Aerobic exercise training improves atrial natriuretic peptide and catecholamine-mediated lipolysis in obese women with polycystic ovary syndrome.
OBJECTIVE
The aim was to investigate the impact of polycystic ovary syndrome (PCOS) on the regulation of lipolysis by catecholamine and for the first time atrial natriuretic peptide (ANP) before and after 16 wk of aerobic training.


METHODS
Eight hyperandrogenic obese women with PCOS [age, 25 +/- 1 yr; body mass index (BMI), 32.0 +/- 1.6 kg/m(2)] and seven healthy BMI-matched controls participated. Studies were performed before and after a 16-wk exercise training program in women with PCOS and cross-sectionally in a group of BMI-matched controls.


METHODS
Lipolysis was measured in vitro in isolated adipocytes and in vivo by microdialysis of sc abdominal adipose tissue before and during a hyperinsulinemic euglycemic clamp.


RESULTS
In vitro, baseline and maximal ANP- and isoproterenol-induced lipolysis was markedly reduced in PCOS women. Baseline (P < 0.001) and ANP-(P < 0.01) and isoproterenol-(P < 0.001) mediated lipolysis, however, was remarkably increased after training, independent of changes in body weight and sex hormones. These functional improvements were supported by an increased 1) lipolytic sensitivity for ANP (1.3-fold; P < 0.05); 2) lipolytic responsiveness for isoproterenol (1.7-fold; P < 0.01); and 3) postreceptor-acting agent dibutyryl-cAMP (activating cAMP-dependent protein kinase) (2.1-fold; P < 0.05). In vivo, the lipolytic responsiveness to isoproterenol was also reduced in PCOS and tended to increase after exercise training. The insulin suppression of lipolysis during the hyperinsulinemic euglycemic clamp was also reduced in PCOS.


CONCLUSIONS
Together, these data show that the regulation of lipolysis by the main endocrine hormones is impaired in women with PCOS. These lipolytic defects can be partly reversed by aerobic exercise training independent of changes in body fat mass and sex hormones.
Moro
Cedric
C
Pennington Biomedical Research Center, Baton Rouge, Louisiana 70808, USA.
Pasarica
Magdalena
M
Elkind-Hirsch
Karen
K
Redman
Leanne M
LM
D000328:Adult; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D015992:Body Mass Index; D002395:Catecholamines / Q000494:pharmacology*; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D008066:Lipolysis / Q000187:drug effects* / Q000502:physiology; D017551:Microdialysis; D009765:Obesity / Q000150:complications / Q000378:metabolism / Q000628:therapy*; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000378:metabolism / Q000628:therapy*; D055815:Young Adult
D002395:Catecholamines; D007328:Insulin; D009320:Atrial Natriuretic Factor; D007545:Isoproterenol