Low grade intravascular hemolysis associates with peripheral nerve injury in type 2 diabetes

PLoS One. 2022 Oct 17;17(10):e0275337. doi: 10.1371/journal.pone.0275337. eCollection 2022.

Abstract

Type 2 diabetes (T2D) induces hyperglycemia, alters hemoglobin (Hb), red blood cell (RBC) deformability and impairs hemorheology. The question remains whether RBC breakdown and intravascular hemolysis (IVH) occur in T2D patients. We characterized RBC-degradation products and vesiculation in a case-control study of 109 T2D patients and 65 control subjects. We quantified heme-related absorbance by spectrophotometry and circulating extracellular vesicles (EV) by flow cytometry and electron microscopy. Heme-related absorbance was increased in T2D vs. control plasma (+57%) and further elevated in obese T2D plasma (+27%). However, large CD235a+ EV were not increased in T2D plasma. EV from T2D plasma, or shed by isolated T2D RBC, were notably smaller in diameter (-27%) and carried heme-related absorbance. In T2D plasma, higher heme-related absorbance (+30%) was associated to peripheral sensory neuropathy, and no other vascular complication. In vitro, T2D RBC-derived EV triggered endothelial stress and thrombin activation in a phosphatidylserine- and heme-dependent fashion. We concluded that T2D was associated with low-grade IVH. Plasma absorbance may constitute a novel biomarker of peripheral neuropathy in T2D, while flow cytometry focusing on large EV may be maladapted to characterize RBC EV in T2D. Moreover, therapeutics limiting IVH or neutralizing RBC breakdown products might bolster vasculoprotection in T2D.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / metabolism
  • Case-Control Studies
  • Diabetes Mellitus, Type 2* / complications
  • Diabetes Mellitus, Type 2* / metabolism
  • Erythrocytes / metabolism
  • Heme / metabolism
  • Hemoglobins / metabolism
  • Hemolysis
  • Humans
  • Peripheral Nerve Injuries* / metabolism
  • Phosphatidylserines / metabolism
  • Thrombin / metabolism

Substances

  • Biomarkers
  • Hemoglobins
  • Phosphatidylserines
  • Heme
  • Thrombin

Grants and funding

Project ‘RépaDia’ of the Fondation de France to OBB, Project ‘BiFace’ of the Fondation pour la Recherche Médicale to OBB, Project ‘Cardannex’ of Inserm Transfert to OBB. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.