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Thymulin

Well Studied

FTS | Zinc-Dependent Thymic Nonapeptide

Dose 1-10mcg per injection (research protocols)
Frequency Daily during research protocols
Cycle Varies by research protocol
Storage Reconstituted: 2-8°C, use within 4 weeks

Thymulin is a nonapeptide hormone exclusively secreted by thymic epithelial cells, discovered by Jean-François Bach in the 1970s. Unlike thymalin (a peptide extract mixture), thymulin is a single, defined 9-amino-acid peptide that requires zinc binding for biological activity. It plays a crucial role in T-cell differentiation and maturation within the thymus. Serum thymulin levels decline significantly with age and zinc deficiency, contributing to age-related immune decline (immunosenescence). Research has explored thymulin's potential in restoring immune function, managing autoimmune conditions, and as an anti-inflammatory agent.

Mechanism of Action

Thymulin exerts its effects through binding to high-affinity receptors on T-lymphocytes and other immune cells. The zinc-thymulin complex is the biologically active form - without zinc, the peptide has no immunological activity. Thymulin promotes: (1) differentiation of immature T-cells into mature T-cell subsets, (2) modulation of cytokine release including IL-2 and interferon-gamma, (3) regulation of T-helper and T-suppressor cell balance, (4) enhancement of NK cell activity, and (5) anti-inflammatory effects through suppression of pro-inflammatory mediators. It also has neuroendocrine effects, influencing the hypothalamic-pituitary-adrenal axis.

Key Benefits

  • Essential for T-cell maturation and differentiation
  • Modulates immune responses (immunomodulatory)
  • Anti-inflammatory properties
  • Declines with age - restoration may combat immunosenescence
  • Well-defined single peptide (unlike extracts)
  • Studied in autoimmune disease research
  • Neuroendocrine regulatory effects
  • Zinc-dependent activity allows for regulation
Molecular Weight
857 Da (peptide), 921 Da (with zinc)
Chain Length
9 amino acids
Type
Thymic nonapeptide hormone
Amino Acid Sequence
One-letter: ?AKSQGGS???
H₂N
H
? 1
O C
N
A 2
O C
N
K 3
O C
N
S 4
O C
N
Q 5
O C
N
H
G 6
O C
N
H
G 7
O C
N
S 8
O C
N
H
? 9
O C
N
H
? 10
O C
N
H
? 11
COOH
pGl
1

pGlu

Position 1

Ala
2

Alanine

Position 2

Lys
3

Lysine

Position 3

Ser
4

Serine

Position 4

Gln
5

Glutamine

Position 5

Gly
6

Glycine

Position 6

Gly
7

Glycine

Position 7

Ser
8

Serine

Position 8

Asn
9

Asn (pyro

Position 9

Glu
10

Glu N

Position 10

ter
11

terminus)

Position 11

N-terminus C-terminus
Hydrophobic
Polar
Positive (+)
Negative (-)
Modified

Immune System Research

  • Immunosenescence

    Age-related decline in thymulin correlates with reduced immune function; supplementation may restore T-cell parameters.

  • T-Cell Deficiency

    Promotes differentiation and maturation of T-lymphocytes in thymus.

  • Zinc Deficiency States

    Thymulin activity depends on zinc; studied in zinc-depleted conditions.

Inflammatory & Autoimmune Research

  • Anti-Inflammatory Effects

    Research shows thymulin suppresses pro-inflammatory cytokines and mediators.

  • Autoimmune Conditions

    Investigated for potential to restore immune balance in autoimmune states.

  • Type 1 Diabetes Research

    Studied for effects on pancreatic beta cells and immune modulation in diabetes models.

Neuroendocrine Research

  • HPA Axis Modulation

    Thymulin influences hypothalamic-pituitary-adrenal axis function.

  • Neuroprotection

    Some research suggests protective effects on neural tissue.

Thymulin is typically administered via subcutaneous or intraperitoneal injection in research settings. As a small peptide, it can also be explored via intranasal delivery for CNS effects. Zinc status should be adequate for biological activity.

GoalDoseFrequencyRoute
Research protocol (immune)1-10 mcgDailySubQ
Intranasal (experimental)VariableAs studiedIntranasal

Reconstitution Instructions

Materials Needed:
  • Bacteriostatic water
  • Insulin syringes
  • Alcohol swabs
  • Sterile vial
  1. 1 Ensure adequate zinc supplementation for activity
  2. 2 Reconstitute with bacteriostatic water
  3. 3 Inject water slowly down vial wall
  4. 4 Gently swirl until dissolved
  5. 5 Store refrigerated at 2-8°C
  6. 6 Use within 4 weeks of reconstitution
Zinc supplementation

Essential - thymulin requires zinc for biological activity. Ensure adequate zinc status.

synergistic
Thymosin Alpha-1

Different thymic peptides with complementary mechanisms.

compatible
Thymalin

Thymalin is a peptide mixture while thymulin is a single defined peptide; can complement each other.

compatible
Epitalon

Different mechanisms; no known negative interactions.

compatible
BPC-157

Different mechanisms; no known interactions.

compatible
Hours

Receptor binding and initial cellular signaling

Days 1-7

Immune cell modulation begins; cytokine profile changes

Weeks 2-4

T-cell differentiation effects; measurable immune parameters

Months

Long-term immune restoration in research models

Common Side Effects

  • Generally well-tolerated in research
  • Injection site reactions (mild)

Stop Signs - Discontinue if:

  • Signs of allergic reaction
  • Unexpected immune changes

Contraindications

  • Autoimmune diseases (use with medical supervision)
  • Organ transplant recipients on immunosuppression
  • Pregnancy or breastfeeding
  • Known hypersensitivity to thymic peptides

Good Signs

  • White lyophilized powder
  • Clear solution after reconstitution
  • Intact vacuum seal
  • Certificate of analysis with sequence verification

Warning Signs

  • Slight clumping that dissolves easily

Bad Signs

  • Discolored powder
  • Cloudy solution after reconstitution
  • Particulates present
  • Broken seal
  • Thymulin (FTS) - A Thymic Hormone
    Bach JF, Dardenne M
    Clinics in Immunology and Immunopathology (1989)

    Comprehensive review of thymulin discovery, structure, and immunological functions.

  • The neuroendocrine role of thymulin
    Journal of Neuroimmunology (2000)

    Thymulin modulates hypothalamic-pituitary-adrenal axis and has neuroendocrine effects beyond immunity.

  • Zinc and thymulin
    Advances in Experimental Medicine and Biology

    Zinc is essential for thymulin biological activity; zinc deficiency causes functional thymulin deficiency.

  • Thymulin and aging
    Mechanisms of Ageing and Development

    Serum thymulin levels decline dramatically with age, correlating with immunosenescence and increased infection susceptibility.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.