Increased oxidized low density lipoprotein associated with high ceruloplasmin activity in patients with active acromegaly.
OBJECTIVE
Active acromegaly is associated with increased mortality from cardiovascular causes. Several studies have shown increased atherogenic risk factors and biomarkers of inflammation and atherosclerosis in association with growth hormone excess. The aim of this study was to evaluate oxidized low density lipoprotein (oxLDL) levels and some modulators of LDL oxidative modification in patients with acromegaly.


METHODS
Open transversal study.


METHODS
Fifteen patients with active acromegaly and 15 controls were studied.


METHODS
We evaluated the levels of oxLDL, thiobarbituric acid reactive substances (TBARS), ceruloplasmin, bilirubin, uric acid and total reactive antioxidant potential, and the activities of ceruloplasmin, myeloperoxidase, superoxide distmutase, paraoxonase 1, and platelet activating factor acethylhydrolase. Statistical analysis was performed including body mass index as a covariate or as a fixed variable.


RESULTS
Patients with acromegaly showed significantly higher levels of oxLDL (120 +/- 19 vs. 86 +/- 20 U/l, P < 0.001) and endothelin (P < 0.05), increased ceruloplasmin activity (P < 0.01) and a trend towards higher values in TBARS concentration (P = 0.07) in comparison to healthy controls. OxLDL was positively associated with GH, IGF-I and its binding protein 3 (r = 0.63, P < 0.001; r = 0.53, P < 0.01; and r = 0.56, P < 0.01; respectively). OxLDL showed direct associations with endothelin-1 (r = 0.53, P < 0.01) and ceruloplasmin activity (r = 0.43, P < 0.05). The other parameters evaluated were similar in both groups.


CONCLUSIONS
The increase in plasma oxLDL levels, a direct marker of the plaque formation, could constitute a link between atherosclerosis and active acromegaly. LDL oxidation would not be the consequence of diminished antioxidant defences, but of an enhancement in prooxidant factors like ceruloplasmin.
Boero
L
L
Department of Clinical Biochemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, INFIBIOC, CONICET. lauraboero@fibertel.com.ar
Cuniberti
L
L
Magnani
N
N
Manavela
M
M
Yapur
V
V
Bustos
M
M
Gómez Rosso
L
L
Meroño
T
T
Marziali
L
L
Viale
L
L
Evelson
P
P
Negri
G
G
Brites
F
F
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000097:blood; D000172:Acromegaly / Q000097:blood* / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001663:Bilirubin / Q000097:blood; D015992:Body Mass Index; D002570:Ceruloplasmin / Q000032:analysis*; D019332:Endothelin-1 / Q000097:blood; D005260:Female; D019382:Human Growth Hormone / Q000097:blood / Q000378:metabolism; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009195:Peroxidase / Q000097:blood; D013482:Superoxide Dismutase / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014527:Uric Acid / Q000097:blood
D019332:Endothelin-1; D018972:Insulin-Like Growth Factor Binding Protein 3; D008077:Lipoproteins, LDL; D017392:Thiobarbituric Acid Reactive Substances; C099252:oxidized low density lipoprotein; D019382:Human Growth Hormone; D014527:Uric Acid; D007334:Insulin-Like Growth Factor I; D009195:Peroxidase; D013482:Superoxide Dismutase; D002570:Ceruloplasmin; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase; D001663:Bilirubin