The objective was to study the effect of recombinant
human growth hormone (rhGH) administration to patients with chronic
malnutrition maintained on
total parenteral nutrition (TPN) on the levels of
insulin-like growth factor-I (
IGF-I) and
IGF binding proteins (IGFBPs) during a double-blind trial. After 1 week of TPN the patients were randomized into group I (placebo) or group II (rhGH). Samples were collected on the first day (start of the TPN) to measure basal values, the seventh day to study the effect of TPN and the 10th, 14th and 21st days to evaluate the rhGH effect. Basal laboratory evaluation, nutritional status and
glucose tolerance were assessed using standard laboratory techniques. Radioimmunoassays were used to analyse
IGF-I, free
IGF-I (fIGF-I) and IGFBP1-3. Electrophoresis with Western
ligand blotting and Western immunoblotting was applied to find the pattern of IGFBPs. TPN had no effect on the circulating
IGF-I concentration and the pattern of IGFBPs present in the studied groups of patients. The rhGH administration led to significant increases of
IGF-I, total
IGFBP-3, glycosylated
IGFBP-3 (39, 42 kDa) and the 29 kDa fragment of
IGFBP-3 and the decrease of
IGFBP-2 during the trial (P<0.05). The mean levels of
IGFBP-1, fIGF-I and the parameters of nutritional status in group II during the trial were not significantly influenced by rhGH. However, it has been found that
IGFBP-1 and fIGF-I levels were correlated with the levels of the weekly
nitrogen balance of each patient in group II at the end of the trial. In spite of the significant changes of
IGF-I,
IGFBP-2, total
IGFBP-3 and
IGFBP-3 (29 kDa proteolytic fragment) after rhGH administration to patients with
malnutrition, maintained on
parenteral nutrition, the increase of
nitrogen balance was seen only in patients who decreased their
IGFBP-1 and increased bioavailable
IGF-I as reflected by measurement of fIGF-I. The levels of
IGFBP-1 may provide a useful marker of
IGF-I bioavailability in monitoring the efficiency of the rhGH
therapy in malnourished patients.