Insulin therapy increases low plasma growth hormone binding protein in children with new-onset type 1 diabetes.
This study was undertaken (1) to evaluate growth hormone binding protein (GHBP) levels in newly diagnosed patients with Type 1 diabetes before and after insulin therapy and (2) to determine the relationship of GHBP to glycaemic control, C-peptide level and blood pH. GHBP, expressed as a percentage of (125I)GH bound, was determined in 33 patients with Type 1 diabetes (M/F = 19/14, 12.3 +/- 0.4 years) before (day 0), after 5 days (day 5) and after 3 months (month 3) of insulin therapy. At day 0, GHBP was lower in Type 1 diabetes compared with 38 matched healthy control subjects (3.9 +/- 0.4 vs 8.2 +/- 0.4%, p < 0.001). There was no significant improvement in GHBP at day 5 (4.4 +/- 0.3%). At month 3, GHBP increased to (6.0 +/- 0.4%, p < 0.001 vs day 0), but was still lower than controls, p < 0.001. At day 0 GHBP correlated with BMI (r = 0.50, p = 0.001), blood glucose (r = -0.43 p = 0.006) and pH (r = 0.48, p = 0.004), but not HbA1. GHBP at month 3 correlated with day 0 C-peptide (r = 0.41, p = 0.02). Thus, (1) circulating GHBP is low in newly diagnosed patients with Type 1 diabetes, and increases after 3 months of insulin therapy but does not normalize and (2) the severity of biochemical derangement and residual beta-cell function at diagnosis may determine GHBP status and its recovery. We conclude that insulin is an important modulator of GH binding protein in newly diagnosed children with Type 1 diabetes.
Arslanian
S A
SA
Division of Pediatric Endocrinology, Metabolism and Diabetes Mellitus, Children's Hospital, University of Pittsburgh, PA.
Menon
R K
RK
Gierl
A P
AP
Heil
B V
BV
Foley
T P
TP
D000293:Adolescent; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood; D002352:Carrier Proteins / Q000097:blood* / Q000187:drug effects; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000188:drug therapy; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D007328:Insulin / Q000627:therapeutic use*; D008297:Male; D011627:Puberty; D012016:Reference Values; D013997:Time Factors
D002096:C-Peptide; D002352:Carrier Proteins; D006442:Glycated Hemoglobin; D013006:Growth Hormone; D007328:Insulin; C051815:somatotropin-binding protein