Relaxing Effect of TSU-68, an Antiangiogenic Agent, on Mouse Airway Smooth Muscle

BACKGROUND/AIMS:

Recently, some small-molecule compounds that were designed for cancer therapy have acquired new roles in the treatment of pulmonary diseases. However, drug screening aimed at abnormal muscle contraction is still limited. TSU-68 is a potent, orally administered, small-molecule agent that can reduce the vascular endothelial growth factor (VEGF)-induced Ca2+ increase in endothelial cells. We questioned whether TSU-68 could also affect calcium influx and relax airway smooth muscle (ASM) cells. The current study aimed to investigate these effects and to explore the underlying mechanisms.

METHODS:

The effects of TSU-68 on ASM cells were studied in mice using a series of biophysiological techniques, including force measurement and patch-clamp experiments.

RESULTS:

TSU-68 inhibited high K+ or acetylcholine chloride (ACh)-induced pre-contracted mouse tracheal rings in a concentration-dependent manner. Further research demonstrated that the TSU-68-induced ASM relaxation was mediated by calcium, which was decreased by blocking voltage-dependent Ca2+ channels (VDCCs) and non-selective cation channels (NSCCs).

CONCLUSION:

Our data indicated that TSU-68 relaxes tense ASM by reducing the intracellular Ca2+ concentration through blocking VDCCs and NSCCs, which suggested that this small molecule might be useful in the treatment of abnormal smooth muscle.

Related Products

Cat.No.	Product Name	Information
S1470	Orantinib (SU6668)	Orantinib (TSU-68, SU6668) has greatest potency against PDGFR autophosphorylation with Ki of 8 nM in a cell-free assay, but also strongly inhibits Flk-1 and FGFR1 trans-phosphorylation, little activity against IGF-1R, Met, Src, Lck, Zap70, Abl and CDK2; does not inhibit EGFR. Phase 3.

Related Targets

PDGFR