High fat diet exacerbates murine psoriatic dermatitis by increasing the number of IL-17-producing γδ T cells.

Abstract

Psoriasis is a common, chronic inflammatory skin disease characterized by epidermal hyperplasia via the IL-23/IL-17 axis. Various studies have indicated the association between obesity and psoriasis, however, the underlying mechanisms remains unclarified. To this end, we focused on high-fat diet (HFD) in this study, because HFD is suggested as a contributor to obesity, and HFD-fed mice exhibit exacerbated psoriatic dermatitis. Using murine imiquimod (IMQ)-induced psoriasis and HFD-induced obesity models, we have revealed a novel mechanism of HFD-induced exacerbation of psoriatic dermatitis. HFD-fed mice exhibited aggravated psoriatic dermatitis, which was accompanied with increased accumulation of IL-17A-producing Vγ4+ γδ T cells in the skin. HFD also induced the increase of Vγ4+ γδ T cells in other organs such as skin draining lymph nodes, which preceded the increase of them in the skin. In addition, HFD-fed mice displayed increased expression of several γδ T cell-recruiting chemokines in the skin. On the other hand, ob/ob mice, another model of murine obesity on normal diet, did not exhibit aggravated psoriatic dermatitis nor accumulation of γδ T cells in the dermis. These results indicate that HFD is a key element in exacerbation of IMQ-induced psoriatic dermatitis, and further raise the possibility of HFD as a factor that links obesity and psoriasis.

• Authors: Satoshi Nakamizo, Tetsuya Honda, Akimasa Adachi, Takahiro Nagatake, Jun Kunisawa, Akihiko Kitoh, Atsushi Otsuka, Teruki Dainichi, Takashi Nomura, Florent Ginhoux, Koichi Ikuta, Gyohei Egawa, Kenji Kabashima
• Journal: Scientific reports (Sci Rep) Vol. 7 Issue 1 Pg. 14076 (10 26 2017) ISSN: 2045-2322 [Electronic] England
• PMID: 29074858 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• CCL20 protein, mouse
• Chemokine CCL20
• Il17a protein, mouse
• Interleukin-17
• Imiquimod

Topics

• Animals
• Chemokine CCL20 (metabolism)
• Dermatitis (metabolism, pathology)
• Diet, High-Fat (adverse effects)
• Disease Models, Animal
• Endothelial Cells (metabolism, pathology)
• Imiquimod
• Interleukin-17 (metabolism)
• Keratinocytes (metabolism, pathology)
• Male
• Mice, Inbred C57BL
• Mice, Obese
• Obesity (metabolism, pathology)
• Psoriasis (metabolism, pathology)
• Skin (metabolism, pathology)
• T-Lymphocytes (metabolism, pathology)