Department of Dermatology, Nippon Medical School, Bunkyo City 113-8602, Tokyo, Japan.
Department of Applied Science, School of Veterinary Nursing and Technology, Nippon Veterinary and Life Science University, Musashino 180-8602, Tokyo, Japan.
Int J Mol Sci. 2023 Sep 17;24(18):14197. doi: 10.3390/ijms241814197.
Psoriasis is a chronic skin disease with interleukin (IL)-17-dominated inflammation and hyperproliferation of epidermis. Dietary fiber is fermented by the gut microbiome into short-chain fatty acids (SCFAs) that manifest anti-inflammatory effects. We examined if feeding with an inulin-enriched high-fiber diet (HFD) might improve topical imiquimod-induced psoriasis-like dermatitis in mice. HFD reduced thickening and total severity scores of imiquimod-induced dermatitis and reduced epidermal thickness, inflammatory infiltrates, including Ly6G+ neutrophils, and epidermal Ki67+ proliferating cells. HFD reduced mRNA levels of IL-17A, IL-17F, IL-22, IL-1β, tumor necrosis factor (TNF)-α, CXCL1, CXCL2, and keratin 16 and increased those of transforming growth factor (TGF)-β1 and cyclin-dependent kinase inhibitor 1A in imiquimod-induced dermatitis. In 16S rRNA sequencing of the gut microbiome, imiquimod increased relative abundance of phylum Firmicutes, while HFD increased that of phylum Bacteroidota and genus . HFD increased serum and fecal concentrations of SCFA propionate. Oral propionate reduced inflammatory infiltrates and epidermal Ki67+ cells and reduced mRNA levels of IL-17A, IL-17F, IL-17C, IL-22, IL-1β, IL-6, TNF-α, CXCL1, CCL20 and increased those of TGF-β1and IL-10 in imiquimod-indued dermatitis. Dietary inulin supplementation improves imiquimod-induced psoriasis-like dermatitis partially via propionate, and may be a promising adjunctive therapy for psoriasis.
银屑病是一种慢性皮肤病，其炎症和表皮过度增生以白细胞介素（IL）-17 为主导。膳食纤维被肠道微生物群发酵成短链脂肪酸（SCFAs），表现出抗炎作用。我们研究了富含菊粉的高纤维饮食（HFD）是否可以改善咪喹莫特诱导的小鼠银屑病样皮炎。HFD 降低了咪喹莫特诱导的皮炎的增厚和总严重程度评分，并降低了表皮厚度、炎症浸润，包括 Ly6G+中性粒细胞和表皮 Ki67+增殖细胞。HFD 降低了咪喹莫特诱导的皮炎中 IL-17A、IL-17F、IL-22、IL-1β、肿瘤坏死因子（TNF）-α、CXCL1、CXCL2 和角蛋白 16 的 mRNA 水平，并增加了转化生长因子（TGF）-β1 和细胞周期蛋白依赖性激酶抑制剂 1A 的水平。在肠道微生物组的 16S rRNA 测序中，咪喹莫特增加了厚壁菌门的相对丰度，而 HFD 增加了拟杆菌门和属的相对丰度。HFD 增加了血清和粪便中丙酸的浓度。口服丙酸减少了炎症浸润和表皮 Ki67+细胞，并降低了咪喹莫特诱导的皮炎中 IL-17A、IL-17F、IL-17C、IL-22、IL-1β、IL-6、TNF-α、CXCL1、CCL20 的 mRNA 水平，增加了 TGF-β1 和 IL-10 的 mRNA 水平。膳食菊粉补充通过丙酸部分改善了咪喹莫特诱导的银屑病样皮炎，可能是银屑病的一种有前途的辅助治疗方法。
