PMID-9360512 – Sermorelin GHRH Immune System Effects in Aging
Khorram O, Yeung M, Yen SS. Effects of [norleucine27]growth hormone-releasing hormone (GHRH) (1-29)-NH2 administration on the immune system of aging men and women. J Clin Endocrinol Metab. 1997;82(11):3590-3596.
Quick Reference
| Property | Value |
|---|---|
| PMID | 9360512 |
| DOI | 10.1210/jcem.82.11.4363 |
| Year | 1997 |
| Journal | Journal of Clinical Endocrinology & Metabolism |
| Study Type | RCT |
| Evidence Level | II |
| Sample | 19 men and women, ages 55-71 |
| Peptide(s) Studied | Sermorelin |
Key Findings
- GHRH(1-29) (sermorelin analog) administered at 10 mcg/kg SubQ nightly for 5 months
- Significant increase in NK cell number and cytolytic activity
- Increased production of IL-2 by peripheral blood mononuclear cells
- Total T-cell numbers increased, particularly CD4+ helper T cells
- B-cell numbers showed modest increases
- Thymic involution was not assessed but GH-mediated immune reconstitution was proposed
- No adverse immune effects (autoimmunity markers unchanged)
Study Design
Companion immunological study to PMID-9141536. Same cohort of 19 age-advanced adults (55-71 years) receiving GHRH(1-29) analog 10 mcg/kg SubQ nightly for 5 months. Immune parameters assessed before and after treatment.
Limitations
- Small sample size (n=19)
- Same sequential design limitation as companion study
- 5-month duration; durability of immune effects unknown
- No functional immune outcomes measured (infection rates, vaccine responses)
Clinical Relevance
Demonstrates that GHRH-stimulated GH secretion has immunomodulatory benefits in aging adults, supporting the concept that GH axis restoration may contribute to immune reconstitution. The increase in NK cell activity and IL-2 production is particularly relevant for age-related immune decline (immunosenescence). This provides a mechanistic rationale for including sermorelin in anti-aging protocols beyond body composition effects.
Related
#research #RCT #sermorelin #evidence-level-II