1-Azakenpaullone

1-Azakenpaullone inhibits the CDK1/cyclin B, CDK5/p25, and GSK-3β effectively, with IC50 of 0.018 μM, 4.2 μM, and 2.0 μM, respectively. ^[1] In human islets, 1-Azakenpaullone (5 mM) in combination with glucose (8 mM) stimulates the β-cell proliferation. ^[2] 1-Azakenpaullone effectively stimulates INS-1E cells replication and protects INS-1E cells against glucolipotoxicity-induced cell death. ^[3][4]

Pretreatment with 1-Azakenpaullone (10 or 100 pmol, i.c.v.) attenuates the induced locomotor hyperactivity, disruption of PPI and cognitive deficits, and improves the induced motor incoordination in rotarod test. ^[5]

• Kinase preparations and assays

  GSK-3β is assayed, following a 1/100 dilution in 1 mg BSA per mL 10 mM dithiothreitol, with 5 μL 40 μM GS-1 peptide as a substrate, in buffer A, in the presence of 15 μM [γ-³²P]ATP (3000 Ci·mmol^-1; 1 mCi·mL^-1 ) in a final volume of 30 μL. After 30 min incubation at 30℃, 25 μL aliquots of supernatant are spotted onto 2.5×3 cm pieces of Whatman P81 phosphocellulose paper, and 20 s later, the filters are washed five times in a solution of 10 mL phosphoric acid per L of water. The wet filters are counted in the presence of 1 mL ACS scintillation fluid. The kinase activity of CDK1/cyclin B is assayed in buffer C, with 1 mg/mL histone H1, in the presence of 15 μM [γ-32P]ATP (3000 Ci·mmol^-1; 1 mCi·mL^-1 ) in a final volume of 30 μL. After 10 min incubation at 30℃, 25 μL aliquots of supernatant are spotted onto P81 phosphocellulose papers and treated as described above. The activity of CDK5/p25 is assayed in buffer C as described for CDK1/cyclin B. (Buffer A: 10 mM MgCl2 , 1 mM EGTA, 1 mM dithiothreitol, 25 mM Tris/HCl pH 7.5. Buffer C: homogenization buffer but 5 mM EGTA, no NaF and no protease inhibitors.)

• Cell lines

  INS-1E β cell

• Concentrations

  20 μM

• Incubation Time

  4 days

• Method

  Cell replication is determined by BrdUrd incorporation after treatment with 1-Azakenpaullone for 24 h. The relative cell number is determined after treatment with 1-Azakenpaullone for 4 days using the CyQuant cell proliferation assay. Results are presented as fold change relative to control.

• Animal Models

  Male NMRI mice

• Dosages

  ~500 pmol

• Administration

  i.c.v.