Peptide family · 6 members
Small humanin-like peptides (SHLP1–SHLP6)
Six small humanin-like peptides are encoded in the same region of mitochondrial DNA as humanin, the 16S ribosomal RNA gene. An in silico search found them, and the 2016 paper that named them reported that they differ in how they affect cell survival in culture [1].
Two have their own entries, SHLP2 and SHLP6. The other four are known almost entirely from that first paper, so their notes live here; their former pages now redirect to this one. None is an approved medicine, and none has been given to people in a published trial.
SHLP1
Merged into this page, October 2026
Found in the 2016 screen of the humanin region [1]. Beyond that paper's comparison of the six peptides' effects on cell viability, no study this site has read characterises SHLP1 on its own, so no sequence, mass or activity is stated for it here.
SHLP2
The most studied of the six. In the 2016 paper it reduced apoptosis and reactive oxygen species and improved mitochondrial metabolism in cells, enhanced pre-adipocyte differentiation, and, infused into the brain during clamp studies, increased glucose uptake and suppressed hepatic glucose production, which the authors read as insulin sensitising. Like humanin, its circulating level fell with age [1].
SHLP3
Merged into this page, October 2026
Studied alongside SHLP2 because the two shared humanin's protective effects: in cells SHLP3 reduced apoptosis and the generation of reactive oxygen species, improved mitochondrial metabolism and enhanced pre-adipocyte differentiation [1]. The brain-infusion and ageing findings were reported for SHLP2, not SHLP3.
SHLP4
Merged into this page, October 2026
Found in the 2016 screen [1]. No study this site has read characterises SHLP4 beyond that paper's cell-viability comparison; earlier claims here about proliferation and insulin sensitivity had no source and were removed.
SHLP5
Merged into this page, October 2026
Found in the 2016 screen [1]. No study this site has read characterises SHLP5 beyond that paper's cell-viability comparison; earlier claims here about metabolic regulation and stress protection had no source and were removed.
SHLP6
Found in the same screen [1]; its own entry covers the studies that followed.
Related
Sources
- Cobb LJ, et al. "Naturally occurring mitochondrial-derived peptides are age-dependent regulators of apoptosis, insulin sensitivity, and inflammatory markers." Aging (Albany NY), 2016;8(4):796-809. PMID: 27070352.
- Yen K, et al. "The mitochondrial derived peptide humanin is a regulator of lifespan and healthspan." Aging (Albany NY), 2020;12(12):11185-11199. PMID: 32575074.