Salmon Skin Peptide LDKVFR Blocks Diabetes Drug Target DPP-IV
A hexapeptide (LDKVFR) isolated from salmon skin collagen inhibited DPP-IV with IC50 of 128 µM through hydrogen bonds and hydrophobic interactions with the enzyme.
Quick Facts
What This Study Found
Salmon skin collagen was broken down by four different enzymes. The trypsin-digested version showed the strongest DPP-IV inhibition at 66% at 10 mg/mL.
After separating the fragments by size, the smallest fraction (under a certain molecular weight) had an IC50 of 0.79 mg/mL. Further purification identified a novel peptide, LDKVFR, with an IC50 of 0.1 mg/mL (128.71 micromolar).
Molecular docking showed LDKVFR binds to DPP-IV through six hydrogen bonds and eight hydrophobic interactions, explaining its inhibitory activity.
Key Numbers
66.12% DPP-IV inhibition at 10 mg/mL (trypsin hydrolysate); LDKVFR IC50 = 0.1 mg/mL (128.71 μM); 6 hydrogen bonds, 8 hydrophobic interactions
How They Did This
This was a laboratory study. Researchers hydrolyzed salmon skin collagen with pepsin, trypsin, papain, or Alcalase. Fractions were separated by ultrafiltration and chromatography. DPP-IV inhibition was measured using an enzymatic assay. Binding was modeled using molecular docking software.
Why This Research Matters
DPP-IV inhibitors are an established class of diabetes medications. Finding natural peptides from food sources like salmon skin that can block this enzyme opens the door to food-derived alternatives or supplements.
Salmon skin is a fish processing byproduct, so using it to produce bioactive peptides could add value to waste material while creating potential health products.
The Bigger Picture
DPP-IV inhibitors (gliptins) are a major class of diabetes drugs. Finding natural peptide inhibitors from food waste like salmon skin could lead to functional foods or nutraceuticals for blood sugar management, while adding value to fish processing byproducts.
What This Study Doesn't Tell Us
This was entirely a lab-based study. No cell, animal, or human testing was done to see if LDKVFR survives digestion or reaches the bloodstream in active form.
The IC50 of 128 micromolar is relatively high compared to pharmaceutical DPP-IV inhibitors, which work at nanomolar concentrations.
Questions This Raises
- ?Does LDKVFR survive human digestion to reach the bloodstream?
- ?How does its potency compare to drug DPP-IV inhibitors like sitagliptin?
- ?Could salmon skin hydrolysates be marketed as a functional food for blood sugar?
Trust & Context
- Key Stat:
- 128 µM IC50 salmon skin hexapeptide LDKVFR inhibits DPP-IV, the same enzyme targeted by diabetes drugs like sitagliptin
- Evidence Grade:
- Preliminary evidence from in vitro enzyme inhibition and molecular docking. No cell, animal, or human testing.
- Study Age:
- Published in 2020. Food-derived bioactive peptides for metabolic health continue to be explored.
- Original Title:
- Identification of novel DPP-IV inhibitory peptides from Atlantic salmon (Salmo salar) skin.
- Published In:
- Food research international (Ottawa, Ont.), 133, 109161 (2020)
- Authors:
- Jin, Ritian(2), Teng, Xiangyu, Shang, Jiaqi, Wang, Dangfeng, Liu, Ning
- Database ID:
- RPEP-04887
Evidence Hierarchy
Frequently Asked Questions
What is DPP-IV and why inhibit it?
DPP-IV is an enzyme that breaks down GLP-1, a hormone that helps control blood sugar. By inhibiting DPP-IV, GLP-1 levels stay higher, improving blood sugar control. This is how diabetes drugs like sitagliptin (Januvia) work.
Could eating salmon help control blood sugar?
This peptide comes from salmon skin collagen, not salmon meat. Whether eating salmon or collagen supplements would deliver enough LDKVFR to affect blood sugar is not yet known.
Read More on RethinkPeptides
Cite This Study
https://rethinkpeptides.com/research/RPEP-04887APA
Jin, Ritian; Teng, Xiangyu; Shang, Jiaqi; Wang, Dangfeng; Liu, Ning. (2020). Identification of novel DPP-IV inhibitory peptides from Atlantic salmon (Salmo salar) skin.. Food research international (Ottawa, Ont.), 133, 109161. https://doi.org/10.1016/j.foodres.2020.109161
MLA
Jin, Ritian, et al. "Identification of novel DPP-IV inhibitory peptides from Atlantic salmon (Salmo salar) skin.." Food research international (Ottawa, 2020. https://doi.org/10.1016/j.foodres.2020.109161
RethinkPeptides
RethinkPeptides Research Database. "Identification of novel DPP-IV inhibitory peptides from Atla..." RPEP-04887. Retrieved from https://rethinkpeptides.com/research/jin-2020-identification-of-novel-dppiv
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.