Work

Mitochondrial respiration and hydrogen peroxide production rate in right atrial tissues from obese diabetic patients

Year: 2026

Type: article

Abstract: Type 2 diabetes (T2D) is a global epidemic, with heart failure being the leading cause of premature death. Mitochondrial dysfunction, characterized by impaired energy metabolism, weakened energy transport system and increased oxidative stress, has been proposed as a key contributor to the impairment of contractile function in T2D hearts. However, direct evidence from human T2D hearts remains limited. We assessed the mitochondrial function of right atrial tissues obtained from consenting patients undergoing coronary bypass surgery, comparing T2D and non‐diabetic groups. We used high‐resolution respirometry and fluorometry techniques to assess mitochondrial O 2 flux and H 2 O 2 production in permeabilized cardiac fibres in simulated physiological conditions supported by ATP substrate. Our findings showed that O 2 flux during oxidative phosphorylation and ATP‐stimulated respiration states was similar between groups. T2D fibres exhibited a lower H 2 O 2 production rate during the leak state, both per tissue mass and per O 2 consumed, but no group difference was observed in the oxidative phosphorylation respiratory state. These findings suggest that T2D, in the context of other comorbidities, such as coronary artery disease and obesity, might not contribute significantly to mitochondrial dysfunction in the human heart.

Source: Experimental Physiology

DOI: 10.1113/ep093121

Authors: Toan Pham, Sarbjot Kaur, Anthony Hickey, Marie‐Louise Ward, Kenneth Tran

Institution: University of Auckland

Language: English

Topic: Mitochondrial Function and Pathology

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,940