J Invest Dermatol. 2021 Apr 1;S0022-202X(21)01129-5. doi: 10.1016/j.jid.2021.03.015.Online ahead of print.

Mechanisms of broad-band ultraviolet B irradiation-induced itch in mice

Liang Cao ¹, Xueping Yue ¹, Yonghui Zhao ¹, Lixia Du ¹, Zili Xie ¹, Yi Yuan ¹, Sha Zhang ², Feng Li ², Jing Feng ³, Hongzhen Hu ¹

• PMID: 33812858
• DOI: 10.1016/j.jid.2021.03.015

Abstract

Although sunburn can produce severe uncontrollable itching, the underlying mechanisms of ultraviolet (UV) irradiation-induced itch are poorly understood because of a lack of experimental animal models of sunburn itch. Here we established a sunburn-related mouse model and found that Broad-band UVB (BB-UVB) irradiation elicited scratching but not wiping behavior in mice. By using a combination of live-cell Ca²⁺ imaging and quantitative RT-PCR on dorsal root ganglion (DRG) neurons, hematoxylin and eosin staining, immunofluorescence staining of skin preparations, behavioral testing, in combination with genetic and pharmacological approaches, we showed that TRPV1-positive DRG neurons but not mast cells are involved in BB-UVB irradiation-induced itch. Moreover, both genetic and pharmacological inhibition of TRPV1 function significantly alleviated BB-UVB irradiation-induced itch response. Collectively, our results suggest that BB-UVB irradiation evokes itch sensation in mice through promoting TRPV1 channel function in DRG neurons and provide potential therapeutic targets for sunburn-related itch.

Keywords: BB-UVB; Itch model; Sunburn-related itch; TRPV1.