Adipocyte Ceramides Regulate Subcutaneous Adipose Browning, Inflammation, and Metabolism

作者：Chaurasia Bhagirath^*; Kaddai Vincent Andre; Lancaster Graeme Iain; Henstridge Darren C; Sriram Sandhya; Galam Dwight Lark Anolin; Gopalan Venkatesh; Prakash K N Bhanu; Velan S Sendhil; Bulchand Sarada; Tsong Teh Jing; Wang Mei; Siddique Monowarul Mobin; Guan Yuguang; Sigmundsson Kristmundur; Mellet Natalie A; Weir Jacquelyn M; Meikle Peter J; Yassin M Shabeer Bin M; Shabbir Asim; Shayman James A; Hirabayashi Yoshio; Shiow Sue Anne Toh Ee; Sugii Shigeki

来源：Cell Metabolism, 2016, 24(6): 820-834.

DOI：10.1016/j.cmet.2016.10.002

Adipocytes package incoming fatty acids into triglycerides and other glycerolipids, with only a fraction spilling into a parallel biosynthetic pathway that produces sphingolipids. Herein, we demonstrate that subcutaneous adipose tissue of type 2 diabetics contains considerably more sphingolipids than non-diabetic, BMI-matched counterparts. Whole-body and adipose tissue-specific inhibition/deletion of serine palmitoyltransferase (Sptlc), the first enzyme in the sphingolipid biosynthesis cascade, in mice markedly altered adipose morphology and metabolism, particularly in subcutaneous adipose tissue. The reduction in adipose sphingolipids increased brown and beige/brite adipocyte numbers, mitochondrial activity, and insulin sensitivity. The manipulation also increased numbers of anti-inflammatory M2 macrophages in the adipose bed and induced secretion of insulinsensitizing adipokines. By comparison, deletion of serine palmitoyltransferase from macrophages had no discernible effects on metabolic homeostasis or adipose function. These data indicate that newly synthesized adipocyte sphingolipids are nutrient signals that drive changes in the adipose phenotype to influence whole-body energy expenditure and nutrient metabolism.

• 出版日期2016-12-13