Metabolic Syndrome-Driven Changes in Cardiac Lymphatic Endothelium: mRNA Expression and Emerging Questions.

Background/Objectives: Metabolic syndrome (MetS) conditions lead to structural and functional alterations in cardiomyocytes, microvasculature, and extracellular matrix (ECM), leading to myocardial fibrosis and impaired diastolic function. Cardiac lymphatic vessels (LVs) are increasingly recognized as key regulators of myocardial homeostasis, yet their response to MetS remains poorly understood. Therefore, we aimed to investigate transcriptional changes in cardiac lymphatic endothelial cells (LECs) in db/db mice, a well-established model of MetS. Methods: Using flow cytometry-sorted LECs and RT-PCR, we analyzed mRNA expression of genes involved in lymphangiogenesis, metabolism, mechanotransduction, immune cell trafficking, and ECM interactions. Results: Our findings show the transcriptional plasticity of cardiac LECs in response to MetS. Conclusions: Although our study is limited by the lack of protein-level validation and functional assays, our approach provides a broader interpretative framework and identifies potential directions for future research, including functional studies and pathway-specific investigations of the identified genes to assess their impact on lymphatic flow and cardiac function. Understanding LEC responses to metabolic stress may uncover novel therapeutic targets for heart failure associated with MetS.