[Modulation of the circadian rhythm of the glucocorticoid hormone level in mice by thymoptin administration at various times of day].
Shurlygina. A V AV; Letiagin. A Iu AIu; Chesnokova. V M VM; Trufakin. V A VA
Key Findings
- Thymopthin (1% thymosin‑alpha‑1) administered twice daily alters the circadian rhythm of corticosterone in mice.
- A morning injection increases overall daily corticosterone levels; an evening injection decreases them relative to control.
- The effect was observed using a low dose (0.05 mg per mouse) and measured by plasma hormone binding assays.
Practical Outcomes
- For biohackers, the study hints that when you take thymosin‑alpha‑1 could matter for stress‑hormone regulation. If you aim to boost cortisol in the morning (e.g., for alertness) or dampen it at night (e.g., for better sleep), timing the dose accordingly might be useful. However, the data are from mice, so human dosing and safety need careful validation before applying these protocols.
Summary
Giving thymosin‑alpha‑1 (as part of a drug called thymopthin) to mice changes the daily pattern of their stress hormone corticosterone. A morning dose raises the hormone level, while an evening dose lowers it compared to mice that got just saline. This shows that the timing of thymic hormone administration can shift the body's natural hormone rhythm.
Abstract
A study was made of the level of corticosterone in mouse blood plasma after 4-time daily administration of thymopthin (a drug containing 1% of thymosin-alpha 1, synthesized in the All-Union Research Institute of Technology of Blood Substitution and Hormonal Drugs) at a doze of 0.05 mg per mouse in the morning and evening. The object of investigation was blood plasma of CBA male mice aged 12-16 weeks. The investigation was experimental. The purpose was to elucidate a possible role of thymic hormones in the regulation of circadian rhythm of glucocorticoid function of the adrenal cortex. Plasma concentration of corticosterone was determined by concurrent protein binding of hormones. Thymopthin administration was shown to result in change of circadian rhythm of the level of corticosteroids in mouse plasma. Drug administration in the morning elevated daily concentration of corticosterone, that also evening reduced it as compared to the control group that in the received the same volume of physiological salt solution. A curve of the daily time course was obtained as a result of smoothing by a method of the least squares. These results should be taken into account when using thymic drugs for therapeutic and experimental purposes.
Study Information
pubmed
1991