Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog.
CJC-1295 significantly increases basal and mean GH levels and IGF-I production while preserving GH pulsatility, but the clinical implications of these changes remain unclear.
Where it sits
this study against the rest of the cjc-1295 without dac (modified grf 1-29) corpusSummary and findings
This study measured GH pulsatility and IGF-I levels in healthy men after a single injection of CJC-1295 at doses of 60 or 90 microg/kg. GH secretion increased, with a 7.5-fold increase in basal GH levels and a 46% increase in mean GH levels. IGF-I levels also increased by 45% after treatment.
Abstract
<h4>Context</h4>Pulsatile GH secretion is considered important for many of the hormone's physiological effects. Short-term GHRH infusions enhance GH pulsatility and increase IGF-I, but the short GHRH half-life limits its therapeutic use. A synthetic GHRH analog (CJC-1295) that binds permanently to endogenous albumin after injection (half-life = 8 d) stimulates GH and IGF-I secretion in several animal species and in normal human subjects and enhances growth in rats.<h4>Objective</h4>Our objective was to assess GH pulsatility after a single injection of CJC-1295 and determine which GH secretion parameters correlated to the increase in IGF-I production.<h4>Methods</h4>GH pulsatility was assessed by 20-min blood sampling during an overnight 12-h period in healthy 20- to 40-yr-old men before and 1 wk after injection of either 60 or 90 microg/kg CJC-1295.<h4>Results</h4>GH secretion was increased after CJC-1295 administration with preserved pulsatility. The frequency and magnitude of GH secretory pulses were unaltered. However, basal (trough) GH levels were markedly increased (7.5-fold; P < 0.0001) and contributed to an overall increase in GH secretion (mean GH levels, 46%; P < 0.01) and IGF-I levels (45%; P < 0.001). No significant differences were observed between the responses to the two drug doses. The IGF-I increases did not correlate with any parameters of GH secretion.<h4>Conclusions</h4>CJC-1295 increased trough and mean GH secretion and IGF-I production with preserved GH pulsatility. The marked enhancement of trough GH levels by continuous GHRH stimulation implicates the importance of this effect on increasing IGF-I. Long-acting GHRH preparations may have clinical utility in patients with intact pituitary GH secretory capability.
Background
Not reported in abstract.
Methods
Not reported in abstract.
Results
Not reported in abstract.
Interpretation
Not reported in abstract.
Limitations
Not reported in abstract.