TY - JOUR
T1 - Beta2-adrenergic stimulation increases energy expenditure at rest, but not during submaximal exercise in active overweight men
AU - Onslev, Johan
AU - Jacobson, Glenn A
AU - Narkowicz, Christian K
AU - Backer, Vibeke
AU - Kalsen, Anders
AU - Kreiberg, Michael
AU - Jessen, Søren
AU - Bangsbo, Jens
AU - Hostrup, Morten
N1 - CURIS 2017 NEXS 202
PY - 2017
Y1 - 2017
N2 - 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.
AB - 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.
KW - Sympathomimetics
KW - Substrate choise
KW - Adrenergic
KW - Energy consumption
KW - Respiratory exchange
U2 - 10.1007/s00421-017-3679-9
DO - 10.1007/s00421-017-3679-9
M3 - Journal article
C2 - 28702809
VL - 117
SP - 1907
EP - 1915
JO - European Journal of Applied Physiology
JF - European Journal of Applied Physiology
SN - 1439-6319
IS - 9
ER -