Postoperative Stress Accelerates Atherosclerosis Through Inflammatory Remodeling of the HDL Proteome and Impaired

Dominique M Boucher1,2, Victoria Lorant1,2, Valerie Rochon1,2

  • 1Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.

Insights

Surgical inflammation impairs reverse cholesterol transport (RCT) and promotes foam cell apoptosis, increasing cardiovascular risk. Restoring apolipoprotein A1 (Apoa1) may mitigate these effects.

Area of Science:

  • Cardiovascular Biology
  • Inflammation Research
  • Atherosclerosis

Background:

  • Millions face cardiovascular complications post-surgery, linked to plaque instability.
  • Reverse cholesterol transport (RCT), mediated by HDL and Apoa1, is protective but its response to surgical inflammation is unknown.

Purpose of the Study:

  • To investigate the impact of surgical inflammation on RCT and atherosclerotic plaque stability.
  • To explore the potential of apolipoprotein A1 (Apoa1) restoration in mitigating surgical inflammation's adverse effects.

Main Methods:

  • Utilized an abdominal laparotomy model in ApoE-/- mice on a Western diet.
  • Employed a novel dual-label, dual-cell-type in vivo RCT model to assess macrophage and VSMC RCT.
  • Analyzed patient plasma for cholesterol efflux capacity post-surgery.

Main Results:

  • Surgery acutely impaired RCT and cholesterol efflux, altering HDL composition (increased SAA1/2, reduced Apoa1).
  • Plaques showed increased lipids, PLIN2, and apoptosis, particularly in PLIN2hi foam cells.
  • Macrophage RCT was significantly impaired post-surgery, while VSMC RCT was unaffected; patient plasma showed reduced efflux capacity.

Conclusions:

  • Surgical inflammation rapidly disrupts HDL function and RCT, promoting foam cell apoptosis and plaque destabilization.
  • rh-APOA1 treatment partially restored RCT and reduced plaque lipid accumulation in mice.
  • Targeting Apoa1 may be a strategy to reduce postoperative cardiovascular risk.

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