Humanin: Scientific Profile

Publicado el 12 de julio de 2026 · Actualizado el 28 de agosto de 2026

Humanin (HN, CAS 330936-69-1) is a 24-amino-acid mitochondria-derived peptide (MDP), encoded within the mitochondrial 16S rRNA region (MT-RNR2). In research models it is studied for its cytoprotective and antiapoptotic action, mainly through the inhibition of the proapoptotic protein Bax and signaling via surface receptors. Reagent for research use only.

Humanin (HN) is a 24-amino-acid peptide (sequence MAPRGFSCLLLLTSEIDLPVKRRA; CAS 330936-69-1; molecular formula C119H204N34O32S2; approximate molecular weight 2687.18 g/mol) that belongs to the emerging class of mitochondria-derived peptides (MDP). Its distinctive feature is its unusual genetic origin: the coding sequence of Humanin is located within the mitochondrial gene MT-RNR2, which encodes the 16S ribosomal RNA. This places it alongside other MDPs such as the SHLP peptides and MOTS-c within a model of mitochondria-nucleus and mitochondria-cell communication that has reoriented the way biogerontological research conceives the role of the mitochondrial genome. There is both a mitochondrial reading frame and putative nuclear copies, and the literature describes synthetic variants of increased potency, in particular the analog [Gly14]-Humanin (known as HNG or S14G-Humanin), widely used in preclinical studies for its greater stability and activity.

Humanin was identified in the early 2000s in the context of Alzheimer's disease research, when its expression was detected in a relatively preserved brain region of patients and it was observed to confer protection against beta-amyloid peptide-associated toxicity in cell systems. Since then, the body of work has expanded toward models of oxidative stress, glucose metabolism, cell survival, and aging. In humans, various observational studies have described that circulating concentrations of Humanin tend to decline with age, which has fueled interest in this peptide as a marker and as an experimental tool within longevity and aging-biology research. It should be emphasized that these associations are correlational and that Humanin is not an approved drug; its use belongs entirely to the realm of laboratory research.

From a structural standpoint, Humanin is a short peptide that in solution adopts partially helical conformations and contains residues key to its function, among them position 14 (serine in the native form; its substitution by glycine generates the potent HNG analogue) and cysteine residues involved in dimer formation. Its relatively small size and amphipathic character are relevant to its ability to interact with both intracellular proteins and membrane receptors.

The mechanism of action of Humanin described in the preclinical literature is multifaceted and operates through at least two main pathways. The first is intracellular and antiapoptotic: Humanin binds to and inhibits the proapoptotic protein Bax of the Bcl-2 family, preventing its translocation to the outer mitochondrial membrane and thereby blocking the cascade of mitochondrial permeabilization and cytochrome c release that leads to cell death. Its interaction with other proapoptotic proteins such as Bid and BimEL, and with the insulin-like growth factor binding protein IGFBP-3, has also been described, which connects Humanin to the IGF-1 signaling axis. The second pathway is extracellular and is mediated by surface receptors: Humanin can signal through a tripartite receptor complex formed by CNTFR (ciliary neurotrophic factor receptor), WSX-1 and gp130, activating survival cascades such as STAT3, and it has also been linked to the formyl peptide receptor FPR2/FPRL1. Through these routes, research models have documented cytoprotective, antiapoptotic, antioxidant effects and modulation of insulin signaling and cellular energy metabolism.

The documented research applications for Humanin are concentrated on several fronts. In neurobiology, it has been explored in in vitro and in vivo models of beta-amyloid toxicity and neuronal stress, as a tool for studying neuroprotection mechanisms. In metabolic biology, its relationship with insulin sensitivity, glucose homeostasis, and the protection of pancreatic beta cells has been investigated in experimental models. In cardiovascular biology, various preclinical studies have examined its role in models of ischemia-reperfusion and endothelial protection. And within aging research, Humanin and its analogs are studied as part of the paradigm of mitochondrial signaling and its possible relationship with longevity, drawing on observations of its decline with age and its expression in restriction models and in long-lived organisms.

As for the level of evidence, it is fair to classify Humanin as a compound with a substantial base of preclinical data — abundant in vitro and animal-model studies, together with observational data in humans on circulating concentrations — but without clinical trials supporting an approved therapeutic use. There is no pharmaceutical product based on Humanin, and much of the most compelling mechanistic work comes from synthetic analogs such as HNG rather than from the native peptide. For this reason, any interpretation of its effects must remain within the framework of basic and translational research, avoiding premature clinical extrapolations. As a research reagent, Humanin offers laboratories a well-defined tool for interrogating the pathways of Bax-dependent apoptosis, gp130/STAT3 signaling, and the growing field of mitochondria-derived peptides.