Antipruritic effect of curcumin on histamine-induced itching in mice

• Published in: The Korean journal of physiology & pharmacology Vol. 22; no. 5; pp. 547 - 554
• Main Authors: Lee, Han Kyu, Park, Seok Bum, Chang, Su-youne, Jung, Sung Jun
• Format: Journal Article
• Language: Korean
• Published: 대한생리학회-대한약리학회 30.09.2018; The Korean Journal of Physiology & Pharmacology Editorial Office
• Subjects: Histamine; Curcumin; TRPV1; Itching
• ISSN: 1226-4512; 2093-3827

Itching is a common clinical symptom of skin disease that significantly affects a patient's quality of life. Transient receptor potential vanilloid 1 (TRPV1) receptors of keratinocytes and peripheral nerve fibers in skin are involved in the regulation of itching as well as pain. In this study, we investigated whether curcumin, which acts on TRPV1 receptors, affects histamine-induced itching in mice, using behavioral tests and electrophysiological approaches. We found that histamine-induced itching was blocked by topical application of curcumin in a concentration-dependent manner. In ex-vivo recordings, histamine-induced discharges of peripheral nerves were reduced by the application of curcumin, indicating that curcumin acts directly on peripheral nerves. Additionally, curcumin blocked the histamine-induced inward current via activation of TRPV1 (curcumin $IC_{50}=523nM$). However, it did not alter chloroquine-induced itching behavior in mice, which is associated with transient receptor potential ankyrin 1 (TRPA1). Taken together, our results suggest that histamine-induced itching can be blocked by topical application of curcumin through the inhibitory action of curcumin on TRPV1 receptors in peripheral nerves.