[The intracellular metabolism of neutrophils under different forms of ischemic heart disease]

Area of Science:

• Biochemistry
• Immunology
• Cardiology

Context:

• Investigates intracellular metabolism of neutrophils in patients with ischemic heart disease (IHD).
• Compares metabolic profiles of neutrophils in IHD patients versus controls.
• Examines metabolic changes across different severities of IHD, from unstable angina to myocardial infarction.

Purpose:

• To elucidate the alterations in neutrophil intracellular metabolism during ischemic heart disease.
• To correlate changes in neutrophil function with disease severity and specific biomarkers.
• To understand the role of oxidative stress and immune complexes in IHD-related neutrophil dysfunction.

Summary:

• Patients with IHD exhibit heightened neutrophil production of reactive oxygen species (ROS) alongside reduced intracellular catalase activity and elevated lactate levels in phagocytes.
• Neutrophil metabolic activation, driven by increased circulating immune complexes in severe IHD (myocardial infarction), is not counterbalanced by enhanced antioxidant enzyme activity.
• Maximal activation of neutrophil NAD(F)N-oxidase and a twofold increase in intracellular lactate were observed in Q-wave myocardial infarction patients, suggesting hypoxia-induced intracellular acidosis and phagocyte destruction.

Impact:

• Findings suggest that increased lactate production in neutrophils during myocardial ischemia contributes to intracellular acidosis, oxidative stress, and phagocyte destruction.
• Highlights the imbalance between pro-oxidant activity and antioxidant defense in neutrophils during IHD.
• Provides insights into the cellular mechanisms underlying neutrophil dysfunction in ischemic heart disease, potentially informing therapeutic strategies.