Twenty-four amino acids encoded inside mitochondrial DNA. Discovered by accident in 2001 while scientists were looking for something that could protect brain cells from Alzheimer's damage. And it is one of the first peptides ever shown to extend lifespan in animals by activating cellular cleanup.
🔑 Key Takeaways
- Humanin is a 24-amino-acid peptide encoded by the MT-RNR2 gene inside the mitochondrial DNA. Unlike most peptides that come from nuclear-encoded genes, Humanin originates in mitochondria and is the first mitochondrial-derived peptide (MDP) identified
- Discovered in 2001 by Dr. Yuichi Hashimoto in Dr. Ikuo Nishimoto's lab while screening for neuroprotective factors against amyloid-beta toxicity. Later independently identified in labs studying BAX protein and IGFBP3 interactions
- Primary mechanism is anti-apoptotic: Humanin binds and neutralizes pro-apoptotic proteins (BAX, tBID) and activates cell-survival signaling through a tripartite receptor complex (gp130 / WSX1 / CNTFR)
- Extends lifespan in C. elegans through autophagy activation (the cellular cleanup process). This is the first peptide shown to extend lifespan via autophagy
- Circulating humanin levels track with healthspan. Children of centenarians carry significantly higher humanin than age-matched controls. Levels drop in Alzheimer's, MELAS, type 2 diabetes, and after preterm birth
- Endogenous humanin rises with vigorous exercise. The peptide overlaps with the cellular benefits of training, which is why MDPs are sometimes called exercise-mimetic signals
- Synthetic analogs HNG (Humanin-G) and HNGF6A are 1,000 to 10,000 times more potent than the native peptide and are used in most published studies. The peptide sold commercially is typically one of these analogs
- Typical community dose is 0.5 to 2 mg subcutaneously, often weekly rather than daily. Cycling is standard. No FDA approval, no completed Phase 2 or 3 human trials as of May 2026
This page is the full 2026 reference on Humanin peptide: discovery, chemistry, mechanism, every documented benefit, the centenarian and biomarker data, community dosing, side effects, contraindications, comparison to other longevity peptides including MOTS-c, and current research status.
What Is Humanin?
A mitochondrial-derived peptide with unusually wide-ranging effects.
Humanin is a 24-amino-acid peptide with the sequence MAPRGFSCLLLLTSEIDLPVKRRA. Its chemical formula is C119H204N34O32S2 and its molecular mass is about 2,687 g/mol. What makes it unusual among peptides is its origin: it is encoded by a gene (MT-RNR2) that sits inside mitochondrial DNA, specifically within the 16S ribosomal RNA gene. This places it in a small class of molecules called mitochondrial-derived peptides (MDPs). Humanin was the first MDP ever identified, in 2001.
Humanin at a Glance
- Chemical name: Humanin (HN)
- Sequence (24-aa cytosolic): MAPRGFSCLLLLTSEIDLPVKRRA
- Sequence (21-aa mitochondrial): Shorter variant, still biologically active
- Gene: MT-RNR2 (mitochondrial DNA, within 16S rRNA gene)
- Molecular formula: C119H204N34O32S2
- Molar mass: ~2,687 g/mol
- Structure: Three-turn alpha-helix
- Native plasma half-life: ~30 minutes (HNG runs longer due to S14G substitution stability)
- Synthetic analogs: HNG (S14G-substitution, 1,000x potency), HNGF6A (10,000x potency)
- Discovery: 2001, Hashimoto / Nishimoto lab (Keio University, Japan)
- Also identified by: Reed lab (BAX interaction), Pinchas Cohen lab (IGFBP3 interaction)
- Species homologs: Rattin in Rattus norvegicus, plus conserved variants across mammals and even some invertebrates
The synthetic analog detail matters. Native Humanin is biologically active but not very potent in pharmacological doses. HNG (Humanin-G, with a single glycine substitution at position 14) is about 1,000 times more potent than native Humanin. HNGF6A is roughly 10,000 times more potent. Most "Humanin" sold as a peptide product is actually one of these analogs, which is why community dosing uses milligram rather than microgram ranges.
How Humanin Works
Three mechanism categories, all pointing at cellular survival.
Anti-apoptotic binding
Humanin's original mechanism (and how it was first discovered) is binding and neutralizing pro-apoptotic proteins that normally trigger cell death:
- BAX binding: BAX is a BCL-2 family protein that, when activated, punches holes in the outer mitochondrial membrane to trigger apoptosis (programmed cell death). Humanin binds BAX and prevents its mitochondrial translocation and activation.
- tBID binding: Similar story for tBID, another pro-apoptotic BCL-2 family member.
- IGFBP3 interaction: Humanin binds insulin-like growth factor binding protein 3, which is involved in both apoptosis signaling and IGF-1 regulation.
The net effect is that cells exposed to stress signals that would normally trigger apoptosis (amyloid-beta toxicity, oxidative stress, ischemia) survive instead. This is the core protective action.
Receptor-based survival signaling
Humanin also works through a tripartite extracellular receptor complex composed of three proteins:
- gp130: The common signaling subunit for the IL-6 cytokine family
- WSX1: A receptor subunit related to IL-27 signaling
- CNTFR: Ciliary neurotrophic factor receptor
When Humanin binds this tripartite complex on a cell surface, it activates downstream pro-survival signaling pathways (PI3K/Akt, MAPK/ERK, STAT3). These are the same pathways that many growth factors and cytokines use to keep cells alive and healthy.
A separate receptor, formyl peptide receptor 2 (FPR2), also binds Humanin and contributes to anti-inflammatory effects.
Autophagy activation (the longevity link)
The most recently characterized mechanism. Humanin activates chaperone-mediated autophagy (a selective form of cellular cleanup where damaged proteins are trafficked to lysosomes for degradation) in a dose-dependent way. Autophagy is one of the central mechanisms through which caloric restriction, rapamycin, and fasting extend lifespan. Humanin is one of the few peptides to tap into this same pathway.
In C. elegans studies, Humanin extends lifespan through an autophagy-dependent mechanism. Blocking autophagy eliminates the lifespan extension effect, which establishes autophagy as the causal pathway.
The IGF-1 / GH axis (why this matters for aging)
This is the mechanism most outdated guides skip. Humanin is part of a regulatory loop with growth hormone and IGF-1, the same axis that governs mammalian lifespan in long-lived knockout mice.
- Long-lived, GH-deficient Ames dwarf mice carry significantly elevated circulating humanin compared to controls.
- Short-lived GH-transgenic mice carry depressed humanin.
- Treating either mice or humans with GH or IGF-1 reduces circulating humanin levels.
This places humanin inside the GH/IGF-1/insulin signaling axis that already governs lifespan in nematodes, flies, and mice. The implication is that humanin is not just another protective peptide. It is one of the messengers the body uses to coordinate slower aging when nutrient and growth signaling drop. That logic is why centenarian families show elevated humanin and why caloric restriction tracks with rising humanin levels.
Humanin as an Aging Biomarker
Humanin is one of the few peptides that doubles as a measurable readout of biological age.
The pattern is consistent across species and cohorts:
- Centenarian offspring: Children of centenarians, who are themselves more likely to reach 100, carry significantly higher circulating humanin than age-matched controls.
- Naked mole-rat: A model of negligible senescence. Humanin levels stay flat across its long lifespan, while levels decline in shorter-lived mammals.
- Disease states: Humanin drops in Alzheimer's disease, MELAS (mitochondrial encephalopathy with lactic acidosis and stroke-like episodes), type 2 diabetes, coronary artery disease, and adults born preterm with reduced left-ventricle ejection fraction.
- Cognitive aging SNP: A 2018 study identified a single-nucleotide polymorphism (rs2854128) in the humanin-coding region. In a cohort of roughly 12,500 older adults, carriers showed lower circulating humanin and accelerated cognitive aging.
None of this proves causation in humans. It does establish humanin as a credible aging biomarker, similar to how klotho, GDF-15, and IGFBP-3 are tracked in longevity research. The practical takeaway for people considering supplementation: low endogenous humanin tracks with worse age-related outcomes, but injecting humanin does not yet have a confirmed lifespan benefit in humans. The biomarker case is stronger than the intervention case.
Humanin and Exercise
Endogenous humanin rises with vigorous physical training.
Several human and animal studies show that intense exercise upregulates circulating humanin alongside MOTS-c. The published language frames MDPs as "cellular cyto- and metabolo-protective signals that parallel those of exercise." In other words, the same peptides your body releases during a hard training block are the peptides under investigation for longevity.
Two practical implications:
- If you are already training hard 4 to 6 times a week, your endogenous humanin is probably higher than a sedentary peer of the same age. Stacking exogenous humanin on top of this baseline is a smaller intervention than it looks.
- Conversely, sedentary aging adults likely carry the lowest endogenous humanin, especially if mitochondrial mass has dropped through sarcopenia. This is the population most likely to feel an intervention effect, and the population where the safety case is also weakest because of comorbidities.
This overlap is why MDPs are often referred to as exercise-mimetic signals in the longevity literature, and why protocols that pair humanin with structured training tend to outperform humanin alone in subjective reports.
Humanin Benefits
Alzheimer's disease protection
The original discovery context. Humanin was identified in a screen for neuroprotective factors against amyloid-beta (Aβ) toxicity in neurons. It protects neurons from Aβ-induced cell death in cell culture and in animal models of Alzheimer's disease, prevents synapse loss in hippocampal neurons, and rescues cerebrovascular smooth muscle cells from Aβ-induced toxicity. Mouse cognition studies show humanin administration improves performance in aged animals. Completed human Alzheimer's trials still do not exist as of 2026, but the mechanistic case is strong and the biomarker data in humans (the rs2854128 SNP cohort, the Alzheimer's drop in circulating humanin) is consistent with the animal mechanism.
Neuroprotection beyond Alzheimer's
Similar protective effects have been documented in animal models of Huntington's disease, stroke (ischemia-reperfusion injury), Parkinson's disease, and general oxidative-stress neuronal injury. The anti-apoptotic mechanism applies broadly to neurons under stress. Rattin, the corresponding peptide in Rattus norvegicus, shows the same Aβ-defense behavior, which suggests the protective effect is conserved across mammals.
Cardiovascular disease
Research in animal models has shown Humanin reduces atherosclerotic plaque formation, protects cardiac muscle against ischemia-reperfusion injury, and may improve outcomes in heart failure models. In one ischemia-reperfusion animal study, intravenous HNG given 15 minutes after ischemic onset (252 μg/kg) reduced infarct size, cardiac arrhythmia, and mitochondrial dysfunction. Human cohort data shows circulating humanin tracks with preserved coronary endothelial function and rises in atherosclerotic plaque tissue as an apparent endogenous protective response. Adults born preterm carry reduced humanin and reduced left-ventricle function, which has prompted interest in humanin as a long-term cardiovascular intervention for that population.
Type 1 and type 2 diabetes
Pancreatic beta cells (the insulin-producing cells destroyed in type 1 diabetes and stressed in type 2 diabetes) respond to Humanin with improved survival and function. Animal models have shown Humanin administration preserves beta cell mass and improves insulin sensitivity. Serum humanin is significantly lower in people with type 2 diabetes and correlates negatively with HbA1c, fasting glucose, and TG/HDL ratio. In one landmark animal study, humanin infusion into the brain improved insulin sensitivity in both liver and skeletal muscle, and a single dose of a potent humanin analog lowered blood glucose substantially in diabetic animals.
Chemotherapy side-effect protection
One of the more practical applications. Humanin and its analogs reduce a list of well-documented chemotherapy side effects in animal studies: chemo-brain (cognitive impairment), peripheral neuropathy, cardiomyopathy, and testicular germ-cell death (a cause of male infertility after treatment with cyclophosphamide, doxorubicin, and similar agents). The protective effect is the same anti-apoptotic mechanism that defends neurons. The catch is that the same mechanism could theoretically protect tumor cells, so co-administration with active chemotherapy is an oncology-supervised question, not a self-experiment. The cleanest use case is post-treatment recovery from chemo-induced neuropathy or cardiomyopathy, not concurrent use during cytotoxic therapy.
Longevity and lifespan extension
The C. elegans lifespan extension finding is the headline longevity result. Humanin levels naturally decline with age in humans and other species, and this decline correlates with age-related disease risk. The naked mole-rat, a long-lived mammal often used as a model of negligible senescence, maintains stable humanin across its lifespan, which strengthens the correlation. Whether exogenous Humanin extends lifespan in mammals (including humans) is unknown and would take decades of trials to establish, but the animal evidence and the centenarian biomarker data support continued research interest.
Oxidative stress protection
Humanin broadly protects cells against oxidative damage, part of the general anti-apoptotic effect. This applies to multiple tissues including brain, heart, kidney, and pancreas.
Anti-inflammatory effects
Reduces pro-inflammatory cytokine production, likely mediated through the FPR2 receptor. Relevant for chronic inflammatory disease states.
Other indications under investigation
Earlier-stage findings, mostly single studies or animal data. None of these are settled, all are tracked in the current literature:
- Age-related macular degeneration (AMD): HNG and other MDPs reduced markers of retinal pigment epithelium damage in animal models of AMD. AMD is one of the most active early MDP applications because the retina is mitochondria-dense.
- Polycystic ovary syndrome (PCOS): HNG improved insulin resistance in PCOS animal models, with the same mechanism implicated in metabolic syndrome.
- Hair growth: HNG promoted dermal papilla cell survival and hair growth in cell and animal studies. No human data.
- Bone and cartilage protection: A patent describes humanin protective effects on cartilage and bone tissues, with secondary findings on prevention of drug-induced bone growth impairment.
- Chronic fatigue syndrome and Q fever fatigue syndrome: Lower circulating humanin observed in both cohorts. Whether supplementation helps is unstudied.
- Cellular senescence: Some studies suggest humanin inhibits cellular senescence. Other studies dispute this. Status: unresolved.
Humanin Dosage
All injection-based. Community protocols reference the potent HNG analog rather than native Humanin.
Standard Humanin Protocol
- Typical dose: 0.5 to 2 mg subcutaneously
- Frequency: Weekly (most common) or daily low-dose (0.5 mg)
- Cycle length: 4 to 8 weeks
- Break: 2 to 4 weeks between cycles
- Cycles per year: 2 to 4
- Timing: Morning injection, subcutaneous into abdomen, thigh, or upper arm. Rotate sites
- Half-life consideration: Native humanin clears in roughly 30 minutes. HNG holds tissue exposure longer because of its S14G substitution, which is part of why weekly dosing is enough at the analog level
No FDA-approved dose exists because there is no FDA approval. Dosing is extrapolated from animal research adjusted for body weight and from community practitioner reports. Most users start at 0.5 mg weekly and adjust based on response. Some protocols (notably Ben Greenfield's published 8-week course) used much lower microgram doses (around 100 μg) which assume native humanin rather than the HNG analog. If you have an unlabeled vial, treat it as the analog and dose conservatively.
Reconstitution
Humanin is sold as a lyophilized powder, typically in 5 mg or 10 mg vials. A 5 mg vial reconstituted with 1 mL bacteriostatic water gives 5 mg/mL. A 1 mg dose is 20 units on a standard U-100 insulin syringe. Use our reconstitution calculator for other vial sizes.
Storage
- Lyophilized vial: Refrigerate at 2 to 8°C. Stable for up to 6 months
- Reconstituted: Refrigerate at 4°C. Use within 4 to 6 weeks
- Protect from light. Do not freeze and re-thaw repeatedly. Aliquot before freezing if longer storage is needed
Humanin Side Effects
Clean profile in animal studies and community reports.
| Side effect | Frequency | Notes |
|---|---|---|
| Injection site reaction | Occasional | Mild redness or soreness. Rotate sites |
| Mild fatigue (first few doses) | Uncommon | Transient, resolves with continued use |
| Mild headache | Uncommon | Usually first week, resolves with hydration |
| Hypoglycemia sensitivity | Rare | Monitor if you are on insulin or sulfonylureas, since Humanin affects insulin sensitivity |
| Lightheadedness when fasted | Rare | More likely when stacked with AMPK activators like MOTS-c on an empty stomach |
No completed Phase 2 or 3 human clinical trials exist as of May 2026, so long-term human safety data is not available. Toxicity studies in animal models have been clean at many multiples of the human-equivalent therapeutic range. Because humanin is naturally produced by your own mitochondria and rises with exercise, it does not suppress endocrine output the way exogenous hormones do.
Who Should Not Use Humanin
Do NOT Use Humanin If You:
- Are pregnant or active breastfeeding (no safety data)
- Are under 18 (no pediatric data)
- Have active cancer (precautionary, because the anti-apoptotic mechanism could theoretically protect tumor cells)
- Have known hypersensitivity to Humanin or any component of the formulation
- Are on concurrent chemotherapy that relies on inducing apoptosis (consult oncologist before use). Post-treatment recovery from chemo-induced neuropathy or cardiomyopathy is a separate question with a more favorable case
- Are on insulin or sulfonylureas, without physician supervision (potential hypoglycemia due to insulin sensitivity changes)
Humanin vs MOTS-c and Other Longevity Peptides
| Peptide | Origin | Primary mechanism | Best for |
|---|---|---|---|
| Humanin | Mitochondrial DNA (MT-RNR2) | Anti-apoptotic, autophagy, IGF-1 axis | Neuroprotection, beta cell survival, longevity biomarker |
| MOTS-c | Mitochondrial DNA (12S rRNA) | AMPK activation, metabolic reprogramming | Exercise mimicry, metabolic health, fat loss |
| SHLP peptides (1-6) | Mitochondrial DNA (16S rRNA) | Varies by peptide; SHLP2 mirrors humanin neuroprotection | Research early-stage |
| Epitalon | Synthetic (Khavinson design) | Telomerase activation, pineal/circadian | Anti-aging, sleep |
| FOXO4-DRI | Synthetic (FOXO4 fragment) | Senolytic (kills senescent cells) | Cellular senescence clearance |
The mitochondrial-derived peptide (MDP) family has expanded since Humanin's 2001 discovery to include MOTS-c, SHLP1 through SHLP6, and a growing list of others. Humanin and MOTS-c are the two best-characterized and the only ones with meaningful community and clinical use. They target overlapping but distinct mechanisms, and stacking them is common in longevity-oriented protocols.
Humanin Stacks
- Humanin + MOTS-c: The mitochondrial-derived peptide longevity stack. Humanin for neuroprotection and beta cell support, MOTS-c for metabolic health and exercise mimicry. Both rise with vigorous training, so the stack reinforces what hard exercise already does.
- Humanin + SS-31 (elamipretide): Mitochondrial protection on two angles. SS-31 stabilizes cardiolipin in the inner mitochondrial membrane while Humanin supports cellular survival signaling.
- Humanin + NAD+ precursors (NMN 250 to 500 mg daily or NR 300 to 600 mg): Cellular energy plus anti-apoptotic support. Common longevity stack.
- Humanin + rapamycin (physician-supervised): Autophagy activation through two different pathways. Clinical, not casual use.
- Humanin + Epitalon: Bioregulator plus MDP for combined anti-aging effects.
- Humanin + structured exercise: Not a peptide stack, but worth flagging. Hard training is the largest known endogenous humanin upregulator. Pairing exogenous humanin with a real training block will outperform either intervention alone in subjective reports.
Avoid combining Humanin with chemotherapy regimens that rely on apoptosis induction, unless coordinated with an oncologist.
Research Status in 2026
Humanin has been the subject of active research for over two decades. The mechanism is well characterized, the anti-apoptotic protection is replicable across cell and animal studies, the lifespan extension in C. elegans is established, and the biomarker case in humans (centenarian offspring, rs2854128 cohort, disease-state declines) is now the strongest piece of human-relevant evidence. What has not happened, as of May 2026, is a completed Phase 2 or Phase 3 human clinical trial for any specific indication.
The main barriers to clinical development mirror what held back DSIP and other broadly-acting peptides: Humanin's mechanism is multi-target, the effect size for any single indication is modest, patent economics for a native mitochondrial peptide are challenging, and the indications with largest patient populations (Alzheimer's, cardiovascular) require very long and expensive trials. Modified analogs like HNG with improved potency and longer half-life could eventually enter dedicated clinical development. Several second-generation HNG derivatives with improved half-life are in early laboratory evaluation, but none have advanced to pivotal human trials at the time of this update.
Where to Buy Humanin
Quality markers matter. Most commercial "Humanin" is actually the HNG analog.
- ≥98% purity verified by independent HPLC and mass spectrometry
- Third-party Certificate of Analysis per batch
- Clear labeling: whether the product is native Humanin, HNG, or HNGF6A (potency differs 1,000 to 10,000 fold between these). An unlabeled vial is a red flag
- Lyophilized vials of 5 or 10 mg
- US-based manufacturing with cold-chain handling
Avoid unlabeled products that do not specify the analog form. For a broader vendor vetting walkthrough, see our best legit peptide vendors guide.