Premium
Adipochemokines induced by ultraviolet irradiation contribute to impaired fat metabolism in subcutaneous fat cells
Author(s) -
Kim E.J.,
Kim Y.K.,
Kim S.,
Kim J.E.,
Tian Y.D.,
Doh E.J.,
Lee D.H.,
Chung J.H.
Publication year - 2018
Publication title -
british journal of dermatology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.304
H-Index - 179
eISSN - 1365-2133
pISSN - 0007-0963
DOI - 10.1111/bjd.15907
Subject(s) - subcutaneous fat , ultraviolet irradiation , irradiation , metabolism , medicine , chemistry , endocrinology , adipose tissue , physics , nuclear physics
Summary Background Adipose tissue is now appreciated as the pivotal regulator of metabolic and endocrine functions. Subcutaneous ( SC ) fat, in contrast to visceral fat, may protect against metabolic syndrome and systemic inflammation. We demonstrated that chronic as well as acute ultraviolet ( UV ) irradiation to the skin induces loss of underlying SC fat. UV ‐irradiated SC fat may produce chemokines or cytokines that modulate lipid homeostasis and secretion of adipokines. Objectives To elucidate UV ‐induced specific adipochemokines implicated in UV ‐induced modulation of SC fat. Methods Primary cultured adipocytes were treated with conditioned medium from UV ‐ or sham‐irradiated skin cells. Young and older healthy participants provided SC fat from sun‐exposed and sun‐protected skin. Sun‐protected skin from other participants was irradiated with UV . Differentially expressed adipochemokines were screened by cytokine array, and confirmed in vitro and in vivo . The functions of select adipochemokines involved in lipid metabolism were examined via short interfering RNA ‐mediated knockdown of cognate receptors. Results Specific adipochemokines, including C‐X‐C motif chemokine ( CXCL ) family members such as CXCL 5/ ENA ‐78, and C‐C motif chemokine ( CCL ) family members such as CCL 20/ MIP ‐3α and CCL 5/ RANTES , were greatly induced in SC fat by UV exposure. They could impair triglyceride synthesis via downregulation of lipogenic enzymes and sterol regulatory element‐binding protein‐1 through their respective cognate receptors, CXC chemokine receptor type ( CXC ‐R)2, C‐C chemokine receptor type ( CCR )‐6, and CCR ‐5. In addition, UV irradiation induced infiltration of adipose tissue macrophages responsible for the secretion of several chemokines into SC fat. Conclusions These UV ‐induced adipochemokines may be implicated in the reduction of lipogenesis in SC fat, leading to impairment of fat homeostasis and associated comorbidities such as obesity.