A five-amino-acid peptide isolated from velvet antler potently inhibited the blood pressure enzyme ACE at very low concentrations and significantly reduced blood pressure when given orally to hypertensive rats.
IC50 = 3.72 μMThe velvet antler pentapeptide inhibited ACE at a concentration of just 3.72 micromolar — indicating very potent enzyme-blocking activity for a food-derived peptide.
What the researchers found
Researchers isolated a specific five-amino-acid peptide (Asp-Asn-Arg-Tyr-Tyr, molecular weight 730.31 Da) from enzymatic digestion of velvet antler that powerfully inhibits angiotensin I-converting enzyme (ACE), a key enzyme in blood pressure regulation. The peptide showed an IC50 value of 3.72 μM against ACE — indicating potent inhibitory activity at very low concentrations. Molecular docking analysis confirmed stable binding between the peptide and ACE at multiple active-site residues. When given orally to spontaneously hypertensive rats, the peptide significantly reduced blood pressure.
Why it matters
ACE inhibitors are among the most widely prescribed blood pressure medications, but current drugs are synthetic pharmaceuticals with side effects like chronic cough. Food-derived peptides that naturally inhibit ACE represent a potential alternative — functional food ingredients that could help manage blood pressure with fewer side effects. Identifying the exact structure and mechanism of these peptides, as this study does, is a critical step toward developing them as practical nutraceuticals.
The numbers in context
Pentapeptide MW 730.31 Da · IC50 = 3.72 μM against ACE · Sequence: Asp-Asn-Arg-Tyr-Tyr
How the study worked
The peptide was purified from alcalase hydrolysate of velvet antler (deer antler in its growth stage). Its structure was determined by quadrupole time-of-flight electrospray ionization mass spectroscopy. ACE inhibition was measured using enzyme reaction assays. In silico molecular docking analysis modeled how the peptide binds to ACE. The antihypertensive effect was tested in vivo by oral administration to spontaneously hypertensive rats (SHRs), a standard animal model for hypertension research.
Who was studied
In vitro enzyme assays and spontaneously hypertensive rats (SHRs); no human subjects
What this study cannot tell us
This study was conducted in vitro and in an animal model — no human data exists for this peptide. The spontaneously hypertensive rat is a useful but imperfect model for human hypertension. The study doesn't address whether the peptide survives gastrointestinal digestion intact in humans, what the optimal dose would be, or whether the blood pressure effects are sustained with chronic use. Velvet antler sourcing also raises sustainability and ethical considerations.
How to read the evidence
This study provides solid in vitro evidence of ACE inhibition with structural characterization, supported by molecular docking and an animal model. However, it remains preclinical — no human studies have been conducted, and oral bioavailability in humans is unknown.
When this study was published
Published in 2023, this is a recent study in the active field of food-derived bioactive peptides. The findings are consistent with similar research on ACE-inhibitory peptides from other protein sources.
The bigger picture
Food-derived ACE-inhibitory peptides are a growing area of nutraceutical research, with candidates sourced from milk, fish, soybeans, and other proteins. Velvet antler adds another source to this list. The broader goal is identifying natural peptides that could help manage blood pressure either as functional foods or dietary supplements, potentially complementing or reducing the need for pharmaceutical ACE inhibitors in mild hypertension. However, the gap between animal studies and proven human efficacy remains substantial.
Questions still open
- Does this pentapeptide survive human gastrointestinal digestion intact, or is it broken down before it can reach the bloodstream and inhibit ACE?
- How does the blood pressure-lowering potency compare to pharmaceutical ACE inhibitors at equivalent doses in human studies?
- Could this peptide be synthesized or produced at scale without relying on velvet antler as a source material?
Common questions
What is ACE and why does inhibiting it lower blood pressure?
Can eating velvet antler lower blood pressure?
Read the original research
Structure Characterization and Antihypertensive Effect of an Antioxidant Peptide Purified from Alcalase Hydrolysate of Velvet Antler.
Food science of animal resources, 43(1), 184-194
Citation
Im, Seung Tae; Lee, Seung-Hong. (2023). Structure Characterization and Antihypertensive Effect of an Antioxidant Peptide Purified from Alcalase Hydrolysate of Velvet Antler.. Food science of animal resources, 43(1), 184-194. https://doi.org/10.5851/kosfa.2022.e70