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B7-33 – Product Information

  • B7-33 is offered as 6mg lyophilized powder.
  • In the context of research, it is advisable to opt for bacteriostatic water when reconstituting substances rather than sterile water.

B7-33 for sale is a synthesized peptide that could address fibrotic disorders such as cardiac fibrosis. It is currently being researched and investigated as a means of reducing fibrosis in acute and chronic diseases such as acute heart failure, lung inflammation, kidney disease, prostate cancer progression, and others.

Based on available animal studies, B7-33’s ability to produce anti-fibrotic effects by roughly 50% could lead to prolonged survival of affected organs by treating heart failure.

It has been demonstrated, through clinical trials, that B7-33 may reduce excessive scar formation after cardiac injury. It has also shown promise in treating certain vascular disorders and pregnancy preeclampsia.

Despite the mentioned health benefits of B7-33, it is still unclear how this chemical really works due to the lack of significant evidence. For this very reason, B7-33 is inadvisable for human consumption.

PureRawz sells B7-33 for sale for research purposes only.

CAS Number N/A
Molar Mass N/A
Chemical Formula B7-23

What is B7-33?

B7-33 is a single-chain peptide that is a smaller analog of the endogenous relaxin protein.

The relaxin peptide comprises four parts: a signal peptide, a B chain, a C chain, and a COOH terminal. Several studies were initially conducted to replicate these peptide structures, but the results were highly insoluble and inactive.

Following extensive research, scientists modified the structure by adding a B chain and extending the COOH terminal, resulting in the first soluble analog – B7-33 peptide – in 2016.

One of the several synthetic peptides produced from the human, naturally occurring protein H2-relaxin is B7-33. The relaxin protein family, which includes the four proteins relaxin, insulin-like peptide-3, H3-relaxin, and insulin-like peptide-5, is named after the human H2-relaxin protein.

The four endogenous receptors for the relaxin family peptides are split into two pairs. The purpose of each receptor is described below:

RXFP-1: This G protein-coupled receptor affects pregnancy, sperm motility, joint health, and vascular endothelium [R]

RXFP-2: Influences testicular descent [R]

RXFP-3: Mutations for this specific receptor could impact schizotypal personality disorder and certain sleep disturbances [R]

RXFP-4: This last receptor is believed to be expressed in sperm and could influence the function of insulin-like peptide 5. Based on studies, such a quality has been shown to affect hunger/satiation signaling. [R]

Although the benefits of H2 relaxin are robust and significant, there are some known drawbacks to using this protein as a therapeutic agent. The protein could increase heart rate and promote cancer progression when used in full.

Possible Applications of B7-33

B7-33 and Preeclampsia Phenotype

Preeclampsia (PreE) is a pregnancy disorder marked by the onset of new hypertension and a decrease in fetal weight. [R]

B7-33 and its lipidated derivative both reduce MBG- and hyperglycemia-induced CTB dysfunction by attenuating the anti-angiogenic phenotype seen in preE. Furthermore, a relaxin antagonist reduces the effect of B7-33 and its lipidated derivative on CTBs. B7-33 and its lipidated derivative are currently being studied in preclinical trials. [R]

This application of B7-33 still requires more clinical trials and should not be treated as conclusive.

B7-33 and Anti-Fibrotic Properties

B7-33 is the first functionally selective agonist of the RXFP1 complex GPCR. Importantly, with similar potency to H2 relaxin, this small peptide agonist prevented or reversed organ fibrosis and dysfunction in three preclinical rodent models of heart or lung disease. [R]

B7-33’s strong antifibrotic effects were due to its activation of RXFP1-angiotensin II type 2 receptor heterodimers, which induced selective downstream signaling of pERK1/2 and the collagen-degrading enzyme, matrix metalloproteinase (MMP)-2. [R]

In addition, unlike H2 relaxin, B7-33 did not promote prostate tumor growth in vivo. The findings are the first to show that a two-chain cyclic insulin-like peptide can be reduced to a single-chain linear peptide while retaining potent beneficial agonistic effects. [R]

Still, more clinical trials are needed to confirm B7-33’s supposed potent antifibrotic effects.

B7-33 and Myocardial Infarction

Primary cardiomyocytes from adult hearts were isolated in vitro and subjected to simulated ischemia-reperfusion injury (simulated ischemia reoxygenation). B733 (50 and 100 nmol/L) improved cell survival and decreased the expression of GRP78, an endoplasmic reticulum stress marker. [R]

Following that, B733 (100 nmol/L) inhibited tunicamycin (2.5 g/mL)-induced GRP78 upregulation in an extracellular signal-regulated kinase 1/2-dependent manner. [R]

In mice, the novel peptide provides acute cardioprotection and limits myocardial infarction-related adverse remodeling by reducing cardiomyocyte death and endoplasmic reticulum stress while maintaining cardiac function. [R]

These supposed health impacts of B7-33 still lack sufficient evidence. Therefore, more clinical trials are needed.

B7-33 and Blood Vessels

B7-33 could also affect the cardiovascular system, specifically its blood vessels.

Equimolar doses of B7-33 mimicked the acute beneficial vascular effects of serelaxin in rat mesenteric arteries and also prevented endothelial dysfunction in mouse mesenteric arteries induced by placental trophoblast-conditioned media. [R]

As a result, B7-33 should be regarded as a low-cost vasoactive therapeutic in cardiovascular disease. [R]

Some researchers even claim that B7-33 prevented endothelial dysfunction induced by placental trophoblast. [R]

More large-scale laboratory studies are still required for this alleged property of B7-33.

How Does B7-33 Work?

B7-33’s capacity to function preferentially through the pERK pathway over the cAMP-mediated pathway is one of its essential properties.

Aside from the structural difference, the peptide has some other differences from endogenous proteins that are more beneficial than H2-relaxin itself.

Instead of the cAMP pathway, the B7-33 peptide acts via the pERK pathway. H2-relaxin’s antifibrotic properties are traditionally produced via the cAMP pathway, which may potentially stimulate the formation of tumors in the body. This is a significant side effect of the relaxin treatment.

In addition, the peptide has a high affinity for RXFP-1 receptors.

The peptide binds to these RXFP-1 receptors and activates the pERK pathway, resulting in increased synthesis of MMP-2 matrix metalloproteinase chemicals. These chemicals then inhibit scarring of the tissues, preventing fibrosis.

Frequently Asked Questions

Is B7-33 a blood vessel growth stimulator?

B7-33 may promote blood vessel growth and thus could improve blood supply by stimulating VEGF production.

Is B7-33 safe?

The safety of B7-33 to humans is still being investigated. For this reason, we recommend buying this synthetic chemical for the purpose of scientific studies and medical research.

Where can you buy B7-33?

PureRawz is the best place to buy the highest-quality B7-33 online.

We also sell other research chemicals such as SARMS and Nootropics that you can use for your laboratory studies.

In order to be the best supplier of research chemicals, we provide reference materials with every product we sell. All of our products come with an independent, third-party-issued Certificate of Analysis for identification, purity, and concentration.


This information is for educational purposes only and does not constitute medical advice. THE PRODUCTS DESCRIBED HEREIN ARE FOR LABORATORY AND RESEARCH USE ONLY. All clinical research must be conducted with oversight from the appropriate Institutional Review Board (IRB). All preclinical research must be conducted with oversight from the appropriate Institutional Animal Care and Use Committee (IACUC) following the guidelines of the Animal Welfare Act (AWA).
Our content is intended to be used and must be used for informational purposes only. It is very important to do your own analysis and research from Trusted Sources before making any purchase, based on your personal circumstances. You should independently research and verify any information that you find on our Website and wish to rely upon.
By completing and paying for your order, you agree to our Terms and Conditions. Customer satisfaction is our number one priority – if you are not 100% satisfied with the product you received, please contact us at [email protected]
ATTENTION: All our products are for LABORATORY AND RESEARCH PURPOSES ONLY, not for veterinary or human usage.

12 reviews for B7-33

  1. User Avatar: Levi


    Really amazing product. Since I started using this I feel amazing and healthier than ever.

  2. David Cooks

    Excellent product! Shipping was a bit disappointing, but your team sorted it out for me.

  3. Tiffany B

    My test went great! My rabbit went from not moving for a week to an energetic bunny!

  4. George Diaz

    I am very pleased with this product. I feel less bloated and have more energy. I will definitely continue taking it. Thanks so much to B7-33. I highly recommend this product.

  5. Alberto Torres

    I have been looking for this peptide all over the internet and the few spot sites I found had it either looking sketchy or outrageously expensive. I am glad to have finally stumbled here. Thanks Purerawz!

  6. Harry

    It took about three weeks to feel a noticeable difference

  7. Peter Jonas

    My kidney problem is surprisingly better than before. I have been using your B7-33 for a month and a half now. I recommend this

  8. Robert Moore

    It works as expected and is a great value for the price. I will buy again.

  9. Shelby M

    Awesome! I’ve noticed the effectiveness of this product after two weeks. Really impressive.

  10. Erwin G

    Excellent B7-33. Heart health is improving!

  11. Stephen Tremblay

    Great peptide. Very helpful for faster wound healing.

  12. George

    A quality product for cardiac health.

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