Colivelin

What it is

Colivelin is a synthetic hybrid neuroprotective peptide created by attaching the 9-amino-acid peptide ADNF9 (activity-dependent neurotrophic factor core sequence) to the N-terminus of AGA-(C8R)HNG17, a potent humanin derivative. Humanin is a 24-amino-acid peptide encoded in the mitochondrial genome that activates a JAK2/STAT3 prosurvival signaling pathway; the derivative AGA-(C8R)HNG17 is approximately 10^5-fold more potent than native humanin. The ADNF9 component adds a complementary second neuroprotective pathway through calcium/calmodulin-dependent protein kinase IV (CaMKIV) signaling. The result is that colivelin activates two independent prosurvival pathways simultaneously: (1) the ADNF9-mediated CaMKIV pathway and (2) the humanin-mediated STAT3/JAK2 pathway. This dual-pathway engagement provides neuroprotection at femtomolar concentrations — approximately 10^3 to 10^7-fold more potent than the parent humanin peptide. In vitro, colivelin provides complete neuroprotection against familial Alzheimer's disease gene toxicity and amyloid-beta at concentrations as low as 100 femtomolar. The JAK2/STAT3 pathway activation is mechanistically important for Alzheimer's pathology: amyloid-beta (Aβ1-42) suppresses phospho-STAT3 levels in hippocampal neurons in an age-dependent manner; phospho-STAT3 levels decrease in both Alzheimer's model mice and human Alzheimer's patients' hippocampi; JAK2/STAT3 inactivation reduces choline acetyltransferase (ChAT) expression and desensitizes muscarinic M1 receptors, providing a mechanistic link between Aβ toxicity and cholinergic dysfunction. Colivelin restores JAK2/STAT3 signaling and completely reverses Aβ-induced cognitive deficits in Tg2576 mice. Additional mechanisms include prevention of calcium overload in hippocampal neurons, restoration of hippocampal long-term potentiation (LTP) suppressed by amyloid-beta, and inhibition of axonal damage markers with promotion of axonal growth following ischemia via JAK/STAT3. In ALS model mice (G93A-SOD1), intracerebroventricular colivelin extended survival and improved motor performance vs. controls. Biodistribution studies showed 0.58% of radiolabeled colivelin reached the mouse brain 2 minutes after IV injection, indicating modest but measurable central nervous system penetration. Colivelin forms a stable monomeric structure in PBS — unlike humanin's strong self-association tendency — attributed to structural domination by the ADNF9 component.

Class: Synthetic hybrid neuroprotective peptide / STAT3 activator / CNTF pathway agonist — fusion of ADNF9 and humanin analog AGA-(C8R)HNG17

What it's studied for

• Alzheimer's disease — cognitive impairment and amyloid pathology Animal studies only
  • APP/PS1 transgenic mice (9 months old) treated with intranasal colivelin: prevented impairments in object recognition, working memory, and spatial memory. Reversed hippocampal LTP suppression on electrophysiology. Chronic colivelin reduced amyloid-beta deposition in the hippocampus on immunochemistry. Provides in vivo PMID 28731445 Wu M et al. J Alzheimers Dis. 2017.
  • Founding study: ICV administration in mice completely suppressed Aβ-induced memory impairment and prevented hippocampal neuronal loss. IP administration also effective, suggesting BBB penetration. In vitro: complete neuroprotection at 100 femtomolar — 10^3–10^7-fold more potent than humanin. Two independent mechanisms: PMID 16267233 Chiba T et al. J Neurosci. 2005.
  • Tg2576 AD model mice: colivelin completely restored cognitive function by activating JAK2/STAT3. Phospho-STAT3 age-dependently decreased in both AD mice and human AD patients' hippocampi. ICV Aβ1-42 downregulated phospho-STAT3; anti-Aβ immunization restored it. Establishes JAK2/STAT3 disruption as mechanistic link betw PMID 18813209 Chiba T et al. Mol Psychiatry. 2009.
  • Rat intrahippocampal colivelin injection (0.2 nmol): prevented Aβ25-35-induced Morris water maze deficits, nearly completely prevented LTP suppression, and inhibited Aβ-induced calcium overload in primary hippocampal neurons. Demonstrates multiple neuroprotective mechanisms against Aβ toxicity. PMID 25332198 Wu MN et al. Hippocampus. 2015.
• ALS (Amyotrophic Lateral Sclerosis) — motor neuron neuroprotection Animal studies only
  • G93A-SOD1 ALS model transgenic mice: ICV colivelin produced dose-dependent improvements in motor performance and significantly extended survival vs. controls or ADNF alone. Histology at 120 days showed increased motoneuronal survival in spinal cords of treated animals. Establishes colivelin efficacy across a second maj PMID 16564029 Chiba T et al. Biochem Biophys Res Commun. 2006.
• Cerebral ischemia / stroke neuroprotection Animal studies only
  • Transient focal cerebral ischemia mouse model (60-min MCAO): colivelin treatment decreased neurological deficits and reduced infarct lesion size. Inhibited axonal damage markers and neuronal death. Upregulated anti-apoptotic genes; promoted axonal growth up to 2 weeks post-stroke. Mechanism: JAK/STAT3 pathway activatio PMID 31374230 Zhao H et al. Neuroscience. 2019.
• Neuroprotection — general neurodegeneration and memory Animal studies only
  • Review: colivelin activates two independent prosurvival pathways (CaMKIV and STAT3). Neuroprotection at femtomolar concentrations confirmed against multiple AD-relevant neurotoxic triggers. Peripheral and ICV routes effective. Both AD and ALS models show efficacy. Hybrid peptide design combining ADNF9 and potent humani PMID 17519506 Chiba T et al. Mol Neurobiol. 2007.
  • Rat multiple T-maze spatial memory test: colivelin and its des-leucine analogue showed highest activity among humanin derivatives in reversing QNB-induced (anticholinergic) spatial memory impairment. Confirms colivelin's superior potency among humanin family peptides for cognitive protection in rodents. PMID 18647630 Kunesová G et al. Peptides. 2008.

Community-reported dosing

Tier key: Research = PMID-cited study · [C] = scraped community source · [S] = model-synthesized from aggregate community reports (softer evidence). How we source.

Safety signals

• No human safety data exists. No Phase I clinical trial has been published in any reviewed abstract. All safety inference is from rodent models. PMID 16267233
• No adverse events described in any reviewed animal study abstract, including the ALS survival study with repeated ICV dosing through 120 days. Absence of reported events in preclinical studies does not establish human safety. PMID 16564029
• Colivelin labeled derivatives (FITC, biotin, 99mTc) confirmed specific cell binding and low-level brain penetration (0.58% at 2 min post-IV) in healthy mice with no adverse events reported in biodistribution protocol. PMID 25575783

Contraindications

• No formal contraindications established in reviewed literature. Compound has not been evaluated in human clinical trials. Individuals on immunosuppressants or medications affecting JAK/STAT3 signaling pathways should be aware of potential interactions. PMID 19663649