Argireline vs. Thymalin

Category

Cosmetic

Healing

CAS no.

616204-22-9

63958-90-7

Molecular weight

888.99 g/mol

1000 g/mol

Half-life

0.5 h

Sequence

Argireline

Argireline is a synthetic hexapeptide whose sequence corresponds to the N-terminus of the SNAP-25 protein. In vitro it has been shown to competitively inhibit SNARE complex formation (necessary for vesicle fusion in neurotransmitter release). Topical application is intended — given very limited skin permeation — to attenuate cholinergic signalling at the neuromuscular endplate. The effect is orders of magnitude weaker than intramuscular botulinum toxin; the clinical translatability of the in-vitro observations to the skin microenvironment is contested.

Thymalin

Thymalin is a complex of multiple polypeptides extracted from bovine or calf thymus. Postulated mechanisms include modulation of T-lymphocyte maturation, influence on interleukin profiles and stimulation of cellular immune response. Being a multi-component preparation, individual mechanisms are difficult to disentangle. Khavinson and colleagues from St Petersburg have described the mechanism over decades in Russian publications.

Highest evidence

Studies

3

4

of which in humans

2

2

Effects recorded

3

3

Open conflicts

1

1

Documented adverse events

1

1