following rosiglitazone (ROSI) or pioglitazone (PIO) treatment would affect muscle mitochondrial function in patients with type 2 diabetes mellitus (T2DM).Methods: Muscle biopsies were obtained from 21 patients with T2DM before and after 12 weeks on either ROSI (4 mg once daily) [n = 12; age, 59.2 ± 2.2 years; body mass index (BMI), 29.6 ± 0.7 kg/m2] or PIO (30 mg once daily) (n = 9; age, 56.3 ± 2.4 years; BMI, 29.5 ± 1.5 kg/m2). An age- and BMI-matched control group was also included (n = 8; age, 61.8 ± 2.3 years; BMI, 28.4 ± 0.6 kg/m2). Insulin sensitivity, citrate synthase- and β-hydroxyacyl-CoA-dehydrogenase (HAD) activity, intramuscular triglyceride (IMTG) and protein content of complexes I-IV were measured, while mitochondrial respiration per milligram muscle was measured in saponin-treated skinned muscle fibres using high-resolution respirometry.Results: Mitochondrial respiration per milligram muscle was lower in T2DM compared to controls at baseline and decreased during ROSI treatment but increased during PIO treatment. Citrate synthase activity and average protein content of complexes I-IV were unchanged in the ROSI group, but protein content of complexes II and III increased during PIO treatment. Insulin sensitivity improved in all patients, but IMTG levels were unchanged.Conclusions: We show opposite effects of ROSI and PIO on mitochondrial respiration, and also show that insulin sensitivity can be improved independently of changes in mitochondrial respiration. We confirm that mitochondrial respiration is reduced in T2DM compared to age- and BMI-matched control subjects.
KW - Body Mass Index
KW - Cell Respiration
KW - Diabetes Mellitus, Type 2
KW - Female
KW - Hemoglobin A, Glycosylated
KW - Humans
KW - Hypoglycemic Agents
KW - Immunohistochemistry
KW - Insulin Resistance
KW - Male
KW - Middle Aged
KW - Mitochondria, Muscle
KW - Muscle, Skeletal
KW - Thiazolidinediones
U2 - 10.1111/j.1463-1326.2010.01237.x
DO - 10.1111/j.1463-1326.2010.01237.x
M3 - Journal article
C2 - 20649633
SN - 1463-1326
VL - 12
SP - 806
EP - 814
JO - Diabetes, Obesity and Metabolism Online
JF - Diabetes, Obesity and Metabolism Online
IS - 9
ER -