Effect of growth hormone-releasing hormone (GHRH) and GHRH antagonist (MZ-4-71) on interferon-gamma secretion from human peripheral blood mononuclear cells in vitro.
Siejka. A A; Ławnicka. H H; Komorowski. J J; Stepień. T T; Krupiński. R R; Stepień. H H
Key Findings
- Synthetic GHRH (1‑44)NH2 increased IFN‑gamma secretion from human PBMCs at concentrations from 10⁻¹⁰ to 10⁻⁶ M.
- The GHRH antagonist MZ‑4‑71 reduced IFN‑gamma secretion in a dose‑dependent way, with significant drops at 10⁻⁸ M and 10⁻⁶ M.
- Both effects were observed in vitro, indicating a direct immunomodulatory role for GHRH independent of growth hormone release.
Practical Outcomes
- For biohackers using sermorelin (a GHRH analog), this suggests the peptide might boost certain immune functions, but the evidence is limited to cell cultures and does not translate directly to dosing or health outcomes in people. Until human studies confirm the effect, treat any immune‑boosting claims with caution and monitor for unexpected immune changes when experimenting with GHRH‑based protocols.
Summary
In a lab test, the natural hormone that tells the pituitary to release growth hormone (GHRH) made immune cells release more of the signaling molecule IFN‑gamma, while a drug that blocks GHRH did the opposite. This shows GHRH can directly affect immune activity, at least in a dish.
Abstract
Numerous reports indicate close interactions between the neuroendocrine and the immune systems. Hypothalamic neuropeptide, growth hormone-releasing hormone (GHRH) stimulates growth hormone (GH) secretion from the anterior pituitary gland, but recently some immunomodulatory properties of this peptide have also been demonstrated. In the present studies we evaluated the effect of human synthetic GHRH(1-44)NH(2) and GHRH antagonist (MZ-4-71) on interferon (IFN)-gamma secretion from human peripheral blood mononuclear cells (PBMC). GHRH(1-44)NH(2) at 10(-10), 10(-8) and 10(-6) M concentrations significantly (p < 0.05) increased the IFN-gamma level in supernatants of cultured cells, as compared with the controls. GHRH antagonist (MZ-4-71) at 10(-10), 10(-8) and 10(-6) M concentrations diminished the IFN-gamma level in supernatants in a dose-dependent manner, but statistically significant differences were observed only at 10(-8) M and 10(-6) M (p < 0.05 vs controls). Our results demonstrate that GHRH and GHRH antagonist MZ-4-71 can modulate IFN-gamma secretion in vitro by human peripheral blood mononuclear cells.
Study Information
pubmed
2004
2004-02-01T00:00:00.000Z
10.1016/j.npep.2003.12.001
7
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