Anti-allergic effect of a combination of Citrus unshiu unripe fruits extract and prednisolone on picryl chloride-induced contact dermatitis in mice

Abstract

Effect of 50% ethanolic extract of unripe fruits of Citrus unshiu (CU-ext) on type IV allergic reaction was examined by inhibitory activity of ear swelling of picryl chloride-induced contact dermatitis (PC-CD) in mice. Oral administration of CU-ext and subcutaneous administration of prednisolone showed inhibition of ear swelling during both induction and effector phases of PC-CD. The inhibitory activities of combinations of CU-ext (p.o.) and prednisolone (s.c.) during induction phase of PC-CD were more potent than those of CU-ext alone and prednisolone alone. Successive oral administration of hesperidin, a major flavanone glycoside of CU-ext, inhibited ear swelling during induction phase of PC-CD. The inhibitory activities of combinations of hesperidin (p.o.) and prednisolone (s.c.) were more potent than those of hesperidin alone and prednisolone alone. These results indicated that the combinations of prednisolone and CU-ext or hesperidin exerted a synergistic effect.

Antiallergic activity of unripe Citrus hassaku fruits extract and its flavanone glycosides on chemical substance-induced dermatitis in mice

“…The combination of CH-ext and prednisolone as well as the combination of various kinds of flavanone glycoside alone and prednisolone exerted synergistic effect without enhancement of adverse reaction of steroidal agents as in the case of the combination of CU-ext and prednisolone as well as the combination of hesperidin and prednisolone [5]. The synergistic effect of combinations of Citrus fruit extract and its flavanone glycosides in combination with prednisolone on ear swelling in PC-CD in mice is a tractable phenomenon.…”

“…Prednisolone, a reference drug, was subcutaneously administered as in the experiments with combinations of CU-ext and prednisolone [5]. Activity of test samples was evaluated by the increase of ear thickness during induction phase of PC-CD in mice.…”

“…Furthermore, we reported that the efficacy of prednisolone was enhanced by administration of a combination of prednisolone [subcutaneous administration (s.c.)] and CU-ext [oral administration (p.o.)] without enhancing the adverse effects that accompany steroidal agents [5].…”

“…As type IV allergic reaction model, we used picryl chloride-induced contact dermatitis (PC-CD) in mice [8], as applied by others [9]. Moreover, we examined whether a combination of CH-ext and prednisolone exerts a synergistic effect on PC-CD in mice, as in the case for CU-ext [5]. In addition, anti-type IV allergic effects of other combinations of prednisolone and major flavanone glycoside components of C. hassaku were studied in the PC-CD model.…”

Extract from peel of Citrus natsudaidai alleviates experimental chronic allergic dermatitis in mice

“…It was reported that extract of unripe Citrus unshiu inhibits ear swelling during both the effector and induction phases in picryl chloride-induced dermatitis model mice. [12] It was also demonstrated that extract of unripe Citrus hassaku and its flavanone glycosides, naringin, and neohesperidin showed antiallergic properties in type I and type IV allergy models in mice. [13] These results suggest that citrus plant extract is beneficial for treatment of allergic dermatitis, but little is known about antiallergic activities of natsumikan.…”