Figure 1.

Tubeimoside I (TBMS1) inhibits Yoda1-induced Piezo1 activity. (A) Chemical structure of TBMS1. (B) Intracellular Ca²⁺ responses of human umbilical vein endothelial cell (HUVECs) to 5 μM Yoda1 after the cells were pretreated for 30 min with 10 μM TBMS1 or DMSO. Error bars indicate SEM (N = 16 each). (C) Summary of the results presented in (B) expressed as a percentage of the cell response to Yoda1 after cells were pretreated with TBMS1 or DMSO. Error bars indicate SEM (n = 5). (D) Intracellular Ca²⁺ measurements in HUVECs when direct application of 10 μM TBMS1 or DMSO only. Error bars indicate SEM (N = 8 each). (E) Mean data for the results shown in (C) (n = 5). (F) Intracellular Ca²⁺ responses of HUVECs to 5 μM Yoda1 after the cells were pretreated for 30 min with 10 μM TBMS1 or DMSO with original baseline. Error bars indicate SEM (N = 16 each). (G) Mean data for baseline differences of the results shown in (F) (n = 5). (H) Mean data of the results shown in (A) in which cells were pretreated with the indicated concentrations of TBMS1. Fitting the curve to the Hill equation yields an IC₅₀ of 1.11 μM (n=5). *P < 0.05.