Novel biomarkers of human growth hormone action from serum proteomic profiling using protein chip mass spectrometry.
BACKGROUND
The detection of exogenous human GH (hGH) administration in athletes poses unique analytical problems, because its short circulating half-life provides only a brief opportunity to detect the administered hormone above endogenous levels. Measurement of novel GH-regulated serum protein biomarkers might provide an indirect method to detect exogenous GH.


OBJECTIVE
The objective of this study was to identify new serum biomarkers of GH administration using proteomic profiling.


METHODS
Sera from a previously reported, double-blind, placebo-controlled GH administration trial were analyzed by protein chip mass spectrometry.


METHODS
The study was performed at clinical research centers.


METHODS
Sixty healthy subjects, aged 18-40 yr, who were not elite athletes, were studied.


METHODS
Placebo or recombinant hGH treatment (0.1 or 0.2 IU/kg.d; 20 subjects/group) was administered for 4 wk, followed by an 8-wk washout period.


METHODS
Protein mass profiles were determined on immobilized Cu(2+) chips on d 0 and 21 of GH administration, and multivariate analysis was used to classify subjects into GH and placebo administration groups.


RESULTS
When assessed by cross-validation, the classification performance of classifiers based on multivariate analysis of several GH-regulated peaks performed no better than classifiers based on the single best peak. This peak, a prominent biomarker of 15.1 kDa, was purified and identified as hemoglobin alpha-chain. The time course of the GH response of this biomarker is similar to that of other GH-dependent markers, such as IGF-I.


CONCLUSIONS
This study demonstrates that protein mass profiling is an effective tool for the detection of GH administration and suggests that measurement of hemoglobin alpha-chain may have utility as a novel serum biomarker of GH action.
Chung
Liping
L
Kolling Institute of Medical Research, Royal North Shore Hospital, St. Leonards, New South Wales 2065, Australia.
Clifford
David
D
Buckley
Michael
M
Baxter
Robert C
RC
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D019382:Human Growth Hormone / Q000097:blood* / Q000494:pharmacology; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D015999:Multivariate Analysis; D040081:Protein Array Analysis / Q000379:methods; D040901:Proteomics / Q000379:methods*; D012372:ROC Curve
D015415:Biomarkers; D006442:Glycated Hemoglobin; D019382:Human Growth Hormone