Research background · Updated November 1, 2026
P21 Research: Publications, Study Types and Background
Short answer
P21. As of November 1, 2026, PubMed indexes 56 records matching P21, the earliest from 1991; 12 were published in 2021–2025 and 4 are reviews. ClinicalTrials.gov lists 5 registered studies matching the compound.
- PubMed records
- 56
- Earliest record
- 1991
- Published 2021–2025
- 12
- Reviews
- 4
- Animal-only studies
- 13
- Registered studies
- 5
Publications per year, 2006–2025
26 records in 2016–2025 against 19 in 2006–2015; the busiest year was 2014, with 5.
See the numbers
| Year | PubMed records |
|---|---|
| 2006 | 0 |
| 2007 | 1 |
| 2008 | 0 |
| 2009 | 3 |
| 2010 | 1 |
| 2011 | 0 |
| 2012 | 3 |
| 2013 | 2 |
| 2014 | 5 |
| 2015 | 4 |
| 2016 | 3 |
| 2017 | 3 |
| 2018 | 1 |
| 2019 | 4 |
| 2020 | 3 |
| 2021 | 3 |
| 2022 | 3 |
| 2023 | 3 |
| 2024 | 3 |
| 2025 | 0 |
Study types
| All PubMed records | 56 |
|---|---|
| Reviews | 47% |
| Animal studies (no human subjects indexed) | 1323% |
| Indexed as clinical trials | 00% |
| Registered on ClinicalTrials.gov | 5 |
Categories overlap and follow PubMed’s own indexing; recent records may not be indexed yet.
Primary research directions
What 1 of the most-cited and most recent P21 papers report, in their own authors’ terms. Each line links the paper it came from.
Cognition in an Alzheimer's model
In an Alzheimer's disease mouse model fed P021 from early life, the treatment rescued cognitive deficits at four months and reduced abnormal tau hyperphosphorylation.
MiceWei W 2020Alzheimer's research & therapyPMID 32854771
Most-studied topics
The Medical Subject Headings (MeSH) PubMed indexers most often marked as a main topic, across 56 of the 56 records. They describe what the literature is about, not what P21 does.
- Alzheimer Disease11 papers
- Cyclin-Dependent Kinase Inhibitor p218 papers
- Proliferating Cell Nuclear Antigen8 papers
- Ciliary Neurotrophic Factor5 papers
- Muscular Atrophy, Spinal4 papers
- Adamantane3 papers
- Cognitive Dysfunction3 papers
- DNA Repair3 papers
Key papers
Earliest indexed record
Chung DL (1991). Biochemical and biophysical research communications.
PMID 1764089Most-cited paper · 492 citations
Umar A (1996). Cell.
PMID 8858149Most-cited #2 · 460 citations
Bateman RM (2016). Critical care (London, England).
PMID 27885969Most-cited #3 · 93 citations
Kazim SF (2016). Molecular neurodegeneration.
PMID 27400746
Citation counts from NIH iCite, among the 56 records sampled. Titles are left out; open each record on PubMed to read it.
Identity
| Identity data | On request |
|---|
Identity data from PubChem, retrieved November 1, 2026, on the P21 page.
How these numbers were counted
- PubMed search, run November 1, 2026:
"P21 peptide"[tiab] OR "P021"[tiab] OR "P021 peptide"[tiab]re-run it. Study types add PubMed’s own filters (review, clinical trial, animals not humans). - Topics: MeSH major-topic headings counted across up to 400 of the matching records; headings for study set-up (species, sex, age) are left out.
- Citations: NIH iCite citation counts for the same records.
- ClinicalTrials.gov search:
P021re-run it. Any phase, any status.
This page reports what has been published and what papers say they found, with each source linked. It gives no dosing or usage information, and nothing here is a reason to use P21 outside a laboratory.
Wholesale supply
P21, sourced to order for research.
Not held in the listed catalog. Tell us the vial size and the number of vials and we come back with availability, documentation and pricing in writing.
P21 research questions
How much research has been published on P21?
PubMed indexes 56 records matching P21 (searched November 1, 2026), including 4 reviews and 0 records indexed as clinical trials. 12 were published in the five years 2021–2025.
When was P21 first described in the literature?
The earliest PubMed record matching P21 is from 1991 (Chung DL, Biochemical and biophysical research communications, PMID 1764089).
What topics does the P21 literature cover?
The subject headings PubMed indexers most often marked as a main topic of P21 papers are Alzheimer Disease, Cyclin-Dependent Kinase Inhibitor p21, Proliferating Cell Nuclear Antigen, Ciliary Neurotrophic Factor. These describe what the literature is about. Findings from individual papers, with their sources, are summarized on this page.
Is P21 sold for human use?
No. Vanta Foundry supplies it for laboratory research use only. Not for human or veterinary use, and not a drug, food, cosmetic or dietary supplement.
Where can I buy P21 wholesale for research?
We source P21 to order rather than stock it. Tell us the vial size and number of vials on WhatsApp or by email and the quote confirms availability, documentation and pricing.
Research materials supplied by Vanta Foundry are for laboratory research use only. They are not for human or veterinary use and are not drugs, foods, cosmetics or dietary supplements. Websites and payment processing are business services for research-supply brands.
All compounds: research peptide publication statistics.