Gallocyanine

Gallocyanine (NCI8642) is a DKK/LRP interaction inhibitor and Wnt/β-catenin signaling pathway activator. Gallocyanine binds to the YWTD repeat domains of LRP5/6, competitively blocks the interaction between DKK and LRP5/6, with an IC₅₀ of approximately 3 μM for inhibiting DKK1 binding to LRP5, an IC₅₀ of 6.38 μM for inhibiting DKK1 binding to LRP6, and a K_i of 14 μM for inhibiting the DKK2C/LRP6-E3E4 interaction. Gallocyanine reverses the inhibitory effect of DKK1 on WNT3A signaling, with an EC₅₀ of approximately 5 μM. Gallocyanine can be used in studies related to Alzheimer's disease, bone formation and glucose metabolism^[1]. In Vitro:Gallocyanine (NCI8642) (1-10 μM) potently reverses DKK1-mediated inhibition of WNT3A-stimulated reporter gene activity in NIH 3T3 cells with an EC₅₀ of ~5 μM^[1].
Gallocyanine (0.1-100 μM) inhibits DKK1-AP binding to wild-type LRP5-expressing HEK293 cells with an IC₅₀ of about 3 μM, without affecting binding to Kremen1-expressing cells^[1].
Gallocyanine inhibits the binding of DKK2C to recombinant LRP6-E3E4 with an inhibition constant of 14 μM^[1].
Gallocyanine (100 μM; 2 h) inhibits DKK1 binding to LRP6 in HEK-293LRP6 cells with an IC₅₀ of 6.38 μM, reducing DKK1 binding to 47.8% at 100 μM^[2].
Gallocyanine (10-100 μM; 24 h) is not cytotoxic to SH-SY5Y cells at concentrations up to 100 μM after 24 hours of incubation^[2].
Gallocyanine (10 μM; 1 h) inhibits PGJ₂-induced Tau phosphorylation at serine 396 in mouse primary cortical neurons, reducing phosphorylation levels to 55% at 10 μM^[2].
Gallocyanine (0.1-10 μM; 1 h) dose-dependently inhibits DKK1-induced Tau phosphorylation at serine 396 in SH-SY5Y cells^[2].
Gallocyanine (0.1-10 μM; 1 h) dose-dependently activates Wnt/β-catenin signaling in SH-SY5Y cells by increasing pGSK3β and β-catenin levels^[2]. In Vivo:Gallocyanine (administered via local subcutaneous injection over the skull; three times daily for 5 consecutive days) promotes local new bone formation in the skull of 6-week-old CD-1 mice, and its effect in this local bone formation assay is comparable to that of the positive control b-FGF^[1].
Gallocyanine (IIIC3; 3.5 or 7.0 mg/kg/day; intraperitoneal injection) exerts no obvious overall effect on whole-body bone mineral density (BMD) in mice, but the BMD of the 3.5 mg/kg/day group increases by approximately 3% at the end of the experiment^[1].
Gallocyanine (IIIC3; i.p.) reduces blood glucose levels during routine toxicity monitoring in mice^[1].