This study focused on the effects of
tacalcitol (1,24 (R) (
OH)2D3, TV-02)
ointment (20 micro g/g) on cutaneous
inflammation, epidermal proliferation, and differentiation and compared them with
tacalcitol ointment (2 micro g/g) and other anti-psoriatic
ointments using hairless mice.
Tacalcitol ointment (0, 2 and 20 micro g/g) significantly inhibited 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced cutaneous
inflammation, histopathologically. The effect of
tacalcitol ointment (20 micro g/g) on cutaneous
inflammation was much stronger than that of
tacalcitol ointment (0, 2 micro g/g), and as effective as
calcipotriol ointment (50 micro g/g) or
betamethasone valerate ointment (1.2 mg/g).
Tacalcitol ointment (20 micro g/g) also significantly inhibited TPA-induced
myeloperoxidase (MPO) activity, as effectively as
calcipotriol ointment (50 micro g/g) or
betamethasone valerate ointment (1.2 mg/g). The effect of
tacalcitol ointment on epidermal proliferation [
ornithine decarboxylase (ODC) activity] and differentiation [
transglutaminase (TGase) activity] was dose-dependent from 0 micro g/g to 20 micro g/g. The effect of
tacalcitol ointments on epidermal proliferation was significant at the doses of 2 micro g/g and 20 micro g/g, and that on epidermal differentiation was significant at the doses of 0.2 micro g/g or more. The effect of
tacalcitol ointment (20 micro g/g) on epidermal differentiation was significantly stronger than
tacalcitol ointment (2 micro g/g). In this study,
tacalcitol ointment (20 micro g/g) was found to have a marked effect on cutaneous
inflammation and improved effect on epidermal differentiation, although
tacalcitol ointment (2 micro g/g) also had significant effects on epidermal proliferation and differentiation. These findings support the clinical effectiveness of
tacalcitol ointment (20 micro g/g) against
psoriasis.