BI-D1870

Biological Activity

BI-D1870 is a specific inhibitor of the p90 RSK (ribosomal S6 kinase) isoforms, which inhibits RSK1, RSK2, RSK3 and RSK4 in vitro. BI-D1870 does not significantly inhibit ten other AGC kinase members and over 40 other protein kinases tested at 100-fold higher concentrations. BI-D1870 does not affect the agonist-triggered phosphorylation of substrates for six other AGC kinases. Additionally, BI-D1870 does not suppress the phorbol ester- or EGF-induced phosphorylation of CREB (cAMP-response-element-binding protein).

Customer Product Validations & Biological Datas

	Source	Cell Death Dis (2013). Figure 5. BI-D1870
	Method	FACS analyses
	Cell Lines	HCT116 cells
	Concentrations	10 μM
	Incubation Time	24 h
	Results	BI-D1870 by itself induced massive apoptosis in p21-deficient cells, whereas wild-type and p53-/- cells were killed by this compound to a much lesser extent, suggesting a close functional relationship between RSKs and p21.

Protocol

Cell Experiment
Cell lines	HEK-293 cells
Preparation method	Prior to stimulation, cells were cultured in the absence of serum for 16 h. Inhibitors were dissolved in DMSO at a 1000-fold higher concentration than they were used at. These inhibitors, or the equivalent volume of DMSO as a control, were added to the tissue culture medium 30 min prior to stimulation, unless indi-cated otherwise. The final concentration of DMSO in the culture medium was 0.1% and had no effect on agonist-induced activ-ation or phosphorylation of any of the substrates examined. The cells were stimulated with the indicated agonists and lysed in 1 ml of ice-cold Lysis Buffer, and centrifuged at 16000 g at 4 °C for 5 min. The supernatants were frozen in liquid nitrogen and stored at −80 °C until use. Protein concentrations were determined using the Bradford method with BSA as the standard.
Concentrations	10 μM
Incubation time	4 h

Animal Experiment
Animal models
Formulation
Dosages
Administration

Conversion of different model animals based on BSA (Value based on data from FDA Draft Guidelines)

Species	Mouse	Rat	Rabbit	Guinea pig	Hamster	Dog
Weight (kg)	0.02	0.15	1.8	0.4	0.08	10
Body Surface Area (m2)	0.007	0.025	0.15	0.05	0.02	0.5
Km factor	3	6	12	8	5	20

Animal A (mg/kg) = Animal B (mg/kg) multiplied by	Animal B Km
	Animal A Km

For example, to modify the dose of resveratrol used for a mouse (22.4 mg/kg) to a dose based on the BSA for a rat, multiply 22.4 mg/kg by the K_m factor for a mouse and then divide by the K_m factor for a rat. This calculation results in a rat equivalent dose for resveratrol of 11.2 mg/kg.

Chemical Information

References

BI-D1870 is a specific inhibitor of the p90 RSK (ribosomal S6 kinase) isoforms in vitro and in vivo.
Sapkota GP, et al. Biochem J. 2007 Jan 1;401(1):29-38. PMID: 17040210.