title: Brown but not white adipose cells synthesize omega-3 docosahexaenoic acid in culture.
abstract: Adipose tissue is a complex endocrine organ which coordinates several crucial biological functions including fatty acid metabolism, glucose metabolism, energy homeostasis, and immune function. Brown adipose tissue (BAT) is most abundant in young infants during the brain growth spurt when demands for omega-3 docosahexaenoic acid (DHA, 22:6n-3) is greatest for brain structure. Our aim was to characterize relative biosynthesis of omega-3 long chain polyunsaturated fatty acids (LCPUFA) from precursors in cultured white (WAT) and brown (BAT) cells and study relevant gene expression. Mouse WAT and BAT cells were grown in regular DMEM media to confluence, and differentiation was induced. At days 0 and 8 cells were treated with albumin bound d5-18:3n-3 (d5-ALA) and analyzed 24h later. d5-ALA increased cellular eicosapentaenoic acid (EPA, 20:5n-3) and docosapentaenoic acid (DPA, 22:5n-3) in undifferentiated BAT cells, whereas differentiated BAT cells accumulated 20:4n-3, EPA and DPA. DHA as a fraction of total omega-3 LCPUFA was greatest in differentiated BAT cells compared to undifferentiated cells. Undifferentiated WAT cells accumulated EPA, whereas differentiated cells accumulated DPA. WAT accumulated trace newly synthesized DHA. Zic1 a classical brown marker and Prdm16 a key driver of brown fat cell fate are expressed only in BAT cells. Ppargc1a is 15 fold higher in differentiated BAT cells. We conclude that in differentiated adipose cells accumulating fat, BAT cells but not WAT cells synthesize DHA, supporting the hypothesis that BAT is a net producer of DHA.
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA; College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Qin
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Hui Gyu
authors.initials: HG
authors.lastname: Park
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Ji Yao
authors.initials: JY
authors.lastname: Zhang
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Lawrence
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA; College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China.
authors.forename: Guowen
authors.initials: G
authors.lastname: Liu
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Nivetha
authors.initials: N
authors.lastname: Subramanian
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Kumar S D
authors.initials: KS
authors.lastname: Kothapalli
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Brenna
mesh_terms: D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D002001:Adipose Tissue, Brown / Q000166:cytology / Q000378:metabolism*; D052436:Adipose Tissue, White / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D004281:Docosahexaenoic Acids / Q000378:metabolism; D015118:Eicosapentaenoic Acid / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D051379:Mice
chemical_list: D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid; C026219:docosapentaenoic acid
keywords: Brown adipose tissue; Differentiated; Omega-3 long chain polyunsaturated fatty acids; Undifferentiated; White adipose tissue