(rel)-Asperparaline A

(rel)-Asperparaline A ((rel)-Aspergillimide), an anthelmintic metabolite, is isolated from okara that has been fermented with Aspergillus japonicas JV-23. (rel)-Asperparaline A is also a potent and selective antagonist of nAChR. (rel)-Asperparaline A exhibits paralytic activity in silk worms^[1][2]. In Vitro: Asperparaline A (1 μM; 1 min) markedly and reversibly blocks the acetylcholine (Ach; 10 μM)-induced current in the silkworm larval neurons^[2].
Asperparaline A (1-1000 nM; 1 min) differentially blocks the peak and slowly desensitizing currents, with IC₅₀s of 20.2 and?39.6 nM, respectively^[2].
Asperparaline A (10 μM; 1 min) reduces the peak current amplitude of the ACh (100 μM)-induced response of α3β4 nAChR by 33.4%, while barely influencing the amplitudes of the responses to ACh of the α4β2 and α7 nAChRs in X. laevis oocytes^[2]. In Vivo: Asperparaline A (10 μg/g; p.o.) exhibits paralysis against silk worms within 1 h and lasts for 7 to 10 h^[1].
Asperparaline A (3 μg/g; injection with a micro-syringe) exhibits paralysis activity against silk worms within 20 min and lasts for 4 to 5 h^[1].