IKK 16 (IKK Inhibitor VII) is a selective IκB kinase (IKK) inhibitor for IKK-2, IKK complex and IKK-1 with IC50 of 40 nM, 70 nM and 200 nM, respectively.

IKK2:40 nM, IKK1:200 nM, IKKϵ:70 nM, LRRK2:50 nM

IKK-16 inhibits TNFα-stimulated expression of the adhesion molecules E-selectin, ICAM-1, and VCAM-1 in HUVEC cells. Although IKK-16 shows activity in the IFNγ-induced expression of β2 microglobulin or HLA-DR, its potency in these assays is 4- to 10-fold weaker. [1]

IKK-16 is orally bio-available in rats and mice, and it inhibits LPS-induced TNF-α release in vivo and neutrophil extravasion in thioglycollate-induced peritonitis.[1]

IKK 16 is prepared in DMSO and stored, and then diluted with appropriate medium before use[2]. Human umbilical vein vascular endothelial cells line (HUVECs) are cultured in DMEM supplemented with 10% fetal bovine serum, streptomycin, and penicillin. The cells is grown at 37°C in a humidified 5% CO2 atmosphere. Cells are pretreated with IKK 16 (10 μmol/mL) for 1 hr. The cells are then cultured with TGF-β1 (20 ng/mL) and AT-RvD1 (20 ng/mL). After incubation, the gene expressions of Nrf2 and Smad7 are determined by RT-PCR. The protein expression of Nrf2 and IκBα are determined by Western blot[2].

IKK 16 is prepared in DMSO and diluted with saline or PBS.Rats and MiceIKK 16 is tested in two animal models. First, its efficacy to inhibit TNFα release into plasma upon LPS-challenge in the rat is determined. IKK 16 is dosed sc (30 mg/kg) or orally (30 mg/kg) 1 h prior to the LPS-challenge. Four hours after the challenge, plasma is collected and the systemic TNFα levels are analyzed using a commercially available ELISA kit. Both routes of administration of IKK 16 at the indicated dose results in a significant inhibition of 86% (sc) and 75% (p.o.). In a second experiment, IKK 16 is also active in the thioglycollate-induced peritonitis model in the mouse. The maximal inhibition of neutrophil extravasation in this model is about 50% at a dose of 10 mg/kg sc. MiceTwo-month-old male C57BL/6 mice receive LPS (9 mg/kg body weight) and PepG (3 mg/kg body weight) in 0.9% saline (5 mL/kg body weight) intraperitoneally. Sham mice are not subjected to LPS/PepG, but are otherwise treated the same way. At 1 hour after LPS/PepG co-administration, mice are treated either with IKK 16 (1 mg/kg body weight i.v.) or vehicle (5 mL/kg body weight 10% DMSO i.v.). At 24 hours the experiment is terminated and organ and blood samples are collected for quantification of organ dysfunction and/or injury. Mice are randomly allocated into four different groups: (1) sham+vehicle (n=10); (2) sham+IKK 16 (n=3); (3) LPS/PepG+vehicle (n=9); (4) LPS/PepG+IKK 16 (n=10).They are for reference only.