cAMP dependent and independent regulation of thyroglobulin synthesis by two clones of the OVNIS 6H thyroid cell line.
Aouani. A A; Hovsépian. S S; Fayet. G G
Key Findings
- Insulin and hydrocortisone stimulate thyroglobulin synthesis via cAMP‑independent pathways.
- TSH only stimulates thyroglobulin when combined with insulin (or insulin + hydrocortisone) and does so through cAMP.
- The peptide glycyl‑histidyl‑lysine (GHK) showed no effect on thyroglobulin synthesis or cAMP levels.
- Forskolin mimics TSH by raising cAMP and thyroglobulin output; calf serum suppresses both.
Practical Outcomes
- For most biohackers, this study offers little direct guidance. It suggests that taking GHK‑Cu is unlikely to influence thyroid hormone production via these pathways, and that insulin‑like or glucocorticoid‑like interventions would be needed to affect thyroid protein synthesis. No actionable dosing or protocol changes are derived from these findings.
Summary
In thyroid cells, insulin and hydrocortisone can boost production of thyroglobulin (a key thyroid protein) without using the usual cAMP signaling, while TSH needs cAMP to work. The peptide GHK (the building block of GHK‑Cu) did not affect thyroglobulin production at all.
Abstract
The hormonal regulation of thyroglobulin synthesis has been studied using two independent clones of the OVNIS 6H cell line. Insulin, hydrocortisone and TSH were able to stimulate thyroglobulin synthesis, whereas transferrin, somatostatin and glycyl-histidyl-lysine were without effect. Insulin stimulated thyroglobulin synthesis without affecting cAMP production. Hydrocortisone, when combined with insulin was a stimulator too; this stimulation was not accompanied by an increase in cAMP. TSH alone was unable to stimulate either cAMP or thyroglobulin synthesis. The stimulatory effect of TSH on thyroglobulin synthesis took place only when combined with insulin or insulin plus hydrocortisone, and was mediated by cAMP. Consequently, insulin and hydrocortisone stimulated thyroglobulin synthesis by cAMP-independent mechanisms, whereas TSH acted via the cAMP system. Forskolin mimicked TSH effects on cAMP and thyroglobulin synthesis. Calf serum inhibited cAMP and thyroglobulin production. Optimal cAMP and thyroglobulin synthesis as well as TSH responsiveness were obtained in serum-free medium supplemented with 5 micrograms/ml insulin, 100 nM hydrocortisone and 1 mU/ml TSH.
Study Information
pubmed
1987
1987-07-01T00:00:00.000Z
10.1016/0303-7207(87)90108-0
23
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