Humanin

Humanin (HN) was identified in 2001 by Yoshiko Hashimoto and colleagues at Keio University School of Medicine, published in the Proceedings of the National Academy of Sciences (PMID 11371646). The researchers were screening a cDNA library derived from surviving neurons in the occipital lobe of an Alzheimer's disease patient, searching for genes capable of rescuing neurons from death induced by a wide spectrum of familial Alzheimer's disease gene mutations and by neurotoxic amyloid-beta (Aβ) peptide. Humanin emerged from that screen as a 24-amino-acid peptide with the sequence MAPRGFSCLLLLTSEIDLPVKRRA, molecular formula C119H204N34O32S2, an average molecular weight of approximately 2,687.2 Daltons (PubChem CID 16131438, CAS 330936-69-1).

At Verified Peptides, we consider Humanin's discovery story genuinely unusual among the research peptides in our catalog: rather than being encoded by a conventional nuclear gene, Humanin is translated from a short open reading frame located within the MT-RNR2 gene — the same mitochondrial DNA region that encodes the mitochondrial 16S ribosomal RNA — using a non-canonical reading frame that was, at the time, entirely unexpected. This made Humanin the founding member of an entire class now called mitochondrial-derived peptides (MDPs), a family that has since expanded to include MOTS-c and six small humanin-like peptides (SHLP1 through SHLP6), all similarly hidden within mitochondrial DNA regions previously assumed to encode only ribosomal RNA or transfer RNA.

A further nuance that researchers should understand when evaluating the literature: in addition to the mitochondrial copy of the Humanin-coding sequence, the human nuclear genome carries roughly a dozen or more Humanin-like sequence copies scattered across different chromosomes, apparently generated by historical transfer of mitochondrial DNA fragments into the nuclear genome over evolutionary time. Whether any of these nuclear copies are actively transcribed and translated into functional peptide, and how their output might relate to mitochondrially-derived Humanin, remains an active area of investigation rather than settled science. The rat homolog of Humanin, discovered subsequently, is referred to in the literature as "rattin."

At Verified Peptides, we think it's important for researchers to understand exactly how far the Humanin evidence base has progressed, because the compound has a genuinely striking discovery story but, as of this writing in 2026, no completed and published human clinical trial. The foundational 2001 PNAS paper (Hashimoto et al., PMID 11371646) demonstrated that Humanin peptide rescued cultured neurons from death induced by a wide spectrum of familial Alzheimer's disease gene mutations — including mutant forms of presenilin-1, presenilin-2, and amyloid precursor protein — as well as from direct exposure to neurotoxic amyloid-beta. A companion mechanistic paper published the same year in Biochemical and Biophysical Research Communications extended these findings using a Swedish-mutant APP model.

The IGFBP-3 interaction paper (Ikonen et al., 2003, PNAS, PMID 14561895) established a second, independent cytoprotective mechanism and has been cited extensively in subsequent work examining how the IGF axis intersects with apoptotic regulation in aging and neurodegenerative disease research. Building on the anti-apoptotic and IGFBP-3 findings, a substantial preclinical literature has since emerged studying Humanin and its synthetic analogs — most notably HNG (a glycine-14 substituted analog with substantially greater potency than native Humanin) — across several disease-relevant rodent models.

In aging-mouse research, chronic HNG treatment of aged female mice over a 14-month period was reported to prevent age-related myocardial fibrosis, and separately, HNG-treated aging mice showed better balance and coordination than untreated controls, suggesting effects extending across the nervous system rather than being confined to a single organ system. In metabolic research, Humanin has been studied for effects on insulin sensitivity and beta-cell survival; the HNG analog increased glucose-stimulated insulin secretion in islets isolated from db/db mice (a type 2 diabetes model), and native Humanin treatment over a 20-week period was reported to significantly delay the onset of diabetes in non-obese diabetic (NOD) mice, a model of autoimmune type 1 diabetes.

On the human side, the evidence remains observational rather than interventional: several epidemiological studies have reported that lower circulating Humanin levels correlate with higher Alzheimer's disease risk and with markers of aging, which is consistent with — but does not prove — a causal protective role for the endogenous peptide. We want to be direct about this distinction: no completed, published human interventional trial has demonstrated that administering exogenous Humanin or any Humanin analog prevents, slows, or treats Alzheimer's disease, cardiovascular disease, or diabetes in humans. The compound's research profile, as of 2026, remains preclinical and mechanistic rather than clinically validated. At Verified Peptides, we sell research-grade Humanin exclusively for laboratory research, not for human or animal treatment.

Humanin's discovery fundamentally changed how researchers think about the mitochondrial genome. Before 2001, the 37 genes encoded in human mitochondrial DNA were considered a settled inventory — 13 proteins involved in oxidative phosphorylation, plus the RNA components (22 tRNAs and 2 rRNAs) needed to translate them inside the mitochondrion. Humanin's discovery, hidden in an alternative reading frame within what was assumed to be purely ribosomal-RNA-coding sequence, was the first evidence that mitochondrial DNA could encode additional, biologically active peptides beyond that established inventory — opening an entirely new research field now encompassing MOTS-c and the six SHLPs.

A genuinely unresolved nuance in the literature involves the human nuclear genome's own collection of Humanin-like sequences. Because mitochondrial DNA fragments have been inserted into the nuclear genome at multiple points across evolutionary history (a phenomenon called NUMT insertion, for "nuclear mitochondrial DNA"), the human nuclear genome contains more than a dozen sequences closely resembling the mitochondrial Humanin-coding region. Whether these nuclear copies are ever actually transcribed and translated into functional Humanin-like peptide — and if so, under what conditions — remains actively studied rather than definitively resolved, meaning some of the biological Humanin activity reported in various tissues could, in principle, originate from a nuclear-encoded source rather than exclusively the mitochondrial gene.

Humanin has also been detected in human cerebrospinal fluid and across a wide range of tissues beyond the brain, including testis (the tissue in which the Ikonen IGFBP-3 interaction was confirmed via co-immunoprecipitation), reflecting its role as a broadly expressed mitochondrial signal rather than a brain-restricted molecule. Researchers have additionally reported detecting Humanin within atherosclerotic plaque tissue in human carotid arteries, a finding that has fed into cardiovascular-focused research interest in the peptide separate from its original neuroprotective discovery context.

Because native Humanin has a relatively short half-life and modest potency in some assay systems, much of the more recent preclinical research — including the aging-mouse cardioprotection and diabetes-prevention studies — has actually been conducted using engineered analogs such as HNG (glycine-14 substituted) rather than the native 24-mer sequence, an important distinction for researchers comparing results across different published studies.

At Verified Peptides, we require independent third-party HPLC (high-performance liquid chromatography) purity testing and mass spectrometry identity confirmation for every batch of research-grade Humanin we offer, with a Certificate of Analysis (COA) available for each lot. As a 24-residue peptide synthesized via standard solid-phase peptide synthesis, Humanin's production is well within established peptide-manufacturing capability, but batch-to-batch purity verification remains essential for any research relying on consistent, reproducible results.

We source exclusively from manufacturers operating under Good Manufacturing Practice (GMP)-aligned quality systems, and every lot is independently verified before being offered for sale — we do not rely solely on a supplier's own internal testing documentation. Researchers should always request and review the specific COA for the lot they receive, checking confirmed purity percentage, verified molecular identity via mass spectrometry, and endotoxin or microbial testing where applicable.

Because so much of the published Humanin literature uses engineered analogs such as HNG rather than the native sequence, researchers should pay particular attention to confirming exactly which sequence variant — native Humanin versus a specific analog — they are receiving, since results from native-sequence studies and analog studies are not necessarily directly comparable.

Lyophilized (freeze-dried) Humanin is stable when stored at -20°C, protected from light and moisture, and researchers can generally expect the unreconstituted peptide to maintain integrity over an extended period under these conditions. At Verified Peptides, we ship lyophilized peptide with appropriate cold-chain packaging to preserve stability in transit.

Once reconstituted with bacteriostatic water or another appropriate sterile diluent, Humanin solution should be stored refrigerated at 2–8°C and used within the timeframe indicated on the product's documentation. Reconstituted peptide solutions are generally less stable than the lyophilized form and are more susceptible to degradation and microbial contamination with repeated freeze-thaw cycling, so researchers should avoid repeated freeze-thaw cycles and aliquot solutions where practical to limit how many times any single vial is thawed.

As with other peptides of similar size and composition, exposure to excessive heat, direct light, or extended room-temperature storage accelerates degradation and can compromise the structural integrity relevant to research applications. Following the specific storage guidance provided with each lot's documentation remains the most reliable way to preserve a sample's research validity.