Markers of halogenating stress and netosis in patients with type 2 diabetes mellitus

BACKGROUND: Leukocyte myeloperoxidase catalyzes the formation of reactive halogen species, which oxidize and chlorinate biomolecules, thereby contributing to the development of halogenating stress. Myeloperoxidase is a key enzyme in neutrophil extracellular traps (NETs) during NETosis. There is reason to believe that under hyperglycemic conditions in patients with type 2 diabetes mellitus, halogenating stress and NETosis develop, which contribute to disease progression and complications. AIM: The work aimed to assess the levels of blood markers of halogenating stress (myeloperoxidase, chlorinated albumin) and NETosis (neutrophil extracellular traps) in patients with type 2 diabetes mellitus. METHODS: The study included patients with a previously established diagnosis of type 2 diabetes mellitus. Myeloperoxidase and chlorinated albumin in plasma were measured by enzyme-linked immunosorbent assay. The number of neutrophil extracellular traps was determined using light microscopy on standardized whole-blood smears stained according to Romanowsky. RESULTS: In patients with type 2 diabetes mellitus, blood levels of myeloperoxidase and chlorinated albumin were significantly higher than in the group of healthy volunteers, indicating the development of halogenating stress. At the same time, in the blood of patients with type 2 diabetes mellitus, a significant increase in the concentration of neutrophil extracellular traps was recorded compared to the control group of healthy volunteers, both in the absence of the activator—phorbol 12-myristate 13-acetate—and after its addition to the blood, indicating activation of NETosis in type 2 diabetes mellitus. CONCLUSION: The findings support the hypothesis that halogenating stress, caused by an excessive increase in blood myeloperoxidase concentration/activity, accompanies the development of type 2 diabetes mellitus and contributes to its progression and complications.