Copper-Binding Peptides Attenuate Microglia Inflammation through Suppression of NF-kB Pathway

Mol Nutr Food Res. 2021 Nov;65(22):e2100153. doi: 10.1002/mnfr.202100153. Epub 2021 Sep 28.

Abstract

Scope: Activation of microglia, the resident immune cells of the central nervous system, has been related to the etiology and progression of neurodegenerative diseases; thus, finding novel approaches to suppress the neuroinflammatory process is of utmost relevance.

Methods and results: The anti-inflammatory activity of whey Cu-, Fe-, and Zn-binding peptides and their possible underlying mechanism of action were evaluated in microglia. Whey metal-binding peptides decreased nitric oxide production and tumor necrosis factor α (TNF-α) at mRNA and protein levels by stimulated BV-2 microglia in comparison to the control with no peptide treatment. The hydrophobicity, specific sequences, and possible synergistic effects seem to play a role. Cu-binding peptides (Cu-bp) presented anti-inflammatory activity both in BV-2 and primary microglia cultures. These peptides exert their action by suppressing nuclear factor kappa B (NF-kB) pathway since nuclear translocation of NF-kB p65 is decreased by roughly 30% upon Cu-bp treatment. Specific sequences identified in Cu-bp showed high affinity to bind NF-kB p65 by molecular docking (up to -8.8 kcal mol-1 ), corroborating the immunofluorescence studies.

Conclusion: Cu-bp represent food-derived peptides that may be useful for neuroprotective purposes. Chelation of copper excess in the CNS and the bioavailability of such peptides, as well as their behavior in in vivo models, deserve further research for future applications.

Keywords: food-derived peptides; metal chelation; molecular docking; neuroinflammation; primary microglia.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Copper / metabolism
  • Copper / pharmacology
  • Humans
  • Inflammation / metabolism
  • Lipopolysaccharides / pharmacology
  • Microglia* / metabolism
  • Molecular Docking Simulation
  • NF-kappa B* / metabolism
  • Nitric Oxide / metabolism
  • Peptides / metabolism
  • Peptides / pharmacology
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Lipopolysaccharides
  • NF-kappa B
  • Peptides
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide
  • Copper