P21 (P021) 5mg


Availability: In stockManufactured in USA

Purity: 99%

Buy P21 (P021) Peptide

P21 peptide for Sale. P21 (PO21) is a research peptide that displays strong preventative effects in various cancers and Alzheimer’s Disease. Get P21 for sale April 2024.

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P21 (P021) 5mg
$120.00 Buy Now

Availability: In stockManufactured in USA

Purity: 99%

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$15.00 Flat Rate Shipping Worldwide (Most Countries)

*Includes one 30mL Bacteriostatic Water with orders over $300.00


Last updated on April 5, 2024

Product Description

Buy P21 Peptide – USA Made, High Purity, Premium Quality

P21, also known as Cyclin-dependent kinase inhibitor one or CDK-interacting protein, is a nootropic peptide studied for its effects on improving neurogenesis. Animal studies show that P21 peptide can boost levels of BDNF, inhibiting the formation of Tau proteins and Amyloid plaques seen in Alzheimer’s disease through neurogenesis.

At present, researchers are investigating the effects of P21 on the brain and how it could potentially combat disease.

In this article, we’re going to explore P21 effects, benefits, and research studies. We’ll also show you the best place to buy P21 online for your own research study.

What is P21 Peptide?

P-21 is a modified peptide nootropic originally created from CNTF antibodies. CNTF is a naturally occurring protein responsible for promoting neurotransmitter synthesis and protecting neurons against inflammatory attacks. According to research, this protein also decreases appetite, resulting in reduced food intake and enhanced weight loss as research on animals has shown.

CNTF used to be sold under the brand name Axokine as a treatment for amyotrophic lateral sclerosis. It is no longer sold.

As a small derivative of CNTF, P21 was created through a process known as epitope mapping, which targets antibodies to decipher binding sites.

In fact, antibodies against CNTF receptor active sites were once used to establish the binding site. Then they were used to identify which synthetic peptides replicated this binding and altered it. This led to the formulation of p21. P 21 doesn’t just bind to the receptor, it also passes the blood-brain barrier. Unlike natural CNTF, P21 is small enough to cross this barrier and has stronger plasma stability – more than 95% in fact as research on animals has shown.

How P21 Works

P21 works by enhancing neurogenesis in the dentate gyrus. The dentate gyrus is part of the hippocampal formation and is believed to play a role in the formation of new episodic memories as well as the exploration and learning that happens in new environments and situations. This part of the brain is also responsible for pre-processing information and promoting pattern separation – that which enables mammals to differentiate memories.

Unsurprisingly, neuroscientists are greatly interested in p21 peptide nootropic for its effects on the gyrus.

According to research, P21 can induce a variety of effects in the body, including heightened BDNF levels, enhanced phosphorylated GSK3B levels, and increased AMPA receptor protein levels.

Research in mice [i] indicates that P21 peptide doesn’t bind to the CNTF receptor, implying that it is not an analogue of CNTF. Instead, it seems to inhibit antibodies and molecules that neutralize it. Thereby, the peptide P21 increases the concentration of CNTF and mimics its effects.

Further research suggests that high P21 levels also increases BrdU positive cells (synthetic nucleosides) in the dentate gyrus. In the same study, researchers found that P-21 peptide also promotes cell proliferation in this region, supporting the theory that this proliferation is actually enhanced neurogenesis.

P21 Peptide Benefits

Let’s take a look at some of the health benefits of P21, as discovered by researchers. Indeed, it’s an interesting drug which is magnetic to scientists eager to get this approved by the FDA.


P21 is known for boosting cognition and protecting the central nervous system from internal or external damage. It does this by increasing the development of neurons from precursor cells to complete neurons. What’s more, P21peptide boosts the interconnection between neurons, leading to improved learning and memory as research on animals has shown.

According to the latest p21 research, this molecule offers a number of benefits, especially when it comes to memory, learning, and overall cognitive function. Studies in mice show that this peptide improves reasoning and object discrimination.

In addition, it can heighten levels of GluR1, synapsin 1, and NR1, all hallmarks of neurogenesis. P21 can boost these proteins in disease, but also in health. This means p21 is a vital compound in learning, memory, and brain health as research on animals has shown.

Alzheimer’s Disease

According to studies[ii], P21 treatment increases activity in the dentate gyrus, helping to address the effects of Alzheimers Disease. That’s because AD’s natural reaction to damage in the brain is to heighten activity in the gyrus, but aged brains tend to lack the capability to do that. Thanks to P21 therapy, that can be altered as research on animals has shown.

Scientific findings show that P21’s neurotrophic support results in enhanced levels of brain-derived neurotrophin-4 and neurotrophic factor. Simultaneously, it lessens the mitogenic effects of growth factor 2. Researchers found that administration of P21 injections in mouse models before the onset of AD could serve as a preventative.

Additionally, BDNF has been connected to the diminishing of enzymes that cause tau and amyloid plaque in AD brains. This further suggests that P21 could be a groundbreaking preventative and treatment for Alzheimers.


New research shows that p21 governs all vital cellular functions, all of which play a role in the formation, progression and response of cancerous cells. That’s why scientists are desperately investigating p21 peptide for its function to treat cancer.

In fact, certain chemotherapeutic agents have been developed to stimulate p21 activity with the intention of inhibiting the progression of cancer.

Due to P21’s inhibitory effect on CDK2 activity, this peptide can prevent cancer cell proliferation – in particular, that of breast cancer. Research studies indicate that the expression of estrogen receptor-a gene is initiated by the activation of p21 peptide hormone.

Appetite Suppression

Interestingly, P21 results may also include weight loss. While there are no direct studies linking p21 with fat loss, there is evidence to suggest it may suppress appetite. According to experts, this is a side effect of the stimulation of alpha-melanocyte stimulating hormone synthesis, which occurs by enhanced CNTF levels.

When one increases these levels, P021 boosts levels of alpha-MSH, a compound associated with decreased food intake. So while it’s not a weight loss drug, per se, there is reason to believe it could potentially be one someday.

P21 Side Effects

While scientists consider P21 as a safe compound, there are two potential side effects to watch out for,  as research on animals has shown, including:

  • Tiredness – most neurogenetic compounds product such effects, so this isn’t something to be concerned about.
  • Cognitive rebound – this side effect is rare, but it can happen.

Momentarily, there is inadequate research to legalize P21 as an over-the-counter medicine, which is why it is only available to researchers for the sole purpose of research.

In mice with AD, P21 doesn’t appear to have any side effects. That doesn’t mean the nootropic has no side effects, but it does suggest that it has limited side effects in the case that it reaches clinical trials. So far, the only side effects of P21 peptide noted is lower anxiety levels – which is actually rather a positive effect.

P21 Review 2024

Overall, P21 is a highly researched peptide with a plethora of potential benefits. The P21 drug is a cell cycle inhibitor which plays a significant role in vital cellular processes such as apoptosis, cell cycle arrest, DNA repair, differentiation, and transcriptional regulation. Scientists are keen to learn more about its role in cancer prevention and in treating AD.

Studies suggest that p21 supplementation could result in prevention of Alzheimer’s disease and cancer, improved memory and learning, and even weight loss as research on animals has shown.

More research is required to understand the full benefits of P21 peptide, but if it becomes legalized for consumption, that means the creation of new therapeutic – and potentially life-saving – treatments. And this is a fact that gets scientists extremely excited.

If you read p21 reviews, you’ll find a lot of positive stuff out there regarding its effects and health benefits. The research so far looks highly promising and scientists hope it will make it to clinical trials so that it can be available to the mass. With further research, we’ll no doubt uncover more benefits of p021 peptide and its profound effects on the neurological system.

P21 vs Cerebrolysin

While p21 is often referred to as a derivative of cerebrolysin, they are not the same compound. Whereas p21 peptide is a synthetic analogue of CNTF, cerebrolysin is a peptide mixture with CNTF being only one of its components. P21 is comprised of only four amino acids from CNTF and is shown to be more efficacious than cerebrolysin, as per animal studies.

In recent years, scientists have abandoned cerebrolysin treatment due to it stimulating the production of antibodies against CNTF and gradually becoming completely ineffective. In fact, it can even make things worse.

At one time, this product was one of the best options one could buy. As a complex blend of different brain chemicals, it was initially an effective treatment. However, it produces high levels of foreign CNTF that causes the production of auto-antibodies, leading to adverse effects.

P21 is proven to confiscate these auto-antibodies and help to diminish them, resulting in enhanced efficacy of native CNTF. Studies show it has not shown to lose efficacy over time, either, which is a very good sign.

All in all, when it comes to the cerebrolysin vs P21 debate, the latter is the clear winner.

Where to Buy P21 Peptide?

You can buy P21 for your research here on Research Peptides. While there are many vendors of this peptide, a number of them are selling illegitimate versions of this product, which is resulting in misguided scientific results.

To ensure you get the most accurate results from your experiment, get high purity P21 for sale from this number 1 supplier. In the business for over a decade, they pride themselves in delivering purified peptides which abide by US regulations.

All their products are made in the United States, so you’ll be buying P21 USA. We always advise readers to purchase these proteins from US suppliers, as these tend to follow strict health and safety rules which makes the product more reliable – and safer.

Buy P21 peptide 5mg today; click here to buy.


Author Info and References

Author info: The information provided in this article was taken from studies carried out by recognized researchers, including Li, Bin, Lukas Wanka, Julie Blanchard, Fei Liu, Muhammad Omar Chohan, Khalid Iqbal, and Inge Grundke-Iqbal, Baazaoui, Narjes, and Khalid Iqbal.



[i] Li, Bin, Lukas Wanka, Julie Blanchard, Fei Liu, Muhammad Omar Chohan, Khalid Iqbal, and Inge Grundke-Iqbal. “Neurotrophic Peptides Incorporating Adamicetane Improve Learning and Memory, Promote Neurogenesis and Synaptic Plasticity in Mice.” FEBS Letters 584, no. 15 (June 30, 2010): 3359–3365. doi:10.1016/j.febslet.2010.06.025.


[ii] Baazaoui, Narjes, and Khalid Iqbal. “Prevention of Dendritic and Synaptic Deficits and Cognitive Impairment with a Neurotrophic Compound.” Alzheimer’s Research & Therapy 9, no. 1 (June 27, 2017). doi:10.1186/s13195-017-0273-7.


Cite this article as: Research Peptides Scientist, "P21 (P021) 5mg," in ResearchPeptides.net, April 5, 2024, https://researchpeptides.net/product/peptides/p21-5mg/. Accessed April 11, 2024.


P21 Peptide Research Peptides Scientists

Product Usage: THIS PRODUCT IS INTENDED AS A RESEARCH CHEMICAL ONLY. This designation allows the use of research chemicals strictly for in vitro testing and laboratory experimentation only. All product information available on this website is for educational purposes only. This product has not been approved by the FDA for Human Use. Bodily introduction of any kind into humans or animals is strictly forbidden by law. This product should only be handled by licensed, qualified professionals. This product is not a drug, food, or cosmetic and may not be misbranded, misused or mislabeled as a drug, food or cosmetic.


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