Quick summary
Neurotrophin-3 (NT-3) is a neurotrophic growth factor that supports neuron survival and differentiation via TrkC receptors. It is studied for peripheral neuropathy, spinal cord injury, and hearing loss, though clinical use is limited by its short half-life and poor CNS penetration.
Overview
Neurotrophin-3 (NT-3) is a neurotrophic growth factor and member of the neurotrophin family, which includes NGF, BDNF, and NT-4. NT-3 supports the survival, development, and differentiation of neurons, particularly proprioceptive sensory neurons and oligodendrocytes. It is studied for potential applications in peripheral neuropathy, spinal cord injury, hearing loss, and neurodegenerative disease.
Mechanism of action
NT-3 binds with highest affinity to the TrkC (NTRK3) receptor tyrosine kinase, triggering autophosphorylation and activation of downstream signaling cascades including PI3K/Akt (promoting neuronal survival), MAPK/ERK (stimulating differentiation and synaptic plasticity), and PLCγ (modulating calcium signaling). NT-3 also binds the pan-neurotrophin receptor p75NTR, which can modulate either survival or apoptosis depending on cellular context. NT-3 promotes myelination by supporting oligodendrocyte precursor maturation.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| neuropathy research / preclinical dosing | subcutaneous | 0.5–4 mg/kg | daily or every other day per protocol | |
| central delivery research | intravenous | 0.1–1 mg/kg | per experimental design |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Preclinical studies demonstrate NT-3's role in rescuing sensory neurons after injury and promoting axonal regeneration. Phase I/II trials in HIV-associated sensory neuropathy showed some benefit. Animal studies support NT-3 in cochlear hair cell survival and hearing preservation after noise damage. Challenges include blood-brain barrier penetration and short plasma half-life, driving research into gene therapy and viral vector delivery of NT-3.[1][2][3][4]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Neurotrophin-3 for synergistic effects.
Legal status
NT-3 is not approved for human clinical use and is classified as a research reagent. Clinical trials have used recombinant NT-3 under IND applications.
Sourcing & access
Research compound
Neurotrophin-3 is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).
Frequently asked questions
Neurotrophin-3 (NT-3) is a member of the neurotrophin family of growth factors that supports the survival, development, and differentiation of neurons, particularly proprioceptive sensory neurons and oligodendrocytes involved in myelination.
NT-3 binds to the TrkC (NTRK3) receptor tyrosine kinase, activating PI3K/Akt survival signaling, MAPK/ERK differentiation pathways, and PLCgamma calcium signaling. It also binds the p75NTR pan-neurotrophin receptor, which can modulate survival or apoptosis depending on context.
In research settings, reported side effects include injection site reactions, hyperalgesia (sensory overstimulation), myalgia, and allodynia at high doses. NT-3 is classified as research-only and is not approved for human clinical use.
NT-3 research focuses on peripheral neuropathy (including HIV-associated sensory neuropathy), spinal cord injury repair, cochlear hair cell survival for hearing preservation, and neurodegenerative disease. Gene therapy delivery methods are being explored to overcome its short plasma half-life.
Research references
- NT-3 neurotrophin: neuronal survival, differentiation, and axonal growthPubMed
- Neurotrophin-3 in sensory and motor neuron development and maintenancePubMed
- NT-3 delivery for peripheral nerve injury repair: preclinical studiesPubMed
- Neurotrophin-3 and TrkC signaling in proprioceptive neuron specificationPubMed