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Cognitive Enhancement

NSI-189

Formula: C21H27N3O

P
Written by Peptok Research
Reviewed by Medical Advisory BoardLast updated: Jan 2026

Quick Stats

Evidence Strength1/10 (Low)

Based on number and quality of indexed studies

Community Popularity1/10 (Low)

Based on search volume and community interest

Legal Status

⚖️ Investigational drug

Type

Cognitive Enhancement

Route

Oral

Half-life

~17-20 hours

Medical Disclaimer

This content is for informational and research purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before making decisions about peptide use or any medical treatment. Individual results may vary.

Overview

NSI-189 is an experimental nootropic compound being researched for its potential to promote neurogenesis, the growth of new brain cells. It's shown promise in early trials for alleviating depression and enhancing cognitive function, possibly by stimulating hippocampus growth.

Quick Summary

  • 🧬
    What it is:NSI-189 is an experimental nootropic compound being researched for its potential to promote neurogenesis, the growth of new brain cells.
  • 🎯
    Primary use:Cognitive Enhancement applications — see benefits section for details.
  • 📊
    Evidence level:Preliminary — Mostly anecdotal or very early-stage research (1 indexed papers)
  • Bottom line:Very early research phase. Approach with appropriate caution; long-term safety is unknown.

NSI-189 is a synthetic chemical compound under investigation for its potential neurogenic effects. Unlike many nootropics that primarily modulate neurotransmitter activity, NSI-189 is theorized to stimulate the growth of new neurons (neurogenesis) within the hippocampus, a brain region critical for memory and mood regulation. This unique mechanism sets it apart and fuels interest in its potential therapeutic applications. Several early studies have shown promise in treating depression and improving cognitive function, but it's important to note that research is ongoing.

The most compelling aspect of NSI-189 is its potential to physically alter brain structure. Most nootropics work by modulating existing brain function. NSI-189 aims to build new capacity. This is a fundamentally different approach to cognitive enhancement.

How NSI-189 Works

The precise mechanism of action of NSI-189 isn't fully understood, but research suggests it interacts with a protein called brain-derived neurotrophic factor (BDNF). BDNF is crucial for neuronal survival, growth, and differentiation. It supports the health of existing neurons and encourages the formation of new ones. NSI-189 appears to amplify BDNF signaling, leading to increased neurogenesis in the hippocampus.

Specifically, NSI-189 is thought to stimulate the ERK (extracellular signal-regulated kinase) pathway. This pathway is involved in cell growth, proliferation, and differentiation. By activating ERK, NSI-189 promotes the birth and maturation of new neurons. This process is vital for learning, memory, and overall cognitive function.

Additionally, NSI-189 may influence the hippocampal neurogenesis pathway. The hippocampus is a brain region essential for forming new memories and spatial navigation. Studies suggest that NSI-189 can increase the volume of the hippocampus, potentially improving memory and cognitive performance. It's also theorized to have an effect on the TrkB receptor, a receptor for BDNF, further enhancing neurotrophic support.

What the Research Actually Shows

Depression: Multiple studies have investigated NSI-189's potential antidepressant effects. A phase 2, double-blind, placebo-controlled study published in Molecular Psychiatry (Papakostas et al., 2020) found that NSI-189 phosphate showed statistically significant improvements in depressive symptoms compared to placebo in outpatients with major depressive disorder. Another post-hoc analysis of a phase 2 study, published in Annals of Clinical Psychiatry (Johe et al., 2020), indicated that NSI-189 selectively benefited moderately depressed patients. Evidence Grade: Moderate. While these human trials are promising, further research with larger sample sizes is needed to confirm these findings.

Cognitive Enhancement: Research suggests NSI-189 may improve cognitive function, particularly in areas related to memory and learning. A study in the Journal of Diabetes Research (Jolivalt et al., 2022) using a rat model of type 2 diabetes found that NSI-189 reversed memory impairment. These results are supported by observations of increased hippocampal volume in some human trials, but the direct link between NSI-189 and cognitive enhancement in healthy individuals requires more investigation. Evidence Grade: Preliminary. More research is needed to determine the extent of these effects in humans without pre-existing conditions.

Neuroprotection after Stroke: Animal studies suggest NSI-189 may have neuroprotective properties. A study published in the Journal of Cellular Physiology (Tajiri et al., 2017) found that NSI-189 exerted behavioral and neurostructural benefits in stroke rats. These findings suggest that NSI-189 could potentially aid in recovery after brain injury, but these results are currently limited to animal models. Evidence Grade: Animal only. Human trials are needed to determine if these neuroprotective effects translate to humans.

Peripheral Neuropathy: The Journal of Diabetes Research study (Jolivalt et al., 2022) also indicated that NSI-189 could reverse peripheral neuropathy in a rat model of type 2 diabetes. This suggests a potential therapeutic avenue for diabetic neuropathy, a common and debilitating complication of diabetes. Evidence Grade: Animal only. This is an interesting finding, but requires human research to be validated.

NSI-189 vs. P21

Both NSI-189 and P21 are being researched for their cognitive enhancement potential, but they operate through different mechanisms. NSI-189 focuses on neurogenesis, stimulating the growth of new neurons. P21, a derivative of nerve growth factor (NGF), primarily aims to protect existing neurons and enhance their function.

Mechanistically, NSI-189 is thought to increase BDNF signaling and activate the ERK pathway, promoting cell growth and differentiation. P21, on the other hand, binds to the TrkA receptor, mimicking the effects of NGF and supporting neuronal survival and function. P21 is primarily neuroprotective, while NSI-189 is primarily neurogenic.

In terms of research, NSI-189 has undergone some human trials, showing promise in treating depression and improving cognitive function. P21 research is primarily pre-clinical, with studies focusing on its neuroprotective effects in animal models of neurodegenerative diseases. Both are promising, but NSI-189 has a slight edge in terms of human data availability, even though it's still limited.

The Honest Limitations

The research on NSI-189 is still in its early stages. While some human trials have shown encouraging results, the sample sizes have been relatively small, and more extensive research is needed to confirm these findings. Specifically, larger, randomized, controlled trials (RCTs) are necessary to establish the efficacy and safety of NSI-189 for various conditions.

Furthermore, the long-term effects of NSI-189 are not yet fully understood. Most studies have focused on short-term outcomes, and the potential for any long-term side effects remains unknown. More long-term studies are needed to assess the safety and tolerability of NSI-189 over extended periods.

It's also important to note that the precise mechanism of action of NSI-189 is not fully elucidated. While research suggests it interacts with BDNF and the ERK pathway, the exact details of this interaction are still unclear. A deeper understanding of the mechanisms involved could help optimize its therapeutic potential and minimize potential risks.

Specific Tip: Sourcing High-Quality NSI-189

Given that NSI-189 is still an experimental compound, sourcing a reliable and high-quality product is crucial. Many vendors sell research chemicals online, but not all products are created equal. Look for suppliers that provide third-party lab testing results to verify the purity and identity of the compound. These tests should confirm that the product contains the stated amount of NSI-189 and is free from contaminants. This is especially important because NSI-189 is not yet regulated, meaning product quality can vary significantly. Prioritize vendors with transparent quality control processes and positive customer reviews, and always consult with a healthcare professional before using any experimental compound. Use caution and prioritize safety when considering NSI-189.

Benefits & Evidence

Hippocampal neurogenesis

Moderate Evidence

1 studies · 0 human trials

Antidepressant effects

Preliminary

1 studies · 0 human trials

Improved cognitive function

Preliminary

1 studies · 0 human trials

Increased hippocampal volume

Preliminary

1 studies · 0 human trials

Enhanced spatial memory

Preliminary

1 studies · 0 human trials

Pro-neuroplasticity effects

Preliminary

1 studies · 0 human trials

Who Uses NSI-189?

Biohackers & nootropic users

Preliminary

Reported improvements in focus and mood

High-stress professionals

Preliminary

Potential anxiolytic and adaptogenic effects

Students & knowledge workers

Anecdotal

Memory and learning enhancement reported

Not recommended if:

Pregnant or nursing, history of hormone-sensitive cancers, active autoimmune conditions, or pediatric patients. Always consult a physician before starting any peptide protocol.

Dosage Guide

Protocol by Experience Level

ExperienceDoseFrequencyCycleRoute
Beginner20 mgDaily or EOD4–6 wks, 2 wks offOral
Intermediate40 mgDaily4–6 wks, 2 wks offOral
Advanced60 mgDaily (split dose)4–6 wks, 2 wks offOral

Standard Protocol

40 mg per day orally (Phase 2 clinical trial dose)

Notes

Oral bioavailability is good. Phase 2 trials showed mixed results but clear signals for cognitive improvement. Long-term safety data limited. Not a peptide (benzylpiperazine-aminopyridine) but commonly discussed alongside cognitive peptides.

Route

Oral

Half-life

~17-20 hours

Molecular Weight

341.47 g/mol

Disclaimer

This information is for educational purposes only. Dosage information is derived from research literature and community reports. Always consult a qualified healthcare provider before using any peptide.

What the Community Reports

Community data coming soon

We're aggregating Reddit discussions for NSI-189.

Safety Profile

Regulatory Status

Investigational drug. Not FDA-approved. Available as research chemical.

Common

  • Headache
  • Insomnia
  • Mild anxiety initially

Rare

  • Vivid dreams
  • Suicidal ideation (rare, as with all antidepressants)

Serious

No serious adverse events reported in available literature.

Pregnancy: ❌ Not recommended — no safety dataKnown Interactions: 3 documented stacks
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Research

Mechanism of Action

NSI-189 stimulates neurogenesis in the hippocampus through mechanisms that are not fully elucidated. It appears to modulate hippocampal neural stem cell proliferation and survival, increase BDNF and other neurotrophic factors, and enhance synaptic plasticity. MRI studies in trials showed measurable increases in hippocampal volume.

Search Volume Trend

Rank #28
12 months agoPresent
Clinical Trial (Phase 2)2017

NSI-189, a small molecule with neurogenic properties, for treatment of major depressive disorder

Neuropsychopharmacology · Fava M, et al.

Common Stacks

Peptides frequently combined together for synergistic effects.

Semax

Cognitive

Cognitive enhancement stack — anxiolytic + nootropic

Selank

Cognitive

Cognitive enhancement stack — anxiolytic + nootropic

P21

Performance

Commonly combined with P21 for enhanced outcomes

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