Inhibitory Mechanisms of Glycoprotein Fraction Derived from Miscanthus sinensis for the Immediate Phase Response of an IgE-Mediated Cutaneous Reaction.

Abstract

We investigated the inhibitory effect of the glycoprotein fraction (fraction 2) extracted from Miscanthus sinensi ANDERSSON (M. sinensis) on biphasic cutaneous reactions in mice passively sensitized with IgE. Biphasic skin reactions with peak responses at 1 (IPR, immediate phase reaction) and 24 h (LPR, late phase reaction) were caused by passive sensitization with an anti-dinitrophenol IgE monoclonal antibody (anti-DNP IgE mAb) followed by an epicutaneous challenge of 0.1% dinitrofluorobenzene (DNFB) in 100% ethanol. Intraperitoneal injection of fraction 2 before the DNFB challenge significantly inhibited the biphasic ear swelling response in passively sensitized mice in a dose-dependent manner (1-30 mg/kg). We also found that fraction 2 was effective at inhibiting the vascular permeability in mouse ear induced by an injection of compound 48/80, histamine or serotonin. In addition, fraction 2 inhibited scratching behavior as well as ear edema observed within 2 h after DNFB challenge. Marked inhibition was observed in both passively sensitized and non-sensitized mice. The locomotor activity of mice was also reduced by the administration of fraction 2 as well as by diphenhydramine. These results suggest that the inhibitory effect of glycoprotein fraction 2 of M. sinensis on an IgE-mediated allergic inflammatory reaction is due to the protection of mediator-induced vascular permeability and that in addition to the inhibition of an inflammatory reaction, a sedative action is responsible for the inhibition of allergy-induced scratching responses.

Effect of Picrorrhiza Rhizoma on Dinitrofluorobenzene-induced Contact Dermatitis (Type I allergy)

“…Therefore DNFB-induced contact dermatitis model has been used for evaluation of a potential treatment candidate for type I allergic dermatitis (Matsuda et al, 2002). DNFB to mice sensitized by DNP-OVA caused edemas similar to an occurrence of allergic dermatitis is IgE antibody dependent appearing 1 h after application of DNFB (Watanabe et al, 1999). In the present study, marked edematous changes, increment of thickness and weights were detected on DNFB challenged ear and paw with pruritis.…”

“…After one week, the mice were challenged by painting 10ìl of 0.1% DNFB solution in ethanol on the inside and outside of the right and left ears as previously (Watanabe et al, 1999). About half animals showing an increment of percent change (over 15%) of ear swelling were chosen Sensitization: Next day of animal selection, the mice were again sensitized by the mixture of DNP-OVA (10 mg) and aluminum hydroxide gel (1 mg) in saline (0.2 ml).…”

“…This irritation will lessen as the allergic dermatitis improves related to anti-inflammation activity (Skinner, 2004;Rossetti et al, 2005). In the present study, the effects of PR aqueous extracts on the DNFB-induced contact dermatitis were monitored by comparing with dexamethasone, 15mg/kg, intraperitoneal treatment, according to previous methods (Watanabe et al, 1999;Matsuda et al, 2002).…”

Effects of Magnetic Infrared Laser on Dinitrofluorobenzene-induced Contact Dermatitis in Mice

“…DNFB, 2,4-dinitrofluorobenzene; MIL, magnetic infrared laser; CA, ear cartilages; Arrow in figure shows the anterior skin thicknesses measured in this study; All H&E stain; Scale bars = 160 μm. allergic dermatitis; they are IgE antibody dependent and appear 1 hr after application of DNFB 24) . In the present study, marked edematous changes, and increment of thickness and weights were detected in DNFB challenged ears and paws with pruritis.…”

“…Mice were sensitized by an intraperitoneal injection of a mixture of DNP-OVA (10 μg) and aluminum hydroxide gel (1 mg) in saline (0.2 ml). After one week, the mice were challenged by painting 10 μl of 0.1% DNFB solution in ethanol on the inside and outside of the right and left ears as previously described 24) . The animals showing an increment of percent change over 15% of ear swelling were chosen.…”