This study was conducted to investigate whether and how Jumihaidokuto (JHT), a traditional Chinese medicine, prevents UVB-induced skin damage in male HR-1 hairless mice. JHT has been traditionally prescribed for patients presenting skin disorders with redness and swelling, and, in Japan, it is approved for prescription to patients with acute and/or purulent skin disorders, hives, acute eczema, and athlete’s foot. Considering the traditional use of JHT, we hypothesized that oral administration of JHT might emerge as an effective strategy to prevent UVB-induced skin damage, such as edema and erythema. Here, we pretreated mice with JHT (1000 mg/kg, p.o.) for 3 weeks and then administered a single dose of UVB irradiation (250 mJ/cm²) on the dorsal skin. UVB irradiation increased the erythema index and transepidermal water loss (TEWL) and decreased the skin water content in the epidermis at 72 h post-irradiation. JHT treatment inhibited the increase of TEWL and the loss of water content in the epidermis, but not the elevation of the erythema index. Moreover, administration of JHT suppressed UVB-induced epidermal hyperplasia by blocking the proliferation of keratinocytes and also inhibited irradiation-triggered reduction of collagen fibers and infiltration of immune cells into the dermis. Lastly, administration of JHT suppressed UVB-induced production of proinflammatory mediators, such as prostaglandin E2 and interleukin-1β. These results suggest that JHT prevents UVB-induced skin damage and that the underlying mechanism involves the inhibition of proinflammatory mediators.

这项研究旨在调查传统中药Jumihaidokuto (JHT) 是否以及如何预防雄性 HR-1 无毛小鼠的 UVB 引起的皮肤损伤。JHT 传统上是为出现红肿皮肤病的患者开处方的，在日本，它被批准为患有急性和/或化脓性皮肤病、荨麻疹、急性湿疹和脚癣的患者开处方。考虑到 JHT 的传统用途，我们假设口服 JHT 可能成为预防 UVB 引起的皮肤损伤（如水肿和红斑）的有效策略。在这里，我们用 JHT (1000 mg/kg, po) 预处理小鼠 3 周，然后给予单剂量的 UVB 照射 (250 mJ/cm ²) 在背部皮肤上。UVB 照射增加了红斑指数和经表皮水分流失 (TEWL)，并降低了照射后 72 小时表皮中的皮肤水分含量。JHT处理抑制表皮TEWL的增加和含水量的损失，但不抑制红斑指数的升高。此外，JHT 的施用通过阻断角质形成细胞的增殖来抑制 UVB 诱导的表皮增生，并且还抑制辐射引发的胶原纤维减少和免疫细胞浸润到真皮中。最后，JHT 的施用抑制了 UVB 诱导的促炎介质的产生，例如前列腺素 E2 和白细胞介素 1β。这些结果表明，JHT 可防止 UVB 诱导的皮肤损伤，其潜在机制涉及抑制促炎介质。