Increased lipolysis and altered lipid homeostasis protect γ-synuclein-null mutant mice from diet-induced obesity.

Autor: Millership S; School of Biosciences, Cardiff University, Cardiff CF10 3AX, United Kingdom., Ninkina N, Guschina IA, Norton J, Brambilla R, Oort PJ, Adams SH, Dennis RJ, Voshol PJ, Rochford JJ, Buchman VL
Jazyk: angličtina
Zdroj: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2012 Dec 18; Vol. 109 (51), pp. 20943-8. Date of Electronic Publication: 2012 Dec 03.
DOI: 10.1073/pnas.1210022110
Abstrakt: Synucleins are a family of homologous proteins principally known for their involvement in neurodegeneration. γ-Synuclein is highly expressed in human white adipose tissue and increased in obesity. Here we show that γ-synuclein is nutritionally regulated in white adipose tissue whereas its loss partially protects mice from high-fat diet (HFD)-induced obesity and ameliorates some of the associated metabolic complications. Compared with HFD-fed WT mice, HFD-fed γ-synuclein-null mutant mice display increased lipolysis, lipid oxidation, and energy expenditure, and reduced adipocyte hypertrophy. Knockdown of γ-synuclein in adipocytes causes redistribution of the key lipolytic enzyme ATGL to lipid droplets and increases lipolysis. γ-Synuclein-deficient adipocytes also contain fewer SNARE complexes of a type involved in lipid droplet fusion. We hypothesize that γ-synuclein may deliver SNAP-23 to the SNARE complexes under lipogenic conditions. Via these independent but complementary roles, γ-synuclein may coordinately modulate lipid storage by influencing lipolysis and lipid droplet formation. Our data reveal γ-synuclein as a regulator of lipid handling in adipocytes, the function of which is particularly important in conditions of nutrient excess.
Databáze: MEDLINE