Regulation of insulin-like growth factor binding protein-1 (IGFBP-1) in insulin-dependent diabetes mellitus. Effects of hyperglycaemia and insulin.
The aim of the present study was to characterize the effect of 44 h of hyperglycaemia on diurnal levels of insulin-like growth factor binding protein-1 (IGFBP-1), insulin-like growth factor-1 (IGF-1), growth hormone (GH) and glucagon in 7 well-controlled subjects with insulin-dependent diabetes mellitus (IDDM). Hyperglycaemia (approximately 15 mmol/l) was induced by a glucose infusion, while the degree of insulinisation was similar to that of a corresponding period with near normoglycaemia (approximately 6.9 mmol/l). Hyperglycaemia for 44 h did not alter the normal diurnal IGFBP-1 levels when the degree of insulinisation was unchanged. The diurnal secretion pattern of IGFBP-1 was preserved in both genders and without any difference between the control and hyperglycaemic periods. However, the IGFBP-1 levels were increased in these IDDM subjects despite a peripheral hyperinsulinemia. An inverse correlation was found between IGFBP-1 and peripheral insulin levels both during periods of rapid changes in IGFBP-1 and insulin concentrations (i.e. morning hours) as well as during the total 24-h sampling period. Total IGF-1 levels were low, but no further decrease was seen after 24 h of hyperglycaemia in the presence of unchanged insulin levels. In conclusion, the present study clearly shows that the increased IGFBP-1 level seen during poor metabolic control in IDDM is not caused by hyperglycaemia. Glucose levels per se do not influence either total IGF-1 or IGFBP-1 concentrations in well-insulinised diabetic patients.
Fowelin
J
J
Department of Internal Medicine, University of Göteborg, Sahlgren's Hospital, Sweden.
Attvall
S
S
von Schenck
H
H
Smith
U
U
Lager
I
I
Hall
K
K
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002352:Carrier Proteins / Q000097:blood*; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism*; D005260:Female; D005934:Glucagon / Q000378:metabolism; D013006:Growth Hormone / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism*; D007329:Insulin Antagonists / Q000378:metabolism; D018970:Insulin-Like Growth Factor Binding Protein 1; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male
D001786:Blood Glucose; D002352:Carrier Proteins; D007328:Insulin; D007329:Insulin Antagonists; D018970:Insulin-Like Growth Factor Binding Protein 1; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D005934:Glucagon