Every Peptide

Peptide field guide

MK-12

A 12-amino-acid midkine-derived peptide (KARYNAQCQETI) studied as a potential vital pulp therapy agent to promote reparative dentine formation.

Evidence: emerging Safety: unknown Status: research Updated: March 24, 2026 DentistryRegenerationPreclinical

What it is

MK‑12 is a 12‑amino‑acid peptide derived from the human midkine (MK) protein sequence.

Sequence (reported): KARYNAQCQETI.

In the initial paper that introduced MK‑12 as a candidate, it was selected from a panel of midkine fragments based on mineralization/odontogenic differentiation screening.

Why people care

The motivating clinical use case is vital pulp therapy (VPT), including pulp capping, where a material is placed to protect exposed pulp and encourage formation of reparative dentine.

Using short peptides instead of full-length recombinant proteins is attractive because peptides can be:

  • easier to manufacture consistently
  • simpler to formulate into biomaterials
  • potentially cheaper

That said, “easier to make” does not automatically translate into “works in humans.”

Evidence landscape

As of March 2026, evidence we’ve indexed for MK‑12 is preclinical:

  • in vitro assays in dental pulp-related cell systems
  • an in vivo rat pulp capping model

Latest updates

  • 2026-03-25: A paper in International Endodontic Journal reports that MK‑12 promoted reparative dentine formation in rats and was associated with DDIT4/mTOR pathway changes and autophagy signaling in mechanistic experiments.

Safety reality

There is no established human safety database for MK‑12 as a therapeutic. Safety and feasibility will depend heavily on:

  • local delivery and formulation
  • dose and exposure duration
  • immune and off-target effects

References

  • Qiao S, et al. Novel Midkine‑Derived Peptide Promotes Reparative Dentine Formation via DDIT4/mTOR Pathway‑Mediated Activation of Autophagy. Int Endod J. (2026).