Conclusions
Evaluation of the identified proteins provides a novel alternative to traditional markers of GH status, such as serum IGF-I levels, to assess GH therapy in GH deficient adults.
Objective
The objective of the study was to identify novel serum biomarkers of GH treatment in adults with GHD. Design and patients: Eight patients with profound GHD as a consequence of a pituitary adenoma or its treatment were evaluated before and 3 months after GH replacement therapy (0.2-0.4 mg/d). Main outcome measures: Serum proteomic changes were studied using two-dimensional gel electrophoresis and mass spectrometry. Protein profiles were analyzed and compared in serum samples obtained before and after GH treatment.
Results
The levels of six serum protein spots were significantly altered after GH substitution. These proteins were identified as five isoforms of haptoglobin (decreased in posttreatment samples) and one isoform of apolipoprotein A-I (increased in posttreatment samples). Importantly, changes in the levels of the identified proteins were associated with decreases in fat mass and increases in lean mass in all patients. These results were independent of serum IGF-I levels. Conclusions: Evaluation of the identified proteins provides a novel alternative to traditional markers of GH status, such as serum IGF-I levels, to assess GH therapy in GH deficient adults.