The effects of a novel phosphodiesterase 7A and -4 dual inhibitor, YM-393059, on T-cell-related cytokine production in vitro and in vivo

YM-393059, (±)-N-(4,6-dimethylpyrimidin-2-yl)-4-[2-(4-methoxy-3-methylphenyl)-5-(4-methylpiperazin-1-yl)-4,5,6,7-tetrahydro-1H-indol-1-yl]benzenesulfonamide difumarate, is a novel phosphodiesterase (PDE) inhibitor that inhibited the PDE7A isoenzyme with a high potency (IC50 = 14 nM) and PDE4 with a moderate potency (IC50 = 630 nM). In a cell-based assay, YM-393059 was found to inhibit anti-CD3 antibody, Staphylococcal enterotoxin B, and phytohaemagglutinin-induced interleukin (IL)-2 production in mouse splenocytes with IC50 values ranging from 0.48 to 1.1 μM. It also inhibited anti-CD3 antibody-induced interferon (IFN)-γ and IL-4 production in splenocytes with IC50 values of 1.8 and 2.8 μM, respectively. YM-393059's inhibition of anti-CD3 antibody-stimulated cytokine (IL-2, IFN-γ, and IL-4) production was 20- to 31-fold weaker than that of YM976, a selective PDE4 inhibitor. However, orally administered YM-393059 and YM976 inhibited anti-CD3 antibody-induced IL-2 production equipotently in mice. In addition, YM-393059 inhibited lipopolysaccharide-induced tumor necrosis factor-α production in vivo more potently than IL-2 (ED50 values of 2.1 mg/kg and 74 mg/kg). In contrast to YM976, YM-393059 did not shorten the duration of α2-adrenoceptor agonist-induced sleep in mice, which is a model for the assessment of the typical side effects caused by PDE4 inhibitors, nausea and emesis. YM-393059 is a novel and attractive compound for the treatment of a wide variety of T-cell-mediated diseases.