Fish oil as a potential activator of brown and beige fat thermogenesis

ABSTRACT

Numerous studies have shown that feeding rodents n-3 polyunsaturated fatty acids attenuates adiposity. Moreover, meta-analyses of human dietary intervention studies indicate that fish oil (eicosapentaenoic and docosahexaenoic acid) supplementation might reduce waist circumference. A recent line of research suggests that browning of white adipose depots and activation of uncoupled respiration in brown fat contributes to these effects. This mini-review summarizes the observations in rodents, highlights several mechanisms that might explain these observations and discusses the translational potential. Given the available in vivo evidence and the ability of human adipocytes to aquire a beige phenotype in response to eicosapentaenoic acid incubation, future studies should test the hypothesis that fish oil activates thermogenic brown and beige adipose tissue in humans.

KEYWORDS:

• Fish oil
• eicosapentaenoic acid
• brown adipose tissue
• browning
• beige adipocytes
• UCP1
• non-shivering thermogenesis
• GPR120
• TRPV1
• miR-30b

Abbreviations

AMPK	=	AMP-activated kinase
BAT	=	brown adipose tissue
DHA	=	docosahexaenoic acid
EPA	=	eicosapentaenoic acid
eWAT	=	epididymal white adipose tissue
FFAR4	=	free fatty acid receptor 4
FGF21	=	fibroblast growth factor 21
GPCR	=	G protein-coupled receptor
GPR120	=	G protein-coupled receptor 120
iBAT	=	interscapular brown adipose tissue
IL-4	=	interleukin-4
iWAT	=	inguinal white adipose tissue
n-3 LCPUFAs	=	long-chain n-3 polyunsaturated fatty acids
NE	=	norepinephrine
NST	=	non-shivering thermogenesis
SNS	=	sympathetic nervous system
TRPV1	=	transient receptor potential cation channel subfamily V member 1
UCP1	=	uncoupling protein 1
VEGF-A	=	vascular endothelial growth factor A
WAT	=	white adipose tissue.

Disclosure statements

LHL has received research materials and research funding from Rimfrost A/S and Orkla Care Denmark. JL and LL report no conflict of interest.

Additional information

Funding

This work was supported by the European Union's Seventh Framework Program under the Grant agreement no 613979 (MyNewGut) and by a Novo Scholarship granted to JL.