Discovery of zolinium TSG1180 as a novel agonist of transgelin-2 for treating asthma

Asthma is a complex and heterogeneous respiratory disease that causes serious social and economic burdens. Current drugs such as β2-agonists cannot fully control asthma. Our previous study found that Transgelin-2 is a potential target for treating asthmatic pulmonary resistance. Herein, we discovered a zolinium compound, TSG1180, that showed a strong interaction with Transgelin-2. The equilibrium dissociation constants (KD) of TSG1180 to Transgelin-2 were determined to be 5.363 × 10−6 and 9.81 × 10−6 M by surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC). Cellular thermal shift assay (CETSA) results showed that the thermal stability of Transgelin-2 increased after coincubation of TSG1180 with lysates of airway smooth muscle cells (ASMCs). Molecular docking showed that Arg39 may be the key residue for the binding. Then, the SPR result showed that the binding affinity of TSG1180 to Transgelin-2 mutant (R39E) was decreased by 1.69-fold. Real time cell analysis (RTCA) showed that TSG1180 treatment could relax ASMCs by 19 % (P