Onslev, J and Jacobson, G and Narkowicz, C and Backer, V and Kalsen, A and Kreiberg, M and Jessen, S and Bangsbo, J and Hostrup, M, Beta2‑adrenergic stimulation increases energy expenditure at rest, but not during submaximal exercise in active overweight men, European Journal of Applied Physiology, 117, (9) pp. 1907-1915. ISSN 1439-6319 (2017) [Refereed Article]
Copyright 2017 Springer-Verlag GmbH Germany
Purpose: β2-Agonists have been proposed as weight-loss treatment, because they elevate energy expenditure. However, it is unknown what effect β2-agonists have on energy expenditure in overweight individuals. Furthermore, the influence of β2-agonist R- and S-enantiomer ratio for the increased energy expenditure is insufficiently explored.
Methods: Nineteen males were included in the study of which 14 completed. Subjects were 31.6 (± 3.5) years [mean (± 95% CI)] and had a fat percentage of 22.7 (± 2.1)%. On separate days, subjects received either placebo or inhaled racemic (rac-) formoterol (2 × 27 µg). After an overnight fast, energy expenditure and substrate oxidation were estimated by indirect calorimetry at rest and during submaximal exercise. Plasma (R,R)- and (S,S)-formoterol enantiomer levels were measured by ultra-performance liquid chromatograph–mass spectrometry.
Results: At rest, energy expenditure and fat oxidation were 12% (P ≤ 0.001) and 38% (P = 0.006) higher for rac-formoterol than placebo. Systemic (R,R):(S,S) formoterol ratio was correlated with change in energy expenditure at rest in response to rac-formoterol (r = 0.63, P = 0.028), whereas no association was observed between fat percentage and rac-formoterol-induced change in energy expenditure. During exercise, energy expenditure was not different between treatments, although carbohydrate oxidation was 15% higher (P = 0.021) for rac-formoterol than placebo. Rac-formoterol-induced shift in substrate choice from rest to exercise was related to plasma ln-rac-formoterol concentrations (r = 0.75, P = 0.005).
Conclusion: Selective β2-adrenoceptor agonism effectively increases metabolic rate and fat oxidation in overweight individuals. The potential for weight loss induced by β2-agonists may be greater for R-enantiopure formulations.
|Item Type:||Refereed Article|
|Keywords:||beta2-agonist, energy expenditure, obesity, sympathomimetics, substrate choice, adrenergic, energy consumption, respiratory exchange ratio|
|Research Division:||Biomedical and Clinical Sciences|
|Research Group:||Pharmacology and pharmaceutical sciences|
|Research Field:||Clinical pharmacology and therapeutics|
|Objective Group:||Clinical health|
|Objective Field:||Clinical health not elsewhere classified|
|UTAS Author:||Jacobson, G (Associate Professor Glenn Jacobson)|
|UTAS Author:||Narkowicz, C (Dr Christian Narkowicz)|
|Web of Science® Times Cited:||9|
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