CHIR-99021 HCl (Laduviglusib HCl) is a highly potent and selective inhibitor of GSK-3α/β, with IC50 values of 10 nM and 6.7 nM respectively. It demonstrates remarkable selectivity for GSK-3, with over 500-fold selectivity over CDC2, ERK2, and other protein kinases. Additionally, CHIR-99021 HCl serves as a robust activator of the Wnt/β-catenin signaling pathway. Moreover, it exhibits the ability to enhance self-renewal in both mouse and human embryonic stem cells. Furthermore, CHIR-99021 HCl induces autophagy [1] [2] [3].

Laduviglusib monohydrochloride is a potent inhibitor of human GSK-3β, demonstrating a K_i value of 9.8 nM. As a small organic molecule, it competitively inhibits GSK3α and GSK3β by binding to their ATP-binding sites. Kinase assay results reveal that Laduviglusib monohydrochloride specifically targets GSK3β (IC 50 =~5 nM) and GSK3α (IC 50 =~10 nM) with minimal impact on other kinases. Studies show that at concentrations of 2.5 μM to 10 μM, Laduviglusib monohydrochloride significantly reduces the viability of ES-D3 cells in a dose-dependent manner, with an IC 50 of 4.9 μM, indicating a substantial reduction in cell viability at these concentrations.

In ZDF rats, administering a single oral dose of Laduviglusib monohydrochloride, either 16 mg/kg or 48 mg/kg, swiftly lowers plasma glucose levels, achieving a peak reduction of approximately 150 mg/dl within 3-4 hours post-dose [1]. Additionally, a one-time administration of Laduviglusib (2 mg/kg) monohydrochloride, 4 hours prior to exposure, markedly enhances survival rates following 14.5 Gy abdominal irradiation (ABI). This treatment significantly inhibits crypt cell apoptosis and the buildup of p-H2AX + cells, while fostering crypt regeneration and increasing villus height. Furthermore, Laduviglusib monohydrochloride enhances the survival of Lgr5 + cells by preventing apoptosis and effectively halts the early reduction of Olfm4, Lgr5, and CD44 markers, observable as soon as 4 hours post-treatment [5].