Figure 4.

Pharmacology of AK inhibitors on NRH kinase activity and on NAD⁺ concentration enhancement. HEK293 cells treated with AK inhibitors, a) 5-Itu (26 nM) or b) ABT702 (20 nM), abolished NRH (1 mM) effect in NAD⁺ concentration enhancement, whereas the inhibitors do not affect NR (1 mM) action. Neuro2a cells treated with c) 5-Itu (26 nM) or d) ABT702 (20 nM) lose majority of NRH (1 mM) effect on NAD⁺ concentration enhancement. e) & f) 5-Itu and ABT702 inhibit NRH (1 mM) effect on NAD⁺ concentration increase in HepG2 and C2C12 cells. Data expressed as mean ± SD, n = 4 or 6 biologically independent samples. One-way ANOVA and Tukey’s multiple comparison test were used for statistical analysis, *, p<0.0001 when compared to control or within indicated groups. g) 5-Itu and h) ABT702 inhibit Neuro2a lysate NRH kinase activity as they reduce production of NMNH in a dose-dependent manner. i) AK overexpressed HEK293 cell lysates have NRH kinase activity which is inhibited by 5-Itu or ABT702. Experiments were repeated independently 3 times with similar results.