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Upon intramuscular entry, fatty acids are converted to amphiphatic fatty acyl-CoAs by action of the acyl-CoA synthetase (ACS) enzymes. While it has been reported that insulin resistant skeletal muscle shows an accumulation of fatty acyl-CoAs, the role of the enzymes which catalyze their synthesis is still sparsely studied in human muscle, in particular the influence of obesity, and insulin resistance. We analyzed muscle biopsies obtained from normal weight controls (n = 7, average BMI 24), males/females with obesity (n = 7, average BMI 31), and males/females with obesity and type 2 diabetes (T2D) (n = 7, average BMI 34), for relevant ACS (long-chain acyl-CoA synthetase 1 (ACSL1), −3 (ACSL3) and − 4 (ACSL4), fatty acid transport protein 1 (FATP1) and − 4 (FATP4)). The mRNA expression was determined by real-time PCR, and total oleoyl-CoA synthetase activity was measured. In the males/females with obesity and T2D, the response to 16 weeks of exercise training with minor weight loss was evaluated. ACSL1 is the dominantly expressed ACS isoform in human skeletal muscle. The content of total ACS mRNA, as well as ACSL1 mRNA, were lower in muscle of males/females with obesity and T2D. Exercise training in the males/females with obesity and T2D increased the total ACS enzyme activity, along with a lowering of the HOMA-IR index. The capacity for synthesis of fatty acyl-CoAs is lower in skeletal muscle of obese males/females with T2D. This suggests a decreased ability to convert fatty acids to fatty acyl-CoAs, which in turn may affect their entry into storage or metabolic pathways in muscle. Thus, the accumulation of fatty acyl-CoAs in the obese or insulin resistant state that has been shown in previous reports is not likely to result from increased fatty acid acylation. The upregulation of ACS activity by exercise training appears beneficial and occurred concomitantly with increased insulin sensitivity., Upon intramuscular entry, fatty acids are converted to amphiphatic fatty acyl-CoAs by action of the acyl-CoA synthetase (ACS) enzymes. While it has been reported that insulin resistant skeletal muscle shows an accumulation of fatty acyl-CoAs, the role of the enzymes which catalyze their synthesis is still sparsely studied in human muscle, in particular the influence of obesity, and insulin resistance. We analyzed muscle biopsies obtained from normal weight controls (n = 7, average BMI 24), males/females with obesity (n = 7, average BMI 31), and males/females with obesity and type 2 diabetes (T2D) (n = 7, average BMI 34), for relevant ACS (long-chain acyl-CoA synthetase 1 (ACSL1), −3 (ACSL3) and − 4 (ACSL4), fatty acid transport protein 1 (FATP1) and − 4 (FATP4)). The mRNA expression was determined by real-time PCR, and total oleoyl-CoA synthetase activity was measured. In the males/females with obesity and T2D, the response to 16 weeks of exercise training with minor weight loss was evaluated. ACSL1 is the dominantly expressed ACS isoform in human skeletal muscle. The content of total ACS mRNA, as well as ACSL1 mRNA, were lower in muscle of males/females with obesity and T2D. Exercise training in the males/females with obesity and T2D increased the total ACS enzyme activity, along with a lowering of the HOMA-IR index. The capacity for synthesis of fatty acyl-CoAs is lower in skeletal muscle of obese males/females with T2D. This suggests a decreased ability to convert fatty acids to fatty acyl-CoAs, which in turn may affect their entry into storage or metabolic pathways in muscle. Thus, the accumulation of fatty acyl-CoAs in the obese or insulin resistant state that has been shown in previous reports is not likely to result from increased fatty acid acylation. The upregulation of ACS activity by exercise training appears beneficial and occurred concomitantly with increased insulin sensitivity.

Aims: Exercise as well as glucagon-like peptide-1 receptor agonist (GLP-1RA) treatment improves glycaemic control in patients with type 2 diabetes. We investigated the effects of exercise in combination with a GLP-1RA (liraglutide) or placebo for the treatment of type 2 diabetes.Methods: Thirty-three overweight, dysregulated and sedentary patients with type 2 diabetes were randomly allocated to 16 weeks of exercise and liraglutide or exercise and placebo. Both groups had three supervised 60-minute training sessions per week including spinning and resistance training.Results: HbA1c levels dropped by 2.0 ± 1.2% (mean ± standard deviation) (from 8.2 ± 1.4%) in the exercise plus liraglutide group vs 0.3 ± 0.9% (from 8.0 ± 1.2%) with exercise plus placebo (p < 0.001), and body weight was reduced more with liraglutide (-3.4 ± 2.9 vs -1.6 ± 2.3 kg, p < 0.001). Compared to baseline, similar reductions were seen in body fat (exercise plus liraglutide: -2.5 ± 1.4%, (p < 0.001); exercise plus placebo: -2.2 ± 1.9%, (p < 0.001)) and similar increases were observed in maximal oxygen uptake (exercise plus liraglutide: 0.5 ± 0.5 l O2 per min (p < 0.001); exercise plus placebo: 0.4 ± 0.4 l O2 per min (p = 0.002)). Greater reductions in fasting plasma glucose (-3.4 ± 2.3 vs -0.3 ± 2.6 mM, p < 0.001) and systolic blood pressure (-5.4 ± 7.4 vs -0.6 ± 11.1 mmHg, p < 0.01) were seen with exercise plus liraglutide vs exercise plus placebo. The two groups experienced similar increases in quality of life during the intervention.Conclusions: In obese patients with type 2 diabetes, exercise combined with GLP-1RA treatment near-normalised HbA1c levels and caused a robust weight loss when compared to placebo. These results suggest that a combination of exercise and GLP-1RA treatment is effective in type 2 diabetes.

In patients with type 2 diabetes, both supervised exercise and treatment with the glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1RA) liraglutide may improve cardiac function. We evaluated cardiac function before and after 16 weeks of treatment with the GLP-1RA liraglutide or placebo, combined with supervised exercise, in 33 dysregulated patients with type 2 diabetes on diet and/or metformin. Early diastolic myocardial tissue velocity was improved by exercise in the placebo group (mean ± standard deviation [s.d.] -7.1 ± 1.6 to -7.7 ± 1.8 cm/s, P = .01), but not in the liraglutide group (-7.1 ± 1.4 to -7.0 ± 1.4 cm/s, P = .60; between groups, P = .02). Similarly, the mean ± s.d. ratio of early and atrial mitral annular tissue velocities improved in the placebo group (1.0 ± 0.4 to 1.2 ± 0.4, P = .003), but not in the liraglutide group (1.0 ± 0.3 to 1.0 ± 0.3, P = .87; between groups, P = .03). We found no significant differences in heart rate, left ventricular (LV) structure or function within or between the groups. In conclusion, the addition of liraglutide to exercise in sedentary patients with dysregulated type 2 diabetes may blunt the suggested beneficial effect of exercise on LV diastolic function.