Loureirin B promotes insulin secretion through inhibition of KATP channel and influx of intracellular calcium

The development of new diabetes drugs continues to be explored. Loureirin B, a flavonoid, extracted from Dracaena cochinchinensis, has been confirmed to increase Insulin secretion and decrease blood glucose levels. For searching the promotion of Insulin secretion with the treatment of loureirin B, experiments were employed based on cell experiments and computational methods. First, promotion of Insulin secretion was dependent on extracellular glucose concentration. At the genetic level, loureirin B enhanced the relative mRNA level of Pdx-1 and MafA. Meanwhile the intracellular level of ATP increased due to the continuous absorption of glucose. Further experiments showed that the currents of K_ATP channel on Ins-1 cells were inhibited and the voltage-dependent calcium channels were subsequently activated. The increase of Cx43 protein expression might mediate the Ca²⁺ to the intracellular. Through computational simulation, we hypothesized that loureirin B might interact with K_ATP channels to promote Insulin secretion. In conclusion, it could be concluded that loureirin B promoted Insulin secretion mainly through increasing mRNA level of Pdx-1, MafA, intracellular ATP level, inhibiting the K_ATP current, influx of Ca²⁺ to the intracellular.