Circulating insulin-like growth factor system changes in women with acute estrogen deficiency induced by GnRH agonist.
This prospective longitudinal study was undertaken to examine the short-term effects (6 months) of estrogen withdrawal on the circulating IGF system. A series of 40 patients suffering from endometriosis was studied before and after a 6-month treatment period with gonadotrophin releasing hormone (GnRH) agonist and calcium, with or without nasal salmon calcitonin. The plasma concentrations of insulin-like growth factor I (IGF-I) and insulin-like growth factor II (IGF-II) were measured by radioimmunoassay and radioreceptor assay respectively. Plasma IGF binding proteins (IGFBPs) were quantified and characterized by ligand blot and immunoblot. In all patients, a secondary hypoestrogenism was observed, including a 4% decrease in lumbar bone mineral density (L-BMD). The plasma IGF-I and IGF-II concentrations increased after treatment (24%, p < 0.0005 and 40%, p < 0.004 respectively), with no significant difference between the treatment groups. There was a positive correlation between plasma IGF-I (but not IGF-II) changes and changes in urinary deoxypyridinoline (r = 0.32, p < 0.05), urinary C telopeptide of type 1 collagen (r = 0.33, p < 0.04) and total plasma alkaline phosphatases (r = 0.33, p < 0.04). No correlation was found between IGF-I and L-BMD changes, while there was a positive correlation between the changes in plasma IGF-II and L-BMD (r = 0.32, p < 0.05). Ligand blot analysis revealed a significant increase in IGF-II binding to a 29-31 kilodalton region where positive staining with specific antibodies to IGFBP-3 or IGFBP-1 was observed. In conclusion, IGF-I and IGF-II plasma concentrations are both increased following a short period of treatment with a GnRH agonist. The changes in individual IGF peptides are differently correlated with changes in markers of bone remodelling and L-BMD.
Poiraudeau
S
S
Service de Rééducation et de Réadaptation de l'Appareil Locomoteur et des Pathologies du Rachis, Hôpital Cochin, Paris, France.
Roux
C
C
De Ceuninck
F
F
Tsagris
L
L
Borderie
D
D
Cherruau
B
B
Dumontier
M F
MF
Corvol
M
M
D000208:Acute Disease; D000328:Adult; D015153:Blotting, Western; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004967:Estrogens / Q000172:deficiency; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000187:drug effects / Q000378:metabolism*; D007335:Insulin-Like Growth Factor II / Q000187:drug effects / Q000378:metabolism*; D008186:Luteolytic Agents / Q000494:pharmacology*; D011446:Prospective Studies; D017329:Triptorelin Pamoate / Q000494:pharmacology*
D004967:Estrogens; D018969:Insulin-Like Growth Factor Binding Proteins; D008186:Luteolytic Agents; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II