Humanin

Humanin (Mitochondria-Derived Peptide)

Evidence & Status

  • Preliminary / Experimental
  • Preliminary

At a Glance

A small peptide encoded within the mitochondrial genome, originally discovered in research on familial Alzheimer's disease resistance. Studied for neuroprotective and cytoprotective properties, with circulating levels observed to decline significantly with age.

Plain English

Researchers study Humanin because it was discovered when scientists investigated why certain individuals appeared genetically protected from Alzheimer's disease. Unusually, it is encoded within the mitochondrial genome rather than the cell's main nucleus. Scientists are interested in its ability to protect neurons and other cells from dying under stressful conditions, and in how its age-related decline might contribute to increased vulnerability to neurodegeneration and metabolic disease. It is closely related to MOTS-c, another mitochondria-encoded peptide in this database, and together they represent an emerging field of mitochondria-derived peptide biology.

Overview

The first mitochondria-derived peptide (MDP) discovered, encoded in the 16S ribosomal RNA gene of the mitochondrial genome. Acts as an endogenous neuroprotective factor that blocks Alzheimer's amyloid-beta toxicity, ischemic neuronal death, and cellular apoptosis via multiple receptors in cellular and animal models. Circulating endogenous humanin levels decline with age and correlate inversely with IGF-1 signaling; higher circulating levels have been observed in offspring of centenarians in human observational studies. Humanin G (HNG, S14G substitution) is reported in preclinical models to have substantially greater potency. No interventional human trials of exogenous humanin or HNG administration have been published. Studied preclinically for neuroprotection, insulin sensitization, and cardiovascular protection.

Research Summary

Humanin was discovered in 2001 (Hashimoto et al., PNAS) as an endogenous neuroprotective peptide encoded in mitochondrial DNA. The discovery paper demonstrated that humanin blocks neuronal cell death induced by a wide spectrum of familial Alzheimer's disease genes and amyloid-beta in cellular models — all evidence from this foundational work is preclinical and cellular. Endogenous circulating humanin levels have been studied in human observational research: published data report associations with longevity biomarkers and centenarian offspring, and inverse correlations with IGF-1 signaling. These observations concern endogenous, naturally produced humanin and do not constitute evidence that administration of exogenous humanin extends human lifespan. No interventional human trials of administered humanin or HNG have been published. Animal and cellular models demonstrate neuroprotective, insulin-sensitizing, and cardioprotective effects, all preclinical. The previously stored PubMed identifiers (PMID 22582017 and PMID 11721048) were confirmed as catastrophic entity mismatches and have been removed. Evidence remains preliminary.

Research Areas

  • Neurodegeneration & Alzheimer's disease
  • Longevity & centenarian biology
  • Insulin sensitization
  • Anti-apoptosis
  • Cardiovascular protection
  • IGF-1 modulation

Safety & Risks

Serious Risks

  • Very limited human safety data; broad anti-apoptotic effects raise theoretical considerations regarding cancer biology; insufficient evidence to establish safety profile

Reported Side Effects

  • Mild injection site reactions
  • Generally very well-tolerated in animal and preliminary human data
United States
Research only
United Kingdom
Research only
Australia
Research only
Canada
Research only

Citations & Sources