Type 2 Diabetes & Heart Failure: New Molecular Insights

A new study sheds light on why people with diabetes are at increased risk of heart failure.

Type 2 Diabetes Causes Molecular Changes in Heart Cells

Researchers at the University of Sydney have uncovered a direct link between type 2 diabetes and specific molecular patterns within the heart, potentially explaining the elevated risk of heart failure in diabetic patients. The study examined heart tissue from both healthy donors and individuals with and without diabetes undergoing heart transplantation.^1–3

The research team found that both type 2 diabetes and ischemic cardiomyopathy – heart disease caused by reduced blood flow – are associated with disruptions in biological processes that lead to remodeling of the heart muscle. This remodeling was characterized by an increase in certain molecules and a decrease in the production of crucial structural proteins responsible for heart muscle contraction and calcium regulation. Understanding these changes is a key step in developing targeted therapies.

Energy Production Compromised in Hearts of People with Diabetes

Further investigation, including RNA sequencing, revealed impaired gene transcription in the hearts of individuals with diabetes, particularly within metabolic pathways related to energy production and tissue structure. This suggests a fundamental disruption in how the heart utilizes energy.

A central finding was that the hearts of people with diabetes struggle to access sufficient fuel for energy production. While healthy hearts can efficiently use ketone bodies, fats, and glucose, individuals with diabetes often exhibit increased glucose uptake.⁴ However, this adaptation is impaired in diabetes due to reduced insulin sensitivity in glucose transporters within heart muscle cells. This fuel shortage stresses the mitochondria – the heart muscle cells’ powerhouses – and exacerbates the molecular hallmarks of advanced heart failure, researchers explain.

Key Takeaways

According to the study, type 2 diabetes leads to mitochondrial dysfunction and structural changes in the heart muscle, ultimately impacting its ability to contract effectively.

“To our knowledge, this is the most comprehensive multi-omics investigation to date of the molecular impact of type 2 diabetes on terminal ischemic and non-ischemic cardiomyopathy in humans,” the study authors concluded.³ “Our results suggest that cardiometabolic dysfunction is further complicated and exacerbated by diabetes in the context of heart failure.”