TY-52156

Novel S1P3 receptor antagonist

Binding & Affinity

• TY-52156 is a selective antagonist of the S1P₃ (sphingosine-1-phosphate receptor subtype 3).

• It has a Ki of about 110 nM for S1P₃.

• It inhibits S1P-induced intracellular calcium release in HUVEC (human endothelial) cells.

Effective Doses / Pharmacodynamics in Animals

• Orally, TY-52156 at 10 mg/kg and 30 mg/kg doses suppresses S1P₃-mediated bradycardia induced by FTY-720 in vivo (in animals). 

• In the leukocyte-rolling / endothelial P-selectin mobilization study in mice: TY-52156 was given intraperitoneally (i.p.) at 1.25 mg/kg 30 minutes before the experiment. This dose produced a “dramatic reduction in leukocyte rolling.” ResearchGate

Side Effects or Observed Physiological Effects

• The ability of TY-52156 to suppress FTY-720-induced bradycardia suggests it can mitigate one of the known side-effects of FTY-720 (which activates S1P₃ among others) by blocking S1P₃. ResearchGate+2

• Evidence from vascular studies: TY-52156 blocks S1P-induced decrease in coronary flow (a vasoconstrictive effect) in isolated perfused rat hearts, and blocks Rho activation and calcium signalling in coronary artery smooth muscle cells. In those studies, TY-52156 reduces vasoconstriction mediated by S1P₃. PubMed+1

Limitations / What’s Unknown

• Detailed pharmacokinetic parameters (e.g. plasma half-life, tissue distribution, metabolic rate) are less well documented in the literature.

• Information on chronic dosing side-effects (beyond acute bradycardia or vascular effects) is sparse.

• Data in larger mammals or toxicity studies are not widely published (to my knowledge).

• No human clinical data (safety, tolerability, side effects) is currently available.