Resveratrol Downregulates Biomarkers of Sepsis Via Inhibition of Proteasome's Proteases

Shock. 2018 Nov;50(5):579-588. doi: 10.1097/SHK.0000000000001080.

Abstract

Lipopolysaccharide (LPS) is the main agonist of gram-negative bacteria and initiates inflammation. We recently reported that plasmas from sepsis patients revealed increased levels of following group of biomarkers; VCAM-1, ICAM1, CRP, resistin, and proteasome LMP subunits. Our objective here was to compare effects of resveratrol (shown to be a nonspecific proteasome inhibitor by us) and a known LMP7 inhibitor (ONX-0914, specific inhibitor) on proteasome's activities, as well as on inflammatory markers mentioned above in human blood monocytes. Using fluorescence-based assays on blood monocytes purified proteasomes, resveratrol (0-100 μM) inhibited all three protease activities, predominantly LMP7. Similarly, resveratrol inhibited all three protease activities using cell-based luminescence assay. In contrast, ONX-0914 was more selective and potent for LMP7 activity. Resveratrol and ONX-0914, both significantly inhibited expression of LPS-induced biomarkers mentioned above in CD14 monocytes. Moreover, resveratrol itself, as well as in combination with LPS, accumulated pIκBα in CD14 monocytes. Collectively, our data suggest that resveratrol is a less potent inhibitor of all three; CT-like (predominantly LMP7), T-like and PA protease activities and is less toxic to human monocytes than ONX-0914 (a selector inhibitor of only LMP7) as observed by an autophagy detection kit. Also, resveratrol reduces LPS-induced inflammatory cytokine expression by decreasing the translocation of NF-κB due to an increase in inhibitor pIκBα. Therefore, resveratrol can be used to curb inflammation in diseased states like sepsis and other disorders.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Autophagy / drug effects
  • Biomarkers / blood*
  • Cell Survival / drug effects
  • Cells, Cultured
  • Humans
  • Lipopolysaccharides / pharmacology
  • Monocytes / drug effects
  • Monocytes / metabolism
  • Oligopeptides / pharmacology
  • Proteasome Endopeptidase Complex / metabolism
  • Real-Time Polymerase Chain Reaction
  • Resveratrol / pharmacology*
  • Resveratrol / therapeutic use
  • Sepsis / blood*
  • Sepsis / enzymology*
  • THP-1 Cells

Substances

  • Biomarkers
  • Lipopolysaccharides
  • Oligopeptides
  • PR-957
  • Proteasome Endopeptidase Complex
  • Resveratrol