Thymulin
Zinc-Dependent Thymic Nonapeptide | Immune Modulation & Anti-Inflammatory
Thymulin (also known as Serum Thymic Factor or FTS - Facteur Thymique Sérique) is a 9-amino acid metallopeptide hormone produced exclusively by thymic epithelial cells. First characterized by Bach and colleagues in 1977, thymulin is unique in requiring zinc binding (1:1 equimolecular ratio) for biological activity. The zinc-thymulin complex adopts a specific three-dimensional conformation essential for its immunomodulatory functions, including T-cell differentiation, NK cell enhancement, and suppressor T-cell regulation. Beyond immune functions, thymulin demonstrates potent anti-inflammatory and analgesic properties through inhibition of NF-κB, p38 MAPK, and pro-inflammatory cytokines. Serum thymulin levels decline progressively with age (peaking in pre-adolescence), contributing to immunosenescence. Research shows promise in lung diseases, neuropathic pain, and age-related immune dysfunction, though human clinical trials remain limited.
Daily dose
1-5 mg (anecdotal human protocols)
Frequency
Once daily during cycle
Cycle length
5-10 days
Storage
-20°C (lyophilized)
Key benefits
Immune modulation, T-cell differentiation, anti-inflammatory effects, potential analgesic properties
How it works
Zinc-dependent metallopeptide that induces T-cell differentiation, enhances suppressor T-cells and NK cells, and inhibits pro-inflammatory cytokines via NF-κB and p38 MAPK suppression.
Dosage protocols
Goal
Immune Support (Anecdotal)
Dose
1-5 mg · Once daily
Route
SubQ
Goal
Animal Research
Dose
15 μg/100g body weight · Per protocol
Route
IP or SubQ
Research indications
immunity
inflammation
anti Aging
Administration
Interactions
Safety notes
Requires zinc for biological activity
Very short serum half-life (~10 min)
No toxicity in preclinical studies
Limited human data -research only
Not FDA approved
Research studies
Potent Analgesic and Anti-inflammatory Actions of PAT in the Rat (2002)
Rat | PAT analog | 1-200 μg IP | Endotoxin inflammation model
Thymulin analog PAT (25-50 μg) abolished increased TNF-α and significantly reduced IL-1β, IL-6, and NGF levels. Demonstrated comparable or stronger analgesic effects than indomethacin and dexamethasone without affecting normal physiological parameters.
View study →Thymulin Treatment Attenuates Inflammatory Pain via Spinal Mechanisms (2019)
Rat | Thymulin IP | 21 days | CFA-induced inflammation
Thymulin notably reduced thermal hyperalgesia and paw edema. Molecular analysis showed reduced microglial activation, p38 MAPK phosphorylation, and spinal pro-inflammatory cytokines (TNF-α, IL-6). Long-term treatment effective for neuroinflammation.
View study →Immunomodulatory Role of Thymulin in Lung Diseases (2010)
Review | Multiple models | Lung disease applications
Comprehensive review showing thymulin has consistent beneficial effects in experimental lung disease models. Broad inhibitory effect on pro-inflammatory cytokines, suppresses p38 (implicated in glucocorticoid resistance), and inhibits NF-κB. No toxicity even at high doses -good candidate for gene therapy.
View study →Interactions Between Zinc and Thymulin (1994)
Review | Zinc biology | CNRS Paris
Established that thymulin requires equimolar zinc for activity. Serum thymulin activity serves as sensitive indicator of zinc deficiency. Zinc supplementation restores thymulin activity both in vivo and in vitro. Thymic epithelial cells secrete thymulin in active zinc-bound form.
View study →PAT Inhibits Neuropathic Pain via α7-nAChR Potentiation (2013)
Rat | PAT analog | Electrophysiology | Neuropathy models
Demonstrated that thymulin analog PAT mediates anti-inflammatory action partly through potentiating α7-nicotinic acetylcholine receptors. Equal or stronger inhibitory effects on neuropathic manifestations compared to morphine or meloxicam.
View study →