Development of heart failure with preserved ejection fraction in type 2 diabetic mice is ameliorated by preserving vascular function.

AIMS

Heart failure with preserved ejection fraction (HFpEF) is associated with endothelial dysfunction and is frequent in people with type 2 diabetes mellitus. In diabetic patients, increased levels of the eicosanoid 12-hydroxyeicosatetraenoic acid (12-HETE) are linked to vascular dysfunction. Here, we aimed to identify the importance of 12-HETE in type 2 diabetic patients exhibiting diastolic dysfunction, and mice exhibiting HFpEF and whether targeting 12-HETE is a means to ameliorate HFpEF progression by improving vascular function in diabetes.

MATERIAL AND METHODS

Subjects with diagnosed type 2 diabetes mellitus and reported diastolic dysfunction or healthy controls were recruited and 12(S)-HETE levels determined by ELISA. 12(S)-HETE levels were determined in type 2 diabetic, leptin receptor deficient mice (LepR) and HFpEF verified by echocardiography. Mitochondrial function, endothelial function and capillary density were assessed using Seahorse technique, pressure myography and immunohistochemistry in LepR or non-diabetic littermate controls. 12/15Lo generation was inhibited using ML351 and 12(S)-HETE action by using the V1-cal peptide.

KEY FINDINGS

Endothelium-dependent vasodilation and mitochondrial functional capacity both improved in response to either application of ML351 or the V1-cal peptide. Correlating to improved vascular function, mice treated with either pharmacological agent exhibited improved diastolic filling and left ventricular relaxation that correlated with increased myocardial capillary density.

SIGNIFICANCE

Our results suggest that 12-HETE may serve as a biomarker indicating endothelial dysfunction and the resulting cardiovascular consequences such as HFpEF in type 2 diabetic patients. Antagonizing 12-HETE is a potent means to causally control HFpEF development and progression in type 2 diabetes by preserving vascular function.