Effects of peptide T derivatives on the proliferation of cultured human keratinocytes.
Marastoni. M M; Scaranari. V V; Fantini. F F; Sevignani. C C; Tomatis. R R
Key Findings
- Linear peptide T (both D‑Ala1‑modified and the plain hexapeptide) increased human keratinocyte proliferation at 0.1 µM.
- The cyclic analog of peptide T (CPT) showed no effect on cell growth.
- A VIP receptor antagonist blocked VIP‑induced growth but did not interfere with peptide T‑induced growth, implying distinct receptors.
Practical Outcomes
- For biohackers interested in skin health or wound healing, linear forms of peptide T may have modest skin‑cell‑boosting properties, whereas the cyclic version likely won’t help. The results suggest that peptide T works via a different mechanism than VIP, so combining them might be additive, but more human data are needed before any dosing protocol can be recommended.
Summary
The study tested three versions of peptide T and a related peptide (VIP) on human skin cells grown in the lab. Two forms of peptide T and VIP each boosted cell growth, while a cyclic version of peptide T did not. Blocking VIP's receptor stopped VIP's effect but didn’t affect peptide T, suggesting they work through different pathways.
Abstract
[D-Ala1]peptideT-amide, the linear hexapeptide H-Thr-Hse-Asn-Tyr-Thr-Asp-OH (LPT) and its cyclic analog, cyclo(-Thr-Hse-Asn-Tyr-Thr-Asp-) (CPT), were tested for their effects on the proliferation of cultured normal human keratinocytes (KTs) in comparison with vasoactive intestinal peptide (VIP). [D-Ala1]PT-NH2, LPT and VIP (all 0.1 mumol/l) increased the cell number in KT cultures, whereas CPT was ineffective. The VIP antagonist [N-Ac-Tyr1,D-Phe2]GRF (1-29)-NH2 significantly inhibited the VIP effects on KTs. On the other hand this antagonist did not affect the peptide T (PT) compounds-induced stimulation of KTs, providing indirect evidence that the mitogenic effects of VIP and PT peptides are probably mediated via different receptors.
Study Information
pubmed
1995