Introduction

Vascular smooth muscle cell (VSMC) phenotypic modulation (PM) is a central process in vascular remodeling, involving dedifferentiation from a contractile to a synthetic/migratory state. While ion channels have been increasingly recognized as regulators of cell behavior beyond membrane excitability, their role in extracellular matrix (ECM) interactions remains poorly understood. The voltage-gated potassium channel Kv1.3 has been reported to physically and functionally associate with β1 integrins in immune and cancer cells, forming mechanochemical hubs that link ion fluxes to cytoskeletal remodeling, adhesion, and migration^1,2. We hypothesized that Kv1.3–ECM interactions represent a key mechanism driving early VSMC dedifferentiation and that Kv1.3 plays a general role in VSMC PM through its interaction with the ECM.

Material and Methods

The institutional ethics committee approved all animal protocols, which comply with Directive 2010/63/EU. Vascular remodeling was explored in an endoluminal lesion model³of femoral arteries from WT and Kv1.3 knockout (Kv1.3^-/-) mice with immune-histochemical techniques. Kv1.3–ECM interactions were studied in HEK293 cells overexpressing Kv1.3 or Kv1.5 or a poreless Kv1.3, and primary femoral VSMCs from WT and Kv1.3^-/-mice. Adhesion assays were performed on fibronectin (FN)- or poly-L-lysine (PLL)-coated surfaces, and cell motility was evaluated using single-cell tracking assays for up to 48h. Integrin β1 and Kv1.3 channel blockers were used to explore mechanisms, and AAV-Kv1.3 transduction of Kv1.3^-/- VSMC to rescue KO phenotype.

Results

Kv1.3^-/- femoral arteries showed increased wall thickness and reduced cell number at baseline, consistent with a dedifferentiated phenotype, and developed less intimal hyperplasia after injury. At the cellular level, Kv1.3^-/- VSMCs were larger and showed a transcriptional profile consistent with dedifferentiation, with upregulation of OPN and downregulation of CNN1and KCNA5 genes.

Kv1.3 (but not Kv1.5) expression significantly enhanced HEK cell adhesion to FN and increased cell motility independently of ion flux. In native VSMCs, Kv1.3^-/- showed impaired adhesion to FN. Adhesion was dependent on the Kv1.3–integrin β1 interaction and sensitive to channel blockers, indicating a functional role of Kv1.3 channels. Kv1.3^-/- VSMCs exhibited changes in motility that were partially normalized with AAV-mediated Kv1.3 re-expression.

Conclusions

Kv1.3 actively contributes to VSMC adhesion and migration through its interaction with integrin β1. The vascular phenotype of Kv1.3^-/-mice supports the conclusion that Kv1.3–ECM interactions are functionally relevant for vascular remodeling following PM. These findings position Kv1.3 as an early molecular switch in VSMC dedifferentiation, with potential implications for understanding and targeting pathological vascular remodeling.