摘要
Urea transporters(UT)play a vital role in the mechanism of urine concentration and are recognized as novel targets for the development of salt-sparing diuretics.Thus,UT inhibitors are promising for development as novel diuretics.In the present study,a novel UT inhibitor with a diarylamide scaffold was discovered by high-throughput screening.Optimization of the inhibitor led to the identifi-cation of a promising preclinical candidate,N-[4-(acetylamino)phenyl]-5-nitrofuran-2-carboxamide(1 H),with excellent in vitro UT inhibitory activity at the submicromolar level.The half maximal inhibitory concentrations of 1 H against UT-B in mouse,rat,and human erythrocyte were 1.60,0.64,and0.13 mmol/L,respectively.Further investigation suggested that 8 mmol/L 1 H more powerfully inhibited UT-A1 at a rate of 86.8%than UT-B at a rate of 73.9%in MDCK cell models.Most interestingly,we found for the first time that oral administration of 1 H at a dose of 100 mg/kg showed superior diuretic effect in vivo without causing electrolyte imbalance in rats.Additionally,1 H did not exhibit apparent toxicity in vivo and in vitro,and possessed favorable pharmacokinetic characteristics.1 H shows promise as a novel diuretic to treat hyponatremia accompanied with volume expansion and may cause few side effects.
基金
supported by National Natural Science Foundation of China(Grant Nos.81620108029,81974083,and 81330074)
Beijing Natural Science Foundation grant 7172113(China)
