Diabetes Mellitus Promotes Atrial Structural Remodeling and PARP-1/Ikka/NF-κB Pathway Activation in Mice

Background: Diabetes mellitus (DM) has been demonstrated to be linked to atrial fibrillation (AF). However, the underlying mechanisms of the DM-associated increase in AF susceptibility and the potential effects of DM on atrial remodeling remain unclear. Methods and Results: Twenty-five C57BL/6 mice were randomly assigned to the normal/ control group (Con, n=10) and model group (n=15). Mice in the model group were administered a high-fat diet combined with multiple injections of low-dose streptozocin (STZ) (35 mg/kg). Eleven mice were ultimately included in DM group. Left atrial tissue structural and inflammatory alterations were assessed. In our study, the atrial weights of DM mice were markedly heavier than those of mice in the Con group. DM mice exhibited significantly increased fasting plasma glucose, fasting insulin, and dyslipidaemia. Furthermore, H&E and Masson's staining revealed broadened interstitial spaces, myocyte disarray and atrial fibrosis in DM mice. The expression levels of the atrial inflammation-associated factor nuclear factor.B (NF-kappa B) and its pathway were significantly altered in the atria of DM mice. Conclusion: DM could induce atrial structural remodeling and inflammation in mice.

Automated summary

The study found that diabetic mice had increased atrial weight, significantly altered expression levels of inflammation factor NF-kappa B, and widespread fibrosis in the atria. This suggests that diabetes may induce atrial structural remodeling and inflammation in mice.