Geraniol targets KV1.3 ion channel and exhibits anti-inflammatory activity in vitro and in vivo

Naturally occurring monoterpenes are known for their various pharmacological activities including anti-inflammation. K V 1.3 ion channel is a voltage-gated potassium channel and has been validated as a drug target for autoimmune and chronic inflammatory diseases like psoriasis . Here we experimentally test the direct interaction between monoterpenes and K V 1.3 ion channel. Our electrophysiological analysis determined that monoterpenes (geraniol, nerol , β-citronellol, citral and linalool) have inhibitory effects on K V 1.3 ion channel. Representatively, geraniol reversibly blocked K V 1.3 currents in a voltage-dependent manner with an IC 50 of 490.50 ± 1.04 μM at +40 mV in HEK293T cells. At the effective concentrations, geraniol also inhibited cytokine secretion of activated human T cells, including IL-2, TNF-α and IFN-γ. In an imiquimod-induced psoriasis-like animal model, geraniol administration significantly reduced psoriasis area and severity index scores, ameliorated the deteriorating histopathology and decreased the degree of splenomegaly . Together, our findings not only suggest that monoterpenes may serve as lead molecules for the development of K V 1.3 inhibitors, but also indicate that geraniol could be considered as a promising therapeutic candidate to treat autoimmune diseases.