Normal Healthy Volunteers Clinical Trial
Official title:
Impact of Estradiol Addback on Somatostatin Rebound in Older Men
Repletion of testosterone (T) in older men drives Growth Hormone secretion after its aromatization to estradiol (E2) by potentiating endogenous GH drive.
Systemic concentrations of Te, E2, GH, Insulin-like Growth Factor-I and IGFBP-3 decline in healthy aging men. Relative sex-steroid deprivation accentuates GH and IGF-I depletion, since Te stimulates GH and IGF-I production in older men, hypogonadal males of all ages, and patients undergoing (genotypic female-to-male) gender reassignment. Tamoxifen blocks this effect of Te, suggesting involvement of E2 in GH's stimulation in men. E2 per se stimulates GH secretion in women. Because Te is converted to E2 by aromatization in the body, we postulate that E2 is the active moiety in men also. Moreover, we hypothesize that the decline of E2 in older men contributes to the fall in GH output. This has never been tested. From a clinical vantage, understanding the mechanistic basis of Te's drive of the somatotropic axis is especially relevant in boys with pubertal failure, adults with primary hypogonadism and men with aging-related hypoandrogenemia. In relation to aging in the male, testosterone and E2 bioavailabilities fall by 35-50% in the eighth compared with third decade of life. From a medical perspective, aging is accompanied by progressive osteopenia, sarcopenia and intra-abdominal obesity. These adverse outcomes are remediable by short-term replacement with Te and/or recombinant GH, thus linking GH/Te/E2 availability with key body-compositional features. ;
| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Completed |
NCT05019950 -
Safety Tolerability and Pharmacokinetics of Oral NIM-1324 in Healthy Adult Male and Female Volunteers
|
Phase 1 | |
| Completed |
NCT01366339 -
Tolerance and Pharmacokinetics Study of MNTX Tablets
|
Phase 1 | |
| Completed |
NCT01629446 -
Lofexidine Mass Balance in Volunteers
|
Phase 1 | |
| Completed |
NCT02026973 -
Impact of Endogenous E2 on SSI and GH Rebound
|
Phase 1 | |
| Completed |
NCT03860571 -
Safety, Tolerability, and Pharmacokinetics of Oral BT-11 in Healthy Adult Male and Female Volunteers
|
Phase 1 | |
| Recruiting |
NCT03234504 -
Development and Validation of a Novel Stereoacuity Test Using Head-mounted Display
|
||
| Completed |
NCT04188730 -
A Study Evaluating the Relative Bioavailability of Lofexidine Granules for Reconstitution Compared to LUCEMYRA (Lofexidine) Tablets and the Effect of Food on the Bioavailability of the Lofexidine Granules for Reconstitution
|
Phase 1 | |
| Completed |
NCT02271282 -
Estradiol-Receptor Blockade in Older Men and Women
|
Phase 1 | |
| Withdrawn |
NCT03291158 -
Safety and PK Trial Evaluating the Plasma, Epithelial Lining Fluid, and Alveolar Macrophage Concentrations of Minocin IV
|
Phase 1 | |
| Completed |
NCT02802631 -
Study to Evaluate Safety, Tolerability, and Pharmacokinetics of Minocin (Minocycline) for Injection in Healthy Adults
|
Phase 1 |