The influence of weight loss on serum osteoprotegerin concentration in obese perimenopausal women.
OBJECTIVE
To assess the influence of weight reduction therapy on serum osteoprotegerin (OPG) concentration in obese patients and compare these results with normal-weight controls.


METHODS
Forty-three obese women (BMI, 36.7 +/- 4.1 kg/m2; mean age, 50.1 +/- 4.5 years) were studied. The control group consisted of 19 normal-weight women (BMI, 24.2 +/- 2.1 kg/m2; mean age, 53.8 +/- 5.2 years). In all patients, serum concentrations of OPG, C telopeptide of type I collagen containing the cross-linking site (CTX), osteocalcin, parathormone, 25-(OH)-D3 (vitamin D), and total calcium and phosphorus were assessed before and after a 3-month weight reduction therapy.


RESULTS
In obese subjects, serum concentrations of OPG, 25-(OH)-D3, osteocalcin, total calcium, and phosphorus were significantly lower, and serum concentration of parathormone was significantly higher, before weight reduction therapy in comparison with normal-weight controls. After weight reduction, a significantly higher serum concentration of 25-(OH)-D3 and CTX and significantly lower concentration of OPG were found.


CONCLUSIONS
Serum concentration of OPG was significantly lower in obese patients in comparison with normal-weight controls. Weight reduction therapy resulted in further decrease in OPG serum concentrations. Therefore, OPG cannot be treated as a protective factor from bone loss in obese patients.
Holecki
Michał
M
Department of Pathophysiology, Medical University of Silesia in Katowice, ul. Medyków 18, 40-752 Katowice, Poland. holomed@poczta.onet.pl
Zahorska-Markiewicz
Barbara
B
Janowska
Joanna
J
Nieszporek
Teresa
T
Wojaczyńska-Stanek
Katarzyna
K
Zak-Gołab
Agnieszka
A
Wiecek
Andrzej
A
D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology; D002112:Calcifediol / Q000097:blood; D002118:Calcium / Q000097:blood; D024042:Collagen Type I / Q000097:blood; D005260:Female; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000378:metabolism; D015675:Osteocalcin / Q000097:blood; D053244:Osteoprotegerin / Q000097:blood* / Q000378:metabolism; D010281:Parathyroid Hormone / Q000097:blood; D010455:Peptides / Q000097:blood; D010758:Phosphorus / Q000097:blood; D015431:Weight Loss / Q000502:physiology*; D014965:X-Rays
D024042:Collagen Type I; D053244:Osteoprotegerin; C470125:PTH protein, human; D010281:Parathyroid Hormone; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D010758:Phosphorus; D002112:Calcifediol; D002118:Calcium